description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to methods and apparatus for detecting torsional vibration in a bottomhole assembly mounted on the drill string of a rotary drilling system for drilling in an earth formation. As is well known, a rotary drilling system is a system in which the bottomhole assembly, including the drill bit, is mounted on a drill string which extends downhole and is rotated from the surface.
2. Description of Related Art
The invention is particularly, but not exclusively, applicable to bottomhole assemblies including rotary drag-type drill bits of the kind comprising a bit body having a shank for connection to a drill collar on a drill string, a plurality of cutters mounted on the bit body, and means for supplying drilling fluid to the surface of the bit body to cool and clean the cutters and to carry cuttings to the surface. In one common form of bit some or all of the cutters are preform (PDC) cutters each comprising a tablet, usually circular or part-circular, made up of a superhard table of polycrystalline diamond, providing the front cutting face of the element, bonded to a substrate, which is usually of cemented tungsten carbide.
While such PDC bits have been very successful in drilling relatively soft formations, they have been less successful in drilling harder formations or soft formations which include harder occlusions or stringers. Although good rates of penetration are possible in harder formations, the PDC cutters may suffer accelerated wear and bit life can be too short to be commercially acceptable.
Studies have suggested that the rapid wear of PDC bits in harder formations can be due to damage of the cutters as a result of impact loads caused by torsional vibration of the bottomhole assembly.
Torsional vibration can have the effect that cutters on the drill bit may momentarily stop or be rotating backwards, i.e. in the reverse rotational direction to the normal forward direction of rotation of the drill bit during drilling. This is followed by a period of forward rotation of up to twice the RPM mean value. It is believed that it is this behaviour which may be causing excessive damage to the cutters of PDC bits when drilling harder formations where torsional vibration is more likely to occur. The effect of reverse rotation on a PDC cutter may be to impose unusual loads on the cutter which tend to cause spalling or delamination, i.e. separation of part or all of the polycrystalline diamond facing table from the tungsten carbide substrate.
If it is known that torsional vibration is occurring in the bottomhole assembly, it may be possible for the operator of the rotary drilling system, at the surface, to reduce or stop the vibration by modifying the drilling parameters, for example by changing the speed of rotation of the drill string (RPM) and/or the weight-on-bit (WOB). However, it has hitherto been difficult to detect at the surface torsional vibration which is occurring in the bottomhole assembly, since many different frequencies of vibration may be transmitted to the surface and the high frequency vibrations become very attenuated as they pass upwardly along the drill string so that the amplitudes are much reduced at the surface. Accordingly, it has not been reliably possible, hitherto, to detect the onset of torsional vibration of the bottomhole assembly (except very low frequency vibrations which are dependent on depth) by monitoring general torque levels at the surface. It is possible to monitor torsional vibration of the bottomhole assembly by sensors located downhole, in the assembly itself, and transmitting signals from the downhole sensors to the surface. While this may be done in test rigs, it is not generally a practical proposition in commercial drilling.
It would therefore be desirable to be able to monitor torque vibration in the drill string, at the surface, in such a manner that the presence of torsional vibration in the bottomhole assembly can be detected at the surface, and it is this problem which the present invention sets out to solve.
The present invention is based on the realization that the frequencies of torsional vibrations of a bottomhole assembly are associated with the natural resonance frequencies of the drill collars and other components of the bottomhole assembly, and particularly in the modes which involve integer wavelengths, e.g. one or two full wavelengths, of the bottomhole assembly only. The frequencies of these modes can be calculated from the geometry of the bottomhole assembly alone and do not depend on local drilling parameters. The present invention is therefore based on the concept of monitoring at the surface only those frequencies which are in the region of the natural frequencies of the bottomhole assembly.
SUMMARY OF THE INVENTION
According to the invention, therefore, there is provided a method of detecting torsional vibration in a bottomhole assembly mounted on a drill string of a rotary drilling system for drilling in an earth formation, the method including the steps of:
(a) ascertaining natural frequencies of torsional vibration of the bottomhole assembly prior to drilling,
(b) noting at least one reference frequency for an integer wavelength mode of torsional vibration of the bottomhole assembly, and
(c) during subsequent drilling, monitoring the drill string torque at or near the surface for a bandwidth around said reference frequency.
Thus, if the monitoring at the surface detects significant vibration of the drill string at a frequency corresponding to a pre-ascertained natural frequency of the bottomhole assembly, it may be inferred that torsional vibration of the bottomhole assembly is occurring. Alternatively, if the amplitude of the detected torsional vibration is not significant, it may be monitored over time so that any significant increase in the torsional vibration at the reference frequency may be noted. The operator may then take steps to reduce or eliminate the downhole torsional vibration by modifying one or more drilling parameters such as RPM or WOB.
Preferably, the natural frequencies of torsional vibration of the bottomhole assembly are ascertained by use of a computer program which determines the natural frequencies of an assembly from input of parameters of the assembly, such as dimensions, mass, rotary inertia and flexibility of the assembly or components thereof. However, it will be appreciated that the natural frequencies might also be ascertained by other means, for example by physical testing of the actual bottomhole assembly itself.
The monitoring of the surface torque of the drill string may be effected by coupling a surface torque sensor to the drill string and transmitting the output signal from the torque sensor to a computer which has been programmed to analyze the signal and produce an output indicating variation of the torque for a bandwidth around the aforesaid pre-ascertained reference frequency of the bottomhole assembly, said reference frequency having previously been input as a parameter into the signal analyzing program of the computer.
The output signal from the surface torque sensor may be digitally sampled by the computer program for a succession of short periods. The signal is preferably sampled at a rate of at least 300 Hz. The output signal may be an analogue signal which is digitized before being transmitted to the computer.
The method may include the further step of producing a spectral density function from each sampled signal, identifying that part of the function lying within a selected narrow bandwidth around said reference frequency of the bottomhole assembly, and monitoring that part of the function over time. For example, the area under the function lying within said selected narrow bandwidth may be calculated and the value of that area monitored over time.
Thus, the area of the spectral density function within the selected bandwidth may be plotted against time on a visual output from the computer, e.g. on a visual display or print-out. Changes in the value over time may then give warning of the onset of torsional vibration in the bottomhole assembly, or indicate its successful elimination.
The invention also provides means for carrying out the above methods, comprising a surface torque sensor for coupling to the drill string at or near the surface, and means for transmitting an output signal from the torque sensor to a computer, the computer being programmed to analyze the signal and produce an output indicating variation of the mean square torque for a bandwidth around a reference frequency previously input as a parameter into the signal analyzing program of the computer.
The output from the surface torque sensor may be an analogue torque signal, an analogue-digital converter being provided to digitize said output signal and transmit a corresponding digital signal to the computer.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows diagrammatically a system for monitoring, at the surface, torsional vibrations transmitted to the surface from the bottomhole assembly of a rotary drilling system.
FIG. 2 shows the mean square surface torque vibration levels in a particular rotary drilling system, for a broad frequency range.
FIG. 3 shows the same vibration levels reduced to those frequencies close to the resonant frequency of the bottomhole assembly.
FIG. 4 is a plot of torque spectral density of surface torque measurements.
FIG. 5 is a plot of torque against RPM for a rotary drilling assembly.
FIG. 6 is a similar plot to FIG. 5 under different drilling conditions.
FIG. 7 shows the relationship between torque and RPM in a series of test drilling, with the same bit, through different types of formation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows diagrammatically a system for monitoring torsional vibrations transmitted to the surface from the bottomhole assembly of a rotary drilling system. The bottomhole assembly 10 of the drilling system includes a drill bit 11 and is connected to the lower end of a drill string 12 which extends to the surface and is rotatably driven from the surface by a rotary table 13 on a drilling rig 14 . The rotary table 13 is driven by a drive motor (not shown) and raising and lowering of the drill string, and application of weight-on-bit (WOB), is under the control of draw works indicated diagrammatically at 15 .
As is well known, the bottomhole assembly will include, in addition to the drill bit, a variety of other possible components such as drill collars, stabilizers, steering equipment, MWD (measurement-while-drilling) equipment, etc. The particular nature of such components does not form part of the present invention and the various types of component will not therefore be described in detail, being well known to those skilled in this art.
As previously explained, during drilling the drill string and bottomhole assembly may be subject to torsional vibration, and FIG. 1 also shows apparatus for monitoring the vibrations which are transmitted to the surface along the drill string.
The apparatus comprises a torque sensor 16 which is coupled to the upper end of the drill string 12 and transmits an analogue signal 17 , representative of drill string torque, to an analogue-digital converter 18 . The digitized torque signal is then passed to a computer 19 which has been programmed to analyze the signal and produce an output indicating variation of torque with time, for example by sampling the torque signal for a succession of short periods. The signal is preferably sampled at a rate of at least 300 Hz.
The computer calculates the mean square torque for each sampling period, and FIG. 2 shows the values of mean square torque for a number of successive samplings over a broad frequency range. This figure demonstrates the difficulty of detecting torsional vibration of the bottomhole assembly by this method.
During the test shown in FIG. 2, the bottomhole assembly itself incorporated a downhole sensor to detect torsional vibration of the bottomhole assembly directly. Signals from the downhole sensor were stored in a memory, also located downhole, and the contents of the memory were analyzed after completion of the test and withdrawal of the drilling system from the hole. The results of the downhole readings of torsional vibration were then superimposed on the surface readings of mean square torque for comparison purposes. In FIG. 2 the surface readings taken at times when the bottomhole assembly was actually experiencing torsional vibration (as detected by the downhole sensor) are shown in solid black. It will be seen that the peak levels of mean square torque, measured at the surface, do not necessarily occur at times when torsional vibration was occurring downhole. Thus, when total mean square torque is calculated for a wide band of frequencies there is no apparent correlation between the readings taken at the surface and the occurrence of torsional vibration of the bottomhole assembly.
Accordingly, taking surface measurements in this way does not allow any inference that a peak in mean square torque for all frequencies, measured at the surface, corresponds to a period of significant torsional vibration downhole.
FIG. 3, however, shows monitoring of the output from the surface torque sensor in accordance with the present invention.
As a first step, physical details of the bottomhole assembly, i.e. parameters such as dimensions, mass rotary inertia, and flexibility of the drill collar sections or other bottomhole components, are fed into a computer program designed to calculate the torsional natural frequencies of the bottomhole assembly, assuming free end conditions. The frequencies for integer wavelength modes are then noted. In the case of the system being tested in FIG. 2 a natural frequency of 18 Hz was noted.
Accordingly, in the plots of FIG. 3, the mean square torque for each surface measurement is calculated only in a narrow bandwidth around 18 Hz, e.g. between 16.5 Hz and 20.5 Hz, and not for a full range of frequencies. In FIG. 3 this value is then plotted against time in the same manner as in FIG. 2, the readings corresponding to bursts of torsional vibration of the bottomhole assembly being again shown in solid black. It will be seen that there is now an evident correlation between peaks in the mean square torque, based on the surface measurements, and the actual bursts of torsional vibration measured downhole. If more frequent samples of the surface torque are taken, then the agreement will be even closer. Accordingly, monitoring the surface torque in this way, i.e. effectively applying a filter of narrow bandwidth around a pre-ascertained reference frequency, allows downhole torsional vibration to be detected at the surface, so that the operator of the drilling system may then take appropriate steps to reduce the downhole vibration, for example by varying RPM and/or WOB, and may see from continued monitoring of the surface torque whether the steps taken have been successful in reducing the downhole vibration.
In a specific method according to the invention, the surface torque sensor 11 supplies an analogue signal to the analogue-digital converter 18 , which supplies a digital signal to the computer, which is fitted with a data acquisition card. As before, the computer is programmed to sample the analogue signal at a rate of at least 300 Hz for successive periods, each of a few seconds. According to one particular method of the invention, the spectral density function is then produced, as shown for example in FIG. 4, which illustrates a typical spectral density function for one sampling period. It will be seen that this shows a spike at around 18 Hz, indicating the presence of some torsional vibration downhole at around that frequency. In order to monitor the downhole torsional vibration, the computer program calculates the area of the spectral density function for a bandwidth of a few Hz, for example about 4 Hz, around the 18 Hz frequency or other reference frequency for an integer wavelength mode of torsional vibration of the particular bottomhole assembly being used. This value may then be plotted on a rolling time axis which may be displayed on a Visual Display Unit (VDU) or print-out to show the system operator any changes that occur with time. By monitoring this visual output, the operator may determine whether torsional vibration is occurring downhole and may see the response to his modification of drilling parameters in an effort to reduce such vibration. All values would be stored in a log for later analysis. One sampling period every few seconds should be sufficient to give the operator ample warning of the onset of torsional vibration.
Appropriate analysis of surface torque may also provide other information regarding downhole conditions. For example, FIGS. 5 and 6 show plots, from measurements taken downhole, of the relationship between RPM and torque during drilling. It will be seen that each plot is generally in the form of a loop indicating an hysteresis effect. It is believed that the oscillatory behaviour of the drilling system which is represented by such plots may be at least partly dependent on the nature of the formation through which the drill bit is drilling at the time. Thus, the plot of FIG. 5 was acquired when the drill bit was drilling through Burgess sandstone whereas the plot of FIG. 6 was derived when drilling softer formation of shale/Burgess sandstone.
FIG. 7 again shows the relationship between torque and RPM, but in this case in a series of tests drilling through different types of formation, the plots for the different tests being superimposed.
The main part of the graph, where the plot comprises a series of loops, as indicated at 21 , the bit was drilling through relatively hard formations such as limestone and sandstone. However, when drilling through shale, a softer formation, the plot of torque against RPM is of an entirely different configuration, as indicated at 22 in FIG. 7 . Here, at about 150 RPM, the torque varies only over a small range at about −500 ft-lb.
The possibility therefore arises of using information regarding the torque vibration of the bottomhole assembly for the purpose of inferring the nature of the formation through which the drill is drilling.
The particular data incorporated in the graphs of FIGS. 5 to 7 generally cannot be obtained from surface measurements. However, it is believed that information as to the nature of the formation being drilled can be obtained from the spectral density function, as shown for a example in FIG. 4 . The characteristics of the spectral density function may be used to indicate the nature of the formation currently being drilled. Monitoring the torsional vibration of the bottomhole assembly from surface measurements, as previously described, may therefore provide a guide as to when the drill bit has reached a payzone.
The invention has been particularly described in relation to the detection of torsional vibration in a bottomhole assembly, and this is where the invention may be particularly useful. However, it will be appreciated that the principle of the invention may also be applied to the detection, at the surface, of vibration in other downhole assemblies or components.
Whereas the present invention has been described in particular relation to the drawings attached hereto, it should be understood that other and further modifications, apart from those shown or suggested herein, may be made within the scope and spirit of the present invention. | The invention provides a method of detecting, at the surface, the occurrence of torsional vibration in a bottomhole assembly mounted on the drill string of a rotary drilling system. The method includes the steps of: ascertaining natural frequencies of torsional vibration of the bottomhole assembly prior to drilling, and noting at least one reference frequency for an integer wavelength mode of torsional vibration of the bottomhole assembly. During subsequent drilling, the drill string mean square torque at the surface is monitored for a bandwidth around the reference frequency. It is found that peaks in the mean square torque, close to the reference frequency, are indicative of the occurrence of torsional vibration in the bottomhole assembly. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. The Filed of the Invention
[0002] The present invention pertains to an improved slag handling system and, in particular, to a system which obviates the use of an expensive and unreliable drag conveyor.
[0003] 2. The Prior Art
[0004] All coal and coke gasification systems must have slag removal systems to discharge the ash and nonvolatile materials which are unavoidable by-products of such processes. One present slag removal system incorporates a slag drag conveyor which receives slag directly from a lockhopper onto a conveyor belt which conveys the slag to a slag containment vessel (such as a truck, train, pit, etc). The slag producing sections of these gasification processes are in a harsh environment exposed to both erosive materials and corrosive chemicals. This harsh environment has caused the drag conveyors, with their many moving parts, to be failure prone, maintenance intensive, and thus unreliable for slag removal. The drag conveyors are very expensive, in and of themselves, and therefor spare or backup systems are too costly to be kept on site for emergency use. The unreliable nature of this type of slag removal equipment can lead to downtime for an entire gasification plant and thereby reduced onstream time/capacity factors. One known drag conveyor was such a major weak link in a gasification process that it was eventually bypassed by using an emergency slag dump line. In order to improve the reliability of gasification processes, an improved method of slag handling, which is environmentally acceptable, economical to maintain and operate, and safe to operate, is necessary.
[0005] Coal-fired boilers in other industries generate ash/slag material which is similar to, but not exactly the same as, the slag which results from gasification processes. However, unlike gasifiers, the slag producing portions of conventional boilers usually do not operate under pressure and therefor can have continuous removal of slag from the system. There are variations of sluicing systems used in these coal-fired boiler plants.
[0006] It is believed that the present invention can overcome at least some of the above discussed problems by significantly reducing unit downtime of coal and coke gasification plants and thereby improve capacity factors for potential customers. It will allow higher onstream times by reducing downtime for maintenance and repair of the slag removal system. The cost of the system should be considerably less than for a drag conveyor system, especially considering that plant maintenance costs will be substantially less.
SUMMARY OF THE INVENTION
[0007] The present invention provides for the removal of slag from a gasification system operated under pressure by using a lock hopper to receive, depressurize and dispense batches of slag. The slag passes through a discharger, where it is ground to sufficiently small size to pass through the rest of the system without causing any jamming. The ground slag is passed to an eductor where it is mixed with water, from a closed loop sluice water system, and sent to a slag pit. The water level in the slag pit is monitored and returned to the closed loop sluice water system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The present invention will now be described, by way of example, with reference to the accompanying drawings, in which the single FIGURE is a schematic diagram of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0009] The subject system 10 is preferably used in conjunction with, and as part of, a known coal or coke gasification plant, of which only the slag receiving sump 12 has been shown. The sump 12 usually has therein grinding means (not shown) to break up the slag it receives from the gasifier operation. The slag handling portion of the subject system has a lockhopper 14 with a first pressure lock 16 connecting the output of sump 12 to the input of lockhopper 14 and a second pressure lock 18 serving for its output. A slag discharger 20 is connected between the second pressure lock 18 and slag grinder 22 , where the slag is ground and reduced in size so as not to plug the downstream equipment. The ground slag is passed through pipe 26 to eductor 24 where it is mixed with water and sent through pipe 28 to the sump pit 30 .
[0010] The system also includes a closed loop sluice water portion in which tank 32 serves as the primary source of sluice water. A sluice water pump 34 is connected to an output of tank 32 and by distribution piping 36 through valve 38 to eductor 24 , valve 40 to discharger 20 , valve 42 back to the tank 32 , and valve 44 to a grey water treatment facility (not shown). Forming the return portion of the closed loop is sump piping 46 having pump 48 connected to the sump pit drain line 50 , valve 52 connected to a return line 54 to the sump pit 30 , and valve 56 to the sluice water tank 32 . Valves 52 and 56 are controlled by sump level sensing and control means 58 . The sluice water tank 32 includes level control means 60 and inlet valve 62 connected to a make up water source (not shown). Valve 44 connects the close loop to a gray water treatment facility (not shown) to grey water to dispose of overly contaminated water. A control 64 controls the operation of the pressure locks 16 , 18 , and valves 38 , 40 , 42 , as described below. The discharger 20 preferably is equipped with a vent 66 connected to vapor recovery means (not shown).
[0011] Slag accumulates in the lockhopper 14 , according to normal gasifier operation, by periodic actuation of pressure lock 16 . The pressure lock 18 is likewise be periodically actuated, but only when pressure lock 16 is closed, to dump the accumulated slag into discharger 20 . Some sluice water is admitted to the discharger through valve 40 and some vapor is discharged through vent 66 . The discharger then discharges the partially cooled and depressurized slag to slag grinder 22 where it is reduced in size sufficiently so as to not cause clogging problems downstream. Ground slag is then be fed to the sluicing water eductor 24 where it is mixed with sluice water and hydraulically transferred to the slag pit 30 .
[0012] The slag pit 30 is constructed to promote efficient dewatering of the slag. Slag pit water will be pumped by pump 48 through piping 46 to sluice water tank 32 , where residence time can be provided for solids settling. High volume pump 34 provides sluice water through valve 38 and the eductor 24 to the slag pit 30 .
[0013] Level control system 58 maintains a minimum water level in the slag pit 30 by selectively actuating valves 52 and 56 and pump 48 . Level control system 60 maintains a sufficient quantity of water in the sluice water tank 32 , by actuating valve 62 , to assure a full slag dump cycle.
[0014] The total closed loop sluice water system preferably is sized to maintain a water balance. Occasional excess water is passed to a grey water treatment system (not shown) through valve 44 .
[0015] The discharger 20 is a commercially available piece of equipment and a suitable example is the Roplex Discharger manufactured by the Hindon Corporation of Charleston, S.C. It is designed with a unique internal configuration and a bottom dump rotary plow which provides uniform discharge feed and eliminates vessel plugging. The discharger 20 discharges into slag grinder 22 which reduces slag size to dimensions which will not plug downstream equipment in the path to the slag pit 30 .
[0016] The slag pit will preferably have multiple slag entry points. When a section of the pit becomes full, an alternate entry location will be selected and opened. The pit will be designed for efficient dewatering of the slag piles. After a predetermined period, to allow for additional dewatering, the dewatered slag can be loaded into trucks and hauled off site.
[0017] The low end of the slag pit will collect water runoff from the incoming slag. The slag pit water pump 48 pumps the water from the slag pit sump to either recirculate it to the pit through valve 52 or to the sluice water tank 32 through valve 56 . System design should enable the slag water pump 48 to run continuously to reduce on/off operation pump stress and to prevent solids from settling in the lines 46 , 50 , 54 and pump 48 . If the sump level becomes low, the slag pit sump level control 58 will open the water return valve 52 and close the water valve 56 to the sluice water tank 32 to maintain the minimum sump level required to prevent loss of suction to the pump 48 . If the sump level drops below a low-low level point, the pump 48 will shut down.
[0018] The sluice water tank 32 normal operating range will provide adequate water supply to sustain the sluicing system through a complete slag lock hopper dump cycle. A level control system 60 will maintain the proper level in the sluice water tank, providing make-up water through valve 62 during low level conditions and rejecting excess water through valve 44 to a grey water treatment system (not shown) during high level conditions. The tank 32 will provide residence time for additional solids settling. This will help to protect the downstream, high volume, sluice water pump 34 and the slag eductor 24 from unnecessary erosion. Solids settling will also provide a cleaner source of water for rejection to the grey water system. Accumulated solids will need to be cleaned out periodically, or a cone bottom tank can be used incorporating a solids removal system. If the closed sluice water system requires chemical additions for water quality, the tank 32 will provide a suitable injection/mixing point.
[0019] The sluicing water control valves 38 , 40 , and 42 will operate in conjunction with the interlock/timing system of the lock hopper 14 . When the lock hopper 14 is in the collect mode, the sluice water valve 38 to the slag eductor 24 and the flush water valve 40 to the slag tank 20 will be closed. Sluice water return valve 42 to the tank 32 will be open. System design should enable the sluice water pump 34 to run continuously to reduce on/off operation pump stress and to prevent solids settling in the lines and pump. When the lock hopper 14 completes the depressurization step, valve 38 will open to provide sluice water to the system and valve 42 will close. The flush water valve 40 will open to allow the necessary flush of water to the discharger 20 . This flush will help slag move through the discharger 20 , through the slag grinder 22 and into the eductor 24 . At the completion of the sluicing cycle, a timing control system will open valve 42 and close valves 38 and 40 .
[0020] The present invention may be subject to many modifications and changes, which will become apparent to one skilled in the art, without departing from the spirit or essential characteristics thereof. Thus the above described embodiment should be considered in all respects as illustrative and not restrictive of the scope of the present invention as defined by the appended claims. | A batch slag handling system for gasifiers and the like which operate under pressure, has a lockhopper receiving the slag under pressure and dispensing it after depressurization. The slag is ground and combined with water for transport to a slag sump where it is dewatered and then removed from the site. Sluice water is provided by a closed loop system. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to fasteners and is more specifically related to internally threaded fasteners having self locking patches of thermoplastic material adhered to at least a portion of the threads thereof.
Self-locking fasteners of the type in which the self-locking characteristic is derived from a coating such as a patch material adhered to all or a portion of the thread defining surface of the fasteners have proven to be very popular for a wide variety of applications, in order to prevent loosening of the fastener due to vibration and the like in various applications. The prior art discloses various methods and apparatus for applying locking patches of resilient resin or thermoplastic type material to threaded articles. Many of these teachings, however, have proven to be effective only for coating externally threaded fasteners with patches of resilient material and do not find application when it comes to applying such patches on internally threaded fasteners to make them self-locking. To attempt to utilize many of these continuous powder feed type systems with internally threaded fasteners would result in the unwanted coating of surfaces other than the threaded portion of such fasteners.
The problem of providing a coating that will act as a self-locking element to the threads of an internally threaded article such as a nut has presented many difficulties. Such an article may be a friction nut capable of producing a fluid tight seal or the like. A suitable coating for this purpose may be any of numerous resins, such as nylon or other thermoplastic resins. Prior art references that have addressed the problem of forming self locking patches on internally threaded fasteners, have frequently required heating of the fastener to at least about 450° F., prior to directing the thermoplastic material towards the threads to form the self-locking patch.
To insure proper adhesion of the thermoplastic material to the threads with these types of processes, it was also necessary to include an epoxy resin component in the material. Since the entire fastener was preheated to a temperature significantly above the melting point of the thermoplastic resin, great care was required to be used in order to insure that the thermoplastic resin came into contact only with the precise portion of the internal threads of the fastener that was desired to be covered and nowhere else. Otherwise, upon application the resin would tend to adhere to other surfaces of the fastener, causing cosmetic problems, overspray and also improper and inconsistent torque values for the finished self-locking product.
To overcome this problem, various, rather complicated devices were developed. Some devices interrupted the stream of thermoplastic material at regular intervals or indexed the flow of material to coincide with a succession of fasteners passing by the powder supply station. Other systems have utilized special nozzles that were at least partially inserted into the openings of the internally threaded fasteners on a reciprocating basis, to attempt to more precisely control the deposition of powder onto only the desired number of threads and about a desired circumference. Many of these prior art devices also required a large number of powder supply tubes or nozzles in order to provide a separate nozzle for each internally threaded fastener to be coated, such as taught in U.S. Pat. No. 4,366,190. This became particularly troublesome, considering that these systems traditionally required the powder to be entrained in an airstream in order to be directed towards the fasteners.
An additional drawback to such methods and apparatus was presented as a result of the use by these systems of a recirculating powder feed system. Whatever excess thermoplastic powder was directed towards the internal threads of the fastener that did not adhere thereto was frequently, entirely or partially melted as it passed by the highly heated fastener. This resulted in particles fusing together and being recirculated into a powder feed system and then potentially agglomerating even further with other particles. This caused an uneven powder flow of particles of different size, diameter and character to be directed towards subsequent heated fasteners. This resultant variation, combined with pulsing of the airstream entrained powder flow, due to agglomeration of the powder from moisture or the presence of other contaminants, lead to significant variations in torque values of the self locking fasteners and also a shortened useful life of the powder that was recirculated.
Certain disadvantages have also been experienced with other known methods and apparatus to form resilient thermoplastic patches on internally threaded fasteners that do not require the fasteners to be heated prior to application of the patch material. For example, U.S. Pat. No. 4,262,038 discloses a method of producing coated internal threads of a fastener that is only capable of producing a 360° coating and necessitates completely filling the internally threaded opening of the article throughout the complete 360° circumferential extent thereof between the ends, with the thermoplastic resin prior to heating the fastener. This method is slow since it requires the entire cavity of the internally threaded fastener to be filled with powder, even though the vast majority of the powder is not utilized in the coating. Also, this method does not provide for formation of a patch that would either be less than 360° in circumference, or cover fewer than all of the threads of the fastener.
Other prior art systems that do not heat internally threaded fasteners prior to the deposition of the resilient powder present other shortcomings. The system taught in U.S. Pat. No. 3,830,902, requires each fastener to be coated to be placed upon a pin which masks a greater portion of the thread defining surface and establishes a cavity which permits the deposit of plastic powder upon a limited portion of the threads, resulting in the establishment of a plastic patch of limited axial and circumferential extent. These pins require a certain amount of spacing between each successive pin in order to properly position and remove the nuts. It was found that the use of pins upon which fasteners are seated during establishment of plastic patches on the fasteners in such systems was problematic. The pins would wear allowing uncontrolled distribution of powder upon the thread defining surface, even to the extent that the desired clear lead-on thread had not been preserved.
In addition, the limited circumferential extent of a plastic patch produced by such systems provides only a concomitant limited area of adherence between the patch and the threads of the fastener. Thus, where the presence of foreign matter such as water or oil at the interface between the patch and thread defining surface tends to come between the patch and the area of the surface to which the patch adhered, total adherence is diminished sometimes to an unacceptable level. These systems also required use of a powder distribution means that had a continuous flow that had to be indexed with the fasteners travelling thereunder to provide for powder flow only when the threaded surface of the fastener passes below the powder distribution means.
While the prior art systems, referred to above, have proven to be at least somewhat successful in achieving the objects for which they were intended, it has become desirable to have an improved method and apparatus which offers equal or superior speed and quality over existing systems for applying resilient self locking patches to internally threaded fasteners that does not require preheating of the fasteners prior to application of self locking materials, indexing of the fasteners, indexing or interruption of the powder stream to the fasteners, multiple, intricate or reciprocating nozzles for powder deposition, an airstream to be combined with the powder delivery system or the use of powders that have a resin included therein.
While the present invention will be described particularly with respect to applying heat softenable thermoplastic particles to the threads of internally threaded articles, it is to be understood that apparatus and process of the present invention can be used to apply a variety of materials, including resins and resin compounds and pure nylon.
It is therefore an object of the present invention to provide an improved method and apparatus for the manufacture of self locking internally threaded elements wherein the self locking feature is obtained through a thermoplastic deposited onto a selected portion of the internal threaded surface of the element.
Another object of the present invention is to provide an improved method and apparatus for the manufacture of self locking internally threaded elements wherein improved control of the application of the locking body of thermoplastic and thermoplastic application is obtained over a desired arcuate and vertical area of the internal threads of the element and preheating of the fastener is not required.
Yet another object of the present invention is to provide an improved method and apparatus for the manufacture of self locking internally threaded elements wherein the powder flow through the output of the powder delivery system to the elements is continuous and uninterrupted.
Still another object of the present invention is to provide an improved method and apparatus for the manufacture of self locking internally threaded elements that achieves substantially equal results in terms of locking ability regardless of whether the powder used is a resin or has an epoxy constituent.
A further object of the present invention is to provide a method and apparatus for the manufacture of self locking fasteners that allows for greater reusability and more economical use of coating powder.
A still further object of the present invention is to provide a method and apparatus for the manufacture of internally threaded self locking fasteners that utilizes a continuously moving conveyor belt with the internally threaded fasteners delivered onto the belt such that one of the external faces of the nut is in substantially complete contact with the upper surface of the conveyor belt and a portion of one of the sides of the nut is also supported.
SUMMARY OF THE INVENTION
The above objects and other objects which will become apparent after a reading of the detailed description of this invention are achieved by a method for applying a locking element of thermpolastic type material to a succession of internally threaded articles having open ends to the threaded portion thereof that includes the steps of conveying the threaded articles on a support in a path for treatment with the axes of their threaded portions in a substantially horizontal position and with their openings at the threaded protions uncovered, directing a continuous uninterrupted stream of thermoplastic type material onto and around an area of each of the threaded portions in an amount in excess of the amount needed to form the locking elements, removing the amount of thermoplastic type material in excess of the amount required to form the locking element from around the area of each of the threaded portions and from the threaded portions of each of the articles, and thereafter heating the threaded portions of the threaded articles to a temperature above the softening point of the thermoplastic type material to be applied.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an embodiment of an apparatus for the manufacture of self locking internally threaded fasteners in accordance with the present invention.
FIG. 2 is a fragmentary perspective view of a portion of the path that fasteners travel in accordance with one embodiment of the present invention.
FIG. 3 is a fragmentary top view of a portion of the path that fasteners travel in accordance with one embodiment of the present invention.
FIG. 4 is a partial cross sectional view of a single fastener as it passes through the powder applicator of the present invention.
FIG. 5 is a partial cross sectional view of a single fastener as it passes through a powder removing airstream of the present invention.
FIG. 6 is a partial cross sectional view of a single fastener as it passes through a powder removing suction device of the present invention.
FIG. 7 is a plan view of a threaded fastener shown in the form of a nut constructed in accordance with the teachings of the present invention.
FIG. 8 is a cross sectional view taken along the line 8--8 of FIG. 7.
FIG. 9 is a cross sectional view taken along the line of 9--9 of FIG. 7.
FIG. 10 is a diagrammatic view of the path of the recirculating powder feed system in accordance with an embodiment of the present invention.
FIG. 11 is a top view of the powder feeder and powder sensor of the present invention.
FIG. 12 is a partial cross sectional view of the powder feeder of the present invention taken along the line 11--11 of FIG. 12.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, and in particular FIGS. 7-9, a typical internally threaded fastener is illustrated that has been processed in accordance with the apparatus and methods of the present invention. This fastener 12, is illustrated as exemplary of only one of the many different types of internally threaded fasteners that could be processed in accordance with the present invention and has six external sides 15 and two opposing faces 17. The fastener 12 also has internal threads 13 and a self-locking patch 14 of applied resilient material 38. In accordance with the present invention, this patch 14 can be accurately positioned and deposited on a selected number of threads 13 of a fastener 12 along a selected arc and at a selected thickness more economically, quickly and accurately than existing methods and apparatus for forming such patches on internally threaded fasteners. It should be noted that, as illustrated in FIG. 8, patch 14 when adhered to a selected number of threads 13, is thicker in the region of the thread valleys 29 than in the area of thread crests 21 and tends to loosely follow the contour of the threads 13.
Referring now to FIG. 1, the apparatus 10 of the present invention is generally disclosed. The apparatus 10 includes a continuous conveyor belt 20 that is preferably constructed of a material that is capable of withstanding significant repeated exposure to heating, such as fiberglass. The belt 20 is wider than the width of one of the external sides 15 of the fasteners such as fastener 12 that can be processed in accordance with the present invention. The belt 20 is driven by a belt drive system that features conveyor systems 24 and 26 that continuously circle the belt 20 at an adjustable preselected speed preferably on the order of 10-20 feet per minute, in accordance with the self-locking processing to be completed by the apparatus 10.
As illustrated in more detail in FIGS. 1-6, during all times that fasteners 12 are present on the belt 20, at least a portion of one of the external sides 15 of each fastener 12 is in contact with the surface of the belt 20. Also, during the entire time that fasteners 12 are in contact with the belt 20, at least a portion of the outer face 17 of each of the fasteners 12 is in contact with the guide bar 64. The guide bar 64 provides a slick heat resistant surface to support and orient the fasteners 12 that are to be processed. The guide bar 64 is preferably of a height equal to or greater than the height of fasteners 12 to be processed, measured from one outer face 15 to a 180° opposing outer face 15. The guide bar 64, as previously mentioned, must provide a non-stick heat resistant support surface for the fasteners 12. Although a variety of materials are suitable for construction of the guide bar 64, it has been found particularly preferable to utilize a fiberglass or fiberglass reinforced material with a Teflon coating to achieve superior results.
As particularly illustrated in FIGS. 3-6, guide bar 64 is spaced horizontally a distance from the conveyor belt 20. The space 54 between the guide bar 64 and the conveyor belt 20 is at its minimum, as indicated at W1 in FIG. 3, at a point where fasteners 12 are first introduced onto the conveyor belt 20. The space 54 between the guide bar 64 and conveyor belt 20 then continuously increases to a maximum spacing or width as represented at W2 in FIG. 3, which is in the region where fasteners 12 processed with self-locking patches 14 in accordance with the present invention are exited from the conveyor belt 20 for the purpose of collection.
Device 10 is also provided with a belt rail 86 which runs substantially the entire length of the conveyor belt from the region where resilient thermoplastic material 38 is applied to the fasteners 12 to the region where the fasteners 12 are exited off of the conveyor belt 20. The belt rail 86 serves to shield the drive means of conveyor belt 20 from resilient thermoplastic material 38 and further serves to shield the belt 20 from the operator.
The improvements of the present invention are more readily appreciated by tracing the path of fasteners through the apparatus 10. Fasteners 12 are required to be presented to the conveyor belt 20 in a uniform closely spaced manner. Any of a number of different known types of parts feeding mechanisms, such as vibratory parts feeder 16, can be used to accomplish this purpose. The feeder 16 arranges and moves fasteners in a manner to deposit them continuously and uniformly onto the orienting track 18. Fasteners 12 are first deposited onto the orienting track 18 in a closely spaced continuous fashion with one of the fastener surfaces 17 resting against the bottom 33 of the orienting track 18. As the fasteners 12 move down the orienting track 18 towards the conveyor belt 20, the fasteners 12 are rotated to a different orientation such that they are substantially resting on one of the fastener outer faces 15. The fasteners 12 then pass under guide roller 22 and are thereby urged onto the conveyor belt 20 such that a portion of one of the outer faces 15 of each fastener 12 is in contact with the top surface 19 of the conveyor belt 20 and a portion of one of the surfaces 17 of each fastener 12 is in contact with the guide bar 64.
When the fasteners 12 are first introduced onto the conveyor belt 20 and are moved into the region of the powder delivery chute 62, they continue to be in a substantially upright orientation wherein all of one of the outer faces 15 of each fastener 12 is either in contact with or very close to the top surface 19 of the conveyor belt 20 and the fastener opening 25 is substantially parallel to the top surface of the conveyor belt 20. This orientation can be readily seen with reference to FIGS. 3 and 4, wherein the angle a1 is very small. The preferred range of values for the angle a1 is between about 1° to 20°.
The increase in the size of the gap 54 as the fasteners 12 traverse the length of the belt 20 causes a slight rotation of the fasteners 12 due to an increase in the value of angle a1 first to a2 and then ultimately to a3 as indicated in FIGS. 4-6. The preferred range of values for the angle a3 is between about 10° and 30°. As best illustrated in FIGS. 2 and 4, as fasteners 12 move along the conveyor belt 20 and pass in front of the powder delivery chute 62 each fastener 12 encounters a continuous flow of powdered resilient thermoplastic material 38 that is deposited around, on and in a circumferential portion of the threads 13 of each fastener 12 in an amount greater than that required to form the desired patch 14 of resilient thermoplastic material 38.
As previously mentioned and as will be discussed hereafter in much greater detail, the powdered resilient thermoplastic material 38 is deposited onto a portion of the threads 13 of each fastener 12 from the powder delivery chute 62, without the necessity of the material 38 being combined with or entrained in an airstream. Rather, the powder material 38 is delivered down the powder delivery feeder pipe 60 from the powder feeder exit area 58 under the force of gravity alone. It is preferred that the exit end of the delivery chute 62 be positioned such that the delivery of powder material 38 onto the threads 13 of the fasteners 12 is angled. It has been found that powder delivery has been best when angles of the chute 62 and delivery of the powder material 38 are close to 45° to the outer face 15 of the fastener 12 that is in contact with the top of the conveyor belt 20. The chute 62 is constructed so that its angle of delivery of powdered material in relation to the outer face 15 of the fastener 12 passing by it can be adjusted depending upon the processing that is desired.
As the fasteners continue their traverse down the conveyor belt 20, they next encounter one or more airstreams designed to shape and position the powdered resilient thermoplastic material 38 in an amount and in a way to produce the desired resilient thermoplastic patch 14 on the threads 13 of the fasteners 12 and remove. These airstreams also serve to recirculate all excess powdered resilient thermoplastic material 38 that was initially deposited to allow it to be ultimately delivered to other fasteners 12.
It should be understood that the embodiments illustrated of various airstream configurations to be used in positioning and shaping the material 38 and removing the excess material 38 are only exemplary and that more or fewer airstreams could be used and their orientations could be changed. The airstreams used could also be either all air blowing or all air vacuum streams or a combination thereof and still be within the scope of the present invention. Additionally, the present invention also contemplates locating one or more airstreams in front of or behind the belt 20, on top of or below the belt 20 and/or at any angle to the belt 20. Given this, the particular embodiment illustrated in FIGS. 1-6 will now be described in detail.
As illustrated in detail in FIGS. 2 and 5, an airstream issuing from a device such as a nozzle 68 is used for removing all powder from the lead thread as is required in many specifications for applying the patches 14 to fasteners 12. In addition, when angled properly, the airstream issuing from the nozzle 68 can be quite effective in removing the powdered material 38 from unwanted areas such as the fastener surfaces 17 and the conveyor belt 20. By acting in conjunction with a vacuum system stray material 38 and material 38 moved by the airstream is drawn into the vacuum nozzle 78 and then the powder return tube 84. In this manner, the excess material 38 can then be recirculated for ultimate deposition onto additional fasteners 12.
As illustrated in FIGS. 3 and 5, as a result of this slight rotation of the fastener 12 on the conveyor belt 20 to the angle a2, it becomes easier to direct an airstream, such as that supplied by nozzle 68, to clear the lead thread of the fastener 12. This rotation also assists in clearing the areas of the conveyor belt 20 that are not in contact with the fastener 12. The clearing of the belt 20 is further accomplished by an additional airstream issuing from tube 79 in which thermoplastic material 38 dislodged by the airstream issuing from the tube 79 is collected for recirculation by vaccum nozzle 78 located on the opposite side of fastener 12 from tube 79. Both nozzle 68 and tube 79 can be of any standard design and could be either rigid or flexible. Preferred constructions include 1/8" copper tubing, nozzles having a single slotted opening, nozzles having a face perforated with a plurality of small openings and open ended flexible plastic tubes. Nozzle 68 and tube 79 are movably attached to apparatus 10 to allow for easy removal or adjustment depending upon the type of fasteners to be processed.
Once the fastener 12 has passed the airstream issuing from tube 79, it then encounters another airstream, such as that supplied from air vacuum 70. As the fasteners travel along conveyor belt 20 and encounter the air vacuum 70, they are rotated further on the conveyor belt 20, to the increased angle designated as a3 in FIG. 6. The rotation of the fastener 12 to the angle a3 allows for a relatively easy removal of excess powdered material 38 from the conveyor belt 20 and fastener surfaces 17 and outer faces 15. Alternatively this angle of rotation of fastener 12 also allows for removal and shaping of the material 38 in the area of threads 13 without disturbing the powder material 38, at the desired location of the threads where the patch 14 is to be located. Air vacuum 70 is utilized to remove powder from a region parallel to the nozzle, as illustrated in FIG. 6. The force of flow through air vacuum 70 is controlled by air vacuum control 52. Although a variety of different air pressures can be used to create a vacuum, the most preferred ranges of air pressure have been found to be on the order of approximately two inches of mercury.
As illustrated, air vacuum 70 can be used in conjunction with another vacuum system that directs stray powder material 38 into vacuum nozzle 88 and recirculating tube 90, for ultimate redeposition onto additional fasteners 12. Likewise, the powder material 38 that is removed with by air vacuum 70 is recirculated for ultimate redeposition onto additional fasteners 12.
Once the fasteners 12 leave the area of air vacuum 70, they continue along the conveyor belt 20 and pass through a heater 72. By the time of entry into the heater 72, only the powdered material 38 that is necessary and desirable to form the desired patch 14 remains in the area of the threads 13 of each fastener 12, and substantially all of the excess powdered material 38 that was initially deposited and, either on or around the fastener 12, has been removed and recirculated.
As the fasteners 12 traverse along the conveyor belt 20, through the heater 72, the fasteners are raised to a temperature sufficient to cause the powdered material 38 to adhere to the threads 13 of the fasteners 12 and to be fused by heat from the threaded surface 13 to form a continuous plastic body thereon. In order to cause sufficient adherence of the material 38, it is preferable to use the heater 72 to raise the temperature of the fasteners 12 above the melting point of the material 38. A preferred way of accomplishing this is by use of a high frequency 200 kilohertz induction heater. Although this heater is most preferred, those of a 30 kilohertz frequency or higher are sufficient in most instances to produce a suitable amount of heat. Once the fasteners 12 exit the heater 72, they begin to cool and are exited off of the conveyor belt 20 using any of a number of known parts removal systems, such as the one illustrated at 76.
The present invention necessitates a lesser degree of heating than prior art processing systems that directed powdered thermoplastic material against fasteners that had been preheated to a temperature sufficient to cause the material to adhere to the threaded surface of the fasteners. This is because in the present invention all of the thermoplastic powdered material that will ultimately form the patch is already deposited and resting in the threaded area of the fastener prior to heating of the fastener. The heat applied thereafter need only be great enough to cause the thermoplastic powder to adhere to threads of the fastener and coalesce and fuse the material to form a continuous plastic body.
In contrast, prior art systems required increased heating of the fasteners to enable not only adherence and fusing of the material into a continuous plastic body, but also the initial catching and softening of individual particles from a stream of the particulate material that was directed toward the threads of the fasteners. Since the present invention does not have to catch particles from a stream directed toward the threaded surfaces of fasteners it also either substantially lessens or in some cases eliminates the need for a primer or tying agent such as a thermosetting epoxy resin powder to be combined with the thermoplastic particles of the locking element. This results in a significant potential cost savings without sacrificing adherence and torque values of the finished patch.
The unique powder feed system of the present invention will now be described in more detail. Referring to FIGS. 1, 2, 10 and 11, powdered material 38 is contained in the powder supply bin 42 and is exited from the powder block 36 by auger 40 that urges powder material 38 out through an opening in the block 36. The auger 40 is rotated in response to the optical sensor assembly 30, which is connected to the powder block 36 and is positioned partly within the vibratory powder feeder 28.
The optical sensor arm 34 holds and connects the optical sensor 32, which extends into the vibratory powder feeder 28. The optical sensor 32 is directed toward the bottom 56 of the powder feeder 28. If the optical sensor 32 senses that an insufficient amount of powdered material 38 is present in the bottom 56 of the feeder 28, then it causes the auger 40 to move in the powder block 36 and force more powdered material 38 to drop into the bottom 56 of the feeder 28. The sensor 32 provides very precise control over the amount of powdered material 38 in the bottom 56 of the feeder 28 in order to keep the level virtually constant. Although many different photoelectric sensors can be used, a particularly preferred sensor, for the purposes of this invention, was found to be an OMRON photoelectric switch (Model E3A2-XCM4T).
The vibratory powder feeder 28 is of a stepped construction, in the nature of an inside track cascading vibratory bowl. The feeder 28 is vibrated and controlled by a variable speed DC motor such as an FMC Centron controller. As illustrated in FIGS. 11 and 12, the vibratory action of the motor upon the feeder 28 causes powder material 38 deposited initially at the bottom 56 of the feeder 28 to move upwardly along the entire length of a track 47 having a bottom 46 and an inner wall 48. The track 47 begins at the bottom 46 and extends in a spiralling manner to the top of the feeder 28 into the powder feeder exit area 58. As best illustrated in FIG. 12, the track 47 is angled slightly toward the inner wall 48 so as to keep the powder material 38 on the track 47 moving toward the powder feeder exit area 58.
The flow of powder material 38 from the feeder 28 can be regulated by varying the rate of vibration of the feeder 28 alone or in combination with an optional flow rate control device. An example of such a device consits of a deflector 97 adjustably attached to a boss 93 in the exit area 58 of the feeder 28 by a screw 99. Both the height and the angle of deflector 97 in relation to the track 47 are adjustable. Deflector 97 serves to limit the flow of material 38 vibrated along the track 47 to the exit area 58. Deflector 97 accomplishes this by directing substantially all of the material that extends above the bottom of the deflector 97 onto the slide 95. Slide 95 is secured to the inside of the feeder. The slide 95 then guides material 38 deposited thereon to the bottom 56 of the feeder 28 in order to again be vibrated along the track 47 to the exit area 58. The remaining material 38 that passes by the deflector 97 then drops down the powder feeder delivery tube 60 and down the powder delivery chute 62 under the force of gravity alone, to be deposited onto fasteners 12 as previously described in detail.
The powder feeder delivery tube 60 can be a standard pipe that allows a narrow path of delivery to the powder chute 62 and is wide enough so as to be connected to and accept and direct all of the powder material 38 leaving the powder exit area 58, down the tube 60 without impediment. A 1/8" thick copper tube has been found particularly useful for this purpose. The adjustable powder chute 62 is connected to the end of the tube 60 furthest away from the powder exit area and can be made of any rigid material and preferably has a smooth surface or has been treated with a non stick material in order to allow free fall of the powder material 38 onto fasteners 12. The width of the chute 62 may vary with the most preferable chutes being on the order of one to three inches wide.
This unique powder feed system affords several advantages to the present invention. It has been found that, for example, if the powdered material that is used is Nylon 11, that the vibratory action of the feeder 28 that the material 38 encounters along the entire spiralling track 47 from the bottom 56 to the top of the feeder 28 tends to substantially keep the material 38 from agglomerating. In addition, this action also tends to separate substantially all of the particles that may have joined together as a result of the presence of foreign materials on the surface of the particles or other reasons by the time the material 38 exits the feeder 28.
As a result, the powder exited from the feeder 28 through the chute 62 onto the fasteners does not require a combination with an airstream, as do most prior art systems of this type. In addition, a particularly uniform flow of powder is maintained, virtually eliminating the pulsing action found in many prior art recirculating powder systems that require an airstream to be combined with the powdered material. A more uniform and consistent application of powdered material 38 to the fasteners 12 is thereby accomplished leading to more economical efficient patch application and powder utilization.
Powder flows in accordance with the present invention are in the range of 80-400 grams/minute with the most preferred range being around 350 grams/minute. The powder feed system of the present invention affords yet another advantage over the prior art systems. The powder application and the ability to locate material 38 on the threads 13 of fasteners 12 prior to heating has been found to be so consistent so as to allow a cost savings through elimination of some or all of the epoxy minor constituent used in most nylon powder coating systems without a substantial reduction in terms of adherence and torque values of the patch 14 formed on fasteners 12. Additionally, it should be understood that the thermoplastic material 38 used in conjunction with the present invention could be any type of thermoplastic including nylon, nylon epoxy resins and Teflon compounds.
As illustrated in FIG. 10, the powder feeder 28 and powder supply bin 42 form two important parts of the recirculating powder system 96 of the present invention. As previously described, the powdered material 38 is applied to fasteners 12 through chute 62 in an amount in excess of that required to form the desired patch 14. At each point along the conveyor belt 20, where excess powder material 38 is removed, such as through nozzle 78 and tube 82, nozzle 80 and tube 84 and tube 73, the powdered material 38 is directed into the powder recirculation conduit 92. The powdered material 38 is then directed from the conduit 92 into a recirculating powder supply 44 where it is combined with powder material 38 that has not previously been recirculated and is supplied through a recirculating powder connector 94 to the powder supply bin 42 for ultimate deposit into the bottom 56 of the feeder 28. This recirculating powder system 96 allows for efficient and economical usage of powder.
In addition, since in accordance with the present invention, all material 38 is applied and excess material is removed prior to any application of heat to the fasteners 12, none of the material 38 that is recirculated or ultimately applied is ever in a previously melted state or fused by heat to other powder particles prior to formation of the patch 14. Likewise, when heated plated fasteners commonly exude smoke that contains moisture and oil. Since the vacuum nozzles of the recirculating powder system of the present invention remove powder from unheated fasteners, the nozzle and powder system do not ingest any moisture and oil filled smoke into the powder system. This leads to an improvement in both resuability and the consistency in quality of the powder flow of the present invention to the fasteners 12. Although the recirculating powder system described above is particularly preferred it should be understood that other recirculating systems such as using the conduit 92 to direct material into a separate bin that is then manually deposited into the powder supply bin 42 at regular intervals could also be used.
The following examples are given to aid in understanding the invention and it is to be understood that the invention is not limited to the particular procedures or other details given in the examples.
EXAMPLE 1
Zinc plated flange nuts, 3/8"-16 were deposited with at least a portion of one of the faces of the nut resting on the conveyor belt as shown in FIG. 3 with the bottom of the threaded surface being substantially parallel to the belt. The belt speed was 13.25 feet/minute resulting in the nuts being fed at approximately 160 pieces/minutes. The nuts were introduced onto the belt at an initial angle between 10° to 12° from vertical with the spacing between the belt and the guide bar being 0.210 inches. The powder supply was adjusted to 100 grams/minute of a mixture of approximately 90% nylon powder and 10% of thermosetting epoxy resin having the following particle size distribution:
10% less than 78 microns
50% less than 165 microns
90% less than 287 microns
mean=174 microns
The powder used was nylon 11 sold under the tradename of Duralon JM by Thermoclad, Inc. As the nuts moved along the belt the spacing between the belt and guide bar increased to 0.260 inches and the angle of the nut to the belt was approximately 15° to 20° from vertical. The powder was delivered to the nuts from the powder chute at approximately a 45° angle. As the nuts continued down the conveyor belt, they encountered eight nozzles, four of which were vacuum nozzles utilizing two inches of mercury and four of which were blow-off or affirmative air flow nozzles utilizing approximately 40 psi of air pressure. The location of the nozzles was as set forth below in order of their upstream to downstream location, along with an indication of whether they were in front of or behind the fastener traveling down the conveyor:
1. lower belt vacuum slotted nozzle (front underneath)
2. upper belt blow-off--nozzle with rows of 132 inch holes (front)
3. parts blow-off--1/8" copper tube (front).
4. upper belt blow-off underside of belt--1/8" copper tube (front)
5. last thread vacuum--1/8" copper tube (front)
6. nut face vacuum--1/8" copper tube (front)
7. lead thread vacuum--1/8" copper tube (rear)
8. lower belt blow-off--1/8" copper tube (front)
Once the excess nylon material was removed and remaining material was shaped, the nuts were passed through a 15 kilowatt induction heater set at 200 kilohertz (88% setting) and the nuts were raised to a temperature of approximately 620° F. it was observed that the nylon material was fully softened and melted resulting in adherence and coalescing of a plastic body in the form of a patch on the bottom of the threaded hole with approximately 60° to 75° of circumferential coverage of three threads. After cooling the applied coating was found to be uniform and to follow the contours of the threads effectively. Torque tests then were carried out with 3/8"-16 bolts The "First on", "First off" and "Fifth removal" torque values expressed in inch pounds are set forth below:
______________________________________First on First off Fifth removal______________________________________1. 79 58 192. 95 62 223. 94 64 294. 98 79 305. 94 81 21______________________________________
EXAMPLE IX
A second group of zinc plated flange nuts 3/8"-16 were deposited with at least a portion of one of the faces of the nut resting on the conveyor belt as shown in FIG. 3 with the bottom of the threaded surface being substantially parallel to the belt. All of the parameters set forth in Example I were identically reproduced except that the powder coating material used was a substantially pure nylon powder that contained a small amount of titanium dioxide pigment. The powder mixture contained no epoxy resin. The powder had the following properties:
POWDER PROPERTIES
at least 99% less than 90 microns 100% less than 250 microns
COATING PROPERTIES
______________________________________Specific gravity 1.04Melting point, DSC Peak 186-188° C.,Abrasion Resistance, 5-8 Mg.Tabor 1000 Cycles,1 Kg. load,CS17 wheelsImpact resistance, Gardner No failures160 in.-lbsSalt spray, ASTM B117 >1000 hours______________________________________
The powder used was French Natural ES Nylon 11 coating powder sold by Elf Atochem North America, Inc. Similar results in terms of appearance, melting, adherence and coalescing of a plastic body in the form of a patch on the bottom of the threaded hole of approximately 60°-75° of circumferential coverage of three threads in comparison to Example I were observed. Similarly, after cooling, the applied coating was found to be uniform and to follow the contour of the threads effectively. Torque tests were then carried out with 3/8"-16 bolts The resulting "First on", "First off" and "Fifth removal" torque values expressed in inch pounds are set forth below:
______________________________________First on First off Fifth removal______________________________________1. 76 57 252. 92 70 203. 78 52 214. 84 66 255. 71 64 22______________________________________
The resulting torque test values on nuts that utilized the substantially pure nylon coating powder compared quite favorably to the torque tests values on nuts from Example I that utilized the nylon powder that contained a 10% epoxy resin constituent.
From these examples, the use of different types of coating powders in connection with the powder feed system, conveyor, heating and air nozzle configurations of the present invention was demonstrated to produce very effective results. | A self locking internally threaded fastener and an apparatus and process for making such fasteners, in which the self locking characteristic is derived from a patch of thermoplastic material having a circumferential extent of less than 360° adhered selectively to at least a portion of the thread defining surface of the fastener. | 1 |
This is a continuation of application Ser. No. 618,278, filed Nov. 26, 1990 now abandoned.
CROSS-REFERENCE TO RELATED APPLICATION
This application relates to U.S. application Ser. No. 07/619,170, filed simultaneously herewith on Nov. 26, 1990, entitled "Machine Tool With Movable Positioning Device" which discloses and claims a machine tool having a positioning device mounted on a carrier which is coupled to the machine tool frame by a static fluid bearing, and to U.S. application Ser. No. 07/619,169 also filed simultaneously herewith entitled "Positioning Device Having a Static Fluid Bearings" which discloses and claims a positioning device for a tool of a machine tool.
BACKGROUND OF THE INVENTION
The invention relates to a support device for a drum which is provided with two journals whose centrelines coincide substantially with the centreline of the drum, which journals project from the drum on either side of the drum and each have their bearing in a bush attached to a frame so that they are rotatable about a common axis of rotation which substantially coincides with the said centrelines.
The wish in many practical situations is for a drum to be able to rotate around its centreline within very narrow tolerance limits. This is the case, for example, when the drum serves to clamp a flexible plate-shaped workpiece which, after being clamped, is machined by means of a feed motion of a tool holder carrying a tool fastened to it in a radial direction relative to the centreline of the drum and by means of a rotational movement of the drum. If the workpiece is clamped around a drum with a high resistance to bending, a rigid cylindrical body is obtained which renders an accurate machining of the workpiece possible. In particular, so-called masters for the manufacture of projection screens in the form of so-called linear Fresnel lenses for projection television are manufactured in this way. In this process, any deviations in the circular movement made by a point on the outer circumference of the drum must remain below one micrometer.
If such a requirement is to be met, it is impossible in general to use ball bearings, as is the case in conventional supports, but it is necessary to use radial fluid bearings which can operate between an outer circumference of a journal and an inner circumference of a bearing bush attached to the frame with small gaps of the order of approximately 12 μm. In addition, the use of radial fluid bearings, in contrast to the conventional ball bearings, makes it possible to accommodate any expansion differences in axial direction between the drum and the frame in a simple way in that the journals can be axially shifted in the bearing bushes.
Now a first problem which arises here, especially in the case of a support device having a relatively long drum, is that the bushes surrounding the journals must be aligned relative to one another with great accuracy so that the centrelines of the said bushes coincide to within a very narrow tolerance and the two journals can be positioned in the bushes with a degree of clearance sufficient for a correct journalling action. In addition, a second problem with such long drums is that the centrelines of the two journals do not coincide. Generally, the axis of rotation about which the drum is rotatable does not coincide with the centreline of the drum in such a case, so that the rotational movement of the drum is inaccurate and the said axis of rotation also fails to coincide with the centrelines of the journals, so that also the rotational movement of the journals relative to the bearing bushes is incorrect, which may lead to an incorrect journalling action.
SUMMARY OF THE INVENTION
The invention has for its object to provide a support device in which the problems mentioned are avoided.
The support device according to the invention is for this purpose characterized in that each of the bushes is attached to the frame by means of a ring-shaped membrane which is situated in a plane transverse to the axis of rotation.
If the ring-shaped membranes are manufactured to a sufficient accuracy, the centreline of each of the two bushes will go through the centre of the relevant membrane and each of the two bushes can be swivelled through relatively small angles relative to the centreline of the relevant membrane about a pivot which coincides with the said centre of the membrane. If an ideally dimensioned drum, in which the centrelines of the journals coincide with the drum centreline, rotates about the axis of rotation in the said support device, each of the two bushes will be swivelled about its pivot in such a way under the influence of the occuring journal forces that its centreline coincides substantially with the centreline of the drum. An automatic alignment of the bushes relative to the drum is obtained in this way.
A particular embodiment of a support device according to the invention which provides a substantially frictionless and very rigid journalling of the drum in a direction parallel to the axis of rotation is characterized in that one of the two journals is journalled in a direction parallel to the axis of rotation by means of an axially operating fluid bearing which comprises a part connected to the frame through an elastic connection which operates as a ball joint, a centre of the elastic connection being situated in the centre of the ring-shaped membrane by means of which the bearing bush surrounding the relevant journal is attached to the frame. It is achieved by the use of the said elastic connection that the part of the axial fluid bearing connected to the frame can swivel about a point which substantially coincides with the pivot formed by the ring-shaped membrane about which the bearing bush, the journal guided therein and the part of the axial fluid bearing attached to the journal can swivel. Thus the entire axial fluid bearing can follow an adjustment movement of the bearing bush, so that a correct operation of the axial fluid bearing remains possible.
A further embodiment of a support device according to the invention, which provides a compact attached of the axial fluid bearing to the frame, is characterized in that the axially operating fluid bearing comprises a tube which projects into the journal, which is attached to an end of a rod attached to the frame and having a centreline substantially coinciding with the axis of rotation, and which surrounds the said rod substantially concentrically, while the rod has a portion of reduced diameter constituting the said elastic connection around the point of intersection of the centreline of the rod and the plane through the ring-shaped membrane. A further object achieved by this is that the axial fluid bearing is situated outside the relevant journal, so that the dimensions of the bearing necessary for a correct bearing operation are not restricted by the small space available inside the relevant journal.
A still further embodiment of a support device according to the invention is characterized in that each of the two journals forms part of a shaft which is attached to the drum by means of a ring-shaped plate situated in a plane transverse to the centreline of the drum, a portion of each shaft which projects into the drum being in engagement with adjustment means by which the relevant shaft can be swivelled relative to the centreline of the drum about a swivelling point which substantially coincides with a point of intersection of the centreline of the drum and the plane through the ring-shaped plate by means of which the relevant shaft is attached to the drum. This achieves that the two shafts with the accompanying journals can be so swivelled about the said swivelling points by the said adjustment means that the centrelines of the shafts coincide. If the ring-shaped plates are manufactured so accurately that the swivelling points lie on the centreline of the drum and the centreline of each of the shafts passes through the swivelling point of the ring-shaped plate attached to the relevant shaft, the centrelines of the two shafts and journals will also coincide with the drum centreline after a correct adjustment. Thus an accurate rotary movement of the drum and of the journals inserted in the bearing bushes is obtained.
A particular embodiment of a support device according to the invention comprising adjustment means by which the shafts can be swivelled in any desired direction relative to the drum centreline in a simple manner is characterized in that an end of the portion of each shaft projecting into the drum is situated with clearance in a support bush attached to the drum and is movable relative to the support bush by means of adjustment bolts screwed into the support bush and bearing on the end of the shaft.
A further embodiment of a support device according to the invention, which provides an effective, accurate, and easily implemented attachment of a shaft to the drum, is characterized in that the drum is composed of drum parts which fit into one another, at least one of the ring-shaped plates by means of which the shafts are attached to the drum being formed by a bottom, or transverse wall, of one of the drum parts. The said composition of the drum from different drum parts moreover leads to a relatively high rigidity of the drum, while the drum length can be adapted to the dimensions of the workpiece to be processed by the addition or removal of one or several drum parts.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be explained in more detail with reference to the drawing in which
FIG. 1 shows a longitudinal section of an embodiment of a support device according to the invention, and
FIG. 2 shows a diagrammatic longitudinal section of this embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The embodiment of the support device shown in FIG. 1 comprises a drum 1 of aluminium built up from a number of cup-shaped drum parts 3 which fit into one another. The drum parts 3 have a stepped profile 5, so that the complete drum 1 with a shell 7 is formed by drum parts 3 fitting together. The centrelines of the cup-shaped drum parts 3 coincide with a centreline 9 of the complete drum 1. Each of the drum parts 3 comprises a bottom 11 in the shape of a ring-shaped plate which is situated in a plane transverse to the centreline 9 of the drum 1. Viewed in relation to a plane transverse to the centreline 9 through the centre of the drum 1, the drum parts 3 situated to the left and to the right of this plane in FIG. 1 are arranged with their bottoms 11 facing away from one another. The bottoms 11 of the two outermost drum parts 3 carry shaft portions 13 and 15 of stepped shafts 17 and 19, fastened by means of diagrammatically indicated screw connections 21 and 23, respectively. As is shown in FIG. 2, the shafts 17 and 19 have respective centrelines 25 and 27. The two screw connections 21 and 23 each comprise a rim of screws applied concentrically around the centrelines 25 and 27, screw holes being present at regular distances from one another in collars 29 and 31 of the stepped shafts 17 and 19. The bottoms 11 of the relevant drum parts 3 are elastically deformable in axial direction, so that the two shafts 17 and 19 can swivel through small angles relative to the centreline 9 of the drum 1 about swivelling points 33 and 35, respectively. The bottoms 11 and the screw connections 21 and 23 are manufactured to such an accuracy that the swivelling points 33 and 35 lie on the centrelines 25 and 27 of the shafts 17 and 19 and coincide with the points of intersection of the centreline 9 of the drum 1 with centre planes through the bottoms 11 of the respective drum parts 3 attached to collars 29 and 31.
The ends of the shafts 17 and 19 situated inside the drum 1, as can be seen in FIG. 1, are surrounded with some clearance and practically concentrically by bushes 41 and 43, respectively, which are attached to the shell 7 of drum 1 by means of rigid ring-shaped plates 45 and 47. Each of the bushes 41 and 43 is provided with screw holes in a plane transverse to the centreline 9 of the drum 1, which holes are regularly spaced viewed in circumferential direction of the bushes 41 and 43 and into which adjustment bolts 49 are screwed whose ends bear on the outer circumference of the end of the shaft 17, 19 surrounded by the relevant bush. The two shafts 17 and 19 can be swivelled about the respective swivelling points 33 and 35 into any desired direction relative to the centreline 9 of the drum 1 by means of the adjustments bolts 49. It is possible in this way to align the shafts 17 and 19 in such a way relative to one another that the two centrelines 25 and 27 of the shafts coincide with the centreline 9 of the drum 1.
After the shafts 17 and 19 have been aligned in the manner described, they can each be locked in the accurately set position obtained by means of screw connections 51 at the bottoms 11 of those drum parts 3 which are situated between the plates 45 and 47, respectively, and the outermost drum parts. The screw connections 51 each comprise a regular rim of screws applied concentrically about the centreline 9 of the drum 1, regularly spaced screw holes being present in collars 53 and 55 of the shafts 17 and 19 close to the points of intersection of each of the centrelines 25 and 27 of the shafts 17, 19 and a centre plane through the bottoms 11 of the drum parts 3 attached to the respective collars 53 and 55. The attachment of the bottoms 11 to the shafts 17 and 19 in the manner described also increases the rigidity of the drum 1, and thus the accuracy of the support device.
As is further shown in FIG. 1, the two shafts 17 and 19 are provided at their ends projecting from the drum 1 with respective steel journals 57 and 59 whose centrelines coincide with the centrelines 25 and 27 of the shafts 17, 19, respectively. The journals 57 and 59 are journalled around an axis of rotation 61 which substantially coincides with centreline 9 in a bearing bush 63 and a bearing bush 65, respectively, each forming part of a radially operating static fluid bearing, which is known per se and is not shown in any detail, for the journals 57 and 59, respectively.
Each of the bearing bushes 63, 65 is attached to a frame 67 of the support device by means of a ring-shaped membrane 69 which is situated in a plane transverse to the axis of rotation 61 and which is rigid in radial direction relative to the axis of rotation 61. The ring-shaped membranes 69, which are elastically deformable in axial direction, as are the bottoms 11 of the outermost drum parts 3, are manufactured to such an accuracy that each of the bearing bushes 63, 65 can swivel through relatively small angles relative to the centreline of the membrane 69 attached to the relevant bearing bush 63, 65 about a pivot 71 which coincides substantially with the centre of the relevant membrane 63 and which is situated on the centreline of the relevant bearing bush. It is achieved in this way that the two bearing bushes 63, 65 can be so swivelled under the influence of forces exerted by the two radial static fluid bearings that the centreline of each bearing bush 63, 65 in all circumstances substantially coincides with the centreline 25, 27 of the journal 57, 59 supported by the relevant bearing bush 63, 65. Under the influence of the said bearing forces, the two bearing bushes 63 and 65 are self-adjusting, so that a clearance necessary for a correct bearing operation is always present between the journals 57, 59 and the bearing bushes 63, 65. If the shafts 17 and 19 are ideally aligned, the centrelines 25 and 27 of the shafts 17, 19 coinciding with the centreline 9 of the drum 1, the axis of rotation 61 substantially coincides with the said centrelines 9, 25 and 27, and an exact rotational movement of the drum is obtained. If the centrelines 25 and 27 of the shafts 17, 19 do not exactly coincide with the centreline 9 of the drum 1, the axis of rotation 61 generally passes through the two pivots 71 of the membranes 69, and there is an eccentricity of the centreline 9 relative to the axis of rotation 61. This situation is shown in an exaggerated form in FIG. 2. Since the centreline 9 and the two centrelines 25 and 27 do not coincide with the axis of rotation 61 now, the rotational movement of the drum 1 and of the journals 57 and 59 is slightly inaccurate. Thanks to the swivelling suspension of the two bearing bushes 63 and 65, these bearing bushes 63, 65 are capable of following the inaccurate rotational movement of the journals 57, 59, so that a correct bearing operation remains possible.
The drum 1 is journalled in a direction parallel to the axis of rotation 61 by means of an axially operating static fluid bearing 75 pre-tensioned by permanent magnets 73 of a type which is known per se and which is not shown in FIG. 1. The static fluid bearing 75 is situated near an end of the journal 57 and comprises, as is shown in FIG. 1, a ring-shaped part 77, which is attached to journal 57 concentrically around centreline 25, and a ring-shaped part 79, which is also positioned concentrically around centreline 25 and is attached to the frame 67. A tube 81 is attached to the ring-shaped part 79 of the axial fluid bearing 75 and projects into the journal 57, while it is connected to a rod 83 attached to the frame 67 near its end. The centreline of rod 83 coincides substantially with the axis of rotation 61, while the tube 81 surrounds the rod 83 substantially concentrically. The rod 83 comprises a portion of reduced diameter 85 which is situated around a point of intersection of the centerline of the rod 83 and the plane through the ring-shaped membrane 69 by which the bearing bush 63 of journal 57 is attached to the frame 67. The portion of reduced diameter 85 forms an elastically deformable connection between the axially operating static fluid bearing 75 and the frame 67, acting as a ball joint, so that the ring-shaped part 79 of the fluid bearing 75 together with the tube 81 can swivel through small angles about a point which lies in the centre of the portion of reduced diameter 85 and coincides substantially with the centre of the ring-shaped membrane 69. It is achieved in this way that the two ring-shaped parts 77 and 79 of the fluid bearing 75 can swivel about the same point, so that the entire fluid bearing 75 can follow an adjustment movement of the bearing bush 63 and a correct operation of the fluid bearing 75 thus remains possible.
It should be noted that the use of a fastening construction of the axial static fluid bearing 75 to the frame 67 as described above means that the fluid bearing 75 is mounted outside the journal 57. In principle, the fluid bearing 75 may also be mounted inside the journal 57 by means of a construction which is in itself simpler, and may, for example, be attached to the journal 57 at the flat wall 87 of the journal 57. Whether such a simpler construction is possible depends on the available space inside the journal 57. The size of this space is determined by, among other factors, the necessary bearing force of the radial and axial fluid bearings.
It should further be noted that the term ring-shaped membranes 69 is understood to refer to thin, ring-shaped plates which are so rigid in a radial direction relative to the axis of rotation 61 and which have such an elastic deformability in an axial direction relative to the axis of rotation 61 that the swivelling movement of the bearing bushes 63, 65 referred to above is possible. Instead of the ring-shaped membranes 69 used here, with which the bearing bushes 63, 65 are attached to the frame 67, or instead of the ring-shaped plates 11 of the outermost drum parts 3 used here, with which the shafts 17, 19 are attached to the drum 1, other fastening means may alternatively be used, which means may be built up from, for example, spoke-shaped parts provided in radial direction in a plane transverse to the axis of rotation 61 and elastically deformable in a direction perpendicular to this plane, or from thin, ring-shaped plates provided with windows.
As was mentioned above, an inaccurate rotary movement of the journals 57 and 59 caused by imperfect coincidence of the centrelines 25 and 27 of the shafts 17, 19 can be followed by the bearing bushes 63 and 65. The degree to which this is possible is determined by, among other factors, the dimensions of the two membranes 69. The adjustment means by which the shafts 17 and 19 can be swivelled relative to the centreline 9 of the drum 1 are accordingly unnecessary in principle, provided sufficiently large membranes 69 can be used, which is sometimes impossible or impracticable in view of the admissible dimensions of the support device, or in the case in which the centrelines 25, 27 of the shafts 17, 19 are capable of coinciding to within very narrow tolerances without adjustment means, which is difficult to achieve if the dimensions of the drum 1 are large.
It should also be noted that, instead of the static fluid bearings, dynamic fluid bearings may alternatively be used, which bearings are provided with known means for enabling starting and stopping of a rotational movement of the drum 1 without damage to bearing surfaces.
Finally, it is noted that each of the ring-shaped plates 45, 47 with which the bushes 41, 43 are attached to the drum 1 may also be formed by a bottom 11 of one of the drum parts 3. | A support device for a drum (1) which is provided with two journals (57, 59) projecting from the drum on either side of the drum, whose centerlines (25, 27) substantially coincide with the centerline (9) of the drum. Each of the two journals (57, 59) is journalled around an axis of rotation (61) in a bearing bush (63, 65) which is attached to a frame (67) by a ring-shaped membrane (69) positioned in a plane transverse to the axis of rotation (61). Each of the two journals (57, 59) forms part of a shaft (17, 19) projecting into the drum (1), and attached to a shell (7) of the drum by a ring-shaped plate (11). An end of a portion of each shaft (17, 19) projecting into the drum (1) bears on adjustment devices (41, 43, 49) by which the relevant shaft (17, 19) with journal (57, 59) can be swivelled relative to the centerline (9) of the drum (1). In particular, such a support device is used for a drum (1) which serves as a rotating carrier for a plate-shaped workpiece which is to be machined accurately by a cutting tool, such as, for example, a master for the production of projection television screens. | 5 |
BACKGROUND OF THE INVENTION
[0001] I. Field of the Invention
[0002] This invention relates generally to a height adjustable pillow and, more specifically, to a pillow having an extendable and resilient pillow body, inside which installed an air cushion that can be charged or discharged. By adjusting the amount of air filled in the air cushion, the thickness of the pillow can be manipulated.
[0003] II. Description of the Prior Art
[0004] For a good night's sleep, a soft and fluffy pillow with flexibility is provided with build in head and neck support. A pillow of such construction is typically made of soft plastic, soft rubber, or foam products of plastic and rubber. It is also known to construct a pillow ergonomically designed to have a curved contour, with one higher hump and one lower hump. A pillow of this kind is typically made of special foams to provide pressure relief and is called “memory form”.
[0005] Such kind of pillow typically has limited sizes available, which means the shape and thickness can't be freely modified to fulfill different sleep needs. To manufacturers, providing multiple sizes of pillows is not economical since it inevitably increases cost for production and still may not suit all consumers' need. Although some adjustable pillows are available on the market, they are not well-design to meet the needs of consumers.
[0006] The present invention improves on the heretofore known pillow by providing an adjustable air cushion inside the pillow so that users can freely modify the thickness to suit their special needs.
SUMMARY OF THE INVENTION
[0007] It is therefore a primary object of the present invention to provide a height adjustable pillow having a pillow body and an air cushion. The pillow body is extendable and resilient, made of soft plastic, rubber, or foam products of plastic and rubber. Inside the pillow body is a chamber for accommodating the air cushion. By charging or discharging air through a valve, the thickness of the pillow can be easily modified.
[0008] Another object of the present invention is to provide a height adjustable pillow, of which the air cushion can be freely charged and discharged so that users can modify the thickness of the pillow to create sleep comfort.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, in which:
[0010] FIG. 1 is an explosive view of an embodiment in accordance with the present invention;
[0011] FIG. 2 is a perspective view of an embodiment shown in FIG. 1 while being adjusted height;
[0012] FIG. 3 is a schematic drawing of the cross sectional view of an embodiment in FIG. 1 ;
[0013] FIG. 4 is a view similar to FIG. 3 in which the air cushion is being charged;
[0014] FIG. 5 is a sectional view of an air cushion of the present invention;
[0015] FIG. 6 is a schematic drawing of an embodiment in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0016] Referring to FIG. 1 and FIG. 2 , the present invention discloses a height adjustable pillow 1 , comprising a pillow body 10 and an air cushion 20 . The pillow body 10 is made of soft plastic, rubber or foam products of plastic and rubber and thus is extendable and resilient, always resuming its original shape after being squeezed or pulled. The pillow body 10 can be of any shape. For example, the pillow body 10 can have an ergonomically-designed, curved contour with a higher hump 12 in the front and a lower hump 13 in the rear of the surface 11 , as shown in FIG. 5 . The pillow body 10 can be covered by a pillow case 30 . Moreover, inside the pillow body 10 , there is a flat and thin chamber 14 which is produced in different ways. For example, the chamber 14 may form its shape during the foaming process of the pillow body 10 . The horizontal area of the chamber 14 is expected to cover most of the area of the surface 11 , as shown in FIG. 3 . A ceiling 15 of the chamber 14 is expected to keep an adequate distance from the surface 11 to ensure that the pillow body 10 provides soft and firm support.
[0017] The air cushion 20 is designed to fit the shape and size of the chamber 14 so that the air cushion 20 can be put into the chamber 14 and fill the space in the chamber 14 when the air cushion 20 is fully charged with air. There are two ways of fitting the air cushion 20 in the chamber 14 . First, the chamber 14 is thin and flat, with only one lining (not shown in the figures). As the air cushion 20 is discharged, the air cushion 20 is almost flat and will not affect the height of the pillow body 10 or the surface 11 when it is inserted to the chamber 14 . Since the space in the chamber 14 is small, and the pillow body 10 is firm and resilient, the pillow body 10 does not depend on the air in the air cushion 20 for support, and so the surface 11 is able to maintain its normal altitude as the air cushion 20 is discharged. Second, the chamber 14 is large enough to leave a relatively empty space, as can be seen in FIG. 1 , FIG. 2 and FIG. 3 . As the air cushion 20 in the chamber 14 is discharged, the air cushion 20 is flat, and the surface 11 is at a relatively lower altitude. The air cushion 20 has to be charged to fill the space in the chamber 14 . With air filling the space in the chamber 14 , the surface 11 goes up and resumes its normal altitude.
[0018] Refer to FIG. 3 , FIG. 4 and FIG. 5 , the top layer 21 of the air cushion 20 serves as a supporting plane that moves vertically to support the ceiling 15 of the chamber 14 . The inner space of the air cushion 20 is evenly segmented into a plurality of air cells 22 that are connected with each other and of the same size. While being charged or discharged, the air cells 22 of the air cushion 20 expand or shrink evenly so that the entire top layer 21 maintain at the same altitude to support the ceiling 15 of the chamber 14 and make the surface 11 go up and down. The valve 23 of the air cushion 20 is positioned at an opening of the chamber 14 in the pillow body 10 .
[0019] To adjust the altitude of the surface 11 of the pillow 1 , users can apply any kind of air pump 2 , as shown in FIG. 2 , to charge or discharge the air cushion 20 (the air pump 2 can be included in the product package, going with the pillow 1 ). With evenly expanding or shrinking of the air cushion 20 , the altitude of the top layer 21 changes. As achieving the optimal altitude of the surface 11 , users close the valve 23 , as shown in FIG. 6 , and then enjoy the best degree of comfort.
[0020] While a preferred embodiment of the invention has been shown and described in detail, it will be readily understood and appreciated that numerous omissions, changes and additions may be made without departing from the spirit and scope of the invention. | A height adjustable pillow includes an extendable and resilient pillow body and an air cushion installed in a chamber inside the pillow body. The pillow body is made of soft plastic, rubber or foam products of plastic and rubber. The air cushion can be charged or discharged to adjust the thickness of the pillow, providing comfort with firm support and enhancing sleep quality. | 0 |
TECHNICAL FIELD
The invention relates to a warp knitting machine, especially a crochet galloon machine, having knitting needles which are guided on a knock-over bar and which include warp guide bars having warp guides and weft guide bars having and weft guides.
PRIOR ART
A warp knitting machine of the type mentioned in the introduction is known, for example, from DE-A-27 58 421. In this warp knitting machine, the weft guide bars and the weft guides arranged thereon must be moved not only to and fro along the weft guide bars, but also up and down, in order to underlay a corresponding weft yarn on a knitting needle. In this case, the weft guide bars are exposed to a very high dynamic load, thus resulting in sagging, wear and high noise emission. In order to counteract this, the bars must have a very large cross-section and therefore require a large amount of space. This space requirement, on the one hand, and the only limited free space available on the warp knitting machine, considerably restrict the maximum number of weft guide bars, for example to eight. An improvement to a maximum of sixteen can be achieved by improving the design according to WO 94/23 106. In this case, two weft guide bars are designed so as to be one above the other and so as to engage one into the other. In this design too, there are still the disadvantages that the weft guide bars have to be moved not only to and fro but also up and down, so that high inertia forces, strong vibrations, high noise emission and wear occur. The maximum speed of such warp knitting machines is therefore restricted, for example to 1200 revolutions/minute. In addition, in view of the fact that an ever smaller needle gauge of four to ten needles per cm is demanded nowadays, the knitting needles have very thin cross-sections, with the result that the needles are highly susceptible to flexions and oscillations. At the present time, it is customary to restrict the maximum free knitting needle length to approximately 50 times the needle thickness in the gauge direction. The warp yarns are inserted into the knitting needle heads when the needles are in the extended position. The distance between the knock-over bar and this extended position is available for the number of racking rows for weft guidance and, at the present time, amounts to a maximum of seven rows. Yarn guides having tips or having small end tubes serve for laying the weft yarns under and between the knitting needles. Furthermore, the tip of the yarn guide may also be provided with a small end tube which, however, takes up a relatively large amount of space. The racking gauge is therefore nowadays, on average, approximately 3 mm. This restricts the number of racking levels to seven, on the assumption of a knitting needle stroke of 25 to 30 mm. Also because up to seven yarn guide tips, which have to engage into a knitting needle gap between the knitting needles, cannot be oriented exactly in one line, there is contact with the knitting needles, and these begin to vibrate or may be damaged, thus impeding insertion of the warp yarns in the knitting needle heads and greatly restricting the rotational speed of warp knitting machines.
Since, on the one hand, the yarn guides for laying the weft yarns under the knitting needles have to penetrate into the knitting needle gaps and since, on the other hand, the guidance of weft yarns over long distances is driven via a crank mechanism, a certain number of knitting needles must be omitted at the reversal point of the yarn guide. This affords the disadvantage that the useful knitting length is reduced or that weft guidance must be driven via cam mechanisms, thus, in turn, restricting the maximum rotation speed of warp knitting machines.
According to the prior art, the knitting point is designed on the crochet galloon principle, as a result of which it is not possible for the yarns to be beaten up on the selvedge. This affords the disadvantage that it has hitherto been possible to produce only knitted fabrics having a relatively low weft density. The area of use of warp knitting machines is thereby restricted.
SUMMARY OF THE INVENTION
The object of the invention is to improve a warp knitting machine of the type mentioned in the introduction.
The set object is achieved by means of the provision of weft guides which do not cross through the knitting needles and the assignment of feeders to the weft guides, which feeders are guided and can be driven up and down between the weft guides and the knitting needles transversely to the racking direction of the weft guide bars. This enables the feeders to lay racked weft yarns under the associated knitting needles
Since the weft guides of the weft guide bars do not intersect the knitting needles, they also do not have to be moved up and down, a to-and-fro movement instead being sufficient. The weft yarns are supplied to the knitting needles by the feeders. This results in an appreciable simplification of the weft guide and of the weft guide bars, so that a very large, hitherto impractical number of weft guide bars and weft guides is possible. The number of racking rows is also no longer necessarily restricted, so that the maximum possible number is equal to the number of installed weft guide bars. Furthermore, the knitting needle stroke can be reduced to a minimum size, since there need only be space for a single feeder in a knitting needle gap between the knitting needles. The knitting needle stroke is therefore essentially dependent on the width of the feeder. Since the weft guides no longer enter the knitting needle gaps between the knitting needles, operation is possible with weft guidance of virtually any length, without any loss of knitting needles. This may be further assisted by using electronically controlled drives for driving the weft guide bars, the said drives allowing smooth motion so as to treat the weft yarns carefully.
Advantageous embodiments of the invention are further described herein.
It is possible in principle for the weft guide bars to execute not only a to-and-fro movement, but also a movement transverse to this, provided, however, that the weft guides do not intersect the knitting needles. It is more advantageous, however, if the weft guide bars and therefore also the weft guides execute only a to-and-fro movement in their longitudinal direction, thereby appreciably simplifying the drive and mounting, so that a larger number of weft guide bars and consequently weft guides may be used. It is also advantageous if the knitting needles execute only a to-and-fro movement along their knitting axis.
It is possible in principle for not every knitting needle to be assigned a feeder, but the embodiment wherein each knitting needle is assigned a feeder is more advantageous.
It is conceivable that the feeders do not cross through the weft guides of the weft guide bars and the knitting needles, but run at a distance from these. However, an embodiment wherein the feeders cross through the weft guides of the weft guide bars and the knitting needles in a finger-like manner is especially advantageous, the result of this being that not only is a more compact design achieved, but the operating capacity of the warp knitting machine is also increased.
The feeders may, if appropriate, be driven individually or in groups, but an embodiment wherein the feeders are arranged on a common, drivable on a common feeder bar is more advantageous.
The feeders may be movable along a straight path and/or along arcuate paths. Especially advantageous is a design wherein the return travel of the feeder from the knitting point is arranged at a distance from the weft guides, which makes it possible for the return travel of the feeders to lie outside the weft guides, so that racking of the weft guide bars can take place as early as during the return travel of the feeders.
As regards the arrangement of the weft guide bars together with the weft guides, various possibilities arise, such as, for example, wherein the weft guide bars together with the weft guides are arranged in such a way that the weft yarns are supplied to the knitting point by the weft guides essentially in the same direction as the warp yarns, or where the weft guides are arranged in such a way that the weft yarns are supplied to the knitting point by the weft guides in the opposite direction to the warp yarns.
An advantageous arrangement of the weft guide bars is provided where they are arranged in such a way that the mouths of the weft guides are arranged along a straight or arcuate surface relative to the knitting point.
Various possibilities arise for the design of the feeders such as the provision of a downwardly open fork-shaped head on the feeders for grasping the weft yarns. The development wherein the feeders have guide elevations on each of the two sides on a head engaging into the knitting needle gap between the knitting needles improves the stability and operating reliability of the feeders. A development wherein the feeders are designed in such a way that they press or beat up the weft yarns onto the selvedge of the knitted fabric after crossing through the knitting needles is also especially advantageous, the result of this being that a close-packed knitted fabric can be produced.
Various possibilities arise as regards the drive of the weft guide bar and/or of the warp guide bar. The possibility wherein the weft guide bars can each be driven by means of an electrical actuator which can preferably be controlled by means of an electronic control device is especially preferred, since an electronically controlled actuator constitutes, for each guide bar, an effective drive which takes up little space and can be controlled in a simple way, both as regards the timing and as regards the stroke size, according to a predeterminable pattern for producing the knitted fabric.
The embodiment wherein the magnitude of the up-and-down movement of the feeders is adjustable is also especially advantageous, according to this the magnitude of the up-and-down movement of the feeders being adjustable.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the invention are described in more detail below with reference to the diagrammatic drawings in which:
FIG. 1 shows a vertical section through a first warp knitting machine, with the feeder raised;
FIG. 2 shows, as a detail, the warp knitting machine of FIG. 1, with the feeder in the initial position, in a view towards the weft guide bars;
FIG. 3 shows, as a detail and on a larger scale, the warp knitting machine of FIG. 2, with the feeder at the knitting point, in a view towards the weft guide bars;
FIG. 4 shows a vertical section through a further warp knitting machine, with the feeder in the initial position;
FIG. 5 shows, as a detail and on a larger scale, the warp knitting machine of FIG. 4, with the feeder at the knitting point;
FIG. 6 shows a plan view of the warp knitting machine of FIG. 5;
FIG. 7 shows the warp knitting machine of FIG. 4, with the feeder on its return travel; and
FIG. 8 shows a vertical section through a further warp knitting machine, with the weft guide bar arranged along an arcuate surface.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 to 3 show a first exemplary embodiment of a warp knitting machine which has knitting needles 34 which are guided and driven back and forth in their longitudinal direction in a knock-over bar 32 and which are preceded by warp guides 36 . The warp guides 36 are fastened to a warp guide bar 38 and execute a movement about the knitting needles 34 , in order, in each case, to insert a warp yarn 40 into a knitting needle 34 when the latter is in the foremost position, as indicated by broken lines in FIG. 1 . In this exemplary embodiment, the knitting needles 34 are designed as spring-hook needles and are driven in a known way not illustrated in any more detail.
A stack of weft guide bars 44 bearing the numbers 1 to 24 is arranged above the knitting needles 34 on a carrier 42 and is held on the topside by a guide 46 . Each weft guide bar 44 contains a row of weft guides 48 in the form of small tubes, in order to supply weft yarns 50 to the knitting point 52 . For the mutual guidance of the weft guide bars 44 , there are, for example, grooves 54 , into which tongues 56 of the adjacent components engage. As emerges especially from FIGS. 3 and 4, the individual weft guide bars 44 are individually driven to and fro, solely in the longitudinal direction, by means of individual actuators 58 , for example electrically driven linear motors, via corresponding gears 60 . These actuators 58 are connected to an electronic computer-assisted control device 61 which controls the use and/or stroke of the actuators 58 according to the particular pattern.
For supplying the individual weft yarns 50 to the knitting point 52 , there are feeders 62 arranged on a feeder bar 64 which can be moved, in a way not illustrated in any more detail, up and down out of the initial position A represented by broken lines into the knitting position W represented by unbroken lines. The feeders have a fork-like head 66 and, after the weft guides 48 have been racked, pass through the latter in a finger-like manner, in order to carry the respectively racked weft yarns to the knitting point 52 and lay them under the knitting needles 34 , before the latter are moved out of the retracted position into the advanced position (represented by broken lines in FIG. 1 ). During the feed, the feeders 62 move right up to the selvedge 68 , with the result that it is possible to produce a very close-packed knitted fabric 70 which is drawn off from the knitting point 52 by a draw-off device 72 .
By means of the weft guide bars 44 bearing the numbers 1 to 24 and their weft guides 48 , it is possible to use weft yarns 50 of the most diverse types, such as, for example, having different thickness, twisting, materials (such as rubber yarns), but also different make-up, for example as regards colour, shading and fleeciness. At the same time, such weft yarns may, for example, be laid as a stem S in only one warp K or as a part weft over some of the width or as a long weft LS over the entire width of the knitted fabric 70 .
FIGS. 4 to 7 illustrate a further exemplary embodiment of a warp knitting machine which corresponds essentially to that of FIGS. 1 to 3 , so that identical parts are given the same reference symbols, but with the addition of the index a.
In contrast to the warp knitting machine of FIGS. 1 to 3 , that in FIGS. 4 to 7 is modified particularly to the effect that the weft guide bars 44 a together with the weft guides 48 a are arranged in such a way that the weft yarns 50 a are supplied to the knitting point 52 a by the weft guides 48 a essentially in the same direction as the direction of the warp yarns 40 a supplied by the warp guides 36 a . The feeders 62 a on the feeder bar 64 a are arranged on a rotating drive device 74 , not illustrated in detail, in such a way that they are moved downwards out of the initial position A illustrated in FIG. 4, at the same time combing through the weft guides 48 a in a finger-like manner, into the knitting position W at the knitting point 52 a , as illustrated especially in FIGS. 5 and 6. In this position, they lay the carried-along weft yarns 50 a behind the knitting needles 34 a which, in the present example, are designed as compound needles. To guide the feeders 62 a back out of the knitting position, they are moved forwards out of the region of the weft guides 48 a by means of the drive device 74 and pass, free of the weft guides 48 a , into the initial position A by way of the return travel 75 . As early as during this return movement, the weft guide bars 44 a can be racked again according to the particular pattern, so that the performance of the warp knitting machine can be improved thereby.
As emerges especially from FIGS. 5 and 6, the feeders 62 a have, once again, a fork-shaped head 66 a which is provided with guide elevations 78 on the part penetrating into the knitting needle gap 76 between the knitting needles 34 a , in order, on the one hand, to make it easier for the feeders 62 a to penetrate into the knitting needle gaps 76 and, on the other hand, to keep the knitting needles 34 a at a distance from one another.
The warp knitting machine of FIGS. 4 to 7 is, further, modified to the effect that the weft guide in bars 44 a and consequently also the weft guides 48 a , together with the carrier 42 a and guide 46 a , are arranged at an inclination to the horizontal such that the weft yarns 50 a make it possible to have as unimpeded a run-through to the knitting point 52 a as possible. Moreover, the knock-over bar 32 a is assigned a panel holder 80 which forms with the knock-over bar a guide clearance 82 of the knitted fabric 70 a which is drawn off by the draw-off device 72 a.
FIG. 8 shows a further warp knitting machine which corresponds in functional terms to the above warp knitting machines of FIGS. 1 to 7 , so that identical parts are given the same reference symbols, but with the addition of the index b.
The knitting needles 34 b arranged in the knock-over bar 32 b are preferably designed as spring-hook needles. The knock-over bar 32 b is assigned a panel holder 80 b which forms with the latter a guide clearance 82 b . The knitting needles 34 b are preceded by warp guides 36 b , arranged on a warp guide bar 38 b , for the supply of warp yarns 40 b.
The weft guide bars 44 b together with the weft guides 48 b are arranged above the knitting needles 34 b , specifically opposite to the direction in which the warp yarns 40 b are supplied to the knitting point 52 b . Moreover, the arrangement of the weft guide bars 44 b and of the weft guides 48 b is such that they lie along an arcuate path 86 , along which the feeders 62 b arranged on a feeder bar 64 b also travel through the yarn guides 48 b in a finger-like manner from the initial position A into the knitting position W.
The drive device 74 b for the feeder bar 64 b and for the feeders 62 b is designed in such a way that the return travel 75 b for the fork-shaped head 66 b of the feeders 62 b lies outside the weft guides 48 b . For this purpose, the feeder bar 64 b is fastened to a rocker lever 88 which rocks about the axis 90 which itself describes the eccentric travel 94 by means of a driven eccentric 92 , with the result that the distance between the arcuate supply path 86 and the return travel 75 b remote from this is determined by the weft guides 48 b . The up-and-down movement is generated by an eccentric drive 96 , the eccentric 98 of which is connected to a connecting rod 100 , the other end of which is coupled to the rocker lever 88 via a joint 102 .
LIST OF REFERENCE SYMBOLS
A Initial position 60 Gear
LS Long weft 61 Control device
K Warp 62 Feeder
S Stem 62 a Feeder
W Knitting position 62 b Feeder
32 Knock-over bar 64 Feeder bar
32 a Knock-over bar 64 a Feeder bar
2 b Knock-over bar 64 b Feeder bar
34 Knitting needle 66 Head, fork-shaped
34 a Knitting needle 66 a Head, fork-shaped
34 b Knitting needle 66 b Head, fork-shaped
36 Warp guide 68 Selvedge
36 a Warp guide 68 a Selvedge
36 b Warp guide 70 Knitted fabric
38 Warp guide bar 70 a Knitted fabric
38 a Warp guide bar 70 b Knitted fabric
38 b Warp guide bar 72 Draw-off device
40 Warp yarn 72 a Draw-off device
40 a Warp yarn 74 Drive device
40 b Warp yarn 74 b Drive device
42 Carrier 75 Return travel
42 a Carrier 75 b Return travel
44 Weft guide bar 76 Knitting needle gap
44 a Weft guide bar 78 Guide elevation
44 b Weft guide bar 80 Panel holder
46 Guide 80 b Panel holder
46 a Guide 82 Guide clearance
48 Weft guide 82 b Guide clearance
48 a Weft guide 86 Path, arcuate
48 b Weft guide 88 Rocker lever
50 Weft yarn 90 Axis
50 a Weft yarn 92 Eccentric
50 b Weft yarn 94 Eccentric travel
52 Knitting point 96 Eccentric drive
52 a Knitting point 98 Eccentric
52 b Knitting point 100 Connecting rod
54 Groove 102 Joint
56 Tongue
58 Actuator | The invention relates to a warp knitting machine, especially a crocheting machine, comprising knitting needles guided on a knock-over sinker with warp thread layers which are fitted upstream with warp thread guides and weft thread layer rods assigned to weft thread guides. The invention provides an improvement to a warp knitting machine, characterized in that the weft thread guides of the weft thread layer rods do not cross the knitting needles and the weft thread guides of the weft thread layer rods are assigned feeding means relative to the knitting needles, which can be guided and driven upwards and downwards between the weft thread guides and the knitting needles in such a way that the feeding means place staggered weft threads underneath the assigned knitting needles. | 3 |
FIELD OF THE INVENTION
This invention relates to a design for and a method of making a magnetic head slider assembly of the type that rides on an air bearing.
BACKGROUND OF THE INVENTION
Since the first movable head disc file was manufactured in quantity in the late 1950s, air lubricated slider bearings have been used to house and position the magnetic transducer over a spinning disc for data recording. The film of air that moves with the spinning disc serves to support the head at a predetermined fixed distance above the disc surface. A desired characteristic of a slider bearing used to support such a head is that only small variations in flying height result as the slider is accessed to different radial locations over the disc surface. As the flying height varies, different magnitudes of write current may become necessary to obtain an essentially constant signal amplitude in the recorded data. If the head to disc spacing is maintained nearly constant, compensation of the write current is not necessary. However, the relative speed between the head and the recording surface varies as the head is moved radially across the disc surface, since for any selected revolutions per minute, those surface portions located at greater radii from the center are moving much faster than those nearer the center. Thus, the film of air on which the head rides also varies in speed and possibly in thickness.
In recent years the trend has been towards reducing the flying height of the head. Such is necessary to increase the recording density of the data. Naturally, the reduction in spacing between the head and recording surface increases the chances for head crashes thereby requiring more precision in the control of the flying height of the head. To compensate for the lower flying height, therefore, stiffer air bearings have been designed to provide improved stability. Concurrent with this trend has been the use of smaller low mass sliders that start and stop in contact with the disc surface. This requires that only a small load force be applied to the slider in order to minimize wear to the magnetic surface of the disc.
One of the more current slider bearing design concepts involves two rails separated by a relieved section capable of dynamically generating a partial vacuum, thereby eliminating or reducing the need of an external loading force. An example of such an assembly is shown in U.S. Pat. No. 3,855,625 entitled Magnetic Head Slider Assembly issued on Dec. 17, 1974 with Garnier et al as inventors. Such a slider bearing is composed of two rails separated by a relieved section with each rail having a taper flat configuration. The taper flat serves to pressurize the lubricant i.e. air, and the slider is supported by the distributed load carried by the thin air film. The relieved section produces a vacuum suction force which counter-balances the load caused by the taper flat configuration of the two rails. The slider is mounted on a gimbaled flexure suspension, which provides multiple degrees of freedom for excursion of the assembly. Typically, the magnetic transducer is mounted at the trailing edge of one slider rail.
The type of slider disclosed in this patent is generally known as a "zero load" slider. The "zero load" slider exhibits the characteristics of both a low static load and a high air bearing stiffness rendering distinct advantages in maintaining a constant spacing with the disc surface while presenting low contact forces when resting on the disc surface. However, the "zero load" slider by virtue of its relieved section for producing vacuum suction forces, does require extra fabrication processes such as etching and the materials necessary for manufacture of the slider assembly have made control of these processes difficult. Thus, because of rejection rates and other reasons, such a slider assembly has been made more expensive.
It is the purpose of the present invention to provide an improved design and method for manufacturing a "zero load" slider of the type discussed above.
SUMMARY OF THE INVENTION
A device and the method of manufacture therefore, comprising a slider having a surface for flying along a recording surface on which data is recorded. The slider includes an air bearing region extending generally parallel to the recording surface to create a positive pressure region tending to support the slider and a negative pressure region for creating a negative pressure tending to hold said slider close to the recording surface. Positioned between the air bearing region and the negative pressure region is a narrow buffer pad of air bearing surface. One edge of this pad borders on the negative pressure region. The other edge of the pad is separated from the main air bearing surface by a groove or channel of reasonable depth.
DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a prior art slider for supporting a transducer above a recording medium surface.
FIG. 2 is a perspective view of a slider incorporating the present invention.
FIG. 3 is a bottom view in smaller detail of the slider shown in FIG. 2.
FIG. 4 is a cross sectional view along the line 4--4 of FIG. 3.
FIG. 5 is a second embodiment of the present invention.
DESCRIPTION OF THE INVENTION
In FIG. 1 is shown a prior art slider assembly 10 comprising two side rails 12 and 14 and a cross rail 16 joining the two spaced paralled side rails.
As the slider assembly is positioned with the rail surfaces 12A and 14A adjacent a recording surface (not shown), a positive pressure region is created between these rail surfaces and the recording surface. The fluid or air being pulled along with the recording medium surface, which ordinarily is a rotating disc, is compressed by the forward taper surfaces 17 and 18 and serves as a lubricant and cushion on which the slider assembly is supported. Fixed to the trailing edges of the rails are transducers 19 and 20, which extend flush with the rail surfaces 12A and 14A respectively. These transducers serve to interact with the magnetic coating on the recording medium to record and read back information on the medium.
For causing close tracking of the slider assembly along the recording surface, there is formed the recessed area 21 bordered by the side rails 12 and 14 and the cross rail 16, which area creates a sub-ambient pressure region. This negative pressure region causes a suction force between the slider assembly and the recording medium surface serving to attract the slider to the surface. Thus, the air bearing or higher pressure region adjacent the surfaces 12A and 14A of the side rails serves to support the slider assembly while the lower pressure region attracts it towards the medium surface. The height that the slider assembly rides above the medium surface is that height at which these forces are equalized.
Since the rails present air bearing surfaces which can be closely controlled in area, the positive pressure region is controlled thereby closely regulating the magnitude of the supporting force. The suction force between the slider assembly and the recording surface depends upon the volume of expansion of the air passing beneath the cross bar 16 and into the low pressure region. Naturally, a change in the volume of the low pressure region 21, results in a change in the negative pressures and the suction force between the slider assembly and the recording surface.
Normally, the recessed zone has a depth on the order of ten microns. Such a zone is difficult to fabricate with accuracy. One preferred method of fabrication has involved etching the material away in the recessed zone, but the etching process is somewhat difficult to control and the problem is compounded in prior art sliders because underetching has frequently resulted in increasing the size of the air bearing surface, thereby compounding the overall effect on the slider operation. In the same manner, overetching of the low pressure zone has reduced the air bearing surface to compound the problem. Furthermore, some materials are more difficult to etch than others and frequently those that can be etched accurately to meet the tolerances necessary fail to meet other requirements for the slider, such as providing the wear quality required.
In accordance with the present invention, there is formed at the adjacent sides of the pads 12 and 14 relatively deep grooves 25 and 26 respectively by such conventional means as grinding. Narrow air bearing buffer pads 27 and 28 are thereby formed between the grooves and the recessed zone 21 such that the recessed zone is no longer bounded by the side rails 12 and 14. By incorporating this structure, the air bearing surfaces 12A and 14A are closely controlled in size since the boundaries thereof are determined by conventional machining methods. Formation of the recessed area 21 no longer affects the area of the side rails. While it is true that the width of the buffer pads 27 and 28 may vary, it has been found that these pads are sufficiently narrow to present little or no air bearing effect because the fluid spills to either side of the pads and does not form a significant positive pressure region on the pad surface. Such spilling is encouraged by the low pressure region adjacent the surface 21 and the ambient pressure region within the channels 25 and 26. Thus, there is provided a slider having precision measurements to allow close controlling of the operating parameters.
In FIG. 5 is shown yet another design of the subject invention, wherein each of the components remain substantially the same, with the exception of the cross rail 16A. Cross rail 16A is V shaped preferably to be made by etching with the apex 16B pointing in the same direction as the taper pads 17 and 18 so as to cause an air flow in the direction of the arrows 30, extending along the face of the cross rail and then through the channels 25 and 26. Of course some air will flow beneath the cross rail as in the previous embodiment. In this manner, most dirt particles, etc., can be caused to flow down the channels and past the slider rather than becoming lodged on the cross rail face. | A slider for flying along a recording surface and carrying a recording head (19,20) for recording data, comprising an air bearing region (12,14) to create a positive pressure region tending to support the slider, and a negative pressure region (21) tending to hold the slider close to the recording surface, with buffer pads (27,28) and grooves (25,26) between the positive and negative pressure regions to create a neutral pressure zone separation. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
[0002] Not applicable.
BACKGROUND OF THE INVENTION
[0003] Pipetting devices are in particular used in the laboratory for metering liquids. They are drawn into pipette tips through a tip orifice and dispensed. With air cushion pipettes a displacement device for a gas is incorporated in the pipetting device and communicatingly connected to the pipette tip by the attachment. An air cushion is displaced by means of the displacement device, so that liquid is suctioned into the pipette tip and ejected therefrom. The displacement device is generally a cylinder with a piston which can be displaced therein.
[0004] The pipette tips are releasably connected to the attachment, so that they can be exchanged after use for a fresh pipette tip. As a result contamination can be avoided during subsequent metering. Single use pipette tips are available cheaply, made from plastics.
[0005] The attachment for fastening pipette tips is frequently a cylindrical or conical projection relative to a base body or a housing, and onto which a pipette tip with a suitable mounting opening or receiver can be clamped. This can take place without grasping the pipette tip by pressing the attachment into the mounting opening of the pipette tip which is ready in a holder.
[0006] To avoid contamination of the user, pipette devices comprise an ejection device with a drive device and a throw-off device. By actuating the drive device the throw-off device is displaced, such that it releases the pipette tip from the attachment, without it having to be grasped by the user. Frequently, the drive device has a mechanism which has to be manually actuated by means of an actuation button, in order to release the pipette tip from the attachment. Drive devices are also possible with an electromotive drive. Releasing the pipette tip from the attachment can require increased operating force, in particular with pipette tips which are rigidly clamped onto the attachment. Even with one-channel systems, ie pipetting devices which comprise a single attachment for a single pipette tip, this can make ejecting the pipette tip from the attachment difficult or impossible. Particularly high operating force can be required with multi-channel pipette systems which have a plurality of parallel attachments for mounting pipette tips, due to multiple tip ejection forces.
[0007] A pipette system with an axially movable throw-off device for releasing a pipette tip from an attachment, a drive device to drive the axial movements of the throw-off device and a pull-means gear, push-means gear or linkage gear transferring an axial drive movement of the drive device into an axial movement of the throw-off device is known from EP 0 992 288 A2. The force exerted by the throw-off device on the pipette tip exceeds the force exerted by the user, whereby the ejection is facilitated.
[0008] Air cushion pipettes can lead to contamination of the displacement device. Penetration of fluid due to improper handling or the rising of vapour or tiny droplets of the liquid to be pipetted into the displacement device can result therefrom. Moreover, it can be desirable to exchange the displacement device in order to prepare the pipetting device for use in a further area of the volume of liquids to be pipetted.
[0009] Pipetting devices are already known in which the displacement device with the attachment for mounting the pipette tip can be separated from a drive device to drive the displacement device. In EP 0 428 500 B1 such a pipetting device is disclosed in which the displacement device can be screwed onto a shank of the drive device by means of a coupling nut. In principle, it is therefore possible to release the displacement device for cleaning or for exchanging the drive device. The fastening is nevertheless laborious, time-consuming and susceptible to faults.
[0010] Proceeding from this, the object of the invention is to provide a pipetting device in which the displacement device and the drive device can be more easily and more rapidly connected to and separated from one another and in which the connection is less susceptible to faults.
[0011] The object is achieved by a pipetting device with the features of claim 1 . Advantageous embodiments of the pipetting device are revealed in the sub-claims.
BRIEF SUMMARY OF THE INVENTION
[0012] The pipetting device according to the invention has a displacement device with a displacement chamber with a displaceable limiter, an attachment for connecting to a pipette tip and a connection channel between the displacement chamber and the free end of the attachment, a drive device for driving the displaceable limiter of the displacement device with a drive member which cooperates releasably with the displaceable limiter, and a bayonet connection between the drive device and the displacement device which can be established by producing the cooperation between the drive member and the displaceable limiter and can be released by releasing the cooperation between the drive member and the displaceable limiter.
[0013] The displacement device and the drive device of the pipetting device can be easily connected to one another by being pushed together along a longitudinal axis of the bayonet connection and rotating about the longitudinal axis of the bayonet connection and can be separated from one another in the reverse manner. When establishing the bayonet connection the cooperation between the drive member and the displaceable limiter is simultaneously produced without it requiring further particular actions therefor. When releasing the bayonet connection, the cooperation is released without particular further actions. The invention allows a particularly simple, rapid and secure connection and separation of the displacement device and the drive device, for example during assembly, before autoclaving or other cleaning of the lower part, before exchanging the lower part for the purpose of altering the working area, repairs, etc. The bayonet connection is not particularly susceptible to faults. These advantages are in particular effective when manually and automatically connecting and separating the displacement device and the drive device. The latter, for example, with automatic assembly or a workstation with automatic tool exchange.
[0014] The drive device can be designed in different ways. It makes use of technical means to displace the drive member, such that it displaces the displaceable limiter of the displacement device. To this end, the drive member carries out, for example, a linear movement. Accordingly, the drive device comprises a linear drive. In this connection there is, for example, a lifting rod which can be manually actuated directly by actuating a button or a lifting rod which is linearly displaceable via an electric drive motor and a gear mechanism. A pneumatically or hydraulically operated pressure medium cylinder can also be considered as the drive for the lifting rod which is actuated via a pneumatic or hydraulic control mechanism and a pressure medium reservoir. If the drive member does not carry out a linear movement but a three-dimensional feed motion, the drive device comprises a corresponding drive.
[0015] The drive device preferably comprises a housing in which the drive and the drive member are arranged. According to an embodiment, the drive member is a lifting rod of the drive device, displaceable parallel to the longitudinal axis of the bayonet connection and the displacement device comprises a contact surface connected to the limiter, oriented transversely to the lifting rod and which is pressed by a lift spring against the end of the lifting rod. In this embodiment the cooperation between the drive member and the displaceable limiter is automatically produced when the bayonet connection is established and automatically released when the bayonet connection is released.
[0016] According to an embodiment the contact surface is constructed on a pressure piece connected to the displaceable limiter via a rod and the lift spring is designed as a coil spring which at one end is supported on the pressure piece and at the other end on the displacement chamber.
[0017] The bayonet connection can be designed in different ways. Included in the invention in particular is the design of the drive device as a male part and the displacement device as a female part of the bayonet connection and vice versa. According to an embodiment the drive device has a cylindrical receiver which comprises an aperture at one end through which the cylindrical receiver is externally accessible in the axial direction which comprises at least one axially oriented longitudinal groove which is connected to an annular groove oriented in the peripheral direction of the cylindrical receiver and the displacement device on a cylindrical portion comprises at least one outwardly protruding projection, the cylindrical portion able to be inserted in the axial direction of the cylindrical receiver through the aperture into the receiver and with the projection into the longitudinal groove and can be screwed with the projection into the annular groove. In this embodiment the drive device is the female part and the displacement device the male part.
[0018] According to an embodiment the annular groove comprises, at a distance from the longitudinal groove, a limiting wall extended in the axial direction of the receiver, as far as which the projection can be rotated. Reaching the limiter indicates to the user that the bayonet connection has been established.
[0019] According to an embodiment, the annular groove is connected, at a distance from the longitudinal groove, to a longitudinal groove portion extending parallel thereto, which ends at a distance from the aperture. By engaging the projection into the longitudinal groove portion the reliability of the bayonet connection is effected.
[0020] According to an embodiment, the annular groove has a limiting wall extending in a ramp-like manner, of which the distance from the aperture increases with increasing distance from the longitudinal groove. The ramp-like path of the limiting wall facilitates finding the connection position and the separation of the displacement device from the drive device.
[0021] According to an embodiment the longitudinal groove, the annular groove and optionally the longitudinal groove portion are constructed in a cylindrical coupling piece which forms the receiver of the drive device and is fastened therein. As a result the manufacture, assembly and disassembly are facilitated.
[0022] According to an embodiment the drive device comprises a spring which presses against the displacement device connected to the drive device via the bayonet connection. As a result the bayonet connection is secured.
[0023] According to an embodiment, the spring is arranged on a further aperture of the receiver which is positioned opposite the aperture for axially inserting the displacement device. The displacement device and the spring act upon one another through this aperture. According to a further embodiment, the spring is a coil spring which is supported on an inner front face of the coupling piece.
[0024] According to an embodiment the longitudinal groove and/or the annular groove and/or the longitudinal groove portion are opened toward the further aperture.
[0025] According to an embodiment, the displacement device is a piston-cylinder-unit with a cylinder and a piston displaceable therein and the piston comprises the displaceable limiter. Other displacement devices are also included in the invention, for example a displacement chamber with a resilient wall forming the displaceable limiter. A piston-cylinder-unit is, for example actuated by a linear drive device. A corresponding actuation is possible with a displacement chamber with a resilient wall. The latter can also however be controlled via a drive device with a three-dimensional drive motion. Thus it is possible, for example, to control the resilient wall externally by acting upon a hydraulic or pneumatic pressure means.
[0026] According to an embodiment the attachment is aligned coaxially to the longitudinal axis of the bayonet connection. According to a further embodiment the attachment is rigidly connected to the displacement device.
[0027] According to an embodiment the pipetting device has an ejection device for ejecting a pipette tip from the attachment which comprises an ejection drive arranged on the drive device, a throw-off device arranged on the displacement device and a releasable axial clamping connection between the ejection drive and the throw-off device oriented in the direction of the longitudinal axis of the bayonet connection. The clamping connection can be established at the same time as the creation of the bayonet connection at the stage of the displacement device and the drive device being axially pushed together and can be released in the reverse direction.
[0028] According to an embodiment the ejection drive comprises an ejection rod protruding from the drive device parallel to the bayonet connection and the throw-off device comprises an axial bore parallel to the attachment and with which the ejection rod has an interference fit.
[0029] According to an embodiment, the throw-off device is carried on the displacement device.
[0030] According to an embodiment, the throw-off device is a sleeve carried on the displacement device.
[0031] According to an embodiment, the pipetting device is a hand-held device and/or a stationary device and/or an electrically driven device and/or a (semi) automatic machine. In the embodiments as a hand-held device the pipetting device is manually taken to the point where samples are taken and dispensed and the suctioning and dispensing of liquid and the actuation of the ejection device controlled manually. The drive devices for the displacement device and/or the throw-off device are of mechanical and/or electromechanical design. The latter also applies to the design of the pipetting devices as stationary devices. When designing the pipetting device as a (semi) automatic machine all functions or a portion of the functions of the pipetting devices (suctioning and dispensing liquid, movement of the pipetting devices into positions for receiving and dispensing liquid or pipette tips, receiving and dispensing of pipette tips) are carried out automatically.
[0032] According to an embodiment, the pipetting device comprises a row of parallel attachments to receive pipette tips. In this case it is a multi-channel pipetting system. A special or common displacement device is associated with each attachment of the pipetting device which is connected to the drive device via a bayonet connection. In addition, there can be a common drive device for all the displacement devices.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0033] The invention will be described in more detail hereinafter with reference to the accompanying drawings of embodiments, in which:
[0034] FIG. 1 is a hand-operated pipetting device with separate piston-cylinder-unit and throw-off device in longitudinal section;
[0035] FIG. 2 is the same pipetting device with attached piston-cylinder-unit and throw-off device in longitudinal section.
DETAILED DESCRIPTION OF THE INVENTION
[0036] While this invention may be embodied in many different forms, there are described in detail herein a specific preferred embodiment of the invention. This description is an exemplification of the principles of the invention and is not intended to limit the invention to the particular embodiment illustrated
[0037] The terms ‘above’, ‘below’, ‘horizontally’ and ‘vertically’ refer to the alignment of the pipetting device according to the drawings. In this connection it refers to an alignment of the pipetting device in which the pipette tip is arranged with its tip orifice below, in order to draw in liquid from a container located below the pipetting device and to dispense it into such a container.
[0038] The pipetting device according to FIGS. 1 and 2 has an elongate housing 1 formed as a grip with a housing upper part 2 and a housing lower part 3 . The housing upper part 2 with all the parts contained therein forms a drive device and the housing lower part 3 with all the parts contained therein forms a displacement device. The housing upper part 2 has a screw cap 4 above. An adjustable sleeve 5 protrudes upwardly therefrom. The adjustable sleeve 5 is axially fixedly and rotatably mounted in the housing upper part 2 .
[0039] In the adjustable sleeve 5 a push button 6 is arranged which protrudes even further upwardly.
[0040] The push button 6 is connected to a lifting rod 7 through which a spindle 8 is passed in the housing upper part 2 . The spindle 8 is screwed into an internal thread 9 of a bearing body 10 fixed in the housing upper part 2 .
[0041] Above, the spindle 8 comprises a tappet 11 connected rotationally fixedly thereto. The tappet 11 has on the periphery two diametrically opposing radial projections 12 . The radial projections 12 engage in axially extending grooves—not shown—of the adjustable sleeve 5 .
[0042] Below, the spindle 8 has an end stop 13 in the form of radially outwardly protruding ribs. In the position shown, the end stop 13 is located a small distance below a shoulder 14 of the bearing body 10 , with which it cooperates.
[0043] The lifting rod 7 has a flange 15 which bears against the spindle 8 below in the position shown.
[0044] At the lower end of the bearing body 10 a spring retainer 16 is arranged, which engages in the bearing body 10 with a collar 17 . Below, the spring retainer 16 has an axially protruding sleeve-shaped bearing portion 18 through which the lifting rod 7 is passed.
[0045] Moreover, the pipetting device comprises a spring, not shown, which presses the lifting rod 7 upwardly, so that the flange 15 bears against the lower face of the spindle 8 . For example, a coil spring is arranged between the flange 15 and the spring retainer 16 .
[0046] At a distance below the spring retainer 16 a coupling piece 19 is fastened in the housing. This has a plurality of pockets 20 inside. These have a longitudinal groove 21 extended axially over the entire length of the coupling piece 19 . Moreover, they have on the upper end of the coupling piece 19 an annular groove 22 extended over a small part of the periphery of the coupling piece 19 . Below, it has a limiting wall extending in a ramp-like manner at a distance from the upper end of the coupling piece 19 , which from the longitudinal groove 21 increasingly approaches the upper end of the coupling piece 19 . Finally, the pockets 20 have at the other end of the annular groove 22 a short axial longitudinal groove portion 23 which ends at a distance from the upper end of the coupling piece 19 in the coupling piece 19 .
[0047] Between the spring retainer 16 and the coupling piece 19 a spring 24 is arranged under preload which is designed as a coil spring.
[0048] The adjustable sleeve 5 has on its periphery a sprocket 25 which cooperates with a gear 26 which drives a counter 27 with a plurality of counter wheels 29 arranged over one another on an axis 28 . The counter wheels 29 are respectively numbered from 0 to 9. The lower counter wheel 29 is driven by the gear wheel 26 . The counter wheels 29 arranged thereover are respectively rotated further by a number when the counter wheel 29 arranged thereunder moves from 9 to 0.
[0049] The housing lower part 3 can be releasably connected to the housing upper part 2 . To this end the housing lower part 3 comprises on the casing of an upper, cylindrical portion 30 a plurality of outwardly protruding projections or ribs 31 which extend in the axial direction of the cylindrical portion 30 .
[0050] The housing lower part 3 has a plurality of conical portions 31 to 33 of varying lengths and taper below the cylindrical portion 30 which are revealed in the drawings. The conical portion 33 is connected below to a long, slightly conical attachment 34 for mounting a pipette tip. This again has a short, more conical mounting end 35 below.
[0051] The housing lower part 3 houses a displacement device in the form of a piston-cylinder-unit 36 . This has a cylinder 37 arranged in the conical portion 32 and in which a piston 38 dips. The piston 38 is connected above to a pressure piece 40 via a piston rod 39 . The piston 38 forms a displaceable limiter of the cylinder 37 .
[0052] Above the pressure piece 40 the housing lower part 3 has a piston holder 41 which spans the cylindrical portion 30 above. The piston holder 41 has a central through passage 42 above, through which a lower portion of the reciprocating piston 7 can be axially passed. Between the pressure piece 40 and the conical portion 31 a lift spring 43 is arranged which is designed as a coil spring. The piston 38 and the piston rod 39 are passed through the lift spring 43 .
[0053] The lift spring 43 is biased and presses the pressure piece 40 against the piston holder 41 , so that the piston 38 is pulled out to a maximum extent from the cylinder 37 .
[0054] A connection channel 44 extends through the attachment 34 and connects the cylinder 37 with an orifice in the mounting end 35 .
[0055] Moreover, the pipetting device has an ejection device 45 . The ejection device 45 has an actuation button 46 in the housing upper part 2 in addition to the adjustment button 5 . The actuation button 46 is connected to an ejection rod 47 which extends parallel to the lifting rod 7 through the housing upper part 2 .
[0056] A gear mechanism 48 is incorporated in the ejection rod 47 . The gear mechanism 48 converts an axial actuation stroke of the actuation button 46 into a smaller drive stroke with increased force. Suitable gear mechanisms 48 are disclosed in EP 0 992 288 A and namely generally in the main part of the description and especially in the description of the Figures which are included in the present application by reference.
[0057] The ejection rod 47 is supported in the housing upper part 2 via a further coil spring 49 , so that the actuation button 46 is pressed into the shown initial position into which it can be pressed against the effect of the further coil spring 49 .
[0058] The lower end of the ejection rod 47 protrudes into a receiver 50 at the lower end of the housing upper part 2 .
[0059] The ejection device 45 has an ejection sleeve 51 on the housing lower part 3 . This is carried on the cylindrical portion 30 , the conical portion 32 and the attachment 34 . Accordingly, the contour of the ejection sleeve 51 is similar to the contours of the aforementioned portions of the housing lower part 3 . In this connection the ejection sleeve 51 has inner steps 52 , 53 which upwardly limit the pushing up of the ejection sleeve 5 1 , as they bear against conical portions 31 , 33 of the housing lower part 3 .
[0060] Moreover, the ejection sleeve 51 has a lateral projection 54 on the upper edge which comprises an axial bore 55 for pressing in the lower end of the ejection rod 47 .
[0061] The pipetting device can be used in the following manner:
[0062] The housing upper part 2 and the housing lower part 3 can be connected by axially inserting and rotating the lower part 3 in the coupling piece 19 . As a result, a bayonet connection is established. Then the ribs 31 are pushed into the longitudinal grooves 21 , rotated through the annular grooves 22 and pushed into the short longitudinal groove portions 23 . In this connection, the spring 24 presses against the upper edge of the cylindrical portion 30 , whereby the housing lower part 3 is fixed in its fastening position, in which the ribs 31 bear against the lower ends of the longitudinal groove portions 23 which form a stop. Moreover, the ejection sleeve 51 with the bore 55 is pressed onto the lower region of the ejection rod 47 . The housing upper part 2 and the housing lower part 3 can be disassembled in the reverse manner.
[0063] After connecting the housing upper part 2 and the housing lower part 3 the lifting rod 7 engages through the through passage 42 and bears with its lower end against the pressure piece 40 .
[0064] To adjust a volume to be pipetted, the adjustable sleeve 5 is rotated until the counter 27 indicates the desired volume. When rotating the adjustable sleeve 5 the tappet 11 is rotated therewith due to the radial projections 12 . As a result the spindle 8 rotates in the internal thread 9 and is displaced axially in the housing upper part 2 by driving the flange 15 and therefore the lifting rod 7 . The radial projections 12 are therefore axially displaced along the grooves on the inner face of the adjustable sleeve 5 . As a result, the stroke of the lifting rod 7 is altered, which can take place during actuation of the push button 6 .
[0065] Moreover, on the lower end of the attachment 34 a pipette tip 56 is clamped. The pipette tip 56 has a lower tip aperture 57 for suctioning and dispensing liquid.
[0066] When mounting the pipette tip 56 on the attachment 34 , the mounting force increases as it is mounted further. If the mounting force exceeds the force with which the spring 24 is biased, the attachment 34 and thus the entire housing lower part 3 is pressed upwardly against the effect of the spring 24 . When the upper edge 58 of the pipette tip 56 presses the lower edge forming a stop 59 of the ejection sleeve 51 , a further raising of the housing lower part 3 is prevented, as the ejection sleeve 51 bears against a limiter 60 in the receiver 50 of the housing upper part 2 above. The mounting force and thus the ejection force required for ejection are thus limited to a specific value.
[0067] For pipetting, the push button 6 is pressed down, so that the piston 38 forces air out of the cylinder 37 . Then the pipette tip 56 is dipped with its lower tip orifice 57 into the liquid to be pipetted. Then, the push button 6 is released and the lifting rod 7 returns into its initial position under the action of the spring. The piston 38 also returns into its initial position under the action of the spring 43 . Then the piston 38 suctions liquid through the lower tip orifice 57 into the pipette tip 56 .
[0068] Afterwards, the lower tip orifice 57 of the pipetting device is aligned with a dispensing position. The liquid contained in the pipette tip 56 is dispensed by pressing in the push button 6 , further dipping of the piston 38 into the cylinder 37 and pressing air out through the connection channel 44 . After releasing the actuation button 6 , the lifting rod 7 and the piston 38 return again to the initial position by spring force.
[0069] To eject the pipette tip 56 , the actuation button 46 is pressed. As a result the ejection sleeve 51 moves downwardly and pushes the pipette tip 56 away from the attachment 34 .
[0070] 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.
[0071] Further, the particular features presented in the dependent claims can be combined with each other in other manners within the scope of the invention such that the invention should be recognized as also specifically directed to other embodiments having any other possible combination of the features of the dependent claims. For instance, for purposes of claim publication, any dependent claim which follows should be taken as alternatively written in a multiple dependent form from all prior claims which possess all antecedents referenced in such dependent claim if such multiple dependent format is an accepted format within the jurisdiction (e.g. each claim depending directly from claim 1 should be alternatively taken as depending from all previous claims). In jurisdictions where multiple dependent claim formats are restricted, the following dependent claims should each be also taken as alternatively written in each singly dependent claim format which creates a dependency from a prior antecedent-possessing claim other than the specific claim listed in such dependent claim below.
[0072] 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. | Pipetting device with a displacement device with a displacement chamber with a displaceable limiter, a attachment for connecting to a pipette tip and a connecting channel between the displacement chamber and the free end of the attachment, a drive device for driving the displaceable limiter of the displacement device with a drive member, which has a releasable cooperation with the displaceable limiter, and a bayonet connection between the drive device and the displacement device which can be established by creating the cooperation between the drive member and the displaceable limiter and can be released by releasing the cooperation between the drive member and the displaceable limiter. | 1 |
BACKGROUND OF THE INVENTION
It has long been known to nitrate aromatic and substituted aromatic compositions for producing a variety of products which are useful as intermediates in the chemical industry. For example, toluene is nitrated to form an intermediate, i.e., paranitrotoluene, which is useful for the preparation of dyestuffs and drugs intermediates. A dinitrotoluene, a mixture of 2, 4 and 2,6-dinitrotoluene has been employed in the manufacture of toluene diisocyanate which is useful for the formation of polyurethanes.
It is known that in the nitration of mono-substituted aromatic compositions that 3 isomers can be formed and the proportion of each isomer formed often is largely dependent upon the functional group present on the aromatic ring. For example, when toluene is nitrated, approximately 58% of the ortho-isomer, 38% of the para-isomer and 4% of the metaisomer are formed whereas when chlorobenzene is nitrated about 30% of the product is the ortho-isomer and 70% is the para-isomer. Even though specific groups on the aromatic ring can assist in the formation of a larger proportion of appropriate isomers, these groups may not be desired in the final product or they may not provide sufficient selectivity.
The presence of a plurality of isomers in the nitration mixture may be undesirable and can lead to economic waste in terms of the materials consumed and in terms of recovery or disposal. For example, with respect to nitrotoluene, paranitrotoluene is useful, while the ortho and meta-nitrotoluene isomers are not as useful, in the preparation of dyestuffs and drug intermediates. Thus, these isomers must be removed from the product which adds to the cost.
For end uses in the polyurethane industry a high ratio of 2, 4-dinitrotoluene to 2, 6-dinitrotoluene is desired. Some 2, 6-isomer of dinitrotoluene is produced by nitrating orthonitrotoluene whereas solely the 2, 4-dinitrotoluene isomer is produced from para-nitrotoluene which again shows the importance of obtaining para-nitrotoluene. The isomers produced from meta-nitrotoluene are unacceptable in many of the polyurethane applications and thereby represent a problem in terms of purification, i.e., removal of the meta-nitrotoluene from the product.
Another substituted aromatic compound, i.e., 4-nitro ortho-xylene is highly useful and desirable in many applications in the chemical industry. When orthoxylene is conventionally nitrated, approximately equal amounts of 4-nitro ortho-xylene and 3-nitro ortho-xylene are formed. The 3-nitro isomer generally is removed from the product which adds to the cost and leads to waste.
DESCRIPTION OF THE PRIOR ART
For a considerable time practitioners in the art of nitration have sought methods for not only enhancing the rate of nitration of aromatic and substituted aromatic composition, but the selectivity of nitration, e.g., the para position, on the aromatic molecule.
Many catalysts or promoters have been developed and used for enhancing the nitration reaction but many did not enhance the selectivity of nitration. Cataylsts or promoters are required for achieving a rate of nitration acceptable for commercial production. These rates cannot be attained simply by increasing the concentration of the reactants.
In a conventional method of nitration of an aromatic or a substituted aromatic compound, nitric acid is mixed with concentrated sulfuric acid and added in liquid phase to the aromatic composition. The sulfuric acid is added to the nitric acid to permit formation of nitronium ions which can attack the aromatic ring for effecting nitration thereby catalyzing the reaction. As the reaction proceeds water is formed and dilutes the sulfuric acid. Accordingly, the sulfuric acid must be replenished to bring it to an acceptable concentration for catalyzing the reaction.
Aromatic sulfonic acids have been used to promote selectivity of niration, particularly at the para position in the nitration of toluene. The aromatic sulfonic acids can be in molecular form or they can be attached to a polymer network i.e., an ion exchange resin. These aromatic sulfonic acids, although suited for enhancing selectivity of the nitration of toluene, suffer from certain disadvantages. They are often difficult to regenerate and the sulfonic acids have very little capacity in terms of the sulfonic acid required per part of product produced before regeneration is required. An unsupported sulfonic acid presents problems in that it frequently is soluble in the product and makes separation more difficult.
Another approach suggested for enhancing selectivity of nitration at the para position in toluene is through the use of nitrate esters of highly hindered alcohols. The basic problems with this method are (a) the carrier is quite costly, (b) there are difficulties in regenerating the alcohol after nitration, and (c) there is the possibility of losing the carrier alcohol by rearrangement under the acid conditions necessary for nitration.
Another variation in the conventional nitration process has been suggested which employs lower temperatures and stronger nitric acid mixtures than are customarily employed for nitration. This is particularly true for toluene. The problem with this technique is that it results in the formation of a large proportion of dinitrotoluene as well as mononitrotoluene. Even though a large proportion of the desired isomer is formed, the reaction medium is not well suited for the synthesis of the mono nitrotoluene.
SUMMARY OF THE INVENTION
This invention relates to an improvement in a process for nitrating an aromatic or substituted aromatic composition wherein nitric acid is contacted with the composition under conditions for effecting nitration thereof. The improvement for enhancing the rate of nitration as well as the selectivity of the nitration comprises carrying out said nitration in the presence of at least an effective amount of soluble anhydrite for increasing the nitration or the selectivity of the nitration.
Advantages of this process include:
a. The ability to carry out the nitration at moderate temperatures, e.g., room temperature (25° C.) at enhanced reaction rates as compared to non-catalyzed nitration methods;
b. The ability to enhance the selectivity of the nitration particularly in the alkyl aromatic compositions, e.g., toluene at the para position; and
c. The use of a relatively cheap promoter or catalyst which can be recovered and regenerated easily for subsequent use.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Broadly, the aromatic and substituted aromatic compositions typically suited for nitration and practicing this invention are represented by the formula: RC 6 H 4 R 1 wherein R is a lower alkyl radical having from 1-4 carbon atoms, halogen, haloalkyl, nitro, or--OCH 3 group and R 1 is a lower alkyl radical having from 1-4 carbon atoms, halogen, nitro, or hydrogen group preferably hydrogen. Of these compositions the lower alkyl aromatic, polyalkylaromatic, and the halo alkyl aromatic compositions are best suited for practicing the invention. The nitration reaction products of these compositions have wide usage in the chemical industry, and thus enhanced nitration rates or selectivity of the nitration at the para position or both may be important.
The aromatic ring can be substituted as shown in the formula, with a wide variety of groups. These groups should be sufficiently inert to the nitration reaction so that they do not substantially interfere with the nitration of the aromatic ring. Common aromatic and substituted aromatic compositions contemplated for practicing this invention are toluene, ortho-xylene, n-propyl benzene, isopropyl benzene, t-butylbenzene, n-butyl benzene, ortho-chlorotoluene, ethyl benzene, ortho-nitrotoluene, meta-xylene, benzene, and nitrobenzene.
The catalyst or promoter employed in the practice of this invention and used for enhancing the rate of nitration or the selectivity of nitration at the para position or both is anhydrous calcium sulfate or soluble anhydrite as it is sometimes called. Soluble anhydrite is made by heating gypsum, CaSO 4 .2H 2 O which is dried, crushed, sized and heated to about 450° to 500°F for 2 hours. The resulting product is a soluble, granular, porous product having sufficient mechanical strength to support its own weight. Soluble anhydrite readily takes on water, in moist air to form calcium sulfate hemi-hydrate, CaSO 4 .1/2H 2 O and has been used as a dessicant and sold under the trademark "Drierite."
The Drierite catalyst is added to the reaction medium in a proportion at least sufficient to increase the rate of nitration or to influence the selectivity of the nitration or both. However, proportions of this magnitude generally are not sufficient for achieving preferred results for enhancing selectivity of the nitration, particularly with toluene, or forming the para isomer. Generally, at least 25% of the stoichiometric amount required for nitration, based on the theoretical quantity of nitrated product, is added to the reaction medium and this proportion can be increased to at least 500% in excess of the theoretical stoichiometric amount based on the nitrated product. Preferably the proportion of soluble anhydrite which is added to the nitration reaction is at least the theoretical stoichometric requirement. When less than 25% of the stoichometric quantity of soluble anhydrite is employed, then the advantages, in terms of rate of reaction or selectivity of nitration at the para position, may be reduced. As the proportion of soluble anhydrite is increased above 25% to the stoichiometric requirement, then enhanced rate and selectivity advantages are noticed. When the proportion of soluble anhydrite is increased above the theoretical stoichiometric requirement, then disadvantages appear. These disadvantages include increased cost of material, in terms of the magnitude of the material to be removed and regenerated. Preferably at least a stoichometric amount to about 100% in excess of soluble anhydrite is used.
The stoichiometric quantity of soluble anhydrite to be used for the nitration (assuming anhydrous conditions) is determined in this way. One mole of water is produced for each mole of mononitrated aromatic or substituted aromatic compound produced. 1 mole of soluble anhydrite can absorb 1/2 mole water. Thus, the stoichiometric quantity requires that two moles of soluble anhydrite be employed for each mole of mononitrated aromatic or substituted aromatic composition produced. If the dinitrated aromatic or substituted aromatic composition is desired, then stoichiometrically four moles soluble anhydrite are required to absorb the 2 moles water generated by the dinitration reaction. For convenience, the reference point (assuming anhydrous nitric acid is employed) used is the theoretical quantity of water that would be produced if all of the nitric acid reacted. Otherwise the amount of soluble anhydrite must be increased to compensate for water in the nitric acid as diluent.
Although not intending to be bound by theory, it is believed that the soluble anhydrite, because of its tremendous affinity for water, removes water from the nitric acid to form nitronium ions. These nitronium ions can attack the aromatic ring to effect nitration. On the other hand, other dessicants, e.g., silica gel and plaster of paris have not resulted in enhancing the rate of nitation to the extent obtained by the use of soluble anhydrite nor do they enhance nitration at the para position in toluene.
Calcium sulfate hemi-hydrate which is formed by the soluble anhydrite absorbing one-half mole water can be regenerated into the soluble anhydrite form by conventional techniques. Typically, the calcium sulfate hemi-hydrate is heated to 400° to 425°F. with a stream of hot air. One of the advantages of soluble anhydrite in practicing this invention is that it can be used many times before it must be discarded to waste.
The reaction conditions suited for effecting nitration of this invention generally are the same as those conventionally used in the past except for the addition of soluble anhydrite. For example, temperatures as low as 0° C. and up to about 125° C. can be employed. Through experimentation it has been found that the proportion of the para isomer produced, in the case of toluene, is lower when made at higher temperatures e.g., 100° C. than the proportion produced at lower temperatures e.g., 25° C. However, the proportion of para-isomer formed at higher temperatures is greater where the soluble anhydrite is included in the reaction medium than the proportion of para-isomer produced at the same temperature by conventional techniques. Pressure suited for practicing this invention can vary from subatmospheric to superatmospheric although atmospheric pressures are preferred for reasons of efficiency and economy.
Because Drierite or soluble anhydrite absorbs only 6.6% of its weight of water, the large scale reaction of toluene and nitric acid in stoichiometric ratio generally requires the use of a diluent to provide a tractable reaction mixture. Compounds such as chloroform methylene chloride, nitrotoluene, and the like can be used. Preferably the reactants should be highly soluble in the diluent in order to achieve preferred results. Diluents which are not solvents for the reactants tend to reduce the rate and selectivity of the nitration. The diluent can have an effect on the rate of nitration and selectivity, but the results typically are better than conventional nitration techniques. For example, chloroform results in lower ortho-para ratios than methylene chloride, but both give lower ratios than are obtained in conventional nitration.
Using the reaction conditions above, the nitration can be carried out preferably with conventional reactants for nitration. Typically, nitric acid in a concentration of from 30 to 100% is used as the nitrating agent. Preferably anhydrous nitric acid is employed as this reduces the amount of water in the system. Nitric acid can also be generated in situ by employing an alkali metal nitrate and an acid e.g., sulfuric.
The following examples are provided to illustrate preferred embodiments of this invention and are not intended to restrict the scope thereof. All percentages are expressed as weight percentages and all temperatures are in degrees centigrade.
EXAMPLE 1
A 60 ml portion of toluene was treated with an 80 ml portion of a mixed acid consisting of 34 mole percent concentrated sulfuric and 8 mole percent concentrated nitric acid. Treatment was effected by spraying the acid through the toluene from a syringe. The temperature of the reaction was maintained at about 25° C.
A sample of the toluene so treated was taken and divided into two parts. Sample I was the control. To Sample II was added 0.23 grams soluble anhydrite (Drierite) per milliliter of reaction medium. At the end of 1 hour the samples were analyzed by gas chromotography and also at the end of a 24 hour period. The analyses showed the composition of both the control and experimental samples to be about the same at the end of 24 hours as at the end of one hour, thus showing most of the reaction was completed in one hour. The compositions below represent the analyses of the Samples I and II at the end of the 1 hour period.
TABLE I__________________________________________________________________________ Untreated 100% Isomer 100% Isomer mole % in sample Corrected to mole % in sample Corrected to (balance toluene) 100% MNT (balance toluene) 100% MNT SAMPLE I SAMPLE I SAMPLE II SAMPLE II__________________________________________________________________________ortho 0.373% 52.2% 1.197% 41.5%meta 0.025 3.9 0.070 2.4para 0.243 37.9 1.616 56.1Total MNT .641% 2.883%Ratio ortho/ 1.53 0.74para__________________________________________________________________________
The results show that Sample 1, which was the control sample, resulted in a production of only 0.641 mole percent mononitrotoluene whereas the treated sample containing the soluble anhydrite resulted in producing 2.883 mole percent mononitrotoluene. These results show that the addition of soluble anhydrite to the reaction medium enhanced the rate and the extent of nitration. The results also bear out the fact that the percent of the desired para-isomer formed after addition of the soluble anhydrite increased substantially. The ratio of ortho to para-isomer in Sample 2 was approximately 0.74 . Conventional nitration reactions involving toluene as exemplified by Sample I have a ratio of approximately 1.5 to 1.8 ortho to para-isomer. Thus, the results show that soluble anhydrite is effective for enhancing the selectivity or increasing the proportion of para-isomer formed during the nitration reaction of toluene.
EXAMPLE II
A 100 gram portion of the powdered, soluble anhydrite (Drierite) was added to 100 milliliters toluene and mixed therein. A 13.6 gram portion of anhydrous nitric acid was added to the mixture of toluene and soluble anhydrite drop by drop over a 30 minute period. After all of the nitric acid was added to the toluene-soluble anhydrite mixture, the reaction was permitted to continue for 3 hours at 25° C. Then 26 grams nitrobenzene was added to the reaction medium and the medium was stirred for an additional 30 minutes. The reaction medium then was filtered and the filtrate was analyzed by gas chromotography using the added nitrobenzene as the internal standard. Results showed that a yield of 89% mononitrotoluene, based on the nitric acid, was obtained.
Assuming that all of the nitric acid would react to form the mononitrotoluene product, it follows that 0.215 mole water would be produced. The quantity of soluble anhydrite added to the reaction medium was approximately 70% in excess of the theoretical stoichiometric quantity required for absorbing all the water that would be generated by the reaction. As it turned out, the quantity of soluble anhydrite, based on the water produced by the actual nitration, was 90% in excess of the stoichiometric quantity required for absorbing the actual water generated.
The mononitrotoluene composition produced above analyzed as follows: 43.2% ortho-nitrotoluene, 2.3% meta-nitrotoluene and 54.4% para nitrotoluene. The ratio of ortho to para isomer formed was 0.78 or about one-half of that obtained by conventional nitration techniques. It should also be noted that the quantity of meta-isomer formed was about one-half of that ordinarily formed by conventional nitration techniques. Thus the results show that the addition of soluble anhydrite to the reaction medium not only gave good yield in terms of the nitrotoluene produced, based on the nitric acid employed, but in terms of an increased proportion of the desired para isomer at the expense of the less desirable ortho and metaisomers.
EXAMPLE III
An 86 gram portion of soluble anhydrite regenerated from Example II by first heating in a vacuum at 100°C for 7 hours for removal of organic material and then over night at 200°C. was added to a 100 milliliter portion of toluene. This mixture was heated to 45°C. and stirred while an 18.1 gram portion of anhydrous nitric acid was added drop by drop over a 30-minute period. Agitation was continued for 1 1/2 hours, then a 26 gram portion of nitrobenzene was added to the reaction mixture and stirring was continued for an additional hour. After this one hour period, the reaction mixture was filtered and the filtrate analyzed by gas chromotography using the nitrobenzene as the internal standard. A yield of 61% mononitrotoluene was obtained based on the nitric acid charged. The mononitrotoluene had the following composition: 44.1% ortho-nitrotoluene, 2.8% meta-nitrotoluene, and 53.1% paranitrotoluene. Thus the results show a substantial increase in the proportion of para-isomer was obtained by the addition of the soluble anhydrite to the reaction medium.
Assuming that all the nitric acid is converted to mononitrotoluene, the quantity of soluble anhydrite added to the reaction medium was about 12% in excess of the theoretical stoichiometric quantity required for absorbing all of the water that would be generated. In actual practice, the quantity of soluble anhydrite added was about 80% in excess of the theoretical stoichiometric quantity necessary for absorbing the actual water generated.
EXAMPLE IV
A 100g portion of soluble anhydrite was added to a solution of 32.9g toluene in 100 ml chloroform. Then a 22.6g portion of anhydrous nitric acid was added to the dispersion over a 30-minute period. Stirring at 25°C was continued for an additional 2 1/2 hour period. Nitrobenzene was added before the last half hour period and was used as the internal standard. Gas chromatographic analysis showed a 93.2% yield of nitrotoluene with the proportion being 49.1% ortho, 2.1% meta, and 48.8% para.
EXAMPLE V
The procedures of Example II and Example III where noted were followed except that various compositions and reaction times as set forth in Table 2 were employed. The reactions were carried out at approximately 25°C. the quantity of soluble anhydrite employed was about 70% in excess of the theoretical stoichiometric quantity necessary for absorbing the water generated.
TABLE 2__________________________________________________________________________ YieldComposition Time (based on HNO.sub.3) Isomer Distribution__________________________________________________________________________o-xylene 16 hrs 39% 3-nitro-o-xylene 32% 4-nitro-o-xylene 68%m-xylene 5 hrs 62% 2-nitro-m-xylene 7.9% 4-nitro-m-xylene 92.1%chlorobenzene 16 hrs 87% o-nitrochlorobenzene 24% p-nitrochlorobenzene 76%o-nitrotoluene* 16 hrs ** 2,4-dinitrotoluene 69% 2,6-dinitrotoluene 31%benzene 31/2 hrs 42% nitrobenzene__________________________________________________________________________ *Procedure analogous to Example IV. **Not determined.
The results show that the soluble anhydrite was effective for selectively nitrating at the para position. For example, greater quantities of 4-nitro-ortho-xylene and 4-nitro-meta-xylene were obtained with ortho-xylene and meta-xylene by using the soluble anhydrite than were obtained by conventional nitration. Furthermore, nitration of chlorobenzene to the para isomer is enhanced and ortho-nitrotoluene yields enhanced selectivity to the 2-4-isomer. The results also show the ability of the soluble anhydrite for activating compositions of low reactivity e.g., chlorobenzene and ortho-nitrotoluene.
The procedure of Example II was followed except that a similar quantity of plaster of paris (CaSO 4 .1/2H 2 O) based on stoichiometric proportions was added to one sample and a similar quantity of silica gel based on stoichiometric proportions was added to another sample in place of the soluble anhydrite. The yield of mononitrotoluene, based on the nitric acid charged, at the end of a two hour period was small in the case of plaster of paris. The ratio of ortho-nitrotoluene to para-nitrotoluene isomer was 1.31. With respect to the sample employing the silica gel, the yield of mononitrotoluene, based on the nitric acid charged, over a 16 hour reaction period was 48%. The ratio of ortho-nitrotoluene to para-nitrotoluene isomer was 1.21.
These results show that silica gel and plaster of paris, even though commonly used dessicants, are not as effective as soluble anhydrite for enhancing the selectivity or the extent of the nitration reaction. Poorer nitration rates are manifest from the low yields obtained based on the nitric acid charged even though similar reaction times were employed. The results also show that the quantity of para-nitrotoluene isomer produced is substantially less than is produced when soluble anhydrite is employed. The ratios of the orthonitrotoluene to para-nitrotoluene, with both the plaster of paris and silica gel, are about the same as obtained by conventional nitration techniques.
EXAMPLE VI
The procedure of Example II was followed except that 100 grams of macroreticular sulfonated polystyrene resin which is known and used as a catalyst, and sold under the trade name Amberlyst-15 was substituted for soluble anhydrite. The reaction time was increased to 6 hours. The yield of mononitrotoluene produced, based on the nitric acid charged, was 46%. The isomer distribution was as follows: 43.4% ortho-nitrotoluene, 3.1% meta-nitroluene, and 53.5% para-nitrotoluene.
Although the isomer distribution obtained by employing the sulfonated polystyrene resin was similar to that obtained by using soluble anhydrite, the yield of mononitrotoluene produced was much lower than was obtained with the soluble anhydrite. The yield of mononitrotoluene suggests that the sulfonated polystyrene resin catalyst is either less active than the soluble anhydrite in influencing or enhancing the rate of nitration or it has a smaller capacity. If the latter is true, then larger quantities of sulfonated polystyrene resin are necessary. | This invention relates to an improvement in a process for nitrating an aromatic or substituted aromatic compound e.g., toluene or ortho-xylene, by reacting such aromatic or substituted aromatic in the presence of nitric acid. The improvement for enhancing the rate of nitration as well as the selectivity of nitration at the para-position in this process comprises carrying out the nitration reaction in the presence of at least an effective amount of anhydrous calcium sulfate or soluble anhydrite. | 2 |
BACKGROUND OF THE INVENTION FIELD OF THE INVENTION
The invention relates to a gear box of a wind power plant, in particular a multi-stage gear box of a wind power plant, wherein the gear box comprises a gear box housing. Furthermore, the invention relates to a wind power plant and use of a work instrument.
DESCRIPTION OF RELATED ART
Wind power plants of the patent applicant are known under the description 5M, MM92, MM82, MM70 and MD77. The wind power plants can be erected both on the ground (onshore) or in bodies of water (offshore).
In the case of wind power plants, the rotors of the wind power plant are connected with a gear box and a generator via a drive train. The wind power plant hereby generally comprises a rotor shaft, on one end of which the rotor shaft is coupled with the rotor and on the other end of which the rotor shaft is coupled with the gearbox. The rotor blades of the wind power plant are fastened on a rotor hub, which is in turn connected with the rotor shaft. The rotational movement of the rotor is transferred to the gearbox via the rotor shaft so that the gearbox is in operative connection with a generator via a generator-side output.
In the case of generic wind power plants, the gear box can be multi-stage, wherein the gear box generally has one or more planetary stages and, if applicable, one or more gear box stages (spur wheel stages).
The first gear box stage of a multi-stage gear box for generic wind power plants is frequently designed as a planetary stage, wherein the rotor is coupled with the planet carrier or the hollow wheel of the planetary stage. The planetary stage hereby generally consists of a sun wheel, around which several planet gears meshing with the sun wheel are arranged, wherein the planet gears are mounted in a planet carrier. The sun wheel, the planet gears and the parts of the planet carrier are surrounded by a hollow wheel, wherein the hollow wheel is designed such that it meshes with the planet gears.
For example, DE-B-103 57 026 and DE-B-103 34 448 describe wind power plans with multi-stage gear boxes.
Based on this stage of the art, the object of the invention is to perform maintenance measures for a wind power plant in an, in particular multi-stage, gear box in a simple manner, wherein the time and construction effort should be kept as low as possible.
BRIEF SUMMARY OF THE INVENTION
This object is solved through a gear box of a wind power plant, in particular a multi-stage gear box of a wind power plant, wherein the gear box comprises a gear box housing, which is further developed in that at least one access opening is provided on the outside of the gear box housing for the insertion of a work instrument into the gear box housing or respectively into the interior of the gear box housing and in that at least one guiding means is provided for the work instrument inside the gear box housing so that the work instrument is movable and/or positionable within the guiding means, wherein in particular, parts of the gear box are checked or examined and/or worked by means of the work instrument inserted or arranged or arrangeable in the guiding means or at least one physical property of a medium, in particular of oil, in the gear box housing or physical properties of components of the gear box are detected or respectively are detectable.
The invention is based on the idea that in erected wind power plants the interior of a gear box, in particular a planetary gear box, can be examined, checked and/or worked, e.g. repaired, in a simple manner. For this, it is possible through the guiding means, e.g. a guide tube or empty tube, to insert a work instrument into the housing on a specific and defined guided track, wherein the work instrument can be a test device, a measurement device, a tool or a processing device so that the work instrument is positioned at predetermined locations or respectively on components in the gear box through an exact guidance of the work instrument in the guiding means, designed for example as a guide tube or hose in order to perform corresponding measures (examinations, inspections or if applicable repairs) with the work instrument. The corresponding work instruments are hereby arranged on the relevant components within the gear box, which are accessible based on the structural type.
For example, it is conceivable within the scope of the invention that the work instrument is designed as a heat sensor, e.g. infrared sensor or the like in order to capture or respectively detect the heat development on certain components of the gear box during the warm-up phase or operating phase or in the cool-down phase.
Through the guided positioning and precise guidance of the work instrument, using the empty guide tube or respectively empty tube, the work instrument is guided quickly and easily to the relevant components or spots inside the gear box housing since the work instrument is guided in a tubular manner through the guide tube during the insertion process. In this respect, it is no longer necessary to rely on the skill of the maintenance personnel and their sense of space to position the work instrument at the desired location within the gear box. In particular, positions that are difficult to access are reached quickly within the interior of the gear box due to the defined guidance of the work instrument through the empty tube.
A guide device for the work instrument is provided through the provided guide tube or respectively empty tube, which is arranged inside the gear box housing. Via the access opening provided on the outside of the gear box housing, the work instrument is inserted into the tube since the access opening and the inlet side of the guide tube work together or are arranged so that they communicate with each other.
It is thus possible, by means of the invention, to capture and document in a simple and fast manner the inner state of a gear box, for example through insertion of an endoscope into the guidance tube.
In a preferred embodiment, the guiding means for the work instrument in the gear box is constructed as a guide tube or respectively empty tube and/or as a guide hose. The guiding means for the work instrument is hereby designed or respectively installed at least in a tubular manner in sections and/or at least hose-like in sections inside the gear box housing. When discussing a guide tube within the scope of the invention, a guide hose is also included in the same manner. Furthermore, within the scope of the invention, a guiding means for the working instrument is a guide tube or a guide hose as well as a combination of the two guide devices into which the work instrument is inserted. The guide hose preferably has a predetermined elasticity so that the guide hose is bendable.
It is further provided for this that the cross-section of the guiding means, e.g. a guide tube, is constructed closed at least in sections so that the work instrument is hereby held within the tube during an insertion process into the guide tube or respectively empty tube in the longitudinal direction of the guide tube, whereby the interior of the guide tube is not freely accessible from outside in the sections and the work instrument, or respectively a section of the work instrument, is received within the close section. Within the scope of the invention, a guiding means with a closed cross-section is understood as a guide tube or hose so that the work instrument inserted into the guiding means during the insertion or respectively positioning process cannot deviate laterally or respectively transversely to the guide direction and remains arranged in the guide tube or hose.
Through the invention, no structural measures or changes are made to the existing gear box parts inside the gear box since external guide tubes or guide hoses are arranged inside the gear box housing in addition to the existing gear box parts. For example, an endoscope is guided to mechanically stressed roller bearings in the gear box or respectively planetary gear box through the empty tube or, respectively, guide tube. Moreover, it is possible to inspect toothing areas of shafts or pinions or other mechanically highly stressed areas within the gear box.
Moreover, it is advantageous in one embodiment if the guiding means, e.g. guide tube and/or guide hose, is arranged inside the gear box housing at least in sections at or on fixed components of the gear box and/or at least the guiding means is arranged inside the gear box housing at least in sections at or on components of the gear box moving or moveable, in particular rotating or rotatable, with respect to the gear box housing. It is hereby possible that sections of the guiding means or respectively guide tube sections are arranged both on non-moving as well as on moving components inside the gear box, for example via spacers or the like, on the components, wherein the guide tube sections, which are arranged on moving components, are brought into predetermined positions so that this guide tube section works together with other guide tube sections, which are arranged for example on non-moving components, so that several guide tube sections result in a total of one guide tube through which one work instrument is inserted.
Furthermore, it is advantageous in one embodiment if the guide tube is made up of several sections. Guide tube sections, which are mounted permanently to the housing, and other sections, which are arranged on components of the gear box movable, in particular rotating, with respect to the housing, are preferably provided inside the gear box. It is hereby possible to position guide tube sections with respect to each other through rotation of the components so that they work with each other and so that, in these predetermined positions, several guide tube sections result in a total of one guide tube, which is inserted into the work instrument.
The arrangement on rotating and non-rotating components can preferably take place via, or respectively by means of, spacers or the like.
Furthermore, guide tubes can be provided, the sections of which are arranged on several components rotating at different speeds, which thereby are brought into a predetermined position so that they work together and with an access opening in the gear box housing so that a work instrument can be inserted.
Moreover, it is possible within the scope of the invention that a guide tube, which is arranged on a movable component of the gear box, is brought into a corresponding insertion position or, respectively, work position for the guide tube with respect to the access opening so that an endoscope, for example, is inserted into the gear box housing via the guide tube or respectively the empty tube in this fixed insertion position of the guide tube.
Furthermore, it is advantageous in one embodiment that the guiding means has several guiding means sections, such as tube sections and/or hose sections, which communicate with each other and are aligned or alignable with respect to each other, especially upon insertion of a or the work instrument into the guiding means. The guidance and positionability of the work instrument within the gear box housing, for example in a planetary gear box, is hereby facilitated.
Moreover, the insertion process and the handling of the work instrument are improved by the guiding means, e.g. guide tube, that comprises straight and/or bent guide means sections or respectively guide tube sections so that the work instrument is positionable accordingly on predetermined areas or components of the gear box.
Moreover, it is beneficial in one embodiment if openings, for example in the form of small perforation holes or openings, are provided in the guide tube or respectively guide hose so that gear box oil escapes from the guide tube or respectively the guide tube section for example during insertion of a work tool into the empty tube or respectively guide tube in order to not contaminate the work instrument and to keep it fully functional. During the insertion process, oil accordingly escapes from the openings or perforation openings in the guide tube wherein the work instrument is held within the inner wall of the guide tube. Pressure balance is achieved in a simple manner through the openings or respectively perforation holes when the guide tube section is arranged for example in an oil sump or the like.
Furthermore, it is particularly advantageous when the guiding means, in particular guide tube and/or guide hose, comprises an oil scraper device in particular on the end or at the outlet of the guide means inside or respectively in the gear box housing so that for example the optics of an endoscope as work instrument is freed. For example, the oil scraper device can thereby be designed with a sealing lip or rubber lip.
The object is also solved or respectively a further embodiment of the gear box is characterized in that at least one optical device, in particular a mirror or prism or the like, is arranged in the gear box housing or in that part of an optical device, in particular an endoscope, is arranged, in particular permanently in the gear box housing, wherein the interior of the gear box housing, in particular components of the gear box, are checked or are checkable using the optical device and using a work instrument inserted or provided in the gear box housing, in particular via a guide tube or empty tube or a guide hose or physical properties of media in the gear box, e.g. gear box oil or the like, or physical properties of components of the gear box are detected or are detectable. Due to the fact that mirrors or other optical devices are provided at predetermined positions inside the gear box housing, by means of which areas that are difficult to access for a work instrument, for example an endoscope, which is inserted into a guide tube arranged in the gear box housing for example through insertion, become visible, other areas of components relevant for the inspection or for maintenance measures also become visible using a work instrument.
Within the scope of the invention, it is possible that one or more components of an endoscope, e.g. the optics of an endoscope, are permanently arranged, i.e. permanently installed, in the gear box housing as the optical device and are also present or respectively remain in the gear box housing during operation of the gear box. In one embodiment, the provided guiding means is thereby used as holding devices or holders for the optical unit of an endoscope. For example, a part of an endoscope permanently arranged in the gear box is furthermore designed as a light conductor or light source.
In particular, for example in the area of the outlet side of the guiding means or respectively of the guide tubes, corresponding mirrors are arranged so that a rear area of a component, for example a planet carrier or the like, can be inspected in a quite simple manner through the deviation mirrors using the endoscope in the area of the deviation mirror(s). The optical devices, or respectively mirrors, can thereby be arranged on fixed and/or also on moving, i.e. rotatable or rotating, components, wherein no structural measures will be or respectively are performed on the components through the arrangement of the optical device or respectively mirrors.
Moreover, the gear box in a further embodiment is characterized in that the access opening, in particular for one or more separate guide means or respectively guide tubes, is constructed to be closable. For example, a cover or a closure can be provided for this in order to close the access opening so that, for example, no oil escapes from the gear box and no dirt penetrates the closed access opening while the gear box is running.
Furthermore, the object is also solved through a wind power plant with a gear box, which is designed as described above. In order to avoid repetitions, reference is made expressly to the above explanations.
Furthermore, the object is solved through the use of a work instrument in a gear box housing of a gear box, in particular planetary gear box, of a wind power plant, wherein at least one guiding means or guide tube is provided for the work instrument inside the gear box or respectively inside the gear box housing, wherein the gear box is designed as described in detail above We also expressly refer to the above explanations in order to avoid repetitions.
Furthermore, it is advantageous in one embodiment if the work instrument is designed as an inspection device, in particular an endoscope, and/or as a measurement device, in particular a sensor, more preferably as an infrared sensor or the like, and/or as a tool, in particular a processing tool, in order to perform corresponding measures or maintenance work inside the gear box at the predetermined locations.
Depending on the alignment and design or respectively arrangement of the guiding means inside the gear box, rigid or flexible endoscopes can be used within the scope of the invention. The endoscopes provided for this thereby transfer the image information from the inside of the gear box to a screen or the like and/or save the captured image data as individual images, images series or videos on a data medium.
Furthermore, it is possible in a further embodiment to use the guiding means as holders or as a holding device for optics permanently installed or arranged inside the gear box as the optical device of an endoscope. In the case of this type of design, for example a light conductor of an endoscope and/or a light source of an endoscope are installed or respectively arranged inside the gear box as the optical unit and remain there. In the case of maintenance of the gear box using an endoscope designed inside the gear box, further components of the endoscope are connected with the optics or respectively optical device or unit of the endoscope already installed inside the gear box in order to provide a complete endoscope for use, which is made up of the removable components and the optics or respectively optical device working together with the components.
Further characteristics of the invention will become apparent from the description of the embodiments according to the invention together with the claims and the included drawings. Embodiments according to the invention can fulfill individual characteristics or a combination of several characteristics.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described below in an exemplary manner, without restricting the general intent of the invention, based on exemplary embodiments in reference to the drawings, whereby we expressly refer to the schematic drawings with regard to the disclosure of all details according to the invention that are not explained in greater detail in the text. The drawings show in:
FIG. 1 a schematic representation of a wind power plant;
FIG. 2 a schematic cross-sectional view of a nacelle of a wind power plant and
FIG. 3 a schematic cross-section of a gear box or respectively planetary gear box of a wind power plant according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
In the following figures, the same or similar types of elements or respectively corresponding parts are provided with the same reference numbers in order to prevent the item from needing to be reintroduced.
FIG. 1 shows a schematic representation of a wind power plant 10 . The wind power plant 10 has a tower 11 and a rotor 12 , which comprises three rotor blades 14 , which are attached to a rotor hub 13 . When there is wind, the rotor 12 turns in the known manner. Power from a generator connected to the rotor 12 or respectively to the rotor hub 13 can hereby be generated in a machine cabin (see FIG. 2 ) arranged on the tower 11 and behind the rotor 12 and is supplied to a consumer network.
FIG. 2 shows a schematic cross-sectional view of a machine cabin 15 or respectively a nacelle arranged on the tower 11 of the wind power plant 10 . In the rotor-side area of the machine cabin 15 , a rotor shaft 16 is mounted in two bearing supports 17 , 18 on a slightly tilted machine frame 19 . The rotor shaft 16 projects towards the rotor side out of the machine cabin 15 and has a rotor flange 21 on the outside, on which the rotor 12 or respectively the rotor hub 13 of a rotor is fastened (see FIG. 1 ).
The side of the rotor shaft 16 facing away from the rotor 12 is connected with a multi-stage gear box 22 in the machine cabin 15 , wherein a locking device 23 is provided between the bearing bracket 18 and the inlet side of the gear box 22 so that the rotor 12 can be or is locked during the standstill for maintenance work on the wind power plant 10 .
The multi-stage gear box 22 consists of two planetary stages 24 . 1 , 24 . 2 arranged behind each other, which are in mechanical operative connection with each other. Moreover, the second planetary gear box stage 24 . 2 is in operative connection with a rear spur wheel stage 25 of the gear box 22 .
Through the multi-stage gear box 22 , the low rotational speed of the rotor shaft 16 over several stages is converted into a high speed of an output shaft, which drives a generator 28 via a coupling 27 . Within the scope of the invention, it is possible that the multi-stage gear box 22 can also have a planetary stage and two spur wheel stages or any another combinations of stages.
A rotor brake 26 as well as the coupling or respectively generator coupling 27 are arranged on the generator-side or respectively the side of a drive shaft of the spur wheel stage 25 facing away from the rotor. The coupling 27 is thereby connected with the generator shaft. A slip ring unit 29 for the blade adjustment of the rotor blades 14 ( FIG. 1 ) is arranged below the rotor brake 26 . The slip ring unit 29 forms the power supply device for the rotor hub 13 ( FIG. 1 ) together with a cable tube running through the gear box 22 into the rotor shaft 26 .
A schematic cross-section through a three-stage gear box 122 of a wind power plant is shown in FIG. 3 , wherein the gear box 122 has a planetary stage as the first gear box stage and two spur wheel stages as the second and third gear box stages. The gear box 122 has a housing 125 , in which the three gear box stages are arranged.
A shaft end for receiving the rotor shaft or respectively a planet carrier shaft 130 with a planet carrier 131 is arranged towards the rotor side or respectively towards the rotor-shaft side, wherein the planet carrier 131 is mounted in a rotatable manner inside the gear box by means of a front bearing 132 and a rear bearing 133 . The planet carrier shaft 130 has a collet 134 towards the rotor shaft, which is connected with the rotor shaft.
Several planet gears 140 are arranged on the planet carrier 131 , wherein a cross-section of a planet gear 140 is shown in FIG. 3 only for reasons of presentability. The planet gear 140 is arranged above a planetary bolt 141 arranged between the planet carrier 131 and the planet gear 140 , wherein two bearings 142 , 143 are arranged between the planetary bolts 141 and the planet gear 140 surrounding it so that the planet gear 140 is mounted in a rotatable manner around the planetary bolt 141 .
The planet gear 140 has a toothing 145 on its outside, which engages in a toothing 151 of a hollow wheel 150 surrounding the planet gears 140 . The fixed hollow wheel 150 has the toothing 151 on the inside so that, through rotation of the planet carrier 131 , the planet gears 140 arranged on it also rotate and the gear teeth 145 of the planet gears 140 engage in the toothing 151 of the housing-fixed hollow wheel 150 .
A sun wheel 160 , which is arranged on the sun wheel shaft 161 , is arranged in the inside area of the planet carrier 140 . The sun wheel 160 has a toothing 162 on its outside, which engages in the toothing 145 of the planet gears 140 . Under rotation of the planet carrier 130 , the sun wheel 160 is driven in a rotating manner by means of the rotating planet gears.
On the end of the sun shaft 161 facing away from the sun wheel 160 , a spur wheel 170 with an external toothing 171 is arranged on the sun wheel 161 . The sun shaft 161 is mounted in a rotatable manner on the outer end by means of a bearing 163 .
The toothing 171 of the spur wheel 170 is in contact with a pinion 173 , which is arranged or respectively designed on an intermediate shaft 174 . The intermediate shaft 174 is mounted in a rotatable manner by means of two exterior bearings 175 , 176 .
Furthermore, a spur wheel 180 is arranged on the intermediate shaft 174 , which is designed with its exterior toothing in a pinion 181 on a rotatable output shaft 185 . The output shaft 185 is connected on the output side with the generator of the wind power plant.
Moreover, according to the invention, several empty tubes 201 , 202 are arranged inside the housing 125 , into which work instruments, such as an endoscope, are inserted into the empty tubes 201 , 202 from outside or respectively, externally after removal of an inspection cover 126 on the top side of the gear box or respectively of the gear box housing 125 .
The empty tube 201 is arranged fixed inside the gear box 122 by means of holders 211 , 212 , 213 . The empty tube 201 comprises straight tube sections and bent tube sections so that the empty tube 201 is designed in a J-shaped or respectively U-shaped manner inside the gear box, whereby the area of the sun wheel shaft 161 between the spur wheel 170 and the bearing 163 of the sun wheel shaft 161 can be examined after insertion of an endoscope into the empty tube 201 . Through use of the empty tube 201 , the inspection work can be carried out without the dismantling of further inspection covers or bearing covers of the gear box 122 or respectively of the gear box housing 125 since the relocation or respectively arrangement of the empty tube 201 takes place from a central location, e.g. on the top side of the gear box 122 . The time for the inspection or respectively the positioning of an inspection tool at the corresponding location is thereby shortened due to the exact guidance of an inserted endoscope in the empty tube 201 , wherein dirt entry into the gear box is also minimized.
The second empty tube 202 is also fastened in a fixed manner via holders 221 , 222 on the inner wall of the housing, wherein the toothing area between the planetary stages 140 and the sun wheel 160 can be examined by means of an endoscope inserted into the empty tube 202 .
Moreover, it is shown in FIG. 3 that, also on a rotating component, such as the planet carrier 130 , an empty tube section 203 is arranged by means of second holders 224 , 225 , wherein under rotation of the planet carrier 130 , the inlet opening of the empty tube 203 can be brought into congruence with the lower outlet opening of the empty tube 202 so that the area behind the sun wheel 160 between the sun wheel and the planet carrier 131 can be inspected through insertion of an endoscope via the empty tube 202 and the empty tube section 203 communicating with it in the working position, if it is positioned in congruence.
Moreover, another empty tube 205 is arranged on the planet carrier 131 by means of two spacers 227 , 228 , so that the bearing 132 can be examined through insertion of an endoscope into the empty tube 205 . The empty tube 205 has an empty tube section, which projects out of the plane of projection, so that further sections of the empty tube 205 are only indicated by dashed lines in it.
Due to the fact that empty tubes are also fastened or respectively arranged on rotating components of the gear box, areas that are difficult to access within the gear box 122 are also examinable in a defined position or respectively work position through fixed empty tubes. Thus, locations in the gear box are also reached, which would be inaccessible or very difficult to access due to undercuts with fixed empty tubes.
Moreover, within the scope of the invention, it is possible that, for example, mirrors or the like are arranged at the exits of the empty tube on the outlet side so that visibility into further heavily mechanically stressed and hard-to-access areas inside the housing is also enabled using an endoscope as the work instrument and mirrors.
The empty tubes 202 , 203 , 204 and 205 inside the gear box 125 are designed such that areas that are hard to access within the gear box are quickly accessible for inspection through simple insertion of an endoscope as the work instrument into the empty tubes. Further, the guiding means 201 , 202 , 203 , 204 , 205 can include an oil scraper device 206 on the end or at the outlet of the guiding means 201 , 202 , 203 , 204 , 205 .
All named characteristics, including those taken from the drawings alone, and individual characteristics, which are disclosed in combination with other characteristics, are considered alone and in combination as important to the invention. Embodiments according to the invention can be fulfilled through individual characteristics or a combination of several characteristics.
LIST OF REFERENCE NUMBERS
10 Wind power plant
11 Tower
12 Rotor
13 Rotor hub
14 Rotor blades
15 machine cabin
16 Rotor shaft
17 Bearing support
18 Bearing support
19 Machine frame
21 Rotor flange
22 Multi-stage gear box
23 Locking device
24 . 1 First planetary stage
24 . 2 Second planetary stage
25 Spur wheel stage
26 Rotor brake
27 Coupling
28 Generator
29 Slip ring unit
122 Gear box
125 Housing
126 Inspection cover
130 Planet carrier shaft
131 Planet carrier
132 Bearing
133 Bearing
134 Collet
140 Planet gear
141 Planetary bolts
142 Bearing
143 Bearing
145 Toothing
150 Hollow wheel
151 Toothing
160 Sun wheel
161 Sun wheel shaft
162 Toothing
163 Bearing
170 Spur wheel
171 Toothing
173 Pinion
174 Intermediate shaft
175 Bearing
176 Bearing
180 Spur wheel
181 Pinion
185 Output shaft
201 Empty tube
202 Empty tube
203 Empty tube
205 Empty tube
206 Oil scraper device
211 Holder
212 Holder
213 Holder
221 Holder
222 Holder
224 Holder
225 Holder
227 Holder
228 Holder | A multi-stage gear box ( 122 ) of a wind power plant, wherein the gear box ( 122 ) includes a gear box housing ( 125 ). The gear box ( 122 ) includes at least one access opening for the insertion of a work instrument into the gear box housing ( 125 ) or respectively into the interior of the gear box housing ( 125 ) is provided on the outside of the gear box housing ( 125 ) and in that at least one guiding device ( 201, 202, 203, 204, 205 ) is provided for the work instrument inside the gear box housing ( 125 ) so that the work instrument is moveable and/or positionable within the guiding device ( 201, 202, 203, 204, 205 ). Parts of the gear box ( 122 ) in the gear box housing ( 125 ) are checked and/or worked by a work instrument inserted or arranged or arrangeable in the guiding device ( 201, 202, 203, 204, 205 ). | 5 |
FIELD OF THE INVENTION
[0001] This invention relates to hydroxamic and carboxylic acid derivatives, and to their use in medicine.
BACKGROUND OF THE INVENTION
[0002] Metalloproteinases, including matrix metalloproteinase (MMP), collagenase, gelatinase and TNFα convertase (TACE), and their modes of action, and also inhibitors thereof and their clinical effects, are described in WO-A-96/11209, WO-A-97/12902 and WO-A-97/19075, the contents of which are incorporated herein by reference. MNP inhibitors may also be useful in the inhibition of other mammalian metalloproteinases such as the ADAM or ADAM-TS families.
[0003] Compounds which have the property of inhibiting the action of metalloproteinases involved in connective tissue breakdown, such as collagenase, stromelysin and gelatinase, have been shown to inhibit the release of TNFα both in vitro and in vivo. See Gearing et al(1994), Nature 370:555-557; McGeehan etal (1994), Nature 370:558-561; GB-A-2268934; and WO-A-93/20047. All ofthese reported inhibitors contain a hydroxamic acid zinc-binding group, as do the imidazole-substituted compounds disclosed in WO-A-95/23790. Other compounds that inhibit MMP and/or TNF(X are described in WO-A-95/13289, WO-A-96/11209, WO-A-96/035687, WO-A-96/03571 1, WO-A-96/035712 and WO-A-96/035714.
SUMMARY OF THE INVENTION
[0004] The invention encompasses novel compounds of formula (I) which are inhibitors of matrix metalloproteinase, ADAM or ADAM-TS enzymes, and which are usefuil for the treatment of diseases mediated by those enzymes and/or TNFα-mediated diseases, including degenerative diseases and certain cancers.
[0005] Novel compounds according to a first aspect of the invention are represented by formula (I):
[0006] wherein
[0007] R 1 is OH or NHOH;
[0008] R 2 is H, alkyl, alkenyl, alkynyl, aryl, arylalkyl, heteroaryl, heteroarylalkyl, cycloalkyl, cycloalkylalkyl, heterocyclo or heterocycloalkyl (any of which may be optionally substituted with one or more substituents selected from R 6 , W and WR6); and
[0009] R 3 is H or alkyl;
[0010] or R 2 , R 3 and the carbon atom to which they are attached together represent a carbocyclic or heterocyclic ring (either of which may be substituted with one or more substituents selected from R 6 , W and WR 6 );
[0011] R 4 is alkyl, cycloalkyl, OR 9 , CO 2 R 4 , COR 10 , S(O) q R 10 where q is 0, 1 or 2, CONR 7 R 8 , CN or S(O) q NR 7 R 8 ; two R 4 substituents may be attached to the same carbon atom to form C(R 4 ) 2 , where each R 4 may be the same or different, and CC 4 ) 2 may represent C═O;
[0012] R 5 is alkyl, cycloalkyl, aryl, heteroaryl, heterocyclo, CF 3 , OR 9 , COR 10 , S(O) q R 10 , CO 2 R 14 , CONR 7 R 8 , S(O) q NR 7 R 8 , halogen, NR 10 OR 11 or CN, or two adjacent R 5 substituents may be combined to form a heterocyclic ring;
[0013] R 6 is OR 9 , COR 10 , CO 2 R 15 , CONR 7 R, NRLOR 1, S(O)R 10 , S(O) q NR 7 R 8 , ═O, ═NOR 10 , succinimido or the group
[0014] R 7 and R 8 , which may be the same or different, are each H, alkyl, cycloalkyl, aryl, heteroaryl, heterocyclo, arylalkyl, heterarylallyl, heterocycloalkyl or cycloalkylalkyl, or R 7 and R 1 and the nitrogen to which they are attached together represent a heterocyclic ring;
[0015] R 9 is H, alkyl, CF 3 , CHF 2 , CH 2 F, cycloalkyl, aryl, heteroaryl, heterocyclo, arylalkyl, heterarylalkyl, heterocycloalkyl or cycloalkylalkyl;
[0016] R 10 is H, alkyl, cycloalkyl, aryl, heteroaryl, heterocyclo, arylalkyl, heterarylalkyl, heterocycloalkyl or cycloalkylalkyl; and
[0017] R 11 is H, alkyl, cycloalkyl, aryl, heteroaryl, heterocyclo, arylalkyl, heterarylalkyl, heterocycloalkyl, cycloalkylalkyl, COR 12 , CONR 7 R 8 , S(O) q R 12 or S(O) q NR 7 R 8 ;
[0018] or R 10 and R 11 and the nitrogen to which they are attached together represent a heterocyclic ring;
[0019] R 12 is OR 9 or R 13 ;
[0020] R 13 is alkyl, cycloalkyl, aryl, heteroaryl, heterocyclo, arylalkyl, heterarylalkyl, heterocycloalkyl or cycloalkylalkyl;
[0021] R 14 is H, alkyl or cycloalkyl;
[0022] R 15 is H, alkyl or cycloalkyl, arylalkyl or heteroarylalkyl;
[0023] R 16 is H or alkyl;
[0024] A is aryl or heteroaryl, provided that when A is phenyl, R 3 is H;
[0025] W is alkyl, cycloalkyl, cycloalkylalkyl, aryl, arylalkyl, heteroaryl, heteroarylalkyl, heterocyclo or heterocycloalkyl;
[0026] each k and m is independently 0, 1, 2 or 3;
[0027] n is 0, 1 or 2; and
[0028] p is 0, 1 or 2;
[0029] or a salt, solvate, hydrate, N-oxide, protected amino, protected carboxy or protected hydroxamic acid derivative thereof
DESCRIPTION OF THE INVENTION
[0030] It will be appreciated that the compounds according to the invention can contain one or more asymmetrically substituted carbon atoms. The presence of one or more of these asymmetric centres in a compound offormula (I) can give rise to stereoisomers, and in each case the invention is to be understood to extend to all such stereoisomers, including enantiomers and diastereomers, and mixtures including racemic mixtures thereof
[0031] It will further be appreciated that the compounds according to the invention may contain an oxime. This oxime can give rise to geometrical isomers, and in each case the invention is to be understood to extend to all such isomers and mixtures thereof
[0032] As used in this specification, alone or in combination, the term “alkyl” refers to straight or branched chain alkyl moiety having from one to six carbon atoms, including for example, methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, pentyl, hexyl and the like.
[0033] The term “alkenyl” refers to a straight or branched chain alkyl moiety having two to six carbon atoms and having in addition one double bond, of either E or Z stereochemistry where applicable. The term alkenyl includes for example, vinyl, 1-propenyl, 1- and 2- butenyl, 2- methyl-2-propenyl and the like.
[0034] The term “alkynyl” refers to a straight or branched chain alkyl moiety having two to six carbon atoms and having in addition one triple bond. The term altynyl includes for example, ethynyl, 1-propynyl, 1- and 2- butynyl, 1- methyl-2-butynyl and the like.
[0035] Cycloalkyl or carbocyclic ring refers to a non-aromatic cyclic or multicyclic, saturated or partially saturated ring system having from three to ten carbon atoms which may be optionally benzofused at any available position. Thus cycloalkyl includes, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, tetrahydronaphthyl, bicyclo[2.2. 1]heptanyl, bicyclo[2.2. I]heptenyl, cyclopentenyl, indanyl and the like.
[0036] Heterocyclo or heterocyclic ring refers to a 3 to 10 membered saturated or partially saturated monocyclic or saturated or partially saturated multicyclic hydrocarbon ring system in which one or more of the atoms in the ring system is an element other than carbon, chosen from amongst nitrogen, oxygen or sulphur (or oxidised versions thereof, such as N-oxide, sulphoxide, sulphone). Examples include azetidinyl, pyrrolidinyl, 1 5 tetrahydrofuryl, piperidinyl, quinuclidinyl, tetrahydropyranyl, morpholinyl, thiomorpholinyl, piperazinyl, N-alkyl-piperazinyl, homopiperazinyl, oxazolidinyl, imidazolidinyl, thiazolidinyl, pyrazolidinyl, benzodioxole, [2,3-dihydro]benzofuryl, [3,4-dihydro]benzopyranyl, 1,2,3,4 tetrahydroquinolinyl, 1,2,3,4 tetrahydroisoquinolinyl, 8-oxabicyclo[3.2.1]octane, indolinyl, isoindolinyl, and the like.
[0037] Aryl indicates carbocyclic radicals containing 6 to 10 carbon atoms and containing either a single ring or two condensed rings. Thus aryl includes, for example, phenyl and naphthyl.
[0038] Heteroaryl refers to a 5 to 10 membered aromatic monocyclic or multicyclic hydrocarbon ring system in which one or more of the atoms in the ring system is an element other than carbon, chosen from amongst nitrogen, oxygen or sulphur (or oxidised versions thereof, such as N-oxide). In general, the heteroaryl groups may be for example monocyclic or bicyclic fused ring heteroaryl groups. Monocyclic heteroaryl groups include, for example, five- or six-membered heteroaryl groups containing one, two, three or four heteroatoms selected from oxygen, sulphur or nitrogen atoms. Bicyclic heteroaryl groups include for example eight- to ten-membered fused-ring heteroaryl groups containing one, two or more heteroatoms selected from oxygen, sulphur or nitrogen atoms.
[0039] The term heteroaryl includes, for example, pyrrolyl, furyl, thienyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyrazolyl, 1,2,3-triazolyl, 1,2,4-triazolyl, 1,2,3-oxadiazolyl, 1,2,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl, 1,2,5-thiadiazolyl, 1,3,4- thiadiazolyl, pyridyl, pyridyl-N-oxide, pyrimidinyl, pyridazinyl, pyrazinyl, 1,3,5-triazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, benzofuryl, benzothienyl, benzotriazolyl, indolyl, isoindolyl, benzimidazolyl, imidazo[1,2-a]pyridyl, benzothiazolyl, benzoxazolyl, benzisoxazolyl, benzopyranyl, quinazolinyl, quinoxalinyl, naphthyridinyl, pyrido[3,4-b]pyridyl, pyrido[3,2-b]pyridyl, pyrido[4,3-b]-pyridyl, quinolinyl, isoquinolinyl, phthalazinyl, tetrazolyl and the like.
[0040] Arylalkyl includes an aryl-alkyl- group wherein the aryl and alkyl are as described herein. Heteroarylalkyl includes a heteroaryl-alkyl- group, cycloalkylalkyl includes a cycloalkyl-alkyl- group and heterocycloalkyl includes a heterocyclo-alkyl- group, wherein all groups are as defined above.
[0041] The term “halogen” includes fluorine, chlorine, bromine or iodine.
[0042] The term “benzofused” means the addition of a benzene ring sharing a common bond with the defined ring system.
[0043] The term “optionally substituted” means optionally substituted by one or more of the groups specified, at any available position or positions.
[0044] The terms “protected amino”, “protected carboxy” and “protected hydroxamic acid” mean amino, carboxy and hydroxamic acid groups which can be protected in a manner familiar to those skilled in the art. For example, an amino group can be protected by a benzyloxycarbonyl, tert-butoxycarbonyl, acetyl or like group, or may be in the form of a phthalimido or like group. A carboxyl group can be protected in the form of a readily-cleavable ester such as the methyl, ethyl, benzyl or tert-butyl ester. A hydroxamic acid may be protected as either N or O-substituted derivatives, such as O-benzyl or O-tert-butyldimethylsilyl.
[0045] Salts of compounds of formula (I) or formula (II) include pharmaceutically-acceptable salts, for example acid addition salts derived from inorganic or organic acids, such as hydrochlorides, hydrobromides, p-toluenesulphonates, phosphates, sulphates, perchlorates, acetates, trifluoroacetates, propionates, citrates, malonates, succinates, lactates, oxalates, tartrates and benzoates.
[0046] Salts may also be formed with bases. Such salts include salts derived from inorganic or organic bases, for example alkali metal salts such as magnesium or calcium salts, and organic amine salts such as morpholine, piperidine, dimethylamine or diethylarnine salts.
[0047] When the “protected carboxy” group in compounds ofthe invention is an esterified carboxyl group, it may be a metabolically-labile ester of formula CO 2 R where R may be an ethyl, benzyl, phenethyl, phenylpropyl, (x or O-naphthyl, 2,4-dimethylphenyl, 4-tert-butylphenyl, 2,2,2-trifluoroethyl, 1-(benzyloxy)benzyl, 1-(benzyloxy)ethyl, 2-methyl-1-propionyloxypropyl, 2,4,6-trimethylbenzyloxymethyl or pivaloylmethyl group.
[0048] Preferred compounds of the invention are those wherein any one or more of the following may apply:
[0049] One group of compounds of the invention has the formula (I) in which R 1 is NHOH.
[0050] In one preferred group of compounds of formula (I) R 2 is in particular isopropyl or isobutyl, especially isopropyl.
[0051] Another preferred group of compounds of formula (I) is where R 2 is a substituted alkyl group, especially substituted methyl, ethyl or propyl. R 2 in compounds of this type is preferably substituted by R 6 , where R 6 is especially CO 2 R 15 , in particular CO 2 H, CONR 7 R 8 , NR 10 OR 11 , succinimido or the group
[0052] In compounds of this type CONR 7 R 8 is in particular CON(H) 2 , CON(H)alkyl, CON(alkyl) 2 or R 7 and R 1 are attached together to form a heterocyclic ring. NR 10 R 11 in compounds ofthis type is especially N(H)COR 12 or N(alkyl)COR 12 , particularly preferred is where R 12 is alkyl. Each R 16 in compounds of the invention is in particular methyl.
[0053] A further preferred group of compounds ofthe invention has the formula (I) where R 2 is an optionally substituted cycloalkyl or heterocyclo group, especially an optionally substituted heterocyclo group. In compounds of this type R 2 is in particular azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, tetrahydrofuryl or tetrahydropyranyl, especially optionally substituted piperidinyl. When substituted compounds of this type may in particular be substituted by R 6 , especially where R 6 is CO 2 R 15 . R 15 may in particular be arylalkyl or heteroarylalkyl, preferably arylalkyl, especially benzyl.
[0054] R 3 in compounds of the invention may in particular be a hydrogen atom.
[0055] One group of compounds of the invention has the formula (I) in which R 2 , R 3 and the carbon atom to which they are attached together represent an optionally substituted carbocylic or heterocyclic ring. Especially preferred compounds in this group are those where CR 2 R 3 is a cycloalkyl or a heterocyclic ring, in particular, C 3-7 cycloalkyl groups, especially, cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl groups, and C 3-7 heterocyclo groups, especially, azetidinyl, pyrrolidinyl, tetrahydrofuryl, tetrahydropyranyl, piperidinyl and piperazinyl. In compounds of this type CR 2 R 3 is in particular cyclobutyl, cyclopentyl, cyclohexyl or tetrahydropyranyl.
[0056] Especially preferred is where p=1 and n=1.
[0057] In compounds of the invention k is preferably 0.
[0058] R 5 , when present may in particular be C 3-7 cycloaLkyl, aryl, monocyclic heteroaryl, C 3-7 heterocyclo, CF 3 , OR 9 , CONR 7 R 8 , F, Cl, Br, I or CN. Especially preferred is where Rs is cyclobutyl, cyclopentyl, cyclohexyl, phenyl, CF 3 , OCH 3 , OCF 3 , OCHF 2 , OCH 2 F, CONH 2 , CONHCH 3 , CON(CH 3 ) 2 , CN, F, Cl, Br or I. In compounds where R 5 is present m is preferably 1 or 2.
[0059] One particular group of compounds of interest is represented by the formula (Ia):
[0060] wherein R 1 , R 2 , R 4 , R 5 , k and m, n and p are as previously described. In compounds of formula (Ia) R 3 is a hydrogen atom.
[0061] Another group of compounds has the formula (I) wherein A is in particular pyrrolyl, furyl, thienyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyrazolyl, 1,2,3-triazolyl, 1,2,3-oxadiazolyl, 1,2,5-oxadiazolyl 1,2,3-thiadiazolyl, 1,2,5-thiadiazolyl, pyridyl, pyrimidinyl, pyridazinyl, pyrazinyl, 1,2,4-triazinyl or 1,2,3-triazinyl, especially thiazolyl.
[0062] Particularly preferred compounds of the invention are:
[0063] 1-[2-(3,4-Dihydro- H-isoquinoline-2-sulfonyl)-1-hydroxycarbamoyl-ethyl]-piperidine-1-carboxylic acid benzyl ester;
[0064] 2-(6-Cyclohexyl-3 ,4-dihydro- 1H-isoquinoline-2-sulfonylmethyl)-N-hydroxy-3-methyl-butyramide;
[0065] N-Hydroxy-3-methyl-2-(6-phenyl-3,4-dihydro-1H-isoquinoline-2-sulfonylmethyl)-butyramide;
[0066] 2-(6,7-Dimethoxy-3,4-dihydro-IH-isoquinoline-2-sulfonylmethyl)-N-hydroxy-3-methyl-butyramide;
[0067] N-Hydroxy-3-methyl-2-(2-phenyl-6,7-dihydro-4H-thiazolo[5,4-c]pyridine-5-sulfonylmethyl)-butyramride;
[0068] and the salts, solvates, hydrates, N-oxides, protected amino, protected carboxy and protected hydroxamic acid derivatives thereof.
[0069] Compounds of the general formula (I) may be prepared by any suitable method known in the art and/or by the following processes.
[0070] It will be appreciated that, where a particular stereoisomer of formula (1) is required, the synthetic processes described herein may be used with the appropriate homochiral starting material and/or isomers maybe resolved from mixtures using conventional separation techniques (e.g. HPLC).
[0071] The compounds according to the invention may be prepared by the following process. In the description and formulae below, the various groups R and other variables are as defined above, except where otherwise indicated. It will be appreciated that functional groups, such as amino, hydroxyl or carboxyl groups, present in the various compounds described below, and which it is desired to retain, may need to be in protected form before any reaction is initiated. In such instances, removal of the protecting group may be the final step in a particular reaction. Suitable protecting groups for such functionality will be apparent to those skilled in the art. For specific details see Greene et al, “Protective Groups in Organic Synthesis”, Wiley Interscience (1999).
[0072] Thus, for example, compounds of the invention may be prepared by the following general route:
[0073] Compounds of formula (IV), where W is for example an alkoxy group, such as methoxy, ethoxy or tert-butoxy or a chiral auxiliary, for example, 4-(R)-benzyloxazolidin-2-one, may be prepared by methods well known in the literature, for example, by reaction of a sulfonyl chloride (II) with an amine (III) in the presence of an amine base, such as triethylamine in a halogenated solvent, such as dichloromethane at room temperature.
[0074] Compounds of general formula (II) are either known or may be made by one skilled in the art using methods known in the literature, see for example WO-A-99/24399, or as described in the examples herein after. Compounds of general formula (III) are available commercially or they be made using methods known in the literature or by any method known to those skilled in the art. For example, an amine of general formula (III) may be prepared by selective hydrogenation of a heteroaryl group, such as isoquinoline using for example a platinum catalyst under acidic conditions. Appropriate conditions may be platinum (IV) oxide in the presence of concentrated hydrochloric acid in ethanol under a pressure of 690 kPa. Alternatively, an amine of formula (III) where A is a heteroaryl group such as thiazolyl or oxazolyl may be prepared by formation of such a heteroaryl group on a suitably functionalised amine ring such as N-tert-butoxycarbonyl-protected piperidin-4-one using well known methods. For example, the piperidinone (V) may be a-halogenated using standard conditions, such as reaction of the ketone with trimethylsilyl chloride and an amine base such as triethylamine in N,N-dimnethylformamide at 70° C., followed by c-halogenation using, for example, N,N-bromosuccinimide in a suitable solvent such as acetonitrile. The α-bromoketone (VI) may then be reacted with a suitable amide or thioamide, such as thiobenzamide in conditions such as N,N-dimethylformamide at 80° C., to form the desired heteroaryl ring, as illustrated in the scheme below:
[0075] Carboxylic acids of general formula (I) may be prepared by deprotection of a suitably protected carboxylic acid of formula (IV). For example, where W is an alkoxy group, such as ethoxy, a base such as aqueous lithium hydroxide may be used, alternatively trifluoroacetic acid may be used when W is a tert-butyl group or in the case of a chiral auxiliary such as 4-(R)-benzyl-oxazolidin-2-one, lithium hydroxide/hydrogen peroxide may be used. Appropriate solvent and temperature conditions such as those described in the examples herein after may be used.
[0076] Compounds of formula (I) may also be prepared by interconversion of other compounds of formula (I). Thus, for example, hydroxamic acids of general formula (1) may be prepared using conditions well known in the literature. For example, treatment of acids of formula (I) with oxalyl chloride in an inert solvent (such as dichloromethane) gives an intermediate acid chloride, which may or may not be isolated, but which in turn is reacted with hydroxylamine at a suitable temperature such as room temperature to give the desired hydroxamic acids (I). Alternatively an acid of formula (I) maybe activated in situ using for example a diimide such as 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, advantageously in the presence of a catalyst such as a N-hydroxy compound, e.g. N-hydroxybenzotriazole using suitable conditions, e.g. in N,N-dimethylformamide at -15° C., prior to the subsequent addition of a suitably protected hydroxylamine such as tert-butyldimethyl silyl hydroxylamine and warming to ambient temperature. The protecting group maybe removed using appropriate conditions, such as water or tetrabutylanunonium fluoride and acetic acid in tetrahydrofuran at 0C, to yield the desired hydroxamic acids of formula (I).
[0077] Similarly, intermediates of any appropriate formula may be prepared by the interconversion of other compounds of the same formula.
[0078] Any mixtures of final products or intermediates obtained can be separated on the basis of the physico-chemical differences of the constituents, in known manner, into the pure final products or intermediates, for example by chromatography, distillation, fractional crystallization, or by formation of a salt if appropriate or possible under the circumstances.
[0079] The compounds according to the invention exhibit in vitro inhibiting activities with respect to the stromelysin, collagenase, gelatinase, ADAM or ADAM-TS enzymes. 20 Compounds according to the invention may also exhibit in vitro inhibition of membrane-shedding events known to be mediated by metalloproteinases, for example, α-APP, ACE, TGF-α, TNF-α, Fas ligand, selectins, TNFR-I, TNFR-II, CD30, Il-6R, CD43, CD44, CD16-I, CD16-II, Folate receptor, CD23, or IL-1RII.
[0080] The activity and selectivity of the compounds may be determined by use of the 25 appropriate enzyme inhibition test, for example as described in Examples A-M of WO-A-98/05635, bythe assay for the inhibition of CD23 shedding described in WO-A-99/24399, or by the assay of TNF RI shedding described in WO-A-00/56704.
[0081] This invention also relates to a method of treatment for patients (including man and/or mammalian animals raised in the dairy, meat or fur industries or as pets) suffering from disorders or diseases which can be attributed to metalloproteinases.
[0082] Accordingly, the compounds of formula (I) can be used among other things in the treatment of osteoarthritis and rheumatoid arthritis, and in diseases and indications resulting from the over-expression of these matrix metalloproteinases such as found in certain metastatic tumour cell lines.
[0083] As mentioned above, compounds of formula (I) are useful in human or veterinary medicine since they are active as inhibitors of TNF and MMPs. Accordingly in another aspect, this invention concerns:
[0084] a method of management (by which is meant treatment or prophylaxis) of disease or conditions mediated by TNF, MMPs, ADAM or ADAM-TS enzymes, in mammals, in particular in humans, which method comprises administering to the mammal an effective, amount of a compound offormula (I) above, or a pharmaceutically acceptable salt thereof; and
[0085] a compound of formula (I) for use in human or veterinary medicine, particularly in the management (by which is meant treatment or prophylaxis) of diseases or conditions mediated by TNF, MMPs, ADAM or ADAM-TS enzymes; and
[0086] the use of a compound of formula (I) in the preparation of an agent for the management (by which is meant treatment or prophylaxis) of diseases or conditions mediated by TNF, MMPs, ADAM or ADAM-TS enzymes.
[0087] The disease or conditions referred to above include inflammatory diseases, autoimmune diseases, cancer, cardiovascular diseases and diseases involving tissue breakdown. Appropriate diseases include rheumatoid arthritis, osteoarthritis, osteoporosis, neurodegeneration, Alzheimer's disease, stroke, vasculitis, Crohn's disease, ulcerative colitis, multiple sclerosis, periodontitis, gingivitis and those involving tissue breakdown such as bone resorption, haemorrhage, coagulation, acute phase response, cachexia and anorexia, acute infections, bacterial infections, HIV infections, fever, shock states, graft versus host reactions, dermatological conditions, surgical wound healing, psoriasis, atopic dermatitis, epidermolysis bullosa, tumour growth, angiogenesis and invasion by secondary metastases, ophthalmological disease, retinopathy, corneal ulceration, reperfusion injury, migraine, meningitis, asthma, rhinitis, allergic conjunctivitis, eczema, anaphylaxis, restenosis, congestive heart failure, endometriosis, atherosclerosis, endosclerosis, aspirin-independent antα-thrombosis, systemic lupus erythematosus and solid organ transplant.
[0088] Compounds of formula (I) may also be useful in the treatment of pelvic inflammatory disease (PID), age-related macular degeneration and cancer-induced bone resorption. Further, they can be used in the treatment of lung diseases, e.g. selected from cystic fibrosis, adult respiratory distress syndrome -(ARDS), emphysema, bronchitis obliterans-organising pneumonia (BOOP), idiopathic pulmonary fibrosis (PIF), diffuse alveolar damage, pulmonary Langerhan's cell granulamatosis, pulmonary lymphangioleiomyomatosis (LAM) and chronic obstructive pulmonary disease (COPD).
[0089] Compounds of the invention are particularly of use in the treatment of inflammatory diseases, autoimmune diseases and cancer. Thus, for example, the compounds may be used in the treatment (including prophylaxis) of graft versus host reactions, psoriasis, atopic dermatitis, rhinitis, eczema, systemic lupus erythematosus, solid organtransplant, cystic fibrosis, rheumatoid arthritis, osteoarthritis, osteoporosis, Crohn's Disease, ulcerative colitis, multiple sclerosis, periodontitis, bone resorption, bacterial infections, epidermolysis bullosa, tumour growth, angiogenesis, ophthalmological disease, retinopathy, asthma, emphysema, bronchitis, and chronic obstructive pulmonary disease (COPD).
[0090] For the treatment of all diseases and disorders previously indicated, the compounds of formula (I) may be administered orally, topically, parenterally, by inhalation spray or rectally in dosage unit formulations containing non-toxic pharmaceutically acceptable carriers, adjuvants and vehicles. The term parenteral as used herein includes subcutaneous injections, intravenous, intramuscular, intrasternal injection orinfusiontechniques. Ocular injection, such as intravitreal, subtenons, subconjunctival, periocular and retrobulbar may also be used, as well as intraocular slow release devices and implants. In addition to the treatment ofwarm-blooded animals such as mice, rats, horses, cattle, sheep, dogs, cats etc, the compounds of the invention are effective in the treatment of humans.
[0091] The pharmaceutical composition containing the active ingredient may be in a form suitable for oral use, for example, as tablets, troches, lozenges, aqueous or oily suspensions, dispersible powders or granules, emulsions, hard or soft capsules, or syrups or elixirs. Compositions intended for oral use may be prepared according to any method known to the art for the manufacture of pharmaceutical compositions and such compositions may contain one or more agents selected from sweetening agents, flavouring agents, colouring agents and preserving agents in order to provide pharmaceutically elegant and palatable preparations. Tablets contain the active ingredient in admixture with non-toxic pharmaceutically acceptable excipients which are suitable for the manufacture oftablets. These excipients may be for example, inert diluents, such as calcium carbonate, sodium carbonate, lactose, calcium phosphate or sodium phosphate; granulating and disintegrating agents, for example corn starch, or alginic acid; binding agents, for example starch, gelatin or acacia, and lubricating agents, for example magnesium stearate, stearic acid or talc. The tablets may be uncoated or they may be coated by known techniques to delay disintegration and absorption in the gastointestinal tract and thereby provide a sustained action over a longer period. For example, a time delay material such as glyceryl monostearate or glyceryl distearate may be employed. They may also be coated by the techniques described in the U.S. Pat. No. 4256108, U.S. Pat. No. 4166452 and U.S. Pat. No. 4265874, to form osmotic therapeutic tablets for controlled release.
[0092] Formulations for oral use may also be presented as hard gelatin capsules where in the active ingredient is mixed with an inert solid diluent, for example calcium carbonate, calcium phosphate or kaolin, or as soft gelatin capsules wherein the active ingredient is mixed with water or an oil medium, for example peanut oil, liquid paraffin or olive oil.
[0093] Aqueous suspensions contain the active materials in admixture with excipients suitable for the manufacture of aqueous suspensions. Such excipients are suspending agents, for example sodium carboxymethylcellulose, methylcellulose, hydroxypropylmethylcellulose, sodium alginate polyvinyl-pyrrolidone, gum tragacanth and gum acacia; dispersing or wetting agents may be a naturally occurring phosphatide, for example lecithin, or condensation products of an alkylene oxide with fatty acids, for example polyoxyethylene stearate, or condensation products of ethylene oxide with long chain aliphatic alcohols, for example heptadecaethyleneoxycetanol, or condensation products of ethylene oxide with partial esters derived from fatty acids and a hexitol such a polyoxyethylene with partial esters derived from fatty acids and hexitol anhydrides, for example polyoxyethylene sorbitan monooleate. The aqueous suspensions may also contain one or more preservatives, for example ethyl, or n-propyl, p-hydroxybenzoate, one or more colouring agents, one or more flavouring agents, and one or more sweetening agents, such as sucrose or saccharin.
[0094] Oily suspensions may be formulated by suspending the active ingredient in a vegetable oil, for example arachis oil, olive oil, sesame oil or coconut oil, or in a mineral oil such as liquid paraffin. The oily suspensions may contain a thickening agent, for example beeswax, hard paraffin or cetyl alcohol. Sweetening agents such as those set forth above, and flavouring agents may be added to provide a palatable oral preparation. These compositions may be preserved by the addition of an antα-oxidant such as ascorbic acid.
[0095] Dispersible powders and granules suitable for preparation of an aqueous suspension by the addition of water provide the active ingredient in admixture with a dispersing or wetting agent, suspending agent and one or more preservatives. Suitable dispersing or wetting agents and suspending agents are exemplified, for example sweetening, flavouring and colouring agents may also be present.
[0096] The pharmaceutical compositions ofthe invention may also be in the form of oil-in-water emulsions. The oily phase may be a vegetable oil, for example olive oil or arachis oil, or a mineral oil, for example liquid paraffin or mixtures of these. Suitable emulsifying agents may be naturally occurring gums, for example gum acacia or gum tragacanth, naturally occurring phosphatides, for example soya bean, lecithin, and esters or partial esters derived from fatty acids and hexitol anhydrides, for example sorbitan monooleate and condensation products of the said partial esters with ethylene oxide, for example polyoxyethylene sorbitan monooleate. The emulsions may also contain sweetening and flavouring agents.
[0097] Syrups and elixirs may be formulated with sweetening agents, for example glycerol, propylene glycol, sorbitol or sucrose. Such formulations may also contain a demulcent, a preservative and flavouring and colouring agents. The pharmaceutical compositions may be in the form of a sterile injectable aqueous or oleagenous suspension. This suspension may be formulated according to the known art using those suitable dispersing or wetting agents and suspending agents which have been mentioned above. The sterile injectable preparation may also be in a sterile injectable solution or suspension in a non-toxic parenterally-acceptable diluent or solvent, for example as a solution in 1,3-butanediol. Among the acceptable vehicles and solvents that may be employed are water, Ringer's solution and isotonic sodium chloride solution. In addition, sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose any bland fixed oil may be employed including synthetic mono- or diglycerides. In addition, fatty acids such as oleic acid find use in the preparation of injectables.
[0098] A compound ofthe invention may also be administered in the form of suppositories for rectal administration of the drug. These compositions can be prepared by mixing the drug with a suitable non-irritating excipient which is solid at ordinary temperatures but liquid at the rectal temperature and will therefore melt in the rectum to release the drug. Such materials are cocoa butter and polyethylene glycols.
[0099] For topical use, creams, ointments, jellies, solutions or suspensions, etc, containing a compound of the invention are employed. For the purposes ofthis specification, topical application includes mouthwashes and gargles.
[0100] For topical ocular administration, pharmaceutically acceptable solutions, suspensions or gels containing the compounds of formula (I) may be used. Solutions and suspensions may also be adapted for intra-vitreal or intra-cameral use.
[0101] Dosage levels of the order of from about 0.05 mg to about 140 mg per kilogram of body weight per day are useful in the treatment of the above-indicated conditions (about 2.5 mg to about 7 g per patient per day). For example, inflammation may be effectively treated by the administration of from about 0.01 to 50 mg ofthe compound per kilogram of body weight per day (about 0.5 mg to about 3.5 g per patient per day).
[0102] The amount of active ingredient that may be combined with the carrier materials to produce a single dosage form will vary depending upon the host treated and the particular mode of administration. For example, a formulation intended for the oral administration of humans may vary from about 5 to about 95% of the total composition. Dosage unit forms will generally contain between from about 1 mg to about 500 mg of active ingredient.
[0103] It will be understood, however, that the specific dose level for any particular patient will depend upon a variety of factors including the activity of the specific compound employed, the age, body weight, general health, sex, diet time of administration, route of administration, rate of excretion, drug combination and the severity of the particular disease undergoing therapy.
[0104] The following Examples illustrate the invention.
[0105] The following abbreviations are used:
Boc-tert-butoxy carbonyl; DCM-dichloromethane DMF-N,N-dimethylformamide EtOAc-ethyl acetate MeOH-methanol NBS-N-bromosuccinimide TFA-trifluoroacetic acid
[0106] Intermediate 1 6-Cyclohexyl-1,2,3,4tetrahydro-isoquinoline
[0107] Platinum (IV) oxide (30mg), then 12M hydrochloric acid (1.5ml) was added to a solution of 6-phenyl-isoquinoline (1 .52g) in ethanol (30ml). The mixture was transferred to a Parr high pressure apparatus and charged with hydrogen to a pressure of 50 psi. The reaction was stirred at room temperature for 3 h then recharged with hydrogen to 100 psi and left to stir for 16 h. The mixture was then filtered, fresh platinum catalyst and 12M hydrochloric acid added, and the Parr high pressure apparatus charged to 75 psi. The reaction was left to stir at room temperature for 16 h, after which a white crystalline solid was observed in the reaction mixture. Water was added to dissolve this solid and the mixture filtered through celite, washing with 1:1 water-methanol (3×30 ml). The methanol was removed under reduced pressure then the aqueous basified with concentrated sodium hydroxide solution and extracted with 2:1 diethyl ether-ethyl acetate (3×50 ml). The combined extracts were washed with water (2×20 ml), saturated sodium bicarbonate (20 ml) and brine (20 ml) then dried (Na 2 SO 4 ), filtered and evaporated under reduced pressure. The residue was purified by chromatography (SiO 2 , 93:6:1 dichloromethane-methanol-ammonia, then a second column with 94:5:1 dichloromethane-methanol-ammonia) to give the title compound (190 mg) as a mixture containing approximately 20% of a slightly higher running product.
[0108] R f 0.27 (94:5:1 dichloromethane-methanol-ammonia)
[0109] Intermediate 2 4 Benzenesulfonyloxy-piperidine-1-carboxylic acid benzyl ester
[0110] Triethylamine (17 ml) was added dropwise to a solution of benzyl 4-hydroxy-1-piperidinecarboxylate (28.83 g) in dichloromethane (lOOml) at 0° C. and stirred for 15 minutes. Benzenesulfonyl chloride (14 ml) was added and the reaction allowed to stir at room temperature for 48 h. The mixture was washed with water (50 ml), saturated sodium bicarbonate solution (50 ml), water (50 ml) and brine (50 ml) then dried (Na 2 SO 4 ), filtered and evaporated under reduced pressure. The residue was purified by chromatography (SiO 2 , 20% ethyl acetate in hexane to 30% ethyl acetate in hexane) to give the title compound (31.88 g, 77%) as a white crystalline solid. R f 0.62 (5% methanol in dichloromethane)
[0111] Intermediate 3 2-(1-Benzyloxycarbonyl-piperidin-4 yl)-malonic acid
[0112] Sodium metal (3.2 g) was dissolved in ethanol (50 ml) under a nitrogen atmosphere at room temperature. A solution of diethyl malonate (56.4 ml) in ethanol (50 ml) was added dropwise, followed by a solution of 4-benzenesulfonyloxy-piperidine-1-carboxylic acid benzyl ester (31.88 g) in ethanol (50 ml), also added dropwise. The mixture was heated to reflux for 16 h then the solvent was removed under reduced pressure. The residue was partitioned between water (100 ml) and diethyl ether (100 ml) and the aqueous washed with further diethyl ether (60 ml). The combined organics were washed with 10% citric acid solution (50 ml), water (50 ml) and brine (50 ml). After drying (Na 2 SO 4 ) and filtering the solvent was removed under reduced pressure to leave a yellow liquid. Half of this crude diester was taken and dissolved in methanol (150 ml) and water (50 ml). Lithium hydroxide monohydrate (18.14 g) was added slowly and the reaction left to stir at room temperature for 16 h then the methanol was removed under reduced pressure. The aqueous was washed with diethyl ether (3×40 ml), acidified to pH=3 with citric acid and extracted with ethyl acetate (2×40 ml). The combined organics were washed with water (2×40 ml) and brine (40 ml), dried (Na 2 SO 4 ), filtered and evaporated under reduced pressure to give the title compound (8.29 g, 56%) as a white crystalline solid.
[0113] R f 0.47 (5% methanol in dichloromethane)
[0114] Intermediate 4 4 (1-Carboxy-vinyl)-piperidine-1-carboxylic acid benzyl ester
[0115] 2-(1-Benzyloxycarbonyl-piperidin-4-yl)-malonic acid (18.06 g) was dissolved in tetrahydrofuran (140 ml) and morpholine (4.95 ml) followed by acetic acid (6.43 ml) was added, forming a white precipitate. Formaldehyde (4.56 g) was added, causing the precipitate to disappear, and the mixture heated to reflux for 4 h. The solvent was evaporated, diethyl ether (50 ml) added and the mixture extracted with water (3×60 ml). The aqueous was acidified to pH═3 with citric acid and extracted with diethyl ether (3×30 ml). The combined organic extracts were washed with water (40 ml) and brine (40 ml), dried (Na 2 SO 4 ), filtered and the solvent removed under reduced pressure to give the title compound (16.65 g) as a mixture containing approximately 10% of the acid starting material.
[0116] R f 0.5 (5% methanol in dichloromethane)
[0117] Intermediate 5 4-(2-Acetylsulfanyl-1-carboxy-ethyl)-piperidine-1 carboxylic acid benzyl ester
[0118] 4-(1-Carboxy-vinyl)-piperidine-1-carboxylic acid benzyl ester (15.6 g) was dissolved in thioacetic acid (lSml) and heated to reflux for 3 h. The thioacetic acid was evaporated under reduced pressure and azeotroped with 1:1 hexane-dichloromethane (4×30 ml) to give the title compound (20.32 g, 95%) as an orange oil. R f 0.28 (40% ethyl acetate in hexane)
[0119] Intermediate 6 4 (2-Acetylsulfanyl-1-tert-butoxycarbonyl-ethyl)-piperidine-1-carboxylic acid benzyl ester
[0120] Sulfuric acid (1. 1Sml) was added slowly to a solution of 4-(2-acetylsulfanyl-1-carboxy-ethyl)-piperidine-1-carboxylic acid benzyl ester (20.32 g) in dichloromethane (60 ml). The mixture was cooled in an acetone/dry ice bath and cooled isobutylene (60 ml)added. The mixture was transferred to a Parr high pressure apparatus and left to stir overnight then washed with water (30 ml), saturated sodium bicarbonate solution (30 ml) and brine (30 ml). After drying (Na 2 SO 4 ) and filtering the solvent was removed under reduced pressure and the residue purified by column chromatography (SiO 2 , 20% ethyl acetate in hexane) to give the title compound (11.22 g, 60%) as an orange oil.
[0121] R f 0.25 (20% ethyl acetate in hexane)
[0122] Intermediate 7 4 (1-tert-Butoxycarbonyl-2 hlorosulfonyl-ethyl)-piperidine-1-carboxylic acid benzyl ester
[0123] A solution of 4-(2-acetylsulfanyl-1-tert-butoxycarbonyl-ethyl)-piperidine-1-carboxylic acid benzyl ester (1.01 g) in dichloromethane (25 ml) and water (25 ml) was cooled in ice. Chlorine gas (500 mg) was bubbled through the solution over 10 minutes then the mixture was flushed with nitrogen gas. The mixture was washed with water (25 ml) and brine (25 ml), then dried (Na 2 SO 4 ), filtered and the solvent removed under reduced pressure to give the title compound (920 mg, 86%) as a colourless oil.
[0124] R f 0.48 (30% ethyl acetate in hexane)
[0125] Intermediate 8 4-[1-tert-Butoxycarbonyl-2-(3,4-dihydro-1H-isoquinoline-2-sulfonyl)-ethyl]-piperidine-1-carboxylic acid benzyl ester
[0126] 1,2,3,4- Tetrahydroisoquinoline (0. 17 ml) was dissolved in dichloromethane (40 ml) at room temperature under nitrogen. Triethylamine (0.19 ml) was added, followed by 4-(1-tert-butoxycarbonyl-2-chlorosulfonyl-ethyl)-piperidine-1-carboxylic acid benzyl ester (500 mg) as a solution in dichloromethane (1.5 ml). The reaction was left to stir for 64 h then diluted with dichloromethane (60 ml), washed with 10% citric acid solution (2×50 ml), water (2×50 ml), saturated sodium bicarbonate solution (2×50 ml) and brine (50 ml). The organic layer was then dried (MgSO 4 ), filtered and the solvent removed under reduced pressure to give the title compound (506 mg, 83%) as a yellow oil.
[0127] R f 0.44 (50% ethyl acetate in heptane)
[0128] The following compounds were prepared as above.
[0129] Intermediate 9 3-Methyl-2- (6-phenyl-3-4-dihydro- 1H-isoquinoline-2-sulfonylmethyl)-butyric acid tert-butyl ester
[0130] From 2-chlorosulfonylmethyl-3-methyl-butyric acid tert-butyl ester (293 mg) and 6-phenyl-1,2,3,4-tetrahydro-isoquinoline (206 mg) to give, after chromatography (SiO 2 , 25% diethyl ether in hexane), the title compound (340 mg, 78%) as a white solid.
[0131] R f 0.24 (25% diethyl ether in hexane)
[0132] Intermediate 10 2-(6-Cyclohexyl-3,4-dihydro-1H-isoquinoline-2-sulfonylmethyl)-3-methyl-butyric acid tert-butyl ester
[0133] From 2-chlorosulfonylmethyl-3-methyl-butyric acid tert-butyl ester ( 2 63 mg) and 6-cyclohexyl-1,2,3,4-tetrahydro-isoquinoline (190 mg) to give, after chromatography (SiO 2 , 25% diethyl ether in hexane), the title compound (230 mg, 58%) as a colourless gum.
[0134] R f 0.36 (25% diethyl ether in hexane)
[0135] Intermediate 11 1-tert-Butoxycarbonyl-1, 2,3,6-tetrahydro-4-(trimethylsilyloxy)pyridine
[0136] Trimethylsilyl chloride (25 ml) and triethylamine (50 ml) were added to a stirred solution of N-Boc piperidinone (30 g) in DMF (40 ml) and the mixture was heated at 70 ° C. for 16 h. The solution was cooled to room temperature and diluted with hexanes (300 ml), the solution was washed with sodium bicarbonate solution (3 x 100 ml), dried (MgSO 4 ) and evaporated to give a colourless oil. The product was purified on silica eluting with 10% ethyl acetate/hexanes to give the title compound as colourless oil (25 g, 62%).
[0137] R f 0.7 (20% EtOAc/hexanes)
[0138] Intermediate 12 1-tert-Butoxycarbonyl-3-bromopiperidin-4-one
[0139] NBS (1.4 g) was added to a solution of 1-tert-butoxycarbonyl-1,2,3,6-tetrahydro-4-(trimethylsilyloxy)pyridine (2 g) in acetonitrile and the mixture was stirred at room temperature for 30 minutes. The solution was diluted with ethyl acetate(50 ml) and washed with water (50 ml), sodium bicarbonate solution (50 ml) and brine (50 ml), dried (MgSO 4 ) and evaporated to give the title compound as a colourless solid (1.8 g).
[0140] R f 0.40 (20% EtOAc/hexanes)
[0141] Intermediate 13 2-Phenyl-4,5,6,7-tetrahydro-thiazolo[5,4c]pyridine
[0142] A solution of 1-tert-butoxycarbonyl-3-bromopiperidin-4-one (8 g) and thiobenzamide (3.4 g) in DMF was heated at 70 ° C. for 16 h, then cooled to room temperature. The solvent was evaporated in vacuo and the residue dissolved in water (100 ml) and washed with ether (100 ml), then basified with sodium hydroxide and extracted into ethyl acetate (3×100 ml). The solvent was dried (MgSO 4 ) and evaporated to give the title compound as cream solid (2.81 g, 53% based on thiobenzamide used). MS 217 (M+1)
EXAMPLE 1
3-Methyl-2-(6-phenyl-3,4-dihydro-1 H-isoquinoline-2-sulfonylmethyl)-butyric acid
[0143] Trifluoroacetic acid (5 ml) was added to a solution of 3-methyl-2-(6-phenyl-3-4-dihydro-1H-isoquinoline-2-sulfonylmethyl)-butyric acid tert-butyl ester (0.33 g) in dichloromethane (20 ml). The reaction was stirred at room temperature for 4 h then evaporated under reduced pressure. Diethyl ether (10 ml) was added to the residue then extracted with 1M sodium hydroxide solution. The aqueous was extracted with diethyl ether (10 ml), acidified with citric acid to pH═3 then extracted with ethyl acetate (3×10 ml). The combined ethyl acetate extracts were washed with water (2×10 ml) and brine (10 ml), dried (Na 2 SO 4 ), filtered and evaporated under reduced pressure to give the title compound (250 mg, 87%) as a white solid.
[0144] R f 0.26 (50% diethyl ether in hexane plus acetic acid) MS 388 (M+1), 386 (M−1)
[0145] The following compound was prepared as above.
EXAMPLE 2
2-(6-Cyclohexyl-3,4-dihydro-1H-isoquinoline-2-sulfonylmethyl)-3-methyl-butyric acid
[0146] From 2-(6-cyclohexyl-3,4-dihydro- 1H-isoquinoline-2-sulfonylmethyl)-3-methyl-butyric acid tert-butyl ester (230 mg) to give the title compound (164 mg, 82%) as a white solid.
[0147] R f 0.27 (50% diethyl ether in hexane plus acetic acid) MS 394 (M+1), 392 (M−1)
EXAMPLE 3
2-(6,7-Dimethoxy-3,4-dihydro-1H-isoquinoline-2 sulfonylmethyl)-3-methyl-butyric acid
[0148] 2-Chlorosulfonylmethyl-3-methyl-butyric acid tert-butyl ester (l.Oml of a 1M solution in dichloromethane) was added to a solution of 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline hydrochloride (230 mg) and triethylamine (0.31 ml) in dichloromethane (10 ml) and the mixture stirred at room temperature for 16 h. Trifluoroacetic acid was added (5 ml) and the reaction left to stir for 2 h then diluted with hexane (10 ml) and evaporated under reduced pressure. The residue was azeotroped with 1:1 dichloromethane-hexane (2×10 ml), dissolved in 1M sodium hydroxide and washed with diethyl ether (2×10 ml); The aqueous was acidified to pH═4 with citric acid and extracted with ethyl acetate (2 xl5 ml). The combined extracts were washed with water (lOmil) and brine (10 ml), dried (Na2SO 4 ), filtered and evaporated under reduced pressure to give the title compound (93 mg, 25%).
[0149] R f 0.43 (5% methanol in dichloromethane) MS (M+1) 372 and (M−1) 370
EXAMPLE 4
3-Methyl-2-(2-phenyl-6,7-dihydro-4 H-thiazolo[5,4-c]pyridine-5-sulfonylmethyl)-butyric acid
[0150] 2-Phenyl-4,5,6,7-tetrahydro-thiazolo[5,4-c]pyridine (0.11 g) was added to a solution of 2-chlorosulfonylmethyl-3-methyl-butyric acid tert-butyl ester (0.14 g) and triethylamine (0.3 ml) in DCM (20 ml) at room temperature. The solution was stirred for 2 h, then TFA (5 ml) was added and the mixture stirred for 1 h. The mixture was evaporated in vacuo and the residue partitioned between diethyl ether (10 ml) and saturated sodium bicarbonate (30 ml). The aqueous layer was acidified with citric acid to pH 5 and extracted with ethyl acetate (3×20 ml). The solvent was dried (MgSO 4 ) and evaporated to give the title compound as pale yellow solid (0.15 g).
[0151] R f 0.32 (EtOAc)
EXAMPLE 5
1-[2-(3,4-Dihydro-1H-isoquinoline-2 sulfonyl)-1-hydroxycarbamoyl-ethyl]-piperidine-1-carboxylic acid benzyl ester
[0152] Trifluoroacetic acid (5.0 ml) was added to a solution of 4-[1-tert-butoxycarbonyl-2-(3,4-dihydro-1H-isoquinoline-2-sulfonyl)ethyl]-piperidine-1-carboxylic acid benzyl ester (506 mg) in dichloromethane (30 ml). The reaction was stirred at room temperature for 3.5 h then the solvent and excess trifluoroacetic acid evaporated under reduced pressure to give the carboxylic acid as a yellow solid. This was dissolved in dichloromethane (30 ml) under a nitrogen atmosphere and oxalyl chloride (0. lml) added, followed by N,N-dimethylformamide (a few drops, catalytic). The reaction was left to stir for 16 h then evaporated under reduced pressure to give the acid chloride as a yellow solid. This was suspended in tetrahydrafuran (10 ml) and 50% wt solution of aqueous hydroxylamine (0.30 ml) was added. The reaction was left to stir at room temperature for 20 minutes then the solvent was evaporated under reduced pressure. The residue was triturated with water (20 ml), the resulting solid filtered off and washed with water (10 ml). Purification by reverse phase preparative HPLC using a 25 cm×21.4 mm Phenomenex Luna C18 (2) (5 u) column and a mobile phase of aqueous trifluoroacetic acid (0.05% v/v) and acetonitrile under gradient conditions from 20% to 70% acetonitrile gave the title compound (83 mg, 18%) as a pale yellow solid, >98% pure by HPLC analysis.
[0153] R f 0.18 (5% methanol in dichloromethane) MS 500 (M−1)
EXAMPLE 6
2-(6-Cyclohexyl-3,4-dihydro-1H-isoquinoline-2-sulfonylmethyl)-N-hydroxy-3-methyl-butyramide
[0154] 2-(6-Cyclohexyl-3,4-dihydro- 1H-isoquinoline-2-sulfonylmethyl)-3-methyl-butyric acid (143 mg) was dissolved in dichloromethane (15 ml) under a nitrogen atmosphere and oxalyl chloride (0.15 ml) added, followed by a solution of 10% N,N-dimethylformamide in dichloromethane (7 drops). The reaction was stirred at room temperature for 2 h then evaporated under reduced pressure and azeotroped with 1:1 dichworomethane-hexane (2×10 ml). The residue was dried under vacuum then suspended in tetrahydrofuran (15 ml) and treated with 50% wt solution of aqueous hydroxylamine (0.7 ml). The mixture was left to stir at room temperature for lh then evaporated under reduced pressure. The residue was triturated with water (20 ml) and the resulting solid filtered off, washed with water (10 ml) and dried under vacuum at 40 ° C. to give the title compound (120 mg, 82%).
[0155] R f 0.32 (5% methanol in dichloromethane) MS 407 (M−1)
[0156] The following compounds were prepared as above.
EXAMPLE 7
N-flydroxy-3-methyl-2-(6-phenyl-3 ,4-dihydro-IH-isoquinoline-2-sulfonylmethyl)-butyramide
[0157] From 3-methyl-2-(6-phenyl-3,4-dihydro-1H-isoquinoline-2-sulfonylmethyl)-butyric acid (230 mg), to give the title compound (220 mg, 93%).
[0158] R f 0.28 (5% methanol in dichloromethane) MS 403 (M+1)
EXAMPLE 8
2 (6,7-Dimethoxy-3,4 dihydro-1H-isoquinoline-2 sulfonylmethyl)-N-hydroxy-3-methyl-butyramide
[0159] From 2-(6,7-dimethoxy-3,4-dihydro-1H-isoquinoline-2-sulfonylmethyl)-3-methyl-butyric acid (80 mg), to give the title compound (71 mg, 85%).
[0160] R f 0.27 (5% methanol in dichloromethane) MS 387 (M+1)
EXAMPLE 9
N-Hydroxy-3-methyl-2-(2-phenyl-6,7-dihydro-4 H-thiazolo[5,4-c]pyridine-5-sulfonylmethyl)-butyramide
[0161] From 3-methyl-2-(2-phenyl-6,7-dihydro-4 H-thiazolo[5,4-c]pyridine-5 sulfonyl methyl)-butyric acid (0.15 g), to give the title compound as beige solid (85 mg).
[0162] R f 0.33 (7% MeOH/DCM) MS 409 (M+1) | A phacologically actve compound of forula (1)
wherein
R 1 is OH or NHOH
R 2 is H, alkyl, alkenyl, aryl, arylakyl, heteroaryl, heteroarylalkyl, cycloalkyl, cycloakylalkyl, heterocyclo, or heterocycloalkyl (any of which may be optionally substituted with one or more substituents selected from R 6 , W and WR 6 ); and
R 3 is H or alkyl;
or R 2 , R 3 and the carbon atom to which they are attached together represent a carbocyclic or heterocyclic ring (either of which may be substituted with one or more substituents selected fom R 6 , W and WR 6 );
R 4 is alkyl, cycloalkyl, OR 9 , CO 2 R 14 , COR 10 , S(O) q R 10 where q is 0.1 or 2, CONR 7 R 8 , CN or S(O) q NR 7 R 4 ; substituents may be attached to th same carbon atom to from C(R 4 ) 2 , where each R 4 may be the same or dfferent, and C(R 4 ) 2 may represent C═O;
R 5 is aklyl, cycloalkyl, aryl, heteroaryl, hetrocyclo, CF 3 , OR 9 , COR 10 , S(O) 9 R 10 , CO 2 R 14 , CONR 7 R 8 , S(O)NR 7 R 8 . halogen, NR 10 R 11 or CN, or two adjacent R 5 substituents may be combined to form a heterocyclic ring,
R 6 is OR 9 , COR 10 , CO 2 R 15 , CONR 7 R 8 , NR 10 R 11 , S(O) 9 R 10 , S(O) 9 NR 7 R 8 , ═O, ═NOR 10 , succinimido or the group
R 7 and R 8 , which may be the same or different, are each H, alkyl, cycloalkyl, aryl, heteroaryl, heterocyclo, arylalkyl, heterarylalkyl, heterocycloalkyl, or cycloalkylalkyl, or R 7 and R 8 and the nitrogento which they are attached together represent a heterocyclic ring;
R 9 is alkyl, CF 3 , CHF 2 , CH 2 F, cycloalkyl, aryl, heterocyclo, arylalkyl, heterarylalkyl, heterocycloalkyl or cycloalkylalkyl,
R 10 is H, alkyl, cycloalkyl, aryl, heteraryl, heterocyclo, arylalkyl, heterarylalkyl, heterocycloalkyl or cycloalkylalkyl; and
R 11 is H, alkyl, cycloalkyl, aryl, heteroaryl, heterocyclo, arylalkyl, heterarylalkyl, heterocycloalkyl, cycloalkylalkyl, COR 12 , CONR 7 R 8 , S(O) q R 12 or S(O) q NR 7 R 8 ;
or R 10 and R 11 and the nitrogen to which they are attatched together represent a heterocyclic ring;
R 12 is OR 9 or R 13 ;
R 13 is alkyl, cycloalkyl, aryl, heteroaryl, heterocyclo, arylalkyl, heterarylalkyl, heterocycloalkyl or cycloalkylalkyl;
R 14 is H, alkyl, or cycloalkyl;
R 15 is H, alkyl, cycloalkyl, arylalkyl or heteroarylalkyl;
R 16 is H or alkyl,
A is aryl or heteroaryl, provided that when A is phenyl, R 3 is H,
W is alkyl, cycloalkyl, cycloalkylalkyl, aryl, arylalkyl, heteroaryl, heteroarylalkyl, heterocyclo or haterocycloalkyl,
each k and m is independently 0, 1, 2 or 3;
n is 0 or 1; and
p is 0, 1 or 2;
or a salt, solvate, hydrate, N-oxide, protected amino, protected carboxy or protected hydroxamic acid derivative thereof | 2 |
This application is a continuation-in-part of application Ser. No. 09/488,426 filed Jan. 20, 2000, now abandoned, which application claims priority to Ser. No. 60/117,162 filed Jan. 25, 1999 and application Ser. No. 09/488,376 filed Jan. 20, 2000, now abandoned, which application claims priority to Ser. No. 60/117,163 filed Jan. 25, 1999.
BACKGROUND OF THE INVENTION
In the manufacture of paper products, such as facial tissue, bath tissue, paper towels, dinner napkins and the like, a wide variety of product properties are imparted to the final product through the use of chemical additives. Examples of such additives include softeners, debonders, wet strength agents, dry strength agents, sizing agents, opacifiers and the like. In many instances, more than one chemical additive is added to the product at some point in the manufacturing process. Unfortunately, there are instances where certain chemical additives may not be compatible with each other or may be detrimental to the efficiency of the papermaking process, such as can be the case with the effect of wet end chemicals on the downstream efficiency of creping adhesives. Another limitation, which is associated with wet end chemical addition, is the limited availability of adequate bonding sites on the papermaking fibers to which the chemicals can attach themselves. Under such circumstances, more than one chemical functionality compete for the limited available bonding sites, oftentimes resulting in the insufficient retention of one or both chemicals on the fibers.
Therefore, there is a need for a means of applying more than one chemical functionality to a paper web that mitigates the limitations created by limited number of bonding sites. More specifically, there is a need to provide resins combining the humectancy of a polyether with the ability to form crosslinked thermoset resins such that these materials will function effectively as wet strength agents for tissue.
SUMMARY OF THE INVENTION
It has been discovered that two or more chemical functionalities can be combined into a single molecule, such that the combined molecule imparts at least two distinct product properties to the final paper product that heretofore have been imparted through the use of two or more different molecules. More specifically, certain amphiphilic hydrocarbons can be incorporated into the backbone of modified condensation polymers containing azetidinium groups or other such groups capable of either crosslinking with cellulose or the polymer molecules themselves, such as polyamide epichlorohydrin (PAE) resins, into a single molecule that provides several potential benefits, depending upon the specific combination employed, including: (a) wet strength aids that impart softness; (b) softeners that do not reduce wet strength: (c) wet strength with improved wet/dry strength ratio; (d) surface feel modifiers with reduced linting and sloughing; (e) wet strength aids with controlled absorbency; (f) wet strength aids with controlled decay rate after wetting; and (g) Yankee dryer additives that provide surface protection and adhesion with controlled release properties.
Hence in one aspect, the invention resides in a condensation polymer comprising the reaction product of two or more reactant compounds which include an amphiphilic difunctional polyoxyalkylene compound, a difunctional polyalkylene compound having at least one unreacted secondary amine group and, optionally, a difunctional saturated aliphatic hydrocarbon or a difunctional ether, wherein at least a portion of the secondary amine groups in the resulting condensation polymer have been reacted to incorporate groups capable of forming covalent bonds with cellulose or with other polymer molecules.
More specifically, the invention resides in condensation polymers having the following general structure:
where
a, b, w≧1; c≧0; Z 1 , Z 2 , Z 3 =bridging radicals including —OOC—, —COO—, —NHCO—, —OCNH—, —O—, —S—, —CONHCO—, —NCOO—, —OSO 2 O—, OCOO, —OOC—Ar—O—, or any other suitable bridging radical. Z 1 , Z 2 , Z 3 can be the same or different. The purpose of the Z 1 , Z 2 , Z 3 radicals is to incorporate the R 1 , R 2 , and R 3 groups into the polymer. The Z groups can also contain aryl functionality. R 1 =an amphiphilic hydrocarbon residue derived from a polyether; R 2 =a linear or branched, saturated or unsaturated, substituted or non-substituted aliphatic hydrocarbon containing at least one secondary amine group wherein at least a portion of the secondary amine groups in the final polymer have been reacted in such a manner so as to incorporate groups capable of forming covalent bonds either with cellulose or with other polymer molecules; and R 3 =a linear or branched, substituted or non-substituted aliphatic hydrocarbon having from about 1 to 24 carbon atoms including mixtures of said compounds. R 3 can also be a bis-functional ether of a linear or branched, substituted or non-substituted saturated aliphatic hydrocarbon having from 2 to 24 carbons.
A feature of the condensation polymers of this invention is that the amphiphilic polyether portion of the polymer (R 1 ) is built into the backbone of the polymer and not pendant to the main polyamidoamine chain. By incorporating the polyether portion in a linear fashion into the backbone of the polymer, branching and crosslinking are minimized, thus making the polymers of this invention well-suited for use as wet strength agents.
In another aspect, the invention resides in a tissue or towel sheet, comprising an amount of a condensation polymer as described above.
In another aspect, the invention resides in a method of making a paper sheet such as a tissue or towel sheet, comprising the steps of: (a) forming an aqueous suspension of papermaking fibers; (b) depositing the aqueous suspension of papermaking fibers onto a forming fabric to form a web; and (c) dewatering and drying the web to form a paper sheet, wherein a condensation polymer is added to the aqueous suspension, said condensation polymer having the structure described above.
The amount of the condensation polymer of this invention added to the fibers can be from about 0.01 to about 3 weight percent, on a dry fiber basis, more specifically from about 0.02 to about 2 weight percent, and still more specifically from about 0.05 to about 1.5 weight percent. The modified condensation polymer(s) can be added to the fibers at any point in the process where the fibers are suspended in water.
Methods of making paper products which can benefit from the various aspects of this invention are well known to those skilled in the papermaking art. Exemplary patents include U.S. Pat. No. 5,785,813 issued Jul. 28, 1998 to Smith et al. entitled “Method of Treating a Papermaking Furnish For Making Soft Tissue”; U.S. Pat. No. 5,772,845 issued Jun. 30, 1998 to Farrington, Jr. et al. entitled “Soft Tissue”; U.S. Pat. No. 5,746,887 issued May 5, 1998 to Wendt et al. entitled “Method of Making Soft Tissue Products”; and U.S. Pat. No. 5,591,306 issued Jan. 7, 1997 to Kaun entitled “Method For Making Soft Tissue Using Cationic Silicones”, all of which are hereby incorporated by reference.
DETAILED DESCRIPTION OF THE INVENTION
The condensation polymers of this invention comprise the reaction product of an amphiphilic difunctional polyoxyalkylene compound and a difunctional polyalkylene compound having at least one unreacted secondary amine group and, optionally, a saturated aliphatic difunctional hydrocarbon or ether. In addition, a portion of the secondary amine groups have been reacted in such a manner as to incorporate groups capable of forming covalent bonds either with cellulose or with other polymer molecules.
In preparing the condensation polymers of this invention, the amphiphilic difunctional polyoxyalkylene compound has the formula:
Z 5 −R 1 −Z 6
wherein
Z 5 and Z 6 are functional groups, which can be the same or different, such that each Z-group must be capable of reacting with at least one other Z-group in order to incorporate the R-group functionality into the molecule; and R 1 is defined as above.
The polyoxyalkylene component as referred to herein is derived from polyethers and in one embodiment has a structure:
—(R 7 O) h —
wherein
R 7 =saturated, linear or branched, substituted or non-substituted aliphatic hydrocarbons having 10 or fewer carbon atoms; and h≧2.
The polyoxyalkylene structure can also exist as a series of independently different aliphatic hydrocarbon ether units. The individual units may be arranged in any fashion within the polyether structure. Such compounds will have the formula:
—[(R 8 O) j —(R 9 O) k — . . . —(R n O) z —] w —
wherein:
R 8 , R 9 , R n =saturated, linear or branched, substituted or non-substituted aliphatic hydrocarbon of 10 or fewer carbon atoms; j, k . . . z≧0 such that the sum of j, k . . . z is ≧1; and w≧1.
The difunctional polyalkylene component having at least one unreacted secondary amine group has the formula:
Z 7 −R 2 −Z 8
wherein
Z 7 and Z 8 are functional groups, which can be the same or different, such that each Z-group must be capable of reacting with at least one other Z-group in order to incorporate the R-group functionality into the molecule; and R 2 is defined as above.
The optional difunctional saturated aliphatic hydrocarbon or difunctional ether has the following structure:
Z 9 −R 3 −Z 10
wherein
Z 9 and Z 10 are functional groups, which can be the same or different, such that each Z-group must be capable of reacting with at least one other Z-group in order to incorporate the R-group functionality into the molecule; and R 3 is defined as above.
Examples of suitable functional Z-groups described above include, but are not limited to: —COOH, —COOR 4 , —COX, —OCH 2 COOH, —OCH 2 COOR 4 , —OCH 2 COX, —NH 2 , —OH, —SH, —OCOX, —OCOOR 4 , —CN, —NCO, and the like;
wherein R 4 =methyl or ethyl and “X”=halogen.
Examples of suitable amphiphilic hydrocarbon residues derived from a polyether (R 1 ) include, but are not limited to, structures such as:
where:
R 5 , R 6 =independently H or CH 3 ; a, b, c≧0; a+b+c≧2; and x=2 to 6.
Examples of suitable aliphatic hydrocarbon residues containing at least one secondary amine group (R 2 ) include, without limitation, the following structures:
—(C n H 2n NH) x —C n H 2n —
where “n” is an integer of 2 or greater and “x” is an integer of 1 or greater.
Examples of suitable difunctional polyalkylene compounds having at least one unreacted secondary amine group (Z 7 -R 2 -Z 8 ) include, without limitation, the following structures:
NH 2 —(C n H 2n NH) x —H
NH 2 CH 2 CH 2 NHCH 2 CH 2 NH 2
HOOCCH 2 NHCH 2 COOH
HOCH 2 CH 2 NHCH 2 CH 2 OH
NH 2 CH 2 CH 2 NHCH 2 CH 2 OH
HOOCCH 2 CH 2 NHCH 2 CH 2 COOH
NH 2 CH 2 CH 2 NHCH 2 CH 2 NHCH 2 CH 2 NH
and
HN(CH 2 CH 2 CN) 2
wherein “n” and “x” are integers of 2 or more.
Examples of suitable difunctional saturated aliphatic hydrocarbons and difunctional ethers (Z 9 -R 3 -Z 10 ) include, but are not limited to, adipic acid, malic acid, malonic acid, glutaric acid, oxalic acid, succinic acid, methyl malonic acid, citramalic acid, 2-methylglutaric acid, 3-methylglutaric acid, dimethylglutaric acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioc acid, dodecanedioc acid, 1,12-dodecanedicarboxylic acid, hexadecanedioc acid, octadecanedioc acid, dodecyldioic acid, diglycolic acid, their corresponding methyl and ethyl esters, acid chlorides and mixtures of said compounds.
With regard to reaction of the secondary amine groups to add groups capable of forming covalent bonds with cellulose or other polymer molecules, such reactions of the secondary amine group are well known to those skilled in the art. Preferred functional groups are azetidinium, epoxy, silanol and mixtures of said groups. A key element in this regard is that the reaction take place in such a way that crosslinking between individual polymer molecules is kept to a minimum prior to addition of the polymer to the cellulose.
In order to use the condensation polymers of this invention as wet strength agents, it is desirable to insure that the crosslinking reaction between polymer molecules is appreciably minimized until after addition to the pulp fibers and sheet formation. Pre-crosslinked high molecular weight and highly branched versions find a variety of uses as flocculation and drainage aids, retention aids and sundry other process aid applications but are generally not suitable for wet strength applications where essentially linear resins are preferred. For wet strength resins, molecular weights can be about 1,000,000 or lower, more specifically about 500,000 or lower, and still more specifically from about 10,000 to about 250,000.
Difunctional polyoxyalkylene compounds typically have free hydroxyl groups at the terminal ends of the polymer wherein Z 5 and Z 6 are —OH. The —OH groups are capable of undergoing condensation reactions to form polymers and thus are suitable for incorporation into the polymers of the invention. There are derivatives of these compounds including the dithiol, diisocyanate, diacid and diamine derivatives which are also suitable and may be preferred for incorporation of the polyoxyalkylene element into the polymer backbone. Both the diacid, Z 5 , Z 6 =—OCH 2 COOH, and diamine derivatives, Z 5 , Z 6 =—NH 2 are known commercially available materials. One especially preferred class of difunctional polyoxyalkylene compounds is the amino functional polyethers, often referred to as polyalkyleneoxy amines. The polyalkyleneoxy amines are well known compositions that may be prepared by the reductive amination of polyalkyleneoxy alcohols using hydrogen and ammonia in the presence of a catalyst. This reductive amination of polyols is described in U.S. Pat. Nos. 3,128,311; 3,152,998; 3,236,895; 3,347,926; 3,654,370; 4,014,933; 4,153,581 and 4,766,245. The molecular weight of the polyalkyleneoxy amine material, when employed is preferably in the range of from about 100 to about 5,000. Additional examples of amine containing polymers having carbon—oxygen backbone linkages and their uses are described in U.S. Pat. Nos. 3,436,359; 3,155,728; and 4,521,490. Examples of suitable commercially available polyalkyleneoxy amines are materials sold under the trade name Jeffamine® and manufactured by Huntsman Chemical Corporation.
On a molar basis, the ratio of the various components in the polymer will vary depending upon the specific compounds and synthesis strategies employed. Ratios of reactive end groups are typically 1:1 molar although slight molar excesses are often used. On a weight basis, the amount of polyether will range from about 2 to about 95 weight percent of the total polymer, more specifically from about 5 to about 80 weight percent, and still more specifically from about 10 to about 60 weight percent.
It will oftentimes be advantageous to incorporate the optional saturated aliphatic hydrocarbon residue, R 3 , into the backbone of the polyamidoamine along with the polyoxyalkylene element. The optional saturated aliphatic hydrocarbon can be linear or branched, substituted or non-substituted aliphatic having from about 1 to 24 carbon atoms. It may also be advantageous to including mixtures of said aliphatic hydrocarbons and such embodiment should be considered within the scope of the invention. R 3 may also be a bis-functional ether of a linear or branched, substituted or non-substituted aliphatic hydrocarbon having from 2 to 24 carbons. The bis-functional ethers being distinct from the di-functional polyoxyalkylene derivatives in that the polyoxyalkylene derivatives are characterized by having a multiplicity of ether groups whereas the bis-functional ethers contain only one such ether group. As such, the bis-functional ethers do not demonstrate the humectant properties of the polyoxyalkylene materials, instead behaving more like a saturated aliphatic hydrocarbon.
There are a variety of ways in which the saturated aliphatic hydrocarbon can be incorporated into the backbone of the polymer. A preferred approach is to use a dibasic acid, acid halide, methyl ester, or ethyl ester of a saturated aliphatic hydrocarbon having from 2 to 24 carbon atoms. The most preferred approach is to use the dibasic acid.
Examples of suitable dibasic acids of aliphatic hydrocarbons and bis-functional ethers include but are not limited to, adipic acid, malic acid, malonic acid, glutaric acid, oxalic acid, succinic acid, methyl malonic acid, citramalic acid, 2-methylglutaric acid, 3-methylglutaric acid, dimethylglutaric acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioc acid, dodecanedioc acid, 1,12-dodecanedicarboxylic acid, hexadecanedioc acid, octadecanedioc acid, dodecyldioic acid, diglycolic acid, their corresponding methyl and ethyl esters, acid chlorides and mixtures of said compounds. The amount of difunctional aliphatic hydrocarbon relative to difunctional polyoxyalkylene compound will vary depending upon the particular application. In general the amount of difunctional aliphatic hydrocarbon will range from 0% to about 98% by weight of the amount of difunctional polyoxyalkylene compound, more specifically from about 10% to about 95% and most specifically from about 20% to about 85% by weight of the amount of difunctional polyoxyalkylene compound.
The reaction of the difunctional polyalkylene compound having at least one unreacted secondary amine group, the difunctional polyoxyalkylene compound, and optional saturated aliphatic difunctional hydrocarbon can be done by any of the various methods known to those skilled in the art. A typical reaction involves adding the various reactants into a reaction vessel, heating the reaction vessel to an elevated temperature in excess of 100° C., typically from around 150° C. to around 250° C., optionally under a nitrogen atmosphere, and removing the by-products of the condensation reaction, usually water. Reaction takes place until by-product removal is complete. Catalysts, vacuum and other process techniques can be employed to help drive the reaction to completion. The molecular weight of the polymer can be controlled by controlling the extent of reaction, the extent of reaction monitored by measuring the amount of by-product evolved and comparing to the 100% theoretical amount. Such techniques are well known to those skilled in the art. Molecular weight may also be controlled via addition of mono-functional additives, again such techniques being well known to those skilled in the art. Both intermediate condensation polymer and finished product formulation may include biocides, antioxidants, and other aids to improve storage and handling capabilities. Such variations should be understood to be within the scope of the invention.
Formation of the crosslinking entity takes place after the formation of the polyamidoamine is complete. Reaction with epichlorohydrin to form hydroxy azetidinium groups, for example, can be accomplished using the following procedure. The polyamidoamine polymer is diluted with water to a concentration of about 10% to about 70% solids, preferably from about 10% to about 30% solids. From about 0.05 to about 1.2 molar equivalents, preferably from about 0.10 to about 0.8 molar equivalents, of epichlorohydrin based on secondary amine content of the base resin is added to the aqueous solution at a temperature of 60° C. or lower. Reaction continues until a substantial amount of the epichlorhydrin, typically 60-100% has reacted. While maintaining a temperature between 20° C. and 100° C., Sulfuric acid or other mineral acid is added at a rate of from about 0.1 to about 30% of an equivalent based on the amount of secondary amine in the starting polyamidoamine. Reaction is then continued at a temperature between 20° C. and 100° C., preferably from about 20° C. to 80° C. to affect isomerization of N-chlorohydrin groups to 3-hydroxyazetidinium groups. Some crosslinking may occur during this reaction but should be minimized through careful selection of reaction temperatures, pH and concentration of the polymer in solution.
Typically, only a portion of the secondary amine groups are functionalized with the crosslinking moiety. Preferably from about 5 to about 60% of the secondary amine groups have been functionalized, most preferably from about 10 to about 50%. Higher levels of functionalization up to 100% can be used provided the crosslinking groups are capable of forming covalent bonds with cellulose.
When the condensation polymers of this invention are PAE resins, the polymers of this invention are expected to show the same traits as standard commercially available PAE wet strength resins such as Kymene 557 manufactured and sold by Hercules, Inc. As such they would be expected to be stabilized by acidification to a pH of 3.5-6.0 at the end of the polymerization reaction and generally shipped/stored as aqueous solutions of 12-33% solids. As with other PAE resins, they are thermosets and they will polymerize with themselves to water insoluble materials by action of heat alone.
In papermaking systems, typical addition levels will be on the order of 0. 10% to 4.0% by weight of dry fiber, more specifically from about 0.2% to 3.0% by weight of dry fiber. They should be effective when employed across a pH range of 5-9. Best resin distribution will be achieved when the resin solution is diluted at least 10:1 with fresh water. Active chlorine will react with PAE resins to reduce their effectiveness. At low pH resins are less effective due to inadequate ionization of the pulp carboxyl groups and also the secondary amine groups become protonated and can not readily participate in cross linking reactions with azetidinium groups.
Crosslinking groups are not limited to hydroxyazetidinium. It is known that the polyamidoamines can also be reacted in a manner to give other functional groups capable of crosslinking with other polymer molecules or cellulose. In particular it is known that silanol and epoxy groups can be added to the polymer backbone and can be done with or without presence of hydroxyazetidinium groups. Such groups should also be recognized as falling within the scope of the invention as well as mixtures of said groups.
The reaction between PAE and anionic materials has been disclosed and can be beneficial in enhancing resin retention by fibers. This is illustrated by the use of anionic carboxymethyl cellulose in conjunction with PAE resin to improve wet strength performance. In this case it is believed that the CMC and PAE resin form a weakly cationic complex called a “symplex” that absorbs onto fiber surfaces. The CMC provides the carboxyl groups necessary to attract more PAE onto the fiber surface. It is expected that the resins of this invention would behave similarly and it is within the scope of the invention to use such materials as CMC in conjunction with the polymers of the invention to improve wet strength performance.
Where enhanced cationicity is desired, difunctional compounds containing tertiary amine groups may also be employed. These tertiary amine groups are capable of being quaternized via reaction with epichlorohydrin as is routinely done with cationic starches, however, they can not be isomerized to hydroxyazetidinium groups.
One skilled in the art will recognize that in the aforementioned process the polyoxyalkylene entity will be incorporated into the polymer backbone in a random manner. It may at times be advantageous to incorporate the amphiphilic hydrocarbon moiety as a block copolymer into the backbone of the polymer. This may be accomplished via a mono- or di-substituted copolymer containing linear or branched, substituted or unsubstituted, saturated or unsaturated, amphiphilic hydrocarbon moieties. Finished polymers will have a structure.
wherein
m=1 to 5000; n=10to 5000; and R 1 , R 2 , R 3 , Z 1 , Z 2 and Z 3 are as defined above.
EXAMPLES
Example 1
75 grams (0.3 moles) of poly(ethylene glycol) bis(carboxymethyl) ether having a molecular weight of 250 grams, 102 grams (0.7 moles) of adipic acid and 114 grams (1.1 moles) of diethylene triamine are charged to a three-neck flask equipped with a mechanical stirrer, thermometer and water trap. The solution is heated to 160° C. for 105 minutes as the temperature rises to around 195° C. The contents of the flask are poured into a large beaker and cooled to room temperature. The resultant polyamidoamine is then dissolved in approximately 600 cc of water to make a 30% solids solution. The solution is charged to a 3 neck flask equipped with a condenser, mechanical stirrer and addition funnel. The solution is heated to 40° C. and 47 grams (0.5 moles) of epichlorhydrin are added at a rate so as to maintain the temperature between 40° C. and 50° C. After addition is complete, the epichlorhydrin is allowed to react for an additional 120 minutes at a temperature between 40° C. and 45° C. 550 cc of a 2% w/w sulfuric acid solution are added and the temperature is raised to 60° C. and the reaction is allowed to continue for an additional 90 minutes. The pH is then adjusted to between 3.5 and 6 and the solids content adjusted to 5-15%. The overall reaction is shown in FIG. 1.
wherein:
m, n and p are moles of respective compound such that: m, n, p>0; and m+n=0.8-1.2 p.
Example 2
This example illustrates the reaction between a polyoxyalkylene diamine, a dibasic acid of an aliphatic hydrocarbon and a polyamine. 146 grams (1.0 moles) of adipic acid, 84 grams (0.8 moles) of diethylene triamine and 180 grams (0.3 moles) of Jeffamine ED-600® (a commercially available poly(oxyalkylene) diamine having the formula set forth in FIG. 2 below wherein a+c=about 2.5 and b=about 8.5) are charged to a 3-neck reaction flask equipped with a mechanical stirrer, thermometer and water trap condenser. The solution is heated to 160° C. and the reaction is allowed to proceed until about 85% of the theoretical water is removed. The contents of the flask are then poured into a large beaker and allowed to cool to room temperature. Distilled water is added to bring the solution to about 40% solids. The polymer solution is then charged to a reaction flask equipped with a condenser, mechanical stirrer and addition funnel. The solution is heated to 40° C. and 42 grams (0.45 moles) of epichlorhydrin are added at a rate so as to maintain the temperature between 40° C. and 50° C. After addition is complete, the epichlorhydrin is allowed to react for an additional 120 minutes at a temperature between 40° C. and 45° C. 550 cc of a 2% w/w sulfuric acid solution are added and the temperature is raised to 60° C. and the reaction is allowed to continue for an additional 90 minutes. The pH is then adjusted to between 3.5 and 6 and the solids content adjusted to 5-15%. The overall reaction is shown in FIG. 2 below.
wherein:
m, n, p>0; n+p=m; a+c=2.5; and b=8.5.
Example 3
This example illustrates the use of the condensation polymer of this invention to modify cellulosic sheets. 50 grams (oven-dry basis) of a blend of 65% Eucalyptus hardwood Kraft fiber and 35% by weight Northern Softwood Kraft fiber is soaked in 2 liters of water for 5-minutes. The pulp slurry is then disintegrated for 5 minutes in a British disintegrator. The slurry is then diluted with water to a volume of 8 liters. The chemical of example 2 is diluted to a 1% by weight solution and 25 grams of the 1% polymer solution is added to the pulp slurry to give a chemical concentration of 0.5% by weight of dry fiber. The slurry is mixed with a standard mechanical mixer at moderate shear for 10 minutes after addition of the first chemical.
Handsheets are made with a basis weight of 60 gsm. During handsheet formation, the appropriate amount of fiber (0.625% consistency) slurry required to make a 60 gsm sheet is measured into a graduated cylinder. The slurry is then poured from the graduated cylinder into an 8.5-inch by 8.5-inch Valley handsheet mold (Valley Laboratory Equipment, Voith, Inc.) that has been pre-filled to the appropriate level with water. After pouring the slurry into the mold, the mold is then completely filled with water, including water used to rinse the graduated cylinder. The slurry is then agitated gently with a standard perforated mixing plate that is inserted into the slurry and moved up and down seven times, then removed. The water is then drained from the mold through a wire assembly at the bottom of the mold that retains the fibers to form an embryonic web. The forming wire is a 90×90 mesh, stainless-steel wire cloth. The web is couched from the mold wire with two blotter papers placed on top of the web with the smooth side of the blotter contacting the web. The blotters are removed and the embryonic web is lifted with the lower blotter paper, to which it is attached. The lower blotter is separated from the other blotter, keeping the embryonic web attached to the lower blotter. The blotter is positioned with the embryonic web face up, and the blotter is placed on top of two other dry blotters. Two more dry blotters are also placed on top of the embryonic web. The stack of blotters with the embryonic web is placed in a Valley hydraulic press and pressed for one minute with 100 psi applied to the web. The pressed web is removed from the blotters and placed on a Valley steam dryer containing steam at 2.5 psig pressure and heated for 2 minutes, with the wire-side surface of the web next to the metal drying surface and a felt under tension on the opposite side of the web. Felt tension is provided by a 17.5 lbs of weight pulling downward on an end of the felt that extends beyond the edge of the curved metal dryer surface. The dried handsheet is trimmed to 7.5 inches square with a paper cutter and then weighed in a heated balance with the temperature maintained at 105° C. to obtain the oven dry weight of the web. Flexible sheets are formed that show improved wet tensile strength relative to a control with no chemical.
Example 4
This example illustrates how the condensation polymers of this invention can be used in conjunction with anionic resins such as carboxymethyl cellulose (CMC) to enhance wet strength performance. 50 grams (oven dried basis) of Northern Softwood Kraft fibers is diluted to 2.5% consistency with water, soaked for 5 minutes and dispersed using a British Pulp Disentegrator for 5 minutes.
25 mls of a 1% solution of the chemical of example 2 is added to the thick stock and mixed for 2 minutes using a standard mechanical mixer and moderate sheer. 12.5 grams of a 0.5% aqueous solution of CMC is then added to the thick stock and the slurry is stirred for 2 more minutes under moderate sheer. Handsheets are made with a basis weight of 60 gsm by measuring the appropriate amount of fiber slurry required to make a 60 gsm sheet into a graduated cylinder. The slurry is then poured from the graduated cylinder into a handsheet making mold apparatus, which has been pre-filled to the appropriate level with water. The fibers suspended in the handsheet mold water are then mixed using a perforated plate attached to a handle to uniformly disperse the fibers within the entire volume of the mold. After mixing, the sheet is formed by draining the water in the mold, thus depositing the fibers on the 90×90 mesh forming wire. The sheet is removed from the forming wire using blotters and a couch roll. The wet sheet is then transferred directly to a steam heated, convex surface metal dryer maintained at 213° F. (+2° F.). The sheet is held against the dryer by use of a canvas under tension. The sheet is allowed to dry for 2 minutes on the metal surface, and is then removed. The resultant sheets exhibit good flexibility and improved wet and dry strength over an untreated control.
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. | Modified condensation polymers containing azetidinium groups, such as polyamide epichlorohydrin (PAE) resins, can be combined with amphiphilic hydrocarbons containing polyethers into a single molecule to provide several potential benefits, depending upon the specific combination employed, including: (a) wet strength aids that impart softness; (b) softeners that do not reduce wet strength: (c) wet strength with improved wet/dry strength ratio; (d) surface feel modifiers with reduced linting and sloughing; (e) wet strength aids with controlled absorbency; (f) wet strength aids with controlled decay rate after wetting; and (g) Yankee dryer additives that provide surface protection and adhesion with controlled release properties. | 3 |
FIELD OF THE INVENTION
[0001] The present invention generally relates to interactive gaming systems, and more specifically to on-line gaming systems wherein gaming clients are automatically configured and updated.
BACKGROUND OF THE INVENTION
[0002] A common trend is emerging in modern designs of basic operating systems for computer systems, wherein the need to store more and more complex configuration information is steadily increasing. Moreover, to support new hardware configurations, as well as new software applications, storage of hardware settings into non-volatile memory is required, which in many cases needs to be done individually for each product out of a plurality of products. The storage of this configuration setting in the non-volatile memory requires greater use of non-volatile memory, and is highly product and version specific. As new products are developed and new versions introduced, more information to distinguish one product from another is added to the configuration register, to adequately describe differences among various products, as well as to adjust to personal preferences of an individual user of a given product. Some of these requirements have been described for example in U.S. Pat. No. 5,999,989 to Patel, issued Dec. 7, 1999.
[0003] In this context, new and exciting developments are currently taking place in computer gaming using gaming consoles (GC), and especially in interactive on-line computer gaming. During the last couple of years, on-line computer gaming has gained increasing popularity, and different Gaming Service Providers (GSP) have established themselves on the Internet network. On-line computer gaming is fast becoming a major money generating competitive virtual sport with tournament organizations and ranking services dedicated to providing the on-line community with the latest information and current rankings of global Internet gamers and game players. An interactive game server and on-line community forum is described for example in U.S. Pat. No. 6,339,761 to Sparks II, issued Mar. 5, 2002.
[0004] Computer gaming is constantly growing. Today thousands of players are playing on-line all around the world. Many people stereotype these people as techno kids only, but this could not be more wrong. Both females and males of all ages can be found daily trying to out-think, out-maneuver, or just having a good time on-line. On the Eve of the Electronic Entertainment Expo (E3Expo), the world's largest trade event showcasing computer and video games and related products, a new survey by Peter D. Hart Research Associates, Inc., has found that three-in-five Americans age six or older, or about 145 million people, say they routinely play computer or video games, and that nearly half of these game players are female. It is predictable that interactive on-line computer gaming will blur the line between games and other entertainment or communication media, and that the avenues explored in the development of on-line gaming might well break new ground for interactive Internet applications in all areas of business relations and social life.
[0005] Given the ongoing dynamic developments as well as future directions in the field of interactive on-line gaming, it would be highly advantageous to provide on-line gaming systems, wherein the configuration of a gaming console or any other gaming environment is automatically adjusted. This way, a system is able to easily react to flexible gaming scenarios, to be easily extendable to fulfill other functionalities besides gaming, to be easily adjustable according to certain user specific criteria. In view of the ever-changing world of on-line gaming covering all areas of human interest, some of which are of a restrictive nature for under-age audiences, it would also be highly desirable to achieve a good measure of parental control in interactive on-line computer gaming, yet not to exclude younger participants from possible future forms of social interaction.
OBJECT OF THE INVENTION
[0006] It is therefore an object of the present invention to provide a system and method for interactive on-line gaming that is automatically adjustable to changes in gaming environments and user preferences.
SUMMARY OF THE INVENTION
[0007] In accordance with an aspect of the instant invention, there is provided a gaming console for use as a gaming client and comprising at least a storage medium for having client data relating to a gaming client and for having data relating to a current game in execution stored therein, at least a processor in communication with the at least a storage medium for retrieving game instruction data therefrom and for executing the game instruction data to execute games on the gaming console and for retrieving client data therefrom for executing gaming client functions on the gaming console, and a transceiver for establishing a connection between the gaming console and a service provider, the connection for being controlled by the at least a processor in execution of the client data, wherein some of the client data is for execution of instructions for receiving further client data from the gaming service provider and for storing instruction data within the at least a storage medium and relating to the further client data, the stored instruction data for being executed by the processor to result in execution of gaming client functions, and, wherein the gaming console is absent an operating system supporting multiple simultaneous tasks for execution of multiple simultaneous games.
[0008] In accordance with another aspect of the instant invention, there is provided a method for providing an interactive gaming system service, the method comprising the steps of providing a gaming console comprising a storage medium for storing a gaming client for establishing a connection between the gaming console and a gaming service provider and for controlling events taking place on the gaming console coupling the gaming console to the gaming service provider through a broadband access network, and setting a configuration of the gaming console according to at least one of messages sent to and received from the gaming service provider and messages stored within the gaming console in a personal profile.
[0009] In accordance with yet another aspect of the instant invention, there is provided an interactive gaming system comprising a gaming console comprising at least a storage medium for having data relating to a configuration of the gaming console stored therein, the configuration including a current game in execution, and at least a processor in communication with the at least a storage medium for retrieving data therefrom and executing the data, the data relating to the configuration of the gaming console, a gaming service provider for providing instruction data to the gaming console, a connecting network for enabling a connection between the gaming console and the gaming service provider, wherein a gaming client is stored in the at least a storage medium of the gaming console, the gaming client for establishing a connection between the gaming console and a gaming service provider and for controlling events taking place on the gaming console; and wherein the configuration of the gaming console is established by the gaming client according to at least one of messages sent to and received from the gaming service provider and messages stored within a personal profile.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] An exemplary embodiment of the present invention will be described in conjunction with the following drawings, in which similar reference numbers designate similar items:
[0011] [0011]FIG. 1 displays a schematic diagram of an on-line gaming architecture;
[0012] [0012]FIG. 2 displays a schematic diagram of an on-line gaming software architecture;
[0013] [0013]FIG. 3 a displays a message sequence chart of an auto-versioning process for an ultra-thin client;
[0014] [0014]FIG. 3 b displays a message sequence chart of a support process for an ultra-thin client; and
[0015] [0015]FIG. 3 c displays a message sequence chart of a selection process for an ultra-thin client.
DETAILED DESCRIPTION OF THE INVENTION
[0016] The present invention is now described with respect to a specific embodiment thereof, wherein a gaming link architecture G_linkA is used to provide an on-line gaming service, and wherein a certain gaming link protocol G_linkP is used to establish data communication within G_linkA. Of course, the invention described herein is not restricted to a particular example, which will be described in what follows, but equally applies to other architectures possibly used to establish and provide an on-line gaming scenario.
[0017] Referring to FIG. 1, a schematic diagram of the gaming link architecture G_linkA for providing an on-line gaming environment is presented. The main components of G_linkA are a customer site containing customer located equipment CLE 110 , a provider site containing provider located equipment PLE 120 , and an access aggregation network AAN 130 connecting CLE 110 with PLE 120 . The customer located equipment CLE 110 includes a gaming console GC 111 and other hardware components necessary for playing a game, such as a monitor, joysticks, and the like, and a modem such as a broad band modem 112 for establishing the connection to the AAN 130 . On the PLE site 120 there is located a gaming service provider network GSP 121 , a management network 122 consisting of multi-service operator's operations support systems MSO-OSS 123 , a router 123 and a head-end 124 , establishing the connection to the ANN 130 , among other components. The access aggregation network ANN 130 generally is a wide area network WNA, and preferably a broadband access network BAN. However, local area networks LAN are also possible solutions for networks providing an on-line gaming service.
[0018] Referring now to FIG. 2, a schematic diagram is shown, illustrating the basic elements of the software architecture used in providing an on-line gaming environment. On the CPE site, the main component is a gaming client G_Client 210 , whereas on the PLE site there is a gaming server G_Server 220 , an operations support services engine G_OSS 230 , a gaming portal G_Portal 240 , and support services G_support 250 .
[0019] The purpose of the gaming client G_Client 210 is to provide the gaming console with services, such as establishing connectivity, registration, and instrumentation. G_Client 210 comprises a registration client, an authentication client, a console address management module, and a module for connectivity and service to a gaming service provider GSP 121 on the PLE site 120 . G_Client 210 supports established methods for data communication and transfer, such as Point-to-Point Protocol PPP, and other recognized data protocols. G_Client 210 checks for connection qualification, and administers bundled instrumentation. According to the embodiment of the present invention, and especially useful in connection with a broadband access network (BAN), a highly functional and adaptive client in form of an ultra-thin client UTC is chosen as the component G_Client 210 . UTC resides on the console in a small segment of random access memory (RAM), thus leveraging a high bandwidth connection to the gaming console, and using it to care and feed the highly functional and adaptive client. In this case, the component G_Client 210 is typically referred to as G_UTC.
[0020] The UTC constitutes a continuously resident, tiny core framework, in which client functionality is partitioned into small code segments, loaded and launched as required at run time. The code segments or packages are small, in general 50 KB or less, and with a broadband bandwidth of about 2 Mbps take milliseconds to load. With UTC, there is no need to maintain state tables; UTC itself becomes a state onto itself, including possible launches from that state. UTC packages are thin, take little space away from the primary function of the GC, and do hardly interfere with the gaming software running on the GC. As a further advantage, the gaming client G_Client 210 becomes very scalable and flexible, and is growing outside the GC without impacting the footprint occupied within the GC. As another advantage, client upgrades and updates are done automatically and in-service, value-added services are simple to include, and individual client services are easier to design and to implement. Also, client code portability between different gaming platforms is highly simplified. This way, G_UTC is a prototypical example for a highly functional client.
[0021] The purpose of the gaming server G_Server 220 is to provide the connectivity and registration services for gaming consoles (GC), and to manage the registered devices. Typically, G Server 220 deals with client registration, subscriber authentication, console address management, as well as Internet protocol (IP) connectivity management and proxy for gaming consoles (GC). G_Server 220 also manages the different GC and different subscribers being part of the on-line gaming architecture G_linkA. Further, G_Server 220 deals with connection qualification, instrumentation and debugging services for consoles, and with bundled instrumentation, and reports facilities for instrumentation, performance and management to G_Client 210 . Although designed as an on-line gaming environment, G_Server 220 enables one to extend the uses of a plurality of gaming consoles (GC) interconnected through a broadband access network beyond gaming and entertainment.
[0022] The purpose of the operations support services engine G_OSS 230 is to provide an application program interface (API) to tie-in with the network service provider's software engines for subscriber authentication, network and policy management, notification, and billing functionalities. G_OSS 230 supports multi-protocol API, containing common utilities with plug-in adapters to facilitate connectivity to a majority of other operating support services (OSS), the plug-in adaptation cartridges supporting Hyper Text Transfer Protocol (http), Simple Network Management Protocol (SNMP), eXtensible Markup Language (XML), JAVA™, OSS/J, and the like. Further, G_OSS 230 handles the task of console-discovery-notification and registration, communicates console to subscriber associations, manages subscriber authentication, and administers connectivity management while addressing state functions such as in-service, suspend, or resume. Also, G_OSS 230 adds, modifies, or deletes a GC or a subscriber to the on-line gaming service, and takes care of billing and service notification, among other related functionalities.
[0023] The purpose of the gaming portal G_Portal 240 is to provide a site for net-based gaming services. It also acts as a proxy site through which net-based game content providers offer content and services to the user of the gaming console GC. G_Portal 240 provides an entry point into the on-line gaming network for game specific servers, for connection servers enabling group gaming, head-to-head services and find-a-friend scheduling, for bulletin boards and chat rooms, as well as for gaming sites and news proxy.
[0024] Optionally, G_Portal 240 offers possibilities such as pay-per-play services, advertising, download services, and others. G_Server 220 also locally offers the same services.
[0025] The system of support services G_support 250 fulfills functions such as running a dynamic host configuration protocol (DHCP), Web servicing, platform and application management, subscriber management, license servicing, and the like. Within the system of support services, there is a dynamic host configuration protocol server G_DHCP 251 , a Web server G_Web 252 dealing with GSP content, GSP data, and GSP instrumentation, as well as a registration server G_Reg 253 .
[0026] G_linkP is used to establish communication within the gaming architecture G_linkA, and is used in supporting the intermodule signaling and control communication and small batch data transfer. G_linkP further enables the use of ultra-thin clients (UTC) for gaming consoles (GC). In the present embodiment of the instant invention, the communication medium is an IP-based, packet protocol, running on IP directly, or on top of a Point-to-Point Protocol (PPP) including PPP use over Ethernet (PPPoE), utilizing XML for external interfaces, and supporting both connected clients via the Transmission Control Protocol (TCP) as well as connectionless clients via the User Datagram Protocol (UDP). Further, G_linkP attempts to keep small messages, typically smaller than the maximum transmission unit (MTU).
[0027] All protocol messages have a common base structure, comprising header, payload, and tail. The header includes information regarding protocol version, message type, control flags, sequence counter, security field, identification of the originating module, identification of the destination module, gaming console class, gaming console vendor, gaming console model, payload size, payload type, and other relevant data characterizing the type and format of the message. The payload contains the main body of the message, comprising any or all of unstructured binary data, structured, formatted data, XML-text-based data, and other interpretable data. Optionally, depending on the message type, the tail comprises a sequence counter, a security field, and/or control flags.
[0028] Typical message types of the gaming link protocol include a logon-message GlP_Hello, a response message GlP_Rsp, a request for download GlP_DReq, an acknowledgment message GlP_ACK, as well as a non-acknowledgement message GlP_NAK, an information package GlP_Info, a data package GlP_Data, and a control package GlP_Control. The main communication between the CLE site 110 and the PLE site 120 over the AAN 130 is handled by the client G_Client 210 and the server services G_Server 220 .
[0029] A boot process of the gaming console GC generally starts an on-line gaming session. First loading the UTC base G_UTC from a compact disc (CD) or from read-only memory (ROM) into random access memory (RAM) initializes a sequence of start-up steps. In this first step, client identification (ID), information regarding the make and the model of the GC, as well as the Internet Protocol (IP) address all are retrieved from RAM.
[0030] Referring now to FIG. 3 a, a message sequence chart (MSC) is shown for an auto-versioning process of the gaming console GC. It is assumed that the client has a valid and authenticated IP address and client ID. The client G_UTC transmits a logon message GlP_Hello to the GSP server G_Server, step 3101 . The logon message contains information regarding the client ID, the version number of G_linkP used, and the like. Next, G_Server is going to validate the client and the protocol used, step 3102 . G_Server looks up the client ID for validity, and decides whether the version of G_linkP is currently supported. In case of an outdated protocol version, a non-acknowledgment message is sent to the client, step 3103 , containing an address and port of updated client software. In a next step, the client requests a proper update, step 3104 , which is followed by the server determining the data for a correct update, step 3105 . The new updated version is determined taking into account new protocol versions, client console class and type, console make and model, and related information. The information is sent to the client G_UTC in form of an acknowledgment message, step 3106 . The client then requests a download for the updated version, step 3107 , transmitting the necessary information such as updated file name and client ID, to the server G_Server. The server G_Server transmits data containing the new UTC version of the client, step 3108 . The auto-versioning procedure is concluded with an upgrade, step 3109 . The new base client UTC is loaded, and an update flag for NVRAM is set. If the new client is successfully activated, and if the update flag is set, the new client is loaded into RAM. Optionally, after being loaded into RAM, the new client is preserved in NVRAM, if it was originally stored in NVRAM. Otherwise, if the update flag is not set, the old base client is reactivated, and the autoconfiguration procedure is repeated.
[0031] Referring now to FIG. 3 b , a message sequence chart (MSC) is shown, how a UTC client is supported by the support services, and especially by G_Server. It is assumed that the client has a valid and authenticated IP address and client ID. It is further assumed that G_UTC is running. The client G_UTC transmits a logon message GlP_hello to the GSP server G_Server, step 3201 . The logon message contains information regarding the client ID, the version number of G_linkP used, and the like. Next, G_Web is going to validate the client and the protocol used, step 3202 . G_Web looks up the client ID for validity, and decides whether the version of G_linkP is currently supported. In case of authenticated information, an acknowledgment message is sent to the client, step 3103 . The client G_UTC then transmits information to the server G_Web, regarding an active element of the client, step 3204 . The active element refers for example to a particular gaming situation of an ongoing interactive computer game, or it possibly refers to information determining gaming characteristics of a certain user, such as information contained in a personal profile. The support server sets a state and a jump table, and updates a client record, step 3205 . This step is based on a current state and transition table of the client, and transition options with prompts and probabilities are determined. These options are sent back to the client as control data, step 3206 . G_UTC then presents a menu to the user, step 3207 . Possible options are different choices within a gaming scenario, different gaming services to be loaded and activated, different gaming qualities, and the like. After the selection is made, the client transmits the corresponding download request, step 3208 , and the server responds by transmitting the corresponding data to the client, step 3209 . Optionally, based on certain probabilities with respect to certain download requests, G_Server chooses to preload one or more selection modules, step 3210 , the modules resulting from a next probable transition taking place on the CLE site. This prefetching process represents a form of caching, which provides the end user with real-time responsiveness.
[0032] Referring now to FIG. 3 c, a message sequence chart (MSC) is shown, for a method of UTC selection. The client G_UTC is running on the GC, and is offering a menu of selections to the subscriber, or to a user on the CLE site, step 3301 . Optionally, one or more than one probable selections are preloaded by G_UTC. The subscriber or user then makes a selection, which corresponds to a transition for G_UTC. G_UTC loads and runs the selected transition, step 3302 . Optionally, when the selection was preloaded, a process of loading the selection is not required. A new state is now loaded and activated. G_UTC stays active as supervisor, and for a return to a main menu, but spawns a selected transition module. The client G_UTC then transmits information to the server G_Server, regarding an active element of the client, step 3303 . The active element refers for example to a particular gaming situation of an ongoing interactive computer game, or it possibly refers to information determining gaming characteristics of a certain user, such as information contained in a personal profile. The support server sets a state and a jump table, and updates a client record, step 3304 . This step is based on a current state and transition table of the client, and transition options with prompts and probabilities are determined. These options are sent back to the client as control data, step 3305 . The client transmits a corresponding download request, step 3306 , and the server responds by transmitting the corresponding data to the client, step 3307 . Optionally, based on certain probabilities with respect to certain download requests, G_Server chooses to preload one or more selection modules, step 3308 , the modules resulting from a next probable transition taking place on the CLE site.
[0033] The above-described procedures illustrate the basic modus operandi of the instant invention, and it is obvious to a person of skill in the art that the presented communication protocols are easily extended to incorporate and fulfill a variety of other functionalities. Besides the described autoconfiguration procedure, the UTC selection step possibly offers a selection of configuration options that are settable and adaptable by the subscriber or by the user. For example, certain gaming requests are excluded from the GC, or are only possible to be activated at a certain point in time, say in the evening after 10 p.m. Selected options are then stored in a personal profile. The selected options include options regarding gaming executed on the gaming console, options regarding parental control issues, and other options. The personal profile is either located on the provider site, associated with a client ID and IP address, and is accessed by the support services when a request from a certain client is registered, or the profile is stored in the NVRAM of the gaming console, and is loaded at boot time. Alternatively, a given personal profile is not associated with a specific IP address, but is associated with a net-mask or a subnet-mask. This way, for example, a complete home is declared as a violence free gaming zone.
[0034] The personal profile is optionally used to protect the GSP from certain legal liabilities. For example, according to a given legislation, the provider of a game, and therefore by extension the GSP, has a liability and/or a responsibility to ensure age appropriate contents. By using the personal profile to determine an age profile of its audience, an appropriate UTC instance is loaded enforcing and allowing only approved age appropriate content. This way, the GSP exercises age control on the services and games provided.
[0035] The same way as the personal profile is used to exercise age control, the personal profile is optionally used to exercise parental control. It is possible for parents to block the access to certain type of games, which for example engage their user in violent actions, confront their users with sexual content, and challenge their user with contents of profanity. This way, it is possible for parents to ensure that their educational measures are not undermined by gaming activities performed by their children in their recreational activities. This way, it is possible for younger audience to safely participate in new forms of social interactions related to online gaming activities. Of course, the concept of parental control as described above is easily extended to other forms of control for designated user groups of a given gaming console (GC).
[0036] The autoconfiguration procedure also allows one to efficiently deal with security issues. G_UTC itself is the distributed key for security, and the possibility to constantly and automatically update G_UTC introduces enough flexibility into the gaming system, to provide a secure gaming environment.
[0037] Although the instant invention has been described with respect to a specific embodiment thereof, various changes and modifications are optionally carried out by those skilled in the art without departing from the scope of the invention. Therefore, it is intended that the instant invention encompass such changes and modifications as fall within the scope of the appended claims. | An interactive gaming system comprising a gaming console and a gaming service provider is disclosed. The gaming console contains a storage medium, on which data relating to a configuration of the gaming console are stored. The gaming console further contains a processor in communication with the storage medium for retrieving data therefrom and executing the data, the data relating to the configuration of the gaming console. A gaming service provider provides instruction data to the gaming console, and a connecting network enables a connection between the gaming console and the gaming service provider. Further, a gaming client is stored on the gaming console. The gaming client establishes a connection between the gaming console and a gaming service provider and controls events taking place on the gaming console. The configuration of the gaming console is established by the gaming client according to messages sent to and received from the gaming service provider and to messages stored within a personal profile. | 0 |
CROSS-REFERENCES TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. §1.19 (e) to, and hereby incorporates by reference, U.S. Provisional Application No. 61/009,544, filed Dec. 27, 2007.
BACKGROUND OF THE INVENTION
Peroxy compounds such as hydrogen peroxide, sodium perborate, sodium percarbonate, sodium persulfate, sodium perphosphate, peroxyacetic acid and numerous organic peroxides are well known for their ability to release peroxide in solution, which is useful for bleaching stains in laundry, food handling areas, and other industrial and institutional applications. These compounds can also exhibit antimicrobial properties. While solutions of these compounds exhibit these properties, many stains and microbes resist the effect of peroxide and are therefore ineffective in some situations.
Adding a bleach activator to peroxy compounds will enhance the effectiveness of the peroxy species to improve the bleaching and antimicrobial properties of the peroxy compound.
The standard in the industry for bleach activators is tetraacetylethylenediamine (“TAED”). TAED is commonly used to enhance the cleaning and bleaching effectiveness of peroxy compounds and is a component of many powdered and solid products. It is, however, only used in the form that it is supplied from the manufacturers, that is, the powdered or granular form. In the solid powdered or granular form TAED cannot be pumped by a liquid dispensing system, which is most commonly used in industrial and institutional laundry operations and in destaining items in food handling areas. This limitation greatly limits the usefulness of TAED. If an activator such as TAED could be pumped to its location of use, it would greatly enhance the effectiveness of peroxy bleaches in industrial and institutional use.
Safety, savings and environmental benefits would be therefore achieved if TAED could be added as a liquid through an automatic dispensing system.
SUMMARY OF THE INVENTION
There is provided a method of treating a fabric, the method comprising using an effective amount of a two component system, the two component system comprising a peroxy compound and a liquid peroxy bleach activator. The peroxy compound and the peroxy bleach activator may be mixed to form an activated peroxy bleaching system. The method may further include immersing the fabric in a wash solution containing the bleaching system. The peroxy compound may comprise a peroxy bleach. The peroxy bleach may include a peroxide, a perborate, a percarbonate, a persulfate, a perphosphate, a peracetic acid, or a benzoyl peroxide. The peroxy activator may include a liquid aqueous solution, which may be a solution, a slurry or a suspension. Application of the peroxy activator may improve the bleaching, cleaning, or antimicrobial effectiveness over the use of the peroxy compound alone. The peroxy activator may include tetraacetylethylenediamine (TAED). The TAED may be fluidized and may be solubilized in water by adding an alkaline material to a water-TAED mixture. The source of alkalinity may be a hydroxide of lithium, sodium, potassium, magnesium, or calcium, or may be an ammonium ion. The liquid peroxy bleach activator may include between about 60.0% and 99.8% water by weight, 0.1% and 20% TAED by weight, and/or 0.1% and 20% liquid NaOH by weight. The peroxy compound may be in a liquid, dry, or powdered form. The peroxy compound may also include hydrogen peroxide, optionally present in a concentration between about 1% and 50% by weight, between about 10% and 35% by weight, or between about 20% and 35% by weight.
There is also provided a method of treating a hard surface by mixing a peroxy bleach with a liquid bleach activator at the time of use in applying a resulting solution to the surface to be claimed.
There is further provided a liquid peroxy bleach activator, comprising TAED dissolved in an alkaline aqueous solution. The bleach activator may comprise between about 60% and 99.8% water by weight, between about 0.1% and 20% TAED by weight, and between about 0.1% and 20% dissolved alkaline substance by weight. The alkaline substance may comprise an ammonium ion or a hydroxide of lithium, sodium, potassium, magnesium, or calcium.
DETAILED DESCRIPTION OF THE INVENTION
This invention provides a liquid peroxy activator which can be mixed with a source of peroxy bleach such that the liquid activator can be pumped through a dispensing system at the time of use.
One of the components of this invention is a peroxy containing compound including, but not limited to, hydrogen peroxide, sodium perborate, sodium percarbonate, sodium persulfate, sodium perphosphate, benzoyl peroxide or any organic (i.e., carbon-containing) peroxy compound that releases oxygen when in aqueous solution. While hydrogen peroxide is supplied as an aqueous liquid in standard concentrations up to nominally 50% active, the other peroxy compounds may be dissolved or suspended in water to provide a peroxy species in a pumpable solution/suspension. Now in a liquid form, the peroxy solution/suspension can be automatically added via a dispensing device.
The second component of this invention is a bleach activator, previously defined as any compound added to a peroxy solution to increase its effectiveness. Typical use conditions for effective use of peroxy bleaches can be as high as 190 degrees F and a pH of 12 or higher. Using an activator of this invention allows the use conditions to be less aggressive, i.e., below 150 deg. F and pH levels below 11.0 yet obtaining equal results compared to bleaching with peroxide alone or with sodium hypochlorite. Washing and bleaching in milder conditions saves energy, is less harmful to the objects being cleaned and provides a safer environment for workers.
The most commonly used peroxy bleach activator is TAED. TAED is commercially available only in powdered form and cannot be, therefore, pumped automatically into its final use application. TAED is found in powdered in solid detergents, usually being co-mixed together with a dry peroxy compound. Having the two powdered/granular forms of both components in one product differs from the present invention in that, in the present invention, the bleach activator is available in a liquid form so it can be pumped into a washing machine, reservoir, or spray device as two separate distinct products.
The difficulty overcome by this invention is that TAED is only slightly soluble in water and other liquids that would be acceptable for use in cleaning solutions. I have found the solubility of TAED can be greatly increased by adding an alkaline substance to the water/TAED solution. In doing so, the concentration of TAED can be increased to over 20% by weight in an aqueous solution. The preferred alkaline materials include, but are not limited to, the hydroxides of lithium, sodium, potassium, magnesium, or calcium or to the ammonium ion.
Example 1
The procedure for the manufacture of one embodiment of the concentrated TAED solution of this invention introduced 60% by weight water into a mixing vessel, added 20% by weight TAED powder/granular material with good agitation, then 20% by weight sodium hydroxide (50% liquid as supplied) was added, the contents of the vessel were then mixed and mixing until the TAED dissolved into a clear to slightly hazy solution.
Example 2
A sample of the TAED solution from Example 1 was tested on an actual wash load of linens. The washing machine was a 50 lb capacity front-loading commercial type washing machine. During the bleaching cycle 2 oz of hydrogen peroxide and 0.5 oz of the TAED solution were added to the bleaching cycle. After the wash cycle was complete, the linens were examined for stain removal. This system was found to be as effective as peroxide bleaching and hypochlorite bleaching at higher temperatures and pH's.
Example 3
A liquid slurry of TAED was made by adding granular TAED to water with vigorous agitation to produce a fluid/liquid form of TAED that could also be pumped through a dispensing device to its final use application. While this was not as useful as the true solution of TAED for some applications, it did allow for dispensing, although it required the slurry to be continuously vigorously mixed to prevent TAED granules from settling in the mix vessel.
Example 4
The above solutions of TAED were added to the cycle of the washer of Example 2 through a peristaltic pump, although any suitable pump could have been used.
In larger cleaning operations, it is often the practice to pump cleaning chemicals into a flush system to have the chemicals flushed to the final use area with running water which enables the pumps to be placed at remote locations relative to the final use location. Solutions can also be fed to a cleaning system by gravity as long as the cleaning compounds are fluid and liquid.
Powdered or granular sources of peroxy bleach can be added to a cleaning system with the liquid activator being pumped in as a separate ingredient into the final use application. This would allow for a product to contain a peroxy bleach source that is activated only at the time of use with the liquid activator.
Example 5
Test swatches of 1″×1″ were stained with blood and subjected to bleaching with various ratios of hydrogen peroxide, 35%, to the liquid TAED activator of Example 1. Beneficial results were observed with ratios from 1 part hydrogen peroxide to 5 parts of the TAED solution through a ratio of 20 parts hydrogen peroxide to 1 part TAED solution.
Example 6
Applying a water solution of 1 part hydrogen peroxide to 0.5 parts of the TAED solution of Example 1 was poured onto a coffee stain on a table and effectively removed the stain.
Peracetic acid has been used to effectively treat fabrics for stain removal and antibacterial efficacy. It has significant health hazards involved with such applications. Contact with Peracetic can cause severe and permanent tissue damage and blindness. Use of the current invention overcomes these safety issues in that the hazard is only as severe as the hydrogen peroxide that was previously used but with the increased effectiveness afforded to the cleaning operation. While no more hazardous that hydrogen peroxide it is as effective as peracetic acid in cleaning or bleaching. | A method of treating a fabric using an effective amount of a two component system comprising: i) a source of peroxy bleach; and ii) a source of peroxy bleach activator in liquid form where the two components are mixed at the time and location of use to form an activated peroxy bleaching system. | 3 |
SUMMARY OF THE INVENTION
[0001] An embodiment of the present invention is generally directed to an appliance system that typically includes a food retaining space having a volume within the space; a module removably connectable to an appliance; and at least one compressed gas containing receptacle that includes all or a portion of a modified atmosphere to be added to the food retaining space. The module typically includes a housing, a controlling device, a switch, at least one valve, a vacuum pump, and a gas inlet wherein the switch, the valve, and the vacuum pump are each in communication with the controlling device (typically a microcontroller or a control board in combination with a relay).
[0002] Another embodiment of the present invention includes a method of providing a modified atmosphere to a food storage space having a volume for enhancing the preservation of food stored in the food storage space when the food storage space contains the food and the modified atmosphere. Typically the method includes the steps of: providing a food storage space having a volume within the food storage space, a module removably connectable to an appliance, and at least one compressed gas containing receptacle that includes all or a portion of a modified atmosphere to be added to the food storage space; engaging the food storage space with the module such that gas is allowed to flow into and out of the volume within the food storage space; activating the module to remove ambient gas within the food storage space until a predetermined vacuum level is reached, allowing gas to flow from the compressed gas containing receptacle into the food storage space to thereby create a modified atmosphere within the food storage space; and sealing the modified atmosphere and any food within the food storage space within the food storage space. The module typically includes a housing, a controlling device, a switch, at least one valve, a vacuum pump, and a gas inlet where the switch, the valve, and the vacuum pump are each in communication with the controlling device and where a valve is positioned between the gas inlet and the switch, the food storage space and the vacuum pump such that compressed gas cannot flow past the valve when the valve is in the closed position and compressed gas can flow into the food storage space when the valve is in the open position;
[0003] Yet another embodiment includes an appliance system that includes a food retaining space having a volume within the space; and a module removably connectable to an appliance and at least one compressed gas-containing receptacle. The module typically includes a housing, a controlling device, a switch, at least one valve, a vacuum pump, and a gas inlet. The switch, the valve, and the vacuum pump are typically each in communication with the controlling device and the valve is typically positioned between the gas containing receptacle inlet and the switch, the food retaining space and the vacuum pump such that compressed gas cannot flow past the valve when the valve is in the closed position and compressed gas can flow into the food retaining space when the valve is in the open position. The at least one compressed gas containing receptacle may include a predetermined blend of gases for a given type of food product. The food product is typically a meat product, a dairy product, a fruit product, a vegetable product, and a fish product. The typical modified atmosphere for a meat product contains about 70% by volume oxygen, about 20% by volume carbon dioxide, and about 10% by volume nitrogen. The typical modified atmosphere for a fish product contains about 40% by volume carbon dioxide and about 60% by volume nitrogen. The typical modified atmosphere for fruits or vegetables contains from about 3% to about 10% by volume oxygen, from about 3% to about 10% by volume carbon dioxide, and from about 80% to about 94% by volume nitrogen. The typical modified atmosphere for dairy products contains from about 10% to about 30% by volume carbon dioxide and from about 70% to about 90% by volume nitrogen.
[0004] These and other features, advantages, and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims, and appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is an elevated perspective view of an embodiment of a module of the present invention;
[0006] FIG. 2 is an elevated front view of an embodiment of a module of the present invention;
[0007] FIG. 3 is an elevated rear view of an embodiment of a module of the present invention;
[0008] FIG. 4 is an elevated rear view of an embodiment of a module of the present invention with the rearward cover of the upper portion of the module removed;
[0009] FIG. 5 is an elevated front view of a side-by-side refrigerator/freezer appliance with a module according to an embodiment of the present invention engaged to the inner door liner surface of the refrigerator section of the appliance;
[0010] FIG. 6 is an elevated front view of a side-by-side refrigerator/freezer appliance with a module according to an embodiment of the present invention engaged to the outer door surface of the appliance;
[0011] FIG. 7 is an elevated view of another embodiment of the present invention where the module receives power from the appliance using an electrical umbilical connection between the module and the appliance;
[0012] FIG. 8 is an embodiment of the present invention showing the use of one valve to regulate flow of the gas into and out of the food retaining compartment/space with the valve in the closed position to not allow gas to flow from the gas canister and depicting the gas being removed from the compartment/space;
[0013] FIG. 9 is the embodiment of the present invention shown in FIG. 8 with the valve in the open position with gas from the canister being supplied to the food retaining compartment/space;
[0014] FIG. 10 is the embodiment of the present invention shown in FIGS. 8-9 with a second valve positioned between proximate the vacuum pump and proximate the compressed gas canister showing the system in the ambient gas removal mode;
[0015] FIG. 11 is the embodiment of the present invention shown in FIG. 10 showing the system supplying modified atmosphere to the food retaining compartment/space with the valve proximate the compressed gas in the open position and the valve proximate the vacuum pump in the closed position;
[0016] FIG. 12 is another embodiment of the present invention showing a plurality of gas canisters in the ambient gas removal mode;
[0017] FIG. 13 is another embodiment of the present invention showing multiple compressed gas canisters that can be connected through one inlet to supply the modified atmosphere;
[0018] FIG. 14 shows a pressure v. time curve where the opening time of the modified atmosphere supplying valve (T 2 -T 1 ) depends on the emptying time (T 1 -T 0 ) and is calculated to have only a fraction of atmospheric pressure within the food retaining compartment/space when the modified atmosphere has been supplied to the food retaining compartment/space.
[0019] FIG. 15 shows a pressure v. time curve where the opening time for the valves (T 2 -T 1 ) depends on the emptying time (T 1 -T 0 ) and the valves proximate a plurality of gas canisters (a,b,c) are opened for a calculated time in order to build a predetermined partial pressure of gases that form a predetermined blend of gases that make up a modified atmosphere;
[0020] FIG. 16 shows a flowchart of a system for supplying a modified atmosphere to a rigid food retaining compartment/space according to an embodiment of the present invention; and
[0021] FIG. 17 shows a flowchart of a system for supplying a modified atmosphere to a food retaining bag according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0022] The present invention generally relates to a removably connectable module that forms part of an appliance system. As shown in FIGS. 1-2 , the appliance system typically contains a module 12 capable of forming a modified atmosphere within a food retaining compartment/space that has a volume in an appliance and/or facade or module receiving housing that can sit on a countertop and either be powered using a direct connection or an umbilical-type power connection 11 or electrically connected to a standard electrical socket when the module receiving housing and the module are placed on a countertop or the like. Typically, the appliance 10 is a refrigerator, but conceivably could be any appliance such as a refrigerator and freezer combination, refrigerator, or freezer alone or could also be a refrigerated space that receives cooler air from another source such as a freezer compartment. Most preferably, the appliance contains a refrigerator compartment that has an inner liner. Whether a traditional appliance or a refrigerated space, the appliance typically is capable of providing electrical power to the module when the module is operatively connected to the appliance. Generally speaking, the module operates to evacuate the food retaining compartment/space (typically a container, bag or other compartment/space 14 ). When the food retaining compartment/space is a bag, it may be a heat-sealable bag and the bag may also optionally be either of fixed volume or expandable. When the food retaining compartment/space is a fixed volume container, a fixed geometry container or a fixed volume compartment within the module, the compartment typically has one or more valves.
[0023] The modified atmosphere injected into the food containing compartment/space 14 extends the freshness of refrigerated food. The atmosphere selected is customizable so that it best extends the life of the food or food group that the consumer wishes to extend the life thereof.
[0024] The modified atmosphere module generally includes a housing 16 and a control device 18 typically positioned within the housing. The housing typically contains an upper portion 20 and a lower portion 22 with the control device typically contained within the upper portion 20 of the housing 16 as well as two sides 24 , a bottom surface 26 and a top surface 28 . The sides typically have at least one, more typically a plurality, substantially T-shaped appliance-receiving groove 30 that is formed by a raised substantially T-shaped portion 32 along the perimeter of the groove 30 . This configuration operates by engaging mating elements of the appliance to retain the module in engagement with the appliance, usually along the liner of the appliance or other chamber of the appliance. Typically, the module engages the inner surface of the liner of the appliance 34 and the mating elements of the appliance are along the inward facing surfaces 36 of the liner mutually facing one another. Typically, the module is held in engagement with the appliance at least partially, more typically substantially or entirely by pressure fit between the inward facing surfaces of the appliance and the sides of the module.
[0025] Typically, the upper portion of the module has at least one snap release receiving groove 38 along the sides of the module for receiving/engaging a push button snap release element 40 of a covering component 42 that may optionally contain a control panel 44 or be configured to allow access to a control panel that is a part of the module through an aperture/window 46 (typically along the user facing surface of the module) when the covering component is engaged to the upper portion of the module. The covering is held in place at least partially by at least one biased component, but more typically two or more biased components 39 that frictionally engage the covering component, typically along the sides. Usually, the covering component contains at least one cover appendage 48 along each side of the covering component that operatively connects/engages upwardly extending cover receiving grooves 50 along the sides of the upper portion of the module.
[0026] Typically, the front/user facing surface of the lower portion of the module is solid and typically will contain a projection portion 52 that also forms a recessed portion 54 in the opposite rearward facing side of the module. The lower portion of the module also typically contains a user removable gas canister cover 56 that covers the gas canister(s) or receptacles from view when the canister engages with the gas-canister receiving inlet. The lower portion of the module also typically incorporates a user-facing tray 59 that is typically capable of supporting the food retaining compartment/space with or without food within the compartment. The tray also typically contains an optionally removable lattice structure 60 to allow small food components to fall between the spaces in the gridwork. Typically the lattice structure is sized to fit within the entire tray but conceivably only a portion of the tray may include a lattice structure and the remainder of the tray may be flat and smooth or the tray could be entirely flat and smooth. Also, the tray could be textured to provide a slip resistant surface.
[0027] As can be seen in FIGS. 3-4 , the rearward facing surface of the module typically contains an upper portion rearward-side cover 62 that covers the main operating elements of the module contained within the upper portion of the module. The rearward-side cover 62 is typically held in place with at least one, more typically a plurality of fasteners such as screws 64 . Typically the rearward side of the upper portion also has an appliance/power connector 66 that receives the connection from the appliance or other power source for the electrical power of the module.
[0028] As shown in FIG. 4 , the upper portion of the module typically contains or is proximate at least one gas receiving inlet 68 . The gas receiving inlet is typically spaced just within the lower portion of the module to allow easy connection of the canister through a typically circular aperture in the dividing wall 70 between the upper portion and the lower portion of the module. Conceivably, a plurality of gas receiving inlets/connections can be utilized to receive a variety of different gas canisters. The gas canisters typically have a volume of about one liter or less. The gas canisters and inlet(s) may be configured such that the gas canisters will only release gas when engaged to an inlet of the module without damaging the canister. The canisters and/or inlet may be configured such that when the canister(s) is(are) operatively connected to the inlet, the control device senses the type of gas contained within the canister. The module is also able to estimate or measure the amount of gas remaining in the canister that is connected to the inlet. The gas canisters may contain one of many different types of gases used to create a final modified atmosphere or may contain a mixture of gases preblended to form a given modified atmosphere that best extends the life of a given food product. It is also possible that the gas canister will contain a single gas that is the only gas used to create the modified atmosphere.
[0029] Typically, the gas proceeds through the inlet and then through a pressure reducer 72 when gas is being supplied to the module. The pressure reducer is typically engaged with the upper portion of the module or held in place using a substantially C-shaped retainer 80 with two flat surfaces 82 . The two flat surfaces typically each receive at least one fastener, typically a screw, which also engages the upper portion of the housing of the module on the interior surface. The upper portion also typically contains one or more valves 74 that are typically solenoid valves as well as a vacuum pump 76 . A substantially C-shaped vacuum pump bracket 86 with two substantially flat ledges retains the vacuum pump within the housing using fasteners, typically screws that engage the vacuum pump bracket and the housing. Optionally, a second vacuum pump stabilizing bracket 88 can be used to further stabilize the vacuum pump within the housing. Tubing 78 capable of having gas move within it typically is used to distribute the gases and may be interconnected using connectors and/or one or more T-junction connectors 84 . Typically, electrical wiring is used to distribute power to the electrically powered elements of the module, including the solenoid valves, the control device, and the vacuum pump.
[0030] The upper portion of the module also typically contains at least one control device that is typically a control board in combination with a relay or a microcontroller. A microcontroller is a functional computer system on a chip that typically contains a processor core, memory, and programmable input/output peripherals. The memory may be RAM, program memory or both. The control device is typically connected with an input receiving device for receiving instructions from a user. Typically the input from the user in the case of the module of the present invention is a control panel with push button or touch sensitive controls. The input receiving device is configured to receive input from the user including what type of modified atmosphere is desired. The control device is configured to be responsive to input from the user that instructs the control device to perform steps based at least in part upon the user input. The control device typically operates to control various other components of the module including the vacuum pump and the opening and closing of the valves. The control device, in the case of a microcontroller, typically has memory that utilizes a calibration curve for estimating the free volume in a container based upon the time necessary to remove ambient air in the food retaining space to a predetermined level at least substantially below ambient pressure and also based upon one or more characteristics of the vacuum pump (for example, the vacuum pump's strength). Typically, the calibration curve is stored in the memory of the microcontroller. In this manner, the control device can approximate when to turn off the vacuum pump and begin to supply modified atmosphere to the food retaining compartment/space.
[0031] Also, optionally, the module may contain one or more gas storage chambers typically within the module where the gas storage chamber(s) are operably connected to the food retaining compartment/space and the chamber(s) can be filled from individual corresponding inlets that receive a gas canister or can be filled through the use of one inlet and valves, typically solenoid valves positioned outside each chamber such that one or more specified gas storage chambers are filled at a given time from the gas canisters. The gas storage chamber could be used to supply all or a portion of the modified atmosphere to the food retaining compartment/space. When only a portion is supplied, the remainder of a given gas for the modified atmosphere can be supplied from the gas canister engaged to the inlet.
[0032] The module may also contain a heat-sealing element, which operates to seal the bag, including a flexible bag when such bags are used at a food storage compartment/space. When utilized, the heat sealing element can be positioned where most convenient to the user, typically in the upper portion of the module and accessible to the user, more typically along the front surface of the module and accessible to the user.
[0033] The module can also contain one or more sensors or switches. These devices can be used to measure and/or detect when the desired pressure level is reached inside the food retaining compartment/space. In one embodiment, a pressure senor can be used to measure the pressure produced as a result of the gas or gases being filled into the food retaining compartment/space. Even in the case of different gases, the sensor can monitor the pressure contribution of each gas filled in sequence (see FIGS. 14-15 ). Another alternative is to use one or more pressure switches to detect when, during the modified atmosphere injection process, the pressure rises to the appropriate level in the food retaining compartment/space and stop the process. This is typically achieved through the use of at least two pressure switches, but could use one pressure switch that uses the hysteresis of the first switch to detect when to stop/start the process. Also, a standard switch can be utilized to estimate the free volume in the food retaining compartment/space. In this instance, the time to empty or substantially empty the food retaining compartment is measured by the control device, typically a microcontroller. The microcontroller typically uses a calibration curve (container free volume vs. emptying time) for the specific vacuum pump being utilized in the module to determine the container free volume and therefore the amount of time to allow modified gas or mixture of gases to flow into the container to prepare the modified atmosphere at a predetermined pressure level. The sensor could also be a light or other optical sensor used to regulate the amount of the modified atmosphere by measuring, for example, the characteristics of how much light is allowed to reach the sensor and/or how light is deflected
[0034] As shown in FIGS. 14-15 , switching on the vacuum pump at the time T 0 , the container starts to empty at a decreasing rate because less gas is extracted by the pump over time. After time T 1 -T 0 , which depends on the volume of the food retaining compartment/space, the pressure reaches the predetermined vacuum level P 1 . The microcontroller can use this time (T 1 -T 0 ) to estimate the free volume inside the food retaining compartment/space using the calibration curve. It is then possible to calculate the amount of gas required to achieve the target pressure P 2 . Typically, this is done by the microcontroller, which communicates with the solenoid valve and the solenoid valve opens to allow gas flow from the gas storage chamber and/or gas canister. Similarly, the above can be used when various bottles of gases are used to fill the food retaining container/space, which is typically the case when multiple canisters of different gas as opposed to a canister with a predetermined blend of different gases is used to create the modified atmosphere. In such a case, more than one valve (three valves a, b, and c are shown in FIG. 15 ) are opened for a time interval corresponding to the amount of gas needed to form the modified atmosphere. The valves are typically opened independently in order to have the required gas mixture inside the container. T 2a -T 1 is the opening time for the first valve, T 2b -T 2a is the opening time of the second valve, T 2c -T 2b is the opening time for the third valve in FIG. 15 . When forming the modified atmosphere it is typically desirable to keep the final modified atmosphere pressure less then atmospheric pressure to ensure the automatic sealing of the food retaining compartment/space. Typically, the final modified atmosphere pressure is about ½ atmospheric pressure or about ½ atmospheric pressure or less.
[0035] The modified atmospheres for use over food products according to an embodiment of the present invention include a modified atmosphere for a meat product, a dairy product, a fruit product, a vegetable product and a fish product. The modified atmosphere may be either oxygen rich or have a reduced oxygen content compared to ambient air. Also, the modified atmospheres of the present invention also typically operate to reduce both aerobic and anaerobic pathogens in the food stored under the modified atmosphere. The modified atmosphere for the meat product typically contains about 70% by volume oxygen, about 20% by volume carbon dioxide, and about 10% by volume nitrogen. The modified atmosphere for the fish product typically contains about 40% by volume carbon dioxide and about 60% by volume nitrogen. The modified atmosphere for fruits or vegetables typically contains from about 3% to about 10% by volume oxygen, from about 3% to about 10% by volume carbon dioxide, and from about 80% to about 94% by volume nitrogen. The modified atmosphere for dairy products typically contains from about 10% to about 30% by volume carbon dioxide and from about 70% to about 90% by volume nitrogen. Applicants also believe that a modified atmosphere can be used for medications. For example, medications that might be prone to oxidation might have their shelf life improved by being stored in a container with a modified atmosphere with reduced oxygen content to prevent or retard oxidation. The modified atmosphere is typically over the medication.
[0036] A method of producing a modified atmosphere within a rigid container typically includes the steps shown in FIG. 16 and described below. First, a food to be stored under a modified atmosphere is placed within the container. Next, the rigid container is engaged to the modified atmosphere module. This can be by a screw-type engagement with the lid of the container or by other sealing type arrangement. Typically, a rigid container uses at least one valve to allow gas flow into and out of the container. Next, the user activates the module by pressing the “start” button on the control panel, which is typically located on the front of the module. The control device, a control board with a relay or a microcontroller, then switches on the vacuum pump and solenoid valve to allow gas to flow out of the container. Typically, a pressure switch detects the pressure level inside the container. When the pressure level reaches a level at or below at least about 500 mBar, the pressure switch sends a signal to the control device and the control device records the vacuum time and turns off the vacuum pump and solenoid valve. Next, the control device switches the solenoid valve blocking the flow of gas from the compressed gas cylinder into the open position and the gas or gas mixture is allowed to flow into the container. Typically, the gas is a gas mixture of preblended gas for a given modified atmosphere that is desired. The control board then switches off the solenoid valve after a time interval depending on vacuum time. Optionally, multiple vacuum and gas injection process can be used to obtain the desired gas composition inside the container. Finally, the container that has the modified atmosphere is sealed and removed from engagement with the module.
[0037] A method of producing a modified atmosphere within a (flexible) bag container typically includes the steps shown in FIG. 17 and described below. The bag is attached to the module and the user pushes the “start” button. The control device switches on the vacuum pump and the solenoid valve thereby allowing gas to flow out of the bag. The vacuum pump pulls the gas from within the bag. When the pressure level reaches a level at or below at least about 500 mBar, the pressure switch sends a signal to the control device and turns off the vacuum pump and solenoid valve. Next, the control device switches the solenoid valve blocking the flow of gas from the compressed gas cylinder into the open position and the gas or gas mixture is allowed to flow into the bag. Typically, the gas is a gas mixture of preblended gas for a given modified atmosphere that is desired. Optionally, multiple vacuum and gas injection processes can be used to obtain the desired gas composition inside the bag. The control board then switches off the solenoid valve after about 5 seconds. Next, the control device typically turns on the heat sealer for about 7 seconds or for such time as necessary to form an air tight seal on the bag. Finally, the container that has the modified atmosphere is removed from engagement with the modified atmosphere module.
[0038] While a vacuum pump is typically used to draw ambient gas from within the food retaining compartment/space and the gas forming the modified atmosphere thereafter added to the food retaining compartment/space, it is also possible to form a modified atmosphere according to another embodiment of the present invention by using overpressure of modified atmosphere to force out the amount of ambient gas and replace this ambient gas with the modified atmosphere.
[0039] In another aspect of the present invention, the present invention includes a kit that typically includes at least: (1) at least one gas canister containing a gas or a blend of gases where the gas canister is capable of engaging a mounting location of a module and wherein the module is capable of being mounted to an inner liner of an appliance containing a refrigerator space and the appliance provides electrical power to the module and the module uses the gas or blend of gases from the canister to provide a modified atmosphere to food contained within a food retaining space that is re-sealably air tight; and (2) instructions that are transmitted to the user of the gas canister or canisters to engage the gas canister with the mounting location of the module. The instructions can be transmitted along with the gas canister or canisters or via a network of computers such as the Internet via a web site or web page hosted on a computer server accessible over the Internet. Also, as discussed above, the canister(s) can be constructed with an engagement outlet that will only allow air flow from the canister without damaging the canister when the canister is connected with the inlet of the module.
[0040] The above description is considered that of the preferred embodiments only. Modifications of the invention will occur to those skilled in the art and to those who make or use the invention. Therefore, it is understood that the embodiments shown in the drawings and described above are merely for illustrative purposes and not intended to limit the scope of the invention, which is defined by the following claims as interpreted according to the principles of patent law, including the Doctrine of Equivalents. | An appliance system including a module removably mounted to an appliance, one or more removable gas canisters operably connected to the module, and a food retaining enclosed space operably connected to the module. The one or more gas canisters supply a modified atmosphere in the food retaining enclosed space to produce a modified atmosphere that enhances preservation of the food contained in the food retaining enclosed space. A method of modifying the atmosphere in a food storage space for food includes the steps of: providing a module capable of being removably engaged to an appliance and typically receiving power from the appliance and at least one removable gas canister; operatively connecting or otherwise engaging the module with the appliance; operatively connecting or otherwise engaging the module to a food storage area having an existing atmosphere; and removing at least a portion of the existing atmosphere from the food storage space and replacing it with a modified food storage atmosphere using at least one of the at least one removable gas canisters to supply the modified atmosphere to the food storage area. | 5 |
This is a continuation application of U.S. Ser. No. 09/649,960 filed Aug. 29, 2000, which is a continuation application of U.S. Ser. No. 09/073,857, filed on May 7, 1998, now U.S. Pat. No. 6,172,986.
BACKGROUND OF THE INVENTION
This invention relates to a mobile node, a mobile agent and a network system. More particularly, this invention relates to a control method which assists the movement of a node between an IP (Internet Protocol) network capable of executing communication in accordance with both IP version 4 and an IP version 6 and an IP network capable of executing communication in accordance with only the IP version 4 or an IP network capable of executing communication in accordance with only the IP version 6, a mobile agent, and a network system for assisting the movement of the node.
With a drastic development of small and light-weight nodes and the Internet, the demand for taking out a node from an office or a home to utilize it everywhere has been increased. When the node is moved to other network in the conventional network environment making use of the TCP/IP (Transmission Control Protocol/Internet Protocol), however, setting of the IP address, which is the information for primarily identifying the node in the IP network, must be changed so as to match with the foreign or visiting network environment.
Even if this change of setting of the IP address is automatically mae by utilizing a DHCP (Dynamic Host Configuration Protocol) described in RFC (Request For Comment) 1541 as one of the methods of distributing automatically the IP addresses, there remains the problem that the network connection that has been established already with other nodes by using the IP addresses used in the network before the movement cannot be maintained in succession.
Therefore, methods of assisting the movement of the node between the networks have been devised. A typical among them is a protocol of the third layer (network layer) of an OSI (Open Systems Interconnection) reference model and this protocol pertains to the IP version 4 (hereinafter called the “IPv4”) that has gained a wide application in the Internet and the IP version 6 (hereinafter called the “IPv6”) the specification of which has now been stipulated so as to solve the problems of address exhaustion in the IPv4. As to these IPv4 and IPv6, “IP Mobility Support in IPv4”) (hereinafter called “Mobile IPv4”) described in RFC2002 and “Mobility Support in IPv6”) (hereinafter called “Mobile IPv6”) described in IETF (Internet Engineering Task Force) draft (the latest version of which is “draft-ietf-mobile-ip-ipv6-02.txt”) are examples of the known references.
Incidentally, the term “IPv4” used in this specification designates an IP address having an address length of 32 bits while the term “IPv6” designates an IP address having an address length greater than 32 bits.
By making use of these Mobile IPv4 and Mobile IPv6, a user can execute communication in the same way before the movement of the node even when the node is moved to another network, without the necessity for changing the IP address of the node or cutting off the network connection that has already been established with other node before the movement.
Incidentally, the term “node” used in this specification designates all those devices which have an IP address and execute communication by utilizing the IP, such as a PC (Personal Computer), a WS (Work Station), a router, and so forth.
Generally, it is assumed that the movement from the IPv4 to the IPv6 is effected gradually and all the networks do not utilize at once the IPv6. In the mean time, therefore, there exist a network (herein-after called the “IPv4 network”) comprising only those nodes which execute communication by utilizing only the IPv4 (hereinafter called the “IPv4 nodes”), a network (herein-after called the “IPv6 network”) comprising only those nodes which execute communication by utilizing only the IPv6 (hereinafter called the “IPv6 node”) and a network (hereinafter called the “IPv4/v6 network”) comprising those nodes which execute communication by utilizing both of IPv4 and IPv6 in mixture (hereinafter called the “IPv4/v6 node”), the IPv4 nodes and the IPv6 nodes.
To beginning with, let's consider the case where the IPv4/v6 network is the one that supports both of Mobile IPv4 and Mobile IPv6. In the Mobile IPv4, messages are exchanged between a mobile node moving between the networks and a mobile agent (herein-after called the “IPv4 mobile agent”) for assisting the movement of the mobile node which executes communication by utilizing the IPv4, in accordance with the Mobile IPv4 procedures. Similarly, in the Mobile IPv6, messages are exchanged between a mobile node moving between the networks and a mobile agent (hereinafter called the “IPv6 mobile agent”) for assisting the movement of the mobile node that executes communication by utilizing the IPv6, in accordance with the Mobile IPv6 procedures.
Let's consider the case where the IPv4/v6 mobile node supporting both of Mobile IPv4 and Mobile IPv6 inside the IPv4/v6 network moves to another IPv4/v6 network. Because the foreign IPv4/v6 network can execute communication by utilizing both of IPv4 and IPv6, the IPv4/v6 mobile node can exchange the messages with both of the IPv4 mobile agent and the IPv6 mobile agent on the network in accordance with the procedures of the Mobile IPv4 and the Mobile IPv6. Therefore, the movement of this IPv4/v6 mobile node between the networks is supported by both of the Mobile IPv4 and the Mobile IPv6. In consequence, the IPv4/v6 mobile node that has moved to the foreign network can successively execute communication without changing setting of the IP address and without cutting off the network connection that has been established already with other IPv4 node or the IPv6 node before its movement by utilizing the IPv4 or IPv6. It can also execute afresh communication with other node by utilizing the IPv4 and the IPv6.
Next, let's consider the case where the IPv4/v6 mobile node moves from the IPv4/v6 network to the IPv4 network which can execute communication in accordance with only the IPv4 and supports the Mobile IPv4. In this case, since communication by utilizing the IPv4 is possible between the IPv4/v6 mobile node and the IPv4 mobile agent, the assistance of movement of this mobile node between the networks by the Mobile IPv4 can be made. Therefore, the IPv4/v6 mobile node can execute communication successively after the movement without cutting off the network connection that has been previously established already with other IPv4 node by utilizing the IPv4. The mobile node can also execute communication afresh by utilizing the IPv4.
However, the mobile node cannot execute communication by utilizing the IPv6 on the IPv4 network and consequently, the exchange of the message on the IPv4 network in accordance with the Mobile IPv6 procedure becomes impossible between the IPv4/v6 mobile node and the IPv6 mobile agent. In other words, the assistance of the movement of the mobile node to the IPv4 network in accordance with the Mobile IPv6 becomes impossible and the IPv4/v6 mobile node that has moved to the IPv4 network cannot maintain the network that has been established already with other IPv6 node by utilizing the IPv6 before the movement and consequently, cannot execute communication. This mobile node cannot execute afresh communication with other node on the IPv4 network by utilizing the IPv6, either.
Similarly, let's consider the case where the IPv4/v6 mobile node moves from the IPv4/v6 network to the IPv6 network which can execute communication by utilizing only the IPv6 and supports the Mobile IPv6. In this case, too, the IPv4/v6 mobile node cannot execute communication by utilizing the IPv4 on the IPv6 network. In consequence, the exchange of the message in accordance with the Mobile IPv4 procedure is not possible on the IPv6 network between the IPv4/v6 mobile agent and the IPv4 mobile agent, so that the assistance of the movement of this mobile node to the IPv6 network in accordance with the Mobile IPv4 becomes impossible on the IPv6 network.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a mobile node, a mobile agent and a network system which can successively maintain the network connection the IPv6 that has been established already by utilizing the IPv6 before the movement when the IPv4/v6 mobile node moves from the IPv4/v6 network to the IPv4 network, and which can also execute afresh communication by utilizing the IPv6.
It is another object of the present invention to provide a control method of a mobile node, a mobile agent and a network system for assisting the movement, which can execute communication by utilizing the IPv4 between an IPv4/v6 mobile node and other IPv4 node even when the IPv4/v6 mobile node moves from an IPv4/v6 network to an IPv6 network, without changing at all existing IPv6 mobile agents and existing IPv4/v6 mobile agents and without changing setting of the address of the IPv4/v6 mobile node.
According to one aspect of the present invention, there is provided a mobile node including IPv4 (Internet Protocol version 4) processing means for executing services in accordance with the IPv4, IPv6 (Internet Protocol version 6) processing means for executing services in accordance with the IPv6, and communication processing means for executing transmission/reception control of packets to and from networks, and moving between IP networks, wherein the mobile node further comprises movement registration processing means for adding an IPv4 header (IP header used for the IPv4), in which the IPv4 address of a mobile agent is set as a foreign address and the IPv4 address of the mobile node usable in a foreign IPv4 network is set as a home address, to a message used for the IPv6 for registering the movement to a mobile agent connected to the IPv4/v6 network to assist the movement of the mobile node, and transmitting the message, when this mobile node moves from the IPv4/v6 network (a network capable of executing communication by utilizing both of the IPv4 and the IPv6) to an IPv4 network (a network capable of executing communication by utilizing only the IPv4).
In the mobile node according to the aspect of the invention described above, the IPv4 header is added to the message used for the IPv6 and the message is then transmitted. Therefore, the message to be used for the IPv6 can be substantially transmitted from the foreign IPv4 network, and the information necessary for the network connection utilizing the IPv6 can be registered to the mobile agent.
According to another aspect of the present invention, there is provided a mobile agent including IPv4 processing means for executing services in accordance with an IPv4, IPv6 processing means for executing services in accordance with an IPv6 and communication processing means for executing transmission/reception control of packets to and from networks, and moving between the networks, wherein the mobile agent further comprises packet transmission processing means for generating an IPv4 encapsulated IPv6 packet by adding an IPv4 header, in which the IPv4 address of the mobile agent is set as a foreign address and the IPv4 address of a mobile node usable in a foreign IPv4 network is set as a home address, to an IPv6 packet (packet used for the IPv6) to be transmitted to other node, and transmitting the IPv4 encapsulated IPv6 packet so generated.
In the mobile agent according to the aspect of the invention described above, after the IPv4 header is added to the IPv6 packet, the packet is transmitted. Therefore, the IPv6 packet can be transmitted substantially from the foreign IPv4 network.
According to still another aspect of the present invention, there is provided a mobile node including IPv4 processing means for executing services in accordance with the IPv4, IPv6 processing means for executing services in accordance with the IPv6 and communication processing means for executing transmission/reception control of packets to and from networks, and moving between the networks, wherein the mobile node further comprises movement detection means for detecting whether the mobile node has moved from the network in which a mobile agent used by this mobile node exists to another IPv4 network or to an IPv6 network (network capable of executing communication by utilizing only the IPv6) or to an IPv4/v6 network, and movement status management means far managing the movement status so detected.
Since the mobile node according to this aspect of the invention automatically detects the kind of the network in which the mobile node itself exists at present and manages itself, the necessity for adding an IPv4 header to the message used for the IPv6 or the IPv6 packet can be judged appropriately.
According to still another aspect of the present invention, there is provided a mobile agent for assisting the movement of a mobile node executing communication by utilizing an IPv6, including IPv4 processing means for executing services in accordance with an IPv4, IPv6 processing means for executing services in accordance with the IPv6 and communication processing means for executing transmission/reception control of packets to and from networks, wherein the mobile agent further comprises mobile node management means for managing the IPv4 address of a mobile node usable in a foreign IPv4 network when receiving a message for use in the IPv6 for registering the movement, to which an IPv4 header transmitted from the mobile node to the IPv6 network to the mobile agent when the mobile agent moves to the IPv4 network is added, and movement assistance processing means for adding an IPv4 header, in which the IPv4 address of the mobile node usable in a foreign IPv4 network is set as a foreign address and the IPv4 address of the mobile agent is set as a home address, to the message used for the IPv6 to permit registration of the movement to the mobile node, and transmitting the message.
In the mobile agent according to the aspect of the invention described above, after the IPv4 header is added to the message used for the IPv6 and then the message is transmitted. Therefore, the message used for the IPv6 can be transmitted substantially to the mobile node that is moving to the IPv4 network.
According to still another aspect of the present invention, there is provided a mobile agent for assisting the movement of a mobile node executing communication by utilizing the IPv6, including IPv4 processing means for executing services in accordance with the IPv4, IPv6 processing means for executing services in accordance with the IPv6 and communication processing means for executing transmission/reception control of packets to and from networks, wherein the mobile agent further comprises transfer-to-other node processing means for deleting the IPv4 header when receiving an IPv4 encapsulated IPv6 packet transmitted by the mobile node, and transmitting again the IP packet so taken out to the network.
In the mobile agent according to the aspect of the invention described above, after only the IPv6 packet is taken out from the IPv4 encapsulated IPv6 packet, the IPv6 is again transmitted. Therefore, the IPv6 packet can be transmitted substantially from the mobile node, that is moving to the IPv4 network, to the node on the IPv6 network or on the IPv4/v6 network.
According to still another aspect of the present invention, there is provided a mobile agent for assisting the movement of a node executing communication by utilizing the IPv6, including IPv4 processing means for executing services in accordance with the IPv4, IPv6 processing means for executing services in accordance with the IPv6 and communication processing means for executing transmission/reception control of packets to and from networks, wherein the mobile agent further comprises transfer-to-other node processing means for generating an IPv4 encapsulated IPv6 packet by adding an IPv4 header, in which the IPv4 address of a foreign node usable in a foreign IPv4 network is set as a foreign IPv4 address and the IPv4 address of the mobile agent is set as a home IPv4 address, to the received IPv6 packet when receiving this IPv6 packet transmitted by other node to the mobile node that has moved to the IPv4 network, and for transmitting this IPv4 encapsulated IPv6 packet.
In the mobile agent according to the aspect of the invention described above, after the IPv4 header is added to the IPv6 packet, the IPv6 packet is transmitted. Therefore, the IPv6 packet can be transmitted substantially from the node on the IPv6 network or on the IPv4/v6 network to the mobile node that is moving to the IPv4 network.
According to still another aspect of the present invention, there is provided a network system in which an IPv4/v6 network and an IPv4 network are connected with each other by a connecting device or by the connection device and a third network, wherein the mobile agent according to the fourth, fifth or sixth aspect is provided on the IPv4/v6 network and the mobile node according to the first, second or third aspect is provided on the IPv4/v6 network or on the IPv4 network.
The network system according to the aspect described above can successively keep the network connection, which utilizes the IPv6 and has been already established before the movement of the IPv4/v6 node, when the IPv4/v6 node moves from the IPv4/v6 network to the IPv4 network, and can execute afresh communication by utilizing the IPv6.
According to still another aspect of the present invention, there is provided a method of controlling a mobile node by a mobile agent in a network system in which a first IP network capable of executing communication in accordance with first and second kinds of IPs and a second IP network capable of executing communication in accordance with only the first kind of IP, so that the mobile node capable of executing communication in accordance with the second kind of IP can communicate with other node belonging to the first IP network in accordance with the second kind of IP when the mobile node moves from the first IP network to the second IP network, which method comprises the steps of adding a first kind of IP header, in which the IP address of a second mobile agent belonging to the second IP network in accordance with the first kind of IP is set as a foreign address by the first mobile agent belonging to the first IP network and the IP address of the first mobile agent in accordance with the first kind of IP is set as a home address, to an IP packet transmitted in accordance with the second kind of IP from other node to the mobile node, and transmitting the IP packet to the second mobile agent; and deleting the first kind of IP header by the second mobile agent and transmitting the IP packet to the mobile node.
On the other hand, the IP packet may be transmitted to other node by adding the first kind of IP header, in which the IP address of the first mobile agent in accordance with the first kind of IP is set as a foreign address by the second mobile agent and the IP address of the second mobile agent in accordance with the first kind of IP is set as a home address, to the IP packet in accordance with the second kind of IP transmitted from the mobile node to other node, transmitting this IP address to the first mobile agent, deleting the first kind of IP header by the first mobile agent and then transmitting the IP packet to other node.
Alternatively, it is possible to employ a method comprising adding the first kind of IP header, in which the IP address of the first mobile agent in accordance with the first kind of IP is set as a foreign address by the second mobile agent and the IP address of the second mobile agent in accordance with the first kind of IP is set as a home address, to a movement registration request message in accordance with the second kind of IP that is received from the mobile node, transmitting this message to the first mobile agent, adding the first kind of IP header, in which the IP address of the second mobile agent in accordance with the first kind of IP is set as a foreign address by the first mobile agent and the IP address of the first mobile agent in accordance with the first kind of IP is set as a home address, to a message in accordance with the second kind of IP for permitting the movement, and transmitting this message to the second mobile agent.
The present invention provides also a network system for assisting the movement of the mobile node, having the features described above.
Furthermore, the present invention provide the first and second mobile agents for assisting the movement of the mobile node, having the features described above.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a structural view of a network system according to one embodiment of the present invention;
FIG. 2 is a structural view of a movement status management table used in an IPv4/v6 mobile node shown in FIG. 1 ;
FIG. 3 is a structural view of a mobile node management table used in an IPv6 mobile agent shown in FIG. 1 ;
FIG. 4 is a flowchart showing an IPv4/v6 movement processing in the IPv4/v6 mobile node shown in FIG. 1 ;
FIG. 5 is a flowchart showing a movement detection processing in the IPv4/v6 shown in FIG. 1 ;
FIG. 6 is a flowchart showing an IPv4 movement registration processing in the IPv4/v6 mobile node shown in FIG. 1 ;
FIG. 7 is a flowchart showing an IPv6 movement registration processing in the IPv4/v6 mobile node shown in FIG. 1 ;
FIG. 8 is a flowchart showing an IPv4-only movement registration processing in the IPv4/v6 mobile node shown in FIG. 1 ;
FIG. 9 is a flowchart showing an IPv6 packet transmission processing in the IPv4/v6 mobile node shown in FIG. 1 ;
FIG. 10 is a flowchart showing an IPv6 movement assistance processing in an IPv6 mobile agent shown in FIG. 1 ;
FIG. 11 is a flowchart showing a transfer-to-mobile node processing in the IPv6 mobile agent shown in FIG. 1 ;
FIG. 12 is a flowchart showing a transfer-to-other node processing in the IPv6 mobile agent shown in FIG. 1 ;
FIG. 13 is a structural view of an IPv6 movement registration request message;
FIG. 14 is a structural view of an IPv4 encapsulated IPv6 movement registration request message;
FIG. 15 is a structural view of an IPv4 encapsulated IPv6 packet;
FIG. 16 is a structural view of an IPv4 encapsulated IPv6 movement registration permission message;
FIG. 17 is a structural view of an IPv6 encapsulated IPv6 packet;
FIG. 18 is a structural view showing an example of a network to which the present invention is applied;
FIG. 19 is an explanatory view showing a structural example of a mobile node management table used in a home IPv6 mobile agent shown in FIG. 18 ;
FIG. 20 is an explanatory view showing a structural example of a mobile agent address table used in a foreign IPv6 mobile agent shown in FIG. 18 ;
FIG. 21 is an explanatory view showing a structural example of a movement assistance management table used in the foreign IPv6 mobile agent shown in FIG. 18 ;
FIG. 22 is an operation flowchart showing an example of the procedure of an IPv4 movement processing in an IPv4/v6 mobile node shown in FIG. 18 ;
FIG. 23 is an operation flowchart showing an example of the procedure of an IPv6 movement processing in the IPv4/v6 mobile node shown in FIG. 18 ;
FIG. 24 is an operation flowchart showing an example of the procedure of an IPv6 movement assistance processing in a home IPv6 mobile agent shown in FIG. 18 ;
FIG. 25 is an operation flowchart showing an example of the procedure of a foreign IPv6 mobile agent shown in FIG. 18 ;
FIG. 26 is an operation flowchart showing an example of the procedure of a transfer-to-foreign IPv6 mobile agent processing in the home IPv6 mobile agent shown in FIG. 18 ;
FIG. 27 is an operation flowchart showing an example of the procedure of a transfer-to-other node processing in the home IPv6 mobile agent shown in FIG. 18 ;
FIG. 28 is an operation flowchart showing an example of the procedure of a transfer-to-home IPv6 mobile agent processing in the foreign IPv6 mobile agent shown in FIG. 18 ;
FIG. 29 is an operation flowchart showing an example of the procedure of a transfer-to-mobile node processing in the foreign IPv6 mobile agent shown in FIG. 18 ;
FIG. 30 is an explanatory view showing a structural example of an IPv6 movement registration request message;
FIG. 31 is an explanatory view showing a structural example of a packet obtained by encapsulating an IPv6 encapsulated IPv6 packet by IPv4 encapsulation;
FIG. 32 is a structural view showing another example of a network to which the present invention is applied;
FIG. 33 is an explanatory view showing a structural example of a mobile node management table used in a home IPv4 mobile agent shown in FIG. 32 ;
FIG. 34 is an explanatory view showing a structural example of a mobile agent address table used in the foreign IPv4 mobile node shown in FIG. 32 ;
FIG. 35 is an explanatory view showing a structural example of a movement assistance management table used in the foreign IPv4 mobile agent shown in FIG. 32 ;
FIG. 36 is an operation flowchart showing an example of the procedure of an IPv4 movement assistance processing in a home IPv4 mobile agent shown in FIG. 32 ;
FIG. 37 is an operation flowchart showing an example of the procedure of the foreign IPv4 movement assistance processing in the foreign IPv4 mobile agent shown in FIG. 32 ;
FIG. 38 is an operation flowchart showing an example of the procedure of a transfer-to-foreign IPv4 mobile agent processing in a home IPv4 mobile agent shown in FIG. 32 ;
FIG. 39 is an operation flowchart showing an example of the procedure of a transfer-to-other node processing in the home IPv4 mobile agent shown in FIG. 32 ;
FIG. 40 is an operation flowchart showing an example of the procedure of a transfer-to-home IPv4 mobile agent in the foreign IPv4 mobile agent shown in FIG. 32 ;
FIG. 41 is an operation flowchart showing an example of the procedure of a transfer-to-mobile node processing in the foreign IPv4 mobile agent shown in FIG. 32 ;
FIG. 42 is an explanatory view showing a structural example of an IPv4 movement registration request message;
FIG. 43 is an explanatory view showing a structural example of a packet obtained by IPv6 encapsulation of an IPv4 movement registration permission message;
FIG. 44 is an explanatory view showing a structural example of a packet obtained by IPv6 encapsulation of an IPv4 movement registration request message; and
FIG. 45 is an explanatory view showing a structural example of a packet obtained by IPv6 encapsulation of an IPv4 packet.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, preferred embodiments of the present invention will be explained with reference to the accompanying drawings.
FIG. 1 is a structural view showing a network system according to one embodiment of the present invention.
This network system 1 includes LAN (Local Area Network)-a 100 which makes use of both an IPv4 and an IPv6, a LAN-b 101 which makes use of only the IPv4 and a WAN (Wide Area Network) 102 which connects the LAN-a 100 and the LAN-b 101 by a public line or an exclusive line.
On the LAN-a 100 exist an IPv4 node 103 , an IPv6 node 104 , an IPv4 mobile agent-a 105 for assisting the movement of a node executing communication by utilizing the IPv4 by the procedure in accordance with a Mobile IPv4 between the networks, an IPv4/v6 mobile node 106 and an IPv6 mobile agent 107 for assisting the movement of the node which executes communication by utilizing the IPv4 and IPv6 and also executes communication by utilizing the IPv6 between the networks. The IPv6 mobile agent 107 functions also as a router and connects the LAN-a 100 and the WAN 102 .
An IPv4 mobile agent-b 108 and a router 109 exist on the LAN-b 101 . The router 109 connects the LAN-b 101 and the WAN 102 .
In this embodiment, the following IP addresses are allocated, respectively:
IPv4 address
IPv6 address
LAN-a 100
“10.0.0.0”
“::11.0.0.0”
IPv4 node 103
“10.0.0.10”
IPv6 node 104
“::11.0.0.30”
IPv4/v6 mobile node 106
“10.0.0.1”
“::11.0.0.1”
IPv4 mobile agent-a 105
“10.0.0.11”
IPv6 mobile agent 107
“10.0.0.20”
“::11.0.0.20”
LAN-b 101
“20.0.0.0”
IPv4 mobile agent-b 108
“20.0.0.11”
The IPv4/v6 mobile node 106 includes an IPv4/v6 movement processing portion 114 for executing various processings when the node moves to another network, a movement detection processing portion 115 for executing a detection processing which detects the movement to another network, an IPv4 movement registration processing portion 116 for executing a movement notification processing which notifies the movement of the node to another IPv4 network or to an IPv4/v6 network, to the IPv4 mobile agent-a 105 , an IPv6 movement registration processing portion 117 for executing a movement notification processing which notifies the movement of the node to another IPv6 network or to the IPv4/v6 network, to the IPv6 mobile agent 107 , an IPv4-only movement registration processing portion 118 for executing a movement notification processing which notifies the movement of the node to another IPv4 network to the IPv6 mobile agent 107 , a movement status management table 119 for managing the movement status, an IPv4 processing portion 111 for executing a processing in accordance with the services offered by the IPv4, an IPv6 processing portion 112 for executing a processing in accordance with the services offered by the IPv6, an IPv6 packet transmission processing portion 113 for executing a transmission processing of the IPv6 packet, and a communication processing portion 110 for executing a transmission/reception control of the packet to and from the LAN.
Among the constituent elements of the IPv4/v6 mobile node 106 described above, the present invention disposes specifically the movement detection processing portion 114 , the IPv4-only movement registration processing portion 118 , the IPv6 packet transmission processing portion 113 and the movement status management table 119 .
The IPv6 mobile agent 107 includes an IPv6 movement assistance processing portion 121 which receives the movement report (a report representing the movement to the IPv6 network or to the IPv4/v6 network) from the IPv6 mobile node (not shown in the drawing) effecting communication by utilizing the IPv4/v6 mobile node 106 or IPv6 and moving between the networks, and assists the mobile node, a mobile node management table 126 for managing the movement status information of the mobile nodes, an IPv4 processing portion 122 for executing a processing in accordance with the services offered by the IPv4, a transfer processing portion 123 to another node, for transferring the packet which is transmitted by the IPv4/v6 mobile node 106 to the IPv6 node 104 , an IPv6 processing portion 124 for executing a processing in accordance with the services offered from the IPv6, a transfer processing portion 125 to a mobile node, for transferring the packet which is transmitted from the IPv6 node 104 to the IPv4/v6 mobile node and a communication processing portion 120 for executing transmission/reception control of the packet to the LAN.
Among the constituent elements of the IPv6 mobile agent 107 described above, it is the IPv6 movement assistance processing portion 121 , the transfer processing portion 123 to another node, the transfer processing portion 125 to a mobile node, and a mobile node management table 126 that constitute the characterizing part of the present invention.
FIG. 2 shows a structural example of the movement status management table 119 .
This movement status management table 119 has the following fields:
Own IPv4 Address 200 :
This is the IPv4 address of the IPv4/v6 mobile node 106 on the LAN-a 100 on which the IPv6 mobile agent 107 for assisting the movement of the IPv4/v6 mobile node 106 exists.
Own IPv4 Network Address 201 :
This is the IPv4 network address of the LAN-a 100 on which the IPv6 mobile agent 107 for assisting the movement of the IPv4/v6 mobile node 106 exists.
Own IPv6 Address 202 :
This is the IPv6 address of the IPv4/v6 mobile node 106 on the LAN-a 100 on which the IPv6 mobile agent 107 for assisting the movement of the IPv4/v6 mobile node 106 exists.
Own IPv6 Network Address 203 :
This is the IPv6 network address of the LAN-a 100 on which the IPv6 mobile agent 107 for assisting the movement of the IPv4/v6 mobile node 106 exists.
IPv4 Mobile Agent IPv4 Address 204 :
This is the IPv4 address of the IPv4 mobile agent-a 105 on the LAN-a 100 on which the IPv4 mobile agent-a 105 for assisting the movement of the IPv4/v6 mobile node 106 exists.
IPv6 Mobile Agent IPv4 Address 205 :
This is the IPv4 address of the IPv6 mobile agent 107 on the LAN-a 100 on which the IPv6 mobile agent 107 for assisting the movement of the IPv4/v6 mobile node 106 exists.
IPv6 Mobile Agent IPv6 Address 206 :
This is the IPv6 address of the IPv6 mobile agent 107 on the LAN-a 100 on which the IPv6 mobile agent 107 for assisting the movement of the IPv4/v6 mobile node 106 exists.
Post-Movement IPv4 Network Address 207 :
This is the IPv4 network address of the network on which the IPv4/v6 mobile node 106 exists at the present moment.
Pre-Movement IPv4 Network Address 208 :
This is the IPv4 network address of the network before the IPv4/v6 mobile node 106 moves.
Post-Movement IPv6 Network Address 209 :
This is the IPv6 network address of the network in which the IPv4/v6 mobile node 106 exists at the present moment. When the network existing at present is the IPv4 network, “NULL” is set.
Pre-Movement IPv6 Network Address 210 :
This is the IPv6 network address of the network before the IPv4/v6 mobile node 106 moves. When the network before the movement is the IPv4 network, “NULL” is set.
Incidentally, the network address of the LAN-a 100 in which the IPv6 mobile agent 107 for assisting the movement of the IPv4/v6 mobile node 106 exists is set at the time of initialization to the field of each of the post-movement IPv4 network address 207 , the pre-movement IPv4 network address 208 , the post-movement IPv6 network address 209 and the pre-movement IPv6 network address 210 .
FIG. 3 shows a structural example of the mobile node management table 126 .
This mobile node management table 126 includes the following entries:
Mobile Node IPv6 Address 30 :
This is the IPv6 address of the mobile node the movement of which is assisted by the IPv6 mobile agent 107 .
Foreign IPv6 Address 31 :
This is the IPv6 address on the network on which the mobile node exists at the present moment. When the network existing at present is the IPv4 network, “NULL” is set.
Foreign IPv4 Address 32 :
This is the IPv4 address on the network on which the mobile node exists at the present moment. When the network existing at present is the IPv6 network, “NULL” is set.
Incidentally, the entry of the mobile node does not exist in the mobile node management table 126 at the time of initialization.
FIG. 4 is a flowchart showing the IPv4/v6 movement processing 40 executed by the IPv4/v6 movement processing portion 114 .
Initialization of the movement status management table 119 is effected at Step 41 .
At the next Step 50 , the movement detection processing portion 115 is caused to repeatedly execute a movement detection processing 50 .
FIG. 5 is a flowchart showing the movement detection processing 50 executed by the movement detection processing portion 115 .
At Step 51 , the IPv4/v6 mobile node 106 transmits a message transmission request message for detecting the IPv4 movement and a message transmission request message for detecting the IPv6 movement, which request an IPv4 movement detection message and an IPv6 movement detection message for detecting the movement to another IPv4 network, the IPv6 network or the IPv4/v6 network, respectively. The IPv4 mobile agent and the IPv6 mobile agent that receive these message transmission request message for detecting the IPv4 movement and message transmission request message for detecting the IPv6 movement, respectively, transmit the IPv4 movement detection message and the IPv6 movement detection message, respectively. In addition, the IPv4 mobile agent and the IPv6 mobile agent periodically transmit the IPv4 movement detection message and the IPv6 movement detection message, respectively.
Next, a timer is set at Step 52 .
If the IPv4 movement detection message is received at Step 53 , the flow proceeds to Step 54 and when it is not, the flow proceeds to Step 55 .
At Step 54 , the network address of the network, to which the IPv mobile agent transmitting the received IPv4 movement detection message belongs is compared with the post-movement IPv4 network address 207 inside the movement status management table 119 . If they are the same network address, the flow proceeds to Step 55 and if they are different network addresses, the flow proceeds to Step 60 .
If the IPv6 movement detection message is received at Step 55 , the flow proceeds to Step 56 and if it is not, the flow proceeds to Step 57 .
At Step 56 , the network address of the network to which the IPv6 mobile agent transmitting the IPv6 movement detection message received belongs is compared with the post-movement IPv6 network address 209 inside the movement status management table 119 . If they are the same network address, the flow proceeds to Step 57 and if they are different network addresses, the flow proceeds to Step 70 .
At Step 57 , the flow returns to Step 53 if the time is not out, and proceeds to Step 58 if the time is out.
At Step 58 , whether or not the post-movement IPv4 network address 207 inside the movement status management table 119 and the pre-movement IPv4 network address 208 are different addresses and whether or not the post-movement IPv6 network address 209 and the pre-movement IPv6 network address are the same network address are judged, and if the result of this judgement proves Yes, the flow proceeds to Step 80 and if the result proves No, the processing is completed.
At Step 60 , the IPv4 movement registration processing portion 116 is caused to execute the IPv4 movement registration processing 60 .
At Step 70 , the IPv6 movement registration processing portion 117 is caused to execute the IPv6 movement registration processing 70 .
At Step 80 , the IPv4-only movement registration processing portion 118 is caused to execute the IPv4-only movement registration processing 80 .
The movement detection processing 50 described above will be explained more concretely. When the IPv4/v6 mobile node 106 exists on the LAN-a 100 at the present moment, it receives the IPv4 movement detection message and the IPv6 movement detection message transmitted by the IPv4 mobile agent-a 105 and by the IPv6 mobile agent 107 , respectively. In this instance, since the network address (=“10.0.0.0”) of the LAN-a 100 to which the IPv4 mobile agent-a 105 transmitting the IPv4 movement detection message belongs is the same as the post-movement IPv4 network address 207 (=10.0.0.0”) of the movement status table 119 , it is possible to know that the mobile node does not move to another IPv4 network or another IPv4/v6 network. Therefore, the flow proceeds from Step 54 to Step 55 but Step 60 (IPv4 movement registration processing) is not executed. Since the network address (=“::11.0.0.0”) of the network to which the IPv6 mobile agent 107 transmitting the IPv6 movement detection message belongs is the same as the post-movement IPv6 network address 209 (=“::11.0.0.0”) of the movement status table 119 , it is possible to know that the mobile node does not move to another IPv6 or another IPv4/v6 network. Therefore, the flow proceeds from Step 56 to Step 57 but Step 70 (IPv6 movement registration processing) is not executed.
Next, when the IPv4/v6 mobile node 106 has moved to the LAN-b 101 at the present moment, this mobile node 106 receives the IPv4 movement detection message transmitted by the IPv4 mobile agent-b 108 . Since the network address (=“20.0.0.0”) of the LAN-b 101 to which the IPv4 mobile agent-b 108 transmitting the IPv4 movement detection message belongs is different from the post-movement IPv4 network address 207 (=“10.0.0.0”) of the movement status table 119 , it is possible to know that the IPv4/v6 mobile node 106 has moved to another IPv4 network or another IPv4/v6 network. Therefore, the flow proceeds from Step 54 to Step 60 , where the IPv4 movement registration processing 60 is executed. As will be described later with reference to FIG. 6 , the pre-movement IPv4 network address 208 of the movement status table 119 is updated to “10.0.0.0” and the post-movement IPv4 network address 207 is updated to “20.0.0.0”, by this IPv4 movement registration processing 60 .
On the other hand, because the IPv6 mobile agent does not exist in the LAN-b 101 , the IPv6 movement detection message is not received. In consequence, the flow proceeds from Step 55 to Step 57 and the processing of Steps 56 and 70 (IPv6 movement registration processing) is not executed.
Because the post-movement IPv4 network address 207 (=“20.0.0.0”) of the movement status table 119 is different from the pre-movement IPv4 network address 208 (=“10.0.0.0”) and because the post-movement IPv6 network address 209 (=“::11.0.0.0”) is the same as the pre-movement IPv6 network address 210 (=“::11.0.0.0”) after time-out, it is possible to know that the mobile node has moved to the IPv4 network. Therefore, the flow proceeds from Step 58 to Step 80 and the IPv4-only movement registration processing 80 is executed.
Incidentally, when the IPv4/v6 mobile node 106 moves to another IPv4/v6 network such as the LAN-a 100 , both of the IPv4 movement detection message and the IPv6 movement detection message are received. Therefore, both of the IPv4 movement registration processing 60 and the IPv6 movement registration processing 70 are executed. On the other hand, the post-movement IPv4 network address 207 of the movement status table 119 becomes inequal (≠) to the pre-movement IPv4 network address 208 and the post-movement IPv6 network address 209 becomes inequal (≠) to the pre-movement IPv6 network address 210 . Therefore, the flow does not proceed from Step 58 to Step 80 and the IPv4-only movement registration processing 80 is not executed.
FIG. 6 is a flowchart showing an example of the IPv4 movement registration processing executed by the IPv4 movement registration processing portion 116 . Incidentally, this IPv4 movement registration processing 60 is the processing which follows the processing procedure of the Mobile IPv4.
At Step 61 , the IPv4 network address 201 of the movement status management table 119 of its own is compared with the network address of the network to which the IPv4 mobile agent transmitting the IPv4 movement detection message belongs. When they are not the same network address, it is possible to know that the mobile node has moved to another network, and the flow proceeds to Step 62 . When they are the same network address, on the other hand, it is possible to know that the mobile node has returned to the LAN-a 100 in which the IPv6 mobile agent 107 assisting the movement of the IPv4/v6 mobile node 106 exists, and the flow then proceeds to Step 63 .
At Step 62 , the IPv4 address on the foreign network which the IPv4/v6 mobile node 106 can make use of is acquired. This IPv4 address can be acquired by utilizing a DHCP for executing automatic distribution of the addresses or by manual setting, for example.
At Step 63 , the IPv4 movement registration request message is transmitted to the IPv4 mobile agent registered to the IPv4 mobile node IPv4 address 204 of the movement status management table 119 .
At Step 64 , the movement registration permission message as the reply to the IPv4 movement registration request message is awaited from the IPv4 mobile agent, and after this IPv4 movement registration permission message is received, the flow proceeds to Step 65 .
At Step 65 , the post-movement IPv4 network address 207 of the movement status management table 119 is substituted for the pre-movement IPv4 network address 208 and then the network address of the network to which the IPv4 mobile agent transmitting the IPv4 movement detection message is substituted for the post-movement IPv4 network address 207 .
The IPv4 movement registration processing 60 described above will be explained more concretely. When the IPv4/v6 mobile node 106 moves from the LAN-a 100 to the LAN-b 101 , the flow proceeds from Step 61 to Step 62 and further to Step 63 , and transmits the IPv4 movement registration request message to the IPv4 mobile agent-a 105 . After the IPv4 movement registration permission is received from the IPv4 mobile agent-a 105 , the flow proceeds from Step 64 to Step 65 . Next, “10.0.0.0” is set to the pre-movement IPv4 network address 208 while “20.0.0.0” is set to the post-movement IPv4 network address 207 .
FIG. 7 is a flowchart showing an example of the IPv6 movement registration processing executed by the IPv6 movement registration processing portion 117 . Incidentally, this IPv6 movement registration processing 70 is the processing that follows the processing procedure of the Mobile IPv6.
At Step 71 , own IPv6 network address 203 of the movement status management table 119 is compared with the network address of the network to which the IPv6 mobile agent transmitting the IPv6 movement detection message belongs. When they are not the same network address, it is possible to know that the mobile node has moved to another network and the flow proceeds to Step 72 . When they are the same network address, on the other hand, it is possible to know that the mobile node has returned to the LAN-a 100 in which the IPv6 mobile agent 107 assisting the movement of the IPv4/v6 mobile node 106 exists, and the flow then proceeds to Step 73 .
At Step 72 , the IPv6 address on the foreign network which the IPv4/v6 mobile node 106 can make use of is acquired. Acquisition of this IPv6 address is made by utilizing the DHCP for executing automatic distribution of the addresses or by manual setting, for example.
At Step 73 , the IPv6 movement registration request message is transmitted to the IPv6 mobile agent registered to the IPv6 mobile agent IPv6 address 206 of the movement status management table 119 . This IPv6 movement registration request message contains its own IPv6 address 1301 , the foreign IPv6 address 1302 and the foreign IPv4 address 303 as shown in FIG. 13 . This IPv6 movement registration processing 70 sets the IPv6 address held by own IPv6 address 202 of the movement status management table 119 to its own IPv6 address 1301 , the foreign IPv6 address to the foreign IPv6 address 1302 and “NULL” to the foreign IPv4 address 1303 .
At Step 74 , the IPv6 movement registration permission message as the reply to the IPv6 movement registration request message is awaited from the IPv6 mobile agent, and after this permission message is received, the flow proceeds to Step 75 .
At Step 75 , the post-movement IPv6 network address 209 of the movement status management table 119 is substituted for the pre-movement IPv6 network address 210 and then the network address of the network to which the IPv6 mobile agent transmitting the IPv6 movement detection message belongs is substituted for the post-movement IPv6 network address 209 .
FIG. 8 is a flowchart showing an example of the IPv4-only movement registration processing executed by the IPv4-only movement registration processing portion 118 .
At Step 81 , the IPv4 encapsulated IPv6 movement registration request message is transmitted to the IPv6 mobile agent registered to the IPv6 mobile agent IPv6 address 206 of the movement status management table 119 . As shown in FIG. 14 , this IPv4 encapsulated IPv6 movement registration request message contains an IPv4 header 1401 and an IPv6 movement registration request message 1300 . The IPv4 header 1401 contains in turn a foreign IPv4 address 1402 and a source IPv4 address 1403 . The address of the IPv6 mobile agent IPv4 address 205 of the movement status management table 119 is set to the foreign IPv4 address 1402 and the IPv4 address acquired in the foreign IPv4 network is set to the source IPv4 address 1403 . The IPv6 movement registration request message 1300 shown in FIG. 14 contains its own IPv6 address 1301 , the foreign IPv6 address 1302 and the foreign IPv4 address 1303 as shown in FIG. 13 .
The IPv4-only movement registration processing 80 sets the IPv6 address held by the IPv6 address 202 of the movement status management table 119 to its own IPv6 address 1301 , “NULL” to the foreign IPv6 address 1302 and the IPv4 address at the destination to the foreign IPv4 address 1303 .
At Step 82 , the IPv4 encapsulated IPv6 movement registration permission request message as the reply to the IPv4 encapsulated IPv6 movement registration request message is awaited from the IPv6 mobile agent, and after this IPv4 encapsulated IPv6 movement registration permission message is received, and the flow proceeds to Step 83 . Incidentally, the IPv4 processing portion 111 removes the IPv4 header from the IPv4 encapsulated IPv6 movement registration permission message (this procedure will be hereinafter called the “IPv4 decapsulation”) and delivers it to the IPv4-only movement registration processing portion 118 . This IPv4 decapsulation in the IPv4 processing portion 111 is one of the services offered by the existing IPv4.
At Step 83 , the post-movement IPv6 network address 209 of the movement status management table 119 is substituted for the pre-movement IPv6 network address 210 and then “NULL” is substituted for the post-movement IPv6 network address 209 .
The IPv4-only movement registration processing 80 described above will be explained more concretely. When the IPv4/v6 mobile node 106 has moved from the LAN-a 100 to the LAN-b 101 , the following IPv4 encapsulated IPv6 movement registration request message 1400 is generated at Step 81 .
IPv4 Header:
foreign IPv4 address 1402 : “10.0.0.20”
(IPv4 address of IPv6 mobile agent 107 )
home IPv4 address 1403 : “20.0.0.1”
(IPv4 address that the IPv4/v6 mobile node 106 uses afresh on the LAN-b 101 ).
IPv6 Movement Registration Message 1300 :
own IPv6 address 1301 : “::11.0.0.1”
foreign IPv6 address 1302 : “NULL”
foreign IPv6 address 1303 : “20.0.0.1”.
The IPv4 encapsulated IPv6 movement registration permission message 1400 is transmitted to the IPv6 mobile agent 107 .
Next, after the IPv4 encapsulated IPv6 movement registration permission message is received from the IPv6 mobile agent 107 at Step 82 , “::11.0.0.1” is set to the pre-movement IPv6 network address 210 at Step 83 and “NULL” is set to the post-movement IPv6 network address 209 .
FIG. 9 is a flowchart showing an example of the IPv6 packet transmission processing 90 executed by the IPv6 packet transmission processing portion 113 of the IPv6 processing portion 112 in the IPv4/v6 mobile node 106 .
At Step 91 , the IPv6 packet transmission request by the network application, etc., is awaited, and the flow proceeds to Step 92 if the transmission request is made.
At Step 92 , whether or not the IPv6 network address 209 after the movement of the movement status management table 119 is “NULL” is checked and if it is “NULL”, the flow proceeds to Step 93 and if it is not, the flow proceeds to Step 94 .
At Step 93 , since the destination is the IPv4 network, the IPv6 packet is encapsulated by IPv4 encapsulation and is transmitted. In other words, the IPv4 header 1401 is added to the IPv6 packet 1501 as shown in FIG. 15 , the IPv6 mobile agent IPv4 address 205 of the movement status management table 119 is set to the foreign IPv4 address 1402 of that IPv4 header 1401 , the IPv4 address acquired by the foreign IPv4 network is set to the home IPv4 address, and the IPv4 encapsulated IPv6 packet 1500 is generated and transmitted. The flow then returns to Step 91 described above.
At Step 94 , since the destination is the IPv6 network or the IPv4/v6 network, the IPv6 is transmitted as such. The flow then returns to Step 91 described above.
The IPv6 packet transmission processing 90 will be explained more concretely. When the IPv4/v6 mobile node 106 moves from the LAN-a 100 to the LAN-b 101 , for example, the IPv4/v6 mobile node 106 receives the transmission request of the IPv6 packet 1501 by the network application at Step 91 . Then, “10.0.0.20” (IPv4 address of the IPv6 mobile agent 107 ) is set as the foreign IPv4 address to this IPv6 packet 1501 at Step 92 and furthermore, the IPv4 header 1401 to which “20.0.0.1” is set as the home IPv4 address 1403 is added. The IPv6 packet encapsulated by this IPv4 encapsulation is transmitted to the IPv6 mobile agent 107 .
FIG. 10 is a flowchart showing an example of the IPv6 movement assistance processing 1000 executed by the IPv6 movement assistance processing portion 121 of the IPv6 mobile agent 107 .
At Step 1001 , whether or not the message transmission request message for detecting the IPv6 movement is received from the IPv6 mobile node (not shown in the drawing) or the IPv4/v6 mobile node 106 is checked, and if it is, the flow proceeds to Step 1002 and if it is not, the flow proceeds to Step 1003 .
At Step 1002 , the IPv6 movement detection message is transmitted to the node which transmits the IPv6 movement detection message transmission request message described above.
At Step 1003 , whether or not the IPv6 movement registration request message 1300 is received is checked, and if it is, the flow proceeds to Step 1004 and if it is not, the flow returns to Step 1001 .
At Step 1004 , whether or not the movement registration request can be accepted is checked, and if it cannot be accepted, the flow proceeds to Step 1005 and if it can, the flow proceeds to Step 1006 .
At Step 1005 , the IPv6 movement registration rejection message is transmitted to the node that transmits the IPv6 movement registration request message 1300 . The flow then returns to Step 1001 described above.
At Step 1006 , own IPv6 address 1301 of the IPv6 movement registration request message 1300 is compared with the foreign IPv6 address 1302 and when they are the same address, the flow proceeds to Step 1007 and when they are different addresses, the flow proceeds to Step 1008 .
At Step 1007 , the information of the corresponding mobile node inside the mobile node management table 126 is deleted by judging that this mobile node returns to its own network. The flow then proceeds to Step 1011 .
At Step 1008 , the foreign IPv4 address 1303 inside the IPv6 movement registration request message 1300 is checked, and if “NULL” is set, the flow proceeds to Step 1009 and if it is not, the flow proceeds to Step 1010 .
At Step 1009 , the information of the mobile node is set to the mobile node management table 126 by judging that this mobile node moves to the IPv6 network or to the IPv4/v6 network. In other words, the value of the foreign IPv6 address 1302 inside the IPv6 movement registration request message 1300 so received is set to the foreign IPv6 address 31 inside the mobile node management table 126 and “NULL” is set to the foreign IPv4 address 32 . The flow then proceeds to Step 1011 .
At Step 1010 , the information of the corresponding mobile node is set to the mobile node management table 126 by judging that this mobile node has moved to the IPv4 network. In other words, “NULL” is set to the foreign IPv6 address 31 inside the mobile node management table 126 while the value of the foreign IPv4 address 1303 inside the IPv6 movement registration request message 1300 so received is set to the foreign IPv4 address 32 . The flow then proceeds to Step 1012 .
At Step 1011 , the IPv6 movement registration permission message is transmitted to the mobile node, and the flow returns to Step 1001 described above.
At Step 1012 , the IPv6 movement registration permission message encapsulated by IPv4 encapsulation is transmitted to the mobile node. In other words, as shown in FIG. 16 , the IPv4 header 1401 is added to the IPv6 movement registration permission message 1601 , and the foreign IPv4 address 1303 inside the IPv6 movement registration request message 1300 is set to the foreign IPv4 address 1402 of the IPv4 header 1401 . Further, the IPv4 address of the IPv6 mobile agent 107 is set to the home IPv4 address 1403 and the IPv4 encapsulated IPv6 movement registration permission message is generated and transmitted. The flow then returns to Step 1001 .
Incidentally, when the IPv4/v6 mobile node 106 moves to the IPv4 network, the IPv4/v6 mobile node 106 transmits the IPv4 encapsulated IPv6 movement registration request message 1300 to the IPv6 mobile agent 107 as described already. When the IPv6 mobile agent 107 receives this IPv4 encapsulated IPv6 movement registration request message 1300 , IPv4 decapsulation of this message is executed at the IPv4 processing portion 122 and the IPv6 movement registration request message 1300 is taken out and delivered to the IPv6 movement assistance processing portion 121 . Since this processing is one of the services offered by the existing IPv4, any new function need not be added to the IPv4 processing portion 122 .
The IPv6 movement assistance processing 1000 described above will be explained more concretely. When the IPv4/v6 mobile node 106 has moved from the LAN-a 100 to the LAN-b 101 , the flow proceeds serially to Steps 1001 , 1002 , 1003 and 1004 , and since the foreign IPv6 address 1302 (=“NULL”) inside the IPv6 movement registration request message 1300 is different from own IPv6 address 1301 (=“::11.0.0.1”) at Step 1005 , the flow proceeds to Step 1008 .
At Step 1006 , since the foreign IPv4 address 1303 (=“20.0.0.1”) inside the IPv6 movement registration request message 1300 is not “NULL”, the flow proceeds to Step 1010 . At this Step 1010 , “::11.0.0.1” is registered to the mobile node IPv6 address 30 in the mobile node management table 126 as the information of the IPv4/v6 mobile node 106 , “20.0.0.1” is registered to the foreign IPv4 address 32 , and “NULL” is registered to the foreign IPv6 address 31 . At Step 1012 , the IPv4 header 1401 to which “20.0.0.1” is set as the foreign IPv4 address 1402 and “10.0.0.20” is set as the home IPv4 address 1403 is added to the IPv6 movement registration permission message 1601 and is transmitted to the IPv4/v6 mobile node 106 .
FIG. 11 is a flowchart showing an example of the transfer-to-mobile node processing 1100 which is executed by the transfer-to-mobile node processing portion 125 of the IPv6 processing portion 124 in the IPv6 mobile agent 107 .
At Step 1101 , reception of the IPv6 packet to the mobile node registered to the mobile node management table 126 among the IPv6 packets transmitted by the IPv6 node 104 and other IPv6 nodes (not shown in the drawing) is awaited, and after this packet is received, the flow proceeds to Step 1102 .
At Step 1102 , whether or not the foreign IPv6 address 31 of the corresponding mobile node inside the mobile node management table 126 is “NULL” is checked, and if it is “NULL”, the flow proceeds to Step 1103 and if it is not, the flow proceeds to Step 1104 .
At Step 1103 , the mobile node as the destination of the IPv6 packet is judged as moving to the IPv4 network, and the IPv6 packet is encapsulated by IPv4 encapsulation and is transmitted to the IPv4 network to which the mobile node as the destination of this packet is moving. The structure of the IPv4 encapsulated IPv6 packet at this time is shown in FIG. 15 . The foreign IPv4 address 32 of the corresponding mobile node inside the mobile node management table 126 is set to the foreign IPv4 address 1402 and the IPv4 address of the IPv6 mobile agent 107 is set to the home IPv4 address 1403 . The flow then returns to Step 1101 .
At Step 1104 , the mobile node as the destination of the IPv6 packet is judged as moving to the IPv6 network or to the IPv4/v6 network, and the IPv6 header is added afresh to the IPv6 packet (this processing will be hereinafter called “IPv6 encapsulation”) and is transmitted to the IPv6 network or to the IPv4/v6 network to which the mobile node is moving. In other words, as shown in FIG. 17 , the IPv6 header 1701 is added to the IPv6 packet 1704 , the foreign IPv6 address 31 of the corresponding mobile node inside the mobile node management table 126 is set to the foreign IPv6 address 1702 of its IPv6 header 1701 , the IPv6 address of the IPv6 mobile agent 107 is set to the home IPv6 address 1703 and the IPv6 encapsulated IPv6 packet 1700 is generated and transmitted. The flow then returns to Step 1101 . Incidentally, the processing procedure for encapsulating the IPv6 packet by the IPv6 encapsulation is the procedure that follows the Mobile IPv6.
The transfer-to-mobile node processing 1100 described above will be explained more concretely. When the IPv4/v6 mobile node 106 has moved from the LAN-a 100 to the LAN-b 101 , “::11.0.0.1” is set as the information of the IPv4/v6 mobile node 106 to the mobile node IPv6 address 30 inside the mobile node management table 126 by the IPv6 movement assistance processing 1000 described already, “NULL” is set to the foreign IPv6 address 31 and 20.0.0.11 is set to the foreign IPv4 address 32 . Therefore, when the IPv6 mobile agent 107 receives the IPv6 packet addressed to the IPv4/v6 mobile node 106 , it adds the header IPv4 header 1401 , in which “20.0.0.1” is set to the foreign IPv4 address 1402 and “10.0.0.20” is set to the home IPv4 address 1403 , to this IPv6 packet and transfers it to the IPv4/v6 mobile node 106 of the LAN-b 101 . This IPv4 encapsulated IPv6 packet 1500 is received by the IPv4/v6 mobile node 106 , is IPv4-decapsulated by the IPv4 processing portion 111 and is processed as the ordinary IPv6 packet.
In this way, even when the IPv4/v6 mobile node moves from the LAN-a 100 as the IPv4/v6 network to the LAN-b 101 as the IPv4 network, this mobile node can receive the IPv6 packet transmitted by the IPv6 node 104 of the LAN-a 100 .
FIG. 12 is a flowchart showing an example of the transfer-to-other node processing 1200 executed by the transfer-to-other node processing portion 123 of the IPv4 processing portion 122 in the IPv6 mobile agent 107 .
At Step 1201 , the mobile agent awaits the reception of the IPv4 packet addressed to its own (IPv6 mobile agent 107 ) and when this packet is received, the flow proceeds to Step 1202 .
At Step 1202 , whether or not the IPv4 packet so received is the IPv6 packet encapsulated by IPv4 encapsulation is checked, and when it is the IPv4 encapsulated IPv6 packet, the flow proceeds to Step 1203 and when it is not, the flow proceeds to Step 1205 .
At Step 1203 , whether or not the home node of the IPv4 encapsulated IPv6 packet is the mobile node registered to the mobile node management table 126 is checked, and if it is registered, the flow proceeds to Step 1204 and if it is not, the flow proceeds to Step 1205 .
At Step 1204 , the IPv4 encapsulated IPv6 packet is decapsulated by IPv4 decapsulation and is transmitted to the network where the node as the destination exists. The flow then returns to Step 1201 .
At Step 1205 , the IPv4 packet so received is discarded. The flow then returns to Step 1201 .
The transfer-to-other node processing 1200 described above will be explained more concretely. Let's consider the case where the IPv4/v6 mobile node 106 transmits the IPv6 packet to the IPv6 node 104 . In this instance, the IPv6 packet is subjected to IPv4 encapsulation by the IPv6 packet transmission processing 90 by using the IPv4 header 1401 in which “10.0.0.20” is set as the foreign IPv4 address 1402 (addressed to the IPv6 mobile agent 107 ) and “20.0.0.1” is set as the home IPv4 address 1403 , and the IPv4 encapsulated IPv6 packet is transmitted to the IPv6 mobile agent 107 . Receiving this packet, the IPv6 mobile agent 107 removes the IPv4 header 1401 of the IPv4 encapsulated IPv6 packet at Step 1204 after passing through Steps 1201 , 1202 and 1203 , and transmits the IPv6 packet 1501 to the LAN-a 100 in which the IPv6 node 104 as the address exists. This IPv6 packet is received as the ordinary IPv6 packet by the IPv6 node 104 .
As described above, even when the mobile node has moved from the LAN-a 100 as the IPv4/v6 network to the LAN-b 101 as the IPv4 network, the IPv4/v6 mobile node 106 can transmit the IPv6 packet to the IPv6 node 104 of the LAN-a 100 .
Incidentally, communication utilizing the IPv4 between the IPv4/v6 mobile node 106 and other nodes can be carried out by the movement assistance of the nodes in the IPv6 by the IPv4 mobile agent-1 105 and the IPv4 mobile agent-b 108 supporting the Mobile IPv4 as the existing method.
When the IPv4/v6 mobile node 106 returns from the LAN-b 101 to the LAN-a 100 , the IPv4/v6 mobile node 106 detects the movement to the IPv6 or to the IPv4/v6 network by the movement detection processing described above. The mobile node is judged as returning to the LAN-a 100 by the IPv6 movement registration processing 70 , and transmits the IPv6 movement registration request message 1300 in which “::11.0.0.1” is set to its own IPv6 address, “::11.0.0.1” which is the same as its own IPv6 address 1301 to the foreign IPv6 address 1302 and “NULL” to the foreign IPv4 address 1303 , to the IPv6 mobile agent 107 .
Receiving the IPv6 movement registration request message 1300 , the IPv6 mobile agent 107 judges that the IPv4/v6 mobile node 106 returns to the LAN-a 100 because its own IPv6 address inside the IPv6 movement registration request message 1300 is the same as the foreign IPv6 address 1302 , and omits the information on the IPv4/v6 mobile node 106 inside the mobile node management table 126 . As a result, the IPv4/v6 mobile node 106 can make communication utilizing the ordinary IPv6.
Incidentally, the IPv4/v6 mobile node 106 reports its return to the LAN-a 100 to the IPv4 mobile agent-a 105 , too, by the IPv4 movement registration request message in accordance with the Mobile IPv4 processing procedure and for this reason, communication utilizing the ordinary IPv4 can be made, too.
The embodiment given above automatically detects the movement between the networks by utilizing the IPv4 movement detection message and the IPv6 movement detection message, but it is also possible to employ the construction in which the user of the mobile node reports by himself to the movement detection processing portion 116 so as to execute the IPv4 movement registration processing 60 , the IPv6 movement registration processing 70 or the IPv4-only movement registration processing 80 .
Next, another embodiment of the present invention will be explained with reference to the drawings.
First, the explanation will be given on the case where the IPv4/v6 mobile node moves from the IPv4/v6 network to the IPv4 network.
A structural example of the network system to which the present invention is applied and a structural example of the mobile agent will be explained with reference to FIG. 18 . As shown in the drawing, the network system according to this embodiment includes a LAN-a 1800 , a LAN-b 1801 and a WAN 1802 that connects the LAN-a 1800 and the LAN-b 1801 by a public line or an exclusive line. On the LAN-a 1800 exist an IPv4 node 1803 which executes communication by utilizing only the IPv4 as a protocol of a network layer as the third layer of an OSI reference model, an IPv6 node 1804 which executes communication by utilizing only the IPv6, an IPv4 mobile agent-a 1805 which assists the movement between the networks for the nodes executing communication by utilizing the IPv4 in accordance with the procedure of the Mobile IPv4, an IPv4/v6 mobile node 1806 which executes communication by utilizing both IPv4 and IPv6 and moves between the networks, and a home IPv6 mobile agent 1807 which assists the movement of a node when the node executing communication by utilizing the IPv6 modes to another network.
On the LAN-b 1801 exist an IPv4 mobile agent-b 1808 and a foreign IPv6 mobile agent 1809 which assists the movement of a node when the node executing communication by utilizing the IPv4 and the IPv6 and executing communication by utilizing IPv6 comes to the LAN-b 1801 .
Incidentally, the home IPv6 mobile agent 1807 functions also as a router handling both of the IPv4 packet and the IPv6 packet and connects the LAN-a 1800 and the WAN 1802 . The router 1810 handling only the IPv4 packet connects the LAN-b 1801 and the WAN 1802 . Therefore, whereas both of the IPv4 packet and the IPv6 packet can come out from the networks beyond the router from the LAN-a 1800 , only the IPv4 packet can come out from the LAN-b 1801 . Incidentally, transmission/reception itself of the IPv4 packet and the IPv6 packet can be made inside the LAN-a 1800 and the LAN-b 1801 .
In this embodiment, the IP addresses are listed below:
IPv4 address
IPv6 address
IPv4 node 1803
“10.0.0.10”
IPv6 node 1804
“11::20”
IPv4/v6 mobile node 1806
“10.0.0.30”
“11::30”
IPv4 mobile agent-a 1805
“10.0.0.11”
home IPv6 mobile agent 1807
“10.0.0.1”
“11::1”
IPv4 mobile agent-b 1808
“20.0.0.11”
foreign IPv6 mobile agent 1809
“20.0.0.1”
“21::1”
The IPv4/v6 mobile node 1806 comprises an IPv4 movement processing portion 1813 which executes a processing in accordance with the Mobile IPv4 when the node moves to another IPv4 network or to an IPv4/v6 network, an IPv6 movement processing portion 1815 which executes a processing in accordance with the Mobile IPv6 when the mobile node moves to another IPv6 network or to an IPv4/v6 network, an IPv4 processing portion 1812 which executes a processing in accordance with the services offered by the IPv4, an IPv6 processing portion 1814 which executes a processing in accordance with the services offered by the IPv6 and a communication processing portion 1811 which executes a transmission/reception control, etc. of a packet to the LAN.
The home IPv6 mobile agent 1807 comprises an IPv6 movement assistance portion 1817 which assists the movement for the mobile node (not particularly shown in the drawing) executing communication by utilizing the IPv6 and moving between the networks or for an IPv6 mobile node 1806 , a mobile node management table 1822 which manages the information of the mobile node that has moved to another IPv6 network or to the IPv4/v6 network, an IPv6 processing portion 1818 which executes a processing in accordance with the services offered by the IPv4, a transfer-to-other node processing portion 1819 which executes a transfer processing of the IPv6 packet, which is transferred from the foreign IPv6 mobile agent 1809 and is transmitted by the IPv4/v6 mobile node 1806 , to the IPv6 node as the destination, an IPv6 processing portion 1820 which executes a processing in accordance with the services offered by the IPv6, a transfer-to-foreign IPv6 mobile agent processing portion 1821 which executes a transfer processing of the IPv6 packet, which is transmitted from another IPv6 node to the IPv4/v6 mobile node 1806 , to the foreign IPv6 mobile agent 1809 and a communication processing portion 1816 which executes a transmission/reception control, etc. of the packet to the LAN.
The foreign IPv6 mobile agent 1809 comprises a foreign IPv6 movement assistance portion 1823 which assists the movement of the IPv4/v6 mobile node 1806 when this node 1806 moves to the network (LAN-b 1801 ) to which the foreign IPv6 mobile agent 1809 belongs, a movement assistance management table 1828 which manages the information of this mobile node 1806 , a mobile agent address table 1830 which registers the address information of the home IPv6 mobile agent 1807 , an IPv4 processing portion 1824 which executes a processing in accordance with the services offered by the IPv4, a transfer-to-mobile node processing portion 1825 which executes a processing for transferring the packet, which is transferred from the home IPv6 mobile agent 1807 and is addressed to the IPv4/v6 mobile node 1806 , to the IPv4/v6 mobile node 1806 , an IPv6 processing portion 1826 which executes a processing in accordance with the services offered by the IPv6, a transfer-to-home IPv6 mobile agent processing portion 1812 which executes a processing for transferring the IPv6 packet, which is transmitted by the IPv4/v6 mobile node 1810 to another IPv6 node, to the home IPv6 mobile agent 1807 , and a communication processing portion 1829 which executes a transmission/reception control, etc. of the packet to the LAN.
Among the constituent elements of the home IPv6 mobile agent 1807 described above, it is the IPv6 movement assistance portion 1817 , the transfer-to-other node processing portion 1819 , the transfer-to-foreign IPv6 mobile agent processing portion 1821 and the mobile node management table 1822 that constitute the characterizing part of the present invention. Among the constituent elements of the foreign IPv6 mobile agent 1809 , it is the foreign IPv6 movement assistance portion 1823 , the transfer-to-mobile node processing portion 1825 , the transfer-to-home IPv6 mobile agent processing portion 1827 , the mobile agent address table 1830 and the mobile agent management table 1828 that constitute the characterizing part of the present invention.
FIG. 19 shows an example of the mobile node management table 1822 . As shown in this drawing, the mobile node management table- 1822 includes a mobile node IPv6 address 1920 as the IPv6 address of the mobile node, the foreign IPv6 address 1921 representing the IPv6 address which the mobile node makes use of in the foreign IPv6 network or in the foreign IPv4/v6 network, and a foreign IPv6 mobile agent IPv4 address 1922 representing the IPv4 address of the foreign IPv6 mobile agent 109 . Here, when the mobile node moves to the IPv6 network or to the IPv4/v6 network, “NULL” is set to the foreign IPv6 mobile agent IPv4 address 1922 and when the mobile node moves to the IPv4 network, the IPv4 address of the foreign IPv6 mobile agent 1809 existing inside that network is set to the address 1922 . Incidentally, though the drawing shows the case where the entries for a plurality of mobile nodes exist, the entry of the mobile node does not exist in this table under the initial state. Further, the updating processing of this table will be described later.
FIG. 20 shows an example of the mobile agent address table 1830 described above. As shown in this drawing, the mobile agent address table 1830 includes the home IPv6 mobile agent IPv4 address 2030 and the home IPv6 mobile agent IPv6 address 2031 as the IPv4 address and the IPv6 address of all the home IPv6 mobile agents existing in the network system (though this embodiment represents only the home IPv6 mobile agent 1807 on LAN-a 1800 ). This table is set by a manager, for example.
FIG. 21 shows an example of the movement assistance management table 1828 described above. As shown in the drawing, the movement assistance management table 1828 includes a mobile node IPv6 address 2140 as the IPv6 address of the IPv4/v6 mobile node 1806 , a home IPv6 mobile agent IPv4 address 2141 as the IPv4 address of the home IPv6 mobile agent 1807 existing in the home network of the mobile node, and a registration flag 2142 representing whether the entry is “tentative registration” or “real registration”. Incidentally, though this drawing represents the case where the entries for a plurality of mobile nodes exist, the entry of the mobile node does not exist in this table under the initial state. The updating processing of this table will be described later.
In the construction described above, the processings of the IPv4/v6 mobile node 1806 , the home IPv6 mobile agent 1807 and the foreign IPv6 mobile agent 1809 when the IPv4/v6 mobile node 1806 moves from the LAN-a 1800 as the IPv4/v6 network to the LAN-b 1801 as the IPv4 network, and handling of each table described above, will be explained next in detail.
FIG. 22 is a flowchart showing an example of the processing of the IPv4 movement processing portion 1812 for detecting whether or not the IPv4/v6 mobile node 1806 has moved to another IPv4 network or to the IPv4/v6 network, and for executing various processings when the mobile node has moved. By the way, this IPv4 movement processing portion 1812 executes the processing in accordance with the processing procedure of the Mobile IPv4.
The IPv4 movement processing portion 1812 first transmits the message transmission request message for detecting the IPv4 movement as the message for requesting the transmission of the IPv4 movement detection message, which is in turn the message for detecting the movement of the mobile node to another IPv4 network or to the IPv4/v6 network (Step 2251 ). Incidentally, the IPv4 movement detection message is transmitted by the IPv4 mobile agent either periodically or when it receives the transmission request message of the IPv4 movement detection. Next, the IPv4 movement processing portion 1812 judges whether or not the IPv4 movement detection message is received (Step 2252 ). When the IPv4 movement detection message is received (Step 2252 YES), the IPv4 movement processing portion 1812 judges from this message whether or not the mobile node moves to another network (Step 2253 ). Incidentally, the network address information is set inside the IPv4 movement detection message, and the movement is detected by comparing this address information with the IPv4 address of the IPv4/v6 mobile node 1806 of its own.
When the movement of the mobile node to another network is found as a result of the judgement described above (Step 2253 YES), the IPv4 movement processing portion 1812 judges next whether or not the network as the visiting network is the home network of the IPv4/v6 mobile node 1806 (the LAN-a 1800 is the home network in this embodiment) (Step 2254 ). The IPv4 movement detection message is utilized at the time of this judgement, too. When it is not the home network as a result of this judgement, (Step 2254 NO), the IPv4 movement processing portion 1812 then acquires the foreign IPv4 address that is used by the IPv4 mobile node-a 1805 when it transfers the IPv4 packet bound to the IPv4/v6 mobile node 1806 to the mobile node that is moving to another network (Step 2255 ). The IPv4/v6 mobile node 1806 acquires this foreign IPv4 address from the addresses offered by the IPv4 mobile agent-b 1808 or by utilizing the DHCP that automatically distributes the addresses, or by manual setting.
To report and register the movement to the IPv4 mobile agent-a 1805 , the IPv4 movement processing portion 1812 transmits the IPv4 movement registration message (Step 2256 ). Thereafter, the IPv4 movement processing portion 1812 waits for the IPv4 movement registration permission message as the reply of the IPv4 movement registration request message from the IPv4 mobile agent-a 1805 (Step 2257 ) and after this message is received (Step 2257 YES), the flow returns again to the first step 2251 . The IPv4 movement processing portion 1812 repeats the processing described above.
FIG. 23 is a flowchart showing an example of the processing of the IPv6 movement processing portion 1815 for detecting whether or not the IPv4/v6 mobile terminal 1806 has moved to another IPv6 network or to the IPv4/v6 network and for executing various processings when this mobile node has moved. Incidentally, this IPv6 movement processing portion 1815 executes the processing in accordance with the procedure of the Mobile IPv6.
The IPv6 movement processing portion 1815 first transmits the message transmission request message for detecting the IPv6 movement, which is the message for requesting the transmission of the IPv6 movement detection message as the message for detecting the movement to another IPv6 network or to the IPv4/v6 network (Step 2361 ). Incidentally, this IPv6 movement detection message is transmitted by the IPv6 mobile agent either periodically or when it receives the message transmission request message for detecting the IPv6 movement. Next, the IPv6 movement processing portion 1815 judges whether or not the IPv6 movement detection message is received (Step 2362 ). When this IPv6 movement detection message is received (Step 2362 YES), the IPv6 movement processing portion 1815 judges from this message whether or not the mobile node has moved to another network (Step 2362 ). Incidentally, the network address information is set into the IPv6 movement detection message, and the movement detection is executed by comparing this address information with its own IPv6 address of the IPv4/v6 mobile terminal 1806 .
If the result of judgement represents that the mobile node has moved to another network (Step 2363 YES), the IPv6 movement processing portion 1815 judges next whether or not the visiting network is the home network (the LAN-a 1800 is the home network in this embodiment) (Step 2364 ). The IPv6 movement detection message is utilized for this judgement, too. When the destination of the movement is not the home network as a result of the judgement described above (Step 2364 NO), the IPv6 movement processing portion 1815 then acquires the IPv6 address that can be used in the visiting network. Acquisition of this IPv6 address is made by utilizing the DHCP which automatically distributes the address, by the address automatic generation function as one of the functions offered by the IPv6, or by manual setting. In order to report and register the movement to the home IPv6 mobile agent 1807 , the IPv6 movement processing portion 1815 transmits the IPv6 movement registration request message (Step 2366 ).
FIG. 30 shows the data structure of the IPv6 movement registration request message transmitted by the IPv4/v6 mobile node 1806 . As shown in the drawing, the IPv6 movement registration request message 3000 includes a IPv6 header 3001 and a IPv6 data 3004 . The IPv6 header 3001 includes a foreign IPv6 address 3002 and a home IPv6 address. The IPv6 address of the home IPv6 mobile agent 1807 is set to the home IPv6 address 3002 , and the IPv6 address which the IPv4/v6 mobile node 1806 acquires in the visiting network is set to the home IPv6 address 3003 . The IPv6 data 3004 includes the IPv6 address 3005 as the IPv6 address of the node itself transmitting this message and the foreign IPv6 address 3006 as the IPv6 address which the mobile node acquires afresh in the visiting network. When the IPv4/v6 mobile node 1806 returns to the LAN-a 1800 as the home network, the same address as its own IPv6 address 3005 is set to the foreign IPv6 address 3006 .
Thereafter, the IPv6 movement processing portion 1815 awaits until the IPv6 movement registration permission message as the reply of the IPv6 movement registration request message 3000 is received from the home IPv6 mobile agent 1807 (Step 2367 ) and after this message is received (Step 2367 YES), the flow returns again to the initial Step 2361 . Thereafter, the IPv6 movement processing portion 1815 repeats the processing described above.
FIG. 24 is a flowchart showing an example of the processing of the IPv6 movement assistance processing portion 1817 which executes the assistance processing for the movement of the IPv6 mobile node (not particularly shown in the drawing) or the IPv4/v6 mobile node 1806 between the networks.
The IPv6 movement assistance processing portion 1817 first judges whether or not the IPv6 movement detection message transmission message is received (Step 2401 ). When this message is found received as a result of this judgement (Step 2401 YES), the IPv6 movement assistance processing portion 1817 transmits the IPv6 movement detection message (Step 2402 ). The IPv6 movement assistance processing portion 1817 then judges whether or not the IPv6 movement registration request message 3000 is received (Step 2403 ). If the message is found received as a result of judgement (Step 2403 YES), the IPv6 movement assistance processing portion further judges whether or not the request for this movement registration is acceptable (Step 2404 ). If the request is found unacceptable as a result of judgement (Step 2404 NO), the IPv6 movement assistance processing portion 1817 transmits the IPv6 movement registration rejection message as the registration rejection reply message of the IPv6 movement registration request message 3000 to the mobile node.
If the request is acceptable (Step 2404 YES), the IPv6 movement assistance processing portion 1817 then compares its own IPv6 address 3005 inside the message with the foreign IPv6 address (Step 2406 ). If they are found the same as a result of this comparison (Step 2406 YES), the IPv6 movement assistance processing portion 1817 judges that the mobile node has returned to the home network, and deletes the corresponding information of the mobile node inside the mobile node management table 1812 (Step 2407 ). Then, the IPv6 movement assistance processing portion 1817 transmits the IPv6 movement registration permission message as the registration permission reply message of the IPv6 movement registration request message 3000 to the mobile node (Step 2411 ).
When the IPv6 address 3005 and the foreign IPv6 address 3006 are found as the different addresses as a result of comparison (Step 2406 NO), the IPv6 movement assistance processing portion 1817 further judges whether or not the IPv6 movement registration request message 300 so received is encapsulated by IPv4 encapsulation and transferred from the foreign IPv6 mobile agent 1809 (Step 2008 ). Incidentally, IPv4 encapsulation of the IPv6 movement registration request message 3000 by the foreign IPv6 mobile agent 1809 is effected by the later-appearing foreign IPv6 movement assistance processing portion 1823 inside the foreign IPv6 mobile agent 1809 . When the home IPv6 mobile agent 1807 receives this IPv4 encapsulated IPv6 movement registration request message 3000 , its own IPv4 processing portion 1818 executes IPv4 decapsulation and delivers the decapsulated message to the IPv6 movement assistance processing portion 1817 . This IPv4 decapsulation by the IPv4 processing portion 1818 is one of the services offered by the existing IPv4.
When the message is not judged as being transferred as a result of the judgement as to IPv4 decapsulation and transfer (Step 2408 NO), the IPv6 movement assistance processing portion 1817 judges that the mobile node has moved to another IPv6 network or to the IPv4/v6 network and sets the information of this mobile node to the mobile node management table 1822 . At this time, the value of the foreign IPv6 address 3006 inside the IPv6 movement registration request message 3000 , which is received, is set to the foreign IPv6 address 1921 inside the mobile node management table 1822 and “NULL” is set to the foreign IPv6 mobile agent IPv4 address 1922 (Step 2409 ). The IPv6 movement assistance processing portion 1817 then transmits the IPv6 movement registration permission message to the mobile node (Step 2411 ).
When the message is found as being IPv4 encapsulated and transferred as a result of the judgement described above (Step 2408 YES), the IPv6 movement assistance processing portion 1817 judges that the mobile node has moved to the IPv4 network and sets the information of this mobile node to the mobile node management table 1822 . At this time, the value of the foreign IPv6 address 3005 inside the IPv6 movement registration request message 3000 , which is transferred, is set to the foreign IPv6 address 1921 inside the mobile node management table 1822 , and the value of the home IPv4 address inside the IPv4 header, which is added to the IPv6 movement registration request message 3000 transferred, is set to the foreign IPv6 mobile agent IPv6 address 1922 . The IPv6 movement assistance processing portion 1817 then executes IPv4 encapsulation of the IPv6 movement registration permission message as the reply to the mobile node and transfers the message (Step 2412 ).
The structure of the IPv6 movement registration permission message which is IPv4 encapsulated at this time is the same as the structure 1600 shown in FIG. 16 . The foreign IPv6 mobile agent IPv4 address 1922 registered to the mobile node-management table 1822 is set to the foreign IPv4 address 1402 inside the IPv4 header 1401 , and own IPv4 address of the home IPv6 mobile agent 1807 is set to the home IPv4 address 1403 .
The IPv6 movement assistance processing portion 1817 completes the processings as described above and repeats thereafter the processing described above.
FIG. 25 is a flowchart showing an example of the processing of the foreign IPv6 movement assistance processing portion 1823 which executes the movement assistance processing for the IPv4/v6 mobile node 1806 between the networks at the foreign IPv6 mobile agent 1809 .
The foreign IPv6 movement assistance processing portion 1823 first judges whether or not the message transmission request message for detecting the IPv6 movement is received (Step 2501 ). When this message is found received as a result of the judgement (Step 2501 YES), the foreign IPv6 movement assistance processing portion 1823 transmits the IPv6 movement detection message (Step 2502 ). Next, the foreign IPv6 movement assistance processing portion 1823 judges whether or not the IPv6 movement registration request message 3000 is received (Step 2503 ). If this message is found received as a result of the judgement (Step 2503 YES), the IPv6 movement assistance processing portion 1823 registers tentatively the information of this mobile node to the movement assistance management table 1828 (Step 1804 ). At this time, the value of own IPv6 address 3005 inside the IPv6 movement registration request message 3000 received is set to the mobile node IPv6 address 2140 of the movement assistance management table 1828 , and the value of the home IPv6 mobile agent IPv4 address 2030 corresponding to the foreign IPv6 address 3002 inside the IPv6 movement registration request message 3000 is set to the home IPv6 mobile agent IPv4 address 2141 by looking up the mobile agent address table 1830 . Further, “tentative registration” is set to the registration flag. The foreign IPv6 movement assistance processing portion 1823 executes IPv4 encapsulation of the IPv6 registration request message 3000 so received and transfers the encapsulated message to the home IPv6 mobile agent 1807 (Step 2505 ).
The structure of the IPv4 encapsulated IPv6 movement registration request message at this time is the same as the structure 1400 shown in FIG. 14 . The IPv4 address 2141 of the home IPv6 mobile agent 1807 registered to the movement assistance management table 1828 is set to the foreign IPv4 address 1402 in the IPv4 header 1401 , and own IPv4 address of the foreign IPv6 mobile agent 1809 is set to the home IPv4 address 1403 .
Incidentally, after movement, the IPv4/v6 mobile node 1806 always transmits once the packet to the foreign IPv6 mobile agent 1809 in accordance with the processing procedure of the Mobile IPv6. Therefore, the foreign IPv6 mobile agent 1809 can receive the IPv6 movement registration request-message 3000 address to the home IPv6 mobile agent 1807 .
The foreign IPv6 movement assistance processing portion 1823 sets the timer (Step 806 ) and waits for the IPv6 movement registration permission message 1601 as the reply of the IPv6 movement registration request message 3000 for a predetermined time (Steps 2507 and 2510 ). Incidentally, the IPv6 movement registration permission message 1601 is encapsulated by IPv4 encapsulation and is transferred by the home IPv6 mobile agent 1807 as described above.
When the IPv6 movement registration permission message 1601 is received within the predetermined time (Step 2507 YES), the foreign IPv6 movement assistance processing portion 1823 updates the registration flag 2142 corresponding to the mobile node, which is previously registered tentatively to the movement assistance management table 1828 , to “real registration” assistance management table 1828 , to “real registration” (Step 2508 ). Further, the home foreign IPv6 movement assistance processing portion 1823 executes IPv4 decapsulation of the IPv6 movement registration permission message 1601 received and transfers this message to the IPv4/v6 mobile node 1806 (Step 2509 ). When the IPv6 movement registration permission message 1601 is not received within the predetermined time (Step 2510 YES), the foreign IPv6 movement assistance processing portion 1823 deletes the information of this mobile node from the movement assistance management table 1828 (Step 2511 ). The foreign IPv6 movement assistance processing portion 1823 completes the processings as described above and thereafter executes them repeatedly.
FIG. 26 is a flowchart showing an example of the processing of the transfer-to-foreign IPv6 mobile agent processing portion 1821 which transfers the IPv6 packet, which other IPv6 node transmits to the IPv6 mobile node or to the IPv4/v6 mobile node 1806 , to the foreign IPv6 mobile agent 1809 existing in the network to which the mobile node moves, at the home IPv6 mobile agent 1807 .
The transfer-to-foreign IPv6 mobile agent processing portion 1821 first judges whether or not the IPv6 packet, which is registered to the mobile node management table 1822 and is addressed to the mobile node, among the IPv6 packets transmitted by the IPv6 node 1804 or other IPv6 nodes (not shown particularly in the drawing) is received (Step 2601 ). If this packet is found received as a result of the judgement, the transfer-to-IPv6 mobile agent processing portion 1821 executes afresh IPv6 encapsulation of this packet (Step 2602 ).
The structure of the IPv6 packet encapsulated by IPv6 encapsulation at this time is the same as the structure 1700 shown in FIG. 17 . The corresponding foreign IPv6 address 1921 inside the movement assistance management table 1822 is set to the foreign IPv6 address 1702 inside the IPv6 header 1701 and the IPv6 address of the home IPv6 mobile agent 1807 of its own is set to the home IPv6 address 1703 .
The transfer-to-foreign IPv6 mobile agent processing portion 1821 judges next whether or not the foreign IPv6 mobile agent IPv4 address 1922 of the corresponding mobile node inside the mobile node management table 1822 is “NULL” (Step 2603 ). If the foreign IPv6 mobile agent IPv4 address 1922 is found “NULL” as a result of the judgement (Step 2603 NO), the transfer-to-foreign IPv6 mobile agent processing portion 1821 judges that the mobile node is moving to the IPv6 network or to the IPv4/v6 network and transmits as such the IPv6 encapsulated IPv6 packet 1700 (Step 2605 ). Incidentally, the processing procedures for executing IPv6 encapsulation of the IPv6 packet and transmitting the packet follow the procedures of the ordinary Mobile IPv6.
If the foreign IPv6 mobile agent IPv4 address 1922 is judged as being other than “NULL” as a result of the judgement (Step 2603 YES), the transfer-to-foreign IPv6 mobile agent processing portion 1821 judges that this mobile node is moving to the IPv4 network, executes further IPv4 encapsulation of the IPv6 packet which has been IPv6 encapsulated already, and transmits it to the foreign IPv6 mobile agent 1809 (Step 2604 ).
FIG. 31 shows the structure of the packet 3100 which is IPv4 encapsulated at this time. As shown in the drawing, this packet has the structure in which the IPv4 header 1401 is added afresh to the IPv6 encapsulated IPv6 packet 1700 shown in FIG. 17 . The value of the corresponding foreign IPv6 mobile agent IPv4 address 1922 inside the mobile node management table 1822 is set to the foreign IPv4 address 1402 inside the IPv4 header 1401 and the value of the IPv4 address of the home IPv6 mobile agent 1807 of its own is set to the home IPv4 address 1403 .
The transfer-to-foreign IPv6 mobile agent processing portion 1821 completes the processing and thereafter executes repeatedly the processing described above.
FIG. 27 is a flowchart showing an example of the processing executed by the transfer-to-other node processing portion 1819 when the IPv6 packet, which the IPv4/v6 mobile node 1806 transfers to other IPv6 node on the foreign IPv4 network, is IPv4 encapsulated and transferred from the foreign IPv6 mobile agent 1809 , to the foreign IPv6 node, in the home IPv6 mobile agent 1807 .
The transfer-to-other node processing portion 1819 first judges whether or not the IPv4 packet addressed to the home IPv6 mobile agent 1807 itself is received (Step 2701 ). If it is found received as a result of judgement (Step 2701 YES), the transfer-to-other node processing portion 1819 then judges whether or not the packet so received is encapsulated by IPv4 encapsulation and transferred by the foreign IPv6 mobile agent 1809 (Step 2702 ). Incidentally, the transfer of the IPv6 packet by the foreign IPv6 mobile agent 1809 is executed by the transfer-to-home IPv6 mobile agent processing portion 1827 inside the foreign IPv6 mobile agent 1809 as will be described later. If it is not found the transferred IPv6 packet as a result of judgement (Step 2702 NO), the transfer-to-other node processing portion 1819 discards this packet (Step 2705 ). If it is the transferred IPv6 packet (Step 2702 YES), the transfer-to-other node processing portion 1819 further judges whether or not the home node of this IPv6 packet is the mobile node registered to the mobile node management table 1822 (Step 2703 ). If it is not found registered as a result of this judgement (Step 2703 NO), the transfer-to-other node processing portion 1819 discards this packet (Step 2705 ). If it is found registered (Step 2703 YES), the transfer-to-other node processing portion 1819 decapsulates this packet by IPv4 decapsulation and transmits it to the foreign IPv6 node (Step 2704 ).
The transfer-to-other node processing portion completes the processing and thereafter executes repeatedly the processing described above.
FIG. 28 is a flowchart showing an example of the processing executed by the transfer-to-home IPv6 mobile agent processing portion 1827 for transferring the IPv6 packet, which is transmitted by the IPv4/v6 mobile node 1806 to other IPv6 node in the foreign IPv6 mobile agent 1809 , to the home IPv6 mobile agent 107 .
The transfer-to-home IPv6 mobile agent processing portion 1827 first judges whether or not the IPv6 packet transmitted from the IPv4/v6 mobile node 106 registered to the movement assistance management table 1828 is received (Step 2801 ). If the corresponding packet is found received as a result of this judgement, the transfer-to-home IPv6 mobile agent processing portion 1827 then judges whether or not the registration flag 2142 of the corresponding mobile node inside the mobile node management table 1828 is “real registration” (Step 2802 ). If it is found the “real registration” as a result of this judgement (Step 2802 YES), the transfer-to-home IPv6 mobile agent processing portion 1827 then encapsulates the IPv6 packet so received by IPv4 encapsulation and transmits it to the home IPv6 mobile agent 1807 (Step 2803 ).
The structure of the IPv6 packet which is IPv4 encapsulated at this time is the same as the structure 1500 shown in FIG. 15 .
The value of the corresponding home IPv6 mobile agent IPv4 address 2141 inside the movement assistance management table 1828 is set to the foreign IPv4 address 1402 inside the IPv4 header 1401 , while own IPv4 address of the foreign IPv6 mobile agent 1809 itself is set to the foreign IPv4 address 1403 .
If the registration flag 2142 is not found the “real registration” as a result of the judgement (Step 2802 NO), the transfer-to-home-IPv6 mobile agent processing portion 1827 discards the packet (Step 2804 ). The transfer-to-home IPv6 mobile agent processing portion 1827 completes the processing and thereafter executes repeatedly the processing described above.
FIG. 29 is a flowchart showing an example of the processing of the transfer-to-mobile node processing portion 1825 which executes the processing for transferring the packet to IPv4/v6 mobile node 1806 when the IPv6 packet, which is transmitted by other IPv6 mobile node to the IPv4/v6 mobile node 1806 by the home IPv6 mobile agent 1807 in the foreign IPv6 mobile agent 1809 , is encapsulated by IPv6 encapsulation, is further encapsulated by IPv4 encapsulation and is transferred.
The transfer-to-mobile node processing portion 1825 first judges whether or not the IPv4 packet addressed to the foreign IPv6 mobile agent 1809 is received (Step 2901 ). If the packet is found received as a result of this judgement (Step 2901 YES), the transfer-to-mobile node processing portion 1825 then judges whether or not the packet so received is the one encapsulated by IPv4 encapsulation and transferred by the home IPv6 mobile agent 1807 (Step 2902 ). Incidentally, the transfer of the IPv6 packet by this home IPv6 mobile agent 1807 is executed by the foreign IPv6 mobile agent processing portion 1821 described above. If the packet is not found as the transferred IPv6 packet as a result of the judgement (Step 2902 NO), the transfer-to-mobile node processing portion 1825 discards this packet (Step 2905 ). If it is found as the transferred packet (Step 2902 YES), the transfer-to-mobile node processing portion 1825 further judges whether or not the foreign node of this IPv6 packet is the mobile node really registered to the movement assistance management table 1828 (Step 2903 ). The IPv6 address of the foreign node is the address of the foreign node contained in the IPv6 packet 1704 . If it not found really registered as a result of the judgement (Step 2903 NO), the transfer-to-mobile node processing portion 1825 discards this packet (Step 2905 ). If it is really registered (Step 2903 YES), the transfer-to-mobile node processing portion 1825 decapsulates this packet by IPv4 decapsulation and then transfers it to the IPv4/v6 mobile node 1806 (Step 2904 ).
The transfer-to-mobile node processing portion 1825 completes the processing and thereafter executes repeatedly the processing described above.
The flow of the processings from FIGS. 22 to 29 described above will be explained hereby with reference to the network system shown in FIG. 18 . When the IPv4/v6 mobile node 1806 exists on the LAN-a 1800 as the home network, the IPv4/v6 mobile node 1806 receives the IPv4 movement detection messages and the IPv6 movement detection message transmitted by the IPv4 mobile agent-a 1805 and the home IPv6 mobile agent 1807 , respectively. Therefore, it is not judged as moving.
When the IPv4/v6 mobile node 1806 has moved to the LAN-b 1801 , the IPv4/v6 mobile agent 1806 receives the messages from the IPv4 mobile agent-b 1808 and the foreign IPv6 mobile agent 1809 , respectively. Therefore, the mobile is judged as having moved to other network. The IPv4/v6 mobile node 1806 transmits the IPv4 movement registration request message and the IPv6 movement registration request message 3000 to the IPv4 mobile agent-a 1805 and to the home IPv6 mobile agent 1807 , respectively, by the IPv4 movement processing portion 1813 and the IPv6 movement processing portion 1815 .
To this IPv6 movement registration request message 3000 are set “ 11 :: 1 ” (home IPv6 mobile agent 1807 ) as the foreign IPv6 address 3002 , “21::30” (assumed as the IPv6 address used afresh on LAN-b 1801 by the IPv4/v6 mobile node 1806 in this embodiment) as the home IPv6 address 3003 , “11::30” (IPv4/v6 mobile node 1806 ) as its own IPv6 address 3005 , and “21::30” as the foreign IPv6 address 3006 .
In this embodiment, the IPv6 packet cannot come out from the LAN-b 1801 beyond the router as described above, but can transmit and receive the IPv6 packet inside the LAN-b 1801 . Therefore, the IPv4/v6 mobile node 1806 can receive the IPv6 movement detection message transmitted by the foreign IPv6 mobile agent 1809 , and can also transmit the IPv6 movement registration request message 3000 to the LAN-b 1801 .
The IPv6 movement registration request message 3000 is once received by the foreign IPv6 mobile agent 1809 . The foreign IPv6 mobile agent 1809 adds the IPv4 header 1401 , in which “10.0.0.1” (home IPv6 mobile agent 1807 ) is set as the foreign IPv4 address 1402 and “20.0.0.1” (foreign IPv6 mobile agent 1809 ) is set as the home IPv4 address 1403 , to the message by its foreign IPv6 movement assistance processing portion 1823 , and transfers the message to the home IPv6 mobile agent 1807 . Thereafter, this message is received by the home IPv6 mobile agent 1807 . After receiving this message, the home IPv6 mobile agent 1807 adds the IPv4 header 1401 , in which “20.0.0.1” (foreign IPv6 mobile agent 1809 ) is set as the foreign IPv4 address 1402 and “10.0.0.1” (home IPv6 mobile agent 1807 ) is set as the foreign IPv4 address 1403 , to the IPv6 movement registration permission message 1601 by its IPv6 movement assistance processing portion 1817 , and transmits this message to the home IPv6 mobile agent 1809 . Receiving this message, the foreign IPv6 mobile agent 1809 decapsulates this message by IPv4 decapsulation by the foreign IPv6 movement assistance processing portion 1823 and transmits decapsulated message to the IPv4/v6 mobile node 1806 .
In consequence, registration of the movement of the IPv4/v6 mobile node 1806 to the home IPv6 mobile agent 1807 is completed. At this time are set “11::30” to the mobile node IPv6 address 20 , “21::30” to the foreign IPv6 address 1921 , and “20.0.0.1” to the foreign IPv6 mobile agent IPv6 address 2140 of the mobile node management table 1822 , as the information of the IPv4/v6 mobile node 1806 . Similarly, “11::30” is set to the mobile node IPv6 address 2140 and “10.0.0.1”, to the home IPv6 mobile agent IPv4 address 2141 of the movement assistance management table 1828 .
When the home IPv6 mobile agent 1807 receives the IPv6 packet transmitted by the IPv6 node 1804 to the IPv4/v6 mobile node 1806 , it adds the IPv6 header 1701 , in which “21::30” is set to the foreign IPv6 address 1702 and “11::1” is set to the home IPv6 address 1703 , to this IPv6 packet by its transfer-to-foreign mobile agent processing portion 1821 , and further adds the IPv4 header 1401 , in which “20.0.0.1” is set to the foreign IPv4 address 1402 and “10.0.0.1” is set to the home IPv4 address 1403 , and transfers the packet to the foreign IPv6 mobile agent 1809 . The packet 3100 is received by the home IPv6 mobile agent 1809 . This mobile agent 1809 decapsulates this packet by IPv4 decapsulation by its transfer-to-mobile node processing portion 1825 and transmits it to the IPv4/v6 mobile node 1806 . The IPv4/v6 mobile node 1806 receives and processes this packet as the IPv6 packet in accordance with the ordinary Mobile IPv6 procedure.
When the home IPv6 mobile agent 1809 receives the IPv6 packet transmitted by the IPv4/v6 mobile node 1806 to the IPv6 node 1804 , on the contrary, it adds the IPv4 header 1401 , in which “10.0.0.1” (home IPv6 mobile agent 1807 ) is set to the home IPv4 address 1402 and “20.0.0.1” (foreign IPv6 mobile agent 1809 ) is set to the home IPv4 address 1403 , to this packet by the transfer-to-home IPv6 mobile agent processing portion 1827 and transmits the packet to the home IPv6 mobile agent 1807 . This IPv4 encapsulated packet 1500 is received by the home IPv6 mobile agent 1807 . The home IPv6 mobile agent 1807 decapsulates this packet by IPv4 decapsulation by its transfer-to-other node processing portion 1819 and transmits the packet to the foreign IPv6 node 1804 . The foreign IPv6 node 1804 receives and processes this packet as the ordinary IPv6 packet.
In the present invention, even when the IPv4/v6 mobile node 1806 moves from the LAN-a 1800 as the IPv4/v6 network to the LAN-b 1801 as the IPv4 network, the IPv4/v6 mobile node 1806 can receive the IPv6 packet transmitted from the IPv4/v6 mobile node 1804 to the IPv4/v6 mobile node 1806 as described above. On the contrary, the existing IPv6 node 1804 can receive the IPv6 packet transmitted by the IPv4/v6 mobile node 1806 to the IPv6 node 1804 .
Further, communication making use of the IPv4 between other nodes and the IPv4/v6 mobile node 1806 can be made by means of the movement assistance by the IPv4 mobile agent-a 1805 supporting the Mobile IPv4 as the existing method and the movement assistance on the IPv4 by the IPv4 mobile agent-b 1808 .
Incidentally, when the IPv4/v6 mobile node 1806 returns from the LAN-b 1801 to the LAN-a 1800 , the IPv4/v6 mobile node 1806 detects this return to the home network by the IPv6 movement processing portion 1815 described above. Then, the IPv4/v6 mobile node 1806 transmits the IPv6 movement registration request message 3000 in which “11::30” is set to its own IPv6 address 3005 and “11::30” which is the same as its own IPv6 address 3005 is set to the home IPv6 address 3006 , to the home IPv6 mobile agent 1807 . Receiving this IPv6 movement registration request message 3000 , the home IPv6 mobile agent 1807 judges that the IPv4/v6 mobile node has returned to the LAN-a 1800 as the home network because its own IPv6 address 3005 inside this message is the same as the foreign IPv6 address 3006 , and then deletes the information about this mobile node inside the mobile node management table 1822 . In consequence, the IPv4/v6 mobile node 1806 can execute communication utilizing the ordinary IPv6. Similarly, since the IPv4/v6 mobile node 1806 reports its return to the LAN-a 1800 to the IPv4 mobile agent-a 1805 in accordance with the processing procedure of the Mobile IPv4 by the IPv4 movement registration request message. Communication utilizing the ordinary IPv4 can be made, too.
In the embodiment described above, the movement of the mobile node between the networks is detected by utilizing the IPv4 movement detection message and the IPv4 detection message, but it is also possible to employ the system construction in which the user of the mobile node indicates by himself to the IPv4 movement processing portion 1813 and to the IPv6 movement processing portion and reports the movement to the IPv4 mobile agent and to the IPv6 mobile agent.
Next, the explanation will be given on the case where the IPv4/v6 mobile node moves from the IPv4/v6 network to the IPv6 network.
A structural example of the network system to which the present invention is applied and a structural example of the mobile agent will be described with reference to FIG. 32 .
As shown in this drawing, the network system according to this embodiment includes a LAN-c 3200 , a LAN-d 3201 and a WAN 1902 connecting the LAN-c 3200 and the LAN-d 3201 by a public line or an exclusive line. On the LAN-c 3200 exist an IPv4 node 3203 executing communication by utilizing only the IPv4, an IPv6 node 3204 executing communication by utilizing only the IPv6, an IPv4/v6 mobile node 1806 executing communication by utilizing both IPv4 and IPv6 and moving between the networks, a home IPv4 mobile agent-c 3206 executing communication by utilizing both IPv4 and IPv6 and assisting the movement of the node, which executes communication by utilizing the IPv4, between the networks, and an IPv6 mobile agent-c 3207 assisting the movement of the node, which executes communication by utilizing the IPv6 in accordance with the Mobile IPv6 procedure, between the networks. On the LAN-d 3201 exist a foreign IPv4 mobile agent 3208 which executes communication by utilizing the IPv4 and IPv6 and assists the movement of the node executing communication by utilizing the IPv4 when this node moves to the LAN-d 3201 , and an IPv6 mobile agent-d 3209 . Here, the IPv4/v6 mobile node 1806 is the same as the one shown in FIG. 18 .
Incidentally, the IPv6 mobile agent-c 3207 functions also as a router handling both of the IPv4 packet and the IPv6 packet and connects the LAN-c 3200 and the WAN 3202 . The IPv6 mobile agent-d 3209 functions also as a router handling only the IPv6 packet and connects the LAN-d 3201 and the WAN 3202 . Therefore, both of the IPv4 packet and the IPv6 packet can go out to =the external networks beyond the routers, whereas only the IPv6 packet can go out from the LAN-d 3201 . Incidentally, transmission/reception itself of the IPv4 packet and the IPv6 packet inside the LAN-c 3200 and the LAN-d 3201 is possible.
In this embodiment, the IP addresses are tabulated below.
IPv4 address
IPv6 address
IPv4 node 3203
“10.0.0.10”
IPv6 node 3204
“11::20”
IPv4/v6 mobile node 1806
“10.0.0.30”
“11::30”
home IPv4 mobile agent 3206
“10.0.0.1”
“11::1”
home IPv4 mobile agent 3208
“20.0.0.1”
“21::1”
The home mobile agent 3206 includes an IPv4 movement assistance portion 3216 which executes communication by utilizing the IPv4 and assists the movement of an IPv4 mobile node (not particularly shown in the drawing) moving between the networks or an IPv4/v6 mobile node 1806 , a mobile node management table 3217 which manages the information of the mobile node that has moved to another IPv4 network or to the IPv4/v6 network, an IPv4 processing portion 3218 which executes processing in accordance with the services offered by the IPv4, a transfer-to-foreign IPv4 mobile agent processing portion 3219 which executes a processing for transferring the IPv4 packet, which is transmitted by other IPv4 node to the IPv4/v6 mobile node 1806 , to a foreign IPv4 mobile agent 3208 , an IPv6 processing portion 3220 which executes processing in accordance with the services offered by the IPv6, a transfer-to-other node processing portion 3221 which executes a processing for transferring the IPv4 packet, which is transferred from the foreign IPv4 mobile agent 3208 and is transferred to the IPv4/v6 mobile node 1806 , to the foreign IPv4 node, and a communication processing portion 3215 which executes transmission/reception control, etc. of the packet to and from the LAN.
The foreign IPv4 mobile agent 3206 comprises a foreign IPv4 movement assistance processing portion 3223 which assists the movement of the IPv4/v6 mobile node 1806 when this node 1806 moves to the network (LAN-d 3201 ) to which the foreign IPv4 mobile agent 3208 belongs, a movement assistance management table 3229 which manages the information of the mobile node, a mobile agent address table 3228 which registers the address information of the home IPv4 mobile agent 3206 , an IPv4 processing portion 3224 which executes a processing in accordance with the services offered by the IPv4, a transfer-to-mobile agent processing portion 3225 which executes a processing for transferring the IPv4 packet, which is transmitted from the IPv4/v6 mobile node 1806 to other IPv4 node, to the home IPv4 mobile agent 3206 , an IPv6 processing portion 3226 which executes a processing in accordance with the services offered by the IPv6, a transfer-to-mobile node processing portion 3227 which executes a processing for transferring the packet, which is transferred from the home IPv4 mobile agent 3206 to the IPv4/v6 mobile node 1806 , to the IPv4/v6 mobile node 1806 , and a communication processing portion 3222 which executes transmission/reception control, etc. of the packet to the LAN.
Here, among the constituent elements of the home IPv4 mobile agent 3206 described above, it is the IPv4 movement assistance processing portion 3216 , the mobile node management table 3217 , the transfer-to-foreign IPv4 mobile agent processing portion 3219 and the transfer-to-other node processing portion 3221 that constitute a characterizing part of the present invention. Among the constituent elements of the foreign IPv4 mobile agent 3208 , the constituent elements according to the present invention are the foreign IPv4 movement assistance portion 3223 , the mobile agent address table 3228 , the movement assistance management table 3229 , the transfer-to-home IPv4 mobile agent processing portion 3225 and the transfer-to-mobile node processing portion 3227 .
FIG. 33 shows an example of the mobile node management table 3217 described above. As shown in the drawing, the mobile node management table 3217 includes a mobile node IPv4 address 3300 as the IPv4 address of the mobile node, a foreign IPv4 address 3301 representing the foreign IPv4 address when the home IPv4 mobile agent 3206 transfers the IPv4 packet address to the mobile node when this mobile node is moving to another IPv4 network or to the IPv4/v6 network, and a foreign IPv4 mobile agent IPv6 address 3302 representing the IPv6 address of the foreign IPv4 mobile agent. Here, “NULL” is set to the foreign IPv4 mobile agent IPv6 address 3302 when the mobile node is moving to the IPv4 network or to the IPv4/v6 network, and the IPv6 address of the foreign IPv4 mobile agent 3208 existing inside the IPv6 network is set when the mobile node is moving to this IPv6 network. Incidentally, though this drawing illustrates the case where entries for a plurality of moving nodes exist, the entry of the mobile node does not exist under the initial state. The updating processing of this table will be later described.
FIG. 34 shows an example of the mobile agent address table 3228 described above. As shown in this drawing, the mobile agent address table 3228 comprises the IPv6 addresses of all the home IPv4 mobile agents existing in the network system (though only the home IPv4 mobile agent 3206 on the LAN-c 3200 is shown in this embodiment), the home IPv4 mobile agent IPv6 address 340 . 0 as the IPv4 address and the home IPv4 mobile agent IPv4 address 3401 . This table is set by a manager, etc.
FIG. 35 shows an example of the movement assistance management table 3229 described above. As shown in this drawing, the movement assistance management table 3229 includes a mobile node IPv4 address 3500 as the IPv4 address of the IPv4/v6 mobile node 1806 , a home IPv4 mobile agent IPv6 address 3501 as the IPv6 address of the home IPv4 mobile agent 3206 existing inside the home network of the mobile node, and a registration flag 3502 representing whether the entry is “tentative registration” or “real registration”. Though this drawing illustrates the case where entries for a plurality of mobile nodes exist, the entry for the mobile node does not exist in this table under the initial state. The updating processing of this table will be described later.
In the construction described above, the processing operations of the IPv4/v6 mobile node 1806 , the home IPv4 mobile agent 3206 and the foreign IPv4 mobile agent 3208 , and handling of each table described above, when the IPv4/v6 mobile node 1806 has moved from the LAN-c 3200 as the IPv4/v6 network to the LAN-d 3201 as the IPv6 network, will be explained in detail.
FIG. 36 is a flowchart showing an example of the processing of the IPv4 movement assistance processing portion 3216 for executing the assistance processing of the IPv4 mobile node (not particularly shown in the drawing) or the IPv4/v6 mobile node 1806 , between the networks.
The IPv4 movement assistance processing portion 3216 first judges whether or not the message transmission request message for detecting the IPv4 movement is received (Step 3601 ). When this message is found received as a result of this judgement (Step 3601 YES), the IPv4 movement assistance processing portion 3216 transmits the IPv4 movement detection message (Step 3602 ). Next, the IPv4 movement assistance processing portion 3216 judges whether or not the IPv4 movement registration request message is received (Step 3603 ). Here, FIG. 42 shows the structure of this IPv4 movement registration request message 4200 . As shown in the drawing, the IPv4 movement registration request message 4200 includes an IPv4 header 1401 and an IPv4 data 4201 . The IPv4 header 1401 includes a foreign IPv4 address 1402 and a home IPv4 address 1403 , and the IPv4 address of the home IPv4 mobile agent 3206 is set to the foreign IPv4 address 1402 while the IPv4 address of the IPv4/v6 mobile node 1806 is set to the home IPv4 address 1403 . The IPv4 data 4201 includes the IPv4 address 4202 as own IPv4 address of the node transmitting this message and the foreign IPv4 address 4203 as the foreign address when the IPv4 packet address to this mobile agent is transferred. The same address as the IPv4 address 4202 is set to the foreign IPv4 address 4203 when the IPv4/v6 mobile node 1806 returns to the LAN-c 3200 as the home network. Incidentally, this message is transmitted by the IPv4 movement processing portion 1813 inside the IPv4/v6 mobile node 1806 explained already with reference to FIG. 22 .
When the IPv4 movement registration request message 4200 is found received as a result of judgement (Step 3603 YES), the IPv4 movement assistance processing portion 3216 further judges whether or not this movement registration request is acceptable (Step 3604 ). When it found unacceptable as a result of this judgement (Step 3604 NO), the IPv4 movement assistance processing portion 3216 transmits an IPv4 movement registration rejection message as a rejection reply message to the IPv4 movement registration request message 4200 to the mobile node (Step 3605 ). If it is found acceptable (Step 3604 YES), the IPv4 movement assistance processing 3600 then compares its own address 4202 inside the message with the foreign IPv4 address 4203 (Step 3606 ).
If own IPv4 address 4202 and the foreign IPv4 address 4203 are found the same as a result of the judgement described above (step 3606 YES), the IPv4 movement assistance processing portion 3216 judges that the mobile node has returned to the home network and detects the information of the corresponding mobile node inside the mobile node management table 3217 (Step 3607 ). The IPv4 movement assistance processing portion 3216 transmits the IPv4 movement registration permission message as the permission reply message of registration of the IPv4 movement registration request message 4200 to the mobile node (Step 3611 ).
If own IPv4 address 4202 and the foreign IPv4 address 4203 are found different as a result of the judgement (Step 3609 NO), the IPv4 movement assistance processing portion 3216 further judges whether or not the IPv4 movement registration request message 4200 received is the message which is encapsulated by IPv6 encapsulation and transmitted by the foreign IPv4 mobile agent 3208 (Step 3608 ). Incidentally, this IPv6 encapsulation of the IPv4 movement registration request message 4200 by the foreign IPv4 mobile agent 3208 is executed by the foreign IPv4 movement assistance processing portion 3223 inside the later-appearing IPv4 mobile agent 3208 . Receiving this IPv4 movement registration request message 4200 which is IPv6 encapsulated in this way, the home IPv4 mobile agent 3206 decapsulates the message by IPv6 decapsulation by its IPv6 processing portion 3220 and delivers the message to the IPv4 movement assistance processing portion 3216 . IPv6 decapsulation by this IPv6 processing portion is one of the services offered by the existing IPv6.
If the result of the judgement represents that the message is not IPv6 encapsulated and is not transferred (Step 3608 NO), the IPv4 movement assistance processing portion 3216 judges that the mobile node has moved to another IPv4 network or to the IPv4/v6 network and sets the information of this mobile node to the mobile node management table 3217 (Step 3609 ). At this time, the value of the foreign IPv4 address 4203 inside the received IPv4 movement registration request message 4200 is set to the foreign IPv4 address 3301 inside the mobile node management table 3217 and “NULL” is set to the foreign IPv4 mobile agent IPv6 address 3302 . Then, the IPv4 movement assistance processing portion 3216 transmits the IPv4 movement registration permission message to the mobile node (Step 3611 ).
If the message is found the one that is IPv6 encapsulated and is transferred as a result of the judgement (Step 3608 YES), the IPv4 movement assistance processing portion 3216 judges that the mobile node has moved to the IPv6 network and sets the information of this mobile node to the mobile node management table 3217 (Step 3610 ). At this time, the value of the foreign IPv4 address 4203 inside the transferred IPv4 movement registration request message 3300 is set to the foreign IPv4 address 3301 inside the mobile node management table 3217 , and the value of the home IPv6 address inside the IPv6 added to the transferred IPv4 movement registration request message 4200 is set to the foreign IPv4 mobile agent IPv6 address 3302 . The IPv4 movement assistance processing portion 3216 encapsulates and transmits the IPv4 movement registration permission message as the reply to the mobile node (Step 3612 ).
The data structure of the IPv6 encapsulated IPv4 movement registration permission message 4301 at this time is shown in FIG. 43 . As shown in the drawing, this message has the construction in which the IPv6 header 1701 is added to the IPv4 movement registration permission message 4301 . The foreign IPv4 mobile agent IPv6 address 3302 registered to the mobile node management table 3217 is set to the foreign IPv6 address 1702 inside the IPv6 header 1701 and own IPv6 address of the home IPv4 mobile agent 3206 itself is set to the home IPv6 address 3003 .
The IPv4 movement assistance processing portion 3216 completes the processing and thereafter repeats the processing described above.
FIG. 37 is a flowchart showing an example of the processing of the foreign IPv4 movement assistance processing portion 3223 for executing the movement assistance processing of the IPv4/v6 mobile node 1806 between the networks in the foreign IPv4 mobile agent 3208 .
The foreign IPv4 movement assistance processing portion 3223 first judges whether or not the message transmission request message for detecting the IPv4 movement is judged (Step 3701 ). If this message is found received as a result of this judgement (Step 3701 YES), the foreign IPv4 movement assistance processing portion 3223 transmits the IPv4 movement detection message (Step 3702 ). Next, the foreign IPv4 movement assistance processing portion 3223 judges whether or not the IPv4 movement registration request message 4200 is received (Step 3703 ). If this message is found received as a result of the judgement (Step 3703 YES), the foreign IPv4 movement assistance processing portion 3223 tentatively registers the information of this mobile node to the movement assistance management table 3229 (Step 3704 ). At this time, the value of own IPv4 address 4202 inside the received IPv4 movement registration request message 14200 is set to the foreign IPv4 address 3500 inside the mobile node management table 3229 and the value of the home IPv4 mobile agent IPv6 address 3400 , that corresponds to the foreign IPv4 address 1402 inside the IPv4 movement registration request message 4200 , is set to the home IPv4 mobile agent IPv6 address 3501 by looking up the mobile agent address table 3228 . Further, “tentative registration” is set to the registration flag 3502 . The foreign IPv4 movement assistance processing portion 3223 encapsulates by IPv6 encapsulation the IPv4 movement registration request message 4200 so received, and transfers the message to the home IPv4 mobile agent 3206 (Step 3705 ).
The structure of the IPv6 encapsulated IPv4 movement registration request message 4200 at this time is shown in FIG. 44 . As shown in this drawing, the message 4400 has the construction in which the IPv6 header 1701 is added to the IPv4 movement registration permission message 4200 shown in FIG. 42 . The home IPv4 mobile agent IPv6 address 3501 registered to the movement assistance management table 3229 is set to the foreign IPv6 address 1702 inside the IPv6 header 1701 , and own IPv6 address of the foreign IPv4 mobile agent 3208 is set to the home IPv6 address 1703 .
Incidentally, the IPv4/v6 mobile node 1806 always transmits after its movement the packet to the foreign IPv4 mobile agent 3208 in accordance with the processing procedure of the Mobile IPv4. Therefore, the foreign IPv4 mobile agent 3208 can receive the IPv4 movement registration request message 4200 .
The foreign IPv4 movement assistance processing portion 3223 sets the timer (Step 3706 ) and waits for the IPv4 movement registration permission message 4301 as the reply to the IPv4 movement registration request message 4200 for a predetermined time (Steps 3707 and 3710 ). By the way, this IPv4 movement registration permission message 4301 is encapsulated to the IPv6 encapsulated message and is transmitted by the home IPv4 mobile agent 3206 as described above.
If the IPv4 movement registration permission message 4301 is received within the predetermined time (Step 3707 YES), the foreign IPv4 movement assistance processing portion 3223 updates the registration flag 3502 corresponding to the mobile node, which has been tentatively registered to the mobile agent management table 3229 previously, to “real registration” (Step 3708 ). Further, the foreign IPv4 movement assistance processing portion 3223 decapsulates by IPv6 decapsulation the IPv6 header 1701 added to the received IPv4 movement registration permission message 4301 and transfers the message to the IPv4/v6 mobile node 1806 (Step 3709 ). If the IPv4 movement registration permission message 4301 is not received within the predetermined time (Step 3701 YES), the foreign IPv4 movement assistance processing portion 3223 deletes the information of this mobile node from the movement assistance management table 3229 (Step 3711 ).
The foreign IPv4 movement assistance processing portion 3223 completes the processing and thereafter repeats the processing described above.
FIG. 38 is a flowchart showing an example of the processing of the transfer-to-foreign IPv4 mobile agent processing portion 3219 which executes the processing for transferring the IPv4 packet transmitted by other IPv4 node to the IPv4 mobile node (not particularly shown in the drawing) or to the IPv4/v6 mobile agent 1806 to the foreign IPv4 mobile agent 3208 existing in the foreign network of the mobile node, in the home IPv4 mobile agent 3206 .
The transfer-to-foreign IPv4 mobile agent processing portion 3219 first judges whether or not the IPv4 packet addressed to the mobile node registered to the mobile node management table 3217 among the IPv4 packets transmitted by the IPv4 node 1804 and other IPv4 nodes (not particularly shown in the drawing) is received (Step 3801 ). If the corresponding packet is found received as a result of this judgement (Step 3801 YES), the transfer-to-foreign IPv4 mobile agent processing portion 3219 then judges whether or not the foreign IPv4 mobile agent IPv6 address 3302 of the corresponding mobile node inside the mobile node management table 3217 is “NULL” (Step 3802 ). If the foreign IPv4 mobile agent IPv6 address 3302 is found “NULL” as a result of the judgement (Step 3802 NO), the transfer-to-foreign IPv4 mobile agent processing portion 3219 judges that the mobile node is moving to the IPv4 network or to the IPv4/v6 network, and encapsulates the IPv4 packet so received by IPv4 encapsulation and transmits the encapsulated packet (Step 3804 ). Incidentally, the processing procedure for effecting IPv4 encapsulation and transferring the packet follows the ordinary Mobile IPv4.
If the foreign IPv4 mobile agent IPv6 address 3302 is found to be other than “NULL” as a result of the judgement (Step 3802 YES), the transfer-to-foreign IPv4 mobile agent processing portion 3219 judges that the mobile node is moving to the IPv6 network, encapsulates the received IPv4 packet by IPv6 encapsulation and transmits the encapsulated packet to the foreign IPv4 mobile agent 3208 (step 3803 ).
The structure of the IPv6 encapsulated IPv4 packet at this time is shown in FIG. 45 . This packet has the construction in which the IPv6 header 1701 is added afresh to the IPv4 packet 4501 . The value of the foreign IPv4 mobile agent IPv6 address 3302 inside the mobile node management table 3217 is set to the foreign IPv6 address 1702 inside the IPv6 header 1701 , and own IPv6 address of the home IPv4 mobile agent 3206 is set to the home IPv6 address 1703 .
The transfer-to-foreign IPv4 mobile agent processing portion 3219 completes the processing and thereafter executes repeatedly the processing described above.
FIG. 39 is a flowchart showing an example of the processing of the transfer-to-other node processing portion 3221 which executes the processing for transferring the packet to the IPv4 node when the IPv4 packet transmitted by the IPv4/v6 mobile node 1806 to other IPv4 node on the foreign IPv6 network is encapsulated by IPv6 encapsulation and transferred by the foreign IPv4 mobile agent 3208 , in the home IPv4 mobile agent 3206 .
The transfer-to-other node processing portion 3221 first judges whether or not the IPv6 packet address to the home IPv4 mobile agent 3208 itself is received (Step 3901 ). If the packet is found received as a result of this judgement (Step 3901 YES), the transfer-to-other node processing portion 3221 then judges whether or not the packet is the IPv4 packet that is encapsulated and transferred by the foreign IPv4 mobile agent 3208 (Step 3902 ). Incidentally, this transfer of the IPv4 packet by the foreign IPv4 mobile agent 3208 is executed by the transfer-to-IPv4 mobile agent processing portion 3225 inside the later-appearing foreign IPv4 mobile agent 3208 . If the packet is not found the transferred IPv4 packet as a result of the judgement (Step 3902 NO), the transfer-to-other node processing portion 3221 discards this packet (Step 3905 ). If it is found the transferred IPv4 packet (Step 3902 YES), the transfer-to-other node processing portion 3221 further judges whether or not the foreign node of this IPv4 packet is the mobile node registered to the mobile node management table 3217 (Step 3903 ). If it is not found registered as a result of the judgement (Step 3903 NO), the transfer-to-other node processing portion 3221 discards this packet (Step 3905 ). If it is found registered (Step 3903 YES), the transfer-to-other node processing portion 3221 decapsulates this packet by IPv6 decapsulation and transmits it to the foreign IPv4 node (Step 3904 ).
The transfer-to-other node processing portion 3221 completes the processing and thereafter repeats the processing described above.
FIG. 40 is a flowchart showing an example of the processing of the transfer-to-home IPv4 mobile agent processing portion 3225 which executes the processing for transferring the IPv4 packet, which the IPv4/v6 mobile node 1806 transmits to other IPv4 nodes, to the home IPv4 mobile agent 3206 in the foreign IPv4 mobile agent 3208 .
The transfer-to-home IPv4 mobile agent processing portion 3225 first judges whether or not the IPv4 packet, which is registered to the movement assistance management table 3229 and is transmitted by the IPv4/v6 mobile agent 1806 , is received (Step 4001 ). If the corresponding packet is found received as a result of this judgement (Step 4001 YES), the transfer-to-home IPv4 mobile agent processing portion 3225 then judges whether or not the registration flag 3502 of the corresponding mobile node inside the mobile node management table 3229 is “real registration” (Step 4002 ). If the registration flag is found the “real registration” as a result of the judgement (Step 4002 YES), the transfer-to-home IPv4 mobile agent processing portion 3225 encapsulates the received IPv4 packet by IPv6 encapsulation and transmits it to the home IPv4 mobile agent 3206 (Step 4003 ).
The IPv4 packet subjected to IPv6 encapsulation at this time has the same structure as the structure shown already in FIG. 45 . The value of the corresponding home IPv4 mobile agent IPv6 address 3501 inside the movement assistance management table 3229 is set to the foreign IPv6 address inside the IPv6 header 1701 and the IPv6 address of the foreign IPv4 mobile agent 3208 itself is set to the foreign IPv6 address 1703 .
If the registration flag 3502 is not found the “real registration” as a result of the judgement (Step 4002 NO), the transfer-to-home IPv4 mobile agent processing portion 3225 discards this packet (Step 4004 ). The transfer-to-home IPv4 mobile agent processing portion 3225 completes the processing and thereafter repeats the processing described above.
FIG. 41 is a flowchart showing an example of the processing of the transfer-to-other mobile node processing portion 3227 which executes the processing for transferring the packet to the IPv4/v6 mobile node 1806 when the IPv4 packet transmitted by other IPv4 node to the IPv4/v6 mobile node 1806 by the home IPv4 mobile agent 3206 is encapsulated by IPv6 encapsulation and is transferred, in the foreign IPv4 mobile agent 3208 .
The transfer-to-mobile node processing portion 3227 first judges whether or not the IPv6 packet addressed to the foreign IPv4 mobile agent 3208 itself is received (Step 4101 ). If it is found received as a result of this judgement (Step 4101 YES), the transfer-to-mobile node processing portion 3227 then judges whether or not the received packet is the IPv4 packet which is IPv6 encapsulated and transferred by the home IPv4 mobile agent 3206 (Step 4102 ). Incidentally, this transfer of the IPv4 packet by the home IPv4 mobile agent 3206 is executed by the home IPv4 movement assistance processing portion 3219 described above. If the packet is not the transferred IPv4 packet as a result of the judgement (Step 4102 NO), the transfer-to-mobile node processing portion 3227 discards this packet (Step 4105 ). If it is the transferred IPv4 packet (Step 4102 YES), the transfer-to-mobile node processing portion 3227 further judges whether or not the node of this IPv4 packet is the mobile node registered really to the movement assistance management table 3229 (Step 4103 ). If the node is not found registered really (Step 4103 NO) as a result of this judgement, the transfer-to-mobile node processing portion 3227 discards the packet (Step 4105 ). If it is found registered really (Step 4103 YES), the transfer-to-mobile node processing portion 3227 decapsulates this packet by IPv6 decapsulation and transfers the packet to the IPv4/v6 mobile agent 1806 (Step 4104 ).
The transfer-to-other node processing is completed and thereafter the processing described above is repeatedly executed.
The flow of the processings shown in FIG. 22 and in FIGS. 36 to 41 will be explained with reference to the network system shown in FIG. 32 . When the IPv4/v6 mobile node 1806 exists on the LAN-c 3200 as the home network, the IPv4/v6 mobile node 1806 is judged as not moving because it receives the IPv4 movement detection message and the IPv6 movement detection message transmitted by the home IPv4 mobile agent 3206 and the IPv6 mobile agent-c 3207 , respectively.
When the IPv4/v6 mobile node 1806 has moved to the LAN-d 3201 , the IPv4/v6 mobile node 1806 is judged as having moved to another network because it receives the IPv4 movement detection message and the IPv6 movement detection message transmitted by the foreign IPv4 mobile agent 3208 and the IPv6 mobile agent-d 3209 , respectively. Then, the IPv4/v6 mobile node transmits the IPv4 movement registration request message 4200 and the IPv6 movement registration request message 3000 by means of the IPv4 movement processing portion 1813 and the IPv6 movement processing portion 1815 to the home IPv4 mobile agent 3206 and to the IPv6 mobile agent-c 3207 , respectively.
To this IPv4 movement registration request message 4200 are set “10.0.0.1” (home IPv4 mobile agent 3206 ) as the foreign IPv4 address 1402 , “10.0.0.30”, as its own IPv4 address 3202 and “20.0.0.30” (as the foreign IPv4 address which the IPv4/v6 mobile node 1806 acquires from the foreign IPv4 mobile agent 3208 in the foreign LAN-d 3201 in this embodiment), as the transfer IPv4 address.
In this embodiment, the IPv4 packet cannot come out from the LAN-d 3201 beyond the router to the external network as described above but can transmit/receive the IPv4 packet inside the LAN-d 3201 . Therefore, the IPv4/v6 mobile node 1806 can receive the IPv4 movement detection message transmitted by the foreign IPv4 mobile agent 3208 and can also transmit the IPv4 movement registration request message 4200 to the LAN-d 3201 .
This IPv4 movement registration request message 4200 is once received by the foreign IPv4 mobile agent 3208 . The foreign IPv4 mobile agent 3208 adds the IPv6 header 1701 , in which “11::1” (home IPv4 mobile agent 3206 ) is set as the foreign IPv6 address 1702 and “21::1” (foreign IPv4 mobile agent 3208 ) is set as the home IPv6 address 1703 , to this message- 4200 by means of its foreign IPv4 movement assistance processing portion 3223 , and transfers the message to the home IPv4 mobile agent 3206 . Thereafter, this message is received by the home IPv4 mobile agent 3206 . After receiving this message, the home IPv4 mobile agent 3206 adds the IPv6 header 1701 , in which “21::1” (foreign IPv4 mobile agent 3206 ) is set as the foreign IPv6 address 1702 ) and “11::1” (home IPv4 mobile agent 3208 ) is set as the home IPv6 address 1703 , to the IPv4 movement registration permission message 4301 by means of its IPv4 movement assistance processing portion 3216 , and transfers the message to the foreign IPv4 mobile agent 3208 . Receiving this message, the foreign IPv4 mobile agent 3208 decapsulates the message by IPv6 decapsulation by its foreign IPv4 movement assistance processing portion 3223 and transmits the message to the IPv4/v6 mobile node 1806 .
In this way, registration of the movement of the IPv4/v6 mobile node 1806 to the home IPv4 mobile agent 3206 is completed. At this time, “10.0.0.30” is set as the information of the IPv4/v6 mobile node 1806 to the mobile node IPv4 address 3300 of the mobile node management table 3217 , “20.0.0.30” is set to the foreign IPv4 address 3301 and “21::1” is set to the foreign IPv4 mobile agent IPv6 address 3302 . Further, “10.0.0.30” is set to the mobile node IPv4 address 3500 of the movement assistance management table 3229 and “μl::1” is set to the foreign IPv4 mobile agent IPv6 address 3501 .
Receiving the IPv4 packet transmitted from the IPv4 node 3203 to the IPv4/v6 mobile node 1806 , the home IPv4 mobile agent 3206 adds the header 1701 , in which “21::1” (foreign IPv4 mobile agent 3208 ) is set to the foreign IPv6 address 1702 and “11::1” (home IPv4 mobile agent 3206 ) is set to the home IPv6 address 1703 , to the IPv4 packet by means of the transfer-to-foreign IPv4 mobile agent processing portion 3219 , and transfers the packet to the foreign IPv4 mobile agent 3208 . The IPv6 encapsulated packet is received by the foreign IPv4 mobile agent 3208 . The foreign IPv4 mobile agent 3208 decapsulates this packet by IPv6 decapsulation by its transfer-to-node processing portion 3227 and transmits it to the IPv4/v6 mobile node 1806 . The IPv4/v6 mobile node 1806 receives and processes this packet as the IPv4 packet in accordance with the procedure of the ordinary Mobile IPv4.
When the IPv4/v6 mobile node 106 receives the IPv4 packet transmitted to the IPv4 node 3203 , on the contrary, the foreign IPv4 mobile agent 3208 adds the IPv6 header 1701 , in which “11::1” (home IPv4 mobile agent 3206 ) is set to the foreign IPv6 address 1702 and “21::1” (foreign IPv4 mobile agent 3208 ) is set to the home IPv6 address 1703 , to the packet by means of the transfer-to-home IPv4 mobile agent processing portion 3205 and transmits the packet to the home IPv4 mobile agent 3206 . The IPv6 encapsulated packet is received by the home IPv4 mobile agent 3206 . The home IPv4 mobile agent 3206 decapsulates this packet by IPv6 decapsulation by its transfer-to-other node processing portion 3221 and then transmits it to the foreign IPv4 node 3203 . The IPv4 node 3203 receives and processes this packet as the ordinary IPv4 packet.
According to the present invention described above, even when the IPv4/v6 mobile node 1806 moves from the LAN-c 3200 as the IPv4/v6 network to the LAN-d 3201 as the IPv6 network, the IPv4/v6 mobile node 1806 can receive the IPv4 packet transmitted by the IPv4 node 3203 to the IPv4/v6 mobile node 1806 . On the contrary, the existing IPv4 node 3203 can receive the IPv4 packet transmitted by the IPv4/v6 mobile node 1806 to the IPv4 node 3203 .
Communication by making use of the IPv6 between other node and the IPv4/v6 mobile node 1806 can be made by the assistance of movement by the IPv6 mobile agent-c 3207 supporting the IPv6 and by the assistance of movement of the node in the IPv6 by the IPv6 mobile agent-d 3209 .
Incidentally, when the IPv4/v6 mobile node 1806 returns from the LAN-d 3201 to the LAN-c 3200 , the IPv4/v6 mobile node 1806 detects its return to the home network by the IPv4 movement processing 1813 described already. Then, the IPv4/v6 mobile node 1806 transmits the IPv4 movement registration request message, in which “10.0.0.30” is set to its own address 4202 and “10.0.0.30” having the same address as its own IPv4 address 4202 to the foreign IPv4 address 4203 , to the home IPv4 mobile agent 3206 . Receiving this IPv4 movement registration request message 4200 , the home IPv4 mobile agent 3206 judges that the IPv4/v6 mobile node 1806 has returned to the LAN-c 3200 as the home network because its own IPv4 address 4202 in the message has the same address as that of the foreign IPv4 address 4203 , and then deletes the information of this mobile node in the mobile node management table 3217 . As a result, the IPv4/v6 mobile node 1806 can make communication by utilizing the ordinary IPv4. Similarly, the IPv4/v6 mobile node 1806 reports the return to the LAN-c 3200 by the IPv6 movement registration request message 3000 to the IPv6 mobile agent-c 3207 , too, in accordance with the processing procedure of the Mobile IPv6. Therefore, communication utilizing the ordinary IPv6 can be made, as well. | A mobile node moves from a first IP (Internet Protocol) network to a second IP network in a network system in which the first IP network capable of executing communication in accordance with both first and second kinds of IPs and the second IP network capable of executing communication in accordance with only the first kind of IP are connected with each other. When the mobile node communicates a message with other nodes on the first network after its movement accordance with the second kind of IP, a header for the movement containing both home and foreign addresses of the first kind in IP is added to a header containing home and foreign addresses in the second kind of IP, and put to the message, is added. The message to which the movement header is thus added is used for the communication between a first mobile agent on the first network and a second mobile agent on the second network, or between the mobile node and the first mobile agent. | 7 |
This application is a divisional application of U.S. Ser. No. 08/233,486, filed on Apr. 26, 1994, now U.S. Pat. No. 5,489,812 which is a divisional application of U.S. Ser. No. 07/890,455, filed on May 29, 1992, and now issued as U.S. Pat. No. 5,351,412.
FIELD OF THE INVENTION
The present invention relates to a method of making a semiconductor integrated micro-actuator capable of achieving fine positioning in the X and Y directions.
BACKGROUND OF THE INVENTION
The attempt to compact existing mechanical systems has a rather long history. However, a technology has recently drawn attention to integrate a mechanical system of a size that varies from several micrometers to several hundreds of micrometers. It comprises a plurality of components such as sensors, actuators, and electronic circuits, and preferably use the IC (Integrated Circuit) fabrication technique called MEMS (Micro Electro Mechanical Systems). Sensors in the field of MEMS are fast reaching the level of practical use, mainly as acceleration sensors using transducers, as described in the paper by H. Seidel, et al, "Capacitive Silicon Accelerometer with Highly Symmetrical Design", Transducers '89 Lecture No. B10.4, June 1989, and as pressure sensors, described in the paper by K. Ikeda, et al, "Silicon Pressure Sensor Integrates Resonant Strain Gauge On Diaphragm", Transducers '89 Lecture No. B4.3, June 1989. However, the study of micro actuators has just begun. As an example of a micro actuator, an ultrasonic motor using a piezoelectric element is actively studied at present.
OBJECTS AND SUMMARY OF THE INVENTION
The positioning accuracy of detectors in an optical recording or magnetic recording system may be in the future of the order of submicrons. It requires that the positioning device used for the system have an operating range of several hundreds of micrometers in the X and Y directions, respectively, that its size does not exceed several millimeters and, finally, that it get a quick response. Positioning meeting the above requirement can be achieved with a conventional micro ultrasonic motor.
Accordingly, it is an object of the present invention to provide a device capable of achieving fine positioning.
It is another object of the present invention to achieve micro positioning of the order of 100-μm in the X and Y directions.
It is a further object of the present invention to arrange, on the same surface, micro actuators of the order of micrometers using semiconductor fabrication techniques and capable of surface-driving the group of actuators with a driving source.
The micro positioning device of the present invention, as described hereinafter comprises: a substrate, a plurality of micro actuators arranged on the substrate, and a moving member placed on the micro actuators. Each micro actuator consists of a driving section for applying a driving force to excite vertical motion on the substrate, and a mechanism for converting vertical motion into rotational motion, displaced in the horizontal direction. The structure of the micro actuator which is the basic component of the present invention differs in terms of the type of driving force used, as will be shown hereinafter.
The foregoing and other objectives, features and advantages of the present invention will become clearer from the detailed descriptions of the preferred embodiments of the invention, as illustrated in the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an embodiment of the micro actuator 60 structure according to the present invention;
FIG. 2 shows a second embodiment of the micro actuator structure in accordance with the present invention;
FIG. 3 shows still another embodiment of the micro actuator structure of the present invention;
FIG. 4 shows the fabrication process of the micro actuator in FIG. 2;
FIG. 5 shows the fabrication process of the micro actuator in FIG. 3;
FIGS. 6 and 7 show the operating principle of the present invention; and
FIG. 8 shows a schematic structural diagram of the micro positioning device according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows the structure of a micro actuator using vibration force as its driving force. A piezoelectric element (PZT) 2 is bonded or laminated to substrate 1, (e.g. a silicon wafer). Aluminum electrodes 3A and 3B are deposited on the PZT 2, and a contact pin 4 is formed across the aluminum electrodes. Although polyimide is used for contact pin 4 in this particular embodiment, it may be possible to use resist which allows the pin to have a large aspect ratio.
FIG. 2 shows the structure of a micro actuator 40 using Coulomb's force as the driving force. Operation of the micro actuator using Coulomb's force will be further described hereinafter. FIGS. 4(a)-4(e) show the fabrication process steps for the driving section 45 of the micro actuator 40. Note that the driving section 45 as shown upon completion in FIG. 4(e) excludes contact pin 4, as illustrated in FIG. 2.
A silicon nitride film is first deposited on a silicon wafer 1. As shown in FIG. 4(a), the silicon nitride film is etched to form a desired pattern 5. Then, steam is applied to silicon wafer 1 to oxidize the etched section 8 to produce the structure shown in FIG. 4(b). Next, additional silicon nitride is deposited on the silicon wafer 1 to form a first silicon nitride film 5', a polycrystal silicon film 6 is deposited on the first silicon nitride film 5', and a second silicon nitride film 5" is deposited on the polycrystal silicon film 6. Following deposition of these layers 5', 6 and 5", the central portion 50 of the layers 5', 6, 5" is etched to a predetermined size to form the structure of FIG. 4(c). Next, the portion 8 is etched at the central section 50 so as to form an opening through the central section 50 to the portion 8, as shown in FIG. 4(d). Subsequently, the silicon wafer 1 is oxidized and oxide films 7 are formed, as shown in FIG. 4(e). The micro actuator 40 with the structure shown in FIG. 2 is obtained by forming the contact pin 4 on the driving section 45 thus fabricated.
FIG. 3 shows the structure of a micro actuator 70 using fluid pressure (e.g., air pressure) as its driving force. In this case, the driving section 75 of the micro actuator 70, which excludes the contact pin 4 illustrated in FIG. 3, is fabricated using the process steps shown in FIGS. 5(a)-5(d).
Silicon nitride films 11 are deposited on both sides of a first silicon wafer 1A. A desired pattern is then formed by lithographic techniques and followed by selective etching. Similarly, a silicon nitride film 11 is deposited on both sides of a second silicon wafer 1B and a desired pattern is likewise formed by lithographic techniques. It is then etched as shown in FIG. 5a in a manner similar to the process used for the first silicon wafer 1A. An anisotropic etching is then applied to the first silicon wafer 1A to form an air channel 9 (FIG. 5b). Likewise, anisotropic etching is also applied to the second silicon wafer 1B in a manner similar to the process used for the first silicon wafer 1A. In it, a wedge shaped pattern acting as a valve for fluid such as air is formed at the central portion of the second silicon wafer 1B (FIG. 5b).
Referring to FIG. 5c, the silicon nitride film 11, which was deposited on the first and second silicon wafers 1A and 1B produced by the process shown in FIGS. 5a and 5b, is removed. Finally, the first and second silicon wafers 1A and 1B are thermally bonded to form a driving section (FIG. 5d). Circle 10 in FIG. 5d (enclosed by a broken line) is shown as the portion that functions as a valve for feeding air. Thus, a micro actuator with the structure shown in FIG. 3 is obtained. Finally, a contact pin 4 is formed on the driving section to complete the structure.
Following is a description of the operating principle of the present invention FIGS. 6 and 7!.
FIG. 6 shows a schematic diagram that illustrates the operating principle when Coulomb's force is used as the driving force. Similarly, FIG. 7 shows a schematic diagram that illustrates the operating principle when air pressure is used as the driving force.
First, the operating principle of the present invention will be described referring to FIG. 6. When no voltage is applied between the silicon wafer 1 and the silicon nitride films 5A and 5B, contact pin 4 remains static as its initial position (FIG. 6a). When a voltage is applied between silicon wafer 1 and silicon nitride film 5A, the silicon nitride film 5A is lowered by Coulomb's force in the direction shown by the arrow 12. As a result, a difference in height occurs between silicon nitride films 5A and 5B forcing the contact pin 4 placed between silicon nitride films 5A and 5B to tilt towards the right, while the end of the contact pin moves in the direction of the arrow 13 (FIG. 6b).
When a voltage is applied to silicon nitride films 5A and 5B, the films are lowered in the direction of the arrow 12 and 15 until they reach the same height. Thereafter, contact pin 4 returns to its upright position. (Note: it is important that silicon nitride films 5A and 5B are first lowered from their initial position). Thus, the end of contact pin 4 moves in the direction of the arrow 14 (FIG. 6c).
When the voltage applied to the silicon nitride film 5A is removed, the silicon nitride film 5A attempts to move back in the direction of the arrow 17, owing to a spring force inherent to its structure. As a result, the contact pin 4 moves to a position which is a mirror image of the position shown in FIG. 6b. Thus, the end of the contact pin moves in the direction of the arrow 16 (FIG. 6d). When the voltage applied to silicon nitride film 5B is removed, silicon nitride film 5B tries to move back in the direction of the arrow by a force inherent to its structure. Therefore, the end of the contact pin 4 moves in the direction of the arrow 13 (FIG. 6e).
As previously described, the micro actuator is operated by the operating sequence shown in FIGS. 6b through 6d, forcing the end of contact pin 4 to rotate in a clockwise rotation.
The operating principle of the present invention is further explained by referring to FIG. 7. First, a voltage is applied to the silicon wafer 1B to close the wedge-typed air valve V. By applying Coulomb's force, the air-valve V adheres to the lower silicon wafer 1B. Air is supplied to the air channel 8 by an air pump (not shown) after closing the air valve V. Air, however, is not supplied to the right air channel A 2 but only to the left air channel A 1 (as a result of the air valve V being closed). Thus, the upper silicon wafer 1A is raised in the direction of the arrow 32 by air pressure in air channel A 1 . A difference in height occurs between the silicon wafers 1A and 1B and the end of the contact pin 4 moves in the direction of the arrow 30 (FIG. 7a). When the voltage applied to the silicon wafer 1B is turned off, the air valve V opens, and air is supplied in the direction of the arrow 34 to both air channels A 1 and A 2 . As a result, the silicon wafers 1A and 1B move in the direction of the arrow by air pressure in channels A 1 and A 2 . Since a difference in height occurs between the silicon wafers 1A and 1B, the contact pin 4 returns to its upright position, although its height differs from its initial height. Thus, the end of the contact pin 4 moves in the direction of the arrow 36 (FIG. 7b).
When a voltage is applied to the silicon wafer 1B, the wedge-type air valve V closes, air is released from the left air channel A1, and silicon wafer 1A is lowered in the direction of the arrow 44. As a result, because a difference in height occurs between the silicon wafers 1A and 1B, the contact pin 4 tilts and its end moves in the direction of the arrow 42 (FIG. 7c). Finally, when the air valve V, which had been closed in the step illustrated in FIG. 7c reopens, air supplied to the right air channel A 2 is released. The silicon wafer 1B descends in the direction of the arrow until silicon wafers 1A and 1B reach the same height, at which time contact pin 4 returns to its initial position with the end of contact pin 4 moving in the direction of the arrow 46 (FIG. 7d).
As previously described, when air pressure is used as the driving force, the micro actuator follows a sequence similar to the one described in FIG. 6, and the end of the contact pin 4 rotates clockwise.
Though the operating principle of micro actuators using Coulomb's force and air pressure as driving forces are described above, the same holds true for a micro actuator that uses vibrational force as its driving force.
A micro positioning device can be structured by arranging the above micro actuators on the same surface as an array and arranging a moving member on the micro actuator array. FIG. 8 shows a schematic diagram of an X-axis-directional structure of a micro positioning device according to a further embodiment of the present invention. This embodiment uses vibrational force as its driving force.
In FIG. 8, a first voltage is applied to a first aluminum electrode 3A and a second voltage is applied to a second aluminum electrode 3B. The first and second voltages have a predetermined phase difference. Therefore, PZT 2 bonded on the silicon wafer 1 moves vertically or in the direction of the arrow with the predetermined phase difference. The vertical motion intermittently causes a difference in height between the first aluminum electrode 3A and the second aluminum electrode 3B. The end of contact pin rotates due to the intermittent height difference in the direction of the arrow. Therefore, the moving member 15 (e.g. a roller) placed on a plurality of contact pins 4, moves horizontally by motion of the contact pins 4. When the end of contact pin 4 moves leftward by driving an actuator, the actuator to the left side of the above actuator is activated, the end of the contact pin 4 moves rightward, and the roller 15 is pressed rightward by the actuator. Thus, the roller 15 is positioned at a certain balanced point.
In the above embodiment, only positioning in the X-axis direction was described. However, the same is also true for positioning in the Y-axis direction. Additionally, in the above embodiment, the driving forces use vibrational force. However, the positioning operation is the same as that of the above embodiment even if other types of driving forces are used, and even if the structure of the micro positioning device of the present invention differs.
As described above, the micro actuator of the present invention use a direct driving system directed by a plurality of actuators. It attains a high positioning accuracy even for open loop control. It also attains positioning within an operating range of several tens to several hundreds of micrometers in the X and Y directions. It is thus possible to obtain a compact and lightweight miniature micro positioning device.
While the invention has been particularly shown and described with reference to preferred embodiments thereof it will be understood by those skilled in the art that the foregoing and other changes in the form and details may be made therein without departing from the spirit and the scope of the invention. | A method of fabricating a semiconductor integrated microactuator device that includes the steps of: bonding or laminating a driving element to a substrate for generating a vertical motion, and coupling a conversion element to the driving element for converting the vertical motion into rotational motion. The method can be effectively used for micro-actuators that utilize Coulomb's force, vibration, and fluid pressure as their driving force. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a U.S. National Phase entry under 35 U.S.C. §371 of International Application PCT/AU2008/000244, filed Feb. 26, 2008, and which claims priority under the Paris Convention to Australian patent application No. 2007900955, filed Feb. 26, 2007, the entire contents of each of which are incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to computer generated digitally encoded electric waveforms used in the implementation of novel financial systems and methods. In the description contained herein, the invention is primarily concerned with data process methods and systems for computing property index values, automated property valuations, and financial derivative values.
COPYRIGHT NOTICE
This document contains material which is subject to copyright. The applicant as copyright owner has no objection to the reproduction of this patent document in its entirety as it appears in the Patent Office files or records, but otherwise reserves all copyright rights whatsoever.
BACKGROUND ART
Residential and commercial real estate are the world's two largest tangible asset classes. Residential real estate accounts for the bulk of the average household's wealth portfolio. Understanding the pattern of price movements in residential and commercial real estate is therefore of vital importance to households, policy-makers, regulators, businesses and investors. Historically, accurate measures of the time-series changes in the risk and return characteristics of residential and commercial real estate assets have been extremely hard to come by. In turn, the valuation of individual property assets using automated and/or statistical property valuation systems has been a hazardous practice. Finally, the development of financial derivative and futures contracts based on proxies for the residential and commercial real estate asset class have been hindered by poor index design.
The present specification is primarily concerned with two core areas: 11 (1) unique data collection methods and processing systems for quantifying, measuring, evaluating and ultimately outputting estimates of time-series risk and return movements in residential and commercial real estate portfolios; and, 11 (2) unique data collection methods and processing systems for quantifying, measuring, evaluating and ultimately outputting estimates of the values of various derivative financial instruments that enable capital markets participants to secure synthetic investment exposures to residential and commercial property assets, or to synthetically hedge against the risk inherent in the ownership of such assets, amongst other things.
In reviewing the background art, two key areas of focus are: (1) the extant evidence surrounding the development of property indices; and (2) the extant evidence on the use of index-linked property derivatives and other types of financial contracts;
1. Data processing, evaluation, and index-output systems
Historically, there has been a great deal of public criticism from economists, commentators, regulators and policymakers about the integrity of the existing sources of property price performance.
Ian Macfarlane, the former Governor of the Reserve Bank of Australia said:
“Housing . . . is an extremely important asset class for most people, yet the information we have on prices is hopeless compared with the information we have on share prices, bond prices, and foreign exchange rates . . . . It really is probably the weakest link in all the price data in the country so I think it is something that I would like to see resources put into.”
The criticism has a common basis: that the dynamics of the price performance measures do not accurately reflect the dynamics of the true property values, for a combination of three possible reasons:
i. The sample of property sales used to construct the measures is insufficient or biased, ii. The sample of property sales used to construct the measures is obtained a significant time after the actual transactions have occurred and thus the measures represent past, not present conditions, and iii. The statistical measures calculated from the sample of property sales are not accurate or meaningful representations of changes in value of the population of properties from which the sample is taken.
GENESIS OF THE PRESENT INVENTION
The genesis of the present invention is a desire to develop a portfolio of data processing, evaluation, and index-output arrangements to comprehensively address these deficiencies. Such new data processing, evaluation, and index-output systems will be commercially useful to any individual or organisation interested in examining four key issues:
1. Estimating residential and commercial property valuations over time; 2. Measuring historical residential and commercial property returns in a given suburb, postcode, region, city or nationally over any given period of time (eg, months or years); 3. Measuring historical residential and commercial property risks in a given suburb, postcode, region, city or nationally over any given period of time (eg, months or years); and 4. Forecasting future residential and commercial property returns or risks in a given suburb, postcode, region, city or nationally over any given period of time (eg, months or years).
In particular, the data processing, evaluation, and index-output systems will almost certainly be of interest to the following clientele:
Businesses which own their premises Mortgage lenders; Mortgage insurers; Participants in the media; Commonwealth, State and Local Governments; Universities; Economists and consultants; Investment bankers; Listed property investors; Property developers; Building materials manufacturers or suppliers; Existing or potential home owners; Existing or potential investment property owners; Potential home/investment property buyers; Mortgage brokers; Financial planners.
SUMMARY OF THE INVENTION
In accordance with a first aspect of the present invention there is disclosed a method of generating a digitally encoded electric signal which represents a real estate property index, said method comprising the steps of:
i. inputting into a data store of a computing apparatus real estate data comprising property data, price data and time of sale data representing historical real estate sales transactions in a predetermined real estate market, ii. using said computer apparatus to manipulate said real estate data to group same into consecutive triple times based on said time of sale data, iii. using said computer apparatus to generate a transform function using said manipulated data with two time dummy variables corresponding to two consecutive time periods respectively bounded by the triple consecutive times, iv. using said computer apparatus to extract the coefficients of the two time dummy variables of said transform function for said two consecutive time periods, v. adding said two extracted coefficients in said computer apparatus to generate a transformed growth rate from the first to the last of said triple times, and vi. generating said digitally encoded electric signal which represents said index from said transformed growth rate by calculating the reverse transform function thereof.
In accordance with a second aspect of the present invention there is disclosed a method generating a real estate property index, said method comprising the steps of:
i. inputting into a data store of a computing apparatus real estate data comprising property data, price data and time of sale data representing historical real estate sales transactions in a predetermined real estate market, ii. using said computer apparatus to manipulate said real estate data to group same into consecutive triple times based on said time of sale data, iii. using said computer apparatus to generate a transform function using said manipulated data with two time dummy variables corresponding to two consecutive time periods respectively bounded by the triple consecutive times, iv. using said computer apparatus to extract the coefficients of the two time dummy variables of said transform function for said two consecutive time periods, v. adding said two extracted coefficients in said computer apparatus to generate a transformed growth rate from the first to the last of said triple times, and vi. generating said index from said transformed growth rate by calculating the reverse transform function thereof.
In accordance with a third aspect of the present invention there is disclosed a system for generating a digitally encoded electric signal which represents a real property index, said system comprising:
i. a data store into which is input real estate data comprising property data, price data and time of sale data representing historical real estate transactions in a predetermined real estate market, ii. data manipulation means connected to said data store to manipulate said real estate data into groups of consecutive triples times based on said time of sale data, iii. generation means connected to said data manipulation means to generate a transform function using said manipulated data with two time dummy variables corresponding to two consecutive time periods respectively bounded by a triple consecutive times, iv. coefficient extraction means connected with said generation means to extract the coefficients of the two time dummy variables of said transform function for said two consecutive time periods, v. adding means connected to said coefficient extraction means to add said two extracted coefficients to generate a transformed growth rate from the first to the last of said triple times, and vi. reverse transfer function generation means connected to said adding means to generate said digitally encoded electric signal which represents said logarithmic growth rate by calculating the reverse transform of said transformed growth rate.
The transform function is preferably a logarithmic function.
Conventional property indices afford a summarised measure of the price performance of the assets in a market through time. In the context of the market for residential real estate, however, there are a number of complicating factors. Identifying the accurate and unbiased estimation of movements in real estate prices is of real practical importance, since understanding this market helps to explain macroeconomic patterns of aggregate wealth and investment behaviour. This is because real estate is, with the exception of human capital, the largest and most widely held asset class in the world. It follows that few real tradeable assets are as pervasive to every social niche as real estate. Yet, for it its size, it is one of the most poorly understood, measured and managed assets.
While the most general concept of real estate encompasses all buildings, developed land and vacant land, residential real estate can be defined as that component of developed urban land that is designated for housing. The other primary real estate market is commercial, which is divided into office, retail, industrial and (often) hotels. To an extent, all property i markets are driven by common broad macroeconomic movements. In particular, both business cycles and long term socio-economic factors, such as migration and employment, exhibit a causal relation between price and volume movements in the different real estate markets. Similarly, there exist parallels between the influences of microeconomic factors across real estate markets. The commercial real estate markets compete with the residential for the same parcels of land which are supplied by government bodies through zoning mechanisms. Furthermore, because real estate is tied to its location (a characteristic termed in the literature as “spatial fixity” or “spatial immobility”) it is likely that demographic and socio-economic factors of an area will be reflected in both residential and commercial real estate markets.
In spite of the broad analogies between real estate markets, it is important to delineate measurement and analysis of the residential from the non-residential sector since a number of issues, while universal to all property markets (and one might argue for all asset markets in general), are magnified in the context of the housing market. These include liquidity, heterogeneity, transparency, and the availability and timeliness of data.
In a perfect market of homogenous goods, indices are designed to capture price movements and are generally implemented by a relatively straightforward algorithm. The residential real estate market, however, has a number of characteristics that render standard techniques used in other markets flawed. The fundamental difficulty with estimating price trends in housing is that unlike other financial assets, houses are extremely heterogeneous and rarely traded, and there is no centralised market for their transactions. Since the vast majority of homes are not transacted in a given time period, it remains an uncertain and difficult methodological problem to translate recent transaction data into an accurate measure of the value of the overall housing stock. These issues—liquidity, heterogeneity, transparency, and data integrity—will in turn be discussed for the remainder of this section.
In most housing markets around the world, less than 10 percent of the total population of residential properties turns over every year on average. For the Australian market, it is estimated that only around 6 percent of the entire housing stock turns over every year. A corollary to this is that holding periods for housing assets are relatively high. The average holding period for houses in Australia for example is over 6 years. FIG. 1 illustrates the cumulative distribution of tenure patterns for the Australian housing market and that of Sydney, Melbourne and Brisbane separately. Around 50 percent of the housing stock turns over within 5 years for all markets, but the remaining 50 percent takes up to 25 years to turn over.
The high costs of trade in residential real estate markets dissuade active trading, and that the extensive role played by governments at both State and Federal levels in the market for residential real estate exacerbates these costs. The influence of governments in housing markets is particularly acute through tax legislation. The costs associated with home-ownership in Australia are illustrated in FIG. 2 .
The housing market is highly heterogeneous. On top of the illiquidity issue, this further complicates empirical analysis of the residential real estate market. The composition across regions of the characteristics of each house is highly disparate, and that consequently, the urban housing market is not one perfect market but a set of interrelated submarkets. Even within these sub-markets, however, the characteristics of housing units can differ considerably. In particular, the spatial immobility of housing means that location alone is a point of difference between houses. Consumers of housing (home-buyers) face a limited ability to substitute between houses with differing characteristics. Substitution is also limited from an analytical perspective. In a liquid market, the same or at least very similar assets are expected to be observed in multiple time periods, and so heterogeneity is not such a concern. Conversely, in an illiquid market of homogenous assets, assets of interest may be substituted between periods without capturing changes in quality.
The third issue related to the performance of residential real estate is transparency. Transparency refers to the ability of buyers and sellers to observe information related to the supply and demand sides of the market, the transactions that are executed and other market participants, both contemporaneously and historically. Residential real estate markets, however, are typically highly decentralised; an observation made in recent reports by the Reserve Bank of Australia (RBA) and International Monitory Fund (IMF). Furthermore, information relating to transactions of properties is subject to privacy legislation. These factors restrict the efficient dissemination of information and contribute to the high transaction costs of trading residential real estate. Because information is not as efficiently diffused through the real estate market, as it is thought other markets, the random arrival of buyers and sellers increases the probability of a transaction price not representing worth. This further complicates the measurement of the empirical performance of residential real estate markets.
The availability of detailed cross-sectional and historical data is needed to accurately measure and to assess price performance in residential real estate markets. This is because of the heterogenous nature of housing. Such characteristic information is required in order to control for qualitative differences between properties. However, at least for Australia, the data currently available is insufficient for this purpose. The RBA identifies the lack of timeliness of data as the most important issue to measuring aggregate prices in residential real estate markets. The RBA argues that as a result of the decentralisation of the market and the poor transparency of trades, most data is obtained from State Government Land Titles Offices which are recorded up to several months after settlement. As a frustrating consequence, the most recent data is not equivalent to contemporaneous market movements, and empirical analysis of current movements is delayed.
The relative sizes of the Australian residential and commercial property markets (and its components) are shown in FIG. 3 .
Residential property accounted for $176B or 86% of transactions by $ value in Australia 2006. The $29B of commercial property transactions for 2006 were divided amongst its 4 categories as:
Office
$13B
Retail
$6B
Industrial
$7B
Hotel
$3B
Further, the commercial property market is multi-tiered. Properties valued at approximately $20M and above have such strongly individual characteristics and sell sufficiently rarely that they are really only amenable to appraisal based methods (which include recent neighbouring sales), whereas an understanding of the dynamics of the market in commercial properties in the sub $20M tier is amenable to a transactions based index approach.
There is a perceived need and opportunity for commercial property derivatives based on transactions prices. A futures market for commercial property could, at least in theory, greatly increase the efficiency of the real estate industry by allowing greater specialization among the various players in the traditional real estate investment business, including investors, developers, property owners, fund managers, mortgage lenders, and others. Index return swaps could address longstanding problems with real estate investment, such as high transactions costs, lack of liquidity, inability to sell “short”, and difficulty comparing investment returns with securities such as stocks and bonds.
Hither to repeat sales based index similar to a residential property index has been proposed but has not been commercially implemented.
This specification discloses hedonic, transaction based commercial indices, which are significantly different in both method and construction to repeat sales indices.
Conceptual Framework
A general form of a house price index incorporates three components: current transactions prices, cross-sectional characteristic details and historical prices. This model can be written as
p i , t = ∑ t = 1 T [ D i , t 1 α t + ∑ j = 1 K X i , j , t β j , t + D i , t 2 X i , t γ t ] + ɛ i , t ( 1.1 )
where p i,t is the price of house i sold in time t, D i,t 1 is a vector of dummy variables for each time period, X i,t is a vector of attribute features for house i at time t, D i,t 2 is a vector of dummy variables equal to 1 if property i has sold previously and zero otherwise, ε i,t is the random noise associated with the sale of house i at time t, and α t , β t , and γ t are regression coefficients to be estimated. These parameters represent, respectively, the index value attributable to period t, the implicit value at time t for the k cross-sectional attribute features, and the expected appreciation to properties that have a second sale at time t.
This method is immediately adaptable to modelling price movements in commercial real estate.
The hedonic-regression is a method that attempts to overcome the issue of compositional bias associated with median price measures. The premise for this lies in hedonic theory which suggests that the relative value of a composite good—such as a house—is the sum of its components. Thus, by decomposing the sample of houses into their various structural and location attributes, the differences in these across houses can be controlled.
The term hedonic was first applied to this concept in relation to a similar multivariate regression technique to automobile pricing. Movements in agricultural produce have been modelled via a multiple regression model. An academic application of the hedonic technique to housing was made by in the early 1970's. Virtually simultaneously, the United States Census Bureau constructed the first government-produced hedonic index for housing. However, the hedonic index methodology is only recently becoming increasingly accepted by government bodies, especially statistical agencies, such as the Australian Bureau of Statistics and the German Bureau of Statistics.
Analysis of the hedonic process can be separated into two concepts: the “composition stage” and the “estimation stage.”
The methods associated with the composition stage of hedonic index formulation are reviewed first.
The composition stage deals with the approaches to constructing indices from the hedonic function.
The actual specification of the hedonic function is the subject matter of the estimation stage. Consequently, the following discussion assumes a correctly specified hedonic function.
There are two general approaches for composing hedonic indices from the hedonic function:
i. time dummy variable regressions, and ii. index number methods.
The time dummy-variable hedonic regression is the method used in the early hedonic studies. This method estimates a hedonic regression with dummy-variables for each time period. The quality-controlled cumulative growth rate attributable to the time period is then captured by the coefficients of the time dummy variables.
Specifically, the dummy variable regression technique controls for the various characteristics and qualitative features of a property that determine price, using a multivariate pooled regression, in which dummy variables are used to represent the time period of each sale.
This can be represented in the semi-logarithmic form as
log P i ( t ) = α ( t ) + ∑ j = 1 N β j X i , j + ∑ t = 1 T λ ( t ) D ( t ) + ɛ i ( t ) ( 1.2 )
where P i (t) is the selling price of property i at time t, α(t) is the intercept term, X is a vector of the N hedonic attributes included in the model, β j is the regression coefficient reflecting the implicit price of j th attribute, λ(t) estimates the cumulative growth rate to time t, D(t) is a set of dummy variables equal to 1 if the property sold in time-period t and zero otherwise, and ε i (t) is the random variation in price of property i at time t unaccounted for by the other terms.
The main advantage to the dummy-variable index over other hedonic index composition techniques is its relatively uncomplicated computation. However, it is also this directness of the model which constitutes the method's main problem. By pooling observations across time periods, the implicit attribute values, or “shadow prices,” are held constant. The theoretical structure of the market clearing mechanisms for housing does not suggest that it can be assumed either that at a given market period the relative implicit prices for attributes are the same, or that across market periods the implicit characteristics prices for the same packages of housing services remain constant. This is to be expected since consumer preferences for attributes, designs and locations evolve through time, and the characteristics and amenities of neighbourhoods change.
The stability of attribute values in a pooled hedonic pricing model for residential housing can be tested by comparing coefficient estimates to those achieved from separate time hedonic models. Using comparative F-statistic analysis one finds inconclusive support for the null hypothesis that coefficient values are equal across time periods. This suggests that the implicit prices of attributes are not too divergent through time. However, strong empirical evidence for time-varying asset prices thus the null hypothesis that implicit prices remain constant over time has been rejected. In a study of the underpinning assumption of constant implicit prices in hedonic (and repeat-sales) modelling estimates were compared from a restricted hedonic function to those from a model where slope coefficients can change every year. The results are robust across alternative hedonic specifications using data for two cities in California. Sales data using two time period sub-samples, 1993 to 1998 and 1999 to 2005 from Sydney, Melbourne and Brisbane, supports this finding and rejects the null hypothesis of constant coefficient estimates.
The estimation stage refers to the actual specification of the hedonic function. To achieve efficient unbiased estimates using the hedonic method, it is necessary to correctly specify the regression. In the hedonic literature, this issue of specification is widely acknowledged yet unresolved. This is in part because the appropriate specification of a hedonic function may be data-set specific. In specifying a regression function, three essential components one identified, namely: functional form, choice of variables, and form of the variables.
Functional form refers to the nature of the relationship between the explanatory variables and dependent variable. The hedonic function is typically estimated by ordinary least squares (OLS). This estimation method, however, requires linearity in the parameters. However, an estimated regression function may be non-linear in its variables. Through transformations of variables created by using logarithms, exponentials, reciprocals, transcendental functions, polynomials, products, ratios, and so on, the ‘linear’ model can be tailored to any number of situations. This array of choice, however, is a mixed blessing. While a seemingly endless combination of functional forms may be used to capture the true relationship between property prices and property characteristics, there is a lack of theory guiding the choice of functional form (or even variables to include) which is a significant problem encountered in hedonic modelling.
Non-linearities in the relationship between house prices and the prices and quantities of housing attributes can be incorporated. The logic behind this derives as a result of the bundling of housing characteristics. The hedonic function can be analysed as the optimal consumption set of packages of characteristics. While a constraint applies to the unbundling of this package of characteristics, the relationship will be non-linear. In other words, housing is a Gestalt good; the whole is potentially worth more than the sum of the parts. Because housing is a tie-in sale of a set of characteristics, (location, if nothing else) the relationship between price and its determining variables is likely to be nonlinear. Empirical hedonic studies typically specify a double-log or semi-log form of hedonic regression. These are motivated by the theoretical advantages outlined above, or the empirical advantage of logarithmic functions of minimising the effect of heteroskedasticity in data. The semi-logarithmic model, in which the dependent variable is transformed as in equation (1.2), is a constant growth model. This is particularly appropriate for time series analysis, since the parameter coefficients reflect the constant growth rate
However, the functional form decision is one that needs to be based on empirical results, suggesting that the optimal hedonic specification will vary between different localities. Monte Carlo experiments can be used to determine what specification will be most precise. Empirically, for the same data, it is possible that no functional specification is consistently preferred. This finding creates some doubt as to the appropriateness of restricting data to the same function across time and space.
A non-parametric regression technique can be introduced to the hedonic-regression. This has the advantage of being able to estimate house price indices across regions and time without assuming the same functional form. Specifically, a locally weighted regression uses a function, similar to a moving average, to estimate the regression surface, ideally at every point in the sample. It is a costly and computationally-expensive method. There is another recent non-parametric regression technique, the loess. This method centres the hedonic price function estimates at fixed points, such as the beginning or ending period. This allows for more flexible estimation and is an improved method for controlling for the effect of quality evolution—the change in the overall quality of housing stock—on price movements.
Commercially Available Data Processing and Index-Output Systems
In Australia, there are a number of crude property indices available from both official sources, such as the Australian Bureau of Statistics (ABS), and private providers, such as CBA/HIA, REIA, APM and Residex. These indices vary in quality and coverage.
A brief summary of the different index products provided in Australia is shown below:
Provider
Index Product
REIA
Median Price Index
CBA/HIA
Median Price Index
ABS
Stratified Median Price Index
Residex
Repeat Sales Index
APM
Stratified Median Price Index
IPD
Appraisal Based Commercial Property Price Index
To date, there is no extant precedent for the following data processing, evaluation, and index-output systems:
There has never been a median price, stratified median price, repeat-sales, hedonic or hybrid index construction systems that has made use of real-time property sales data collection methods that resolve the timeliness issue that afflicts all property indices—ie, an index that relates to property sales reported, for example, in the week prior to the index publication rather than lagged sales that actually occurred 2-3 months ago; There has never been a ‘double adjacent-period’ hedonic price index which specifies a direct method of transforming the hedonic inputs, such that the transformations may vary over time. The double adjacent period method allows the production of indicative and fixed values for each period, which are a pre-requisite for a tradable index; There has never been a “hedonic accumulation index”, which combines a hedonic imputation method for estimating rental yields with a hedonic capital gains index to derive a total return (ie. accumulation) index There has never been a property price index specifically designed for derivatives trading, which both Tracks investment returns on a diversified property portfolio Tracks periodic rebalancing of a diversified property portfolio to reflect changing market composition
Data processing, evaluation, index-output, and derivative estimation systems
Investing in residential and commercial real estate has hitherto been principally limited to the buying and selling of tangible property. This is due to the inherent constraints associated with transacting real estate. These include high transaction costs, market illiquidity, execution delays and the inability to short-sell units of property. The net result of this is that to date property markets, unlike other financial markets, are subject to severe pricing inefficiencies and key stakeholders in the market face a greater risk than players in other markets from the lack of opportunities to hedge their exposure.
Real estate holdings have the risk of downward price movements. This fact can have an adverse effect upon the net worth of many companies and individuals who have significant portions of their assets accounted for by real estate holdings. This includes builders, developers, mortgage insurers and owners of properties.
Another party impacted by downward movements in real estate prices is the banking industry, since the purchase of real estate is typically financed with money borrowed from these institutions. The likelihood of borrower default and the loss in the event of default are both increased in a falling property market. Banks will be adversely affected by borrowers who default on their loan. The only hedging mechanism that is really available to such lenders is financial futures or options contracts based upon interest rates, which are only indirectly associated with, or indicative of, real estate values.
Home-owners, business property direct investors in residential real estate and indirect investors via residential or commercial real estate (being security over loans) would all benefit greatly from financial instruments that would permit them to hedge the risk of their property investment. Indeed, several academics published papers in the early 1990's identifying the need for such hedging instruments, and generally calling for the availability of cash-settled futures or options contracts based upon unspecified indices of real estate prices. This demonstrates a long felt want for such indices.
In addition to providing an effective tool for hedging against tangible residential and commercial real estate investment, derivatives in residential and commercial real estate would enable investors to synthetically invest in real estate. These investors may be interested in diversifying their institutional and individual investment portfolios to include real estate, which is known to have small positive or negative correlations with other financial markets such as equities and bonds. Alternatively, they may be seeking to balance their real estate portfolio by investing in real estate in a separate geographic region to their current investment's location. The current method of investing in real estate requires the actual purchase of the physical piece of property. However, as already described the selling and buying of real estate is an inherently inefficient and expensive process, making it exceedingly difficult for investors to efficiently invest capital in desirable real estate holdings. Furthermore, to truly diversify a real estate investment portfolio, one would need to purchase different types of real estate in many different geographic markets. The costs of executing such a real estate investment strategy, however, would be exorbitant. Moreover, once purchased, such real estate holdings need to be maintained and managed which further increases these costs. Similarly a portion of a specific property cannot be sold, only the entirety of the property.
Derivatives markets are markets for contractual instruments whose performance is determined by how some underlying instrument or asset performs. Derivatives contracts exist between two parties—a buyer and seller—in which each party has certain rights and obligations. Derivatives contracts typically state a price and the terms of agreement. The contracts may be either standardised, as is required for listed derivative contracts, or non-standardised as is permitted in over the counter markets. Non-standardised contracts may be preferable when an investor is looking to gain, or hedge, exposure to a specific aspect of the market. There are various types of derivative contracts: options, forward contracts, futures contracts, swaps and related derivatives.
An option is a contract between a buyer and seller that gives the buyer the right, but not the obligation, to purchase or sell some underlying asset at a later data at a price agreed upon today. The option buyer pays the option seller (or ‘writer’) a sum of money known as a ‘premium.’ The option seller is bound to sell or buy according to the contract terms if and when the option buyer so desires. Two categories of options exist: calls and puts. An option to buy some underlying asset is known as a call, while an option to sell some underlying asset is known as a put.
A forward contract is an agreement between a buyer and seller to purchase some underlying asset at a latter date at a price agreed upon today. On the face of it, a forward contract sounds like an option however the two are distinguished by the rights of the respective parties: an option carries the right, but not the obligation to go through with the transaction. If the price of the underlying asset moves such that exercising the option is not as favourable as directly buying or selling in the underlying market, the option holder may decide to forgo buying or selling at a fixed price. On the other hand, the two parties in a forward contract incur the obligation to ultimately buy and sell the underlying asset.
A futures contract is an agreement between a buyer and seller to buy or sell something at a future date. The contract trades on a futures exchange and is subject to a daily settlement procedure. Futures contracts are very similar to forwards, but are standardised and typically developed in liquid markets.
A swap is a contract in which two parties agree to exchange future cashflows. For example, party A may agree to pay to party B a fixed return on some notional amount, while party B agrees to pay to party A a return equal to that of a property index. Alternatively, party A may agree to pay to party B a return equal to the prevailing market interest rate plus or minus a margin on the notional amount.
In 2006, the Chicago Mercantile Exchange launched the first residential real estate futures market for 10 US cities based on the Standard & Poors Case/Shiller repeat-sales residential property indices. Trading volumes have been very thin for a number of reasons relating as follows to the data processing systems and the index construction and design:
The reporting of the property sales used in the Standard & Poors Case/Shiller repeat-sales index are 2-3 months delayed from the actual date of the property sales; The Standard & Poors Case/Shiller repeat-sales indices are subject to nontrivial historical revisions as new data are added to the index; The Standard & Poors Case/Shiller repeat-sales indices suffer from numerous biases associated with the use of repeat-sales methodologies, including the following:
Repeat sales indices address the compositional change issue by conditioning on a given house (ie, a given characteristics configuration). However, this may not be enough to entirely eliminate changes in quality of housing from the price index as even a given house changes over time. This is due to the fact that some houses depreciate while other owners improve and renovate their homes. These two competing influences can lead to either deterioration or improvement in the quality of the dwelling over time. In a recent conference on real estate price indices, convened by the OECD and the IMF, the consensus seemed to emerge that the bias in repeat sales price indexes was likely to be in the upward direction. This implicitly reflects the belief that renovations and improvements outweigh the gradual erosion in value due to wear-and-tear; The repeat-sales model assumes that the quality of the asset is constant through time, which is rarely the case (eg, renovations, depreciation); Because only properties that transacted more than once are included in the sample, a significant number of observations (eg, up to 80%) are completely discarded; Within this set of more frequently traded properties there is potential significant sample selectivity bias (eg, apartments or poorer quality properties may trade more or less frequently than detached or better quality homes); Another drawback of the repeat-sales method is revision volatility, which creates instability in the index. Revision volatility is the tendency for previously estimated index values for prior quarters to change as new data arrives. This is a major drawback for the repeat-sales which relies heavily on data from previous quarters; A final source of bias is that the repeat-sales approach does not allow for changes in the “implicit” price of particular housing attributes over time. Each property attribute has its own price determined by the demand for and supply of that attribute (eg, number of bathrooms, bedrooms, pools, tennis courts). Moreover, with the repeat-sales method, it is difficult to control for atypical maintenance or capital improvements made during the period between a sale and a resale of a given property. Thus, quality may not be truly held constant when using this technique. In theory, estimation models should test whether attribute coefficients change over time. Yet when one limits the analysis to repeat-sales price data, these tests are not possible.
To date, there is following desirable index-linked derivatives have not been provided or foreshadowed:
An exchange traded property index derivative based on a hedonic or an imputed hedonic data processing and index-output system; An over-the-counter property index derivative based on ay of an adjacent-period hedonic, imputed hedonic house price data processing and index-output system; An exchange traded property index derivative based on any of an adjacent-period hedonic, imputed hedonic house price data processing and index-output system which incorporates both capital gain and rental yield information; An over-the-counter property index derivative based on any of an adjacent-period hedonic, imputed hedonic house price data processing and index-output system which incorporates both capital gain and rental yield information; An exchange traded property index derivative based on the use of real-time property sales data processing systems that resolve the timeliness issue that afflicts all property indices—ie, an index that relates to property sales reported, for example, in the week prior to the index publication.
BRIEF DESCRIPTION OF THE DRAWINGS
The preferred embodiments of the present invention will be described with reference to the drawings in which:
FIG. 1 is a graph illustrating the distribution of housing tenancy in Australia and its major cities,
FIG. 2 is a pie chart illustrating the cost of home ownership in Australia,
FIG. 3 is a graph illustrating Australian property sales in the year 2006,
FIG. 4 is a graph of the estimated hedonic house price index of the example,
FIG. 5 is a block diagram of a computer system on which embodiments of the present invention can be implemented, and
FIG. 6 is a representation of a digitally encoded electric waveform.
DATA PROCESSING AND INDEX-OUTPUT SYSTEMS
In accordance with a first aspect of the present invention there is disclosed a computer implemented data processing, evaluation and index-output system for accurately measuring the real-time risk, return and valuation changes in residential real estate assets over time. In summary, the new data processing index-output systems that have not been disclosed in the prior art are:
1. A double adjacent-period hedonic capital gain price index; 2. A double adjacent-period hedonic accumulation price index; 3. A convexity adjustment to make the indices track the value of a diversified property portfolio. 4. A method of periodically rebasing the indices in order to cater for the dual needs of having the index represent investment returns on a property portfolio, while allowing portfolio rebalancing to track market composition.
It is to be understood that each of the above four (4) data processing index-output systems applies equally to the construction of both residential and commercial property indices.
The adjacent-period approach, attempts to minimise the potentially biasing effect of restricted coefficients in the dummy-variable model. This model is different from the dummy-variable method in that it pools data only from consecutive time periods.
The adjacent period approach is further modified to a triplet of periods, allowing construction of a tradable index, with indicative and final (locked) figures produced each period, to cater for the rate of data flow.
The data are grouped into triplets of consecutive periods. For each of these “double adjacent-period” subsets of data, a hedonic function
log P i ( t ) = α ( t ) + ∑ j = 1 N β j f j ( X i , j ) + ∑ t = 1 T λ ( t ) D ( t ) + ɛ i ( t ) ( 1.3 )
similar to that used in the dummy variable model is estimated, with two significant modifications:
1. Only two time dummy variables, corresponding to the second and third time periods of the pair, are included. 2. The attribute values X j are transformed by continuous, piecewise linear functions ƒ j prior to finding the coefficients β j via multi-linear regression. The transformation functions ƒ j are found via a recursive inclusion procedure prior to the application of the final statistical regression.
Using a logarithmic hedonic function, the coefficients of the two time dummy variables then yield the one period logarithmic growth rates from period 1 to period 2 and from period 2 to period 3 in the subset.
The coefficients β j and transformations ƒ j are constant in the model over each “double adjacent period” ie. each triplet of periods. In reality, β j and ƒ j vary slowly over time, so that fitting a hedonic model over many periods simultaneously causes errors in the parameter estimates. The adjacent-period technique thus minimises the restriction on coefficient values and transformation functions.
The relationship between land size and sale price was found to be a power law ie. Log (sale price) is linear in log (land size).
The other input variables eg. number of bedrooms & number of bathrooms (in the case of residential property), whose relationship to the output logarithmic price is non-linear, are regressed singly as dummy variables against the log prices to obtain the input transformation functions discussed above.
The full hedonic input function is then assembled and regressed (distinctly for each triplet of periods) against the log prices to obtain the index growth rates. A mean squared error estimation method is used to determine the convexity adjustment in Point 3 above.
Input variables from the candidate list are retained in the final hedonic functional form if their coefficients β j are statistically significantly different from zero and of the correct sign.
The method is first applied to sales data in order to:
1. Calculate a capital gains index which allows the relative contributions of the attributes to vary with each time period, and 2. Impute values to each property in the population for which a sale was not observed during the period.
The method is next applied to rental data in order to obtain a rental imputation formula for all properties. This formula is then used to calculate cumulative rental income for each property and add it to the sales values, thus obtaining an “accumulation index”, similar in concept to the “accumulation index” on stock exchanges, which adds dividend payments stock prices charges.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Capital Gains Index
Given hedonic variables X 1 , . . . , X n , a double adjacent period hedonic formula, is used, applied to property sales P i in each triplet of periods (T k-2 ,T k−1 ,T k ):
log P i = c 0 ( T k ) + ∑ j = 1 m s j ( T k ) S j + ∑ j = 1 n c j ( T k ) f j ( x j ) + λ 1 ( T k ) τ 1 + λ 2 ( T k ) τ 2 + ɛ k ( 2.1 )
where:
The ƒ j are transformations of the hedonic variables. The c j are time varying numerical coefficients. The S j are dummy variables with S j =1 if property i is in suburb j. The s j are time varying numerical coefficients of the suburb dummy variables. τ 1 is a dummy variable with τ 1 =1 if the sale occurred in period T k−1 and τ 1 =0 otherwise. τ 2 is a dummy variable with τ 2 =1 if the sale occurred in period T k and τ 2 =0 otherwise. ε k is the (zero mean) residual error term
The above hedonic model thus gives the best estimate of the log return on a property, controlling for its most statistically significant, objectively observable price determining attributes.
The coefficients λ 1 ,λ 2 give the hedonic index log returns over the respective periods (T k-2 ,T k−1 ) and (T k−1 ,T k ). That is, if H(T) is the index value at time T, then
H ( T k−1 )=exp{λ 1 ( T k )+σ 1 ( T k ) 2 /2 }H ( T k-2 ) (2.2)
Ĥ ( T k )=exp{λ 2 ( T k )−λ 1 ( T k )+σ 2 ( T k ) 2 2 }H ( T k−1 ) (2.3)
where σ 1 (T k ),σ 2 (T k ) are respectively the standard error of λ 1 (T k ),λ 2 (T k ). These are adjustment terms to make the index track returns on a portfolio.
The value H(T k−1 ) is the final figure for the period (T k-2 ,T k−1 ) and Ĥ(T k ) is the indicative figure for the period (T k−1 ,T k ). Note that both these index numbers are actually calculated at the time T k+1 .
The hedonic index thus obtained is a capital gain index.
The average return on the hedonic property index over a period [t 0 ,t] is therefore an estimate of the average return on a diversified property portfolio over [t 0 ,t].
The transformations ƒ j are determined in the following manner:
Let input variable 1 be land size, with c 1 its coefficient and ƒ 1 its transformation.
The objective function
log P i = c 0 ( T k ) + ∑ j = 1 m s j ( T k ) S j + c 1 ( T k ) f 1 ( x 1 ) + λ 1 ( T k ) τ 1 + λ 2 ( T k ) τ 2 + ɛ k ( 2.4 )
is used to begin.
That is, landsize and suburb only are regressed against log of observed price.
Various functional forms of ƒ 1 have been tested, with the best ie. the one which minimises the standard deviation of the error ε k found to be ƒ 1 (x)=log x.
For each of the input variables i with a non-binary domain, let the range of observable values be x i,1 , . . . , x i,n i . For j=1, . . . , n i , let χ i,j be a dummy variable with χ i,j =1 if X i =x i,j .
For each i>1, determine the coefficients γ i,j in the regression:
log
P
i
=
c
0
(
T
k
)
+
∑
j
=
1
m
s
j
(
T
k
)
S
j
+
c
1
(
T
k
)
f
1
(
x
1
)
+
∑
j
=
1
n
i
γ
i
,
j
(
T
k
)
χ
i
,
j
+
λ
1
(
T
k
)
τ
1
+
λ
2
(
T
k
)
τ
2
+
ɛ
k
(
2.5
)
Each transformation function ƒ i , i>1 is then completely defined by ƒ i (x i,j )=γ i,j )=γ i,j .
Thus, each transformation ƒ i , i>1 is determined by regressing suburb and log (landsize) with dummy variables describing the possible values of the input X i against log of observed price, one input variable X i at a time.
Accumulation Index
Imputation of Rents
For a property which sells for a price P 1 at time T 1 , all imputed rental income for that property from a base period T 0 to the time T 1 is added to P 1 to obtain an accumulation price {tilde over (P)} 1 .
The accumulation prices are then regressed against time dummy variables and the same hedonic variables as in the capital gain hedonic index calculation (2.1) to obtain an accumulation index which estimates capital gain+gross rental yield.
Using (2.1) with suburb included, given hedonic variable values x 1 , . . . , x n for a property, the hedonic formula gives an estimate of any property price in any time period T k :
log
P
(
T
k
)
=
c
0
P
(
T
k
)
+
∑
j
=
1
n
c
j
P
(
T
k
)
f
j
(
x
j
)
+
ɛ
k
P
(
2.6
)
Similarly, a hedonic formula can be derived which uses the same transformations, but different coefficients to give an estimate of the rent for the period on any property in any time period T k :
log
R
(
T
k
)
=
c
0
R
(
T
k
)
+
∑
j
=
1
n
c
j
R
(
T
k
)
f
j
(
x
j
)
+
ɛ
k
R
(
2.7
)
Establish a base period T 0 .
For a property selling in period T k , we have the observed price P(T k ) which was used to calculate the hedonic estimate in (2.6) and, given the state vector (x 1 , . . . , x n ), the imputed rents {circumflex over (R)}(T 1 ), . . . , {circumflex over (R)}(T k ), obtained from (2.7):
R ^ ( T k ) = E [ R ( T k ) ❘ k ] = exp { c 0 R ( T k ) + ∑ j = 1 n c j R ( T k ) f j ( x j ) + ( σ k R ) 2 / 2 } ( 2.8 )
where σ k R is the standard deviation of the residual error ε k R .
The accumulation price is defined as follows:
P
~
(
T
k
)
=
P
(
T
k
)
+
∑
i
=
1
k
R
^
(
T
i
)
(
2.9
)
The same hedonic variables X 1 , . . . , X n are then regressed as in the capital gain index against the accumulation prices {tilde over (P)}(T k ), using the time dummy method in equations (2.1)-(2.3) to obtain a hedonic accumulation index which includes the imputed rents on a property by property basis.
Average Yield from Imputed Property Values
A fallback method to the accumulation price method for the hedonic accumulation index is required in situations where the errors in the estimation of the coefficients in the hedonic capital gains and accumulation indices are too large.
In such cases, an average rental yield is calculated from observed rents and imputed property values. Then this rental yield is added to the hedonic capital gains index return series to obtain the hedonic accumulation index return series and hence the hedonic accumulation index itself.
In a given period T k , we will receive rental data for a sample of N k properties. For each property in the sample, the hedonic state vector (X 1 , . . . , X n ) is used to input a price via equation (2.6):
P
^
(
T
k
)
=
E
[
P
(
T
k
)
❘
k
]
=
exp
{
c
0
P
(
T
k
)
+
∑
j
=
1
n
c
j
P
(
T
k
)
f
j
(
x
j
)
+
(
σ
k
P
)
2
/
2
}
(
2.10
)
The estimated mean rental yield for the period is calculated as follows:
y
(
T
k
)
=
∑
i
=
1
N
k
R
i
(
T
k
)
/
∑
i
=
1
N
k
P
^
i
(
T
k
)
(
2.11
)
If H(T) is the capital gain index, the accumulation index is calculated as
{tilde over (H)} ( T k+1 )= {tilde over (H)} ( T k )( H ( T k+1 )/ H ( T k )+ y ( T k+1 )) (2.12).
Method of Basing the Indices
An index has two purposes:
1. To accurately represent changes in value in the market between periods. 2. To accurately represent absolute market prices.
To achieve the first objective, the index must be able to be used to calculate the change in value of a representative market portfolio whose composition is held constant over a given time interval. This is the purpose of the hedonic formula (2.1).
To achieve the second objective, the index value must be set equal to an appropriate statistic of the distribution of values in the market eg. the median or mean.
These goals are conflicting because the first requires the representative portfolio to be held constant over the given period, whereas the second requires the representative portfolio to be regularly adjusted to match market composition. For example, if the percentage of 3 bedroom houses in the overall market increases, the percentage of 3 bedroom houses in the index calculation must correspondingly increase.
In order for a single property index series to achieve both the goals, it must be rebased at a regular set time intervals.
Specifically, suppose the index is calculated at times T 1 , T 2 , T 3 , . . . . Suppose rebasing occurs every k'th period ie. at T k , T 2k , T 3k , . . . .
For any given geographical region and dwelling type (eg houses/home units/outside Australia termed condominiums), we describe two methods for calculating the base index figures are described:
1. The base figure is calculated as the median of the distribution of the imputed prices in the given time period of all properties in the segment, measured in $000.
Explicitly, given a geographical region and dwelling type, the hedonic method applied to a single period T k :
log P ( T k ) = c 0 ( T k ) + ∑ j = 1 n c j ( T k ) f j ( x j ) + ɛ k ( 2.13 )
gives us an estimate of the value of any property with hedonic attributes x 1 , . . . , x n at time T k :
P ^ ( T k ) = E [ P ( T k ) ❘ k ] = exp { c 0 ( T k ) + ∑ j = 1 n c j ( T k ) f j ( x j ) + σ k 2 / 2 } ( 2.14 )
where σ k 2 is the variance of ε k .
The index value for the base period is then chosen as the median of the distribution of all imputed prices {circumflex over (P)}(T k ) in the period, obtained from (2.14).
2. An alternative method for calculating the base value figure is to:
a. Extract from the imputation formula in (2.13) the coefficient c sub of the suburb dummy variable for each observed sale. b. The suburbs may then be ranked according to increasing c sub value. c. The suburbs are grouped via their ranking into N strata each as nearly equal as possible populations. d. The median of observed sales in each stratum is calculated: m 1 , . . . , m N . e. The base figure is the geometric mean
m
1
…
m
N
N
.
Method 2 above is used in the event that either:
The coefficient estimates in (2.13) have excessively large confidence intervals, rendering the estimation of the distribution of values via (2.14) inaccurate. The distribution of hedonic attributes of the dwelling stock which existed during the basing period is unavailable. This is currently the case prior to the 1990's.
Derivatives
Six (6) classes of property derivative contracts are described whose cash flows depend directly on, and are calculated directly from, a hedonic (including hedonic based imputation) property index:
1. A forward or futures contract over a hedonic property index. 2. A property return swap whose income stream depends on the values of a hedonic property index. 3. A note whose capital value and income stream depends on the values of hedonic property indices. 4. A call or put option contract over a hedonic property index. 5. A cap, floor or collar over a hedonic property index. 6. An option to buy or sell at a later date a property return swap whose income stream depends on the values of a hedonic property index.
1. Forward Contracts
Forward and futures contracts will pay out the notional value of the contract times the difference between the level of the underlying hedonic price index as at the contract settlement date and the contract's strike index level. This payout mechanism can be written as
Payout( T )=Notional Principal*(Index( T )−Strike)
where T is the contract settlement date. The strike or delivery price is set when a contract is initiated. It is the expected value of the underlying index at the contract expiry date.
The notional value of a contract is effectively the dollar sensitivity of the trade to a one point change in the relevant index value; bullish (long) trades will have a positive notional amount; bearish (short) trades will have a negative notional amount.
A subcategory of forward contracts is contracts for difference (CFDs).
2. Property Return Swaps
Swaps in general involve two counterparties exchanging one set of cash flows for another. It is usual for the two sets of cash flows to be derived from two different assets or groups of assets.
The payer or seller in a property return swap agrees to pay to the counterparty (the receiver or buyer) the percentage index return ie. change in the index over the time period times a notional principal amount. The swap will usually be structured into multiple, equal time periods, with payments at the end of each.
In return, the receiver or buyer pays to the seller the percentage return on another asset (or possibly an agreed fixed rate) times the notional principal amount.
In practice, there is a netting agreement, so that physical payments are only one way in each period.
Suppose P is the notional principal, the contract commences at time t 0 and the payments are made at times t 1 , . . . , t n .
At time t k , the payer or seller pays an amount P(I(t k )/I(t k−1 )−1), where I(t) is the property index value.
At time t k , the receiver or buyer either:
Pays an amount P(A(t k )/A(t k−1 )−1), where A(t) is the buyer's reference asset value. Pays an amount P(ƒ(t k −t k−1 )), where ƒ is the agreed fixed rate per annum.
The property index used can be either a capital gain index, an accumulation index, or a combination of both eg. an average.
3. Property Index Notes
Index-linked notes are issued by major broker-dealers via a AA-rated (or higher) entity. The repayment of principal and interest are backed by the full faith and credit of the issuing firm.
The note pays a coupon (regular interest-like payment) which is derived from the then current values of the capital gains and accumulation indices, thus simulating a rental yield. The note is redeemable at expiry for the then current value of the capital gains index. The principle is that a note over a specific index synthesises returns on a diversified portfolio of property of the type and in the region covered by the index, by making payments which depend on the calculated values of the index.
For example, Brisbane house notes will pay a return derived from the values of the Brisbane house capital gains and accumulation indices.
Suppose the note makes payments which are returns on the underlying principal P, is the notional principal, the contract commences at time t 0 and the payments are made at times t 1 , . . . , t n , where t n is the expiry date of the note.
If the note originally sells for a price P, it is redeemable for P(C(t n )/C(t 0 )−ƒ(t n −t 0 )) or P(1−ƒ)C(t n )/C(t 0 ), where C(t) is the value of the capital gains index and ƒ is a fee to cover management costs of the issuer.
If A(t) is the value of the accumulation index, define the implied gross rental yield over the period [t k−1 ,t k ] as y k =A(t k )/A(t k−1 )−C(t k )/C(t k−1 ).
The property index note pays a coupon K(t k ) at t k equal to a multiple of the gross rental yield: K(t k )=kPy k , where k is a constant multiple.
4. Calls & Puts
A call option over a property index is the right to buy the index at the contractually defined strike or delivery price on or before the option contract expiry date.
Suppose P is the notional principal, the delivery price is K and the contract expires at time T.
For what is commonly known as a European option, the option can only be exercised at time T. For what is commonly known as an American option, the option can be exercised at any time up to and including T.
If t is the actual exercise time, the seller pays an amount P(I(t)−K) + , where I(t) is the property index value at time t and the value of (I−K) + is I−K if I>K and 0 otherwise.
A put option over a property index is the right to sell the index at the contractually defined strike or delivery price on or before the option contract expiry date.
If t is the actual exercise time, the seller pays an amount P(K−I(t)) + , where I(t) is the property index value at time t.
Call or put options are thus forward contracts where the holder or buyer is not legally required to settle: they can simply allow the contract to expire if settling would create an unfavourable outcome.
Because the underlying asset is the index, the contracts are purely synthetic. It is therefore not possible for the seller to settle the contract by providing the underlying asset. Thus, all property index call and put option contracts are settled in cash.
Variants to the standard payout of P(I(t)−K) + for calls and P(K−I(t)) + for puts:
Instead of the final index figure I(t) at the exercise date t, substitute an arbitrary function of the index over a set of times t 1 , . . . , t n ≦t. For example, a call option might pay out on the average value of the index: P((I(t 1 )+I(t 2 )+ . . . +I(t n ))/n−K) + . Instead of the fixed delivery price K, substitute an arbitrary function of the index over a set of times t 1 , . . . , t n ≦t. For example, the delivery price of a call might be the minimum value of the index over a set of times, so the payout is: P(I(t n )−min(I(t 1 ), I(t 2 ), . . . , I(t n ))).
5. Caps, Floors & Collars
A cap over a property index is a property return swap over that index, where the return in any given period payable by the seller is capped at an agreed maximum value.
Thus, if this agreed maximum period return is M, at each time t k , the payer or seller pays an amount P*min(I(t k )/I(t k )/I(t k−1 )−1,M), where I(t) is the property index value.
A floor over a property index is a property return swap over that index, where the return in any given period payable by the seller is guaranteed to be an agreed minimum value (often 0).
Thus, if this agreed maximum period return is m, at each time t k , the payer or seller pays an amount P*max(I(t k )/I(t k−1 )−1,m), where I(t) is the property index value.
A property collar is a property return swap with a cap and a floor: the payer pays returns on the index, at least an agreed minimum, but at most an agreed maximum.
Caps, floors and collars are settled in cash at the end of each payment period.
6. Swaptions
A call swaption is the option to be the buyer in a property return swap at an agreed price. That is, a call swaption with expiry date T and delivery price K entitles the holder to enter into a property return swap which commences upon exercise of the option at a time t≦T. If the holder exercises the swaption, they will receive property returns on the notional principal over the specified index for the specified period and in return pay the fixed return K on the notional principal.
A put swaption is the option to be the seller in a property return swap at an agreed price. That is, a put swaption with expiry date T and delivery price K entitles the holder to enter into a property return swap which commences upon exercise of the option at a time t≦T. If the holder exercises the swaption, they will pay property returns on the notional principal over the specified index for the specified period and in return receive the fixed return K on the notional principal. Variants are call and put swaptions over caps, floors and collars.
Example Housing Index
1. Data
For the purpose of this worked example, 56 observations of house sales are drawn from the Sydney suburbs of Balmain, Leichhardt, and Paddington over the period 1 Mar. 2007 to 30 Jun. 2007. This enables a demonstration of the index estimation process from one period to the next.
When broken into the two distinct triple-month time periods necessary for the index calculation in Equation 2.1, it can be seen that the first grouping—March, April, May—has 46 sales observations, whereas the second grouping—April, May, June—has 35. While roughly comparable, such variation is to be expected with the seasonality of the housing market. In this example, it would be reasonable to conclude that there are less sales in June than in March as the Sydney housing market moves into the slower winter months. This change in volumes, however, is also reflective of the timeliness issue associated with housing data, and supports the use of “Indicative” index figures, which are later adjusted to a “Final” value.
For each sales record, the sale price and date are recorded as well as detailed hedonic attribute data comprising the total property landsize, number of bedrooms, bathrooms and carspaces, and the presence of a scenic view, a pool, waterfrontage, and air-conditioning. In this example, these variables represent the X n hedonic variables in Equation 2.1. Details of this data are provided in Table 1. An observation ID has been assigned to each sales record in this example, to enable easy cross-referencing through each step.
2. Deriving Transformations
In order to estimate Equation 2.1, the necessary transformations of the hedonic variables, ƒ j , must first be derived. As discussed in the text, the optimal transformation for the land-size variable is found to be ƒ 1 (x)=log x. Transformations for the variables bedrooms, bathrooms, and carspaces, are obtained by estimating Equation 2.5. This regression requires log(Sale Price) as the dependent variable, the transformed land-size variable, log(land-size), dummy variables for the suburb location and dummy variables for the range of possible values of the respective hedonic Xi variables. The layout of this data is presented in Table 2.
In this example, the ranges of the non-binary hedonic variables is: Bedrooms [2,3,4]; Bathrooms[1,2,3]; and, Carspaces[0,1,2]. In order to avoid the “dummy variable trap,” the coefficient of one value of each variable is restricted to zero. In this example, it is Bedrooms=3; Bathrooms=2; and, Carspaces=1. Similarly, the coefficient of the Balmain suburb is restricted to zero. The choice as to which value to restrict does not affect the outcome: the estimated coefficients on the other values comes to represent its value relative to the restricted variable.
3. Transformations
The results of estimating Equation 2.5 on the data presented in Table 2 are presented in Tables 3A, 3B, and 3 C.
The R 2 of all these regressions are reasonably high (lowest=0.73; highest=0.85), reflecting the ability of land-size and location to explain a high proportion of variability in prices. The estimated coefficients have the expected signs, and for the most part are estimated with a high degree of statistical significance. Given these results are derived for a small random sample of the total population of sales, it is likely that the fit and significance of the model is in fact much stronger than presented here.
Taking the averages in the estimated coefficients for each possible value of input Xi over the two triplet-month periods, yields the transformations summarized in Table 3D below. These results support a priori expectations that: (a) there is value in every additional bedrooms, bathrooms, or carspace; and (b) the incremental value of each additional attribute is not linear. This result supports the use of transformations when analysing this data.
4. Transformed Data
Having obtained the transformations for all non-binary variables—in this example, bedrooms, bathrooms, and carspaces—the observed hedonic attribute values are replaced by their transformations. For example, sales observation 1 had three bedrooms; the transformed bedrooms variable for observation 1 is now 0. Similarly, sale price and land-size have been substituted with their respective logs. The binary attribute variables—waterfrontage, view, pool, air-conditioning—as well as suburb have been replaced with dummy variables equal to 1 in the presence of the variable (or locality, in the case of suburbs), and 0 otherwise. The suburb Balmain is not included, as in the transformation regressions (section 2), to ensure full-rank in the regression matrix.
The layout of the data given this transformation is presented in Table 4. This is now the final data format for fitting Equation 2.1: the hedonic index estimation.
5. Hedonic Regression
The results from fitting Equation 2.1 to the transformed data presented in the previous section for each of the triple-month periods are set out in Table 5. Again, the models show a high degree of fit by the R 2 statistic, and generally the coefficient estimates have the expected sign and magnitude. Since these numbers are drawn from a small sample, however, little weight should be applied to their meaning; these numbers are designed to illustrate the index process.
The results of interest are the estimated on the time dummy variables: the λ ji . These represent the estimated monthly index growth rate. The next section outlines how these numbers are adjusted to correct from bias arising from the logarithmic transformation of the function, with the final section demonstrating how an index is then formed from these estimates via a chain-linking process.
6. Bias Correction
To make the index track the returns on a portfolio, the lamda estimates must be adjusted for bias induced by the logarithmic transformation of the regression function. The formula for this correction is set out inside the brackets in Equations 2.2 and 2.3. The results from the regression of Equation 2.1 and the subsequent corrected lamda results are presented in Table 6 below.
7. Index Calculation
This final section demonstrates the chain-linking process by which the bias-corrected lamda estimates form the hedonic house price index.
A base value is required. For the purpose of this example, the actual value of the RP Data-Rismark Sydney House Price Index as at March-2007, 548.289 is used. For the first triple-month period, T=1, Equation 2.2 gives the April 2007 value, and Equation 2.3 gives the May-2007 value. Similarly, for the second triple-month time period, Equations 2.2 and 2.3 yield the index results as at May-2007 and June-2007, respectively. For the purpose of the trading index, the latest month in each tri-month period is “Indicative.” Each subsequent month, the previous “Indicative” estimate is revised to a final, or “Fixed,” value. The estimated index is presented below in Table 7, and charted in FIG. 4 . The plotted index shows the movement in aggregate property prices as well as the updating of indicative index value to fixed values.
The methods and processes described above are preferably practised using a conventional general-purpose computer system 60 , such as that shown FIG. 5 wherein the processes are implemented as software, such as an application program executed within the computer system 60 . In particular, the steps of the processes are effected by instructions in the software that are carried out by the computer. The software can be divided into two separate parts; one part for carrying out the specific processes; and another part to manage the user interface between the latter and the user. The software is able to be stored in a computer readable medium, including the storage devices described below, for example. The software is loaded into the computer from the computer readable medium, and then executed by the computer. A computer readable medium having such software or computer program recorded on it is a computer program product. The use of the computer program product in the computer results in an advantageous apparatus for carrying out embodiments of the invention.
The computer system 60 comprises a computer module 61 , input devices such as a keyboard 62 and mouse 63 , output devices including a printer 65 and a display device 64 . A Modulator-Demodulator (Modem) transceiver 76 is used by the computer module 61 for communicating to and from a communications network 80 , for example connectable via a telephone line 81 or other functional medium. The modem 76 can be used to obtain access to the Internet, and other network systems, such as a Local Area Network (LAN) or a Wide Area Network (WAN) or other computers 160 , 260 , . . . 960 , etc each with their own corresponding modem 176 , 276 , . . . 976 , etc and each having a data input terminal 162 , 262 , . . . 962 , etc. Each of the computers 160 - 960 are used to collect data for the preparation of an index, for example.
The computer module 61 typically includes at least one processor unit 65 , a memory unit 66 , for example formed from semiconductor random access memory (RAM) and read only memory (ROM). There are input/output (I/O) interfaces including a video interface 67 , and an I/O interface 73 for the keyboard 62 , mouse 63 and optionally a card reader 59 , and a further interface 68 for the printer 65 or optionally a camera 77 . A storage device 69 is provided and typically includes a hard disk drive 70 and a floppy disk drive 71 . A magnetic tape drive (not illustrated) can also be used. A CD-ROM drive 72 is typically provided as a non-volatile source of data. The components 65 to 73 of the computer module 61 , typically communicate via an interconnected bus 64 and in a manner which results in a conventional mode of operation of the computer system 60 known to those in the relevant art. Examples of computers on which the embodiments can be practiced include IBM-PC's and compatibles, Sun Sparcstations or alike computer systems evolved therefrom.
Typically, the application program of the preferred embodiment is resident on the hard disk drive 70 and read and controlled in its execution by the processor 65 . Intermediate storage of the program and any data from the network 80 is accomplished using the semiconductor memory 66 , possibly in concert with the hard disk drive 70 . In some instances, the application program is encoded on a CD-ROM or floppy disk and read via the corresponding drive 72 or 71 , or alternatively is read from the network 80 via the modem device 76 . Still further, the software can also be loaded into the computer system 60 from other computer readable media including magnetic tape, a ROM or integrated circuit, a magneto-optical disk, a radio or infra-red transmission channel between the computer module 61 and another device, a computer readable card such as a PCMCIA card, and the Internet and Intranets including email transmissions and information recorded on websites and the like. The foregoing is merely exemplary of relevant computer readable media. Other computer readable media may be practiced without departing from the scope and spirit of the invention.
It should not be lost sight of that the purpose of the computer system 60 is to generate a digitally encoded electric signal (such as that illustrated in FIG. 6 ) which when applied to an output interface (such as the display device 64 or the printer 65 ) produces an indicium or indicia which convey information and which are legible or intelligible to a human. For example, the electric signal illustrated in FIG. 6 is a binary encoded signal 01001 which when applied to the display device 64 or printer 65 causes the indicium 9 to be displayed or printed.
The processes can alternatively be implemented in dedicated hardware such as one or more integrated circuits performing the functions or sub functions of the processes. Such dedicated hardware can include graphic processors, digital signal processors, or one or more microprocessors and associated memories.
The foregoing describes only some embodiments of the present invention and modifications, obvious to those skilled in the financial and computing arts, can be made thereto without departing from the scope of the present invention.
The term “comprising” (and its grammatical variations) as used herein is used in the inclusive sense of “including” or “having” and not in the exclusive sense of “consisting only of”.
TABLE 1
Data
This table provides details of the sales observations used in the worked example. There are 56 house sales used with the following
sales and attribute detail: sale price and date, suburb, and total property landsize; the number of bedrooms, bathrooms and
carspaces; and the presence of a scenic view, a pool, waterfrontage, and air-conditioning.
Observation
Landsize
Scenic
ID
Sale Price
Sale Date
(ha)
Bedrooms
Bathrooms
Carspaces
View
Pool
Waterfront
Air-Con
Suburb
1
1,105,000
Mar. 1, 2007
0.0196
3
2
0
No
No
No
No
BALMAIN
2
705,000
Mar. 2, 2007
0.0181
2
1
0
No
No
No
No
BALMAIN
3
708,000
Mar. 3, 2007
0.0143
3
1
0
No
No
No
No
LEICHHARDT
4
725,000
Mar. 3, 2007
0.0205
2
1
0
No
No
No
No
LEICHHARDT
5
863,000
Mar. 6, 2007
0.0186
4
1
0
No
No
No
No
LEICHHARDT
6
765,000
Mar. 7, 2007
0.0149
2
1
0
No
No
No
No
BALMAIN
7
1,060,000
Mar. 7, 2007
0.0181
3
1
1
No
No
No
No
PADDINGTON
8
873,000
Mar. 13,
0.0131
2
1
0
No
No
No
No
BALMAIN
2007
9
860,000
Mar. 13,
0.0197
3
2
2
No
No
No
No
LEICHHARDT
2007
10
1,100,000
Mar. 14,
0.0133
4
1
0
No
No
No
No
PADDINGTON
2007
11
716,000
Mar. 17,
0.0125
2
1
1
No
No
No
No
LEICHHARDT
2007
12
952,000
Mar. 21,
0.0162
3
1
0
No
No
No
No
BALMAIN
2007
13
1,125,000
Mar. 21,
0.0228
3
2
2
No
No
Yes
No
BALMAIN
2007
14
705,000
Mar. 21,
0.0211
2
1
0
No
No
No
No
LEICHHARDT
2007
15
997,500
Mar. 24,
0.0138
2
1
0
No
No
No
No
PADDINGTON
2007
16
840,000
Mar. 30,
0.0185
2
1
1
No
No
Yes
No
BALMAIN
2007
17
970,000
Mar. 30,
0.0142
3
1
0
No
No
No
No
BALMAIN
2007
18
820,000
Mar. 31,
0.0204
3
2
2
No
No
No
No
LEICHHARDT
2007
19
1,050,000
Mar. 31,
0.0126
3
3
0
Yes
No
No
No
PADDINGTON
2007
20
1,020,000
Mar. 31,
0.0127
3
2
0
No
No
No
No
PADDINGTON
2007
21
1,011,000
Mar. 31,
0.015
3
2
1
No
No
No
No
PADDINGTON
2007
22
870,000
Apr. 3,
0.0228
3
1
0
No
No
No
No
BALMAIN
2007
23
900,000
Apr. 3,
0.0139
2
2
1
No
No
No
Yes
PADDINGTON
2007
24
920,000
Apr. 11,
0.0182
3
2
0
No
No
No
No
PADDINGTON
2007
25
935,000
Apr. 12,
0.0157
3
2
0
No
No
No
No
BALMAIN
2007
26
700,000
Apr. 14,
0.0171
2
1
0
No
No
No
Yes
LEICHHARDT
2007
27
874,000
Apr. 14,
0.0144
2
1
0
No
No
No
No
PADDINGTON
2007
28
836,000
Apr. 19,
0.0183
2
1
0
Yes
No
No
No
BALMAIN
2007
29
1,145,000
Apr. 19,
0.0186
4
2
1
No
Yes
No
No
PADDINGTON
2007
30
1,164,000
Apr. 19,
0.018
4
2
1
No
Yes
No
No
PADDINGTON
2007
31
952,000
Apr. 20,
0.014
3
2
1
No
No
No
Yes
BALMAIN
2007
32
710,000
Apr. 21,
0.0182
3
1
0
No
No
No
No
BALMAIN
2007
33
870,000
Apr. 27,
0.0127
3
2
0
No
No
No
No
BALMAIN
2007
34
690,000
Apr. 28,
0.0145
2
1
0
No
No
No
No
LEICHHARDT
2007
35
700,000
Apr. 28,
0.0134
3
1
1
No
No
No
No
LEICHHARDT
2007
36
703,000
May 3,
0.0177
2
1
1
No
No
No
No
LEICHHARDT
2007
37
825,000
May 5,
0.013
4
3
1
No
No
No
Yes
LEICHHARDT
2007
38
705,000
May 8,
0.0186
3
1
1
No
No
No
No
LEICHHARDT
2007
39
1,050,000
May 11,
0.0177
3
2
0
No
No
No
No
PADDINGTON
2007
40
820,000
May 12,
0.0127
3
2
0
No
No
No
No
BALMAIN
2007
41
727,000
May 12,
0.0152
2
1
0
No
No
No
No
BALMAIN
2007
42
715,000
May 16,
0.0156
2
2
0
No
No
No
No
BALMAIN
2007
43
895,000
May 24,
0.0155
2
1
1
No
No
Yes
No
BALMAIN
2007
44
796,000
May 26,
0.0158
3
1
1
No
No
No
No
LEICHHARDT
2007
45
840,000
May 28,
0.0228
3
1
1
No
No
No
No
BALMAIN
2007
46
920,000
May 30,
0.0211
4
2
0
No
No
No
No
BALMAIN
2007
47
800,000
Jun. 1,
0.0227
3
1
0
No
No
No
No
BALMAIN
2007
48
825,000
Jun. 2,
0.0169
2
1
0
No
No
No
No
BALMAIN
2007
49
853,000
Jun. 5,
0.0184
4
2
0
No
No
No
No
BALMAIN
2007
50
877,500
Jun. 6,
0.0133
3
1
0
No
No
No
No
BALMAIN
2007
51
690,000
Jun. 6,
0.0196
3
1
2
No
No
No
No
LEICHHARDT
2007
52
677,500
Jun. 20,
0.0186
2
1
1
No
No
No
No
LEICHHARDT
2007
53
955,000
Jun. 27,
0.0146
4
2
0
Yes
No
No
No
LEICHHARDT
2007
54
1,085,000
Jun. 29,
0.0199
3
2
0
No
No
No
No
BALMAIN
2007
55
710,000
Jun. 29,
0.0191
2
1
0
No
No
No
No
LEICHHARDT
2007
56
717,717
Jun. 30,
0.0183
2
1
0
No
No
No
Yes
LEICHHARDT
2007
TABLE 2
Data for deriving transformations
This table sets out the manipulated data used to estimate the transformations which
will be used in the house price index estimation. The 56 sales observations are those
presented in Table 1, but with the necessary dummy variables substituted for the non binary
hedonic attributes and suburb, and the logarithmic transformation of landsize and sale price.
From this format, regression equation 2.5 is estimated.
Obs
Sale
Landsize
In[Sale
In[Land-
ID
Price
Sale Date
(ha)
Price]
size]
D[Beds = 2]
D[Beds = 4]
1
1,105000
Mar. 1,
0.0196
13.915
−3.9322
0
0
2007
2
705,000
Mar. 2,
0.0181
13.466
−4.0118
1
0
2007
3
708,000
Mar. 3,
0.0143
13.470
−4.2475
0
0
2007
4
725,000
Mar. 3,
0.0205
13.494
−3.8873
1
0
2007
5
863,000
Mar. 6,
0.0186
13.668
−3.9846
0
1
2007
6
765,000
Mar. 7,
0.0149
13.548
−4.2064
1
0
2007
7
1,060,000
Mar. 7,
0.0181
13.874
−4.0118
0
0
2007
8
873,000
Mar. 13,
0.0131
13.68
−4.3351
1
0
2007
9
860,000
Mar. 13,
0.0197
13.665
−3.9271
0
0
2007
10
1,100,000
Mar. 14,
0.0133
13.911
−4.32
0
1
2007
11
716,000
Mar. 17,
0.0125
13.481
−4.382
1
0
2007
12
952,000
Mar. 21,
0.0162
13.766
−4.1227
0
0
2007
13
1,125,000
Mar. 21,
0.0228
13.933
−3.781
0
0
2007
14
705,000
Mar. 21,
0.0211
13.466
−3.8585
1
0
2007
15
997,500
Mar. 24,
0.0138
13.813
−4.2831
1
0
2007
16
840,000
Mar. 30,
0.0185
13.641
−3.99
1
0
2007
17
970,000
Mar. 30,
0.0142
13.785
−4.2545
0
0
2007
18
820,000
Mar. 31,
0.0204
13.617
−3.8922
0
0
2007
19
1,050,000
Mar. 31,
0.0126
13.864
−4.3741
0
0
2007
20
1,020,000
Mar. 31,
0.0127
13.835
−4.3662
0
0
2007
21
1,011,000
Mar. 31,
0.015
13.826
−4.1997
0
0
2007
22
870,000
Apr. 3,
0.0228
13.676
−3.781
0
0
2007
23
900,000
Apr. 3,
0.0139
13.71
−4.2759
1
0
2007
24
920,000
Apr. 11,
0.0182
13.732
−4.0063
0
0
2007
25
935,000
Apr. 12,
0.0157
13.748
−4.1541
0
0
2007
26
700,000
Apr. 14,
0.0171
13.459
−4.0687
1
0
2007
27
874,000
Apr. 14,
0.0144
13.681
−4.2405
1
0
2007
28
836,000
Apr. 19,
0.0183
13.636
−4.0009
1
0
2007
29
1,145,000
Apr. 19,
0.0186
13.951
−3.9846
0
1
2007
30
1,164,000
Apr. 19,
0.018
13.967
−4.0174
0
1
2007
31
952,000
Apr. 20,
0.014
13.766
−4.2687
0
0
2007
32
710,000
Apr. 21,
0.0182
13.473
−4.0063
0
0
2007
33
870,000
Apr. 27,
0.0127
13.676
−4.3662
0
0
2007
34
690,000
Apr. 28,
0.0145
13.444
−4.2336
1
0
2007
35
700,000
Apr. 28,
0.0134
13.459
−4.3125
0
0
2007
36
703,000
May 3,
0.0177
13.463
−4.0342
1
0
2007
37
825,000
May 5,
0.013
13.623
−4.3428
0
1
2007
38
705,000
May 8,
0.0186
13.466
−3.9846
0
0
2007
39
1,050,000
May 11,
0.0177
13.864
−4.0342
0
0
2007
40
820,000
May 12,
0.0127
13.617
−4.3662
0
0
2007
41
727,000
May 12,
0.0152
13.497
−4.1865
1
0
2007
42
715,000
May 16,
0.0156
13.48
−4.1605
1
0
2007
43
895,000
May 24,
0.0155
13.705
−4.1669
1
0
2007
44
796,000
May 26,
0.0158
13.587
−4.1477
0
0
2007
45
840,000
May 28,
0.0228
13.641
−3.781
0
0
2007
46
920,000
May 30,
0.0211
13.732
−3.8585
0
1
2007
47
800,000
May 1,
0.0227
13.592
−3.7854
0
0
2007
48
825,000
Jun. 2,
0.0169
13.623
−4.0804
1
0
2007
49
853,000
Jun. 5,
0.0184
13.657
−3.9954
0
1
2007
50
877,500
Jun. 6,
0.0133
13.685
−4.32
0
0
2007
51
690,000
Jun. 6,
0.0196
13.444
−3.9322
0
0
2007
52
677,500
Jun. 20,
0.0186
13.426
−3.9846
1
0
2007
53
955,000
Jun. 27,
0.0146
13.769
−4.2267
0
1
2007
54
1,085,000
Jun. 29,
0.0199
13.897
−3.917
0
0
2007
55
710,000
Jun. 29,
0.0191
13.473
−3.958
1
0
2007
56
717,717
Jun. 30,
0.0183
13.484
−4.0009
1
0
2007
Obs
D[Suburb =
D[Suburb =
ID
D[Baths = 1]
D[Baths = 3]
D[Cars = 0]
D[Cars = 2]
Leichhardt]
Paddington]
1
0
0
0
0
0
0
2
1
0
1
0
0
0
3
1
0
1
0
1
0
4
1
0
1
0
1
0
5
0
1
0
1
1
0
6
1
0
1
0
0
0
7
1
0
0
0
0
1
8
1
0
1
0
0
0
9
0
0
0
1
1
0
10
1
0
0
1
0
1
11
1
0
0
0
1
0
12
1
0
0
0
0
0
13
0
0
0
1
0
0
14
1
0
1
0
1
0
15
1
0
1
0
0
1
16
1
0
0
0
0
0
17
1
0
1
0
0
0
18
0
0
0
1
1
0
19
0
1
1
0
0
1
20
0
0
1
0
0
1
21
0
0
0
0
0
1
22
1
0
1
0
0
0
23
0
0
0
0
0
1
24
0
0
1
0
0
1
25
0
0
0
0
0
0
26
1
0
1
0
1
0
27
1
0
1
0
0
1
28
1
0
1
0
0
0
29
0
0
0
0
0
1
30
0
1
0
1
0
1
31
0
0
0
0
0
0
32
1
0
1
0
0
0
33
0
0
0
1
0
0
34
1
0
1
0
1
0
35
1
0
0
0
1
0
36
1
0
0
0
1
0
37
0
1
0
0
1
0
38
1
0
0
0
1
0
39
0
0
1
0
0
1
40
0
0
1
0
0
0
41
1
0
1
0
0
0
42
0
0
1
0
0
0
43
1
0
0
0
0
0
44
1
0
0
0
1
0
45
1
0
0
0
0
0
46
0
1
1
0
0
0
47
1
0
1
0
0
0
48
1
0
1
0
0
0
49
0
0
1
0
0
0
50
1
0
1
0
0
0
51
1
0
0
1
1
0
52
1
0
0
0
1
0
53
0
0
1
0
1
0
54
0
0
1
0
0
0
55
1
0
1
0
1
0
56
1
0
1
0
1
0
TABLE 3A
Bedrooms
Tri-period 1: March-April-May
Tri-period 2: April-May-June
Panel A: Regression Statistics
Multiple R
0.8525
0.8445
R Square
0.7267
0.7132
Adjusted R Square
0.6925
0.6638
Standard Error
0.0884
0.0876
Observations
46
35
Panel B: Coefficient Estimates
Standard
Standard
Coefficients
Error
t Stat
P-value
Coefficients
Error
t Stat
P-value
Intercept
14.0107
0.3091
45.3201
5.3E−36
13.5309
0.3657
37.0022
5.8E−26
Insize
0.0737
0.0757
0.9736
0.3361
−0.0321
0.0898
−0.3576
0.7232
Bed2
−0.1104
0.0286
−3.8532
0.0004
−0.0771
0.0337
−2.2861
0.0297
Bed4
0.0775
0.0417
1.8609
0.0701
0.1199
0.0432
2.7762
0.0095
sub2
−0.1468
0.0311
−4.7187
2.9E−05
−0.1359
0.0341
−3.9885
0.0004
sub3
0.1412
0.0342
4.1232
0.0002
0.141
0.0428
3.2919
0.0026
TABLE 3B
Bathrooms
Tri-period 1: March-April-May
Tri-period 2: April-May-June
Panel A: Regression Statistics
Multiple R
0.8133
0.8226
R Square
0.6614
0.6767
Adjusted R Square
0.6191
0.6209
Standard Error
0.0984
0.0931
Observations
46
35
Panel B: Coefficient Estimates
Standard
Standard
Coefficients
Error
t Stat
P-value
Coefficients
Error
t Stat
P-value
Intercept
14.2079
0.3409
41.6805
1.41E−34
14.1042
0.4174
33.7878
7.67E−25
Insize
0.1199
0.0833
1.4389
0.158
0.0952
0.1004
0.9482
0.3509
Bath1
−0.086
0.0335
−2.5669
0.0141
−0.1261
0.0406
−3.106
0.0042
Bath3
0.052
0.0517
1.0053
0.3208
0.0544
0.0615
0.8845
0.3837
sub2
−0.1374
0.0351
−3.9193
0.0003
−0.1048
0.0379
−2.7644
0.0098
sub3
0.1484
0.0378
3.9295
0.0003
0.1151
0.0461
2.4962
0.0189
TABLE 3C
Carspaces
Tri-period 1: March-April-May
Tri-period 2: April-May-June
Panel A: Regression Statistics
Multiple R
0.8496
0.7311
R Square
0.7218
0.5345
Adjusted R Square
0.687
0.4543
Standard Error
0.0892
0.1117
Observations
46
35
Panel B: Coefficient Estimates
Standard
Standard
Coefficients
Error
t Stat
P-value
Coefficients
Error
t Stat
P-value
Intercept
14.0385
0.3151
44.5503
1.04E−35
13.7617
0.4753
28.9516
5.97E−23
Insize
0.0808
0.0767
1.0538
0.2983
0.0194
0.1152
0.1686
0.8672
Cars0
−0.0877
0.029
−3.0201
0.0044
−0.043
0.0428
−1.0065
0.3225
Cars2
0.091
0.0408
2.2325
0.0312
0.015
0.0727
0.2061
0.8382
sub2
−0.17
0.0316
−5.3738
3.57E−06
−0.157
0.0437
−3.59
0.0012
sub3
0.1634
0.0335
4.8808
1.73E−05
0.1545
0.0539
2.8679
0.0076
TABLE 3D
Estimated Transformations
Attribute
Observed
Transformation
Bedrooms
2
−0.0937
Bedrooms
3
0
Bedrooms
4
0.0987
Bathrooms
1
−0.1061
Bathrooms
2
0
Bathrooms
3
0.0532
Carspaces
0
−0.0654
Carspaces
1
0
Carspaces
2
0.053
TABLE 4
Transformed Data
This table contains the transformed data in the format necessary for the final index
estimation as set out in Equation 2.1. The dependant sale price variable has been
transformed, log[Sale Price], as have the non-binary hedonic variables, where
landsize has been replaced by its logarithmic transformation, and bedrooms,
bathrooms, and carspaces observations have been substituted with their respective
transformed value as set out in Table 3D. Binary variables, including suburb, have been
replaced with dummy variables, and the month of sale has been replaced with a dummy
variable as well.
In[Sale
In[Land-
ID
Price]
size]
T[Bedrms]
T[Bathrms]
T[Cars]
D[Water]
D[View]
D[Pool]
1
13.9154
−3.9322
0.0000
0
−0.0654
0
0
0
2
13.4660
−4.0118
−0.0937
−0.1061
−0.0654
0
0
0
3
13.4702
−4.2475
0.0000
−0.1061
−0.0654
0
0
0
4
13.4939
−3.8873
−0.0937
−0.1061
−0.0654
0
0
0
5
13.6682
−3.9846
0.0987
−0.1061
−0.0654
0
0
0
6
13.5476
−4.2064
−0.0937
−0.1061
−0.0654
0
0
0
7
13.8738
−4.0118
0.0000
−0.1061
0
0
0
0
8
13.6797
−4.3351
−0.0937
−0.1061
−0.0654
0
0
0
9
13.6647
−3.9271
0.0000
0
0.0530
0
0
0
10
13.9108
−4.3200
0.0987
−0.1061
−0.0654
0
0
0
11
13.4814
−4.3820
−0.0937
−0.1061
0
0
0
0
12
13.7663
−4.1227
0.0000
−0.1061
−0.0654
0
0
0
13
13.9333
−3.7810
0.0000
0
0.0530
1
0
0
14
13.4660
−3.8585
−0.0937
−0.1061
−0.0654
0
0
0
15
13.8130
−4.2831
−0.0937
−0.1061
−0.0654
0
0
0
16
13.6412
−3.9900
−0.0937
−0.1061
0
1
0
0
17
13.7851
−4.2545
0.0000
−0.1061
−0.0654
0
0
0
18
13.6171
−3.8922
0.0000
0
0.0530
0
0
0
19
13.8643
−4.3741
0.0000
0.0532
−0.0654
0
1
0
20
13.8353
−4.3662
0.0000
0
−0.0654
0
0
0
21
13.8265
−4.1997
0.0000
0
0
0
0
0
22
13.6762
−3.7810
0.0000
−0.1061
−0.0654
0
0
0
23
13.7102
−4.2759
−0.0937
0
0
0
0
0
24
13.7321
−4.0063
0.0000
0
−0.0654
0
0
0
25
13.7483
−4.1541
0.0000
0
−0.0654
0
0
0
26
13.4588
−4.0687
−0.0937
−0.1061
−0.0654
0
0
0
27
13.6808
−4.2405
−0.0937
−0.1061
−0.0654
0
0
0
28
13.6364
−4.0009
−0.0937
−0.1061
−0.0654
0
1
0
29
13.9509
−3.9846
0.0987
0
0
0
0
1
30
13.9674
−4.0174
0.0987
0
0
0
0
1
31
13.7663
−4.2687
0.0000
0
0
0
0
0
32
13.4730
−4.0063
0.0000
−0.1061
−0.0654
0
0
0
33
13.6762
−4.3662
0.0000
0
−0.0654
0
0
0
34
13.4444
−4.2336
−0.0937
−0.1061
−0.0654
0
0
0
35
13.4588
−4.3125
0.0000
−0.1061
0
0
0
0
36
13.4631
−4.0342
−0.0937
−0.1061
0
0
0
0
37
13.6231
−4.3428
0.0987
0.0532
0
0
0
0
38
13.4660
−3.9846
0.0000
−0.1061
0
0
0
0
39
13.8643
−4.0342
0.0000
0
−0.0654
0
0
0
40
13.6171
−4.3662
0.0000
0
−0.0654
0
0
0
41
13.4967
−4.1865
−0.0937
−0.1061
−0.0654
0
0
0
42
13.4800
−4.1605
−0.0937
0
−0.0654
0
0
0
43
13.7046
−4.1669
−0.0937
−0.1061
0
1
0
0
44
13.5874
−4.1477
0.0000
−0.1061
0
0
0
0
45
13.6412
−3.7810
0.0000
−0.1061
0
0
0
0
46
13.7321
−3.8585
0.0987
0
−0.0654
0
0
0
47
13.5924
−3.7854
0.0000
−0.1061
−0.0654
0
0
0
46
13.6231
−4.0804
−0.0937
−0.1061
−0.0654
0
0
0
49
13.6565
−3.9954
0.0987
0
−0.0654
0
0
0
50
13.6848
−4.3200
0.0000
−0.1061
−0.0654
0
0
0
51
13.4444
−3.9322
0.0000
−0.1061
0.0530
0
0
0
52
13.4262
−3.9846
−0.0937
−0.1061
0
0
0
0
53
13.7695
−4.2267
0.0987
0
−0.0654
0
1
0
54
13.8971
−3.9170
0.0000
0
−0.0654
0
0
0
55
13.4730
−3.9581
−0.0937
−0.1061
−0.0654
0
0
0
56
13.4838
−4.0009
−0.0937
−0.1061
−0.0654
0
0
0
D[Air-
D[Suburb =
D[Suburb =
T 1
T 2
T 1
T 2
ID
Con]
Leichhardt]
Paddington]
(T = 1)
(T = 1)
(T = 2)
(T = 2)
1
0
0
0
0
0
0
0
2
0
0
0
0
0
0
0
3
0
1
0
0
0
0
0
4
0
1
0
0
0
0
0
5
0
1
0
0
0
0
0
6
0
0
0
0
0
0
0
7
0
0
1
0
0
0
0
8
0
0
0
0
0
0
0
9
0
1
0
0
0
0
0
10
0
0
1
0
0
0
0
11
0
1
0
0
0
0
0
12
0
0
0
0
0
0
0
13
0
0
0
0
0
0
0
14
0
1
0
0
0
0
0
15
0
0
1
0
0
0
0
16
0
0
0
0
0
0
0
17
0
0
0
0
0
0
0
18
0
1
0
0
0
0
0
19
0
0
1
0
0
0
0
20
0
0
1
0
0
0
0
21
0
0
1
0
0
0
0
22
0
0
0
1
0
0
0
23
1
0
1
1
0
0
0
24
0
0
1
1
0
0
0
25
0
0
0
1
0
0
0
26
1
1
0
1
0
0
0
27
0
0
1
1
0
0
0
28
0
0
0
1
0
0
0
29
0
0
1
1
0
0
0
30
0
0
1
1
0
0
0
31
1
0
0
1
0
0
0
32
0
0
0
1
0
0
0
33
0
0
0
1
0
0
0
34
0
1
0
1
0
0
0
35
0
1
0
1
0
0
0
36
0
1
0
0
1
1
0
37
1
1
0
0
1
1
0
38
0
1
0
0
1
1
0
39
0
0
1
0
1
1
0
40
0
0
0
0
1
1
0
41
0
0
0
0
1
1
0
42
0
0
0
0
1
1
0
43
0
0
0
0
1
1
0
44
0
1
0
0
1
1
0
45
0
0
0
0
1
1
0
46
0
0
0
0
1
1
0
47
0
0
0
0
0
0
1
46
0
0
0
0
0
0
1
49
0
0
0
0
0
0
1
50
0
0
0
0
0
0
1
51
0
1
0
0
0
0
1
52
0
1
0
0
0
0
1
53
0
1
0
0
0
0
1
54
0
0
0
0
0
0
1
55
0
1
0
0
0
0
1
56
1
1
0
0
0
0
1
TABLE 5
Hedonic Index Regression
Tri-period 1: March-April-May
Tri-period 2: April-May-June
Panel A: Regression Statistics
Multiple R
0.9131
0.9014
R Square
0.8338
0.8125
Adjusted R Square
0.7734
0.7103
Standard Error
0.0759
0.0814
Observations
46
35
Panel B: Coefficient Estimates
Coefficient
Standard
Coefficient
Standard
Estimate
Error
t Stat
P-value
Estimate
Error
t Stat
P-value
Intercept
13.9394
0.2879
48.4135
3.12E−32
13.7968
0.4208
32.7841
3.59E−20
Ln[Land-size]
0.0427
0.0705
0.6059
0.5488
0.0317
0.0992
0.3194
0.7525
T[Bedrooms]
0.9688
0.2208
4.3872
0.0001
0.6176
0.3176
1.9445
0.0647
T[Bathrooms]
0.3073
0.2626
1.1704
0.2502
0.6498
0.4331
1.5002
0.1478
T[Carspaces]
0.3418
0.3990
0.8566
0.3979
−0.1084
0.5218
−0.2077
0.8374
D[Water]
0.0945
0.0576
1.6399
0.1105
0.1723
0.0950
1.8138
0.0834
D[View]
0.0418
0.0581
0.7197
0.4768
0.1025
0.0633
1.6178
0.1199
D[Pool]
0.0473
0.0709
0.6677
0.5090
0.1108
0.0849
1.3054
0.2052
D[Air-Con]
0.0306
0.0481
0.6359
0.5292
0.0245
0.0481
0.5103
0.6150
D[Suburb = Leichhardt]
−0.1471
0.0322
−4.5601
6.7E−05
−0.1149
0.0398
−2.8845
0.0086
D[Suburb = Paddington]
0.1188
0.0326
3.6425
0.0009
0.1174
0.0507
2.3171
0.0302
λ 1 T 1
−0.0711
0.0310
−2.2934
0.0283
−0.0057
0.0398
−0.1439
0.8869
λ 2 T 2
−0.0842
0.0295
−2.8555
0.0074
0.0345
0.0399
0.8659
0.3959
TABLE 6
Bias-Corrected Lamda
T = 1
T = 2
Standard
Bias
Standard
Bias
Lamda
Error
Corrected
Lamda
Error
Corrected
Estimate
(σ)
Lamda
Estimate
(σ)
Lamda
λ 1
−0.0711
0.031
−0.0712
λ 1
−0.0057
0.0398
−0.0057
λ 2
−0.0842
0.0295
−0.0842
λ 2
0.0345
0.0399
0.0345
TABLE 7
Hedonic House Price Index
Index
Status
Index
Status
(T = 1)
(T = 1)
(T = 2)
(T = 2)
March 2007
548.289
Base
548.289
Base
April 2007
510.630
Fixed
510.630
Fixed
May 2007
503.993
Indicative
507.710
Fixed
June 2007
528.577
Indicative | A method and system for generating a real estate property index uses real estate data including price data, property data and time of sale data that are entered into a computing apparatus. The time of sale data is manipulated to provide consecutive triple times giving two consecutive time periods (e.g., March, April, May 2007 and April, May, June 2007). A transform function, preferably a log function, is generated with two time dummy variables, and the coefficients of the two time dummy variables are extracted and added to generate a transformed growth rate. The reverse transform function, preferably an anti-log function, is generated to provide the desired untransformed growth rate. | 6 |
(a) Field of the Invention
This invention relates to child proof safety closures for use, for example, on bottles or canisters and the like.
(b) DESCRIPTION OF THE PRIOR ART
There are a wide variety of child proof safety closures which are used primarily for sealing containers holding medicinal agents, such as tablets, capsules and the like. Such closures generally depend upon a disguised method of opening the container so that in many cases even adults would have difficulty in opening the closure, until they are either informed of the secret or until they independently work out the solution.
However many children tend naturally to be very curious and persistent, and to protect such children against access to possibly harmful drugs, it is not enough that a safety closure merely be so ingeniously designed as to defeat a child's curiosity and persistence. The closure should also be designed so that it can defeat a child's physical strength as well, because even though a child may be unable to solve the riddle of how the closure should be normally opened, he will attempt to force his way into the container by whatever means will succeed.
One of the largest classes of safety closures is the type that could be characterized as the turn-and-lift type in which a closure cap is first rotated on the bottle until separate indicia on the bottle and the closure are in alignment with one another, and the cap is then lifted from the bottle using an appropriate lifting tab. In such closures, the cap rotation step in the required opening sequence is essential in order to bring various restraint and release means, located around the periphery of the cap and the bottle, into proper registry with one another before the cap can be removed.
Typical of such turn-and-lift caps are those shown, for example, in Powell U.S. Pat. No. 3,017,049; Graff U.S. Pat. No. 3,587,896; Horvath U.S. Pat. No. 3,627,160; Horvath U.S. Pat. No. 3,669,295; Robbins et al. U.S. Pat. No. 3,896,958 and McCord U.S. Pat. No. 4,043,474. However in each of these closures, and in all others of the same general type of which I am aware, the rim of the closure cap is left exposed, so that a determined and persistent child would be able to force either his finger nails or teeth under the edge of the cap and, by physical force, pry the cap from the bottle, even against all built in restraints intended to prevent such action. Known child proof closures of the type described therefore leave room for improvement to overcome the shortcomings described above.
BRIEF SUMMARY OF THE INVENTION
The safety closures provided by this invention overcome the disadvantages, as described above, inherent in conventional safety closures of the turn-and-lift type, because their design will defeat not only a child's inventiveness in solving the proper method for opening the closures, but they will as well defeat the normal strength of a child who attempts to physically force the caps from the container. These objects are accomplished by providing a safety closure of the general turn-and-lift class in which the closure element is of the plug type, and the container is provided with an upstanding annular rim above the neck thereof which completely covers the bottom portion of the closure plug and leaves only the upper portion of the plug exposed above the edge of the rim. Access, for example by the teeth or finger-nails, to the bottom edge of the plug is thereby prevented.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a bottle and safety closure plug unit according to the invention in combination.
FIG. 2 is a cross section view along section line II/II of FIG. 1 of one embodiment of the bottle and closure plug depicted in FIGS. 5 and 7.
FIGS. 3, 4 and 5 are top plan views of three different embodiments of bottles adapted for use in the practice of the invention as they would appear without the associated closure plugs.
FIGS. 6 and 7 are plan views of two embodiments of closure plugs according to the invention as viewed from the bottom.
FIGS. 8, 9 and 10 are views in cross section along section lines VIII/VIII; IX/IX and X/X of FIGS. 3, 4 and 5, respectively.
FIGS. 11 and 12 are views in cross section along section lines XI/XI and XII/XII of FIGS. 6 and 7, respectively, the plugs there depicted being shown in their right side up orientation.
DETAILED DESCRIPTION OF THE INVENTION
The invention will now be described in detail with reference to the foregoing figures, where like numerals are used to describe like parts.
FIG. 1 illustrates a bottle, identified by general reference numeral 10, having an associated closure plug 11. The closure plug is axially rotatable in the top of the bottle and is provided with a thumb tab 12. The latter serves both as an indicium for radial alignment with a second indicium 13 on the outside of the bottle near the top thereof and also as a thumb or finger bearing means for forcing the plug from the bottle when the two indicia 12/13 are in alignment.
With reference to FIG. 2, which illustrates the combination of the embodiment depicted in FIGS. 5 and 7 to be described below, it will be seen that the plug 11 is secured to the top of the bottle within an upstanding annular rim 14 above the neck of the bottle so that only the upper portion of the plug is exposed above the rim. The plug is held within the annular rim by engagement of a cooperating flange/groove means, 16/17, on the bottle and the plug, respectively, the flange being located around the inner periphery of, and at a level downward from the edge of, the annular rim.
In FIG. 2, the upper corner of the plug is shown as being chamfered slightly as at 15, although the corner may also be finished with a rounded corner. The important consideration in the nature of the edge of the plug is that, except for the tab 12, no sharp edge or corner should be provided on the exposed portion of the plug that could offer a good purchase for removal thereof.
The fundamental concept of the invention illustrated in FIGS. 1 and 2 is further illustrated by particular embodiments contemplated by the invention and represented by FIGS. 3-12. FIGS. 3, 4 and 5 show three embodiments of the bottle element provided by the invention. FIG. 6 shows, in bottom plan view, the closure plug to be used in combination with the bottle elements illustrated in FIGS. 3 and 4, while FIG. 7 shows, in bottom plan view, the closure plug to be used in combination with the bottle element illustrated in FIG. 5. Thus orientation of the plugs of FIGS. 6 and 7 with the appropriate bottles of FIGS. 3-5 is accomplished by rotating the plugs of FIGS. 6 and 7 180° about section lines XI/XI and XII/XII, respectively.
In the embodiment shown in FIGS. 3 and 6, a series of short flanges 16 around the inner wall of the upstanding annular rim 14 mate with an annular groove 17 around the mid-body section of the closure plug, this groove being best seen with reference to FIG. 11 and the flanges being best seen in FIG. 8. The lower body section of the plug is generally frustoconical in shape with an inwardly sloping wall section 18 which is interrupted by a flattened wall section 19. The plug is made of material having sufficient resilience to permit the closure plug to be snapped into the bottle opening, the flanges 16 sliding over the sloping wall section 18 and over the edge 20 thereof to thereby engage the groove 17.
The bottle indicium 13 is located on the outer face of annular rim 14 in radial alignment with one of the short flanges 16, and the thumb tab/plug indicium 12 is located in radial alignment with flattened wall section 19. Thus it will be seen that when the closure plug is oriented in the top of the bottle with the indicia 12/13, and therefore flange 16 and flattened wall section 19, out of registry with one another, the flanges will be entirely engaged with the annular groove 17, and the plug cannot be removed from the bottle. However when the plug is rotated so as to bring indicia 12/13, and cooperating release means comprising, in this embodiment, one of flanges 16 and flattened wall section 19, into registry, the flange which serves as the release means is able to move past flattened wall section 19 and thus, by upward pressure on thumb tab 12, the plug can be forced upward from the bottle.
A modification of the embodiment of FIGS. 3, 6, 8 and 11 is shown in FIGS. 4, 6, 9 and 11. In this embodiment, instead of a plurality of short flanges 16 as present in the embodiment of FIG. 3, the bottle is provided with a single short flange 16 and an extended flange 16' which extends around a major part of the inside periphery of the upstanding annular rim 14. In the embodiment of FIG. 4, the bottle indicium 13 is located in radial alignment with the short flange 16. The corresponding plug illustrated in FIG. 6, used in combination with the embodiment of FIG. 4, is fitted to, and removed from, the bottle in the same manner as described before with reference to FIGS. 3 and 6. However, in order to facilitate removal of the plug when short flange 16 and flattened wall section 19 are in registry, it is desirable to provide slightly rounded ends 21 to the extended flange 16' in order to permit the latter to more readily disengage from groove 17 as the plug is moved upward.
A further embodiment of the invention is illustrated in FIGS. 5, 7, 10 and 12. In this embodiment, a continuous flange 16" interrupted by a short gap 22 is provided around the inner periphery of annular rim 14. The mating plug, shown in FIGS. 7 and 12, is provided with an annular groove 17 for engagement with flange 16", but in this embodiment the frustoconical lower end of the plug which forms the inwardly sloping wall section 19 of the plug is cut away so that the groove 17 subtends a shorter arc of the plug periphery than that subtended by the embodiment of FIG. 6. The plug is further provided with a lug 23 in radial alignment with indicium/thumb tab 12, the lug being of such width that it can pass through gap 22. The closure plug is attached to, or removed from, the bottle in the same manner previously described, rotation of the plug to bring indicia 12/13 into alignment also bringing the cooperating release means, lug 23 and gap 22, into alignment with one another, so that by upward pressure on the thumb tab 12, the lug can pass through gap 22 permitting removal of the plug. The removal can be facilitated by providing slightly rounded edges on the ends of the sloping wall at the termination points of the groove to permit more ready disengagement of the flange 16" from the groove 17.
The closure plugs used in the practice of the invention are illustrated in the drawings with a hollow space 24 within the plug. This hollow space performs no critical function in the use of the plugs and is used only in the interest of economy of material. Thus solid plugs, having the proper resilience, will serve as well in the practice of the invention, and such solid plugs are therefore considered to be within the purview of the invention.
The bottles and the closure plugs provided by the invention are manufactured of materials conventionally used in this art. Thus the bottles can be fabricated of glass or of various plastic materials such as polystyrene, polyethylene or polypropylene, and the like, and the plugs can be fabricated of a variety of plastic materials, including vinyl rubbers, polyethylene, polypropylene and the like.
Having thus described the invention and the advantages thereof, it is considered that the invention is to be broadly construed and limited only by the character of the following claims. | A child proof safety container and closure is provided in which only a minimal portion of the top of the closure element, of the plug type, is exposed, and removal is effected by upward pressure against the plug only when cooperating release means in the closure and the container are in alignment. | 1 |
RELATED APPLICATIONS
[0001] This Application claims benefit of U.S. patent application Ser. No. AA/AAA,AAA, entitled, SYSTEM AND METHOD FOR TAX-ADVANTAGED ACCOUNT ADMINISTRATION, filed on Jul. 18, 2006 by Charles Marshall having the same assignee as this application and incorporated herein by reference in its entirety.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates to point-of-sale devices and methods, and more particularly to the real-time management of transactions from a tax advantaged and flexible spending accounts that use payment cards.
[0004] 2. Description of the Prior Art
[0005] Many years ago purchasing departments and employee benefits managers handled all aspects of business purchases of goods and services for their employees. This allowed tight control, but the system was also slow, cumbersome, and not at all responsive to real world needs. So the delivery of such goods and services was sped up by allowing the employees themselves to buy what was needed and then to submit an expense report or claim form. This however also proved to have a new set of problems, including the employee being out-of-pocket, purchases later determined to be unqualified, and fraud. The modern popularity of credit cards, debit cards, and point-of-sales terminals that can do real-time-authorization with the issuing banks of consumer financial transactions lead to other kinds of problems and abuses.
[0006] The employees and other uses did not limit themselves to authorized types of purchases, they had cards that were equivalent to cash and nothing outside their own self-control really limmited what they did with the cards. The larger problem was that it was not so clear what exact products and services were qualified expenses, even if the user was trying hard to comply with the rules and limitations. Many expenses need supporting documents to be submitted and retained to validate the expense later when audited or questioned. But since the provider was already paid, the motivation to generate or communicate these supporting documents got lost. Thus valid transactions could be disqualified for a lack of the required supporting evidence.
[0007] The Federal Government has complicated the administration of employee health and benefits programs by requiring complex qualifications of goods and services that need an expert to decipher. The rules also change from time to time, and one situation to the next can affect whether an expense is a qualified expense with tax advantages.
[0008] Conventional systems can sort out eligibility at a point-of-sale terminal, but there is an entire category of conditional items that are only eligible per other requirements and that are specific to the cardholder. These limitations can usually only be verified by communicating back to verify eligibility. The cardholder may also be eligible for certain promotions, discounts, additional funding sources, credit, etc.
[0009] Flexible spending accounts (FSA) can implement employee benefit accounts sanctioned by government authorities that offer tax advantaged employee benefits. Types of flexible spending accounts include those that cover healthcare, transportation, lodging, dependent care expenses, health savings accounts (HSA's), and healthcare reimbursement arrangements (HRA's), etc.
[0010] Conventional systems are now used for processing transactions initiated at a retailer or service provider. Many consumers still do not use their flexible spending accounts in over-the-counter transactions because the fielded systems are not configured to process such transactions. Flexible spending accounts have generally required submitting receipts and other paperwork to verify that the purchase was made for an item that was qualified under the flexible spending account. That prompted new systems to be built an auto substantiation function that could determine if a qualified product is being purchased, and thus is entitled to be paid for with funds linked to a flexible spending account card. Unfortunately, sometimes items are only conditionally qualified and can be deductible for only particular pre-qualified cardholders.
[0011] What is needed is a way to test if a conditionally qualified item is eligible to be paid for from a particular tax advantaged account, and to manage that in real-time from a point of sale device.
SUMMARY OF THE INVENTION
[0012] Briefly, a point-of-sale system embodiment of the present invention comprises a webserver that receives lists of products and services offered at retail points of sale, and that can sort them into items that are qualified, conditionally qualified, and non-qualified to be purchased by a cardholder using a flexible spending account payment card. The qualified items are permissible to be purchased by all cardholders, but purchases of conditionally qualified items are only permissible when the cardholder has registered a particular qualifying characteristic. For example, a health condition for which a doctor has prescribed the retail item for purchase. The demographics of the cardholders are available for affinity programs, promotional offers, discounts, and rebates. Such are proffered at the point of sale during transaction authorization to be considered by the cardholder or to be automatically exercised. Purchases in excess of the funds then available in the cardholders' flexible spending accounts can be deducted from other registered accounts or payrolls.
[0013] An advantage of the present invention is that the retail purchase of products and services only conditionally approved for purchase with tax-advantaged flexible spending accounts is automated.
[0014] These and other objects and advantages of the present invention will no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of the preferred embodiments which are illustrated in the various drawing Figs.
IN THE DRAWINGS
[0015] FIG. 1 is a functional block diagram of a point-of-sale (POS) system embodiment of the present invention;
[0016] FIG. 2 is a flowchart diagram of a method embodiment of the present invention that can be implemented as computer software to execute on retail POS terminals connected to a webserver over the Internet and related to flexible spending account payment card usage in the system of FIG. 1 ;
[0017] FIG. 3 is a flowchart diagram of a method embodiment of the present invention that can be implemented as computer software to execute on a workstation and manage the registration of retailers and their retail items related to flexible spending account payment card usage in the system of FIG. 1 ;
[0018] FIG. 4 is a flowchart diagram of a method embodiment of the present invention that can be implemented as computer software to execute on a workstation and manage the registration of cardholders, corresponding demographics, and their health conditions related to flexible spending account payment card usage in the system of FIG. 1 ;
[0019] FIG. 5 is a flowchart diagram of a method embodiment of the present invention that can be implemented as computer software to execute on a workstation and manage the registration of employers and their company policies related to flexible spending account payment card usage in the system of FIG. 1 ;
[0020] FIG. 6 is a flowchart diagram of a method embodiment of the present invention that can be implemented as computer software to execute on a workstation and manage the registration of promoters and their incentives related to flexible spending account payment card usage in the system of FIG. 1 ;
[0021] FIGS. 7A-7C are flowchart diagrams of a method embodiment of the present invention that can be implemented as computer software to execute on a workstation and manage the registration of promoters and their incentives related to flexible spending account payment card usage in the system of FIG. 1 ; and
[0022] FIGS. 8A-8B describe a system by all the entities that can be involved and interconnected by a network in support of an FSA POS system.
[0023] While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0024] FIG. 1 represents a point-of-sale (POS) system embodiment of the present invention, and is referred to herein by the general reference numeral 100 . The POS system 100 may be implemented as a computer program to be sold and installed on otherwise conventional computer systems or financial transaction network workstations, platforms, and hardware that communicate with the Internet. At least one part is installed and executed on a POS device 102 and another part is mounted on a network server 104 . Other supporting pieces may be installed or added later throughout the system. In some embodiments of the present invention, the computer programs for system 100 may be sold, licensed, or subscribed to with the aid of disks, downloads, and pre-installations on hard disk or flash memory. Such computer programs for system 100 may be divided into pieces for respective parts of the network.
[0025] In a very familiar scenario, a user 106 presents a payment card 108 at a merchant location 110 for payment of goods and/or services 112 . A transaction request 114 is transmitted by POS device 102 to the network server 104 . The network server 104 consults an authorized user list 116 , a qualified goods and services items list 118 , a merchant/provider list 120 , and a financial transaction processor 122 .
[0026] If the user, the items, and the merchant/provider are all acceptable, and the funds are on account, then a transaction approval message 124 is returned to the POS device 102 . The transactions are logged in a database and the account funds are debited from a corresponding flexible spending account (FSA) 126 . Supporting financial transaction details and management controls 128 are made available to company management, accounting, and the government taxing authority. If authorized by the employee, and if necessary to cover overdrafts of the FSA 126 , a payroll deduction is sent to employer payroll processing 130 . Affinity programs, like frequent flyer miles and club discount cards, can be supported in real-time with appropriate offers and promotions that display at the POS device 102 when the server 104 recognizes a targeted user 106 , product/service 118 , or class of users and items involved in a present transaction request 114 .
[0027] In some embodiments of the present invention, the goods and/or services 112 are uniquely identified with industry standard Universal Product Codes (UPC) and/or stock keeping unit (SKU) numbers. These are very often reproduced on labels with bar codes for electronic scanning and POS checkout.
[0028] The qualified goods and services items list 118 can include conditionally qualified items that depend, e.g., on who user 106 is and what qualifying characteristics related to the user have been registered and accepted. System 100 is able to verify and authorize the purchase of conditionally qualified items in goods/services 112 from data maintained in the authorized user list 116 . FSA 126 is therefore only debited for expenses authorized by the relevant government tax-authority, and is able to automatically discern legitimate buyers for conditionally qualified goods and services.
[0029] The remaining drawing Figs. illustrate how individual parts function to contribute to the overall purpose of the system 100 .
[0030] FIG. 2 illustrates a method embodiment of the present invention, referred to herein by the general reference numeral 200 . Method 200 includes a retail activity part 201 that operates on a number of POS terminals, and that communicates over a network connection 202 to a server part 203 which operates on a web server. A cardholder begins the process by presenting their FSA card 206 and retail purchase selections of products and/or services 204 . These provide machine readable data like magnetic stripes and barcodes that are input by POS device scanners in a step 208 . A step 210 assembles a financial transaction request message that includes identification codes for the cardholder, products, services, and merchant, and the retail prices for the products and/or services.
[0031] A step 212 receives the financial transaction request message over network 202 and gathers relevant information from its own databases about the cardholder's employer, FSA accounts, health conditions, company policies, and data related to the incentives, products, services, and merchant. A step 214 reports out any applicable incentives given the particulars of this transaction. A step 216 displays the incentive identity, terms, and values for the merchant and cardholder to consider.
[0032] A step 218 sorts out those products and/or service items that are qualified or conditionally qualified to be purchased by this cardholder using a corresponding FSA account. If conditionally qualified, a step 220 looks for health condition matches from a health condition lookup 222 that was triggered by step 212 . A step 224 computes the incentive discounts, the allowable FSA deductions, and the balances from an FSA account 226 . Step 224 summarizes the total for a step 228 which computes and displays the remainder due from the cardholder after all discounts and credits. A step 229 completes checkout at the POS 201 . A step 230 finalizes the accounting by adjusting the FSA 226 and debiting any overdrafts of the FSA, as previously authorized by the cardholder, from the cardholder's payroll account 232 . Such will appear on the cardholder's next paycheck as a payroll deduction.
[0033] FIG. 3 illustrates a retailer registration method embodiment of the present invention, referred to herein by the general reference numeral 300 . Each retailer 301 that will participate in the system 100 of FIG. 1 and the method 200 of FIG. 2 logs into a server 302 . A step 304 assigns each retailer 301 a unique identification code, e.g., a merchant code. A step 306 initiated by each retailer 301 transmits lists of the products and services that it offers to FSA cardholders. A step 308 goes through such lists and flags each product or service as qualified, not qualified, or conditionally qualified for purchase with the FSA of the cardholders. A step 310 stores the retail product/service lists and flags in a database. Thereafter, if the server 302 is simply provided the product/service identification code for a POS purchase by a cardholder, a simple lookup can be used to see if the product/service itself is qualified, not qualified, or conditionally qualified for purchase. Such product/service identification codes can also be used by the server 302 to determine if any promotional incentives are activated.
[0034] FIG. 4 illustrates a cardholder registration method embodiment of the present invention, referred to herein by the general reference numeral 400 . Each cardholder 401 that will participate in the system 100 of FIG. 1 and the method 200 of FIG. 2 logs into a server 402 . A step 404 presents a registration webpage on the Internet. A step 406 is used by the cardholder, and perhaps their employer too, to supply identifying information about the cardholder, the employer, the FSA, banking information, etc. A step 408 , in particular, provides confidential or sensitive health information about the cardholder that may support the purchase of qualified products using the FSA. A step 410 elicits option selections and permissions from the cardholder, e.g., if payroll deductions are to be permitted and if so what if any limits are to be applied. A step 412 stores all the responses, validations, and supporting documentation in a database. Thereafter, if the server 302 is simply provided the cardholder identification code for a POS purchase by a cardholder, a simple lookup can be used to invoke the corresponding employer policies, health conditions, FSA account, and payroll. Such cardholder identification codes can also be used by the server 402 to determine if any promotional incentives can be appropriately applied.
[0035] Each retail product and service is assigned a qualification code that indicates it as being qualified, conditionally qualified, or non-qualified for reimbursement. Qualified products are eligible for reimbursement for any cardholder from tax-advantaged accounts.
[0036] Conditionally qualified products are those that may be tax deductable, but only for certain cardholders with particular health conditions. For example, the user must have a health condition with a corresponding an approved use of the product. For example, cardholders with diabetes are approved to buy glucose monitors and supplies.
[0037] Non-qualified products are ones that cannot be paid with from funds from a tax-advantaged account. Alcoholic beverages are an example of a product that is never to be paid with from funds from a tax-advantaged account.
[0038] Health condition codes are assigned to each user, and qualification codes are assigned to each product. The cardholders and products they are buying have their respective codes matched at the time of purchase. Non-qualified products can be assigned a negative integer, e.g., −1. Qualified products can be assigned a code of zero. And conditionally qualified products can be assigned a whole range of positive integer numbers, and these will align themselves to health condition codes.
[0039] For example, a glucose test kit that assesses blood sugar levels may have its product identifier associated with a qualification code-5, e.g., for diabetics. Any cardholders who have established themselves as having diabetes may receive reimbursement from the tax-advantaged account for such products with code-5. Conditionally qualified products may be those meeting government regulations regarding that condition for the tax-advantaged account.
[0040] FIG. 5 illustrates an employer registration method embodiment of the present invention, referred to herein by the general reference numeral 500 . Each employer 501 that will participate in the system 100 of FIG. 1 and the method 200 of FIG. 2 logs into a server 502 . A step 504 assigns a unique employer identification code to each employer 501 . A step 506 transmits employer company policies as they relate to the use of cards 206 by employee cardholders and corresponding FSA's. A step 508 abstracts these policies into decision rules that a computer can apply to transaction requests. A step 510 puts these company policies into a database so they can be accessed by employer ID and/or cardholder ID later to make an authorization of a financial transaction.
[0041] A company policy, as used in step 506 , may consist of a set of guidelines to be applied to purchases related to an employee. For example, a company policy may include limits on paycheck advances, and the type of products for which a paycheck advance may be used. A unique company identifier is assigned for each company, and abstracts of corresponding company policies are stored for each in a relational database.
[0042] FIG. 6 illustrates a promoter incentive registration method embodiment of the present invention, referred to herein by the general reference numeral 600 . Each promoter 601 that will participate in the system 100 of FIG. 1 and the method 200 of FIG. 2 logs into a server 602 . A step 604 assigns a unique promoter and incentive number for use later when authorizing a financial transaction.
[0043] Incentives are received in step 608 from retailers, manufacturers, health care providers, or other parties. The information for each incentive is stored by step 610 . Each incentive may include product and/or retailer identifiers. A discount can be provided by a retailer, or a payment can be made to a retailer if the relevant product is purchased in the transaction at the POS device. The incentive can be restricted to cardholders matching predefined characteristics, e.g., cardholders with particular health conditions, cardholders employed by a certain company, cardholders who are over a certain age, cardholders who are members of a certain gym, etc. A qualification criteria for each incentive specifies the cardholder demographics required for the incentive to apply.
[0044] A characteristic may specify that the incentive will be presented in cases in which the product is qualified, or only when a particular condition code is already associated with the cardholder.
[0045] Incentives can include discounts from retailers, and payments made to retailers, and can be limited to specific retailers and cardholders. The incentive program can direct that a specific account to be charged for the incentive, and can cap the amounts involved.
[0046] Incentive program restrictions may also include, e.g., the first ten employees of a company, a dollar amount, or other criteria. The incentive amount or percentage may also be specified as part of any incentive.
[0047] Cardholder affinity identifiers can be used to identify particular cardholders to a retailer, the eligibility conditions for conditional qualifications, and permissions to allow any overages to be deducted from a cardholder's next paycheck.
[0048] Returning to FIG. 4 , each cardholder may scan in or otherwise submit documentation to support health conditions and other characteristics needed to buy conditionally qualified products or services. For example, proof of a health condition may require a diagnosis from a doctor. The cardholder may access a webpage at a computer web browser to then select one or more conditions from the list of possible conditions.
[0049] Conditions are flagged to the system as approved upon receipt of sufficient proof, the actual proof itself is not routinely accessible. In one embodiment, cardholders are selected at random and notified that they must submit proof of the conditions they claim. The conditions for such selected cardholder are not flagged as approved until sufficient proof is received.
[0050] If the available balance amount in a tax-advantaged account is exceeded in any one period, and permission has been registered, any overages may be automatically deducted from the cardholder's next paycheck. E.g., by selecting on a browser webpage, a “Please deduct qualified product overages from my next paycheck” option. The cardholder may set a dollar or percentage limit, or the cardholder may otherwise indicate that qualified or conditionally qualified costs that exceed some or all of the balance in the cardholder's flexible spending account may be deducted from the cardholder's next paycheck.
[0051] Any health condition information that may have been received at step 408 with documentation from the cardholder are reviewed, and approved or denied. The health conditions, and any submitted documentation, may be reviewed manually, for example, by an outside administrator.
[0052] If permission is received to deduct qualified product overages from a cardholder's next paycheck, a paycheck-deduction limit may be designated in step 410 . To designate the paycheck-deduction limit, a fixed amount or a percentage of the next paycheck for the cardholder may be designated as the paycheck-deduction limit. For example, the cardholder only allow qualified product overages to be deducted up to the full amount, twenty percent, or $200 maximum of their next paycheck.
[0053] The paycheck-deduction limit may be designated up to the limits of and in accordance with company policy information received at step 508 of FIG. 5 .
[0054] Any approved qualifying conditions and optional paycheck-deduction permissions and thresholds are stored in step 412 . It is later associated with the cardholder's tax-advantaged account identifier, optional administrator identifier cardholder affinity card identifiers, any qualifying conditional codes and the optional permission to deduct qualified product overages from the next cardholder paycheck with the paycheck-deduction limit. Any number of cardholders and companies with tax-advantaged accounts can managed by different plan administrators.
[0055] Cardholder registration information may be received from a cardholder at any time. Once a cardholder has submitted their registration information, they may be eligible to deduct the cost of qualified products from their tax-advantaged account.
[0056] FIGS. 7A-7C represent a method 700 of deducting the cost of qualified and conditionally qualified products from a cardholder FSA according to one embodiment of the present invention. In FIG. 7A , products are chosen in step 710 by a cardholder at a retailer location, such as at a supermarket, pharmacy, or drugstore.
[0057] The products chosen and a cardholder affinity card are presented in step 712 at a retailer location. A first chosen product is selected in step 714 by the retailer, for example, using a retailer point of sale (POS) computer system. To select the first chosen product, the retailer may identify the product identifier, such as the UPC or SKU number by scanning or manually entering it.
[0058] The retailer identifier, the card identifier of the affinity card provided by the cardholder in step 712 and the product identifier and price of the selected chosen product selected in step 714 are transmitted in step 716 to a server by the retailer, and the information is received in step 716 at the server. To transmit the retailer identifier, the affinity card identifier and the product identifier and price of the selected chosen product, the information may be transmitted over a network such as the Internet and received by the server.
[0059] If the product identifier is other than a UPC, the server uses the retailer identifier to look up the product list corresponding to the product code provided. Any applicable incentive or incentives are determined and reported in step 718 by the server from those received. To determine any applicable incentives for the selected chosen product that are applicable to the cardholder, the server may use the retailer identifier, product identifier and the affinity card identifier to determine whether any incentives received apply to the selected product. The affinity card identifier may be used to identify characteristics of the cardholder, such as employer identifier, to determine whether incentives dependent upon cardholder characteristics, apply to the transaction. If the incentive is a discount or payment for cardholders with certain characteristics for products purchased from a certain retailer or retailers, the server determines whether the retailer identifier matches that stored with the incentive, and if so whether the cardholder has all of the characteristics, if any, specified for the incentive, and if so, applies the discount. If the incentive is from a party other than the retailer, and is applicable to any retailer, the server determines whether the product identifier corresponds to any incentives, and if so, whether the cardholder characteristics match all of the characteristics, if any, specified in any such incentive.
[0060] The server reports any applicable incentive amounts back to the retailer in any conventional manner, for example over a network such as the Internet. The incentive amount may be a fixed amount or a percentage or other variable amount based on the price of the product, such amount being specified with the incentive. In one embodiment, each incentive may have text associated with the incentive, and such text is provided with the amount of any applicable incentives so that the retailer can display the text at a display screen or on the receipt.
[0061] The incentive amounts, and the price of the selected product, minus any reported applicable incentive amount, may be displayed in step 720 by the retailer. Discounts that have been subtracted from the original price are displayed in any conventional manner, such as on a cash register display. The text corresponding to the incentive may also be displayed as part of step 720 .
[0062] The qualification status of the selected product for the current cardholder is determined in step 754 by the server. To determine the qualification status of the selected product, the UPC of the selected product may be used to retrieve the qualification code or codes associated with the selected product in a qualification table.
[0063] If the selected product is a qualified product in step 732 , the method continues at step 740 of FIG. 7B . A qualified product is a product that is eligible to be deducted from a tax-advantaged account, if the product is designated as a qualified product without conditions. The selected product may be determined to be a qualified product without conditions if the qualification code associated with the selected chosen product is zero.
[0064] If the selected chosen product is not a qualified product in step 732 , but the selected chosen product is a conditionally qualified product in step 734 for which the account holder qualifies in step 736 , the method continues to step 740 . The selected product may be determined to be a conditionally qualified product if the qualification code or codes associated with the selected chosen product include any positive number.
[0065] The cardholder is assumed to qualify for the conditionally qualified product if the code for any required condition for that product has been stored as part of the cardholder registration information for the cardholder. For example, if a cardholder is approved and documented as being a diabetic, the cardholder may be conditionally qualified for one or more products eligible to be deducted from the tax-advantaged account of a cardholder who is a diabetic, e.g., a kit for testing a cardholder's blood sugar levels. A cardholder has the condition for which a product is qualified if the condition code of the product matches or corresponds to the same code in the cardholder information.
[0066] Otherwise, if the selected chosen product is neither a qualified product in step 732 nor a conditionally qualified product in step 734 , or if the selected chosen product is a conditionally qualified product in step 734 for which the cardholder is not qualified in step 736 , the method continues to step 776 of FIG. 7B .
[0067] At step 740 , the balance of the cardholder tax-advantaged account is checked by the server. To check the balance of the cardholder tax-advantaged account, the identifier of the affinity card or credit card provided by the cardholder at step 712 may be used to request and receive the account number and administrator identifier of the cardholder tax-advantaged account. The account number is sent to a server operated by that administrator, and the balance of that account is received. The administrator is a third party, an entity different from and not majority owned by, or not a majority owner of, the party that performs step 740 , or the administrator of the account the same party as the party that performs step 740 , or a party that controls or is controlled by that party.
[0068] In one embodiment, to the extent that funds are available in the tax-advantaged account, if the product is qualified for the cardholder, either because the product is unconditionally qualified, or the product is conditionally qualified for the condition the employee has, the amount of those funds, up to the remaining price of the product, is reported as a further discount to the retailer so that the retailer can properly compute the remainder, if any, which is the amount the cardholder must pay for the product, and may optionally display these amounts to the cardholder. The amount of the funds to apply from the tax-advantaged account is reported as a further discount, referred to as the tax-advantaged account discount, in a manner similar to the incentives described above. This allows the retailer to separately print or display both the incentive amount and the amount applied from the tax-advantaged account, yet treat them both as a discount to the purchase price of the product, to be deducted from the price to be charged the cardholder at the point of sale terminal.
[0069] A hold is placed on the tax-advantaged account in the amount of the tax-advantaged account discount until the retailer confirms that the check out process is complete. The product is recorded as having been purchased and the tax-advantaged account is charged for the product when the product identifier is received. In the event that the check out process is not completed, the transaction is reversed from the tax-advantaged account.
[0070] In FIG. 7B , if the balance of the cardholder tax-advantaged account minus any hold amount currently corresponding to the cardholder tax-advantaged account is greater than zero in step 760 , the tax-advantaged account discount applicable to the selected chosen product is identified. The amount of the tax-advantaged account discount is added as a hold amount for the cardholder tax-advantaged account, and the current time and date is added to the hold amount in step 762 . To identify the amount of the tax-advantaged account discount, either the price of the selected chosen product reported and displayed at step 718 and 720 of FIG. 7A . The full price minus any retailer discounts is identified as the tax advantaged account discount, or if that price is greater than the balance minus the hold amount left in the cardholder tax-advantaged account, the remainder of the balance minus the hold amount is identified as the tax-advantaged account discount.
[0071] For example, if a selected product that costs twenty dollars is eligible to be deducted from the cardholder tax-advantaged account, and the total balance of the cardholder tax-advantaged account exceeds twenty dollars, then the tax advantaged account discount is the full price of the product, or twenty dollars. However, for that same twenty-dollar selected product, if the total remaining balance of the cardholder tax-advantaged account is only ten dollars, then the tax-advantaged account discount is set to ten dollars.
[0072] The identified tax-advantaged account discount amount is added to a hold amount on the cardholder tax-advantaged account. It may not be deducted from the actual tax-advantaged account. For example, in case the cardholder changes their mind about purchasing the product at a later time before completing check out.
[0073] The transaction is stored, and includes the product identifier, cardholder identifier, incentives, and tax-advantaged account discount to apply to the product price, the current time and date. The identifier of each incentive may be added at the time the information regarding the incentive is stored.
[0074] If there is a remainder in step 764 after the tax-advantaged account discount has been applied to the hold amount on the cardholder tax-advantaged account, such remainder being the balance of the tax-advantaged account minus the hold amount on the tax-advantaged account is not sufficient to cover the full cost of the selected product, permission may have been recorded for the cardholder at step 236 of FIG. 2B to deduct any qualified product overages from the cardholder's next pay check.
[0075] If permission was recorded in step 770 , and the amount of the paycheck deduction does not exceed the paycheck deduction limit identified for the cardholder at step 234 of FIG. 2B or any limit set forth in the company policy for the company corresponding to the company identifier of the cardholder, the remainder, to the extent either paycheck-deduction limit has not been exceeded, may be calculated in step 774 as a paycheck discount for the cardholder. The amount of the paycheck discount is added in step 774 to a deduction amount to be applied to the cardholder's next scheduled paycheck.
[0076] If a product is not qualified and not qualified for the cardholder, the entire amount of the purchase price for such product is treated as an overage. As illustrated by the dotted line from connector-C to step 770 of FIG. 7B , such overages for non-qualified products for the cardholder may be deducted from future cardholder paychecks, in the manner described above, even if the products are not qualified products.
[0077] In step 776 , any applicable incentive, tax-advantaged account, and paycheck discounts are reported by the server to the retailer. The total discount is reported by the server to the retailer over a network such as the Internet. The price, UPC code corresponding to the product identifier, transaction identifier, amount of any discounts, and the account number of any incentives, are stored as a pending product record, along with a transaction identifier and an order identifier for all products purchased together by the cardholder.
[0078] The final price of the selected chosen product is displayed in step 750 by the retailer. To display the final price of the selected chosen product, the retailer may display and/or apply the discount or discounts for the selected product received from the server and/or display the original price of the selected product.
[0079] If the cardholder has provided no more chosen products to the retailer that the retailer has not yet selected and transmitted to the server in step 752 , the method continues to step 780 of FIG. 7C .
[0080] Retailers may provide identifiers of products one at a time, to allow the price and discounts to be displayed as they are rung up. However, rather than receiving and providing the information described herein for each product at a time, the same process may be performed with the retailer providing the product identifiers several at a time, for example, after the products have been scanned but before they have been paid for.
[0081] Paycheck discounts can be totaled, but not applied until the cardholder enters a personal identity number (PIN). The cardholder can also enter an amount to be used for the paycheck discount if less than all of the eligible amount is to be used. The retailer may receive the PIN and optionally, the amount, and provide it to the server for this purpose.
[0082] To identify the products that correspond to a single order, an order identifier may be provided by the retailer for each product that is part of an order, the order identifier being originated by the retailer or by the party receiving the product identifiers. Other ways of identifying a single order may be used, such as using the source Internet Protocol (IP) address and port identifiers that may be provided with the product identifiers. The retailer can handle the provision of a separate IP address and port, either by providing one for each cash register, either directly or using a type network address translation function provided by a server, in which the server uses a different IP address and port identifier to identify each currently pending order. The operation of the method by the retailer may only require minimal additional programming. A watchdog timer, or an indication that a product identifier is the first of an order, can be used to detect problems, such as when a cash register is being reset in a manner in which product identifiers from a previous order may be retransmitted from the retailer.
[0083] If the cardholder has provided one or more chosen products to the retailer that the retailer has not yet selected and transmitted to the server in step 752 , the retailer selects the next chosen product in step 754 , and the method continues at step 716 with the newly selected chosen product.
[0084] FIG. 7C continues from FIG. 7B , and illustrates a method of deducting qualified expenses from a cardholder tax-advantaged account. If the retailer has scanned the last product chosen by the cardholder in step 752 , the retailer identifier and the cardholder affinity card identifier are transmitted in step 780 to the server by the retailer, along with a check-out indication and the total amount of the expected discounts that the retailer expects to receive from those described above. The check-out indication may be transmitted as flag, for example a “calculate total” flag. The transaction identifier is also included or implied.
[0085] The retailer identifier, the cardholder affinity card identifier, the check out indication, the total expected discount and the transaction identifier are received in step 782 at the server. The current date and time are retrieved in step 784 , and the retrieved date and time are compared in step 784 to the date and time of the first time-stamped transaction that is recorded for the cardholder for the transaction identifier. If the date and time of the check out attempt is not within a specified hold period in step 786 , the method continues in step 794 . The hold period may be a length of time specified by the tax-advantaged account administrator of the cardholder tax-advantaged account corresponding to the cardholder affinity card identifier, or the hold period may be specified by another administrator.
[0086] If the date and time of the check out attempt is within the specified hold period of the current date and time in step 786 , the current check out total expected discount received from the retailer is compared in step 788 to the total expected discount calculated at the server. The total expected discount is calculated at the server as the summation of all discounts applicable. If the two expected discount totals are not the same in step 790 , an error is indicated to the retailer in step 798 .
[0087] If the two expected discount totals are the same in step 790 , the total discount is returned in step 792 to the retailer along with an authorization code and the current date and time.
[0088] The authorization code is provided to the retailer with the current date and time so that the retailer may optionally store the information for its records.
[0089] In step 792 , an instruction is sent to the administrator of the cardholder tax-advantaged account to deduct the appropriate amount from the cardholder tax-advantaged account and to release the hold on the cardholder tax-advantaged account. The total expected tax-advantaged account discount for the transaction, which does not include any expected deductions from future cardholder paychecks, is provided with the authorization code to the tax-advantaged account administrator with an instruction to deduct that amount from the cardholder tax-advantaged account. The tax-advantaged account administrator is instructed to release the hold corresponding to a current transaction that had previously been placed. Any incentive accounts are charged for incentives corresponding to the order, as part of step 792 , using an order number from pending product records.
[0090] A hold on the tax-advantaged account may expire. This allows a transaction that is interrupted without completion to be automatically released. Step 794 is used when the hold has expired before the transaction is complete.
[0091] In step 794 , the account administrator is messaged to release the hold on the tax-advantaged account, and the current balance of the cardholder tax-advantaged account is again retrieved from the tax-advantaged account administrator. The hold is released and the current balance is retrieved to ensure that sufficient funds are still available in the cardholder tax-advantaged account to cover the costs that are to be deducted from the cardholder tax-advantaged account. For example, to ensure that other transactions are not concurrently being deducted from the cardholder tax-advantaged account, that would result in insufficient funds. If the newly retrieved balance of the cardholder tax-advantaged account is not sufficient to cover the deductions expected from the current transaction in step 796 , an error is sent to the retailer in step 798 .
[0092] If the newly retrieved balance of the cardholder tax-advantaged account is sufficient to cover the deductions expected from the current transaction in step 796 , the tax-advantaged account administrator is requested in step 799 to put a new hold on the cardholder tax-advantaged account. The method continues to step 788 .
[0093] FIGS. 8A and 8B describe a system 800 by all the entities that can be involved and interconnected by a network 802 . A communications interface 808 is private to a retailer manager 810 . System 800 further includes a retailer information storage 812 , a qualification manager 814 , a qualification information storage 816 , a health condition list manager 820 , a health condition list storage 822 , a company policy manager 830 , a company policy storage 832 , a retailer discount manager 840 , a retailer discount storage 842 , an employee registration manager 850 , an employee registration storage 852 , a health condition approval manager, a flexible spending account (FSA) discount manager 860 , a qualification status identifier 862 , an alternate payment manager 864 , a transaction verification manager 870 , a hold check manager 872 , an authorization manager 874 , a re-hold manager 876 , an error manager 878 , a plurality of retailer POS terminal systems 880 , and an FSA balance manager 890 . Special communication interfaces 882 and 892 are provided for secure communications.
[0094] Although the present invention has been described in terms of the presently preferred embodiments, it is to be understood that the disclosure is not to be interpreted as limiting. Various alterations and modifications will no doubt become apparent to those skilled in the art after having read the above disclosure. Accordingly, it is intended that the appended claims be interpreted as covering all alterations and modifications as fall within the “true” spirit and scope of the invention. | A point-of-sale system comprises a webserver that receives lists of products and services offered at retail points of sale, and that can sort them into items that are qualified, conditionally qualified, and non-qualified to be purchased by a cardholder using a flexible spending account payment card. The qualified items are permissible to be purchased by all cardholders, but purchases of conditionally qualified items are only permissible when the cardholder has registered a particular qualifying characteristic. For example, a health condition for which a doctor has prescribed the retail item for purchase. The demographics of the cardholders are available for affinity programs, promotional offers, discounts, and rebates. Such are proffered at the point of sale during transaction authorization to be considered by the cardholder or to be automatically exercised. Purchases in excess of the funds then available in the cardholders' flexible spending accounts can be deducted from other registered accounts or payrolls. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a novel process for the oxidation of methane and a wide range of hydrocarbons in the liquid phase in the presence of air or oxygen catalyzed by complexes of ruthenium activated by the presence of an end-or bridged oxo group along with carboxylato groups. This process provides a high yield with good catalytic turnover efficiency.
2. Background of the Invention
The oxidation of alkanes such as methane, ethane, propane, butane and the like can be difficult to achieve. Methane can be especially difficult to oxidize. Many methods have been developed to oxidize methane and other hydrocarbons. However, these methods generally produce very low yields of oxidation product and utilize expensive catalysts which must be replenished frequently. The use of metalloporphyrin catalysts such as Fe(TPP)C1 and Mn(TPP)C1 (where TPP=the dianion of 5,10,15,20-tetraphenylporphine) with iodosyl benzene, sodium hypochlorite and alkyl hydroperoxides or other costly nonregenerative oxidants has been reported. [P. Traylor, D. Dolphin and T. Traylor, J. Chem. Soc. Chem. Comm., 279 (1984), J. Groves, W. Kruper, Jr., R. Hanshalter, J. Am. Chem. Soc. 102, 6377 (1980), J. Smegal and C. Hill, Ibid, 105, 3515 (1983).] Oxidation of a variety of hydrocarbons other than methane has been achieved by the use of the binuclear Fe(III)-μ-oxo-μ-acetate complexes in the presence of the oxidant, t-butyl hydroperoxide and O 2 . [J. B. Vincent, J. C. Huffman, Chiston, Q.Li, M. A. Nancy, D. N. Hendrickson, R. H. Fong, R. H. Fish. Ibid, 110, 6898 (1988)]. [C. Chin and D. T. Sawyer, Ibid 112, 8212 (1988)]. These methods are expensive and the reagents are nonregenerative.
Azide-activated complexes of several metals in the presence of ligands such as TPP, and acetylacetonates and air or molecular oxygen have been used to catalyze the oxidation of isobutane, propane and cyclohexane at 70°-180° C. and 20-170 atmospheres in the liquid phase. The catalysts are inactive in the absence of the azide. [U.S. Pat. Nos., 4,895,680 and 4,895,682].
Heteropoly acids with site specific framework have also been used for the oxidation of alkanes in the liquid phase in the presence of oxygen at 125°-175° C. and 170 atmospheres. With such a method propane can be oxidized to acetone and isopropyl alcohol [U.S. Pat. Nos., 5,091,354 and 4,898,989]. Cyano-substituted and nitro-substituted metalloporphyrins have been used for the oxidation of isobutane to isobutyl alcohol at 70°-180° C. and about 25 atmosphere of pressure.
In these systems, the ligands are costly compounds and the recyclability of the catalysts remains questionable. In addition, although methane is included in the general list of hydrocarbons that can be oxidized, the oxidation of methane is not specifically discussed or illustrated. [U.S. Pat. Nos., 5,118,886 and 5,120,882].
The gas phase oxidation of natural gas to methanol by molecular oxygen in the gas phase has been disclosed by Walker et al. [U.S. Pat. No. 2,007,116] and by Gesser et al. [U.S. Pat. No. 4,618,732]. In the latter case, a 13% conversion of natural gas (composition not mentioned) was claimed at 300°-500° C. and 10-100 atmospheres. V. A. Durante et al. [U.S. Pat. Nos. 4,918,249 and 5132472] used silicometallates as catalysts for the gas phase oxidation of methane to methanol at 300°-600° C. and 10-70 atmospheres. A 7% conversion of methane to the oxidation products methanol and CO 2 was reported. With a reaction column filled with sand or inert refractory inorganic particles, Scott Hans [U.S. Pat. No. 4,982,023] disclosed a 5.5% conversion of methane to methanol at 300°-500° C. and 10-100 atmospheres. With a ZSM-5 packing, a direct conversion of methane to aromatics was reported at 300°-500° C. and 5-100 atmospheres [U.S. Pat. No. 5,012,029].
It is therefore to be noted that except for the gas phase oxidation of methane to methanol, which involves large energy inputs and low yields, a truly catalytic low energy liquid phase oxidation of methane to methanol has not yet been achieved.
It is therefore an object of this invention to provide a truly catalytic process for the oxidation of methane and other hydrocarbons to alcohols, ketones and other such products, which uses air or oxygen, and a metal coordination complex as a catalyst, and which requires low energy input, produces high conversion rates and has high product efficiency.
Another object of this invention is to provide a process for oxidation of methane and other hydrocarbons where a truly catalytic cycle is achieved with the active catalyst having a high turnover efficiency.
A further object is to provide a process for oxidation of methane and other hydrocarbons where there is no need for the addition of expensive compounds to regenerate the catalyst or for the use of non-regenerable oxidants.
DESCRIPTION OF THE INVENTION
This invention involves a process for the economical and efficient oxidation by hydrocarbons. This invention is particularly applicable to the oxidation of methane to methanol, which is known to be more difficult to oxidize than other alkanes. The invention is however, equally effective for the oxidation of other classes of hydrocarbons.
Although the process is effective for a wide variety of hydrocarbons, it is particularly effective for the oxidation of alkanes, cycloalkanes and related compounds, including straight chain and branched chain hydrocarbons with 1 to 15 carbon atoms. The preferred hydrocarbons have 1 to 10 carbon atoms, such as methane, ethane, propane, butane, isobutane, hexanes, and heptanes; and, cyclic hydrocarbons with 5 to 10 carbon atoms such as cyclopentane, cyclohexane, cyhcloheptane, cyclooctane and adamantine. Aromatic hydrocarbons such as toluene, xylene and ethylbenzene can also be oxidized, specifically on the side chain.
The oxidation products are known alcohols or ketones that have several applications. Methanol, the product of the oxidation of methane, is particularly important as a petroleum additive, source of C 1 chemicals and as a solvent. The process of this invention is also applicable for the further oxidation of partially oxidized hydrocarbons to organic acids.
Thus, this invention is applicable to a broad range of hydrdocarbons which may contain various substituents to enhance the rate of oxidation. The nature of these substituents may be decided by users well versed in the art. The oxidation of methane represents the most important and preferred application of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The oxidation of hydrocarbons by this process of this invention is catalyzed by various ruthenium coordination complexes. The active catalytic species may best be defined as an end-oxo or bridged-oxo complex with the following structures: ##STR1## where L is a Schiff base such as saloph, hydroxy-Acetoph, salen, accac or the like or is a substituted Schiff base, as shown in the following structures: ##STR2##
The end-oxo complexes LRu=O can be synthesized by the following steps. The chloro Schiff base complex RuLCl 2 and iodosyl benzene are dissolved in equimolar quantities in waterdioxan/dimethyl formamide (DMF). The resulting solution is stirred at room temperature for six to eight hours. The iodobenzene liberated is extracted with diethyl ether. The solution is then evaporated to a small volume and the oxo complexes precipitated with diethyl ether.
The starting complex RuLCl 2 is obtained by refluxing equimolar quantities of the Schiff base ligand L and the complex K 2 [RuCl 5 .H 2 O] (synthesized from RuCl 3 .xH 2 O and concentrated HCl [M.M.Taqui Khan, Ch Sreelata, S.A.Mirza, G.Ramachandriah and S.H.R.Abdi, Inorg. Chim. Acta, 154,103(1988)]) in ethanol for about 10-15 hours in an argon atmosphere. After completion of the reaction as checked by TLC, the solution was filtered in an argon atmosphere and concentrated to about one-quarter of its volume. The RuLCl 2 is precipitated by diethyl ether or ethylacetate and then recrystallized from ethylacetate.
The dimeric bridged-oxo ruthenium complex can be synthesized by refluxing one mole of RuCl 3 .x H 2 O in a 1:1:1 water/carboxylic acid/ethanol mixture with two moles of the Schiff base for 30 to 60 minutes, until a solid is obtained. The solid is then dissolved in the minimum amount of water on warming and left overnight until a purple solution is obtained. The bridged-oxo ruthenium complex is then precipitated with acetone-ether. Yields are 30-50%.
Oxidation according to this invention is carried out in a liquid phase, mixed solvent system such as water/acetone, water/acetonitrile and/or acetic acid, which is inert to the conditions of the reaction and to oxidation by molecular oxygen. The temperature can range between 20°-60° C. The pressure may range from 5 to 20 atmospheres. In the preferred embodiment of this invention, the temperature equals 30° C. and the pressure is 14 atmospheres.
Depending upon whether the hydrocarbon is a solid, liquid or gas, it is either dissolved in the mixed solvent system or is bubbled through the solvent together with air or oxygen. The catalyst is then added. A concentration of range 10 -3 to 10 -6 moles of catalyst in solution is sufficient to yield the desired product. The catalyst forms a homogeneous solution with the solvent and is not destroyed during several turnovers of the reaction. The time of reaction is generally from 30 minutes to 30 hours. The preferred reaction time is 1 to 5 hours.
The nature of the solvent, though not critical, can effect the time of reaction. In gases, where the solubility of the gas in the solvent is an important parameter, the specific solvent used will have a greater role in the reaction rate. Solubility will also depend on the temperature and pressure. Optimum conditions need to be determined for each case. Water/acetone is the preferred solvent for the oxidation of methane.
The ratio of the various reactants can vary widely and is not critical. The concentration of the catalyst can range from 10 -3 to 10 -6 moles of catalyst per mole of hydrocarbon used. The amount of oxygen can vary between 10 -3 to 10 -2 moles O 2 per mole of substrate. Care must be taken since some of the factors may fall within explosive limits.
The oxidation process of this invention can also be carried out without a solvent. The hydrocarbon to be oxidized is placed in contact with air or molecular oxygen and the ruthenium metal catalyst.
EXAMPLE
Oxidation of Methane
An oxo-bridged dimeric ruthenium complex, described above where the Schiff base, L is saloph and R is CH 3 , was prepared by the procedure described above. This complex was dissolved in a 1:1 water-acetone solution to a concentration of about 10 -3 M. The required quantity of solution was transferred to a glass lined Parr reactor. The reactor was pressurized with a CH 4 :O 2 mixture (oxygen 20%) to 14 atmospheres. The temperature was 30° C. The mixture was stirred and the methanol produced was analyzed chromatographically every hour. A yield of 0.12 moles of methanol was obtained after 12 hours. The conversion of the methane to methanol by this process is 80%, the maximum reported so far. The amount of CO 2 formed was 0.01 moles, showing more than 90% efficiency in the conversion to methanol. The catalyst turnover rate for this reaction was 12 moles of methanol produced per mole of the catalyst per hour. | This invention teaches the oxidation of alkanes and cycloalkanes in the presence of air or oxygen and a ruthenium metal complex catalyst containing an end or bridged-oxo group with a liquid L and carboxylato groups. This oxidation process results in very high yields, utilizes very little energy and has a high catalyst turnover rate. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Patent Application No. 60/325,249, filed Sep. 26, 2001, which is incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates generally to data communications, and specifically to high speed data communications transferred as packets.
BACKGROUND OF THE INVENTION
A data receiver needs to be able to receive and process incoming packets sufficiently quickly so that there is no significant buildup, or bottleneck, at each stage of the processing. Such bottlenecks have occurred because of, for example, a relatively large number of operations required to be performed by a central processing unit (CPU). As the speed of CPUs has increased, more than compensating for these bottlenecks, the bottlenecks have moved to other places in the processing chain.
The Transport Control Protocol (TCP) is a connection based packet protocol between two endpoints. Each endpoint needs to perform a set of operations, termed TCP termination, on receiving TCP packets in order to support the protocol. Typically, until relatively recently, TCP termination operations have been performed in software, under direction of a CPU. As data transfer rates have increased such software driven terminations have become bottlenecks, and have been transferred to hardware, typically in the form of a printed circuit card or an application specific integrated circuit (ASIC). Hardware for performing the terminations is termed a TCP off-load engine (ToE).
Terminating hardware such as a ToE is typically coupled to an Ethernet network. The hardware strips off headers from incoming packets, and transfers the payload of the packets to a host system. The payload is stored in a first, data, memory until the host system accepts it, or until missing packets have been received by the ToE, so that the ToE can send the data to the host in the original transmitted order. The size of the data memory needed is proportional to the product of the network rate and the network round trip delay (since all incoming data has to be acknowledged), leading to the need for large, of the order of hundreds of megabits, memories. Such memories are not practical for current ASIC technologies. In addition to requiring large memory size, memories for terminating hardware need fast access rates, since received data has to be written into, then read from, the memory at the network rate. If the memory is also used for temporarily storing transmitted data, the latter also has to be written into, then read from, the memory. The memory thus needs an access rate of the order of four times the network rate.
The headers comprise Ethernet, Internet Protocol (IP), and TCP layers, as well as optional higher layers such as an Internet Small Computer System Interface (iSCSI) layer. A second, context, memory acts as a database of connections maintained by the host system, the database comprising parameters for the state of each connection. The context memory, for example, maintains the last sequence number of received TCP segments. Other layers, such as the iSCSI layer, require the context memory to maintain parameters relevant to these connections.
For a system having relatively few connections, the context memory may be implemented within an ASIC as an on-chip memory. When larger numbers of connections need to be supported, the context memory may require use of an external memory. When external memory is used, the access rate to the external memory becomes an important consideration. The access rate is linearly dependent on the incoming packet or segment rate, and this is variable. For example, if a large numbers of short packets are received, the incoming packet rate, and hence the external memory access rate, is high. In order to implement such high access rates, very large numbers of data bus pins must be used, and such large numbers may be difficult to implement. Thus, an efficient hardware implementation of a ToE requires high access rates both for context and data memories, and such an implementation may be costly and may not even be practical for the high efficiencies required.
SUMMARY OF THE INVENTION
The present invention seeks to provide more efficient utilization of memory by a packet off-load engine, by using a single memory as both a context information and a payload data memory. Since context access and payload access rates are approximately inversely proportional, the single memory enables high access rates for both context and payload access, and such a single memory may be implemented in practice.
In preferred embodiments of the present invention, a packet off-load engine acts as an interface between a data network, a target, and a single memory external to the engine. The single memory stores payload data and context information of data packets transmitted between the network and the target. The off-load engine comprises an arbiter which arbitrates between write-payload, read-payload, write-context, and read-context requests to the memory, herein termed read-write memory requests. The arbiter comprises a context/payload memory access multiplexer, the multiplexer being able to transfer context information or payload data between the single memory and the engine. The multiplexer transfers the context information or the payload data according to a specific read-write request which the arbiter, after performing its arbitration, conveys to the memory.
The off-load engine is most preferably configured to have a receiver section which processes data packets received from the network for the target, and a transmission section which constructs data packets for transmission to the network from the target. The receiver section terminates a packet received from the network by stripping the header from the packet, and writing the packet's payload data to the memory, via the arbiter. Parameters in the stripped-off header are compared with context information, read from the memory via the arbiter, so that a correct disposition of the payload to the target may be implemented, and so that the context information may be updated as necessary and written to the memory.
The transmission section generates a packet to be transmitted to the network, for a payload received from the target, by reading context information from the memory via the arbiter. The transmission section generates a header based on the context information and on the payload, and appends the header to the payload to form the packet to be transmitted. After transmission of the packet, the transmission section writes an updated context to the memory via the arbiter.
By arbitrating between read and write, context and payload, transfers (four operations), preferred embodiments of the present invention provide an efficient system for performing such transfers between a single external memory and the off-load engine. The efficiency is a result of the approximately inverse relationship between the bandwidth requirements of context transfer and payload transfer—packets with small payloads requiring relatively higher rates of context transfer and relatively lower rates of payload transfer, compared with packets with large payloads that require relatively lower rates of context transfer and relatively higher rates of payload transfer. Furthermore, when the off-load engine is implemented as an integrated circuit device, the number of pins needed by the device can be significantly reduced, relative to devices known in the art, since the device need be coupled to only a single external memory using a single address bus, rather than to separate context and payload memories having separate address busses.
There is therefore provided, according to a preferred embodiment of the present invention, an off-load engine for processing a data packet conveyed between a target device and a network over a transport connection, the data packet including a payload and a header, the engine including:
a payload buffer, for holding data that is exchanged between the off-load engine, the network, and the target device for inclusion in the payload; a packet processor, for processing context information with respect to the transport connection; a context buffer, for holding the context information that is processed by the packet processor; a memory access multiplexer, which is coupled to convey the data in the payload buffer and the context information in the context buffer to and from a single memory that stores both the data and the context information; and an arbiter, which is adapted to control the multiplexer by arbitrating among payload requests to convey the data between the payload buffer and the single memory and context requests to convey the context information between the context buffer and the single memory.
Preferably, at least one of the payload buffer, the packet processor, and the context buffer, generate at least one of the payload requests and the context requests responsive to receiving the data.
Preferably, the payload requests include a write-payload-to and a read-payload-from request to the single memory, and wherein the context requests include a write-context-to and a read-context-from request to the single memory.
Preferably, the packet processor controls operation of at least one of the payload buffer, the context buffer, the multiplexer, and the arbiter.
Preferably, the packet processor receives the data packet from the network, strips the header from the data packet so as to provide the data for holding in the payload buffer, and routes the payload to the target device responsive to the context information. Further preferably, the packet processor receives the payload from the target device, generates the header responsive to the context information, appends the header to the payload to form the data packet, and transmits the data packet to the network.
Preferably, the payload buffer includes at least one receiver payload buffer for holding the data responsive to receiving the data packet from the network and at least one transmitter payload buffer for holding the data responsive to transmitting the data packet to the network, the packet processor includes at least one receiver packet processor for processing the header together with the context information responsive to receiving the data packet from the network so as to generate processed received context, and at least one transmitter packet processor for processing the header together with the context information responsive to transmitting the data packet to the network so as to generate processed transmitted context, and the context buffer includes a receiver context buffer for holding the processed received context and a transmitter context buffer for holding the processed transmitted context.
Preferably, the single memory includes a plurality of separate memories, at least one of the plurality of separate memories being external to the engine, and at least one of the plurality of separate memories being included within the engine.
There is further provided, according to a preferred embodiment of the present invention, a method for processing in an off-load engine a data packet conveyed between a target device and a network over a transport connection, the data packet including a payload and a header, including:
holding, in a payload buffer, data that is exchanged between the off-load engine, the network, and the target device for inclusion in the payload; processing context information with respect to the transport connection;; holding, in a context buffer, the context information; performing an arbitration, among payload requests to convey the data between the payload buffer and a single memory that stores both the data and the context information, and context requests to convey the context information between the context buffer and the single memory; and conveying the data in the payload buffer and the context information in the context buffer to and from the single memory responsive to the arbitration.
The method preferably includes at least one of the payload buffer, the packet processor, and the context buffer, generating at least one of the payload requests and the context requests responsive to receiving the data.
Preferably, the payload requests include a write-payload-to and a read-payload-from request to the single memory, and wherein the context requests include a write-context-to and a read-context-from request to the single memory.
Preferably, conveying the data and the context information includes multiplexing the data and the context information.
The method preferably also includes:
receiving the data packet from the network; stripping the header from the data packet so as to provide the data for holding in the payload buffer; and routing the payload to the target device responsive to the context information.
Preferably, the method further includes:
receiving the payload from the target device; generating the header responsive to the context information; appending the header to the payload to form the data packet; and transmitting the data packet to the network.
Preferably, the payload buffer includes at least one receiver payload buffer for holding the data responsive to receiving the data packet from the network and at least one transmitter payload buffer for holding the data responsive to transmitting the data packet to the network, processing the context information includes providing at least one receiver packet processor for processing the header together with the context information responsive to receiving the data packet from the network so as to generate processed received context, and providing at least one transmitter packet processor for processing the header together with the context information responsive to transmitting the data packet to the network so as to generate processed transmitted context, and the context buffer includes a receiver context buffer for holding the processed received context and a transmitter context buffer for holding the processed transmitted context.
Preferably, the single memory includes a plurality of separate memories, at least one of the plurality of separate memories is external to the engine, and at least one of the plurality of separate memories is included within the engine.
There is further provided, according to a preferred embodiment of the present invention, a method for processing a data packet having a payload in an off-load engine, the packet being conveyed over a transport connection through a network, the method including
receiving the payload; generating, responsive to receiving the payload, at least one of a plurality of read-write requests to a memory storing the payload of the packet and context information with respect to the connection; performing an arbitration between the plurality of read-write requests; conveying the at least one of the read-write requests to the memory responsive to the arbitration; and transferring the payload and the context information between the memory and the off-load engine responsive to an acceptance of the at least one of the read-write requests by the memory.
There is further provided, according to a preferred embodiment of the present invention, an off-load engine for processing a data packet having a payload, which is conveyed over a transport connection through a network, the engine including:
a packet processor which is adapted, responsive to receipt of the payload by the off-load engine, to generate at least one of a plurality of read-write requests to a memory storing the payload of the packet and context information with respect to the connection; and an arbiter which is adapted to perform an arbitration between the plurality of read-write requests and, responsive to the arbitration, to convey the at least one of the read-write requests to the memory and, responsive to the memory accepting the at least one of the read-write requests, to transfer the payload and the context information between the memory and the off-load engine.
The present invention will be more fully understood from the following detailed description of the preferred embodiments thereof, taken together with the drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic block diagram of a system illustrating an off-load engine and elements coupled to the engine, according to a preferred embodiment of the present invention;
FIG. 2 is a flowchart showing steps performed by the off-load engine of FIG. 1 when a packet is received from a network, according to a preferred embodiment of the present invention;
FIG. 3 is a flowchart showing steps performed by the off-load engine of FIG. 1 when a packet is transmitted into the network, according to a preferred embodiment of the present invention; and
FIG. 4 shows schematic graphs of transfer rates of data vs. packet length, according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Reference is now made to FIG. 1 , which is a schematic block diagram of a system 10 illustrating an off-load engine 12 and elements coupled to the engine, according to a preferred embodiment of the present invention. A target 16 is coupled to a data network 14 , and the target is able to transmit data to the network, and receive data from the network, in the form of packets. Preferably, network 14 comprises an Ethernet network, and the data transferred between target 16 and the network is in the form of Transmission Control Protocol (TCP) packets, the packets comprising a header and a payload. It will be appreciated, however, that the scope of the present invention is not limited to such TCP packets and/or Ethernet networks. Rather, the scope of the present invention comprises any packet having a payload and a header providing information as to disposition of the payload, and any network which is able to transmit and receive such packets.
Target 16 is coupled to network 14 via off-load engine 12 , herein also referred to as TCP off-load engine (ToE) 12 . ToE 12 acts as a network termination, and comprises a receiver section 28 and a transmitter section 30 . For a packet received from the network, receiver section 28 removes a header from the packet, and conveys a payload of the packet to target 16 according to a transport connection of the packet. For a packet transmitted to the network, transmitter section 30 receives the payload of the packet from target 16 , adds a header to the payload according to the connection, and transmits the packet so formed to network 14 .
In order to route the payload of the received packet to its correct destination, receiver section 28 uses context information associated with the packet, initial context information being generated at connection initialization from software running in ToE 12 or in target 16 . Context information for the packet comprises parameters associated with and describing a connection via which the packet is conveyed. Such parameters include, for example, a state of the connection, a flow control state, a sequence number of a last received segment/packet, and a pointer to a memory location of connection data. For each received packet, the context information is derived from the header of the packet and from previous context information for the connection which is accessed by ToE 12 .
For each transmitted packet, ToE 12 generates context information for the packet from previous context information for the packet's connection and from target 16 . ToE 12 uses the context information to construct a header for the payload, appends the header to the payload to form the packet, and then transmits the packet into network 14 .
ToE 12 comprises a request controller and arbiter 22 , herein termed arbiter 22 . Arbiter 22 acts as an arbiter of read-write requests received for an external memory 18 , and comprises a memory access multiplexer/demultiplexer 23 for payload data and context information transferred between the memory and ToE 12 . Arbiter 22 is coupled to an external memory interface 20 , receiver payload buffers 34 and 42 , a receiver context buffer 38 , transmitter payload buffers 33 and 41 , and a transmitter context buffer 37 . ToE 12 also comprises a memory 45 . The functions of these elements, as well as processing blocks comprised in receiver section 28 and transmitter section 30 , are described below, with reference to FIGS. 2 , 3 , and 4 . The coupling between elements of ToE 12 is by dedicated point-to-point busses.
FIG. 2 is a flowchart showing steps performed by ToE 12 when a packet is received from network 14 , according to a preferred embodiment of the present invention. In a first step 50 , network 14 transfers the packet to a receiver initial processing block 32 . The packet is stored in block 32 while the block performs initial processing on the packet, the initial processing comprising, inter alia, checks for errors in the packet by checking a cyclic redundancy code (CRC), and/or a TCP checksum, and/or an Internet Protocol (IP) address. The initial processing also preferably includes parsing of the packet to find the boundary between the payload and the header, and removing lower layers zero padding.
In addition, processing block 32 performs an initial “search” to find a local connection value corresponding to a connection to which the packet belongs. The local connection value enables block 32 to determine which context is to be loaded. Such searches are known in the art.
In a second step 52 , payload data of the packet is transferred to payload buffer 34 . In step 52 , read-write requests directed to external memory 18 are also sent to arbiter 22 . The requests comprise a write-payload request from payload buffer 34 , asking that external memory 18 receive the payload data in the buffer. A read-context request is also sent, preferably from buffer 34 , asking that the external memory provide context information, for the connection on which the packet has been transmitted, to context buffer 38 . Alternatively, the read-context request is sent from initial processing block 32 or further processing block 36 . The header of the packet, and/or processing control, is transferred to a receiver further processing block 36 .
In a third step 53 , arbiter 22 arbitrates between the write-payload request and the read-context request to memory 18 , and between other read-write requests to the memory described below. Arbiter 22 performs the arbitration according to pre-determined parameters such as an amount of data that will be conveyed responsive to each request, sizes of buffers used for each request, space available in the buffers, availability of the buffers, and a priority set for each request. After arbitration, arbiter 22 forwards the write-payload request and the read-context request to external memory 18 .
In a fourth step 54 , external memory 18 accepts the write-payload request, and the payload data is written to the external memory via multiplexer 23 and memory interface 20 . Also, responsive to the read-context request, the context information for the connection is read from external memory 18 to context buffer 38 via memory interface 20 and multiplexer 23 . Further processing block 36 uses the context available in buffer 38 to continue processing of the header, including, for example, performing TCP sequence number validation and out-of-order packet handling.
In a fifth step 56 , further processing block 36 updates the context information and transfers the updated context information to buffer 38 . Buffer 38 generates a write-context request, which is arbitrated and conveyed by arbiter 22 to external memory 18 . Responsive to the write-context request, the updated context is written to external memory 18 , replacing the context for the connection previously stored in the external memory. The header of the packet, and/or processing control, is transferred to a receiver output processing block 44 .
In a sixth step 58 , output processing block 44 generates a read-payload request, which is arbitrated and conveyed by arbiter 22 to external memory 18 . Responsive to the request, the payload data is read from external memory 18 and stored in payload buffer 42 . Output processing block 44 checks that target 16 is ready to accept the payload, and conveys the payload from buffer 42 according to the updated context in context buffer 38 . If one or more packets have been dropped while being transmitted in network 14 , step 58 is most preferably not implemented until the dropped packets have been re-transmitted by the far end of the connection, so that ToE 12 is able to convey payloads to target 16 in their correct order.
It will be appreciated that receiver processing blocks 32 , 36 , and 44 act as a receiver packet processor, and that the tasks performed by the blocks may be divided between the blocks in ways other than those described hereinabove, as will be understood by those skilled in the art. It will also be understood that the tasks performed by blocks 32 , 36 , and 44 are not limited to those described hereinabove, and that the blocks may perform other tasks, known in the art, for processing of received packets.
FIG. 3 is a flowchart showing steps performed by ToE 12 when a packet is transmitted into network 14 from target 16 , according to a preferred embodiment of the present invention. In a first step 70 , target 16 transfers a payload to be transmitted, and a header, to a transmitter initial processing block 31 . Block 31 performs a preliminary analysis of the header, and passes the header, and/or control, to a transmitter further processing block 35 . The preliminary analysis is generally similar, mutatis mutandis, to that performed by receiver block 32 , as described above. Block 31 also transfers the payload to transmitter payload buffer 33 .
In a second step 72 , buffer 33 sends a write-payload request to arbiter 22 , asking that external memory 18 receives payload data from the buffer. Further processing block 35 also sends a read-context request to the arbiter. The context request asks that previous context information stored in memory 18 , for the connection on which the payload is to be sent, is written to context buffer 37 .
In a third step 74 , arbiter 22 arbitrates between the write-payload request and the read-context request and between other requests. After arbitration, arbiter 22 forwards the write-payload request and the read-context request to external memory 18 .
In a fourth step 76 , external memory 18 accepts the write-payload request, and the payload data is written to the external memory via multiplexer 23 and memory interface 20 . Also, responsive to the read-context request, the context information for the connection is read from external memory 18 to context buffer 37 via memory interface 20 and multiplexer 23 .
In a fifth step 78 , further processing block 35 updates the context information in buffer 37 . The updated context information is generated from the context information already in buffer 37 and from header information supplied by initial processing block 31 . The updated context information is written to context buffer 37 , replacing the previous context information stored therein. Substantially as described above with reference to step 56 ( FIG. 2 ), the updated context is then stored in external memory 18 . Further processing block 35 also performs processes such as managing flow control towards the network and processing flow control messages from receiver section 28 . The header of the packet, and/or processing control, is transferred to a transmitter output processing block 43 .
In a sixth step 80 , output processing block 43 generates a read-payload request, which is arbitrated and conveyed by arbiter 22 to external memory 18 . Responsive to the request, the payload data is read from external memory 18 and stored in payload buffer 41 . Block 43 forms a header responsive to the context information in buffer 37 and to the header passed from block 35 . Block 43 attaches the header it forms to the payload in buffer 41 to form a packet, and transmits the packet to network 14 . As for step 58 , ( FIG. 2 ), a transmitted packet may not be automatically transmitted on receipt of data from target 16 . For example, transmission of the packet may be delayed until a remote receiver has indicated its readiness to receive the transmission.
It will be appreciated that transmitter processing blocks 31 , 35 , and 43 act as a transmitter packet processor, and that the tasks performed by the blocks may be divided between the blocks in ways other than those described hereinabove, as will be understood by those skilled in the art. It will also be understood that the tasks performed by blocks 31 , 35 , and 43 are not limited to those described hereinabove, and that the blocks may perform other tasks, known in the art, for processing of transmitted packets.
It will be appreciated that both for transmission and receiving of packets, writing to external memory 18 and reading from the external memory are, although related, not directly synchronized.
FIG. 4 shows schematic graphs of required transfer rates of data vs. packet length, according to a preferred embodiment of the present invention. The graph ordinate is the required bandwidth in bits/s; the graph abscissa is the length of a packet in bytes. The graphs of FIG. 4 are representative of rates of transfer of data to one or more memories used to store payload and context of packets. A graph 100 shows required bandwidth if only payload is transferred to the memories. A graph 102 shows required bandwidth if only context is transferred to the memories. A graph 104 is the sum of graphs 100 and 102 .
The graphs show values assuming that a line bandwidth, B, for writing to the memories is 10 Gbit/s, a packet may have a length L from 60 bytes to 1500 bytes, a header length, H, of each packet is 50 bytes, and a context transferred, C, for each packet is 80 bytes.
It will be understood that the graphs of FIG. 4 are by way of example, as are the values of B, L, H, and C.
A required bandwidth, P, for payload transfer, i.e., no header is written, is given by the expression:
P
=
B
·
L
-
H
L
(
1
)
Graph 100 plots equation (1). As is shown in the graph, the maximum value of P, 9.7 Gb/s, occurs for L=1500, corresponding to the case when all packets received have the largest possible packet length. The minimum value of P, for L=60, is 1.3 Gb/s.
A required bandwidth Q for context transfer to the memory is given by the expression:
Q
=
B
·
C
L
(
2
)
(Equations (1) and (2) assume the whole bandwidth B is filled by packets of length L, giving a packet rate
B
L
.
Graph 102 plots equation (2). As is shown in the graph, the maximum value of Q, 13.3 Gb/s, occurs for L=60, i.e., the smallest possible packet length. The minimum value of Q, when L=1500 bytes, is 0.5 Gb/s.
Graph 104 corresponds to a sum of graphs 102 and 104 , and corresponds to the required transfer rate if a single memory is used. Graph 104 has a largest value of 13.3+1.3=14.6 Gb/s (for L=60 bytes).
It will be understood that if two separate memories, a first for context and a second for payload had been used, a required total rate of transfer to the memories is 9.7+13.3=23 Gb/s. Thus, transferring to a single memory generates considerable savings of bandwidth.
It will thus be appreciated that multiplexing the context information and payload data is an efficient method for transferring context and payload between the ToE 12 and memory 18 . Furthermore, an overall efficiency of operation of ToE 12 may be further increased by altering priorities for the different types of read-write memory transfers (write-payload, read-payload, write-context, read-context) according to demand, such as by incorporating an adaptive system into arbiter 22 and/or by enabling the priorities to be set externally. It will also be understood that bandwidth is saved since headers are not written to memory 18 .
In some preferred embodiment of the present invention, at least a part of the context information may be written to memory 45 , so that the context is available within the off-load engine. It will be understood that respective parts of the context stored in memory 45 may be a selected part of the context for all the connections, or specific to respective connections on which packets are transmitted. Also, memory 45 may be implemented as one or more memory instances in ToE 12 . It will also be understood that external memory 18 may comprise more than one separate memory, each containing payload and context information. For example, a data packet receiver may have a first memory, and a data packet transmitter may have a second memory.
Furthermore, by using a single external memory, such as memory 18 , for storing both payload data and context information, off-load engine 12 is able to reduce numbers of pins required for connecting the memory and the engine, compared to off-load engines which use separate memories for storing context and payload, since only a single address bus is required.
It will be understood that the scope of the present invention may be applied for substantially any data packet having a header comprising information for disposition of a payload comprised in the packet. Such packets include, but are not limited to, Transport Control Protocol (TCP), Internet protocol (IP), and Internet Small Computer System Interface (iSCSI) packets.
It will thus be appreciated that the preferred embodiments described above are cited by way of example, and that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove, as well as variations and modifications thereof which would occur to persons skilled in the art upon reading the foregoing description and which are not disclosed in the prior art. | An off-load engine for processing a packet conveyed between a target and a network over a transport connection, the packet including a payload and a header. The engine includes a payload buffer, for holding data exchanged between the off-load engine, the network, and the target for inclusion in the payload, and a packet processor, for processing context of the transport connection.
The engine also includes a context buffer, for holding the context processed by the packet processor, a memory access multiplexer, which is coupled to convey the data in the payload buffer and the context in the context buffer to and from a memory that stores both the data and the context, and an arbiter, which controls the multiplexer by arbitrating among payload requests to convey the data between the payload buffer and the memory and context requests to convey the context between the context buffer and the memory. | 7 |
The present invention relates to wireless communications links and specifically to high data rate point-to-point links. This application is a continuation-in-part application of Ser. No. 09/847,629 filed May 2, 2001, Ser. No. 09/872,542 filed Jun. 2, 2001, Ser. No. 09/872,621 filed Jun. 2, 2001, Ser. No. 09/882,482 filed Jun. 14, 2001, Ser. No. 09/952,591, filed Sep. 14, 2001, Ser. No. 09/965,875 filed Sep. 28, 2001 Ser. No. 10/046,348 filed Oct. 25, 2001, Ser. No. 10/001,617 filed Oct. 30, 2001, Ser. No. 09/992,251 filed Nov. 13, 2001, Ser. No. 10/000,182 filed Dec. 1, 2001, Ser. No. 10/025,127, filed Dec. 18, 2001 and Ser. No. 10/041,083 filed Jan. 5, 2002, all of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
Wireless Communication Point-to-Point and Point-to-Multi-Point
Wireless communications links, using portions of the electromagnetic spectrum, are well known. Most such wireless communication at least in terms of data transmitted is one way, point to multi-point, which includes commercial radio and television. However there are many examples of point-to-point wireless communication. Mobile telephone systems that have recently become very popular are examples of low-data-rate, point-to-point communication. Microwave transmitters on telephone system trunk lines are another example of prior art, point-to-point wireless communication at much higher data rates. The prior art includes a few examples of point-to-point laser communication at infrared and visible wavelengths.
Need for High Volume Information Transmission
The need for faster (i.e., higher volume per unit time) information transmission is growing rapidly. Today and into the foreseeable future transmission of information is and will be digital with volume measured in bits per second. To transmit a typical telephone conversation digitally utilizes about 5,000 bits per second (5 Kbits per second). Typical personal computer modems connected to the Internet operate at, for example, 56 Kbits per second. Music can be transmitted point to point in real time with good quality using mp3 technology at digital data rates of 64 Kbits per second. Video can be transmitted in real time at data rates of about 5 million bits per second (5 Mbits per second). Broadcast quality video is typically at 45 or 90 Mbps. Companies (such as telephone and cable companies) providing point-to-point communication services build trunk lines to serve as parts of communication links for their point-to-point customers. These trunk lines typically carry hundreds or thousands of messages simultaneously using multiplexing techniques. Thus, high volume trunk lines must be able to transmit in the gigabit (billion bits, Gbits, per second) range. Most modem trunk lines utilize fiber optic lines. A typical fiber optic line can carry about 2 to 10 Gbits per second and many separate fibers can be included in a trunk line so that fiber optic trunk lines can be designed and constructed to carry any volume of information desired virtually without limit. However, the construction of fiber optic trunk lines is expensive (sometimes very expensive) and the design and the construction of these lines can often take many months especially if the route is over private property or produces environmental controversy. Often the expected revenue from the potential users of a particular trunk line under consideration does not justify the cost of the fiber optic trunk line. Digital microwave communication has been available since the mid-1970's. Service in the 18-23 GHz radio spectrum is called “short-haul microwave” providing point-to-point service operating between 2 and 7 miles and supporting between four to eight T 1 links (each at 1.544 Mbps). Recently, microwave systems operation in the 11 to 38 GHz band have reportedly been designed to transmit at rates up to 155 Mbps (which is a standard transmit frequency known as “OC-3 Standard”) using high order modulation schemes.
Data Rate vs. Frequency
Bandwidth-efficient modulation schemes allow, as a general rule, transmission of data at rates of 1 to 10 bits per Hz of available bandwidth in spectral ranges including radio wave lengths to microwave wavelengths. Data transmission requirements of 1 to tens of Gbps thus would require hundreds of MHz of available bandwidth for transmission. Equitable sharing of the frequency spectrum between radio, television, telephone, emergency services, military and other services typically limits specific frequency band allocations to about 10% fractional bandwidth (i.e., range of frequencies equal to about 10% of center frequency). AM radio, at almost 100% fractional bandwidth (550 to 1650 GHz) is an anomaly; FM radio, at 20% fractional bandwidth, is also atypical compared to more recent frequency allocations, which rarely exceed 10% fractional bandwidth.
Reliability Requirements
Reliability typically required for wireless data transmission is very high, consistent with that required for hardwired links including fiber optics. Typical specifications for error rates are less than one bit in ten billion (10 −10 bit-error rates), and link availability of 99.999% (5 minutes of down time per year). This necessitates all-weather link operability, in fog and snow, and at rain rates up to 100 mm/hour in many areas.
Weather Conditions
In conjunction with the above availability requirements, weather-related attenuation limits the useful range of wireless data transmission at all wavelengths shorter than the very long radio waves. Typical ranges in a heavy rainstorm for optical links (i.e., laser communication links) are 100 meters and for microwave links, 10,000 meters.
Atmospheric attenuation of electromagnetic radiation increases generally with frequency in the microwave and millimeter-wave bands. However, excitation of rotational transitions in oxygen and water vapor molecules absorbs radiation preferentially in bands near 60 and 118 GHz (oxygen) and near 23 and 183 GHz (water vapor). Rain, which attenuates through large-angle scattering, increases monotonically with frequency from 3 to nearly 200 GHz. At the higher, millimeter-wave frequencies, (i.e., 30 GHz to 300 GHz corresponding to wavelengths of 1.0 millimeter to 1.0 centimeter) where available bandwidth is highest, rain attenuation in very bad weather limits reliable wireless link performance to distances of 1 mile or less. At microwave frequencies near and below 10 GHz, link distances to 10 miles can be achieved even in heavy rain with high reliability, but the available bandwidth is much lower.
Need For Special Alignment Methods And Apparatus
High frequency, large antennas are typically designed to produce very narrow beams which must be very accurately aligned. Because of the narrow beams, both transmit and receive antennas must be precisely pointed at each other. Gimbals for these antennas are typically designed with two pointing angles; therefore, the process of aligning two antennas is essentially a 4 dimensional search. Since the antennas of the instant invention (such as a four-foot diameter antenna) can have narrow beams in the range of 0.15 degrees or less and are capable of thousands of discrete positions in each dimension, there are an extremely large number of four-dimensional alignments over which to search. As will be shown below, a complete search of this four-dimensional space could theoretically consume many years.
Therefore, what is needed are equipment and methods for aligning a wireless data link having very narrow beam widths and keeping them aligned.
SUMMARY OF THE INVENTION
The present invention provides equipment and methods for aligning the antennas of a point-to-point wireless millimeter wave communications link and keeping them aligned. Each of two communicating antennas is equipped with a telescopic camera connected to a processor programmed to recognize landscape images. The processors are programmed to remember the pattern of the landscape as it appears when the antennas are aligned. Each of the cameras then view the landscape periodically or continuously and if the landscape in view changes by more than a predetermined amount a signal is provided to indicate a misalignment. An operator can then take corrective action or alternatively the antenna system can be configured for remote or automatic realignment based of feedback from the camera. In a preferred embodiment, the antennas are initially aligned by substituting a narrow band oscillator power source for the signal transmitting electronics associated with a first antenna and a power detector is substituted for the signal receiving electronics of associated with a second antenna. In preferred embodiments after a first alignment procedure is performed, the procedure is repeated with an oscillator power source connected to the second antenna and a power detector connected to the first antenna. In other preferred embodiments the antennas are pre-aligned using a signaling mirror, a narrow beam searchlight, or laser. After the antennas are aligned the transceiver electronics are reconnected. In preferred embodiments the communication link operates within the 92 to 95 GHz portion of the millimeter spectrum and provides data transmission rates in excess of 155 Mbps. A first transceiver transmits at a first bandwidth and receives at a second bandwidth both within the above spectral range. A second transceiver transmits at the second bandwidth and receives at the first bandwidth. The transceivers are equipped with antennas providing beam divergence small enough to ensure efficient spatial and directional partitioning of the data channels so that an almost unlimited number of transceivers will be able to simultaneously use the same spectrum. Antennas and rigid support towers are described to maintain beam directional stability to less than one-half the half-power beam width. In a preferred embodiment the first and second spectral ranges are 92.3-93.2 GHz and 94.1-95.0 GHz and the half power beam width is about 0.15 degrees or less.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a millimeter-wave transmitter of a prototype transceiver system built and tested by Applicants.
FIG. 2 is a schematic diagram of a millimeter-wave receiver of a prototype transceiver system built and tested by Applicants.
FIG. 3 is measured receiver output voltage from the prototype transceiver at a transmitted bit rate of 200 Mbps.
FIG. 4 is the same waveform as FIG. 3, with the bit rate increased to 1.25 Gbps.
FIGS. 5A, 5 B 1 , and 5 B 2 are schematic diagrams of a millimeter-wave transmitter and receiver in one transceiver of a preferred embodiment of the present invention.
FIGS. 6A, 6 B 1 , and 6 B 2 are schematic diagrams of a millimeter-wave transmitter and receiver in a complementary transceiver of a preferred embodiment of the present invention.
FIGS. 7A and 7B show the spectral diagrams for a preferred embodiment of the present invention.
FIG. 8 is a layout showing an installation using a preferred embodiment of the present invention.
FIGS. 9 and 9A show a preferred hollow steel tube antenna support structure (diameter of 24 inches) rigid enough for use in a preferred embodiment of the present invention.
FIG. 10 shows how very slight directional instability can interfere with transmission.
FIG. 11 shows how narrow a beam is when produced by a diffraction-limited 4-foot diameter antenna operating at 94 GHz.
FIGS. 12A and 12B diagrammatically show how a signaling device is used to aid in the preliminary alignment of the telecommunications link.
FIG. 13 is a schematic of an alignment system comprising a Gunn oscillator power source and a power detector.
FIG. 14 is a schematic of the millimeter-wave power detector.
FIGS. 15A and 15B illustrate the positions of a power source and a power detector relative to the first and second antennas during the fine alignment procedures.
FIG. 16 shows an alignment assurance camera mounted to a sighting telescope mounted to an antenna operating at millimeter wave frequencies.
FIG. 17 shows a scene as observed from the position of the alignment assurance camera location.
FIGS. 18A and 18B show two images of a magnified portion of the scene of FIG. 13 at different times (before and after the antenna has suffered an alignment shift).
FIG. 19 is a schematic diagram of an out-of-band signaling system for communicating antenna alignment information to a NOC.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Prototype Demonstration
A prototype demonstration of the millimeter-wave transmitter and receiver useful for the present invention is described by reference to FIGS. 1 to 4 . With this embodiment the Applicants have demonstrated digital data transmission in the 93 to 97 GHz range at 1.25 Gbps with a bit error rate below 10 −12 .
The circuit diagram for the millimeter-wave transmitter is shown in FIG. 1 . Voltage-controlled microwave oscillator 1 , Westec Model VTS133/V4, is tuned to transmit at 10 GHz, attenuated by 16 dB with coaxial attenuators 2 and 3 , and divided into two channels in two-way power divider 4 . A digital modulation signal is pre-amplified in amplifier 7 , and mixed with the microwave source power in triple-balanced mixer 5 , Pacific Microwave Model M3001HA. The modulated source power is combined with the un-modulated source power through a two-way power combiner 6 . A line stretcher 12 in the path of the un-modulated source power controls the depth of modulation of the combined output by adjusting for constructive or destructive phase summation. The amplitude-modulated 10 GHz signal is mixed with a signal from a 85-GHz source oscillator 8 in mixer 9 and high-pass filtered in waveguide filter 13 to reject the 75 GHz image band. The resultant, amplitude-modulated 95 GHz signal contains spectral components between 93 and 97 GHz, assuming unfiltered 1.25 Gbps modulation. A rectangular WR- 10 wave guide output of the high pass filter is converted to a circular wave guide 14 and fed to a circular horn 15 of 4 inches diameter, where it is transmitted into free space. The horn projects a half-power beam width of 2.2 degrees.
The circuit diagram for the receiver is shown in FIG. 2 . The antenna is a circular horn 15 R of 6 inches in diameter, fed from a waveguide unit 14 R consisting of a circular W-band wave-guide and a circular-to-rectangular wave-guide converter which translates the antenna feed to WR- 10 wave-guide which in turn feeds heterodyne receiver module 2 R. This module consists of a monolithic millimeter-wave integrated circuit (MMIC) low-noise amplifier spanning 89-99 GHz, a mixer with a two-times frequency multiplier at the LO port, and an IF amplifier covering 5-15 GHz. These receivers are available from suppliers such as Lockheed Martin. The local oscillator 8 R is a cavity-tuned Gunn oscillator operating at 42.0 GHz (Spacek Model GQ410K), feeding the mixer in module R 2 through a 6 dB attenuator 7 . A bias tee 6 R at the local oscillator input supplies DC power to receiver module 2 R. A voltage regulator circuit using a National Semiconductor LM317 integrated circuit regulator supplies +3.3V through bias tee 6 R. An IF output of the heterodyne receiver module 2 R is filtered at 6-12 GHz using bandpass filter 3 R from K&L Microwave. Receiver 4 R that is an HP Herotek Model DTM 180AA diode detector, measures total received power. The voltage output from the diode detector is amplified in two-cascaded microwave amplifiers 5 R from MiniCircuits, Model 2FL2000. The baseband output is carried on coax cable to a media converter for conversion to optical fiber, or to a Bit Error-Rate Tester (BERT) 10 R.
In the laboratory, this embodiment has demonstrated a bit-error rate of less than 10 −12 for digital data transmission at 1.25 Gbps. The BERT measurement unit was a Microwave Logic, Model gigaBERT. The oscilloscope signal for digital data received at 200 Mbps is shown in FIG. 3 . At 1.25 Gbps, oscilloscope bandwidth limitations lead to the rounded bit edges seen in FIG. 4 . Digital levels sustained for more than one bit period comprise lower fundamental frequency components (less than 312 MHz) than those which toggle each period (622 MHz), so the modulation transfer function of the oscilloscope, which falls off above 500 MHz, attenuates them less. These measurement artifacts are not reflected in the bit error-rate measurements, which yield <10 −12 bit error rate at 1.25 Gbps.
Transceiver System
A preferred embodiment of the present invention is described by reference to FIGS. 5 to 7 . The link hardware consists of a millimeter-wave transceiver pair including a pair of millimeter-wave antennas and a microwave transceiver pair including a pair of microwave antennas. The millimeter wave transmitter signal is amplitude modulated and single-sideband filtered, and includes a reduced-level carrier. The receiver includes a heterodyne mixer, phase-locked intermediate frequency (IF) tuner, and IF power detector.
Millimeter-wave transceiver A (FIGS. 5A, 5 B 1 , and 5 B 2 ) transmits at 92.3-93.2 GHz as shown at 60 in FIG. 7 A and receives at 94.1-95.0 GHz as shown at 62 , while millimeter-wave transmitter B (FIGS. 6A, 6 B 1 , 6 B 2 ) transmits at 94.1-95.0 GHz as shown at 64 in FIG. 7 B and receives at 92.3-93.2 GHz as shown at 66 .
Millimeter Wave Transceiver A
As shown in FIG. 5A in millimeter-wave transceiver A, transmit power is generated with a cavity-tuned Gunn diode 21 resonating at 93.15 GHz. This power is amplitude modulated using two balanced mixers in an image reject configuration 22 , selecting the lower sideband only. The source 21 is modulated at 1.25 Gbps in conjunction with Gigabit-Ethernet standards. The modulating signal is brought in on optical fiber, converted to an electrical signal in media converter 19 (which in this case is an Agilent model HFCT-5912E) and amplified in preamplifier 20 . The amplitude-modulated source is filtered in a 900 MHz-wide passband between 92.3 and 93.2 GHz, using a bandpass filter 23 on microstrip. A portion of the source oscillator signal is picked off with coupler 38 and combined with the lower sideband in power combiner 39 , resulting in the transmitted spectrum shown at 60 in FIG. 7 A. The combined signal propagates with horizontal polarization through a waveguide 24 to one port of an orthomode transducer 25 , and on to a four-foot diameter Cassegrain dish antenna 26 , where it is transmitted into free space with horizontal polarization.
The receiver unit at Station A as shown on FIGS. 5 B 1 and 5 B 2 is fed from the same Cassegrain antenna 26 as is used by the transmitter, at vertical polarization (orthogonal to that of the transmitter), through the other port of the orthomode transducer 25 . The received signal is pre-filtered with bandpass filter 28 A in a passband from 94.1 to 95.0 GHz, to reject back scattered return from the local transmitter. The filtered signal is then amplified with a monolithic MMW integrated-circuit amplifier 29 on indium phosphide, and filtered again in the same passband with bandpass filter 28 B. This twice filtered signal is mixed with the transmitter source oscillator 21 using a heterodyne mixer-downconverter 30 , to an IF frequency of 1.00-1.85 GHz, giving the spectrum shown at 39 A in FIG. 7A. A portion of the IF signal, picked off with coupler 40 , is detected with integrating power detector 35 and fed to an automatic gain control circuit 36 . The fixed-level IF output is passed to the next stage as shown in FIG. 5 B 2 . Here a quadrature-based (I/Q) phase-locked synchronous detector circuit 31 is incorporated, locking on the carrier frequency of the remote source oscillator. The loop is controlled with a microprocessor 32 to minimize power in the “Q” channel while verifying power above a set threshold in the “I” channel. Both “I” and “Q” channels are lowpass-filtered at 200 MHz using lowpass filters 33 A and 33 B, and power is measured in both the “I” and “Q” channels using square-law diode detectors 34 . The baseband mixer 38 output is pre-amplified and fed through a media converter 37 , which modulates a laser diode source into a fiber-optic coupler for transition to optical fiber transmission media.
Transceiver B
As shown in FIG. 6A in millimeter-wave transceiver B, transmit power is generated with a cavity-tuned Gunn diode 41 resonating at 94.15 GHz. This power is amplitude modulated using two balanced mixers in an image reject configuration 42 , selecting the upper sideband only. The source 41 is modulated at 1.25 Gbps in conjunction with Gigabit-Ethernet standards. The modulating signal is brought in on optical fiber as shown at 80 , converted to an electrical signal in media converter 60 , and amplified in preamplifier 61 . The amplitude-modulated source is filtered in a 900 MHz-wide passband between 94.1 and 95.0 GHz, using a bandpass filter 43 on microstrip. A portion of the source oscillator signal is picked off with coupler 48 and combined with the higher sideband in power combiner 49 , resulting in the transmitted spectrum shown at 64 in FIG. 7 B. The combined signal propagates with vertical polarization through a waveguide 44 to one port of an orthomode transducer 45 , and on to a four-foot Cassegrain dish antenna 46 , where it is transmitted into free space with vertical polarization.
The receiver is fed from the same Cassegrain antenna 46 (FIG. 6 B 1 ) as the transmitter, at horizontal polarization (orthogonal to that of the transmitter), through the other port of the orthomode transducer 45 . The received signal is filtered with bandpass filter 47 A in a passband from 92.3 to 93.2 GHz, to reject backscattered return from the local transmitter. The filtered signal is then amplified with a monolithic MMW integrated-circuit amplifier on indium phosphide 48 , and filtered again in the same passband with bandpass filter 47 B. This twice filtered signal is mixed with the transmitter source oscillator 41 using a heterodyne mixer-downconverter 50 , to an IF frequency of 1.00-1.85 GHz, giving the spectrum shown at 39 B in FIG. 7B. A portion of the IF signal, picked off with coupler 62 , is detected with integrating power detector 55 and fed to an automatic gain control circuit 56 . The fixed-level IF output is passed to the next stage as shown on FIG. 6 B 2 . Here a quadrature-based (I/Q) phase-locked synchronous detector circuit 51 is incorporated, locking on the carrier frequency of the remote source oscillator. The loop is controlled with a microprocessor 52 to minimize power in the “Q” channel while verifying power above a set threshold in the “I” channel. Both “I” and “Q” channels are lowpass-filtered at 200 MHz using a bandpass filters 53 A and 53 B, and power is measured in each channel using a square-law diode detector 54 . The baseband mixer 58 output is pre-amplified and fed through a media converter 57 , which modulates a laser diode source into a fiber-optic coupler for transition to optical fiber transmission media.
Very Narrow Beam Width
A dish antenna of four-foot diameter projects a half-power beam width of about 0.15 degrees at 94 GHz. The full-power beamwidth (to first nulls in antenna pattern) is narrower than 0.45 degrees. This suggests that about 800 independent beams could be projected azimuthally around an equator from a single transmitter location, without mutual interference, from an array of 4-foot dishes. At a distance of ten miles, two receivers placed 400 feet apart can receive independent data channels from the same transmitter location. Conversely, two receivers in a single location can discriminate independent data channels from two transmitters ten miles away, even when the transmitters are as close as 400 feet apart. Larger dishes can be used for even more directivity.
Rigid Antenna Support
A communication beam having a half-power beam width of only about 0.15 degrees requires an extremely stable antenna support. Prior art antenna towers such as those used for microwave communication typically are designed for angular stability of about 0.6 to 1.1 degrees or more. Therefore, the present invention requires much better control of beam direction. For good performance the receiving antenna should be located at all times within the half power foot print of the transmitted beam. At 10 miles the half power footprint of a 0.15-degree beam is about 150 feet. During initial alignment the beam should be directed so that the receiving transceiver antenna is located approximately at the center of the half-power beam width footprint area. The support for the transmitter antenna should be rigid enough so that the beam direction does not change enough so that the receiving transceiver antenna is outside the half-power footprint. Thus, in this example the transmitting antenna should be directionally stable to within +/−0.09 degrees.
This rigid support of the antenna not only assures continued communication between the two transceivers as designed but the narrow beam widths and rigid antenna support reduces the possibility of interference with any nearby links operating in the same spectral band. Many rigid supports can be used for maintaining antenna alignment. Applicants have performed computer model studies of potential supports using WindCalculator software provided by Andrew Corp. with offices in St. Orland Park, Ill. and tower bending software know as Beam Calc.xls developed by WarrenDesignVision Company. For example, these calculations show that a solidly mounted 12-inch diameter 40 feet tall hollow carbon steel (one-half inch wall thickness) monopole tower having a 0.7 meter high, 1 meter diameter radome at the top (a two-foot diameter antenna is enclosed in the radome) would suffer deflections of about 0.74 degrees in a 90 mile per hour steady wind. FIG. 10 shows the effect of a 0.74-degree deflection of a 0.36-degree beam. The 0.74 degree deflection moves the beam axis 682 feet at 10 miles so that the receive antenna is clearly outside the beam 332 foot half power footprint. This angular variation would almost certainly disrupt communication between the millimeter wave links described above. However, similar calculations made for a solidly mounted 24-inch diameter, 40 feet tall hollow carbon steel monopole tower shows that the deflection in a 90 mile per hour wind would be only 0.11 degrees. This structure is shown in FIG. 9 . The 24-inch tube 700 supports radome 720 enclosing antenna 740 , antenna mount 760 and transceiver 750 (FIG. 9 A). Flange 710 is welded to the bottom of tube 700 and is bolted with bolts 800 encased in reinforced concrete base 820 which is buried mostly below ground level 730 . This would assure with substantial margin that the communication between the two transceivers would not be disrupted due to beam directional deviations. Therefore, in preferred embodiments, antennas of about 2 feet diameter are mounted on solidly mounted reinforced concrete monopole towers having heights of 40 feet or less as shown in FIG. 9 . The reader should note that many other potential rigid structures could be designed to support the antennas with the directional stability required under the general guidelines outlined above. For example, antennas could be rigidly mounted on the side or top of stable buildings. Steel trussed towers could be used or monopoles with high tension guide wires. In each case however the designer should determine using reliable codes or actual testing that these alternate supports are adequate to maintain the needed directional stability.
It is also possible to take care of directional stability using active antenna directional control with a feedback control system. However, such a system although feasible will typically be much more expensive than the rigid supports of the type described above.
Backup Microwave Transceiver Pair
During severe weather conditions data transmission quality will deteriorate at millimeter wave frequencies. Therefore, in preferred embodiments of the present invention a backup communication link is provided which automatically goes into action whenever a predetermined drop-off in quality transmission is detected. A preferred backup system is a microwave transceiver pair operating in the 10.7-11.7 GHz band. This frequency band is already allocated by the FCC for fixed point-to-point operation. FCC service rules parcel the band into channels of 40-MHz maximum bandwidth, limiting the maximum data rate for digital transmissions to 45 Mbps full duplex. Transceivers offering this data rate within this band are available off-the-shelf from vendors such as Western Multiplex Corporation (Models Lynx DS-3, Tsunami 100BaseT), and DMC Stratex Networks (Model DXR700 and Altium 155). The digital radios are licensed under FCC Part 101 regulations. The microwave antennas are Cassegrain dish antennas of 24-inch diameter. At this diameter, the half-power beamwidth of the dish antenna is 3.0 degrees, and the full-power beamwidth is 7.4 degrees, so the risk of interference is higher than for MMW antennas. To compensate this, the FCC allocates twelve separate transmit and twelve separate receive channels for spectrum coordination within the 10.7-11.7 GHz band.
Sensing of a millimeter wave link failure and switching to redundant microwave channel is an existing automated feature of the network routing switching hardware available off-the-shelf from vendors such as Cisco, Foundry Networks and Juniper Networks.
Narrow Beam Width Antennas
The narrow antenna beam widths afforded at millimeter-wave frequencies allow for geographical portioning of the airwaves, which is impossible at lower frequencies. This fact eliminates the need for band parceling (frequency sharing), and so enables wireless communications over a much larger bandwidth, and thus at much higher data rates, than were ever previously possible at lower RF frequencies.
The ability to manufacture and deploy antennas with beam widths narrow enough to ensure non-interference, requires mechanical tolerances, pointing accuracies, and electronic beam steering/tracking capabilities, which exceed the capabilities of the prior art in communications antennas. A preferred antenna for long-range communication at frequencies above 70 GHz has gain in excess of 50 dB, 100 times higher than direct-broadcast satellite dishes for the home, and 30 times higher than high-resolution weather radar antennas on aircraft. However, where interference is not a potential problem, antennas with dB gains of 40 to 45 may be preferred.
Most antennas used for high-gain applications utilize a large parabolic primary collector in one of a variety of geometries. The prime-focus antenna places the receiver directly at the focus of the parabola. The Cassegrainian antenna places a convex hyperboloidal secondary reflector in front of the focus to reflect the focus back through an aperture in the primary to allow mounting the receiver behind the dish. (This is convenient since the dish is typically supported from behind as well.) The Gregorian antenna is similar to the Cassegrainian antenna, except that the secondary mirror is a concave ellipsoid placed in back of the parabola's focus. An offset parabola rotates the focus away from the center of the dish for less aperture blockage and improved mounting geometry. Cassegrainian, prime focus, and offset parabolic antennas are the preferred dish geometries for the MMW communication system.
A preferred primary dish reflector is a conductive parabola. The preferred surface tolerance on the dish is about 15 thousandths of an inch (15 mils) for applications below 40 GHz, but closer to 5 mils for use at 94 GHz. Typical hydroformed aluminum dishes give 15-mil surface tolerances, although double-skinned laminates (using two aluminum layers surrounding a spacer layer) could improve this to 5 mils. The secondary reflector in the Cassegrainian geometry is a small, machined aluminum “lollipop” which can be made to 1-mil tolerance without difficulty. Mounts for secondary reflectors and receiver waveguide horns preferably comprise mechanical fine-tuning adjustment for in-situ alignment on an antenna test range.
Flat Panel Antenna
Another preferred antenna for long-range MMW communication is a flat-panel slot array antenna such as that described by one of the present inventors and others in U.S. Pat. No. 6,037,908, issued Mar. 14, 2000 which is hereby incorporated herein by reference. That antenna is a planar phased array antenna propagating a traveling wave through the radiating aperture in a transverse electromagnetic (TEM) mode. A communications antenna would comprise a variant of that antenna incorporating the planar phased array, but eliminating the frequency-scanning characteristics of the antenna in the prior art by adding a hybrid traveling-wave/corporate feed. Flat plates holding a 5-mil surface tolerance are substantially cheaper and easier to fabricate than parabolic surfaces. Planar slot arrays utilize circuit-board processing techniques (e.g., photolithography), which are inherently very precise, rather than expensive high-precision machining.
Coarse and Fine Pointing
Pointing a high-gain antenna requires coarse and fine positioning. Coarse positioning can be accomplished initially using a visual sight such as a bore-sighted rifle scope or laser pointer. The antenna is locked in its final coarse position prior to fine-tuning. The fine adjustment is performed with the remote transmitter turned on. A power meter connected to the receiver is monitored for maximum power as the fine positioner is adjusted and locked down.
At gain levels above 50 dB, wind loading and tower or building flexure can cause an unacceptable level of beam wander. A flimsy antenna mount could not only result in loss of service to a wireless customer; it could inadvertently cause interference with other licensed beam paths. In order to maintain transmission only within a specific “pipe,” some method for electronic beam steering may be required.
Beam Steering
Phased-array beam combining from several ports in the flat-panel phased array could steer the beam over many antenna beam widths without mechanically rotating the antenna itself. Sum-and-difference phase combining in a mono-pulse receiver configuration locates and locks on the proper “pipe.” In a Cassegrainian antenna, a rotating, slightly unbalanced secondary (“conical scan”) could mechanically steer the beam without moving the large primary dish. For prime focus and offset parabolas, a multi-aperture (e.g., quad-cell) floating focus could be used with a selectable switching array. In these dish architectures, beam tracking is based upon maximizing signal power into the receiver. In all cases, the common aperture for the receiver and transmitter ensures that the transmitter, as well as the receiver, is correctly pointed.
Typical Installation
FIG. 8 is a map layout of a proposed application of the present invention. This map depicts a sparsely populated section of the island, Maui in Hawaii. Shown are communication facility 70 which is connected to a major communication trunk line from a communication company's central office 71 , a technology park 72 located about 2 miles from facility 70 , a relay station 76 located about 6 miles from facility 70 and four large ocean-front hotels 78 located about 3 miles from relay station 76 . Also shown is a mountaintop observatory 80 located 13 miles from facility 70 and a radio antenna tower 79 located 10 miles from facility 70 . As indicated in FIG. 8, the angular separation between the radio antenna and the relay station is only 4.7 degrees. Four type-A transceiver units are positioned at facility 70 , each comprising a transmitter and receiver unit as described in FIGS. 5A and 5B. These units are directed at corresponding type-B transceiver units positioned at the technology park, the relay station, the observatory, and the radio tower. Millimeter wave transceiver units with back-up microwave units as described above are also located at the hotels and are in communication with corresponding units at the relay station. In a preferred embodiment the 1.25 GHz spectrum is divided among the four hotels so that only one link needs to be provided between facility 70 and relay station 76 . This system can be installed and operating within a period of about one month and providing the most modern communication links to these relatively isolated facilities. The cost of the system is a very small fraction of the cost of providing fiber optic links offering similar service.
The microwave backup links operate at approximately eight times lower frequency (8 times longer wavelength) than the millimeter wave link. Thus, at a given size, the microwave antennas have broader beam widths than the millimeter-wave antennas, again wider by about 8 times. A typical beam width from a 2-foot antenna is about 7.5 degrees. This angle is wider than the angular separation of four service customers (hotels) from the relay tower and it is wider than the angular separation of the beam between the relay station and the radio antenna. Specifically, the minimum angular separation between hotels from the relay station is 1.9 degrees. The angular separation between receivers at radio antenna tower 79 and relay station 76 is 4.7 degrees as seen from a transmitter at facility 70 . Thus, these microwave beams cannot be separated spatially; however, the FCC Part 101 licensing rules mandate the use of twelve separate transmit and twelve separate receive channels within the microwave 10.7 to 11.7 GHz band, so these microwave beams can be separated spectrally. Thus, the FCC sponsored frequency coordination between the links to individual hotels and between the links to the relay station and the radio antenna will guarantee non-interference, but at a much reduced data rate. The FCC has appointed a Band Manager, who oversees the combined spatial and frequency coordination during the licensing process.
FIG. 11 shows how narrow a beam is when produced by a diffraction-limited 4 foot diameter antenna operating at 94 GHz. An 8-degree by 8-degree field of view is indicated by the surrounding square 170 . The tiny circles, which are less than 0.15 degrees in diameter correspond to the full-width, half-maximum power beam-width produced by a diffraction-limited 4 foot diameter antenna operating at 94 GHz i.e. 94 GHz beam-width 174 . For comparison, the larger circles 178 (a little larger than 2 degrees) indicate the full-width, half-maximum power beam-width produced by a diffraction-limited 4-foot diameter antenna operating at 5.8 GHz. The corresponding FWHM footprint of a 0.15-degree beam is 40 meters (140 feet) at sixteen kilometers (ten miles) compared to a footprint of 560 meters (1800 feet) at ten miles for a 2-degree beam. Thus, it is apparent that the alignment search for a 5.8 GHz beam can be straightforward whereas the alignment search for a 94 GHz beam having the same size antenna can be much more difficult.
To establish a link requires two antennas (both with narrow beams) to be precisely pointing toward each other. In other words, the process of aligning a link is actually a 4-dimensional alignment (azimuth and elevation angles on antenna one and azimuth and elevation angles on antenna two).
A simple method of establishing such a co-alignment is to use the signal from one antenna as an alignment aid for its companion antenna. With relatively broad beams, such as a 5.8 GHz beams, this simple method of co-alignment can work. However, this simple method does not work well when applied to narrow millimeter wave beams emanating from large aperture antennas. One major problem with aligning two very narrow beam antennas is that one of the antennas has to be approximately aligned first before the second antenna can use the first antenna's signal as an alignment aid.
The simple method of co-alignment could be made to work by brut force of an exhaustive 4 dimensional search but this would typically consume valuable installation time and require expensive mounts (capable of 0.1 degree precise and repeatable positioning of large and heavy antennas) for both antennas. Assuming that each beam pointing step could be made and the antenna tightened into position in one minute, then the amount of time required to check each position within the four dimensional 8×8 degree window (8 degree by 8 degree for antenna one and 8 degree by 8 degree for antenna two) would be of the order of 8 million minutes; i.e., (8/0.15) 4 minutes or 15 years. Even if the process were automated with expensive and precise motor driven antenna mounts so that each pointing step could be accomplished in just one second, then the complete search time would still be too long to be practical (8 million seconds or 3 months).
Pre-Alignment
FIGS. 12A and 12B diagrammatically show how a signaling device is used to aid in the preliminary alignment of the telecommunications link. FIG. 12A shows a first installer 220 near a first antenna 222 (e.g., corresponding to location 70 of FIG. 8) holding a first rescue signaling mirror 224 available from Outback Gear, Niles, Ohio, an example of a signaling device. First rescue signaling mirror 224 reflects sunlight 229 toward second antenna 232 (e.g., corresponding to location 76 of FIG. 8 ). Second installer 230 looks through a second sighting scope 238 that has been previously aligned with the beam axis of second antenna 232 . Second installer 230 adjusts second mount 235 of second antenna 232 to point second sighting scope 238 , and thereby also second antenna 232 , toward first rescue signaling mirror 224 . These little mirrors (about 2 inches by 3 inches) produce narrow beams (but with relatively large footprints at a distances of 10 miles), and the installers can scan the beams so the reflected sun light covers a large enough range to easily encompass the opposite antenna location. The signaling mirror's output is easily distinguishable against the background light because the beam's brightness is essentially equal to the sun's brightness (though the signaling mirror's angular extent is much smaller).
A similar procedure is then followed except that the roles of the first installer (and associated equipment) are swapped with the second installer (and associated equipment). FIG. 12B shows second installer 230 near second antenna 232 holding a second rescue signaling mirror 234 . Second rescue signaling mirror 234 reflects sunlight 239 toward first antenna 222 . First installer 220 looks through a first sighting scope 228 that has been previously aligned with the beam axis of first antenna 222 . First installer 220 adjusts a first mount 225 of first antenna 222 to point first sighting scope 228 , and thereby also first antenna 222 , toward second rescue signaling mirror 234 .
After pre-alignment with signaling mirrors has been performed, the antennas are aligned to within about 1 degree or better. With such an optical pre-alignment a large reduction in the alignment search space has been accomplished. Instead of an 8 degree by 8 degree (for antenna one) by 8 degree by 8 degree (for antenna two) 15 year search, the problem is reduced to a 4-dimensional 1 degree search. In other words, the search space has been reduced by a factor of 8 4 (4096). (An alternative to the reflecting mirror, pre-alignment can also be accomplished using a narrow beam light source such as a searchlight or laser. In this case it may be desirable to do the pre-alignment in the early evening or at night.
With a 1-degree alignment for a 4-foot wide 94 GHz antenna system, communication may be possible with this imprecise alignment but both antennas would be receiving and sending via each other's side lobes. Depending on the aperture illumination functions for the antennas, the first side lobes will contain 13 dB to 40 dB less power than the primary beam (the smaller diminution corresponds to a uniformly illuminated aperture while the greater reduction corresponds to a very tapered illumination). To make matters even more challenging, it is likely that the antennas are not even looking at each other's first side lobe, but rather at a second, third or still higher order side lobe. Thus the amount of power transferred between two antennas pre-aligned to a seemingly accurate 1-degree level of precision, is likely several orders of magnitude smaller than for a well-aligned pair.
Precise Alignment with Gunn Oscillator
For more precise alignment Applicants prefer to use the alignment system illustrated in FIGS. 13 through 15B. FIG. 13 is a simplified schematic of an alignment system comprising a Gunn oscillator power source 310 and a millimeter-wave power detector 320 . For the alignment, Gunn oscillator power source 310 and millimeter-wave power detector 320 replace the radio transceiver pairs illustrated in FIGS. 5 and 6 during the alignment procedure. Gunn oscillator power source 310 and millimeter-wave power detector 320 are attached to antennas 26 and 46 as shown in FIG. 13 . By comparison with the radios that the power source and the power detector replace, the later are much more sensitive and have much greater dynamic range.
The Gunn oscillator 310 uses a gallium arsenide diode as its millimeter-wave power source and is available, for example, from Spacek Labs Santa Barbara, Calif. The Gunn oscillator 310 benefits by a factor of 2 in power (3 dB) on average compared to a radio by virtue of the fact that it is always turned on. The Gunn oscillator benefits by a factor of 5 in power (7 dB) compared to a radio because the Gunn oscillator does not have to suffer the conversion loss of the modulator. Hence, the Gunn oscillator can contribute about a factor of 10 (10 dB) improvement in sensitivity relative to radio sets.
The millimeter-wave power detector provides another resource for increasing sensitivity. FIG. 14 is a schematic of the millimeter-wave power detector. A first low noise amplifier (LNA) 410 , available, for example, from HRL Malibu, Calif., amplifies a signal received by antenna 46 (FIG. 13) then sends the amplified signal to a bandpass filter 420 , with about 1 GHz bandwidth (centered at millimeter-wave frequency of the Gunn oscillator 310 ) available, for example, from Quinstar Torrance, Calif. After filtering the signal is again amplified by a second LNA 430 , available, for example, from HRL Malibu, Calif. The twice amplified and once filtered signal is then converted by detector diode and integrating capacitor 440 to a voltage that is proportional to the original millimeter-wave signal power detected with a detector diode, available, for example as Model HP 9161, from Hewlett-Packard Santa Rosa, Calif. A post detection “integrating” capacitor is used which can result in overall bandwidth as narrow as 10 MHz or even as narrow as 1 kHz. Here the improvement stems from the ability to narrow the bandwidth (and hence noise power) of the detector. This is possible since we are only interested in detecting and measuring power in the case of aligning a link as contrasted with the requirements that prevail when sending data at extraordinarily high data rates. Thus, instead of needing 1 GHz or more of bandwidth (for high speed data transmission), it is possible to use only 10 MHz or less (during alignment) which narrows the band by a factor of greater than 100 and results in an improvement, which scales as the square-root of the bandwidth, by a factor of 10 (10 dB) or more.
By combining both of the above described alignment aids it is therefore possible to increase the sensitivity and dynamic range of a link by a factor of 100 (20 dB) during the alignment procedure.
An additional aid provided by the alignment system of FIG. 13 is the audio output device 330 that allows hands-free and eyes-free adjustments to a given antenna while the installer listens for improvements in the link alignment. A voltage proportional to the detected power level is generated in the millimeter wave detector 320 and sent to the voltage controlled oscillator (VCO) 332 . The oscillating output of VCO 332 is amplified by amplifier 334 then converted from electrical signal to auditory signal by speaker 336 . In addition to the auditory feedback for the installer, FIG. 13 shows a visual feedback by means of the voltage meter 340 . The voltage meter 340 is useful for making comparison of power over relatively longer time frames, say minutes or longer, while the audio output device 330 is more useful for making comparisons of power over relatively shorter time frames such a few seconds or less. Therefore, both methods of feedback are useful and desirable.
FIGS. 15A and 15B describe a preferred alignment method. FIG. 15A illustrates the positions of a power source A 510 and a power detector A 520 relative to first antenna 26 and second antenna 46 during the fine alignment procedure for the second antenna 46 . A first installer 517 turns on power source A 510 . The emitted power is directed toward second antenna 46 as a result of the prior preliminary alignment that was performed with the aid of signaling mirrors. A second installer 527 monitors the power detected by power detector A 520 while making small angular perturbations on the second antenna. Due to the prior preliminary alignment of both antennas, and the enhanced sensitivity of the alignment aids, the power detector A 520 is assured of receiving sufficient signal immediately upon initiating this fine alignment procedure. In other words, the second installer does not need to do any angular scan searching to acquire the signal. It is instantly on. The acquired signal has sufficient strength to be readily distinguished from background noise.
Second installer 527 continues to monitor the power detected by power detector A 520 while using small angular perturbations on the second antenna 46 to increase the strength of the received signal. Angular perturbations are continued along one axis until a maximum received signal is found. Then angular perturbations are performed along the other axis until a new, and larger, maximum received signal is found. This procedure is repeated, alternating between the two axes until a global maximum is found which corresponds to the best alignment orientation for second antenna 46 .
Once the orientation has been optimized for second antenna 46 it is time for aligning first antenna 26 . FIG. 15B illustrates the positions of a power source B 560 and a power detector B 570 relative to first antenna 26 and second antenna 46 during the fine alignment procedure for the first antenna 26 . To achieve this configuration, first installer 517 removes power source A from first antenna 26 and replaces it with power detector B 570 . Simultaneous with this removal and replacement a similar procedure is performed at the second antenna 46 . Second installer 527 removes power detector A from second antenna 46 and replaces it with power source B 560 .
Now second installer 527 turns on power source B 560 . The emitted power is directed toward first antenna 515 as a result of the fine alignment just performed. First installer 517 monitors the power detected by power detector B 570 while using small angular perturbations on the first antenna 26 to increase the strength of the received signal. Angular perturbations are continued along one axis until a maximum received signal is found. Then angular perturbations are performed along the other axis until a new, and larger, maximum received signal is found. This procedure is repeated, alternating between the two axes until a global maximum is found which corresponds to the best alignment orientation for first antenna 26 .
Other procedures and variations are clearly possible through generally less desirable than the procedure described above. For example, an installation team could align both antennas while using only one set of power source and power detector (e.g., Set A comprising power source A and power detector A). This may seem a good way to minimize equipment cost for the installation team. There are at least two ways this could be done.
In the first case, the first half of the procedure (alignment of second antenna 46 ) would be identical with the procedure described above. Then to align the first antenna 26 , the installation team could use cell phones to talk information from the power detector A 520 over to first installer 517 during the second half of the procedure (alignment of first antenna 26 ). This procedure has been performed by the inventors, but is deemed awkward due the need for the second installer 527 to read meter 340 and speak via a cell phone to the first installer 517 . This feedback mechanism is less desirable due to time delays and errors involved in the process.
In the second case, power source A and power detector A can be used for the second half of the procedure (alignment of first antenna 26 ) as well as for the first half of the procedure (alignment of second antenna 46 ). However, this would necessitate and additional step of transporting the equipment a potentially long distance (up to 10 miles or more) to swap the locations of these alignment aids. Such a swap would overcome the feedback awkwardness just described for the first case alternative procedure, but the labor time cost of such a step is substantial and therefore should be avoided.
Keeping the Antennas Aligned
FIG. 16 shows an alignment assurance camera 200 mounted to a sighting telescope 210 mounted to an antenna 220 operating at millimeter wave frequencies. Sighting telescope 210 and alignment assurance camera 200 are rigidly mounted to antenna 220 so that a disturbance in the orientation of the axis of antenna 220 produces the same effect on the alignment of sighting telescope 210 . Alignment assurance camera 200 can operate in the visual band or in the infrared. For the purposes of monitoring during the night, infrared enhancement is preferred and can be provided at low cost by a wide variety of siliconbased CCD cameras or by newer silicon-based CMOS cameras. In some installations it may be desirable to use an image-intensified camera to assure that distinct images are received even during darkness.
Sighting telescope 210 can be, for example, a Model SPS20X40RD, with a fixed power 20 times magnification, objective diameter, equal to 40 mm and a field of view of 1.5 degrees, available from BSA Optics, Ft. Lauderdale, Fla. The alignment assurance camera 200 can be, for example, a Model XCam2 available from X10 Wireless Technology, Inc. Seattle, Wash. The XCam2 with XRay Vision software allows the user to transmit live color video to a computer and send digital snapshots to any remote computer via the Internet. The software can be set (locally or remotely) to update new images every 10 seconds or every 2 hours. The software can also be set to have the camera take a snapshot only if it detects motion either within the image or a shift of the entire image. The NOC operators can use a remote viewer on their local computer or they can have the software update a web site with new images or email the images to the NOC or elsewhere.
FIG. 17 shows a scene as observed from the position of the alignment assurance camera location. Typically sighting telescope 210 will be aligned parallel with the axis of antenna 220 and therefore not only be useful for alignment assurance but also useful in the process of the initial alignment itself. However, the primary purpose of the alignment assurance system is for the ongoing monitoring of alignment and the aiding in rapid reacquisition of alignment should realignment be needed. For the purposes of ongoing monitoring and realignment it may be desirable or even necessary, for the sighting telescope 210 to point in a direction other than directly toward the antenna at the other end of the data link (i.e. companion antenna). A primary reason this may be the case is that what is most important for the ongoing maintenance of the orientation of the antenna direction is a clear and distinct image be monitored by alignment assurance camera 200 . In some cases, a clear and distinct image may be difficult to obtain in the direction pointing directly toward the companion antenna. For example, the companion antenna may be sighted on the top of a mountain in an area often obscured by clouds. In this case, it is highly desirable to orient the sighting telescope 210 toward some other direction that preferably contains numerous high contrast objects that form a clear and distinct pattern, recognizable by a computer.
FIGS. 18A and 18B show two images of a magnified portion of the scene of FIG. 17 at different times (before and after the antenna has suffered an alignment shift). FIG. 18A shows an original, antenna-aligned image and FIG. 18B indicates a new image after the antenna has been rotated slightly out of alignment. The procedure for assuring proper antenna pointing is very simple. An original digital image is stored that corresponds to the output of alignment assurance camera 200 when the antenna 220 is properly aligned. Thereafter, recent electronic images are constantly acquired by alignment assurance camera 200 and transmitted to a network operations center (NOC) for processing. The recent images are compared with the original image to make sure that the recent images do not show evidence of any shift (which would correspond to a rotation in the mounting of antenna 220 ). In the unfortunate event that some disturbance has caused the recent images to shift relative to the original image, the NOC computer can alert the operator that a misalignment has occurred. In an alternative embodiment, a non-NOC computer can do the image analysis and alert a repair crew.
It is important to emphasize that each of the antennas have their own alignment assurance camera 200 mounted on them. As a result, if one antenna is somehow knocked out of alignment, that particular antenna can be rapidly identified. This is important because if a communication link goes down, it is known that there is a problem with at least one end of the link, but it would not otherwise be known in which end of the link the problem had occurred. With alignment assurance cameras 200 installed at both ends of the link, the culprit end can be rapidly and easily identified. This advanced feature of the instant invention is particularly valuable since the data links herein can be very long, up to 10 miles long or more. With this feature a potentially large repair cost can be avoided. The potentially large repair cost is associated with time delays of repair crews traveling back and forth between the widely separated end points of a communication link just to isolate which end of the link has experienced the disruptive failure.
Another feature worthy of note is that the alignment assurance cameras help repair crews determine if alignment is or is not the cause of the link disruption. Furthermore, if alignment is to blame, the alignment assurance cameras can be used to direct repair crews as to both the direction and extent that realignment needs to be done.
FIG. 19 is a schematic diagram of an out-of-band signaling system for communicating antenna alignment information to a NOC. An alignment telescope and camera system 510 are mounted to an antenna 505 and send image information to a frame grabber circuit 515 which in turn sends digital image data to a computer 520 . When the data-link is operating normally, computer 520 then sends image information to a switch/router 530 which then passes the image information via a transceiver 540 and antenna 505 through a network 550 and onward to a NOC 560 . Computer 520 is also provided with other transceiver performance data by an electrical diagnostics system 522 . This other transceiver performance data is also sent to switch/router 530 which then passes the other transceiver performance data via transceiver 540 and antenna 505 through network 550 and finally to NOC 560 .
When the data-link is not operating properly (e.g. when the data-link is down), out-of-band communications are used to send information to the NOC to help the operations team get the data-link back in proper operating order quickly and cost effectively. FIG. 19 shows an example of an out-of-band communications system that uses a cell phone network 570 . In this case, computer 520 sends image information via a modem 572 and cell phone 574 to cell phone network 570 that then passes the image information to NOC 560 . Since cell phone networks have relatively limited bandwidth, computer 520 processes the digital image data from the alignment telescope and camera system 510 to determine if-the recent images match the original image as described earlier. In this case, computer 520 is again provided with other transceiver performance data by electrical diagnostics system 522 . This other transceiver performance data is also sent via modem 572 and cell phone 574 to cell phone network 570 that then passes the image information to NOC 560 .
In an optional embodiment that has motorized pan and or tilt mounting of an antenna, it is also possible to use the image from the camera to realign the antenna without the necessity of sending a repair crew to the misaligned antenna. This is particularly valuable since it means that recovery time for a link can be reduced from days (in the case where certified antenna climbing personnel are in short supply) to seconds or minutes. The importance of this fast recovery becomes clear when the following fact is taken into account. Availability time of 99.999%, which is often targeted by land-line communications systems, corresponds to just 5 minutes of non-availability per year.
Other Embodiments
Any millimeter-wave carrier frequency consistent with U.S. Federal Communications Commission spectrum allocations and service rules, including MMW bands currently allocated for fixed point-to-point services at 57-64 GHz, 71-76 GHz, 81-86 GHz, and 92-100 GHz, can be utilized in the practice of this invention. Likewise any of the several currently-allocated microwave bands, including 5.2-5.9 GHz, 5.9-6.9 GHz, 10.7-11.7 GHz, 17.7-19.7 GHz, and 21.2-23.6 GHz can be utilized for the backup link. The modulation bandwidth of both the MMW and microwave channels can be increased, limited again only by FCC spectrum allocations. Also, any flat, conformal, or shaped antenna capable of transmitting the modulated carrier over the link distance in a means consistent with FCC emissions regulations can be used. Horns, prime focus and offset parabolic dishes, and planar slot arrays are all included.
Transmit power may be generated with a Gunn diode source, an injection-locked amplifier or a MMW tube source resonating at the chosen carrier frequency or at any sub-harmonic of that frequency. Source power can be amplitude, frequency or phase modulated using a PIN switch, a mixer or a biphase or continuous phase modulator. Modulation can take the form of simple bi-state AM modulation, or can involve more than two symbol states, e.g., using quantized amplitude modulation (QAM). Double-sideband (DSB), single-sideband (SSB) or vestigial sideband (VSB) techniques can be used to pass, suppress or reduce one AM sideband and thereby affect bandwidth efficiency. Phase or frequency modulation schemes can also be used, including simple FM, bi-phase, or quadrature phase-shift keying (QPSK). Transmission with a full or suppressed carrier can be used. Digital source modulation can be performed at any date rate in bits per second up to eight times the modulation bandwidth in Hertz, using suitable symbol transmission schemes. Analog modulation can also be performed. A monolithic or discrete-component power amplifier can be incorporated after the modulator to boost the output power. Linear or circular polarization can be used in any combination with carrier frequencies to provide polarization and frequency diversity between transmitter and receiver channels. A pair of dishes can be used instead of a single dish to provide spatial diversity in a single transceiver as well.
The MMW Gunn diode and MMW amplifier can be made on indium phosphide, gallium arsenide, or metamorphic InP-on-GaAs. The MMW amplifier can be eliminated completely for short-range links. The detector can be made using silicon or gallium arsenide. The mixer/downconverter can be made on a monolithic integrated circuit or fabricated from discrete mixer diodes on doped silicon, gallium arsenide, or indium phosphide. The phase lock loop can use a microprocessor-controlled quadrature (I/Q) comparator or a scanning filter. The detector can be fabricated on silicon or gallium arsenide, or can comprise a heterostructure diode using indium antimonide.
The backup transceivers can use alternate bands 5.9-6.9 GHz, 17.7-19.7 GHz, or 21.2-23.6 GHz; all of which are covered under FCC Part 101 licensing regulations. The antennas can be Cassegrainian, offset or prime focus dishes, or flat panel slot array antennas, of any size appropriate to achieve suitable gain.
While the above description contains many specifications, the reader should not construe these as a limitation on the scope of the invention, but merely as exemplifications of preferred embodiments thereof. The present invention is especially useful in those locations where fiber optics communication is not available and the distances between communications sites are less than about 15 miles but longer than the distances that could be reasonably served with free space laser communication devices. Ranges of about 1 mile to about 10 miles are ideal for the application of the present invention. However, in regions with mostly clear weather the system could provide good service to distances of 20 miles or more. Accordingly the reader is requested to determine the scope of the invention by the appended claims and their legal equivalents, and not by the examples given above. | Equipment and methods for aligning the antennas of two transceivers of a point-to-point wireless millimeter wave communications link and keeping them aligned. Each of two communicating antennas is equipped with a telescopic camera connected to a processor programmed to recognize landscape images. The processors are programmed to remember the pattern of the landscape as it appears when the antennas are aligned. Each of the cameras then view the landscape periodically or continuously and if the landscape in view changes by more than a predetermined amount a signal is provided to indicate a misalignment. An operator can then take corrective action or alternatively the antenna system can be configured for remote or automatic realignment based of feedback from the camera. In a preferred embodiment, the antennas are initially aligned by substituting a narrow band oscillator power source for the signal transmitting electronics associated with a first antenna and a power detector is substituted for the signal receiving electronics of associated with a second antenna. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation in part which claims priority from U.S. application Ser. No. 14/180,049 filed Feb. 13, 2014, itself a non-provisional application which claims priority from U.S. provisional application No. 61/764,259 filed Feb. 13, 2013.
FIELD OF THE DISCLOSURE
The present disclosure relates generally to drilling rigs, and specifically to slingshot rig structures for land drilling in the petroleum exploration and production industry.
BACKGROUND OF THE DISCLOSURE
Land-based drilling rigs may be configured to be traveled from location to location to drill multiple wells within the same area known as a wellsite. In certain situations, it is necessary to travel across an already drilled well for which there is a well-head in place. Further, mast placement on land-drilling rigs may have an effect on drilling activity. For example, depending on mast placement on the drilling rig, an existing well-head may interfere with the location of land-situated equipment such as, for instance, existing wellheads, and may also interfere with raising and lowering of equipment needed for operations.
SUMMARY
The present disclosure provides for a land based drill rig. The land based drill rig may include a first and a second lower box, the lower boxes positioned generally parallel and spaced apart from each other. The land based drill rig may further include a drill floor. The drill floor may be coupled to the first lower box by a first strut, the first lower box and first strut defining a first substructure. The drill floor may also be coupled to the second lower box by a second strut, the second lower box and second strut defining a second substructure. The struts may be hingedly coupled to the drill floor and hingedly coupled to the corresponding lower box such that the drill floor may pivot between an upright and a lowered position. The drill floor may include a V-door oriented to generally face one of the substructures.
The present disclosure also provides for a land based drilling rig. The land based drilling rig may include a first and a second lower box, the lower boxes positioned generally parallel and spaced apart from each other. The land based drill rig may further include a drill floor. The drill floor may be coupled to the first lower box by a first strut, the first lower box and first strut defining a first substructure. The drill floor may also be coupled to the second lower box by a second strut, the second lower box and second strut defining a second substructure. The struts may be hingedly coupled to the drill floor and hingedly coupled to the corresponding lower box such that the drill floor may pivot between an upright and a lowered position. The drill floor may include a V-door oriented to generally face one of the substructures. The land based drilling rig may further include a mast coupled to the drill floor. The land based drilling rig may further include a tank support structure affixed to the first or second substructure. The tank support structure may include a tank and mud process equipment. The land based drilling rig may further include a grasshopper positioned to carry cabling and lines to the drilling rig. The grasshopper may be positioned to couple to the drill floor generally at a side of the drill floor, and the side of the drill floor to which the grasshopper couples may face towards the first or second substructure
BRIEF DESCRIPTION OF THE DRAWINGS
The summary and the detailed description are further understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, there are shown in the drawings exemplary embodiments of said disclosure; however, the disclosure is not limited to the specific methods, compositions, and devices disclosed. In addition, the drawings are not necessarily drawn to scale. In the drawings:
FIG. 1 is a side elevation from the driller's side of a drilling rig consistent with at least one embodiment of the present disclosure.
FIG. 2 is an overhead view of a drilling rig consistent with at least one embodiment of the present disclosure.
FIG. 3 is a perspective view of a drilling rig consistent with at least one embodiment of the present disclosure.
DETAILED DESCRIPTION
The present disclosure may be understood more readily by reference to the following detailed description, taken in connection with the accompanying figures, which form a part of this disclosure. It is to be understood that this disclosure is not limited to the specific devices, methods, applications, conditions or parameters described and/or shown herein, and that the terminology used herein is for the purpose of describing particular embodiments by way of example only and is not intended to be limiting of the present disclosure. Also, as used in the specification, including the appended claims, the singular forms “a,” “an,” and “the” include the plural, and reference to a particular numerical value includes at least that particular value, unless the context clearly dictates otherwise. The term “plurality,” as used herein, means more than one.
FIG. 1 depicts a side elevation of drilling rig 10 from the “driller's side” consistent with at least one embodiment of the present disclosure. Drilling rig 10 may include drill rig floor 20 , right substructure 30 , and left substructure 40 . Right and left substructures 30 , 40 may support drill rig floor 20 . Mast 50 may be coupled to drill rig floor 20 . As would be understood by one having ordinary skill in the art with the benefit of this disclosure, the terms “right” and “left” as used herein are used only to refer to each separate substructure to simplify discussion, and are not intended to limit this disclosure in any way. V-door side 22 of drilling rig 10 may be located over right substructure 30 . The V-door side 52 of mast 50 may correspondingly face right substructure 30 . Pipe handler 24 may be positioned to carry piping through a V-door as understood in the art positioned on V-door side 22 of drilling rig 10 . In some embodiments, grasshopper 26 may be positioned to carry cabling and lines to drilling rig 10 . In other embodiments (not shown), V-door side 22 and mast V-door side may face left substructure 40 . In some embodiments, as depicted in FIG. 1 , blow out preventer 90 may be located between left substructure 40 and right substructure 30 , i.e. drilling rig 10 may be centered over a wellbore.
In some embodiments, tank support structure 80 and tanks 70 may be included in drilling rig 10 . Tank support structure 80 may be affixed to right substructure 30 or left substructure 40 by means known to those of ordinary skill in the art with the benefit of this disclosure, including, but not limited to, welding and bolting. As shown in FIG. 1 , tank support structure 80 may be affixed to left substructure 40 . Tank support structure 80 may be located on the opposite substructure from V-door side 22 of drilling rig 10 . Tanks 70 may, for example, be mud tanks, auxiliary mud tanks, or other tanks useful in drilling operations and may be located within tank support structure 80 . In some embodiments, mud process equipment 100 may also be mounted within tank support structure 80 . Mud process equipment may include, for example, shakers, filters, and other equipment associated with the use of drilling mud.
FIG. 2 depicts an overhead view of drilling rig 10 consistent with at least one embodiment of the present disclosure in which V-door side 22 of drilling rig 10 , drilling rig floor 20 , and tank support structure 80 are shown. In some embodiments, choke manifold 102 may likewise be located on the rig floor. In some embodiments, accumulator 104 may likewise be located on the rig floor. In some embodiments, accumulator 104 may be a Koomey Unit as understood in the art.
In some embodiments, substructures 30 , 40 may be fixed as depicted in FIGS. 1, 2 . In some embodiments, as depicted in FIG. 3 , substructures 30 ′, 40 ′, may pivotably support drill rig floor 20 . Drill rig floor 20 may be pivotably coupled to one or more lower boxes 130 by a plurality of struts 140 together forming substructures 131 , 133 . Lower boxes 130 may support drill rig floor 20 . Lower boxes 130 may be generally parallel to each other and spaced apart. Struts 140 may be hingedly coupled to drill rig floor 20 and to lower boxes 130 . In some embodiments, struts 140 may be coupled to lower boxes 130 and drill rig floor 20 such that they form a bar linkage therebetween, allowing relative motion of drill rig floor 20 relative to lower boxes 130 while maintaining drill rig floor 20 parallel to lower boxes 130 . Thus, drill rig floor 20 may be moved from an upper position as shown in FIG. 3 to a lower position while remaining generally horizontal.
In some embodiments, the movement of drill rig floor 20 may be driven by one or more hydraulic cylinders 150 . In some embodiments, when in the upright position, one or more diagonals 160 may be coupled between drill rig floor 20 and lower boxes 130 to, for example and without limitation, maintain drill rig floor 20 in the upright position.
In some embodiments, with reference to FIGS. 1-3 , as they are mounted directly to a substructure ( 30 or 40 ) of drilling rig 10 , one or more pieces of equipment may travel with drilling rig 10 during a skidding operation. For example and without limitation, equipment may include tanks 70 , mud process equipment 100 , choke manifold 102 , accumulator 104 , mud gas separators, process tanks, trip tanks, drill line spoolers, HPU's, VFD, or driller's cabin 106 . As such any pipe or tubing connections between or taken from tanks 70 , mud process equipment 100 , choke manifold 102 , and/or accumulator 104 may remain connected during the skidding operations. This arrangement may allow, for example, more rapid rig disassembly (“rigging-down”) and assembly (or “rigging-up”) of drilling rig 10 before and after a skidding operation.
Additionally, by facing V-door side 22 of drilling rig 10 toward one of the substructures 30 , 40 , equipment and structures that pass through the V-door 23 or to drilling floor 20 from V-door side 22 of drilling rig 10 may, for example, be less likely to interfere with additional wells in the well field.
One having ordinary skill in the art with the benefit of this disclosure will understand that the specific configuration depicted in FIGS. 1-3 may be varied without deviating from the scope of this disclosure.
Those skilled in the art will appreciate that numerous changes and modifications can be made to the preferred embodiments of the present disclosure and that such changes and modifications can be made without departing from the spirit of said disclosure. It is, therefore, intended that the appended claims cover all such equivalent variations as fall within the true spirit and scope of said disclosure. | The drilling rig includes a first substructure and a second substructure. The second substructure is positioned generally parallel to and spaced apart from the first substructure and generally the same height as the first substructure. The drilling rig further includes a drill floor coupled to the first and second substructures, where the drill floor positioned substantially at the top of the first and second substructures. | 4 |
REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of international application number PCT/EP2011/064840 filed on Aug. 29, 2011, which claims priority to German patent application number 10 201 0 036 033.3 filed on Aug. 31, 2010.
FIELD
[0002] The disclosure relates to an inverter.
BACKGROUND
[0003] Conventional photovoltaic (PV) inverters such as central or string inverters or inverters having a multiplicity of parallel strings carry out a number of additional functionalities in addition to their main task of converting the direct current produced by the PV generator to grid-compatible alternating current. Amongst others, these additional functionalities may be: communication with the user via an HMI (human-machine interface) or via other communication channels, grid monitoring functions, grid support functions, and safety functions.
[0004] Furthermore, the PV generator is kept at the maximum-power point by maximum-power point tracking (MPP tracking).
[0005] At the same time, the size of the PV generator is generally governed by the nominal power of the inverter, thus restricting the scalability of the overall photovoltaic system.
[0006] Since the current in a string is governed by the characteristics of its weakest PV module, only identical modules, or modules that are as similar as possible, of the same technology should be used within the string.
[0007] If the incident radiation on the PV generator is not homogeneous, for example because of partial shadowing, the maximum possible power cannot be extracted from the PV generator, because the PV modules have different optimum operating points (MPPs), which cannot be set individually in a series or parallel circuit.
[0008] The disadvantages of conventional PV inverters, like for example the restricted scalability, restrictions when modules of different types are used together and high sensitivity to incident radiation that is not homogeneous, are almost completely avoided when using inverters that are referred to as being close to the module, module-oriented or module-integrated (that is to say a dedicated inverter with an AC output and its own MPP tracking for each module, which is referred to in the following text as an AC module). However, if the intention is to integrate the additional functions mentioned at the beginning in an AC module, the specific price (costs related to the power) is considerably higher than for conventional PV inverters. Furthermore, the efficiency of the AC modules can, in principle, not reach the efficiency of conventional PV inverters. Until now, this has led to it not being possible to introduce AC modules to the market successfully.
SUMMARY
[0009] A system would therefore be desirable that combines the advantages of both technologies with one another. One aspect of the present disclosure is therefore an AC interface that is integrated in an inverter and via which the power from decentralized AC modules connected thereto is fed into a grid. An inverter such as this is also referred to in the following text as a basic inverter. This results in minor additional costs, while the costs of the decentralized AC modules can be drastically reduced, since their functionality can be reduced to the basic functions such as inversion and MPP tracking, with the additional functions mentioned above being provided by the basic inverter also for the proportion of the power that is produced by the AC modules.
[0010] This allows almost all building locations to be used better for PV installations. In particular, a system such as this represents a considerably more cost-effective variant than DC/DC controllers close to the module, so-called power optimizers.
[0011] The disclosure relates to an inverter for a photovoltaic system that partially or completely satisfies the following requirements and provides the following functionalities: conversion of the direct current provided by the PV generator in the photovoltaic system to grid-compatible alternating current, module-by-module optimized MPP tracking, high energy efficiency, low specific price, communication of the system with the user via a standard HMI, grid monitoring functions, grid support functions, adjustable reactive power (supply, reference, compensation), safety functions, simple and flexible scalability of the PV generator, use of different PV generator types and technologies (for example thin-film cells and monocrystalline cells) in one photovoltaic system, energy-optimized use of a PV generator that is not illuminated homogeneously (shadowing, different module alignment, etc.), and capability to use the PV inverter with or without galvanic isolation, in which case both types can also be used within the same photovoltaic system.
[0012] According to one embodiment an inverter comprises an inverter bridge for converting a DC voltage to a first AC voltage and a grid interface between the inverter bridge and the grid for converting the first AC voltage to the grid-compatible AC voltage for feeding into the grid. An AC interface via which one or more AC modules for feeding into the grid can be connected, is arranged between the inverter bridge and the grid interface.
[0013] It has been found that many installations have a part of the generator area that is freely illuminated homogeneously, without being impeded by obstructions that throw shadows, throughout the majority of the time of the year. For rural installations, this part normally represents the entire area. This part decreases as the area affected by shadowing obstructions increases. One typical example are roof areas with dormers that throw a shadow onto PV generators installed in the vicinity at some times over the course of the day. However, only in rare cases more than 50% of the generator area is affected. It is therefore worthwhile combining areas of the generator that are illuminated homogeneously and freely to form a unit, and to allow the power to be converted centrally in one inverter. This is the best solution in terms of energy and investment costs.
[0014] Decentralized power conditioning as close to the module as possible is the energetically best solution for parts that are not illuminated homogeneously at some times. AC modules, in particular, can be used for this purpose, since they can carry out MPP tracking independently of one another. In order to allow them to be designed as cost-effectively and energy-efficiently as possible, it is desirable to reduce the design of these devices to the necessary basic functions. This allows considerably better utilization of existing roof areas, since area parts for which the use was not economic when using previous system architectures become economic in this way.
[0015] According to the disclosure, the inverter is extended such that one or more AC modules can be connected to it by means of an AC interface. This allows the basic functions of the AC modules to be reduced, such that inclusion in the photovoltaic overall system is possible, even though direct connection of the AC modules for feeding power into a power grid would not be permissible.
[0016] It is apparent that the conversion of the DC voltage into the first AC voltage by the inverter bridge and the conversion of the first AC voltage into the grid-compatible AC voltage is accompanied with a conversion of a DC current into a first AC current and further into a grid-compatible AC current. The use of the term “voltage” in the claims is not limiting in this sense.
[0017] In one embodiment of the inverter, the grid interface has switch disconnectors for disconnecting the inverter from the grid and/or for connecting the inverter to the grid. In one embodiment the switch disconnectors are operated dependent on a state of the grid. Further, the state of the grid concerns a voltage and/or a frequency of an electrical current within the grid and/or an islanding condition. Switch disconnectors are means for controlling that power is fed into the grid in a grid-compatible manner.
[0018] In a further embodiment of the inverter, the grid interface has a filter device. The filter device is used to form a sine-like AC-voltage for feeding power into the grid. The filter is a further means to ensure that power is fed into the grid in a grid-compatible manner.
[0019] In a further embodiment of the inverter, the grid interface has a safety device. In yet a further embodiment of the inverter, the inverter has measurement points via which a current value via the inverter bridge and a current value via the AC interface can be recorded. The safety device as well as the measurement points allow to control that power is fed into the grid in a grid-compatible manner.
[0020] In a further embodiment of the inverter, the inverter has a communication unit for exchanging data with AC modules that are connected to the AC interface. It is advantageous in one embodiment that the communication unit is designed to exchange data via lines of the AC interface or is designed for wireless exchange of data. Further, in one embodiment the communication unit is designed to exchange data for one of the following purposes: remote control or remote diagnostics of connected AC modules; storage or transmission of measured values, breakdown or failures of connected AC modules; transmission of control signals to connected AC modules; and display of data of connected AC modules on a display unit of the inverter.
[0021] The communication unit allows for an integral controlling and monitoring of all modules of a photovoltaic system, i.e. also of the AC modules connected to the inverter via the AC interface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The invention will be described in the following text using example embodiments and with reference to the drawings. The illustrated figures shall be understood in an illustrative and non-restrictive manner and are intended to make it easier to understand the invention. In this case:
[0023] FIG. 1 shows a schematic illustration of a conventional inverter;
[0024] FIG. 2 shows a schematic illustration of a conventional inverter with a grid interface;
[0025] FIG. 3 shows a first embodiment of an inverter;
[0026] FIG. 4 shows a second embodiment of an inverter;
[0027] FIGS. 5 to 7 show further embodiments of an inverter with various arrangements of measurement points within the inverter; and
[0028] FIGS. 8 and 9 show further embodiments of an inverter.
DETAILED DESCRIPTION
[0029] FIG. 1 shows a photovoltaic system 100 with a conventional inverter 19 . The inverter 19 has an inverter bridge 21 , by means of which a direct current from a connected PV generator 10 can be converted to an alternating current. The inverter bridge 21 is connected to a grid 40 for feeding the power that is produced from the PV generator in the form of real power P inv and reactive power Q. The feeding can be monitored, synchronized and controlled via a central processor (CPU) 22 by means of the measurement points 24 , which are designed to measure current and/or voltage values. In this case, the PV generator 10 comprises a number of series-connected PV modules, which form a string. Frequently, a number of strings are connected in parallel, and are connected to the inverter.
[0030] Further optional elements of a conventional inverter 19 are shown in the photovoltaic system 100 in FIG. 2 . This inverter 19 also has an HMI 23 , with the aid of which operating values of the inverter 19 can be displayed and the operation of the system 100 can be influenced, for example, by presetting nominal values 28 for the real power P ref and/or reactive power Q ref to be provided by the system. These nominal values 28 can alternatively also be transmitted via a communication unit 26 , for example, as a value preset by an operator of the grid 40 . The inverter 19 also has a grid interface 30 via which the abovementioned additional functionalities can be provided by the inverter. In one embodiment the grid interface 30 contains electromechanical or electronic switch disconnectors 32 , in order to be able to disconnect the basic inverter from the grid 40 . Safety functions, such as detection of voltage, frequency and isolation faults as well as detection of undesirable islanding or fault current monitoring that is sensitive to all types of current, are carried out by the safety device 31 . The individual components of the grid interface 30 may in this case be connected centrally to the CPU 22 , and may be controlled by it, or may be connected directly to one another.
[0031] FIG. 3 illustrates one embodiment of a basic inverter 20 according to the invention. The basic inverter 20 is connected to the AC modules 50 via a connecting area 65 by an AC interface 60 that is integrated in the basic inverter 20 and that is arranged between the inverter bridge 21 and the grid interface 30 . The illustrated basic inverter 20 furthermore has a measurement point 61 that can be used to selectively determine the current fed in by the AC modules 50 . A PV system configuration can thus be implemented that is appropriate for the requirements mentioned above. The connecting area 65 may have one or more connections for AC modules 50 , in which case one or more AC modules 50 can be connected to each connection. The connected AC modules 50 are in this way likewise protected by the grid interface 30 without themselves having to carry out the protection functions provided by the grid interface 30 . The switch disconnectors 32 in the grid interface 30 are designed for the total power of the system 100 , as a result of which the AC modules 50 do not require their own grid interface or their own switch disconnectors. The basic inverter 20 may either be designed as an inverter without a transformer, or as an inverter with a high-frequency transformer, or as an inverter with a grid transformer.
[0032] The basic inverter 20 in FIG. 4 has a communication unit 26 that is designed for wireless communication, for example radio transmission. In this case, the communication unit 26 may communicate in a simple manner with the AC modules 50 via their communication units 51 , in order to transmit data in one or both directions, or else in order to control or to monitor the AC modules 50 . Alternatively, the communication may, of course, also be provided via dedicated signal lines or by modulation onto the AC lines. The HMI 23 can also perform control and display functions for the AC modules 50 via the control and display elements for the basic inverter. Remote evaluation, remote diagnostics and/or remote control can be provided for the AC modules 50 via the communication unit 26 of the basic inverter 20 . Measured values or records of events of the AC modules 50 , such as breakdown or failures, can likewise be stored or transmitted. It is also feasible to transmit control signals for the connected AC modules 50 .
[0033] In order to allow the feeding parameters of the inverter bridge 21 and of the connected AC modules 50 to be determined separately from one another, further measurement points are provided as compared to the conventional inverters 19 in FIGS. 1 and 2 . In FIGS. 3 and 5 , a further measurement point 61 is provided between the AC interface 60 and the grid interface 30 in order to additionally allow to record the sum current of the inverter bridge 21 and the AC interface 60 . The current fraction of the AC interface 60 can therefore be determined easily by subtraction.
[0034] Alternatively, FIG. 6 shows an additional measurement point 62 in the current path of the AC interface 60 for determining the different current fractions. A further, alternative arrangement of the measurement points, which is not shown, can be used to measure the total current of the connected AC modules 50 and the sum current of the overall system 100 , and to determine the current fraction of the inverter bridge 21 from this.
[0035] As shown in FIG. 7 , each connection of the connecting point 65 can also be equipped with a measurement point 63 in order to allow a selective recording of the current fractions from the AC modules 50 connected to the AC interface 60 , and, for example, to use this for installation monitoring.
[0036] Furthermore, FIG. 5 shows a grid interface 30 that has a filter device 33 . The filter device 33 is used to remove or to sufficiently damp AC voltage components from the AC voltage to be fed into the grid 40 that are not at the grid frequency. The filter device 33 may, for example, be in the form of an LC bandpass filter and may be designed such that it can provide this function both for the inverter bridge 21 and for the connected AC modules 50 . Alternatively, as is shown in FIG. 7 , a further filter device 34 can also be arranged between the connecting area 65 and the AC interface 60 , providing the filter function selectively for the connected AC modules 50 .
[0037] As additional elements, FIG. 6 also shows a disconnecting device 67 for each connection of the connecting area 65 . This can be controlled by the basic converter 20 such that the inverter or inverters that is or are connected to the respective connection can be selectively disconnected from the AC interface 60 by means of switches. In an operating variant, it is possible this way to record feeding parameters or to perform diagnostics of the connected AC modules 50 separately for the respective AC modules 50 or module groups connected to the various connections, such that the measured values determined by the further measurement points 61 , 62 can be associated with the AC modules 50 or with a group of AC modules. Alternatively, one single disconnecting device 67 can also be provided in order to disconnect all of the connected AC modules 50 . The disconnecting device can be integrated in all of the illustrated embodiments of the inverter according to the invention.
[0038] One connection of the connecting area 65 may be used as a reference input, and its current or feeding power can be recorded separately. It is then worthwhile installing a PV module, which is connected to an AC module 50 , at a point in the PV installation that is never shadowed by obstructions, and to connect the corresponding AC module to the reference input. Discrepancies between the specific power of the reference module and of the remaining installation, or parts of the remaining installation, can thus be assessed.
[0039] A further option for the use of the basic inverter 20 according to the invention is for power factor correction for a load. For this purpose, at least one load is connected to the AC interface 60 in addition to (optional) AC modules 50 . The basic inverter 20 can produce the reactive power demanded by the load itself via the measurement points at the input and at the grid connection, such that the overall photovoltaic system 100 behaves in a neutral form on the grid.
[0040] Nominal values 28 for the real power P ref and for the reactive power Q ref can be received via the communication unit 26 of the basic inverter 20 and transferred to the CPU 22 , in order to allow the output real power and reactive power of the system 100 to be regulated as required. This allows grid services to be implemented, although the AC modules 50 need not necessarily themselves be capable of providing reactive power. It is sufficient for the basic inverter 20 to be designed as a feeding unit capable of providing reactive power.
[0041] The above statements apply to three-phase systems analogously; the basic inverter according to the invention with an AC interface can be used in this way for single-phase or polyphase grids. In the case of a polyphase grid, power distribution can be carried out via the connected single-phase AC modules 50 by splitting the AC modules 50 between the various phases via the AC interface 30 . This power distribution can be controlled for the connected grid 40 by the basic inverter 20 in accordance with the requirements. In particular, it is considered to configure the assignment of the AC modules 50 to the phases they are feeding into to be variable in accordance with the requirements of the three-phase grid, for example in order to counteract grid unbalances.
[0042] By way of example, FIG. 8 shows an arrangement of the AC interface 60 in which the single-phase AC modules that are connected to the three connections of the connecting area 65 each feed into one of the three phases of the basic inverter 20 . All of the AC modules are in this case connected to a neutral conductor 66 of the basic inverter. A further measurement point 62 is in each case provided for each feeding point. Alternatively, FIG. 9 shows an arrangement in which one three-phase AC module can in each case be connected to each of the three connections of the connecting area 65 . Instead of the illustrated connection arrangement of the respective AC modules between a neutral conductor and a selected phase (star arrangement), it is likewise feasible to connect the AC modules between two selected phases (delta arrangement).
[0043] The operation of the external AC modules 50 is monitored with the aid of the measurement points 24 , 61 , 62 , 63 and an algorithm that is implemented in the CPU 22 , which means that in one operating variant of the invention there is no need for communication between the AC modules 50 and the basic inverter 20 . The AC modules 50 can therefore be designed very cost-efficiently, since their functionality can be reduced to inversion and MPP tracking. Monitoring of compliance with predetermined feeding parameters for the overall system 100 , such as nominal values of the reactive power and real power, can be ensured despite the unregulated feeding by the AC modules, since the basic inverter 20 can control the feeding from the inverter bridge 21 such that, overall, the feeding from the inverter bridge 21 and the AC modules 50 corresponds to the nominal values. This results in a cost-effective, efficient overall photovoltaic system. It is likewise possible to monitor the feeding operation of the AC modules 50 using the basic inverter 20 , and to produce an appropriate warning in the event of discrepancies that lead to the deduction that the AC modules 50 have failed, and to send or to indicate this warning by means of the communication unit 26 or the HMI 23 . There is no need for communication with the AC modules for this purpose; the discrepancies are detected on the basis of the feeding parameters of the AC modules connected to the AC interface 60 , which can be recorded selectively via the further measurement points 61 , 62 , 63 , as described above, even if it may in some cases not be possible to unambiguously identify which of the connected AC modules has failed.
[0044] The basic inverter 20 can be equipped with a residual-current circuit breaker that is sensitive to all types of current. This allows the AC modules 50 to be configured as transformer-less inverters, and without their own safety components sensitive to all types of current, while still complying with existing safety regulations.
[0045] In one advantageous configuration, the photovoltaic system 100 is designed such that the part of the generator area that is at any time unshadowed feeds into the connected grid 40 via the inverter bridge 21 . The part of the generator area that is shadowed at least at some times is included in the system 100 via the AC interface 60 by means of the AC modules 50 . In general, that part of the area that is always unshadowed will make up the majority of the total generator area, such that the basic inverter 20 is advantageously configured such that the maximum power to be fed via the inverter bridge 21 is at least as high as the maximum power to be fed via the AC interface 60 . This results in the components of the basic inverter 20 being used particularly efficiently, while at the same time reducing the complexity for the overall photovoltaic system 100 , by means of the described joint use of certain components. | An inverter for feeding a grid-compatible AC voltage into a grid is described, wherein the inverter includes an inverter bridge for converting a DC voltage to a first AC voltage and a grid interface between the inverter bridge and the grid for converting the first AC voltage to the grid-compatible AC voltage for feeding into the grid. An AC interface via which an AC module for feeding into the grid can be connected, is arranged between the inverter bridge and the grid interface. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method of lapping a bevel gear. The method of the present invention may be applied to lapping of, for example, spiral bevel gears and hypoid gears.
2. Description of the Related Art
The related art will be described by taking spiral bevel gears as an example. As shown in FIG. 6(A), a pair of spiral bevel gears comprise a first gear 100 in the shape of a pinion gear having a first toothed portion 101 with curved tooth traces, and a second gear 200 in the shape of a ring gear having a second toothed portion 201 with curved tooth traces. As indicated in FIG. 6(A), an axis Wa of the first gear 100 and an axis Wb of the second gear 200 intersect at a point Pa at a right angle.
Conventionally, in order to attain tooth precision, the first toothed portion 101 of the first gear 100 and the second toothed portion 201 of the second gear 200, which constitute a pair of spiral bevel gears, are subjected to a lapping treatment comprising positioning the gears 100, 200 in an arrangement shown in FIG. 6(A), driving the first gear 100 to rotate, and as a result engaging the first gear 100 with the second gear 200 while supplying lapping liquid to engaging portions through a supply pipe 300.
This lapping treatment provides superior precision to an engaging surface of the first toothed portion 101 and an engaging surface of the second toothed portion 201. Therefore, even when gears have been subjected to quenching and other thermal treatments, which often cause distortion, the application of this lapping treatment after the thermal treatments is advantageous in correcting effectively distortion of the engaging surfaces caused by the thermal treatments.
In recent years, there has been a demand to apply this lapping treatment more effectively, in order to improve the productivity of lapping treatment and the precision of gear teeth considerably.
By the way, Catalog No. 514 published by OHKURA GLEASON ASIA Co., Ltd. in Japan discloses a technique of lapping hypoid gears shown in FIG. 6(B). In the case of hypoid gears, a first gear 100 and a second gear 200 are designed to have neither intersecting nor parallel axes by offsetting an axis Wc of the first gear 100 with respect to a point Pa by a predetermined distance ΔL3.
The inventors of the present invention have found and confirmed by experiments that when lapping treatment is applied to hypoid gears, the effect of the lapping treatment is much enhanced. The reason why the lapping effect is improved is assumed as follows: When gears are designed to have non-parallel and nonintersecting axes of hypoid gears, lapping liquid is liable to slid, in the direction of tooth trace in the case of hypoid gears than in the case of only bevel gears, and the sliding causes microfine abrasive particles in the lapping liquid to roll.
If explanation is made with reference to planes 500 shown in FIG. 7 by way of example, reciprocation of the plates 500 in a sliding direction brings about rolling of microfine abrasive particles 502 sandwiched between the planes 500, whereby a lapping effect is improved. It is assumed that the method of the present invention can expect a similar improving effect.
SUMMARY OF THE INVENTION
The present invention has been conceived in view of the above circumstances.
It is a primary object of the present invention to provide a method of lapping a bevel gear more effectively, by placing a gear-shaped tool whose axis has the hypoid gear relation with respect to the bevel gear.
A method of lapping a bevel gear according to a first aspect of the present invention is a method of lapping at least one of a first gear and a second gear constituting a pair of bevel gears, which comprises:
placing at least one gear-shaped tool whose axis lies in a position offset by a predetermined distance with respect to an intersection with an axis of the at least one of the first gear and the second gear, and which is engaged with at least one of the first gear and the second gear, and
engaging the at least one of the first gear and the second gear with the at least one gear-shaped tool, while supplying lapping liquid to engaging portions so as to apply a lapping treatment to an engaging surface of a toothed portion of the at least one of the first gear and the second gear.
The first gear and the second gear used in the method according to the first aspect of the present invention constitute a pair of bevel gears. It is preferable that toothed portions of the first gear and the second gear are a spirally toothed portion with curved tooth traces.
The method according to the first aspect of the present invention can adopt both a single mode in which one gear-shaped tool is used and a double mode in which two gear-shaped tools are used, as mentioned below.
In a single mode according to the method of the present invention, a gear-shaped tool is placed whose axis lies in a position offset by a predetermined distance with respect to an intersection with an axis of one of the first gear and the second gear, and which is engaged with the one of the first gear and the second gear. Then, the one of the gears is engaged with the gear-shaped tool, while lapping liquid is supplied to engaging portions, so that a lapping treatment is applied to an engaging surface of a toothed portion of the one of the gears.
In a double mode according to the method of the present invention, a first gear-shaped tool is placed whose axis lies in a position offset by a predetermined distance with respect to an intersection with an axis of a first gear, and which is engaged with the first gear. Besides, a second gear-shaped tool is placed whose axis lies in a position offset by a predetermined distance with respect to an intersection with an axis of a second gear, and which is engaged with the second gear.
Then, while the first gear is engaged with the first gear-shaped tool and the second gear is engaged with the second gear-shaped tool, lapping liquid is supplied to respective engaging portions, thereby applying a lapping treatment to an engaging surface of a toothed portion of the first gear and an engaging surface of a toothed portion of the second gear.
The lapping liquid employed is generally liquid including microfine abrasive particles. The microfine abrasive particles may be alumina, CBN, or others which are generally used for lapping treatment, and the material of the microfine abrasive particles are not particularly limited.
The material of the first gear 1 and the second gear 2 is not particularly limited, but generally metal such as cast iron and steel.
According to the first aspect of the present invention, since a gear-shaped tool is provided which has the same relation as hypoid gears, it is possible to apply a improved lapping treatment to an engaging surface of a toothed portion of at least one of the first gear and the second gear, which constitute a pair of bevel gears. This is advantageous in improving precision of the engaging surface of the toothed portion. Accordingly, even when gears have been subjected to thermal treatment such as quenching, this is advantageous in reducing and obviating distortion of the thermal treatment.
BRIEF DESCRIPTION OF THE DRAWINGS
The exact nature of this invention, as well as other objects and advantages thereof, will be readily apparent from consideration of the following specification relating to the annexed drawings in which:
FIG. 1 is a perspective view of a pair of spiral bevel gears;
FIG. 2 is a diagrammatic plan view of the pair of spiral bevel gears;
FIG. 3 is a perspective view illustrating that the pair of spiral bevel gears are lapped by using a first gear-shaped tool and a second gear-shaped tool;
FIG. 4 is a diagrammatic plan view illustrating that the pair of spiral bevel gears are lapped by using a first gear tool and a second gear-shaped tool;
FIG. 5 is a schematic enlarged view illustrating the engagement of toothed portions;
FIG. 6(A) is a perspective view of a pair of spiral bevel gears, and FIG. 6(B) is a perspective view of a pair of hypoid bears; and
FIG. 7 is a schematic view for showing a sliding effect of a lapping agent.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Now, a preferred embodiment according to the present invention will be described with reference to FIGS. 1 to 4.
In this preferred embodiment, a first gear 1 and a second gear 2 constitute a pair of spiral bevel gears, as shown by a perspective view of FIG. 1. The first gear 1 is formed of metal such as cast iron and steel, has the shape of a pinion gear, and is provided with a first toothed portion 10 having curved tooth traces. The second gear 2 is formed of metal such as cast iron and steel, has the shape of a ring gear, and is provided with a second toothed portion 20 having curved tooth traces.
An axis P1 of the first gear 1 and an axis P2 of the second gear 2 intersect at a point Pc at a right angle. In other words, the first gear 1 and the second gear 2 do not have the same relation as hypoid gears. A plan view of the bevel gears shown in FIG. 1 is schematically shown in FIG. 2.
In this preferred embodiment, a first gear-shaped tool 4 in the shape of a ring gear is placed, as apparent from FIGS. 3 and 4. The first gear-shaped tool 4 is engaged with the first gear 1 in the shape of a pinion gear. In addition, a second gear-shaped tool 5 in the shape of a pinion gear is placed. The second gear-shaped tool 5 is engaged with the second gear 2 in the shape of a ring gear.
In this case, as apparent from FIGS. 3 and 4, the first gear-shaped tool 4 is placed in such a manner that an axis N1 of the first gear-shaped tool 4 is offset with respect to the axis P2 of the second gear 2.
Accordingly, the axis N1 of the first gear-shaped tool 4 is offset with respect to the axis P1 of the first gear 1 by a predetermined distance, i.e., ΔL1. Therefore, the first gear 1 and the first gear-shaped tool 4 have the same relation as hypoid gears, which have non-parallel, nonintersecting axes.
On the other hand, as apparent from FIGS. 3 and 4, the second gear-shaped tool 5 is placed in such a manner that an axis N2 of the second gear-shaped tool 5 is offset with respect to the axis P1 of the first gear 1.
Accordingly, the axis N2 of the second gear-shaped tool 5 is offset by a predetermined distance, i.e., ΔL2 with respect to the axis P2 of the second gear 2, in other words, offset with respect to the point Pc. Therefore, the second gear 2 and the second gear-shaped tool 5 have the same relation as hypoid gears, which have non-parallel, nonintersecting axes.
The first gear-shaped tool 4 and the second gear-shaped tool 5 are respectively formed of hard resin (for example, nylon resin), and have gear teeth cut so that the first gear-shaped tool 4 and the second gear-shaped tool 5 can function as master gears with high precision.
In this preferred embodiment, the first gear 1 is connected to a driving source such as a driving motor, and serves as a driving gear. Therefore, when the first gear 1 drives in the direction of the arrow A1 in FIG. 3, the first gear-shaped tool 4 which is engaged with the first gear 1 rotates in the direction of the arrow A2. Further, when the first gear 1 as a driving gear drives in the direction of the arrow A1, the second gear 2 which is engaged with the first gear 1 rotates in the direction of the arrow A3. Moreover, the second gear-shaped tool 5 which is engaged with the second gear 2 rotates in the direction of the arrow A4.
In the meanwhile, lapping liquid 87 is supplied to respective engaging portions by discharging the lapping liquid 87 respectively from a fore end of a first supply pipe 81 and a fore end of a second supply pipe 82. Thus, a lapping treatment is applied to an engaging surface of the first toothed portion 10 of the first gear 1. In a similar way, a lapping treatment is also applied to an engaging surface of the second toothed portion 20 of the second gear 2.
At this time in this preferred embodiment, although the axes of the first gear 1 and the second gear 2 do not have the same relation as those of hypoid gears, the axes of the first gear 1 and the first gear-shaped tool 4 are designed to have the same relation as those of hypoid gears as mentioned above, so that the engaging surface of the first toothed portion 10 of the first gear 1 are lapped satisfactorily. It is assumed that since the axes of the first gear 1 and the first gear-shaped tool 4 are designed to have the same relation as those of hypoid gears as mentioned above, a sliding effect is acted on the engaging surface, and the sliding causes abrasive particles to roll.
Similarly, although the axes of the first gear 1 and the second gear 2 do not have the same relation as those of hypoid gears, the axes of the second gear 2 and the second gear-shaped tool 5 are designed to have the same relation as those of hypoid gears, so that an engaging surface of the second toothed portion 20 of the second gear 2 are lapped satisfactorily.
As shown in FIG. 5, the first toothed portion 10 of the first gear 1 are provided with two sides of engaging surfaces 10a, 10b which oppose to each other. When the first gear 1 working as a driving gear is rotated in one direction, one engaging surface 10a is engaged with the first gear-shaped tool 4, so that a lapping treatment can be applied to the one engaging surface 10a. On the other hand, when the first gear 1 working as a driving gear is rotated in the opposite direction, the other engaging surface 10b is engaged with the first gear-shaped tool 4, so that the lapping treatment can be applied to the other engaging surface 10b.
This effect is also true with the second toothed portion 20 of the second gear 2, for the second toothed portion 20 of the second gear 2 is provided with two sides of engaging surfaces which oppose to each other.
Further, this preferred embodiment employs both the first gear-shaped tool 4 and the second gear-shaped tool 5 which can function as master gears. So, the engaging surface of the first toothed portion 10 of the first gear 1 is lapped by the first gear-shaped tool 4, and the engaging surface of the second toothed portion 20 of the second gear 2 is lapped by the second gear-shaped tool 5. This is advantageous in securing the pitch accuracy of the first toothed portion 10 of the first gear 1, and the pitch accuracy of the second toothed portion 20 of the second gear 2. Accordingly, this is advantageous in reducing or obviating transmission errors generating between the first gear 1 and the second gear 2.
In addition, in this preferred embodiment, when the first gear 1 as a driving gear is braked appropriately, the braking effect can be transmitted to the engagement of the first gear 1 and the first gear-shaped tool 4. This allows face pressure to increase, and as a result, an improvement in the lapping effect can be expected. In a similar way, the braking effect can be transmitted to the engagement of the second gear 2 and the second gear-shaped tool 5. This also allows face pressure to increase, and as a result, an improvement in the lapping effect can be expected.
Furthermore, in this preferred embodiment, since the first gear-shaped tool 4 and the second gear-shaped tool 5 are formed of resin, the first gear-shaped tool 4 and the second gear-shaped tool 5 more easily accept microfine abrasive particles contained in lapping liquid by way of being pricked than tools formed of metal. Therefore, microfine abrasive particles can be suppressed from pricking the engaging surface of the first toothed portion 10 of the first gear 1 which is to be used as a gear product, and the engaging surface of the second toothed portion 20 of the second gear 2 which is also to be used as a gear product. So, it is possible to suppress strange noise generation and lifetime shortening due to pricked microfine abrasive particles. This is advantageous in maintaining high quality of the first gear 1 and the second gear 2.
In the above preferred embodiment, the method of the present invention is applied to a pair of spiral bevel gears in which the first gear 1 and the second gear 2 have intersecting axes, but its application is not restricted to these.
The method of the present invention can also be applied to a first gear and a second gear which constitute a pair of hypoid gears each having a spirally toothed portion.
Specifically, in the case of hypoid gears shown in FIG. 6(B), a first gear-shaped tool may be placed in such a manner to be offset with respect to a first gear 100, while a second gear-shaped tool may be placed in such a manner to be offset with respect to a second gear 200.
Bevel gears to which the method of the present invention is applied do not necessarily have a spirally toothed portion, and may have a straightly toothed portion.
Although the first gear-shaped tool 4 and the second gear-shaped tool 5 are formed of resin in the above preferred embodiment, the material of the tools are not limited to resin, and may be cast iron.
The method of the present invention is not limited to only the preferred embodiment described above and shown in the drawings, and can be appropriately practiced in still other ways without departing from the spirit or essential character thereof. | This invention aims to provide a method of lapping a bevel gear effectively by placing a gear-shaped tool whose axis has the same relation with the axis of the bevel gear as those of hypoid gears. In a double mode, gear-shaped tools are placed whose axes lie in a position offset with respect to the axes of the first gear and the second gear and have the same relation as those of hypoid gears. The first gear is engaged with one gear-shaped tool and the second gear is engaged with the other gear-shaped tool, while lapping liquid is supplied to engaging portions, thereby lapping engaging surfaces of toothed portions of the first gear and the second gear. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. Appl. No. 10/025,767 filed Dec. 26, 2001, which is a continuation of U.S. Appl. No. 09/520,843 filed Mar. 8, 2000 that issued as U.S. Pat. No. 6,394,784 on May 28, 2002, the entire disclosures of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1 Field of the Invention
[0003] This invention relates generally to injection molding and more particularly to an injection molding nozzle having an integral electrical heating element surrounded by layered dielectric insulation.
[0004] 2. Related Art
[0005] Heaters for injection molding and hot runner applications are known in the prior art, as demonstrated amply by the following U.S. Pat. Nos. 2,991,423, 2,522,365, 2,769,201, 2,814,070, 2,875,312, 2,987,300, 3,062,940, 3,550,267, 3,849,630, 3,911,251, 4,032,046, 4,403,405, 4,386,262, 4,557,685, 4,635,851, 4,644,140, 4,652,230, 4,771,164, 4,795,126, 4,837,925, 4,865,535, 4,945,630, and 4,981,431.
[0006] Heaters are of course also amply known in non-injection molding applications, as shown for example in U.S. Pat. Nos. 2,088,586, 2,378,530, 2,794,504, 4,438,322 and 4,621,251.
[0007] There are in general three types of heaters known for use in the hot runner nozzles. The first is so-called “integral heaters” which are embedded or cast in the nozzle body. Examples of such nozzles are disclosed in the following patents: U.S. Pat. Nos. 4,238,671, 4,386,262, 4,403,405 and EP 765728. The second is so-called “independent external heaters” which have their own support and that can be removed and replaced. Essentially, in such a design, shown in FIG. 1 a, the heating element H is external to the nozzle body N. Heating element H comprises a resistance wire W surrounded by electrical insulating material E and is encased in a steel casing C. Examples of such nozzles are disclosed in the following patents: U.S. Pat. Nos. 3,553,788, 3,677,682, 3,831,004, 3,912,907, 4,588,367, 5,360,333, 5,411,393, 5,820,900, EP 748678, EP 963829 and EP 444748. The third is so-called “attached external heaters” which are positioned spirally around the exterior of the nozzle or the nozzle tip but cannot be removed therefrom by reason of being brazed or embedded in the nozzle surface. Referring to FIG. 1 b, heating element H′ is embedded in a groove G′ in nozzle body N′. Examples of such nozzles are disclosed in the following patents: U.S. Pat. Nos. 4 , 557 , 685 , 4 , 583 , 284 , 4 , 652 , 230 , 5 , 226 , 596 , 5 , 235 , 737 , 5 , 266 , 023 , 5 , 282 , 735 , 5 , 614 , 233 , 5 , 704 , 113 and 5,871,786.
[0008] Electrical heaters have been also used in the design of the so-called hot runner probes. Unlike the hot runner nozzles the hot runner probes do not comprise the melt channel. The probes are located inside the melt channel of the nozzle and thus create an annular flow. The melt is heated from the inside and this heating approach is not applicable to all materials and applications. Examples of such nozzles are disclosed in the following U.S. Pat. Nos. 3,800,027 3,970,821, 4,120,086, 4,373,132, 4,304,544, 4,376,244, 4,438,064, 4,492,556, 4,516,927, 4,641,423, 4,643,664, 4,704,516, 4,711,625, 4,740,674, 4,795,126, 4,894,197, 5,055,028, 5,225,211, 5,456,592, 5,527,177 and 5,504,304.
[0009] Injection molding nozzles having integral heaters typically have electrical heating elements, wound spirally around the nozzle, which offer an efficient response to the many critical process conditions required by modern injection molding operations. There has been a continuous effort in the prior art, however, to improve the temperature profile, the heating efficiency and durability of such nozzles and achieve an overall reduction in size. Most of these efforts have been aimed at improving the means of heating the nozzle.
[0010] For example, U.S. Pat. No. 5,051,086 to Gellert discloses a heater element brazed onto the nozzle housing and then embedded in multiple layers of plasma-sprayed stainless steel and alumina oxide. To avoid cracking of the ceramic layers caused by excessive thickness and the differing thermal properties of the ceramic and the stainless steel, Gellert employs alternating thin layers of stainless steel and alumina oxide. The heating element of Gellert is nickel-chrome resistance wire (i.e. see W in FIGS. 1 a and 1 b herein) extending centrally through a refractory powder electrical insulating material (i.e. see E in FIGS. 1 a and 1 b ), such as magnesium oxide, inside a steel casing (i.e. see C in FIGS. 1 a and 1 b ). The heating element is integrally cast in a nickel alloy by a first brazing step in a vacuum furnace, which causes the nickel alloy to flow by capillary action into the spaces around the heater element to metallurgically bond the steel casing of the element to the nozzle body. This bonding produces very efficient and uniform heat transfer from the element to the nozzle body.
[0011] Nozzles with this type of electrical heaters, however, are often too big to be used in small pitch gating due to the size of the insulated heater required. These heaters are also generally expensive to make because of complex machining required. Also, the manufacturing methods to make these nozzle heaters are complex and therefore production is time consuming.
[0012] U.S. Pat. No. 5,955,120 to Deissler which discloses a hot runner nozzle with high thermal insulation achieved by coating the electrical heater with layers of a thermally insulation materials (mica or ceramic) and high wear resistance material (titanium). Like Gellert, the heater element of Deissler has its own electrical insulation protection and thus can be placed in direct contact with the metallic nozzle body (see FIG. 2 of Deissler). Also the heater element of Deissler is attached to the nozzle by casting (brazing) a metal such as brass. Deissler is thus similar to Gellert in that it discloses an insulated and brazed heater element. Again, as with Gellert, such a device requires many additional steps to braze and insulate the heater and is therefore time consuming. Also, as with Gellert, the use of an insulated element makes the size of the heated nozzle not well suited for small pitch applications.
[0013] In an attempt to reduce nozzle size, U.S. Pat. No. 5,973,296 to Juliano shows a thick film heater applied to the outside surface of an injection nozzle. The nozzle heater comprises a dielectric film layer and a resistive thick film layer applied directly to the exterior cylindrical surface of the nozzle by means of precision thick film printing. The thick film is applied directly to the nozzle body, which increases the nozzle's diameter by only a minimal amount. Flexibility of heat distribution is also obtained through the ability to apply the heater in various patterns and is, thus, less limited than spiral designs.
[0014] There are limitations to the thick film heater, however. Thermal expansion of the steel nozzle body during heating can cause unwanted cracking in the film layers due to the lower thermal expansion of the film material. This effect is particularly acute after a large number of injection cycles. The cracks could affect the resistive film heater because it is not a continuous and homogeneous material (as is a wire), but rather the fine dried powder of the conductive ink, as disclosed in Juliano '296.
[0015] Another heated nozzle design is disclosed in U.S. Pat. No. 4,120,086 to Crandell. In one embodiment, Crandell '086 discloses an electrically heated nozzle having an integral heater comprising a resistance wire heater disposed between two ceramic insulating layers. The Crandell '086 nozzle is made by wrapping a metal nozzle body with flexible strips of green (i.e., unsintered) ceramic particles impregnated in heat dissipatable material, subsequently winding a resistance wire heating element around the wrapped green layer, wrapping a second layer of the flexible strips of green ceramic particles thereover, heat treating the assembly to bake out the heat dissipatable material and sinter the ceramic particles together, and then compacting the assembly to eliminate air voids in the assembly. In U.S. Pat. No. 4,304,544, also to Crandell, the inventor further describes the flexible green ceramic strips as comprising a body of green ceramic insulator particles which are impregnated in a heat dissipatable binder material. In the green state, such strips are pliable and bendable, permitting them to be wrapped around the metal nozzle core, but when baked, the strips become hard and the particles agglomerate into a mass.
[0016] The Crandell '086 and '544 nozzle has relatively thick ceramic layers, employs an awkward process for applying the ceramic layers and requires additional heat treatment steps in fabrication, Crandell '086 concedes that the baking step is time consuming (see column 5, lines 20-25) and therefore admits that the design is less preferable than other embodiments disclosed in the patent which do not utilize this method. Also, as mentioned above, it is desirable to reduce nozzle size, which is not possible with the thick ceramic strips of Crandell '086 and '144.
[0017] The use of ceramic heaters for both hot runner nozzle heaters and hot runner probe heaters is also disclosed in U.S. Pat. No. 5,504,304 to Noguchi. Noguchi, like Juliano, uses a printing method to form an electrical resistive wire pattern of a various pitch from a metal or a composite paste. A ceramic heater embodiment for a nozzle probe (shown in FIG. 1 of Noguchi) is made by printing various electrical resistive patterns shown in FIGS. 3 - 4 of Noguchi. Noguchi discloses a method whereby a mixture of insulating ceramic powder such as silicon carbide (SiC), molybdenum silicide (MOSi 2 ) or alumina (Al 2 O 3 ) and silicon nitride (SiN), and electrically conductive ceramic powder such as titanium nitride (TiN) and titanium carbide (TiC is sintered and kneaded into a paste, which is then printed in a snaking manner on the external surface of a cylindrical insulating ceramic body, as shown in FIG. 3 of Noguchi. The printing state is made denser in certain areas and, by so controlling the magnitude of the so-called “wire density,” a temperature gradient is given to the heater. The heater pattern can be formed using metals such as tungsten, molybdenum, gold and platinum. A ceramic heater embodiment for a hot runner nozzle is also disclosed in Noguchi (see FIG. 14 of Noguchi). This self-sustained ceramic heater is also made by wire-printing using the same paste or metals. The heater is placed over the nozzle body and is then sintered and kneaded into a paste comprising a mixture of insulation ceramic powder such as silicon carbide, molybdenum silicide or alumina and conductive ceramic powder such as titanium nitride and titanium carbide. The paste is printed in a single snaking line on the part where, again, the heater pattern is formed by applying temperature gradients by varying the magnitude of wire density across the part.
[0018] Although Noguchi introduces a wire-printing method to achieve a certain heat profile along the nozzle it does not teach or show how this wire-printing method is actually implemented. More detailed information about this wire-printing method is provided by the patentee's (Seiki Spear System America, Inc.) catalogue entitled “SH-1 Hot Runner Probe” (undated). According to the catalogue, the circuit pattern, which provides the resistance for heating, is screen printed direction onto a “green” or uncured ceramic substrate. The flexible “green” substrate with the printed circuit is wrapped around an existing ceramic tube and the complete unit is fired and cured to produce a tubular heater. The resistive circuit pattern is encased within the ceramic between the tube and the substrate and has no exposure to the outside atmosphere. The thermocouple is inserted through the center of the tubular heater and positioned in the tip area. Thermocouple placement in the probe tip gives direct heat control at the gate. The ceramic heater unit is then fixed outside the probe body. Thus, this Seiki Spear method of making a ceramic heater body according to Noguchi including a printed-wire is similar to the method disclosed in Crandell '086, with the exception that Crandell uses a self-sustained resistance wire wound spirally around the nozzle between two “green” ceramic layers. As with Crandell, as well, an additional sintering step is required to sinter the green ceramic layers.
[0019] Accordingly, there is a need for a heated nozzle which overcomes these and other difficulties associated with the prior art. Specifically, there is a need for a heated nozzle which is simpler to produce and yields a more compact design.
SUMMARY OF THE INVENTION
[0020] The present invention provides an injection molding nozzle which is smaller in diameter than most prior art nozzles but which does not sacrifice durability or have the increased manufacturing costs of previous small diameter nozzles. Further the nozzle of the present invention is simpler, quicker and less costly to produce than prior art nozzles and minimizes the number of overall steps required in production. In particular, the need for heat treating the dielectric materials of the heater is removed entirely, saving time, money and hassle in fabrication. Further, the apparatus of the present invention provides a removable and/or replaceable cartridge heater design which offers the advantage of low-cost repair or replacement of a low cost heater component, rather than wholesale replacement of an intricately and precisely machined nozzle. The methods of the present invention similarly provide reduced and simplified steps in manufacturing, as well as permitting precise temperature patterns to be achieved a nozzle more simply than with the prior art.
[0021] In one aspect, the present invention provides an injection molding nozzle comprising a nozzle body having an outer surface and at least one melt channel through the body, a first insulating layer having a chemical composition, the first insulating layer disposed on the nozzle body outer surface so as to substantially cover at least a portion of the nozzle body, at least one wire element disposed exterior to and in contact with the first insulating layer, the at least one wire element being connectable to a power supply capable of heating the wire element, a second insulating layer having a chemical composition, the second insulating layer disposed over the first insulating layer and the at least one wire element, the second insulating layer substantially covering the at least one wire element and at least a portion of the first insulating layer, and wherein the chemical compositions of the first and second insulating layers remain substantially unchanged once the layers are disposed on the nozzle body.
[0022] In a second aspect, the present invention provides an injection molding nozzle comprising a nozzle body assembly having an outer surface and at least one melt channel through the assembly, the assembly having a core and a surface layer disposed around the core, the surface layer forming at least a portion of the nozzle body assembly outer surface, the core being composed of a first metal and the surface layer being composed of a second metal, the second metal having a higher thermal conductivity than the first metal, a first insulating layer disposed on the nozzle body assembly outer surface so as to substantially cover at least a portion of the outer surface, at least one wire element disposed exterior to and in contact with the first insulating layer, the at least one wire element being connectable to a power supply capable of heating the wire element and a second insulating layer disposed over the first insulating layer and the at least one wire element, the second insulating layer substantially covering the at least one wire element and at least a portion of the first insulating layer.
[0023] In a third aspect, the present invention provides an injection molding nozzle comprising a nozzle body having an outer surface and at least one melt channel through the body, a first insulating layer disposed on the nozzle body outer surface so as to substantially cover at least a portion of the nozzle body, at least one wire element disposed exterior to and in contact with the first insulating layer, the at least one wire element being connectable to a power supply capable of heating the wire element, a second insulating layer disposed over the first insulating layer and the at least one wire element, the second insulating layer substantially covering the at least one wire element and at least a portion of the first insulating layer, and wherein the first insulating layer is between 0.1 mm and 0.5 mm in thickness.
[0024] In a fourth aspect, the present invention provides an injection machine for forming a molded article, the machine comprising a mold cavity, the mold cavity formed between a movable mold platen and a stationary mold platen, at least one injection molding nozzle connectable to a source of molten material and capable of feeding molten material from the source to the mold cavity through at least one melt channel therethrough, the at least one nozzle injection molding having a nozzle body having an outer surface and the at least one melt channel through the body, a first insulating layer having a chemical composition, the first insulating layer disposed on the nozzle body outer surface so as to substantially cover at least a portion of the nozzle body, at least one wire element disposed exterior to and in contact with the first insulating layer, the at least one wire element being connectable to a power supply capable of heating the wire element, a second insulating layer having a chemical composition, the second insulating layer disposed over the first insulating layer and the at least one wire element, the second insulating layer substantially covering the at least one wire element and at least a portion of the first insulating layer, and wherein the chemical compositions of the first and second insulating layers remain substantially unchanged once the layers are disposed on the nozzle body.
[0025] In a fifth aspect, the present invention provides an injection mold to form an article, the mold comprising a mold half capable of communication with a mold manifold, at least one injection molding nozzle in flow communication with the mold half through at least one melt channel, the at least one nozzle injection molding having a nozzle body having an outer surface and the at least one melt channel through the body, a first insulating layer having a chemical composition, the first insulating layer disposed on the nozzle body outer surface so as to substantially cover at least a portion of the nozzle body, at least one wire element disposed exterior to and in contact with the first insulating layer, the at least one wire element being connectable to a power supply capable of heating the wire element, a second insulating layer having a chemical composition, the second insulating layer disposed over the first insulating layer and the at least one wire element, the second insulating layer substantially covering the at least one wire element and at least a portion of the first insulating layer, and wherein the chemical compositions of the first and second insulating layers remain substantially unchanged once the layers are disposed on the nozzle body.
[0026] In a sixth aspect, the present invention provides an injection molding nozzle comprising the steps of providing a nozzle body, the nozzle body having an outer surface and at least one melt channel through the body providing a first insulating layer on the outer surface of the nozzle body, the first insulating layer having a chemical composition, the first insulating layer substantially covering at least a portion of the nozzle body outer surface, positioning at least one wire element exterior to and in contact with the first insulating layer, the at least one wire element being connectable to a power supply capable of heating the at least one wire element, providing a second insulating layer on the first insulating layer and the at least one wire element, the second insulating layer having a chemical composition, the second insulating layer substantially covering the at least one wire element and at least a portion of the first insulating layer, and wherein the chemical compositions of the first and second insulating layers remain substantially unchanged once the layers are provided on the nozzle body.
[0027] In a seventh aspect, the present invention provides an injection molding nozzle comprising the steps of providing a nozzle body, the nozzle body having an outer surface and at least one melt channel through the body positioning a self-supporting insulating sleeve around the nozzle body, the sleeve substantially covering at least a portion of the nozzle body outer surface positioning at least one wire element exterior to and in contact with the insulating sleeve, the at least one wire element being connectable to a power supply capable of heating the at least one wire element, providing a second insulating layer on the insulating sleeve and the at least one wire element, the second insulating layer substantially covering the at least one wire element and at least a portion of the insulating sleeve.
BRIEF DESCRIPTION OF THE FIGURES
[0028] For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made by way of example to the accompanying drawings.
[0029] The drawings show articles made according to a preferred embodiment of the present invention, in which:
[0030] [0030]FIGS. 1 a and 1 b are partial sectional views of heated nozzle configurations according to the prior art;
[0031] [0031]FIG. 2 is a sectional view of a portion of an injection molding system showing a heated nozzle according to a preferred embodiment of the present invention;
[0032] [0032]FIG. 3 is an enlarged sectional view of the nozzle of FIG. 2;
[0033] [0033]FIG. 4 is a further enlarged and rotated (90′ counter-clockwise) sectional view of the heater assembly of the nozzle of FIG. 2;
[0034] [0034]FIG. 5 is an enlarged sectional view, similar to FIG. 4, of an alternate embodiment of a nozzle heater assembly according to the present invention;
[0035] [0035]FIG. 6 is an enlarged sectional view, similar to FIG. 4, of another alternate embodiment of a nozzle heater assembly according to the present invention;
[0036] [0036]FIG. 7 is an enlarged sectional view, similar to FIG. 4, of a further alternate embodiment of a nozzle heater assembly according to the present invention;
[0037] [0037]FIG. 8 is an enlarged sectional view, similar to FIG. 4, of a yet further alternate embodiment of a nozzle heater assembly according to the present invention;
[0038] [0038]FIG. 9 is an exploded isometric view of an alternate embodiment of the nozzle heater of the present invention;
[0039] [0039]FIG. 10 is a sectional view of a further embodiment of the nozzle heater of the present invention;
[0040] [0040]FIG. 11 is an enlarged sectional view of another nozzle embodiment employing a heater according to the present invention;
[0041] [0041]FIG. 12 a is an isometric view of a straight wire element for use as a heater element of the present invention;
[0042] [0042]FIG. 12 b is an isometric view of a coiled wire element for use as a heater element of the present invention;
[0043] [0043]FIG. 13 a is an isometric view of a doubled and twisted straight wire element for use as a heater element of the present invention; and
[0044] [0044]FIG. 13 b is an isometric view of a doubled, coiled wire element for use as a heater element of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0045] A multi-cavity injection molding system made in accordance with the present invention is shown in the Figures generally at M. Referring to FIG. 2, a portion of injection molding system M is shown. A melt passage 10 extends from a common recessed inlet 12 in a manifold extension 14 to an elongated manifold 16 where it branches out to a number of outlets 18 . As can be seen, each branch 20 of melt passage 10 extends through a steel nozzle 22 , having a central melt bore 24 in communication with melt passage outlet 18 from manifold 16 to a gate 26 leading to each cavity 28 . Nozzle 22 is a heated nozzle having a heater 30 according to a preferred embodiment of the invention, as described in greater detail below.
[0046] Manifold 16 is heated by a heating element 32 , which may be integrally brazed into it. Manifold 16 is held in place by a central locating ring 34 and insulating pressure pads 36 . Locating ring 34 bridges an insulative air space 38 between manifold 16 and a cooled spacer plate 40 . Pressure pads 36 provide another insulative air space 42 between manifold 16 and a cooled clamp plate 44 . Spacer plate 40 , clamp plate 44 and cavity plate 46 are cooled by pumping cooling water through a plurality of cooling conduits 48 . Clamp plate 44 and spacer plate 40 are secured in place by bolts 50 which extend into cavity plate 46 . Manifold extension 14 is held in place by screws 52 and a locating collar 54 which is secured to the clamp plate 44 by screws 56 .
[0047] Each nozzle 22 is seated in a well 58 in spacer plate 40 . An insulative air space 64 is provided between heated nozzle 22 and the surrounding cooled spacer plate 40 .
[0048] Referring to FIGS. 2 and 3, nozzle 22 has a body 68 having a steel central core portion 70 , an outer surface 72 , and a tip 74 , which is seated in gate 26 . Tip 74 has a flow channel 76 which is aligned with central melt bore 24 . Nozzle 22 is seated and secured in manifold 16 by a threaded portion 78 . Heater assembly 30 has an electrical resistive-wire heating element 80 , having a cold pin connections 82 for connecting wire element 80 to a power supply (not shown). Heater assembly 30 also has a first insulating layer 84 and a second insulating layer 86 disposed on either side of wire element 80 , so as to “sandwich” element 80 therebetween. First layer 84 is positioned on core 70 , with wire element 80 wrapped therearound, and second layer 86 positioned thereover. An outer steel layer 88 is provided to finish nozzle 22 . These layers are provided in a manner as will be described in more detail below.
[0049] Wire element 80 is a simple, bare, electrically and thermally uninsulated wire, preferably of thirty (30) gauge chromium nickel, though any wire material having resistive heating characteristics may be employed. Wire element 80 is preferably wrapped around nozzle 22 , and may be provided in any arrangement which provides the temperature distribution desired for a particular application. For example, in the embodiment of FIG. 3, successive windings of wire element 80 are closer together at the ends of nozzle 22 , where more heat is typically required, with a more spaced distribution occurring in the central portion of nozzle 22 .
[0050] According to the present invention, first layer 84 and second layer 86 are dielectric materials which can be applied in a “finished” (i.e. “non-green”) state to the nozzle body. In other words, the dielectric material does not require additional heat treating steps once it is applied to the nozzle assembly, and thus has a chemical composition which does not change after it is applied to the apparatus and the material does not require heat treating of sintering to achieve its “finished” state. In addition to this constraint, first layer 84 is also preferably a dielectric material which can withstand the high operating temperatures and heater wattages experienced in hot runner injection molding. As one skilled in the art will understand, the dielectric is preferably a good thermal conductor with low heat capacity, a combination which encourages rapid heating (and cooling) with maximum efficiency. The dielectric should also be a good electrical insulator, since wire element is otherwise uninsulated from nozzle 22 . The choice of material depends also on the temperature target for the molten material which will flow through the melt channel of the nozzle.
[0051] Illustrative of the dielectric materials which can be used in the practice of this invention are: aluminum oxide; magnesium oxide; mica coatings; Vespel™ (trade mark of E. I. Du Pont de Nemour & Company), graphite; alumina; alumina-silica; zirconia-based materials, such as tetragonal zirconia polycrystals (TZP) partially stabilized zirconia (PSZ), fully stabilized zirconia (FSZ), transformation toughened ceramics (TTC), zirconia toughened alumina (ZTA) and transformation toughened zirconia (TTZ); Cerama-Dip™ 538N (trade mark of Aremco Products Inc.), a zirconium silicate-filled water-based high temperature dielectric coating for use in insulating high-power resistors, coils and heaters; and Ceramacoat™ 538N (trade mark of Aremco Products Inc.) is a silica based, high temperature dielectric coating for use in insulating induction heating coils. Aluminum oxide is a preferred material because of its relatively high thermal conductivity.
[0052] Second layer 86 is provided to protect wire element 80 from the deleterious effects of the atmosphere, such as oxidation and corrosion, and to insulate the exterior of nozzle 22 electrically and thermally, so as to direct the output of heater assembly 30 towards the melt in flow channel 76 . Second layer 86 may be made from the same dielectric material as first layer 84 or a different material. In some applications, it may be desirable to use different materials. For example, the first layer 84 may be fabricated from a material having good electric insulating properties but high heat conductive characteristic, while the second layer 86 is of a material having high electric insulating properties and high heat insulating properties, so that the heat is directed to the central melt bore 24 within body 68 , while outer layer 88 remains cooler. The use of the same material, preferably aluminum oxide, for first layer 84 and second layer 86 is preferred.
[0053] First layer 84 and second layer 86 may be provided as particles or a liquid sprayed onto the nozzle apparatus, as a liquid “painted” onto the apparatus or as a solid, pre-fabricated, self-supporting sleeve, as described in more detail below. The layers may be provided in thicknesses as desired to suit a particular application. Thicknesses of the layers can range from 0.1 mm to 3 mm, and thicker, depending on the amount of insulating, overall nozzle diameter and method of fabrication desired, as will be described further below. Thicknesses in the range of 0.1 mm to 0.5 mm are preferred.
[0054] Outer layer 88 may be applied by spraying or by shrink-fitting a sleeve on second layer 86 . Outer layer 88 may have any desired thickness, though a thickness of about 1.5 mm is preferred.
[0055] Referring to FIGS. 4 - 7 , other embodiments of a nozzle heater according to the present invention are shown. In the embodiment of FIG. 5, a secondary wire element 90 is provided around second layer 86 , protected by a third insulating layer 92 . In this three-layer embodiment, second layer 86 is preferably a good heat conductor and electrical insulator while third layer 92 is a dielectric having good thermal insulating characteristics. Third layer 92 can be chosen from the same set of materials as described above for layers 84 and 86 . This embodiment permits a higher wattage heater to be obtained, at the obvious expense of a slightly larger nozzle diameter. Alternatively, secondary wire element 90 can provide redundancy for operational use if and when the primary wire element fails. FIG. 6 shows a configuration similar to FIG. 4, but with integral temperature sensors or thermocouple wire 94 and 96 positioned between first layer 84 and second layer 86 , wound spirally around nozzle 22 adjacent wire element 80 . Inclusion of thermocouples 94 and 96 allow for exacting temperature control in nozzle 22 , as will be understood by one skilled in the art. The thermocouples may be disposed immediately adjacent wire element 8 , as shown in FIG. 6, or may be provided between second layer 86 and third insulating layer 92 , as depicted in FIG. 7. In this embodiment, second layer 86 and third layer 92 preferably have similar characteristics as described above for the FIG. 5 embodiment.
[0056] Referring to FIG. 8, in a further alternate embodiment, a metal surface layer 98 is provided on outer surface 72 , between nozzle core 70 and first layer 84 . Surface layer 98 is a layer of a metal having a higher thermal conductivity than steel nozzle body 68 , such as copper and alloys of copper. Surface layer 98 thus promotes a more even distribution of heat from heater assembly 30 to the pressurized melt in central melt bore 24 . Surface layer 98 may be applied by spraying or by shrink-fitting a sleeve on core 70 . Surface layer 98 may have a thickness of between 0.1 mm to 0.5 mm, or greater if desired.
[0057] Referring to FIG. 9, in an alternate embodiment of the present invention, nozzle 22 ′ has a core 70 ′, a surface layer 98 ′ and a heater assembly 30 ′, which is composed of a first layer 84 ′, a wire element 80 ′, a second layer 86 ′ and an outer layer 88 ′. In this embodiment, surface layer 98 ′, first layer 84 ′, second layer 86 ′ and outer layer 88 ′ in fact, self-supporting, substantially rigid, annular telescoping sleeve components 98 a, 84 a, 86 a, and 88 a, respectively, which are pre-fabricated, prior to assembly of nozzle 22 ′, according to a method of the present invention, described below. This sleeve construction permits a heater assembly 30 ′ configuration which is selectively removable in part or in whole, depending on the design, from nozzle 22 ′ for periodic inspection, repair and/or replacement. Also, this sleeve construction permits the nozzle body to expand independently from the insulating layers, by virtue of the separate and self-supporting nature of the heater sleeves. Thus, when thermal expansion occurs in the nozzle, nozzle body 68 is free to grow longitudinally while the insulating sleeves and wire, which typically have lower thermal expansion characteristics, will not be subject to a mechanical stress induced by this nozzle body expansion. This feature has beneficial implications for increased heater durability.
[0058] The self-supporting annular sleeves of this embodiment may be made of any suitable dielectric material, as described above, that can be machined, molded or extruded into a thin-walled tube. As with the previous embodiments, it is desirable that the coefficient of thermal transfer to be higher for inner sleeve than the outer sleeve. Both sleeves are preferably made of the same materials.
[0059] Further, as one skilled in the art will appreciate, the various layers of a particular heater need not all be applied in an identical manner but rather a combination of layer types may be employed. One will further appreciate that the removability benefit of the sleeve embodiment requires that only at least one of the layers be a self-supporting sleeve, to permit it to be slidably removed from the nozzle assembly. For example, if first layer 84 ′ is provided as a self-supporting sleeve, second layer 86 may be applied directly to first layer 84 (and over wire element 80 , as well) by spraying or other coating method, as described further below. Conversely, in a particular application, it may be desirable to spray or otherwise coat a first layer 84 onto the nozzle body, and provide second layer 86 in a sleeve format In such a configuration, wire element 80 ′ may be integrally provided on the interior of the second layer sleeve element, so as to be removable therewith. Other combinations of layer construction are equally possible, as described below.
[0060] Referring to FIG. 10, in an alternate nozzle embodiment, heater assembly 30 ″ is disposed centrally within nozzle 22 ″. Heater 30 ″ has a core 70 ″, first layer 84 ″, wire element 80 ″, second layer 86 ″ and outer layer 88 ″. A removable nozzle tip 74 ″ is provided to permit heater assembly 30 ″ to be removed from nozzle 22 ″ for inspection, repair or replacement, as described above.
[0061] The present invention may be employed in any known injection molding nozzle design. Referring to FIG. 11, a two-part nozzle configuration according to the present invention is shown. A forward nozzle 100 has a heater assembly 102 according to the present invention, as described above, and a rearward nozzle 104 has a heater 106 according to the prior art, such as, for example, as is described in U.S. Pat. No. 5,051,086 to Gellert, incorporated herein by reference. Heater assembly 102 has a wire element 110 , a first insulating layer 112 and second insulating layer 114 , similar to that described above.
[0062] It will be apparent to one skilled in the art at the present invention can be employed using a straight wire 120 , as shown in FIG. 12 a, as element 80 to be wound spirally around the nozzle body, as described above. Equally, however element 80 may be a coiled wire 122 , as shown in FIG. 12 b, spirally wound around the nozzle. “Coiled” in this application means helical or spring-like in nature, as illustrated in FIG. 12 b. Coiled wire heating elements are well-known in the heating art as allowing for a reduction in heater power for a given operating temperature.
[0063] Similarly, referring to FIG. 13 a, it will be appreciated that the length of element 80 can be effectively doubled by folding over the wire element, and optionally twisted, to create a unitary element 124 . Element 124 , as expected, has twice the length of wire for a given element 80 length, and is twice as thick. Referring to FIG. 13 b, a coiled and doubled element 126 can equally be provided.
[0064] Referring again to FIG. 3, in use wire element 80 is energized by a power source (not shown). As current flows through wire element 80 , resistance to the electrical flow causes the wire to heat, as is well understood in the art. Heat generated by the element is preferably channelled and expelled substantially inwardly, by the presence first insulating layer 84 and second layer 86 , to heat the pressurized melt in central melt bore 76 . First layer 84 and second layer 86 also provide electrical insulation to electrically isolate wire element 80 from the surrounding metal components of the nozzle.
[0065] The uninsulated resistive wire heating element according to the present invention permits a cheaper heater to be obtained while permitting more exacting temperature distribution and control through more precise and flexible positioning of the element. Unlike the prior art, complex machining of the nozzle body and the need for integrally brazing the heating element to the nozzle body are removed, permitting savings in cost and time in fabricating the nozzle. Likewise, special and complex film printing techniques, materials and machinery are not required. Further, and perhaps most importantly, the present invention permits smaller diameter heated nozzle designs to be more easily achieved and more reliably operated than is possible with the prior art.
[0066] The heated nozzles of the present invention may be fabricated according to the method of the present invention. In a first embodiment of this method, steel nozzle body 68 is provided as the substrate for spraying first layer 84 thereon. First layer 84 may be provided by spraying, “painting” or otherwise coating in a thickness of between 0.1 mm and 0.5 mm. While greater thicknesses are possible, little benefit is attained by providing a thickness greater than 0.5 mm and, since it is generally desirable to minimize nozzle diameter, greater thicknesses are not typically preferred. First layer 84 is provided on outer surface 72 of nozzle body 68 so as to substantially cover, and preferably completely cover, outer surface 72 over the region where wire element 80 is to be located. After layer 84 is dry, wire element 80 is then positioned around first layer 84 , preferably by winding wire element 80 spirally around the exterior of the nozzle. Although any wire pattern is possible, winding is typically preferred because, among other things, it requires the simplest operation in automated production. With wire element 80 around first layer 84 , second layer 86 is then provided so as to substantially cover, and preferably completely cover, wire element 80 and thereby sandwich and encase wire element 80 between first layer 84 and second layer 86 . Second layer 86 is preferably applied by spraying, “painting” or otherwise coating to a thickness of between 0.1 mm and 0.5 mm (for reasons described above), though any other method of applying second layer 86 may be employed, including providing a sleeve as described below. Once second layer 86 is dry, metal outer layer 88 is provided. Metal outer layer 88 may be applied in any known manner, such as by spraying or by shrink-fitting a sleeve, with spraying being preferred in this embodiment to minimize the overall diameter of the nozzle. With the outer layer applied, the assembly is then typically swaged to compact the assembly and bring the overall nozzle diameter to within desired dimensional tolerances.
[0067] This embodiment of the method permits smaller diameter and more durable nozzles to be obtained than is possible with the prior art.
[0068] Further, the method is advantageous over the prior art since no additional heat treating step is required, thereby simplifying manufacture.
[0069] In an alternate embodiment of the method of the present invention, first layer 84 is provided as a pre-fabricated, self-supporting, substantially rigid, annular sleeve component which is telescopically, slidably positioned concentrically over core 70 . The sleeveless element may be cast, machined, molded or extruded into a thin-walled tube, and may be provided in any desired thickness, though thicknesses in the range of 1.5 mm to 2 mm are preferred to optimize thickness and durability of the sleeve component. The inside diameter of the first layer sleeve is preferably as small as possible while still permitting a sliding installation over core 70 , so as to minimize any air space between the two components. The next step is to position wire element 80 around the first layer sleeve and, as one skilled in the art will understand, it is not important whether the wire element is positioned around the first layer sleeve prior or subsequent to the sleeve's installation on the nozzle body. In fact, an advantage of the method of this embodiment is that the wire element can be pre-wired on the first layer sleeve prior to installation, which can offer flexibility and simplification in manufacturing. Once wire element 80 has been provided around the first layer sleeve, second layer 86 is then applied to substantially cover, and preferably completely cover, wire element 80 so as to sandwich and encase wire element 80 between the first layer sleeve and second layer 86 . Second layer 86 may be applied as a sleeve or by spraying, with the sleeve form being preferred in this embodiment. Again, it is not important whether second layer 86 is applied prior or subsequent to the installation of the first layer sleeve on the nozzle body. Second layer 86 , if applied in sleeve format, is sized to fit as closely as possible over wire element 80 on the first layer sleeve to minimize the air space between the first and second layers. A metal outer layer 88 is then applied to the outside of second layer 86 and may be applied by any known means, such as by spraying or by shrink-fitting a sleeve, with shrink-fitting a sleeve being preferred in this embodiment. Again, as will be understood by one skilled in the art, if a second layer sleeve is used, the outer layer may be applied to the second layer sleeve either pre- or post-installation of the second layer sleeve on the first layer sleeve or the nozzle assembly. With the outer layer applied, the assembly is then typically swaged to compact the assembly and bring the overall nozzle diameter to within desired dimensional tolerances. The assembly is then finished as required. Such finishing steps may include providing removable nozzle tip 74 to the nozzle assembly, if necessary in the particular application.
[0070] This embodiment of the method permits a removable heater assembly to be achieved. The first layer sleeve and/or second layer sleeve can be selectively removed from the nozzle body for inspection and/or replacement, if the heater is damaged or worn, without the need to replace the entire nozzle. Further, the independent nature of the sleeve elements permits the order of assembly to be varied as necessary, for example, by allowing the wire element to be provided on the first layer sleeve prior to installation on the nozzle body. Similarly, the second layer may be provided on first sleeve, over the installed wire, prior to installation of the first layer sleeve on the nozzle body. This advantage offers not only flexibility in manufacture but also permits the wire element to be more precisely placed on the first layer sleeve. For example, laying the wire over the sleeve and then spinning the sleeve so as to wind the wire onto the sleeve permits a precisely controlled pitch and pitch variation. A further advantage of the method is that no additional heat treating step is required, thereby simplifying manufacture.
[0071] It will be understood in the previous embodiment that, if desired, wire element 80 can equally be pre-installed in the interior of a second layer sleeve, rather than the outside of first layer sleeve.
[0072] In both of the above embodiments of the method of the present invention, a metal surface layer 98 of copper or other highly thermally conductive metal may be applied with advantage to the nozzle body prior to providing the first insulating layer, as described above with respect to the apparatus. In one aspect, the surface layer is applied by spraying. In another aspect, the surface layer is provided by shrink-fitting a sleeve onto core 70 of nozzle body 68 . As described above, the surface layer promotes thermal transfer between heater 30 and nozzle body 68 .
[0073] While the above description constitutes he preferred embodiment, it will be appreciated that the present invention is susceptible to modification and change without parting from the fair meaning of the proper scope of the accompanying claims. | The present invention provides an electrically heated nozzle for injection molding which is insulated to prevent conduction of electricity and loss of thermal transmission to the casing, with first and second electric heaters which can operate independently or simultaneously to heat the melt channel of the nozzle. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to ABS systems for road vehicles.
2. Description of the Related Art
Such systems operate by responding to an impending wheel-lock/skid condition at any particular wheel to reduce (dump) the actuating pressure applied to the brake associated with that wheel and to later re-apply the pressure when the tendency of that wheel to lock has reduced. A wheel-lock/skid condition is usually determined in such systems by detecting the occurrence of a predetermined drop (δv) in wheel speed (corresponding to a predetermined level of relative slip between the wheel and the road surface) following the achievement of a predetermined wheel deceleration (often identified as -b).
There is a trend for modern vehicle chassis to allow considerable rearward movement of the axles when bumps are encountered. This helps cushion the reaction felt at the passenger cabin, and thus contributes to improved comfort in the vehicle ride.
Unfortunately, any longitudinal compliance will also allow axle deflection when the tires are reacting to normal braking forces. If the deflection occurs in a short space of time, e.g. due to a sudden brake application, then it will be perceived by the ABS as a rapid fall in wheel speed. This is because rearward movement of the axle, taking place in a finite period of time, corresponds to a velocity in the opposite sense to that of vehicle motion.
Premature ABS activity may be triggered in prior art systems because these systems are unable to distinguish between normal adhesion-generated slip and transient axle deflection described above. This could only be avoided by setting the system's skid-detection thresholds at relatively insensitive levels. However, these may well be quite inappropriate to slower rates of pressure increase under which conditions the axle deflection takes place over a longer time period, such that the effect upon the perceived slip is insignificant.
Thus an awkward compromise must be achieved. Premature detection can delay the establishment of full deceleration levels and may also lead to driver complaints if the ABS intervenes under "normal" operating conditions. On the other hand, late detection (due to a lack of sensitivity) of an impending skid can also cause loss of performance due to excessive pressure overshoot, which precipitates high slip between the tire and road surface, needing considerable pressure reduction before the wheel will show signs of recovery. On a high-μ road surface, this recovery will be quite rapid, leading to a period of underbraking until the ABS can re-establish the correct pressure level. The resulting see-saw behaviour of the vehicle is also likely to draw driver criticism.
However, deflection-generated slip has a maximum value determined by the movement allowed and the maximum rate at which the braking force can be developed (determined by the characteristics of the brake actuating system). A typical maximum value for a passenger car is 6 km/h, although this will vary by a small amount (say ±1 km/h) according to the torsional stiffness of the tires.
SUMMARY OF THE INVENTION
In accordance with the present invention, the slip sensitivity of the system is arranged to be set to a relatively insensitive level at the first sign of an impending skid, is maintained at this level for a period corresponding to the time needed by the axle to move rapidly through its available deflection, and is arranged to be then restored in one or more stages to a normal level.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described further hereinafter, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 shows an example of how the wheel speed drop thresholds (Delta-V) might vary with speed in the application of the present invention;
FIG. 2 shows an example of how the minimum speed drop thresholds (minimum Delta-V) might vary progressively with each successive scan-period;
FIG. 3 illustrates, by way of a series of traces, the operational behaviour of a practical system constructed in accordance with the prior art;
FIG. 4 illustrates, by way of a series of traces, the operational behaviour of a practical system constructed in accordance with the present invention;
FIG. 5 is a flow chart illustrating the operation of one possible embodiment in accordance with the invention;
FIG. 6 is a block diagram of one embodiment of a first cycle threshold modified in accordance with the present invention;
FIG. 7 is a block diagram illustrating post detection threshold modification in accordance with the invention; and
FIG. 8 is a series of traces used to explain the operation of the apparatus of FIGS. 6 and 7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
As stated hereinbefore, in a system in accordance with the present invention, the slip sensitivity of the system is arranged to be set to a relatively insensitive level at the first sign of an impending skid, is maintained at this level for a period corresponding to the time needed by the axle to move rapidly through its available deflection, and is arranged to be then restored in one or more stages to a normal level.
For example, in a system wherein a skid is detected by monitoring the drop in wheel-speed following the achievement of a pre-determined wheel deceleration (e.g. 1.5 g), the speed-drop threshold might vary with speed in the manner shown in FIG. 1. Thus, at low vehicle speeds, the threshold is less than that which could be achieved by axle deflection alone, presenting a risk of premature ABS activity.
In a preferred arrangement in accordance with the invention, a pending cycle timer is arranged to be initialised when the wheel deceleration threshold (-b) has been reached, and will run for a number (e.g. a total of 36) controller scan-periods (e.g. of 7 ms each) irrespective of whether the wheel maintains the pre-determined deceleration or not. This is because the wheel deceleration may change to acceleration as the wheel resumes its normal running speed once the deflection has been taken up. At the same time, the speed-drop threshold (δv) is arranged to have a predetermined minimum value judged sufficient (e.g. 6 km/h) to prevent premature ABS activity. Once the timer has counted down through a span corresponding with the fastest practicable axle-displacement time (e.g. 7 scan-periods), this minimum value is reduced progressively (FIG. 2) with each successive scan-period so that the normal speed dependent δv threshold is restored.
This deflection-insensitive logic is not allowed to re-trigger until the pending cycle timer has expired. Its duration is judged so as to ensure that, should the wheel behaviour develop into a skid, this will be detected using normal δv sensitivity levels. However, the -b signal may have resulted from irregularities in the road surface, in which case the period during which the deflection-insensitive logic is inhibited should be short, so as to ensure that a subsequent brake application is correctly handled. Thus, the duration of the pending-cycle timer is selected to provide the best compromise between these two requirements.
In an advantageous embodiment/the pending cycle timer may be arranged to freeze for as long as the wheel deceleration exceeds another predetermined level (e.g. 1.0 g). This could occur at any point but would sensibly be confined to the section following the establishment of normal δv levels. The simplest case is to freeze the counter at its penultimate scan-period so that the deflection-insensitive logic cannot re-trigger immediately before a skid which had been developing at a slower-than-usual rate.
As a further precaution against premature ABS activity, first-cycle solenoid firings may be inhibited whenever the wheel deceleration is reducing. This allows the use of smaller minimum-δv levels.
If a high vehicle deceleration has already been established before the -b signal occurs (e.g. due to check braking below the adhesion limit), then most of the axle deflection will have already been taken-up. Under these circumstances an increased δv may cause pressure overshoot, resulting in more harm than good. One option is therefore to inhibit the deflection-insensitive first cycle logic when the vehicle deceleration exceeds a predetermined limit. A typical limit might be 50% g, but it is likely that it will be chosen to suit the particular vehicle type so as to ensure that subsequent deflection-induced premature firing does not occur until the deceleration has risen to at least, say, 80% g.
FIGS. 3 and 4 show typical behaviour in a practical situation of a single front wheel on a vehicle to which an ABS system is fitted and which suffers from the type of suspension arrangement discussed hereinbefore. FIG. 3 illustrates the reaction of a prior art system and FIG. 4 that of a system embodying the present invention.
In each case, the traces are identified as follows:
FL: ABS induced pressure dump when this trace is high
BrLi: Vehicle brake lights on when this trace is high.
aFL: The acceleration of the single front wheel.
VFL: The rotational speed of the single front wheel.
pFL: The pressure in the brake caliper at the single front wheel.
dvFL: The change in speed required at the single front wheel following a predetermined wheel deceleration for an incipient skid condition to be recognised. This is referred to as the slip detection threshold (δV).
The effect of this threshold has been super-imposed on the wheel speed trace to clarify the requirement for skid detection, i.e. that the wheel speed must fall below a speed equal to the wheel speed present at the time the pre- determined wheel deceleration threshold was exceeded MINUS the slip detection threshold.
aVeh: The longitudinal deceleration of the vehicle.
In general, an incipient skid condition is detected when a predetermined wheel deceleration has been exceeded followed by a predetermined change in wheel speed. The predetermined wheel deceleration threshold is called -B; the predetermined change in wheel speed is called δV.
In FIG. 3 (prior art), the calculated slip detection threshold is 2 kph. When the predetermined wheel deceleration threshold has been exceeded, the slip detection threshold is not increased. It can be seen that the skid detected based on this 2 kph threshold is too early. The wheel can sustain a braking pressure of over 100 bar, whereas the ABS-induced pressure dump has taken place when the pressure has reached only 60 bar. This results in a slow "attack" of the vehicle deceleration giving increased vehicle stopping distance.
In FIG. 4 (which represents an example of a system embodying the present invention), the calculated slip detection threshold is also 2 kph. However, when the predetermined wheel deceleration threshold has been exceeded, the slip detection threshold is increased following the rules described in the flowchart of FIG. 5, which prevents any skid detection taking place while the wheel's suspension movement is being absorbed. The magnitude, duration and decay rate of the increase in slip detection threshold are chosen dependent upon individual vehicle characteristics. The result of this action is that the first ABS-induced pressure dump is postponed until the pressure at the brake is of the order of 120 bar, resulting in a fast "attack" of the vehicle deceleration which reduces the vehicle stopping distance. (Because vehicle stopping distance is proportional to the square of the vehicle speed, a high deceleration while the vehicle speed is relatively high is more beneficial than a high deceleration when the vehicle speed is relatively low).
The various boxes identified in FIG. 5 are explained hereinafter as follows:
10--Deflection insensitive first cycle--FRONTS ONLY
12--Is calculated standard slip threshold>6 kph?
14--For this application example, the apparent slip developed due to suspension travel is less than 6 kph. Therefore if the normal slip detection threshold is 6 kph or more, no increase is required.
16--Any rear axle ABS activity?
18--For this application example, if ABS activity already exists on the rear axle (which is normally much less sensitive to suspension "wind up") then we do not try to defer front ABS operation.
20--Has the first cycle already happened on this wheel?
22--This application example is only considering suspension movement on the 1st cycle of each individual wheel.
24--Has deceleration of (-b) been detected?
26--(-b) is the predetermined wheel deceleration threshold.
28--Is the pending cycle timer running? ie. not equal to zero.
30--The pending cycle timer times the duration of any slip threshold increases and it used to inhibit retriggering of same.
32--CLEAR 1st cycle slip threshold increase and pending cycle timer
34--SET pending cycle timer to 250 ms 1st cycle slip threshold increase to 6 kph--calculated standard slip threshold.
36--Calculate new 1st cycle slip threshold increase=pending cycle timer--25 (apply maximum+6, minimum=0)--current slip threshold.
38--Is pending cycle timer==0?
40--Is pending cycle timer==1?
42--Is wheel deceleration more negative than -1 g?
44--Freeze the pending cycle timer at 1 while the wheel is still decelerating at a significant level. This prevents the 1st cycle slip threshold increase being retriggered in the case where a sustainable wheel deceleration has already been achieved.
46--DECREMENT Pending cycle timer.
48--Form new slip threshold=current slip threshold +1st cycle increase.
Reference is now made to FIG. 6 of the accompanying drawings which shows one embodiment of an ABS system incorporating a first cycle threshold modifier in accordance with the present invention.
Reference numeral 50 identifies a conventional wheel speed sensor associated with one of the vehicle wheels (not shown). The output signal from the sensor 50 is conditioned at 52 and passed to a unit 54 which calculates the wheel speed and deceleration and passes these to a wheel speed store 56 and wheel deceleration store 58, respectively. The stored current wheel speed is also held in a unit 60 and the wheel speed at the -b detection point is held at 62. The deceleration signal from store 58 is passed to one input (A) of a comparator 64 whose other input (B) is connected to a store 65 holding the value of -b. When input A≦B the comparator 64 provides an output firstly to the "store current wheel speed" unit 60 and secondly to one input of a NOT AND gate 66. The other input of the gate 66 is connected via an inverter 67 to a unit 68 which supplies a signal only when the ABS system is already active.
Vehicle speed and deceleration are calculated in a calculation unit 70 and the resulting speed and deceleration figures are stored in vehicle speed and vehicle deceleration stores 72,74, respectively. The vehicle speed signal is passed to a unit 76 where the slip threshold (δv) is calculated. The normal slip threshold is stored in a store 78 and passed to one input of a "select the highest" unit 80. The vehicle speed and vehicle deceleration signals are also passed to a calculation unit 82 where the deceleration threshold is calculated and passed to the (-b) store 65. The vehicle deceleration signal is also passed to one input (A) of a comparator 84, whose other input (B) receives a predetermined limit value from a limit store 86. When input A of comparator 84>input B, this comparator provides a signal to one input of an AND gate 86. A second input to the AND gate 86 is taken from the output of the NOT AND gate 66. A third input to the AND gate 86 is taken from a comparator 88 which provides an output when the pending cycle timer output, held in a store 90, is equal to zero.
The "select the highest" unit 80 receives further inputs from an "axle movement compensation constant" store 92 and from the AND gate 86. The unit 80 provides outputs which are directed to one input of a NAND gate 94, an "initialise the pending cycle timer" element 96, and a delta V (δv) store 98. The output of the AND gate 86 is also passed to the "initialise p.c.t." unit 96, whose output is fed to a store 100 which holds the pending cycle timer value. The store 100 is also connected to a "clear pending cycle timer" element 102 coupled to the output of the NAND gate 94. The latter gate has a second input connected to the "ABS already active" signal obtained from unit 68. Finally, the delta V store 98 is also coupled to the "ABS active already" signal from unit 68 via a unit 104 which is adapted to set the delta V (δv) level to the "normal slip threshold".
A description of the operation of the aforegoing system will follow hereinafter.
Turning now to FIG. 7, there is illustrated an example of post detection threshold modification, which is executed once per period (Scan) of the main control device.
In FIG. 7, a wheel speed store is shown at 200. Reference numeral 202 identifies a store which holds the measured speed at the -b detection point. The wheel speed signal is subtracted from the signal in the store 202 at an arithmetic unit 204 and passed to one input (A) of a comparator 206. The other input (B) of the comparator 206 is connected to a store 208 holding the delta V (δv) value. If A>B at the comparator 206, this provides a signal to an AND gate 210. The other input of the AND gate 210 is taken from the output of a further AND gate 212. On receipt of signals from both the comparator 206 and the AND gate 212, the AND gate 210 provides an activating signal to a drive solenoid 214, for achieving dumping (releasing) of the actuating pressure to the relevant brake actuator.
Wheel deceleration is stored in a store 216 and passed via an element 218 which acts to "save current wheel deceleration as "old" deceleration at end of period". The "old" deceleration is held in a store 220. The stored wheel deceleration is also passed by the store 216 to one input (A) of a comparator 222 and also to one input (B) of a comparator 224. The other input (B) of the comparator 222 receives a reference value from a store 224 representative of a deceleration of, for example, -1 g. If the inputs (A) and (B) to comparator 222 satisfy the condition that A≦B then comparator 222 provides an output to a NOT AND gate 226. The gate 226 receives a second input from a comparator 228 when the latter comparator detects that the pending cycle timer value in a pending cycle timer store 230 is equal to "one".
Further comparators 232 and 234 provide signals to an AND gate 236 when the value in the pending cycle timer store 230 is "not zero" and "not one", respectively. The AND gate 236 receives a further input from the NOT AND gate 226 and provides an output to a "decrement the pending cycle timer" unit 238 coupled back to the pending cycle timer store 230.
A further comparator 240 provides a signal indicative of the p.c.t. having "elapsed" by comparison of the value held in the p.c.t. store 230 with an element 242 which holds a preset value representative of the fastest practicable axle displacement time. The "elapsed" signal is provided to one input of an AND gate 244, whose other input is connected to the output of a comparator 246. The one (B) input of the comparator 246 receives a signal from a store 248 containing the "normal slip threshold" while its other (A) input is connected to the delta V store 208. If the inputs A and B of the comparator 246 satisfy the condition that B<A then a signal is passed to the AND gate 244. The output of the AND gate 244 is fed to a unit 246 which acts to decrement the delta V (δv) level, as illustrated diagrammatically in the sub-section of FIG. 7 marked E.
A still further comparator 248 has its one (B) input connected to a store 250 containing the "old wheel deceleration" and its other (A) input connected to the wheel deceleration store 216. This comparator 248 provides an output if its inputs A and B satisfy the condition that A≦B. The latter output is passed to the AND gate 212.
The second (A) input of the comparator 224 receives the -b level from a store 252. If the A and B inputs of the comparator 224 satisfy the condition that B≦A, then the comparator provides an input to the AND gate 212.
The second sub-section of FIG. 7, marked D, shows an example of the relationship between δv and the pending cycle timer value. Arrow F in this subdiagram indicates the initial value of the pending cycle timer. Arrow G indicates the "axle movement compensation constant". Arrow H indicates the level of the "normal slip threshold". Arrow J indicates how it is arranged for the system to freeze at 1 if wheel deceleration is <1 g. Arrow K indicates that otherwise the p.c.t. value is allowed to decay to zero.
The apparatus of FIGS. 6 and 7 operates as follows.
Wheel speed and deceleration values are calculated and held in stores 56,58 in a known manner by means of the elements 52 and 54. Similarly, vehicle speed and deceleration are calculated by element 70 and held in stores 72 and 74. The normal slip detection threshold 78 is calculated by element 76 as, for example, a function of the vehicle speed. The deceleration detection threshold in store 65 (-b) is calculated by element 82 as (for example) a function of the vehicle speed and the vehicle deceleration. If ABS is already signalled to be active on the vehicle by means of element 68, then the δv value in store 98 is set by the element 104 and the pending cycle timer is cleared to zero via the elements 68,94 and 102,--this latter operation marking that the deflection insensitive first cycle is not active.
In order for the deflection insensitive first cycle mechanism to become active, several conditions must he satisfied simultaneously. The current wheel deceleration at element 58 must become more negative than or equal to the stored -b threshold at store 65, see point A in FIG. 8. This test is performed at comparator 64. When the output of comparator 64 is true, the current wheel speed value at 56 is stored at 62 as "speed at -b detection" by operation of element 60. If, when the output of comparator 64 is true, ABS is not currently active on the vehicle a signal 68 and from element inverter 67 then provides a "first detection" on the output of AND gate 66. If the AND gate 86 receives at the same time a signal from comparator 84 indicating that the vehicle deceleration is less negative than the predetermined limit held in 86, the signal from the AND gate 66, and a signal from the comparator 88 indicating that the pending cycle timer 90 is equal to zero, then a new value for δv is stored at store 98 (FIG. 8, point B) which is selected by element 80 to be the higher of either the normal slip detection threshold at 78 or an Axle Movement Compensation constant (AMCC) held in store 92. If at the element 80 it is found that the AMCC is the higher value, the pending cycle timer is initialised to a predetermined value at 96. If the normal slip threshold is the higher, then the pending cycle timer 100 is cleared to zero at 102. Whenever the pending cycle timer is nonzero, the deflection insensitive first cycle detection is active.
Referring now to FIG. 7, when the deflection insensitive first cycle detection mechanism is enabled (pending cycle timer 100 not equal to zero), the pending cycle timer 100 is decremented by element 238 once per measurement period, provided that its current value is not equal to (for example) one, as determined by elements 234, 228 and 226. When the pending cycle timer 100 has been decremented at element 240 by a value corresponding to the time interval "Fastest Practicable Axle Displacement Time" held in store 242, (point C in FIG. 8), the stored value δv in element 98 is decremented at 246 provided it is determined by elements 246 and 244 to be still greater than the normal slip threshold in store 78 (see point D in FIG. 8). While these processes are executing, the current value of wheel slip is being calculated at 204 with respect to the wheel speed which existed when -b was first detected. If this is greater than the current value of δv held in store 208 and if the current value of wheel deceleration held in store 216 is more negative than or equal to -b and if it is determined at gate 212 that the current value of wheel deceleration at 216 is more negative than or equal to the old value of the wheel deceleration calculated in the previous controller measurement period and held in store 250 then the ABS solenoid 214 will be fired (point F in FIG. 8). | An anti-skid braking system for wheeled vehicles having fluid actuated brakes associated with the vehicle wheels. The anti-skid braking system includes speed sensors associated with the vehicle wheels, a scanning control device response to speed signals from the speed sensors to actuate a pressure dump device to periodically release the fluid pressure applied to the brake of any wheel which is determined, by detection of a predetermined level of relative slip between that wheel and the road surface to be about to lock. Later, the system, by detection, can re-apply the actuating pressure to that brake when the tendency of that wheel to lock has been reduced. Additionally, the system includes a control device adapted to adjust the magnitude of said predetermined level of relative slip to which said control device responds such as to reduce the slip sensitivity at the first sign of an impending skid condition, to maintain the slip sensitivity at this level for a period corresponding to the time needed by the axle to move rapidly through its available deflection, and to then restore the slip detection sensitivity to its normal level. | 1 |
This application claims the benefit of U.S. Provisional Application No. 60/113,606, filed Dec. 23, 1998.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention concerns methods for bleaching fabrics and household hard surfaces with peroxides sourced directly from air.
2. The Related Art
Oxygen bleaches are well known for their ability to remove stains from substrates. Traditionally the substrate, such as a fabric, is subjected to hydrogen peroxide or substances which can generate hydroperoxyl radicals. The latter may be inorganic or organic peroxides. Generally these systems must be activated. Temperatures of 60° C. and higher are effective to accomplish the activation. Unfortunately, high temperatures lead to inefficient cleaning. High temperatures can also cause damage to the substrates.
A preferred approach to generating hydroperoxyl bleach radicals is the use of an inorganic peroxide coupled with an organic precursor compound. These systems are employed for many commercial laundry powders. European systems are based on tetraacetyl ethylene diamine (TAED) in combination with sodium perborate or percarbonate. Well known in the United States is a laundry bleach product based on the precursor sodium nanoyloxybenzenesulphonate (SNOBS) coupled with sodium perborate. Precursor systems are effective yet they also exhibit several disadvantages. Precursors are moderately sophisticated organic molecules requiring multi-step manufacturing processes resulting in high capital costs. Secondly, precursor systems have large formulation space requirements; a significant percent of a laundry powder must be devoted to the bleach components leaving less room for other actives and complicating development of concentrated powders. Further, precursor systems do not bleach very efficiently in countries where consumers have wash habits entailing low dosage, short wash times, cold temperatures and low wash liquor to cloth ratios.
A long cherished dream has been to use air directly as the oxygen source. Air would avoid costly synthesized organic precursors and persalts.
Canadian Patent 2,183,814 (Reinhardt et al.) reports use of Polyoxometalates as bleaching catalysts for removal of stain from fabrics. The process requires an active-oxygen agent which may be hydrogen peroxide, organic peracids, inorganic peracids, organic persalts or inorganic persalts. Molecular oxygen or air are neither indicated nor suggested as the oxidation source.
WO 98/20101 (Mishra et al.) reports use of tungsten salts for catalyzing bleaching by hydrogen peroxide, percarbonates, perborates, various hydrogen peroxide adducts and mixtures thereof. Likewise, this disclosure requires that the source of oxygen be a liquid or a solid peroxy chemical. This patent is focused upon the removal of stains from various hard surfaces and textiles.
Accordingly, it is an object of the present invention to provide a bleaching system with stain removal efficacy based on molecular oxygen.
Another object of the present invention is to provide a bleaching system which is cost-effective and environmentally friendly.
Still another object of the present invention is to provide a bleaching system based on molecular oxygen operable at relatively low temperatures, short contact times and low dosage requirements.
These and other objects of the present invention will become more readily apparent from the following summary and detailed description.
SUMMARY OF THE INVENTION
A method for bleaching laundry or household surfaces is provided which includes:
(i) providing a wash medium with a bleaching composition comprising polyoxometalates; and
(ii) contacting a stained substrate for a time and in an amount sufficient to remove the stains; and
wherein air is employed as a primary source of oxygen atoms for bleaching.
DETAILED DESCRIPTION OF THE INVENTION
Now it has been discovered that stains can be removed simply by air oxidation through the catalysis of Polyoxometalates. Expensive oxygen bleaching agents such as hydrogen peroxide, organic peracids, inorganic peracids, organic persalts, inorganic persalts, Caro's acid, Caroates and bleach precursors are found to be unnecessary.
A polyoxometalate is an essential feature of the present invention. Polyoxometalates are inorganic complexes which are transition metal-oxygen-anion clusters. They have defined oligomeric or polymeric structural units which form spontaneously under appropriate conditions in an aqueous medium from simple compounds of vanadium, niobium, tantalum, molybdenum or tungsten. The polyoxometalates are subdivided into isopoly- and heteropolyoxometalates. (see M. T. Pope. Heteropoly and Isopoly Oxometalates, Springer-Verlag, Berlin, 1983).
Isopolyoxometalates are the simpler of the forms. They can be described as binary, i.e. containing only metal ion and oxygen, oxide anions of the formula [M m O y ] p- . Typical examples are [Mo 2 O 7 ] 2- , [WO 7 O 24 ] 6- , [Mo 6 O 19 ] 2- and [Mo 36 O 112 ] 8- .
In contrast, heteropolyoxometalates also contain further non-metal, semi-metal and/or transition metal ions. Heteropolyoxometalates of the general form [X x A a M m O y ] p- , where X is a nonmetal or semi-metal ion and A is a transition metal ion, possess one or more so-called heteroatoms X and/or A. One example is [PW 12 O 40 ] 3- (where X=P). By substitution of M m O y structural units in both isopoly- and heteropolyoxometalates for a transition metal ion A it is possible to introduce redoxidative transition metal ions of type A into the solid structures. Known examples include transition metal-doped, so-called Keggin anions of the formula [APW 11 O 39 ] 7-/8- where A=Zn, Co, Ni, Mn (J. Amer. Chem. Soc., 113, page 7209, 1991) and Dawson anions [AP 2 W 17 O 61 ] 7-/8- where A=Mn, Fe, Co, Ni, Cu (J. Amer. Chem. Soc. 109, page 402, 1987), which may also contain bound water of crystallization. Further substitutions, including different transition metal ions, are known, for example [WZnMn 2 (ZnW 9 O 34 ) 2 ] 12- (J. Amer. Chem. Soc. 116, page 5509, 1994). The charge of the above-described anions are compensated by protons (thereby giving the corresponding poly acids) or by cations (formation of poly-acid salts=heteropolyoxometalates).
For simplicity, the term polyoxometallate as used in the description embraces not only the salts of the polyacids but also the corresponding poly acids themselves.
The bleaching catalysts used in accordance with the invention preferably have the formula (1)
(Q).sub.q (A.sub.a X.sub.x M.sub.m O.sub.y Z.sub.z (H.sub.2 O).sub.b)cH.sub.2 O (1)
where Q, A, X, M, Z, q, a, x, m, y, z, b and c are defined as follows:
Q is one or more cations selected from the group consisting of H, Li, K, Na, Rb, Cs, Ca, Mg, Sr, Ba, Al, PR 1 R 2 R 3 R 4 and NR 1 R 2 R 3 R 4 , in which R 1 , R 2 , R 3 and R 4 are identical or different and are H, C 1 -C 20 -alkyl, C 5 -C 8 -cycloalkyl or C 6 -C 24 -aryl;
q is a number from 1 to 60, in particular from 1 to 40, and for monovalent countercations simultaneously describes the charge of the anionic unit;
A is one or more transition metals from subgroups 2 to 8, preferably Mn, Ru, V, Ti, Zr, Cr, Fe, Co, Zn, Ni, Re and Os, particularly preferably Mn, Ru, V, Ti, Fe, Co and Zn;
a is a number from 0 to 10, preferably from 0 to 8;
X is one or more atoms selected from the group consisting of Sb, S, Se, Te, Bi, Ga, B, P, Si, Ge, F, Cl, Br and I, preferably P, B, S, Sb, Bi, Si, F, Cl, Br and I;
x is a number from 0 to 10, preferably 0 to 8;
M is one or more transition metals selected from the group consisting of Mo, W, Nb, Ta and V;
m is a number from 0.5 to 60, preferably 4 to 10;
Z is one or more anions selected from the group consisting of OH - , F - , Cl - , Br - , I - , N 3 - , NO 3 - , ClO 4 - , NCS - , SCN - , PF 6 - , RSO 3 - , RSO 4 - , CF 3 SO 3 - , BR 4 - , BF 4 - , CH 3 COO - where R is H, C 1 -C 20 -alkyl, C 5 -C 8 -cycloalkyl or C 6 -C 24 -aryl;
z is a number from 0 to 10, preferably from 0 to 8;
O is oxygen;
y is the number of oxygen atoms required for structure/charge compensation, and
b and c independently of one another are numbers from 0 to 50, preferably from 0 to 30.
In the above formula q, a, x, m, y, z, b and c are preferably integers in their respective ranges.
Particular preference is given to the following polyoxometalates:
Q 5 CO(III)W 12 O 40 (Q=K, Na, NMe, NBu, or a mixture of these)
K 5 Mn(III)SiW 11 O 39
(Me 3 NH) 4 (NbO 2 )PW 11 O 39
Na 6 Co(III)AlW 11 O 40 H 2
K 10 [β-Cu 3 SiW 9 O 40 H 3 ]
K 9 [P 2 V 3 W 17 O 62 H 2 ]
Na 12 [WMn 2 (H 2 O) 2 (ZnW 9 O 34 ) 2 ]
Na 16 [Cu 4 (H 2 O) 2 (P 2 W 15 O 56 ) 2 ]
Na 10 [Mn 4 (H 2 O) 2 (PW 9 O 34 ) 2 ]
(NH 4 ) 14 [NaP 5 W 30 O 110 ]*
Table I lists a variety of polyoxometalates which were synthesized; most of these catalysts provided positive bleaching results with uptake of air as the oxygen source.
TABLE I__________________________________________________________________________Experimental Data Summary POM Sub-POM Class POM Formula Homo**o*__________________________________________________________________________Keggin Keggin H.sub.3 PW.sub.12 O.sub.40 X X H.sub.4 SiW.sub.12 O.sub.40 X X K.sub.6 Co(II)W.sub.12 O.sub.40 X K.sub.5 Co(III)W.sub.12 O.sub.40 X Lacunary K.sub.7 PW.sub.11 O.sub.40 X X K.sub.8 SiW.sub.11 O.sub.39 X X K.sub.8 SiW.sub.10 O.sub.36 X X β-Na.sub.10 SiW.sub.9 O.sub.34 X X Mono-TMSP K.sub.6 Mn(II)SiW.sub.11 O.sub.39 X K.sub.5 Mn(III)SiW.sub.11 O.sub.39 X K.sub.6 Co(II)SiW.sub.11 O.sub.39 X K.sub.5 Co(III)SiW.sub.11 O.sub.39 X K.sub.5 Fe(III)SiW.sub.11 O.sub.39 X K.sub.6 Cu(II)SiW.sub.11 O.sub.39 X K.sub.5 Mn(II)PW.sub.11 O.sub.39 X K.sub.4 Mn(III)PW.sub.11 O.sub.39 X K.sub.5 Co(II)PW.sub.11 O.sub.39 X K.sub.4 Co(III)PW.sub.11 O.sub.39 X K.sub.4 Fe(III)PW.sub.11 O.sub.39 X K.sub.6 Cu(II)PW.sub.11 O.sub.39 X K.sub.5 (NbO.sub.2)SiW.sub.11 O.sub.39 X Cs.sub.5 (NbO.sub.2)SiW.sub.11 O.sub.39 X Cs.sub.5 NbSiW.sub.11 O.sub.40 X (Me.sub.3 NH.sub.4 (NbO.sub.2)PW.sub.11 O.sub.39 X K.sub.5 VSiW.sub.11 O.sub.40 X X K.sub.7 Mn(II)AlW.sub.11 O.sub.40 H.sub.2 X Na.sub.6 Mn(III)AlW.sub.11 O.sub.40 H.sub.2 X Na.sub.6 Co(III)AlW.sub.11 O.sub.40 H.sub.2 X K.sub.6 CoAlW.sub.11 O.sub.40 X K.sub.6 VAlW.sub.11 O.sub.40 X Na.sub.6 VAlW.sub.11 O.sub.40 X X K.sub.6 MnBW.sub.11 O.sub.40 H.sub.2 X K.sub.7 VZnW.sub.11 O.sub.40 X K.sub.8 V(IV)Co(II)W.sub.11 O.sub.40 X Di-TMSP K.sub.6 V.sub.2 SiW.sub.10 O.sub.40 X X K.sub.7 VMnSiW.sub.10 O.sub.39 X X K.sub.7 VCoSiW.sub.10 O.sub.39 X X K.sub.6 VNbSiW.sub.10 O.sub.40 X X H.sub.5 PV.sub.2 Mo.sub.10 O.sub.40 X TBA.sub.5 PV.sub.2 Mo.sub.10 O.sub.40 X Cs.sub.5 PV.sub.2 W.sub.10 O.sub.40 X K.sub.4 [SiMn.sub.2 W.sub.10 O.sub.40 H.sub.6 ] X Tri-TMSP K.sub.7 V3SiW.sub.9 O.sub.40 X X H.sub.7 V.sub.3 SiW.sub.9 O.sub.40 X X K.sub.7 Mo.sub.2 VSiW.sub.9 O.sub.50 X X K.sub.6 V.sub.3 PW.sub.9 O.sub.39 X Cs.sub.7 (NbO.sub.2).sub.3 SiW.sub.9 O.sub.37 X Cs.sub.6 (NbO.sub.2).sub.3 PW.sub.9 O.sub.37 X K.sub.10 [β-Cu.sub.3 SiW.sub.9 O.sub.40 H.sub.3 X K.sub.5 H.sub.5 [α-Cu.sub.3 SiW.sub.9 O.sub.40 H.sub.3 ] XDawson Dawson K.sub.6 [α-P.sub.2 W.sub.18 O.sub.62 ] X X K.sub.6 [β-P.sub.2 W.sub.18 O.sub.62 ] X Lacunary K.sub.9 [α.sub.2 -P.sub.2 W.sub.17 O.sub.61 ] X K.sub.9 [α.sub.1 -LiP.sub.2 W.sub.17 O.sub.61 ] X Na.sub.12 [α-P.sub.2 W.sub.15 O.sub.56 ] X Mono-TMSP K.sub.8 [P.sub.2 CuW.sub.17 O.sub.62 H.sub.2 ] X X K.sub.8 [P.sub.2 Mn(II)W.sub.17 O.sub.62 H.sub.2 ] X Tri-TMSP K.sub.9 [P.sub.2 V.sub.3 W.sub.17 O.sub.62 H.sub.2 ] X XSandwich Keggin Na.sub.10 [Mn.sub.4 (H.sub.2 O).sub.2 (PW.sub.9 O.sub.34). sub.2 ] Na.sub.10 [Co.sub.4 (H.sub.2 O).sub.2 (PW.sub.9 O.sub.34).sub .2 ] Na.sub.10 [Cu.sub.4 (H.sub.2 O).sub.2 (PW.sub.9 O.sub.34).sub .2 ] Na.sub.12 [WMn.sub.2 (H.sub.2 O).sub.2 (ZnW.sub.9 O.sub.34).s ub.2 ] Na.sub.12 [WCo.sub.2 (H.sub.2 O).sub.2 (ZnW.sub.9 O.sub.34).s ub.2 ] Na.sub.12 [WCu.sub.2 (H.sub.2 O).sub.2 (ZnW.sub.9 O.sub.34).s ub.2 ] Dawson Na.sub.16 [Cu.sub.4 (H.sub.2 O).sub.2 (P.sub.2 W.sub.15 O.sub.56).sub.2 ] X Na.sub.12 [Fe.sub.4 (H.sub.2 O).sub.2 (P.sub.2 W.sub.15 O.sub.56).sub.2 ] X Pressyler (NH.sub.4).sub.14 [NaP.sub.5 W.sub.30 O.sub.110 ].31H.sub.2 O X__________________________________________________________________________ *"Hetero" refers to a heterogeneous protocol; see Example 2. **"Homo" refers to a homogeneous protocol; using stain mimic dye molecule (such as Red Acid 88) in a homogeneous medium
Under certain circumstances, reductants may provide additional improvement in bleaching activity. Typical but not at all limiting examples of useful reductants are sodium ascorbate and hydroxylamine. When present the reductant and polyoxometallate should be in a relative weight ratio from about 10,000:1 to about 1:100, preferably from about 1,000:1 to about 100:1.
Bleach systems of the present invention may be employed for a wide variety of purposes, but are especially useful in the cleaning of laundry. When intended for such purpose, the polyoxometallate will usually also be combined with surface-active materials, detergency builders and other known ingredients of laundry detergent formulations.
The surface-active material may be naturally derived, or synthetic material selected from anionic, nonionic, amphoteric, zwitterionic, cationic actives and mixtures thereof. Many suitable actives are commercially available and are fully described in the literature, for example in "Surface Active Agents and Detergents", Volumes I and II, by Schwartz, Perry and Berch. The total level of the surface-active material may range up to 50% by weight, preferably being from 0.5 to 40% by weight of the composition, most preferably 4 to 25%.
Synthetic anionic surface-active materials are usually water-soluble alkali metal salts of organic sulphates and sulphonates having alkyl radicals containing from about 8 to about 22 carbon atoms.
Examples of suitable synthetic anionic surface-active materials are sodium and ammonium alkyl sulphates, especially those obtained by sulphating higher (C 8 -C 18 ) alcohols produced for example from tallow or coconut oil; sodium and ammonium alkyl (C 9 -C 10 ) benzene sulphonates, sodium alkyl glyceryl ether sulphates, especially those ethers of the higher alcohols derived from tallow or coconut oil and synthetic alcohols derived from petroleum; sodium coconut oil fatty acid monoglyceride sulphates and sulphonates; sodium and ammonium salts of sulphuric acid esters of higher (C 9 -C 18 ) fatty alcohol-alkylene oxide, particularly ethylene oxide, reaction products; the reaction products of fatty acids such as coconut fatty acids esterified with isethionic acid and neutralized with sodium hydroxide; sodium and ammonium salts of fatty acid amides of methyl taurine; sarcosinate salts; alkane monosulphonates such as those derived by reacting alpha-olefins (C 8 -C 20 ) with sodium bisulphite and those derived by reacting paraffins with SO 2 and Cl 2 and then hydrolyzing with a base to produce a random sulphonate; sodium and ammonium C 7 -C 12 dialkyl sulfosuccinates; and olefin sulphonates, which term is used to describe the material made by reacting olefins, particularly C 10 -C 20 alpha-olefins, with SO 3 and then neutralizing and hydrolyzing the reaction product; and sulphates or sulphonated alkyl polyglucosides. The preferred anionic surface-active materials are sodium (C 11 -C 15 ) alkylbenzene sulphonates, sodium (C 16 -C 18 ) alkyl sulphates and sodium (C 16 -C 18 ) alkyl ether sulphates.
Examples of suitable nonionic surface-active materials which may be used, preferably together with the anionic surface-active materials, include in particular the reaction products of alkylene oxides, usually ethylene oxide, with alkyl (C 6 -C 22 ) phenols, generally 5-25 EO, i.e. 5-25 units of ethylene oxide per molecule; the condensation products of aliphatic (C 8 -C 18 ) primary or secondary linear or branched alcohols with ethylene oxide, generally 2-30 EO, and products made by condensation of ethylene oxide with the reaction products of propylene oxide and ethylene diamine. Other so-called nonionic surface-actives include alkyl polyglucosides, long chain tertiary amine oxides, and fatty amido polyols such as methyl glucamides.
Amphoteric or zwitterionic surface-active materials such as alkylamidopropyl betaines can also be used in the compositions of the invention. If any amphoteric or zwitterionic surface-actives are used, it is generally in small amounts in compositions based on the much more commonly used synthetic anionic and nonionic actives.
Soaps may also be incorporated into the compositions of the invention, preferably at a level of less than 30% by weight. They are particularly useful at low levels in binary (soap/anionic) or ternary mixtures together with nonionic or mixed synthetic anionic and nonionic compounds. Soaps which are used are preferably the sodium, or less desirably potassium, salts of saturated or unsaturated C 10 -C 24 fatty acids or mixtures thereof. The amount of such soaps can be varied between 0.5 and 25% by weight, with lower amounts of 0.5 to 5% being generally sufficient for lather control. Amounts of soap between 2 and 20%, especially between 5 and 15, are used to give a beneficial effect on detergency. This is particularly valuable in compositions used in hard water where the soap acts as a supplementary builder.
In systems where anionic surfactants such as linear alkylbenzene sulphonate are employed, it may be desirable to include a hydrotrope such as sodium benzene sulphonate to avoid micellization of the anionic surfactant and thereby improve the bleach effect.
The detergent compositions of the invention may normally also contain a detergency builder. Builder materials may be selected from (1) calcium sequestrant materials, (2) precipitating materials, (3) calcium ion-exchange materials and (4) mixtures thereof.
In particular, the compositions of the invention may contain any one of the organic or inorganic builder materials, such as sodium or potassium tripolyphosphate, sodium or potassium pyrophosphate, sodium or potassium orthophosphate, sodium carbonate, the sodium salt of nitrilotriacetic acid, sodium citrate, carboxymethylmalonate, carboxymethyloxysuccinate, tartrate mono- and di-succinate, oxydisuccinate, crystalline or amorphous aluminosilicates and mixtures thereof.
Polycarboxylic homo- and co-polymers may also be included as builders and to function as powder structurants or processing aids. Particularly preferred are polyacrylic acid (available under the trademark Acrysol from the Rohm and Haas Company) and acrylic-maleic acid copolymers (available under the trademark Sokalan from the BASF Corporation) and alkali metal or other salts thereof.
These builder materials may be present at a level of from 1 to 80% by weight, preferably from 10 to 60% by weight.
Upon dispersal in a wash water, the initial amount of polyoxometalate may range from about 0.001 to about 10 mmol/liter, preferably from about 0.01 to about 5 mmol/liter, most preferably from about 0.1 to about 1 mmol/liter of the aqueous wash liquid. Surfactant when present in the wash water may range from about 0.05 to about 1.0 grams per liter, preferably from about 0.15 to about 0.20 grams per liter. When present, the builder amount may range from about 0.1 to about 3.0 grams per liter.
Apart from the components already mentioned, the bleaching compositions of the invention may contain any of the conventional additives in he amounts in which such materials are normally employed in cleaning compositions. Examples of these additives include dye transfer inhibition agents such as polyamine N-oxide polymers, metallo phthalocyanines, and polymers based on N-vinylpyrrolidone and N-vinylimidazole, lather boosters such as alkanolamides, particularly the monoethanolamides derived from palmkernel fatty acids and coconut fatty acids, lather-depressants such as alkyl phosphates and silicones, anti-redeposition agents such as sodium carboxymethylcellulose and alkyl or substituted alkylcellulose ethers, stabilizers such as ethylene diamine tetraacetic acid and phosphonic acid derivatives (Dequest®), fabric softening agents, inorganic salts such as sodium sulphate, and, usually present in very small amounts, fluorescent agents, perfumes, enzymes such as proteases, cellulases, lipases and amylases, germicides and colorants.
The bleaching system of the present invention may be delivered in a variety of product forms including powders, on sheets or other substrates, in pouches, in tablets, in aqueous liquids, or in nonaqueous liquids such as liquid nonionic detergents.
Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this specification indicating amounts of material ought to be understood as modified by the word "about".
The following examples will more fully illustrate the embodiments of this invention. All parts, percentages and proportions referred to herein and in the appended claims are by weight unless otherwise illustrated.
EXAMPLE 1
Several synthesis of polyoxometalates are reported below. These are only for illustrative purposes of the general synthesis. Many polyoxometalates are also commercially available.
General
Phosphotungstic acid and tungstosilicic acid were purchased from Aldrich and Fluka. They were used without further purification. All other chemicals were obtained from the Fisher Scientific Company. The pH of the reaction was maintained using a Metrohm Titrator with a desired base. All 31 P and 29 Si NMR were acquired on a Bruker AC-500 MHz spectrometer.
Preparation of Potassium α-undecatungstosilicate, K 8 [α-SiW 11 O 39 ] 8
Into a 1 L Erlenmeyer flask equipped with a stir bar, tungstosillicic acid (216.3 g, 0.08 mole) was dissolved in 200 mL of water at 40° C. Solid sodium bicarbonate (54 g, 0.64 mole) was added slowly to raise the pH to 7.9. Sometimes, additional amounts of sodium bicarbonate was necessary to adjust the solution pH to 7.9. The solution was allowed to stir for 5 minutes. Excess KCl (134.4 g, 1.80 mole) was added to induce precipitation of the product as potassium salts. The white solid was collected by vacuum filtration and dried in a vacuum oven. The complex was characterized in D 2 O by 29 Si NMR with peak at 84.725.
Preparation of Potassium γ-decatungstosilicate, K 8 [γ-SiW 10 O 36 ] 7
Into a 125 mL Erlenmeyer flask equipped with a stir bar, K 8 [α-SiW 11 O 39 ] (5.0 g, 1.7 mole) was taken in 100 mL of water. The pH of this solution was adjusted to 9.1 by addition of 2M potassium carbonate using the Metrohm titrator. The solution was stirred for an additional 15 minutes while maintaining the pH at 9.1 with 2M potassium carbonate. Approximately 2 mL of base was used in the reaction. The potassium salt of the desired product was allowed to precipitate out by adding excess of potassium chloride (13.3 g, 0.18 mole). The white solid was collected by vacuum filtration and dried in a vacuum oven. It is characterized in D 2 O by 29 Si NMR with peak at 84.954.
Preparation of Sodium β-nonatungstosilicate, Na 10 [β-SiW 9 O 34 ] 7
Into a 250 mL beaker containing a stir bar, sodium metasilicate (3.26 g, 0.01 mole) was dissolved in 50 mL of water and sodium tungstate (30.03 g, 0.09 mole) added. The resulting solution had a pH of 12.6. To this solution, 18 mL of 6M HCl was added slowly using the Metrohm titrator over a period of about 30 minutes. The final solution contained some unreacted sodium silicate. It was filtered to give a clear solution which had a pH of about 8.4. The clear solution was allowed to crystallize in a refrigerator. The white crystals were filtered and dried in a vacuum oven. The complex was characterized in D 2 O by 29 Si NMR with peak at 83.814.
Preparation of K 8 [P 2 CuW 17 O 62 H 2 ]
K 10 [P 2 W 17 O 61 ].20H 2 O (8.7 g, 1.77×10 -3 mol) was dissolved in water (26 mL) at 70° C. Anhydrous CuSO 4 (0.35 g, 2.19×10 -3 mol) was then added to the mixture and stirred until dissolved. The mixture was then allowed to cool gradually to ambient temperature (25° C.). A green precipitate subsequently developed which was filtered and dried giving 6.9 g of a green crystalline solid. Recrystallization from water yielded 6.4 g of a green crystalline solid.
EXAMPLE 2
The polyoxometalates identified above were evaluated for their effectiveness in a Heterogeneous Protocol consisting of two stain monitors, strawberry (CS-18) and Tea (BC-1). Evaluations were performed at pH 6, 8 and 10 at 25° C., under a constant flow of oxygen with and without reducing agents (hydroxylamine and sodium ascorbate). Catalyst concentration was kept at 1×10 -5 M.
An Outline of the Essential Protocol Steps
a) Measure the initial reflectance of the swatches (R i ).
b) Saturate the wash solution with air.
c) Wash, rinse and dry the swatches.
d) Measure the final reflectance of the swatches (R f ).
All work was conducted in a Tergotometer with 2L stainless steel pots. The swatches were dried flat on a rack in a Kenmore dryer.
Each Tergotometer Pot was filled with 1 liter of milli-Q-water containing the carbonate buffer solution which was saturated for 15 minutes with air under agitation at 25° C. Tea stained (BC-1) swatches were washed for 30 minutes in the presence of Polyoxometalates and air. All swatches were rinsed twice for 3 minutes with agitation at 25° C. and dried flat on a rack in a Kenmore with soft heat for 30 minutes.
Bleaching Evaluation
To quantify the degree of stain removal, the reflectance of 4 stained swatches (4 per pot) were measured before and after washing using a Gardner reflectometer (Model #2000) set at 460*nm (*UV filter). The change in reflectance (ΔR) was determined by taking the difference of the swatch before and after each washing. The standard deviation (σ) and ΔΔR ave was assigned to each experimental group.
ΔR=R.sub.f -R.sub.i
R i =Initial reflectance of stained swatch before washing.
R f =Final reflectance of stained swatch after washing.
ΔR.sub.polyoxometallate system+control -ΔR.sub.control =ΔΔR - - - 1-3x - - - ΔΔR.sub.ave
ΔΔR ave =Represents the average bleaching by the polyoxometallate system.
N=number of measurements
TABLE 1__________________________________________________________________________Summary of the Heterogeneous ProtocolScreening Results of Selected POMs at pH = 6 Δ(ΔR)(Screening Conditions: air, 25° C., pH = 6, 1 Hour) Catalyst + Sodium Catalyst +Serial Catalyst Catalyst Alone Ascorbate.sup.a Hydroxylamine.sup.bNo. (1.0 × 10.sup.-5 M) BC-1 CS-18 BC-1 CS-18 BC-1 CS-18__________________________________________________________________________ 1 Na.sub.2 WO.sub.4 0.1 -0.1 -0.1 -0.5 -0.1 0.2 2 H.sub.4 SiW.sub.12 O.sub.40 0.1.4 0.3 0.1 0.2 0.5 3 H.sub.3 PW.sub.12 O.sub.40 0.10.2 0.1 0.5 0.1 0.1 4 α-K.sub.8 SiW.sub.11 O.sub.39 1.01 0.0 0.5 0.1 0.9 5 γ-K.sub.8 SiW.sub.10 O.sub.39 1.0.7 0.1 1.4 0.6 1.1 6 β-Na.sub.10 SiW.sub.9 O.sub.34 0.4 0.2 0.4 0.2 0.5 7 α-K.sub.7 PW.sub.11 O.sub.39 0.0.2 0.0 0.4 0.1 0.0 8 K.sub.7 SiVMnW.sub.10 O.sub.39 0.5 -0.2 0.3 0.7 0.9 9 K.sub.8 [P.sub.2 CuW.sub.17 O.sub.62 H.sub.2 ] 0.1 -0.2 1.8 2.6 -- --10.sup.c K.sub.8 [P.sub.2 CuW.sub.17 O.sub.62 H.sub.2 ] -- -- 0.1 -- --11 K.sub.10 [α-2-P.sub.2 W.sub.17 O.sub.61 ] 0.2 0.7 -0.1 0.6 -- --__________________________________________________________________________ .sup.a Used at 1.0 × 10.sup.-3 M .sup.b Used at 4.0 × 10.sup.-3 M .sup.c Air absent, argon atmosphere
TABLE 2__________________________________________________________________________Summary of the Heterogeneous ProtocolScreening Results of Selected POMS at pH = 8 Δ(ΔR) (Screening Conditions: air, 25° C., pH = 8, 1 Hour) Catalyst + Sodium Catalyst +Serial Catalyst Catalyst Alone Ascorbate.sup.a Hydroxylamine.sup.bNo. (1.0 × 10.sup.-5 M) BC-1 CS-18 BC-1 CS-1B BC-1 CS-18__________________________________________________________________________ 1 Na.sub.2 WO.sub.4 0.1 -0.2 -0.2 -0.3 0.3 0.4 2 H.sub.4 SiW.sub.12 O.sub.40 0.1 0.3 0.1 -0.1 -0.1 3 H.sub.3 PW.sub.12 O.sub.40 -0.1 0.0 0.0 0.0 0.1 4 α-K.sub.8 SiW.sub.11 O.sub.39 -0.1 0.0 0.3 0.1 0.3 5 γ-K.sub.8 SiW.sub.10 O.sub.39 0.1 0.0 0.3 0.4 0.3 6 β-Na.sub.10 SiW.sub.9 O.sub.34 0.0 0.0 0.2 0.0 0.2 7 α-K.sub.7 PW.sub.11 O.sub.39 -0.5 -0.2 0.1 -0.1 -0.2 8 K.sub.7 SiVMnW.sub.10 O.sub.39 0.4 -0.1 -0.2 0.2 -0.1 9 K.sub.8 [P.sub.2 CuW.sub.17 O.sub.62 H.sub.2 ] -1.1 -0.9 1.3 2.0 -- --10.sup.c K.sub.8 [P.sub.2 CuW.sub.17 O.sub.62 H.sub.2 ] -- -- -0.2 -0.8 -- --11 K.sub.10 [α-2-P.sub.2 W.sub.17 O.sub.61 ] 0.01 0.3 0.3 0.03 -- --12 Cs.sub.5 NbSiW.sub.11 O.sub.40 -- 0.4 -- 0.4 --13 K.sub.5 (NbO.sub.2)SiW.sub.11 O.sub.39 0.04 -- -0.2 -- 0.4 --14 (Me.sub.3 NH).sub.4 (NbO.sub.2) 0.4 -- 0.9 -- 0.3 -- PW.sub.11 O.sub.3915 K.sub.7 Mo.sub.2 VSiW.sub.9 O.sub.40 -- 0.01 -- 0.2 --16 K.sub.7 VMnSiW.sub.10 O.sub.39 -- -0.1 -- 0.2 --17 K.sub.7 VCoSiW.sub.10 O.sub.39 -- 0.1 -- 0.1 --__________________________________________________________________________ .sup.a Used at 1.0 × 10.sup.-3 M .sup.b Used at 4.0 × 10.sup.-3 M .sup.c Air absent, argon atmosphere
TABLE 3__________________________________________________________________________Summary of the Heterogeneous ProtocolScreening Results of Selected POMs at pH = 10 Δ(ΔR) (Screening Conditions: air, 25° C., pH = 10, 1 Hour) Catalyst + Sodium Catalyst +Serial Catalyst Catalyst Alone Ascorbate.sup.a Hydroxylamine.sup.bNo. (1.0 × 10.sup.-5 M) BC-1 CS-18 BC-1 CS-18 BC-1 CS-18__________________________________________________________________________ 1 Na.sub.2 WO.sub.4 0.2 0.1 -0.3 -0.4 0.2 0.2 2 H.sub.4 SiW.sub.12 O.sub.40 0.2.2 -0.3 0.1 -0.3 -0.9 3 H.sub.3 PW.sub.12 O.sub.40 -0.1 -0.1 -0.4 0.1 0.1 4 α-K.sub.8 SiW.sub.11 O.sub.39 -0.1 0.3 -0.4 0.0 -0.2 5 γ-K.sub.8 SiW.sub.10 O.sub.39 0.1 0.1 -0.4 0.1 0.1 6 β-Na.sub.10 SiW.sub.9 O.sub.34 0.0 -0.1 0.1 -0.1 -0.2 7 α-K.sub.7 PW.sub.11 O.sub.39 -0.1 -0.2 -0.2 0.1 0.0 8 K.sub.7 SiVMnW.sub.10 O.sub.39 0.1 0.1 0.1 2.5 9 K.sub.8 [P.sub.2 CuW.sub.17 O.sub.62 H.sub.2 ] -0.8 -1.1 -0.3 1.4 ---10.sup.cK.sub.8 [P.sub.2 CuW.sub.17 O.sub.62 H.sub.2 ] -- -0.5 -- --11 K.sub.10 [α-2-P.sub.2 W.sub.17 O.sub.61 ] 0.1 -0.1 0.2 0.4 --__________________________________________________________________________ .sup.a Used at 1.0 × 10.sup.-3 M .sup.b Used at 4.0 × 10.sup.-3 M .sup.c Air absent, argon atmosphere
The foregoing description and examples illustrate selected embodiments of the present invention. In light thereof variations and modifications will be suggested to one skilled in the art, all of which are within the spirit and purview of this invention. | A method for bleaching laundry and household surfaces is provided which iudes preparing a wash medium with a bleaching composition incorporating polyoxometalates and being free of any effective amount of a bleaching agent such as hydrogen peroxide, organic peracids, inorganic peracids, organic persalts, inorganic persalts, Caro's acid, Caroates and mixtures thereof. A second step involves contacting a stained substrate such as a fabric, kitchenware or a household hard surface for a time and in an amount sufficient to remove the stains. Air is employed as a primary source of oxygen atoms for bleaching. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an atomizer for various uses in which atomization of a liquid is required, such as combustors, internal combustion engines, humidifiers or other air conditioning equipments, sprayers for spraying agricultural chemicals, sprayers for paints, steel cooling systems and so forth. More particularly, the invention is concerned with an atomizer suited to the uses mentioned above and improved to avoid clogging of the atomizing injector while attaining high precision of atomization and peculiar atomizing characteristics, thereby to obviate various problems in the prior art.
2. Description of the Prior Art
Hitherto, atomizers having a single hole injector have been used in atomization systems of the impingement atomization type or in equipments such as, for example, apparatus for producing synthetic fibers, fire-fighting hose nozzles and so forth. The atomizer of the invention having a single hole injector is intended for uses in which atomization of liquids is required.
The single hole injector is formed by drilling, electric discharging or other known techniques. With these known techniques, however, it has been difficult to form a nozzle port having a diameter of less than 0.1 to 0.05 mm. In addition, it has been quite difficult to maintain the required precision in this size of nozzle port when the atomizer is mass-produced. Furthermore, an atomizer having an injector with a single nozzle port tends to become clogged with foreign matter and, hence, it is necessary to filtrate the liquid by a filter or strainer of fine mesh in order to trap the foreign matter. Besides, the single hole injector is not suitable for obtaining a high rate of atomization. For these reasons, linear spraying single nozzles have not been popular as compared with pressure swirling nozzles and air-blast nozzles.
SUMMARY OF THE INVENTION
Object of the Invention
Accordingly, an object of the invention is to provide an atomizer having an injector with fine nozzle ports finished with high precision, improved to suppress the tendency of clogging and to permit easy fabrication, thereby to obviate the above-described problems of the prior art.
Another object of the invention is to provide an atomizer suitable for use as liquid atomizer of the impingement atomization type.
To these ends, according to an aspect of the invention, there is provided an atomizer comprising a pair of plate members having flat peripheral regions; a disc having radial slits and clamped between the flat peripheral regions of the plate members so that the slits, in combination with the flat surfaces of the peripheral regions, constitute nozzle ports which provide communication between the space between the plate members and the exterior of the plate members; and a liquid supply tube communicated with the space between the plate members.
These and other objects, features and advantages of the invention will become clear from the following description of the preferred embodiments taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of an essential part of an embodiment of the atomizer in accordance with the invention;
FIG. 2 is a plan view of a disc which is a constituent of the atomizer shown in FIG. 1;
FIG. 3 is a sectional view of an essential part of another embodiment of the atomizer in accordance with the invention;
FIG. 4 is a plan view of another example of the disc; and
FIG. 5 is an illustration of an application of the atomizer of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the invention will be described hereinunder with reference to the accompanying drawings.
FIG. 1 shows in section an essential part of an embodiment of the atomizer in accordance with the invention. This atomizer has a pair of plate members 1 and 2 both of which are provided with recesses 3 and 3 and mirror-finished at their peripheral portions 4. These plate members 1 and 2 are assembled together with a disc or flat plate 5 clamped between the peripheral regions 4 thereof. The disc 5 is provided with radial slits 6 formed by etching. The space or cavity defined between the two plate members 1 and 2 is communicated with the exterior through these slits 6. Thus, each of the slits 6 constitutes a tetragonal nozzle port 9 the front and rear sides of which are defined by the flat surfaces of the peripheral regions 4 of the plate members 1 and 2.
A liquid supply tube 7 is connected to one end of the plate member 2. A liquid pressurized by a pump (not shown) is forcibly supplied into the space between the plate members 1 and 2, through the liquid supply tube 7 and the hole 10a of a bolt 10 screwed in the plate member 2, and is then introduced to the nozzle ports 9.
Liquid introduction passages 1' and 2' are formed between the bottom 8 of the recess 3 in the plate member 1 and the disc 5 and between the disc 5 and the bottom 8 of the recess 3 in the plate member 2, respectively. The liquid introduction passages 1' and 2' are communicated with the bore 10a in the bolt 10 mentioned before. Therefore, a part of the pressurized liquid is introduced into the liquid introduction passage 1' while the other part is introduced into the liquid introduction passage 2'. These parts of the pressurized liquid then merge toward each other at the upstream side of the nozzle ports 9 and then the liquid is discharged as liquid jets from the nozzle ports 9. It is possible to effect impingement atomization of the liquid for producing fine particles, by disposing impingement bodies ahead of the nozzle ports 9. Since the plate members 1, 2 and the disc 5 are integrally incorporated into one body by the bolt 10 extending through the disc 5, undesirable leakage of the pressurized liquid through portions other than the slits 6 is avoided advantageously.
The atomizer of the described embodiment offers the following advantages.
(1) The formation of the slits 6 in the disc 5 can be conducted without substantial difficulty. By using techniques suited to fine processing, e.g. etching, it is possible to form slits of a width less than 100 μ without substantial burrs or roughness, so that it is possible to obtain stable jets of liquid by avoiding any turbulence in the flow of liquid through the nozzle. In addition, the smooth surfaces of the slits 6 suppress the tendency of clogging with foreign matter.
(2) The peripheral regions 4 of the plate members 1 and 2 also can be processed easily without leaving any roughness in the surfaces of the slits 6 so that the above-mentioned advantages are not reduced.
(3) The passage of the pressurized liquid is branched into two narrow introduction passages 1' and 2' at the upstream side of the nozzle ports 9 and the pressurized liquid is introduced into the nozzle ports 9 through these narrow introduction passages 1' and 2'. In general, the Reynold's Number which is an index of turbulence of the flow is small when the passage is narrow. According to the invention, the passage upstream from the nozzle ports 9 is branched into two introduction passages each having a cross-sectional area which is about one-half of the passage upstream from the introduction passages and, hence, the Reynold's Number is reduced also almost by half, although the flow velocity is unchanged. In other words, the disc 5 serves to settle the flow of the liquid in the liquid introduction passages 1' and 2' so as to effectively prevent turbulence of the flow at the upstream side of the nozzle thereby eliminating any unfavorable effect on the liquid jet.
(4) In the atomizer produced by the conventional process, it is not possible to conduct a non-destructive inspection of the shape and size of the nozzle. According to the invention, however, the examination can be conducted without substantial difficulty simply by demounting the bolt 10.
(5) The nozzle ports can be formed easily in the form of radial slits in the disc 5, even when the atomizer is required to have a large number of nozzle ports.
(6) The disc 5 clamped between two plate members can be released as the screw 10 is loosened. In this state, the nozzle port 9 formed by each slit 6 is opened at both sides, so that it is possible to wash away foreign matter clogging the nozzle port 9 by a pressurized fluid stream. For the same reason, the atomizer can easily be disassembled for cleaning purposes.
FIG. 3 shows another embodiment of the atomizer in accordance with the invention. In this embodiment, a cylindrical base member 20 surrounds the liquid supply tube 7 and has one end 21 provided with an inwardly projecting annular flange 22. The upstream plate member 2, which has a bottom portion 11 of a diameter greater than that of the top portion thereof, is positioned adjacent the end 21 of the base member 20 to provide a space 23. In addition, the bolt 10 is provided with radial holes 10b communicating with the axial bore 10a. As the pressurized liquid is supplied through the axial bore 10a in the bolt 10, the pressure of the liquid is transmitted to the space 23 under the bottom portion 11 of the plate member 2 so that a force is exerted on the lower surface of the bottom portion of the plate member 2 to displace the latter upwardly while compressing a rubber ring 12. In consequence, the plate member 2 is pressed against the plate member 1 with the disc 5 clamped therebetween so as to form the nozzle ports 9. As the pressure of the liquid is decreased, the plate member 2 is moved downwardly by the force of the elastic rubber ring 12 to release the disc 5 from the clamping force. It will be seen that any foreign matter clogged in the nozzle ports 9 is carried away by the flow of the liquid each time the disc 5 is released from the clamping force. Namely, the opening of two sides of the tetragonal nozzle port 9 is made automatically through the change in the fluid pressure to permit the clogged foreign matter to be easily removed.
In the described embodiment, the slit 6 has a width d which is greater than the thickness t of the disc 5 so that the nozzle port 9 has a rectangular cross-sectional shape, as will be seen from FIGS. 1 and 2. The clamping and releasing of the disc 5 between two plate members are made at the longer sides, i.e. the two opposing sides in the thicknesswise direction of the disc 5, so that the clogged foreign matter can be removed easily.
FIG. 4 shows a modification of the disc 5 having slits 6 each of which diverges in the downstream direction as viewed in the direction of flow of the liquid. If the slit 6 has a constant width or converges in the downstream direction, foreign matter suspended by the liquid tend to be confined in the nozzle port 9. The foreign matter is then wedged into the nozzle port 9 to completely block the nozzle port 9 as the liquid pressure is applied thereto. To avoid this problem, it is preferred to make the slit 6 diverge in the downstream direction.
FIG. 5 schematically show an atomizer in accordance with the invention. The liquid is discharged in the form of a smooth jet from each nozzle port 9. The jet has a tetragonal cross-section at the outlet of the nozzle port 9 because the latter has a tetragonal shape. As the liquid jet flows away from the nozzle port 9, however, the tetragonal cross-section of the liquid jet tends to be changed into a circular cross-section due to the surface tension. This change generates a vigorous vibration in the liquid jet to break up the latter into droplets. This effect is achieveable also with a circular nozzle. An experiment was conducted by the present inventors, in which kerosene pressurized to 8 Kg/cm 2 was jetted from a circular nozzle port of 0.1 mm dia. It was confirmed that the smooth jet is broken up into a droplets jet after travelling about 100 mm from the nozzle port outlet. A similar experiment conducted with nozzle port having a tetragonal cross-section showed that the above-mentioned distance can be reduced to about 40 mm by using a nozzle port having a tetragonal shape. The droplets jet thus formed then impinges upon a deflector 13 so that each droplet forms a fine liquid film on the impinging surface and the liquid film is further broken up into fine particles.
It is quite advantageous that, according to the invention employing nozzle ports having a tetragonal cross-section, it is possible to remarkably reduce the size of the atomizer as a whole because the tetragonal cross-section of the nozzle port permits a reduction in the atomizing distance as above-mentioned, i.e. the distance between the nozzle and the deflector 13, as compared with the nozzle port having a circular cross-section. In addition, the invention permits a reduction in the size of the nozzle port which in turn affords a more fine atomization than by a conventional nozzle in the impingement atomization system. Furthermore, the invention offers various advantages such as prevention of clogging by foreign matter, ease of processing and so forth.
In the described embodiment, the deflectors are disposed in the region of the droplets, this is not exclusive and the deflectors may be disposed on a circle of a diameter smaller than that in the described embodiment to permit the liquid jet to impinge upon the deflectors before the jet is broken up into droplets.
Although the invention has been described in specific terms, it is to be noted here that the described embodiments are only for illustrating purpose and various changes and modifications may be imparted thereto without departing from the scope of the invention which is limited solely by the appended claims. | An atomizer for atomizing liquid, having a disc clamped between two plate members, the disc being provided with a plurality of radial slits which, in combination with the flat surfaces of peripheral regions of the plate members, constitute liquid atomizing nozzle ports having a tetragonal cross-section. This arrangement permits an easy formation of a plurality of nozzle ports and remarkably suppresses the tendency of clogging of the nozzle ports by foreign matter. In addition, it is possible to form precisely fine nozzle ports of a diameter which could never be attained by the conventional process. The tetragonal cross-section of the nozzle ports provide peculiar jetting characteristics for attaining good atomization of the liquid. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application is a continuation of pending U.S. patent application Ser. No. 12/411,453 filed Mar. 26, 2009, which is hereby incorporated by reference, in its entirety for any purpose.
BACKGROUND OF THE INVENTION
[0002] This relates generally to microelectronic memories.
[0003] Examples of microelectronic memories include flash memories, electrically erasable programmable read only memories, phase change memories, dynamic random access memories, and static random access memories. Each of these memories are generally accessed by a host device. In some cases, these memories may store information which is confidential or sensitive. Thus, it may be desirable to preclude unauthorized persons from accessing this information.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 is a system depiction of one embodiment; and
[0005] FIG. 2 is a flow chart for one embodiment.
DETAILED DESCRIPTION
[0006] Referring to FIG. 1 , in accordance with one embodiment, a host 10 may communicate with a microelectronic memory 12 . The microelectronic memory may be any type of memory, including as examples flash memories, electrically erasable programmable read only memories, phase change memories, dynamic random access memories, and static random access memories.
[0007] The host 10 may, for example, be a computer system or any processor-based system, including a personal computer, a laptop computer, a set top box, a camera, a graphics controller, a cell phone, a processor, or a controller, to mention a few examples. The memory 12 may be internal or may be external to the host 10 . The memory 12 may be accessed by the host 10 to perform operations such as accessing data stored in the memory array 16 , writing information to the memory array 16 , and configuring or programming the controller 14 to do certain functions under command of the host 10 , to mention a few examples.
[0008] In one embodiment, the controller 14 may access a password access register 18 and a password access block mapping storage 20 . As used herein, a “password” is any secret code, be it a number, a pattern, or text. The password access block mapping storage 20 may indicate which blocks within the memory array 16 may be password access controlled. While blocks are described herein, the present invention is not limited to any particular granularity of the memory array. The password access register 18 may provide information about the type of access control that may be implemented by password protection. For example, in some embodiments, the password access register 18 may include bits to indicate selected password access modes.
[0009] In one embodiment, the password access register may include 16 bits. One bit may indicate whether a given granularity of the memory array, such as a particular block, is protected from even being read. For example, the bit may be a 0 or 1 to indicate whether read protection is enabled or disabled, in one embodiment.
[0010] A second bit in the register 18 may indicate whether or not a given block (or other granularity of memory) is modify protected. In such case, the block may be prevented from being changed (i.e., written to). Again, the bit may be a 1 or a 0 to indicate that this capability is either enabled or disabled.
[0011] Still another bit may indicate whether each of a plurality of blocks is permanently protected against being rewritten. Again, the bit may be a 1 or a 0 to indicate whether the permanent protection is enabled or disabled.
[0012] Still another bit may indicate whether a password is needed to update the read block lock map in mapping storage 20 . Still another bit may indicate whether a password is needed to update the modify block lock map in mapping storage 20 . Finally, still another bit may indicate whether a password is needed to update the permanent block lock map in mapping storage 20 .
[0013] An additional two bits may indicate the password size. The password size may be 64 bits, 128 bits, or 256 bits, in some embodiments. However, different numbers of bits implementing different access controls may be used in other embodiments.
[0014] In password access read blocking, reading is prevented. In modify blocking, modifying of the stored information may be prevented, even if reading is otherwise allowed. A permanent block lock map indication indicates that the given block is permanently locked and cannot ever be modified. It may or may not be readable.
[0015] The password access block mapping storage 20 may indicate to the controller 14 which blocks (or other memory granularities) are password accessible. Once it is known that a given block (or other granularity) must be accessed with a password, the password access register 18 may be accessed to determine the type of access protection that is involved. In one embodiment, the register 18 and storage 20 may be combined in one unit.
[0016] Thus, in some embodiments, the actual data stored in the memory array may be protected with one or more passwords. Only those users who have the correct password can access the protected data. In some embodiments, even though a given block is password protected, it may be read freely, but may not be modified. Thus, the information may be read, but, in some cases, not modified. In other cases, it cannot even be read without a password.
[0017] Thus, in order to program the password protection status, commands may be provided by the host to the controller. A plurality of commands may be provided that are distinguishable, one for each of the different modes. The different password modes may include, in one embodiment, no protection enabled; permanent protection enabled; modify protection enabled; and read protection enabled; permanent protect and modify protect, both enabled; permanent protect only enabled; modify protect and read protect enabled; and modify protect only enabled. Those skilled in the art would appreciate a number of other programmable password protection modes.
[0018] Referring to FIG. 2 , in accordance with one embodiment of the present invention, a sequence of operations may be implemented in hardware or software. In the software embodiment, the sequence may be implemented in a computer readable medium, such as the memory array 16 , or a memory on board the controller 14 , to mention two examples. In still other embodiments, the sequence may be implemented by the host 10 .
[0019] Initially, a check at diamond 24 indicates whether or not the host 10 is attempting to access a granularity, such as a block, within the memory array 16 . If so, a check of the mapping storage 20 , at block 26 , determines whether or not the access granularity, such as a block, is password protected. If the block is locked (i.e. password protected), as determined in diamond 28 , a check of the password access register 18 determines the type of access conditions that are applicable, as indicated in block 30 . The conditions may then be implemented, as indicated in block 32 . These conditions may involve requesting a password via a user interface or waiting for receipt of the password for a given period of time, as two examples. When the password is received, as indicated at block 34 , a comparison of the received password to a stored password is undertaken, as indicated in diamond 36 . If there is a match, the access may be granted or the requested operation, such as programming the protected password mode, may be implemented.
[0020] The password may be stored in the sequence where the host programs the controller 14 with the desired access control mode, together with a password for each mode. The password may be reprogrammably stored on board the controller 24 in one embodiment.
[0021] In some embodiments, the password status may be implemented during the manufacturing process. In other embodiments, it may be programmed by appropriate commands by the first purchaser from the manufacturer. In some cases, the first purchaser is not the end user, but may set up the access passwords as desired. And, in some cases, the access limitations may be applied by the end user. Thus, different parties may be given the commands to program the desired level of password security.
[0022] References throughout this specification to “one embodiment” or “an embodiment” mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one implementation encompassed within the present invention. Thus, appearances of the phrase “one embodiment” or “in an embodiment” are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be instituted in other suitable forms other than the particular embodiment illustrated and all such forms may be encompassed within the claims of the present application.
[0023] While the present invention has been described with respect to a limited number of embodiments, those skilled in the art will appreciate numerous modifications and variations therefrom. It is intended that the appended claims cover all such modifications and variations as fall within the true spirit and scope of this present invention. | A microelectronic memory may be password access protected. A controller may maintain a register with requirements for accessing particular memory locations to initiate a security protocol. A mapping may correlate which regions within a memory array are password protected. Thus, a controller can use a register and the mapping to determine whether a particular granularity of memory is password protected, what the protection is, and what protection should be implemented. As a result, in some embodiments, a programmable password protection scheme may be utilized to control a variety of different types of accesses to particular regions of a memory array. | 6 |
This application is a continuation of application Ser. No. 07/392,738, filed Aug. 11, 1989, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a light-sensitive silver halide photographic material which gives images of high contrast, more particularly to improvement of trouble generated in high contrasting technique with a hydrazide compound.
In recent years, in the field of printing photomechanical process, color formation and complication of printing are under remarkable progress. Accordingly, improvement of quality and stability of quality for light-sensitive silver halide photographic material for printing (hereinafter called printing sensitive material) which is the intermediate medium for printing have been increasingly demanded year by year. In the prior art, printing sensitive material has been generally endowed with the so called "lith development" processing aptitude for accomplishing high quality. However, in "lith development", it is impossible in mechanism to contain sulfite ion which is the preservative at high concentration in the development processing solution, and therefore stability of the developer is very poor, as is well known to those skilled in the art.
As the technique for cancelling instability of "lith development", and obtaining images of high contrast comparable to the "lith development", some attempts can be found in disclosures of patent literatures. For example, techniques for obtaining tone hardened images by use of hydrazide compounds are disclosed in Japanese Unexamined Patent Publications Nos. 16623/1978, 20921/1978, 20922/1978, 49429/1978, 66731/1978, 66732/1978, 77616/1978, 84714/1978, 137133/1978, 37732/1979, 40629/1979, 52050/1980, 90940/1980, 67843/1981 and others. In the processing method in the image forming method by use of these hydrazide compounds, in order to obtaining an image of high contrast, it is required that the pH value of the developer containing the hydrazide compound or pH value of the processing developer for the light-sensitive photographic material containing the hydrazide compound should be at high level, and such high pH value disadvantageously lowers the effective life of the developer.
In contrast, in Japanese Unexamined Patent Publication No. 106244/1981, it is described that an image of high contrast can be formed at relatively lower pH (11-11.5) by having a hydrazide compound and a development promoting amount of an amino compound contained during formation of image.
The image forming method by use of these hydrazide compounds can obtain images of very high contrast. Generally speaking, development processing solution may suffer from fog generation, etc. undesirable in photographic performance when no adequate development supplementing agent is supplemented, but in the method by use of hydrazide, even when the fatigue degree of the development processing solution is not so great, generation of black dots like black sesame (hereinafter called pepper fog) is seen at the unexposed portion, for example, between the dots during halftoning by use of a contact screen in printing sensitive material, whereby a trouble may be caused to occur which can be a vital defect in commercial value. In Japanese Unexamined Patent Publications Nos. 16623/1978 and 20921/1978 as previously mentioned, generation of fog containing pepper fog as mentioned above is inhibited by incorporating benzotriazole which is an inhibitor in the silver halide photographic emulsion, but its effect is not sufficient, and high contrast may be sometimes impaired, and it can hardly be said to be a completed technique.
The present inventors have studied intensively and consequently have developed a light-sensitive silver halide photographic material which does not impair high contrast while inhibiting the fog including pepper fog which is the drawback of the tone hardening technique by use of a hydrazide compound.
SUMMARY OF THE INVENTION
A first object of the present invention is to provide a light-sensitive silver halide photographic material capable of forming a stable image of high contrast by use of a hydrazide compound. A second object of the present invention is to provide a light-sensitive silver halide photographic material with high contrast without generation of fog including pepper fog.
The above objects of the present invention can be accomplished by a light-sensitive silver halide photographic material having a hydrophilic colloid layer containing at least one layer of a light-sensitive silver halide emulsion layer provided on a support, wherein a hydrazide derivative is contained in said light-sensitive silver halide emulsion layer, and the above hydrophilic colloid layer contains at least one of the compounds represented by Formulae [II] and [III] shown below: ##STR3## wherein R 1 represents hydrogen atom, a straight or branched alkyl group, a cyclic alkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, an alkylamide group, an arylamide group, an alkylthioamide group, an arylthioamide group, an alkylsulfonamide group or an arylsulfonamide group, R 2 and R 3 each represent hydrogen atom, a halogen atom, an alkyl group, a cyclic alkyl group, an aryl group, a cyano group, an alkylthio group, an arylthio group, an arylsulfoxide group or an alkylsulfonyl group; with proviso that the above alkyl group, the cylic alkyl group, the alkenyl group, aralkyl group, aryl group and heterocyclic group may have substituent, ##STR4## wherein R 1 represents hydrogen atom, a lower alkyl group or a hydroxymethyl group, and R 2 represents hydrogen atom or a lower alkyl group.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following, the constitution of the present invention is to be described in detail. The hydrazide derivative to be used in the present invention may include the compounds represented by the following formulae [I -a], [I - b] and [I - c]. ##STR5## wherein R 1 and R 2 each represent an aryl group or a heterocyclic group, R represents a divalent organic linking group, n is 0 to 6, m is 0 or 1, and when n is 2 or more, respective R's may be either the same or different). ##STR6## wherein R 21 represents an aliphatic group, an aromatic group or a heterocyclic group, R 22 represents hydrogen atom, an alkoxy group which may be substituted, a heterocyclic oxy group, an amino group or an aryloxy group, P 1 and P 2 each represent hydrogen atom, an acyl group or a sulfinic acid group. ##STR7## wherein Ar represents an aryl group containing at least one of diffusion resistant group or silver halide adsorption promoting group, and R 31 represents a substituted alkyl group.
In the following, Formulae [I - a], [I -b] and [I - c] are to be described in more detail below. ##STR8##
In the formula, R 1 and R 2 each represent an aryl group or a heterocyclic group, R represents a divalent organic linking group, and n represents 0 to 6 and m represents 0 or 1.
Here, the aryl group represented by R 1 and R 2 may include phenyl group, naphthyl group, and the heterocyclic group represented by R 1 and R 2 may include pyridyl group, benzothiazolyl group, quinolyl group, thienyl group, etc., but R 1 and R 2 may be preferably aryl groups. The aryl group or heterocyclic group represented by R 1 and R 2 can introduce various substituents therein. Examples of substituents may include halogen atoms (e.g. chlorine, fluorine, etc.) alkyl groups (e.g. methyl, ethyl, dodecyl, etc.), alkoxy groups (e.g. methoxy, ethoxy, isopropoxy, butoxy, octyloxy, dodecyloxy, etc.), acylamino groups (e.g. acetylamino, pivalylamino, benzoylamino, tetradecanoylamino, α-(2,4-di-t-amylphenoxy) butyrylamino, etc.), sulfonylamino groups (e.g. methanesulfonylamino, butanesulfonylamino, dodecanesulfonylamino, benzenesulfonylamino, etc.), urea groups (e.g. phenylurea, ethylurea, etc.), thiourea groups (e.g. phenylthiourea, ethylthiourea, etc.), hydroxy group, amino group, alkylamino groups (e.g. methylamino, dimethylamino, etc.), carboxy group, alkoxycarbonyl groups (e.g. ethoxycarbonyl), carbamoyl group, sulfo group and so on. Examples of the divalent organic linking group represented by R may include alkylene groups (e.g. methylene, ethylene, trimethylene, tetramethylene, etc.), arylene groups (e.g. phenylene, naphthylene, etc.), aralkylene groups, etc., and the alkylene group may contain oxy group, thio group,seleno group, carbonyl group, ##STR9## (R 3 represents hydrogen atom, an alkyl group, an aryl group), sulfonyl group, etc. in the bond. Into the group represented by R can be introduced various substituents.
Examples of substituents may include --CONHNHR 4 (R 4 has the same meaning as R 1 and R 2 as described above), alkyl groups, alkoxy groups, halogen atoms, hydroxy group, carboxy group, acyl groups, aryl groups, etc.
R may be preferably a alkylene group.
Of the compounds represented by Formula [I - a], preferable are compounds wherein R 1 and R 2 are substituted or unsubstituted phenyl groups, n=m=1 and R represents an alkylene group.
Representative compounds represented by the above Formula [I - a] are shown below. ##STR10##
In the following, Formula [I - b] is to be described. ##STR11## The aliphatic group represented by R 21 may be preferably one having 6 or more carbon atoms, particularly a straight, branched or cyclic alkyl group having 8 to 50 carbon atoms. Here, the branched alkyl group may be cyclized so as to form a saturated hetero ring containing one or more hetero atoms. The alkyl group may have substituent such as aryl group, alkoxy group, sulfoxy group, etc.
The aromatic group represented by R 21 is a monocyclic or bicyclic aryl group or unsaturated heterocyclic group. Here, the unsaturated heterocyclic group may be condensed with the monocyclic or bicyclic group to form a heteroaryl group.
For example, there may be included benzene ring, naphthalene ring, pyridine ring, pyrimidine group, imidazole ring, pyrazole ring, quinoline ring, isoquinoline ring, benzimidazole ring, thiazole ring, benzothiazole ring, etc., but amount them those containing benzene ring are preferred.
As R 22 , particularly preferred is an aryl group.
The aryl group or unsaturated heterocyclic group represented by R 21 may be substituted, and representative substituents may include straight, branched or cyclic alkyl groups (preferably monocyclic or bicyclic ones with an alkyl moiety having 1 to 20 carbon atoms), alkoxy groups (having preferably 1 to 20 carbon atoms), substituted amino groups (preferably amino groups substituted with alkyl groups having 1 to 20 carbon atoms), acylamino groups (having preferably 2 to 30 carbon atoms), sulfonamide groups (having preferably 1 to 30 carbon atoms), ureido groups (having preferably 1 to 30 carbon atoms) and others.
Of the groups represented by R 22 in the formula [I - b], the alkoxy group which may be substituted may have 1 to 20 carbon atoms and may be substituted with halogen atoms, aryl groups, etc.
Of the groups represented by R 22 in the formula [I - b], the aryloxy group or the heterocyclic oxy group which may be also substituted may be preferably monocyclic, and the substituent may include halogen atoms, alkyl groups, alkoxy group, cyano group, etc.
Of the groups represented by R 22 , preferable are alkoxy groups or amino groups which may be also substituted.
In the case of an amino group, A 1 and A 2 in the group ##STR12## may be an alkyl group, alkoxy group which may be substituted, or a cyclic structure containing --O--, --S--, --N-- group bond. However, R 22 cannot be hydrazino group.
R 21 or R 22 in Formula [I - b] may be one having a ballast group conventionally used in the immobile additive for photography such as coupler, etc. incorporated therein. The ballast group is a group having 8 or more carbon atoms relatively inert to photographic characteristic, and can be chosen from, for example, alkyl groups, alkoxy groups, phenyl groups, alkylphenyl groups, phenoxy groups, alkylphenoxy groups, etc.
R 21 or R 22 in Formula [I - b] may be also one having a group for strengthening adsorption to the surface of silver halide grains incorporated therein. As such adsorptive groups, there may be included the groups as disclosed in U.S. Pat. No. 4,355,105 such as thiourea group, heterocyclic thioamide group, mercaptoheterocyclic group, triazole group, etc. Among the compounds represented by the group [I - b], the compounds represented by Formula [I - b - a] are particularly preferable. ##STR13## In the Formula [I - b - a],
R 23 and R 24 each represent hydrogen atom, an alkyl group which may be substituted (e.g. methyl, ethyl, butyl, dodecyl, 2-hydroxypropyl, 2-cyanoethyl, 2-chloroethyl group), a phenyl, naphthyl, cyclohexyl, pyridyl, pyrrolidyl group which may be substituted (e.g. phenyl, p-methylphenyl, naphthyl, α-hydroxy-naphthyl, cyclohexyl, p-methylcyclohexyl, pyridyl, 4-propyl-2-pyridyl, pyrrolidyl, 4-methyl-2-pyrrolidyl group);
R 25 represents hydrogen atom or a benzyl, alkoxy and alkyl group which may be substituted (e.g. benzyl, p-methylbenzyl, methoxy, ethoxy, ethyl, butyl group);
R 26 and R 27 each represent a divalent aromatic group (e.g. phenylene or naphthylene group), Y represents sulfur atoms or oxygen atom, L represents a divalent linking group (e.g. --SO 2 CH 2 CH 2 NH--SO 2 NH--, --OCH 2 SO 2 NH--, --O--, --CH═N--);
R 28 represents --NR'R" or --OR 29 ;
R', R" and R 29 each represent hydrogen atom, an alkyl group which may be substituted (e.g. methyl, ethyl, dodecyl group), a phenyl group which may be substituted (e.g. phenyl, p-methylphenyl, p-methoxyphenyl group) or a naphthyl group which may be substituted (e.g. α-naphthyl group, β-naphthyl group), m, n represent 0 or 1, and when
R 28 represents OR 29 , Y should preferably represent sulfur atom.
Represenatative compounds represented by the above Formulae [I - b] and [I - b - a] are shown below.
Specific compounds of Formula [I-b]: ##STR14##
Of the above specific compounds, by taking examples of the compounds I - b - 45 and I - b - 47, their synthetic methods are shown below.
Synthesis of Compound I - b - 45 ##STR15##
A mixture of 153 g of 4-nitrophenylhydrazide and 500 ml of diethyloxalate is refluxed for one hour. While the reaction is proceeded, ethanol is removed and finally the mixture is cooled to precipitate crystals. After filtration, the product is washed several times with petroleum ether and recrystallized. Then, 50 g of the crystals (A) obtained are dissolved by heating in 1000 ml of methanol, and reduced in a H 2 atmosphere pressurized at 50 psi in the presence of Pd/C (palladium-carbon) catalyst to obtain the compound (B).
To a solution of 22 g of the compound (B) dissolved in 200 ml of acetonitrile and 16 g of pyridine is added an acetonitrile solution containing 24 g of the compound (C) at room temperature. After the insolubles are filtered off, the filtrate is concentrated and purified by recrystallization to obtain 31 g of the compound (D).
Thirty (30) g of the compound (D) is hydrogenated similarly as described above to obtain 20 g of the compound (E).
To a solution of 10 g of the compound (E) dissolved in 100 ml of acetonitrile is added 3.0 g of ethylisothio-cyanate, and the mixture is refluxed for one hour. After evaporation of the solvent, the residue is purified by recrystallization to obtain 7.0 g of the compound (F). To a solution of 5.0 g of the compound (F) dissolved in 50 ml of methanol is added methylamine (8 ml of aqueous 40% solution), followed by stirring. After concentrating slightly methanol, the precipitated solid is taken out and purified by recrystallization to obtain Compound I - b - 45.
Synthesis of Compound I - b - 47 ##STR16##
Into a stirred solution of 22 g of the compound (B) dissolved in 200 ml of pyridine, 22 g of p-nitrobenzenesulfonyl chloride is added. The reaction mixture is poured into water, and the post-precipitated solid is taken out to obtain the compound (C). From the compound (C), according to the same reactions as in the case of Compound I - b - 45 following the synthesis scheme, Compound I - b - 47 is obtained.
Next, Formula [I - c] is to be described. ##STR17##
In Formula [I - c], Ar represents an aryl group containing at least one of diffusion resistant groups or silver halide adsorption promoting groups, and as the diffusion resistant group, a ballast group conventionally used in immobile additives for photography such as coupler, etc. is preferable. The ballast group is a group having 8 or more carbon atoms relatively inert to photographic characteristic, and can be chosen from, for example, alkyl groups, alkoxy groups, phenyl groups, alkylphenyl groups, phenoxy groups, alkylphenoxy groups, etc.
As the silver halide adsorption promoting group, there may be included the groups as disclosed in U.S. Pat. No. 4,385,108 such as thiourea group, thiourethane group, heterocyclic thioamide group, mercaptoheterocyclic group, triazole group, etc.
R 31 represents a substituted alkyl group, and the alkyl group may be a straight, branched or cyclic alkyl group, including methyl, ethyl, propyl, butyl, isopropyl, pentyl, cyclohexyl and the like.
As the substituent to be introduced into these alkyl group, there may be included groups of alkoxy (e.g. methoxy, ethoxy), aryloxy (e.g. phenoxy, p-chlorophenoxy), heterocyclic oxy (e.g. pyridyloxy), mercapto, alkylthio (e.g. methylthio, ethylthio), arylthio (e.g. phenylthio, p-chlorophenylthio), heterocyclic thio (e.g. pyridylthio, pyrimidylthio, thiadiazolylthio), alkylsulfonyl (e.g. methanesulfonyl, butanesulfonyl), arylsulfonyl (e.g. benzenesulfonyl), heterocyclic sulfonyl (e.g. pyridylsulfonyl, morpholinosulfonyl), acyl (e.g. acetyl, benzoyl), cyano, chloro, bromo, alkoxycarbonyl (e.g. ethoxycarbonyl, methoxycarbonyl), aryloxycarbonyl (e.g. phenoxycarbonyl), carboxy, carbamoyl, alkylcarbamoyl (e.g. N-methylcarbamoyl, N,N-dimethylcarbamoyl), arylcarbamoyl (e.g. N-phenylcarbamoyl), amino, alkylamino (e.g. methylamino, N,N-dimethylamino), arylamino (e.g. phenylamino, naphthylamino), acylamino (e.g. acetylamino, benzoylamino), alkoxycarbonylamino (e.g. ethoxycarbonylamino), aryloxycarbonylamino (e.g. phenoxycarbonylamino), acyloxy (e.g. acetyloxy, benzoyloxy), alkylaminocarbonyloxy (e.g. methylaminocarbonyloxy), arylaminocarbonyloxy (e.g. phenylaminocarbonyloxy), sulfo, sulfamoyl, alkylsulfamoyl (e.g. methylsulfamoyl), arylsulfamoyl (e.g. phenylsulfamoyl), etc.
The hydrogen atom of hydrazide may be also substituted with a substituent such as sulfonyl group (e.g. methanesulfonyl, toluenesulfonyl), acyl group (e.g. acetyl, trifluoroacetyl), oxalyl group (e.g. ethoxalyl), etc.
Representative compounds represented by the above Formula [I - c] are shown below. ##STR18##
Next, a synthesis example of Compound I - c - 5 is described.
Synthesis of Compound I - c - 5 ##STR19##
According to the procedure similar to the synthetic method of Compound I - b - 45, Compound I - c - 5 is obtained.
The amount of the compounds of Formulae [I - a], [I - b] and [I - c] contained in the light-sensitive silver halide material of the present invention should be preferably within the range of from 5×10 -7 to 5×10 -1 mol, more preferably 1×10 -5 to 1×10 -2 mol, per mol of silver halide contained in the light-sensitive silver halide photographic material.
Next, Formula [II] of the present invention is to be described. ##STR20##
In Formula, R 1 represents hydrogen atom, a straight or branched alkyl group, a cyclic alkyl group, an alkenyl group, an aralykyl group, an aryl group, a heterocyclic group, an alkylamino group, an arylamide groups, an alkylthioamide group, an arylthioamide group, an alkylsulfoamide group, an arylsulfoamide group; R 2 , R 3 each represent hydrogen atom, a halogen atom, an alkyl group, a cyclic alkyl group, an aryl group, a cyano group, an alkylthio group, an arylthio group, an alkylsulfoxide group, an alkylsulfonyl group, a heterocyclic group. However, the above alkyl group, cyclic alkyl group, alkenyl group, heteocyclic group, aralkyl group and aryl group may have substituents.
In R 1 in Formula [II], the alkyl group and the alkenyl group may have 1 to 36, more preferably 1 to 18 carbon atoms. The cyclic alkyl group may have 3 to 12, more preferably 3 to 6 carbon atoms. These alkyl groups, alkenyl groups, cyclic alkyl groups, aralkyl groups, aryl groups, heterocyclic groups may have substituents, and the substituent may be chosen from halogen atom, nitro, cyano, thiocyano, aryl, alkoxy, aryloxy, carboxy, sulfoxy, alkylcarbonyl, arylcarbonyl, alkoxycarbonyl, aryloxycarbonyl, sulfo, acyloxy, sufamoyl, carbamoyl, acylamino, diacylamino, ureido, thioureido, urethane, thiourethane, sulfonamide, heterocyclic group, arylsulfonyloxy, alkylsulfonyloxy, arylsulfonyl, alkylsulfonyl group, arylthio, alkylthio, alkylsulfinyl, arylsulfinyl, alkylamino, dialkylamino, N-alkylanilino, N-arylanilino, N-acylamino, hydroxy and mercapto group, etc.
In R 2 , R 3 in Formula [II], the alkyl group may have 1 to 18, more preferably 1 to 9 carbon atoms. The cyclic alkyl group may have 3 to 12, more preferably 3 to 6 carbon atoms. These alkyl groups, cyclic alkyl groups and aryl groups may have substituents, and the substituent may include halogen atom, nitro group, sulfone group, aryl group, hydroxy group, etc.
Representative examples of the compounds represented by the above Formula [II] (hereinafter called compounds of the present invention) are shown below, but the compounds of the present invention are not limited to these.
Exemplary compounds
2-methyl-3-isothiazolone;
2-(N-methylcarbamoyl)-3-isothiazolone;
5-methyl-2-(N-methylcarbamoyl)-3-isothiazolone;
2-(N-methylthiocarbamoyl)-3-isothiazolone;
4-bromo-5-methyl-2-(N-methylcarbamoyl)-3-isothiazolone;
4-cyano-5-methylthio-2-(N-methylcarbamoyl)-3-isothiazolone;
4-cyano-5-methylsulfinyl-2-(N-methylcarbamoyl)-3-isothiazolone;
4-cyano-5-methylsulfonyl-2-(N-methylcarbamoyl)-3-isothiazolone;
2-(N-n-butylcarbamoyl)-3-isothiazolone;
2-(N-t-octylcarbamoyl)-3-isothiazolone;
3-methyl-2-(N-phenylcarbamoyl)-3-isothiazolone;
4-cyano-5-methylthio-2-(N-phenylcarbamoyl)-3-isothiazolone;
4-bromo-5-methyl-2-(N-3-chlorophenylcarbamoyl)-3-isothiazolone;
5-bromomethyl-2-(N-3-chlorophenylcarbamoyl)-3-isothiazolone;
5-methyl-2-(N-3-chlorophenylcarbamoyl)-3-isothiazolone;
4-cyano-5-methylthio-2-(N-3-chlorophenylcarbamoyl)-3-isothiazolone;
2-(N-3-chlorophenylcarbamoyl)-3-isothiazolone;
5-methyl-2-(N-2-chlorophenylcarbamoyl)-3-isothiazolone;
5-bromomethyl-3-(N-2-chlorophenylcarbamoyl)-3-isothiazolone;
4-bromo-5-methyl-2-(N-3,4-dichlorophenylcarbamoyl)-3-isothiazolone;
5-methyl-2-(N-3,4-dichlorophenylcarbamoyl)-3-isothiazolone;
4-cyano-5-methylthio-2-(N-3,4-dichlorophenylcarbamoyl)-3-isothiazolone;
5-methyl-2-(N-4-tosylcarbamoyl)-3-isothiazolone;
4-cyano-5-methylthio-2-(N-4-tosylcarbamoyl)-3-isothiazolone;
4-bromo-5-methyl-2-(N-4-tosylcarbamoyl)-3-isothiazolone;
2-(N-n-propylcarbamoyl)-3-isothiazolone;
2-(N-ethylcarbamoyl)-3-isothiazolone;
2-(N-i-propylcarbamoyl)-3-isothiazolone;
4-bromo-2-(N-methylcarbamoyl)-3-isothiazolone;
2-(N-4-methoxyphenylcarbamoyl)-3-isothiazolone;
2-(N-2-methoxyphenylcarbamoyl)-3-isothiazolone;
2-(N-3-nitrophenylcarbamoyl)-3-isothiazolone;
2-(N-3,4-dichlorophenylcarbamoyl)-3-isothiazolone;
2-(N-n-dodecylcarbamoyl)-3-isothiazolone;
2-(N-2,5-dichlorophenylcarbamoyl)-3-isothiazolone;
2-(N-carboethoxymethylcarbamoyl)-3-isothiazolone;
2-(N-4-nitrophenylcarbamoyl)-3-isothiazolone;
5-methyl-2-(N-ethylcarbamoyl)-3-isothiazolone;
5-methyl-2-(N-ethylthiocarbamoyl)-3-isothiazolone;
5-chloro-2-(N-ethylcarbamoyl)-3-isothiazolone;
2-n-propyl-3-isothiazolone;
2-t-butyl-3-isothiazolone;
2-n-butyl-3-isothiazolone;
2-cyclohexyl-3-isothiazolone;
2-t-octyl-3-isothiazolone;
2-benzyloxy-3-isothiazolone;
5-chloro-2-methyl-3-isothiazolone;
5-chloro-2-benzyl-3-isothiazolone;
4,5-dichloro-2-methyl-3-isothizaolone;
2,4-dimethyl-3-isothizaolone;
4-methyl-2-(3,4-dichlorophenyl)-3-isothiazolone;
2-(3,4-dichlorophenyl)-3-isothiazolone;
4,5-dichloro-2-benzyl-3-isothiazolone;
4-bromo-5-chloro-2-methyl-3-isothiazolone;
4-bromo-2-methyl-3-isothiazolone;
2-hydroxymethyl-3-isothiazolone;
2-(α,β-diethylaminoethyl)-3-isothiazolone;
2-n-propyl-3-isothiazolone hydrochloride;
5-chloro-2-methyl-3-isothiazolone hydrochloride;
2-ethyl-3-isothiazolone hydrochloride;
2-methyl-3-isothiazolone hydrochloride;
2-benzyl-3-isothiazolone hydrochloride;
2-n-dodecyl-3-isothiazolone;
2-n-tetradecyl-3-isothiazolone;
2-(4-chlorobenzyl)-3-isothiazolone;
2-(2-chlorobenzyl)-3-isothiazolone;
2-(2,4-dichlorobenzyl)-3-isothiazolone;
2-(3,4-dichlorobenzyl)-3-isothiazolone;
2-(4-methoxybenzyl)-3-isothiazolone;
2-(4-methylbenzyl)-3-isothiazolone;
2-(2-ethoxyhexyl)-3-isothiazolone;
2-(2-phenylethyl)-3-isothiazolone;
2-(2-phenylethyl)-4-chloro-3-isothiazolone;
2-(1-phenylethyl)-3-isothiazolone;
2-n-decyl-3-isothiazolone;
2-n-octyl-3-isothiazolone;
2-t-octyl-4-chloro-3-isothiazolone;
2-t-octyl-4-bromo-3-isothiazolone;
2-n-nonyl-3-isothiazolone;
2-n-octyl-5-chloro-3-isothiazolone;
2-(4-nitrophenyl)-3-isothiazolone;
2-(carboethoxyphenyl)-3-isothiazolone;
5-chloro-2-methyl-3-isothiazolone monochloroacetate;
4,5-dichloro-2-methyl-3-isothiazolone monochloroacetate;
2-ethyl-3-isothiazolone monochloroacetate;
2-n-propyl-3-isothiazolone monochloroacetate;
2-benzyl-3-isothiazolone monochloroacetate.
With respect to these exemplary compounds, are described in French Patent 1,555,416, etc. about their synthetic methods and application examples to other fields.
Next, the compound represented by Formula [III] is to be described. ##STR21## wherein R 1 represents hydrogen, a lower alkyl group or hydroxymethyl group, and R 2 represents hydrogen or a lower alkyl group.
In the above Formula, R 1 represents hydrogen, a lower alkyl group or hydroxymethyl group, R 2 represents hydrogen or a lower alkyl group, and as the lower alkyl group, one having 1 to 5 carbon atoms, particularly 1 carbon atom, is preferred.
SPECIFIC EXAMPLE ##STR22##
These compounds can be synthesized by referring to the following literatures, and also a part of them are commercially available from Mitsubishi Sekiyu K.K.
(1) Henry. Ecueil des travaux chimiques des Rays-Bas. 16 251
(2) Maas. Chemisches Zentralblatt. 1899 I 179
(3) E. Schmidt. Berichte der Deutchen Chemischen Gesellschaft. 52 387
(4) E. Schmidt. ibid. 55 317
(5) Henry. Chemisches Zentralblatt 1897 11 338
The compound represented by Formulae [II] or [III] may be used in an amount preferably within the range of 1×10 -3 to 10% by weight, preferably 1×10 -3 to 3% by weight, more preferably 5×10 -3 to 3% by weight, based on the hydrophilic colloid. However, the above range may be more or less varied depending on the kind of the light-sensitive silver halide photograpic material, the layer into which it is added, the coating method, etc., as a matter of course.
In one aspect of the invention, a light-sensitive silver halide photographic material according to the invention may contain a hydrazide derivative in an amount of 1×10 -5 to 1×10 -2 mol per mol of silver halide, and at least one member selected from the group of 2-methyl-3-isothiazolone, 5-chloro-2-methyl-3-isothiazolone, 4,5-dichloro-2-methyl-3-isothiazolone and a compound represented by the formula III-1: ##STR23## in an amount of 1×10 -3 to 3% by weight based on the hydrophilic colloid.
The compound of the present invention may be dissolved in a solvent which has no deleterious influence on photographic performance, chosen from water and organic solvents such as methanol, isopropanol, acetone, etc. and added as the solution into the hydrophilic colloid, or coated on the protective layer or incorporated by dipping into a sterilizing agent solution. Alternatively, there may be also employed the method in which the compound is dissolved in a high boiling solvent, a low boiling solvent or a solvent mixture of both, then emulsified in the presence of a surfactant and then added into a solution containing the hydrophilic colloid or further coated on the protective layer, etc.
The silver halide to be used in the present invention may be either one of silver chlorobromide, silver chloroiodobromide, silver iodobromide.
The grain size of the silver halide is not particularly limited, but one with a mean grain size of 0.5 μm or less may be preferable, and the so called mono-dispersed grains with 90% or more of the total grains falling within ±40% from the mean grain size as the center are preferred.
The silver halide grains may have a crystal habit which may be either cubic, tetradecahedral and octahedral, and may be also the tablet type grain as disclosed in Japanese Unexamined Patent Publication No. 108525/1983.
The silver halide grains in the silver halide emulsion layer of the present invention may be prepared according to any one of the single jet method such as the normal mixing method, the reverse mixing method, etc. or the double jet method according to the simultaneous mixing method, more preferably the simultaneous mixing method. Also, any of the ammonia method, the neutral method, the acidic method or the modified ammonia method as disclosed in Japanese Patent Publication No. 3232/1983, more preferably the acidic method or the neutral method, may be employed.
Also, within these silver halide grains, metal atoms such as iridium, rhodium, osmium, bismuth, cobalt, nickel, ruthenium, iron, copper, zinc, lead, cadmium, etc. may be contained.
When these metal atoms are to be contained, the content may be preferably within the range of 10 -8 to 10 -5 mol per mol of silver halide. The silver halide grains may be preferably of the surface latent image type.
The silver halide photographic emulsion in the silver halide emulsion layer according to the present invention (hereinafter called the silver halide photographic emulsion of the present invention) can be applied with chemical sensitization. The chemical sensitization method is inclusive of sulfur sensitization, reduction sensitization and noble metal sensitization, but in the present invention, it is preferable to perform chemical sensitization by sulfur sensitization alone. As the sulfur sensitizer, other than sulfur compounds contained in gelatin, various sulfur compounds such as thiosulfates, thioureas, thiazoles, rhodanines, etc. can be employed, and specifically the sulfur sensitizers as disclosed in U.S. Pat. Nos. 1,574,944, 2,410,689, 2,728,668 and Japanese Patent Publication No. 11892/1984 can be employed.
The silver halide photographic emulsion of the present invention can be imparted with photosensitivities to the respective desired photosensitive wavelength regions. Here, optical sensitization may be also effected by use of one or two or more kinds of spectral sensitizers. Examples of optically spectral sensitizers which can be used advantageously in the present invention may include cyanines, carbocyanines, melocyanines, trinucleus or tetranucleus melocyanines, trinucleus or tetranucleus cyanines, styryls, holopolar cyanines, hemine cyanines, oxonols, hemioxonols, etc., and these optically spectral sensitizers should preferably contain a basic group such as thiazoline, thiazole, etc. or a nucleus such as rhodanine, thiohydantoin, oxsazolidinedione, barbituric acid, thiobarbituric acid, pyrazolone, etc. as a part of the structure as the nitrogen containing heterocyclic nucleus, and such nucleus can be also substituted with alkyl, hydroxyalkylhalogen, phenyl, cyano, alkoxy, and also these optically spectral sensitizers may be condensed with carbon ring or heterocyclic ring.
In the silver halide photographic emulsion of the present invention, it is possible to add stabilizers such as tetrazaindenes, antifoggants such as triazoles, tetrazoles, covering power enhancers, antiirradiation agents such as oxanol dyes, dialkylaminobenzylidene dyes, etc., humectants such as polymer latices, and other additives used for photographic emulsions in general such as extenders, film hardeners to be used in combination outside of the present invention.
The support of the light-sensitive silver halide photographic material of the present invention may be one conventionally used such as polyester base, TAC base, baryta paper, laminated paper, glass plate, etc.
As the developer to be used for the light-sensitive silver halide photographic material of the present invention, there can be used either one of the developer used for light-sensitive silver halide photographic materials in general and the lith developer. The developing agent in these developers may include dihydroxybenzenes such as hydroquinone, chlorohydroquinone, catechol; 3-pyrazolidones such as 1-phenyl-3-pyrazolidone, 1-phenyl-4,4-dimethyl-3-pyrazolidone, 1-phenyl-4-methyl-3-pyrazolidone, 1-phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidone; and further p-aminophenols such as N-methyl-p-aminophenol, N-(4-hydroxyphenyl)glycine; p-phenylenediamines such as β-methanesulfonamide ester, ethylaminotoluidine, N,N-diethyl-p-phenylenediamine; and ascorbic acids, etc., and it is used as an aqueous solution containing at least one of such developing agents.
The developer can be constituted by adding otherwise preservatives such as sodium sulfite, potassium sulfite, formaldehyde, sodium hydrogen sulfite, hydroxylamine, ethylene urea; developing inhibitors of inorganic salts such as sodium bromide, potassium bromide, potassium iodide; at least one organic inhibitor such as 1-phenyl-5-mercaptotetrazole, 5-nitrobenzimidazole, 5-nitrobenzotriazole, 5-nitroindazole, 5-methylbenzotriazole, 4-thiazolin-2-thione, etc.; alkali agents such as sodium hydroxide, potassium hydroxide, etc.; alkanolamines having development accelerating effect such as diethanolamine, triethanolamine, 3-diethylamine-1-propanol, 2-methylamino-1-ethanol, 3-diethylamino-1,2-propanediol, diisopropylamine, 5-amino-1-pentanol, 6-amino-1-hexanol, etc.; buffering agents having buffering effect in developer such as sodium carbonate, sodium phosphate, aqueous carbonic acid solution, aqueous phosphoric acid solution, etc.; salts such as sodium sulfate, sodium acetate, sodium citrate, etc.; hard water softeners according to the chelation effect such as sodium ethylenediaminetetraacetate, sodium nitrilotriacetate, sodium hydroxydiaminetriacetate, etc.; development film hardners such as glutaralhehyde; solvents for developing agents and organic inhibitors such as diethylene glycol, dimethylformaldehyde, ethyl alcohol, benzyl alcohol; development controlling agents such as methylimidazoline, methylimidazole, polyethylene glycol, dodecylpyridinium bromide, etc.
The pH of the developer is not particularly limited, but may be preferably within the range of pH 9 to 13.
An example of the construction of the preferable developer for developing the light-sensitive silver halide photographic material of the present invention is as follows. That is, it is a developer prepared by adding 20 to 60 g/liter of hydroquinone and 0.1 to 2 g/liter of 1-phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidone or 0.1 to 2 g/liter of 1-phenyl-4,4-dimethyl-3-pyrazolidone as the developing agent, 10 to 200 g/liter of sodium sulfite or 10 to 200 g/liter of potassium sulfite as the developer preservative, 1 to 10 g of sodium bromide or potassium bromide as the developing inhibitor of inorganic salt, 1 to 50 g/liter of alkanolamines having development accelerating effect, 0.05 to 2 g/liter of 5-methylbenzotriazole or 0.01 to 2 g/liter of 5-nitroindazole as the organic inhibitor, 1 to 50 g/liter of sodium carbonate or 10 to 800 ml/liter of an aqueous phosphoric acid solution (1 mol/liter) as the buffering agent, 0.1 to 10 g/liter of disodium ethylenediaminetetraacetate as the chelating agent, and adjusting the pH to 11.0 to 12.5 with the use of an appropriate alkali agent (e.g. potassium hydroxide).
The light-sensitive silver halide photographic material of the present invention is developed with the developer as described above, and then the image is fixed via the process of fixing, water washing and drying. At this time, the developing temperature and the developing time in the developing process are not particularly limited, but the developing temperature may be preferably in the range of 20° to 45° C., and the developing time in the range of 15 seconds to 200 seconds.
The present invention is described in more detail by referring to Examples, but the present invention is not limited thereto.
EXAMPLE 1
Into an aqueous gelatin solution maintained at 40° C. were added simultaneously over 60 minutes an aqueous silver nitrate solution and an aqueous halide solution (KBr 40 mol %, NaCl 60 mol %) according to the controlled double jet method while maintaining pH at 3.0 and pAg at 7.7 to prepare a mono-dispersed silver chlorobromide emulsion with a mean grain size of 0.30 μm. The emulsion was desalted and washed with water in conventional manners, and then 15 mg of sodium thiosulfate was per mol of silver chlorobromide, followed by chemical ripening at 60° C. for 60 minutes.
Next, to the emulsion was added 1 g/Ag1 mol of 6-methyl-4-hydroxy-1,3-3a,7-tetrazaindene. As the sensitizing dye, 300 mg/Ag1 mol of the following compound (M) was added, and also 250 mg/Ag1 mol of a polyethylene glycol with a molecular weight of about 4000, the hydrazide compound of the present invention, and the compound represented by Formula [II] were added as shown in Table 1. Further, 1×10 -3 mol/Ag1 mol and 5×10 -3 mol of hydroquinone, a butyl acrylate latex polymer and an aqueous saponin solution as the extender were added to prepare an emulsion coating solution. Further, into the aqueous gelatin solution were added an aqueous sodium 1-decyl-2-(3-isopentyl)succinate-2-sulfonate solution, a methyl methacrylate copolymer with a mean particle size of 3.0 μm as the matte agent, and 2-hydroxy-4,6-dichloro-1,3,5-triazine sodium salt as the film hardener to prepare a coating solution for protective layer, which was coated by simultaneous overlaying together with the above emulsion coating solution on a PET base, followed by drying. At this time, the amount of gelatin attached was 2.5 g/m 2 in the emulsion layer, 1.0 g/m 2 in the protective layer, the amount of AgX grains attaches was 3.5 g/m 2 as calculated on silver, the amount of the butyl acrylate latex polymer attached was 2 g/m 2 , the amount of the matte agent attached was 30 mg/m 2 , the amount of the film hardener attached was 2 g/100 g gelatin based on the amount of gelatin attached of the the emulsion layer and the protective layer inclusive.
For the compound [II] of the present invention added in the silver halide emulsion layer, the compound of [II - 1], [II - 2], [II - 3], [II - 4] or [II - 5] shown below was employed. ##STR24##
TABLE 1______________________________________Hydrazide compound of theSam- present invention Compound of Formula [II]ple Compound Amount added Compound Amount addedNo. No. mol/Ag · 1 mol No. mol/Ag · 1 mol______________________________________ 1 -- -- -- -- 2 a 2 × 10.sup.-5 -- -- 3 b 2 × 10.sup.-5 -- -- 4 I-a-8 2 × 10.sup.-5 -- -- 5 I-b-5 2 × 10.sup.-5 -- -- 6 I-c-3 2 × 10.sup.-5 -- -- 7 I-c-11 2 × 10.sup.-5 -- -- 8 a 2 × 10.sup.-5 II-1 3 × 10.sup.-5 9 b 2 × 10.sup.-5 II-2 3 × 10.sup.-510 I-a-8 2 × 10.sup.-5 II-2 3 × 10.sup.-511 I-a-8 2 × 10.sup.-5 II-3 3 × 10.sup.-512 I-b-5 2 × 10.sup.-5 II-3 3 × 10.sup.-513 I-b-5 2 × 10.sup.-5 II-4 3 × 10.sup.-514 I-c-3 2 × 10.sup.-5 II-2 3 × 10.sup.-515 I-c-3 2 × 10.sup.-5 II-3 3 × 10.sup.-516 I-c-3 2 × 10.sup.-5 II-5 3 × 10.sup.-517 I-c-11 2 × 10.sup.-5 II-1 3 × 10.sup.-518 I-c-11 2 × 10.sup.-5 II-2 3 × 10.sup.-5______________________________________
The amount of Compound of Formula II added corresponds to 1.3×10 -2 to 2.1×10 -2 % by weight based on the hydrophilic colloid.
As the comparative compound added in the silver halide emulsion layer, the compounds (a)-(b) shown below were employed. ##STR25##
After the above samples of No. 1 to 18 were given stepwise exposure with a tungsten light source through a film wedge in conventional manner, they were developed with the developer shown below at 38° C. for 30 seconds, fixed, washed with water and dried, followed by evaluation of sensitivity, contrast and pepper fog. The contrast is represented by the slope (tan θ value) at the linear portion of the characteristic curve, and the degree of generation of pepper fog ranked at the four ranks of (5) no generation at all, (4) 1 to 2 in one field of vision, (3) small but low quality, (2) remarkably generated.
______________________________________(Developer recipe)Hydroquinone 34 gN-methyl-p-aminophenol 0.23 gDisodium ethylenediaminetetraacetate 1 g3-Diethylamino-1,2-propane diol 15 g5-Methylbenztriazole 0.4 gNa.sub.2 SO.sub.3 76 gNaBr 3 gNaCl 1.3 g1 mol/liter phosphoric acid solution 400 ml(after addition of NaOH necessary for adjusting to pH11.5, made up to one liter with water)(Fixer recipe)(Composition A)Ammonium thiosulfate (72.5% W/V aqueous solution) 240 mlSodium sulfite 17 gSodium acetate trihydrate 6.5 gBoric acid 6 gSodium citrate dihydrate 2 g(Composition B)Pure water (deionized water) 17 mlSulfuric acid (50% W/V aqueous solution) 4.7 gAluminum sulfate (aqueous solution 26.5 gcontaining 8.1% W/V as calculated on Al.sub.2 O.sub.3)______________________________________
During use of the fixer, the above composition A and the composition B were dissolved in this order in 500 ml of water, and made up to one liter before use. The pH of the fixer was adjusted to 6 with acetic acid.
The results are shown in Table 2.
TABLE 2______________________________________ PepperSample No. Sample content Sensitivity Contrast fog______________________________________ 1 Comparison 50 8 5 2 Comparison 98 12 2 3 Comparison 100 15 2 4 Comparison 120 17 2 5 Comparison 140 18 2 6 Comparison 130 18 2 7 Comparison 130 17 2 8 Comparison 95 10 2 9 Comparison 100 11 310 Present invention 120 16 511 Present invention 120 16 412 Present invention 140 17 513 Present invention 135 18 514 Present invention 120 18 515 Present invention 125 17 416 Present invention 130 17 417 Present invention 125 17 518 Present invention 125 16 5______________________________________
As is apparent from the results in Table 2, it can be appreciated that the samples obtained according to the present invention inhibit remarkably generation of pepper fog without impairing sensitivity and contrast. In Table 2, sensitivity is relative sensitivity.
EXAMPLE 2
Samples were obtained by coating and drying in entirely the same manner as in Example 1 except for using the compound [III] in place of the compound [II], and exposure-treated and evaluated in the same manner. The sample contents and results are shown in Table 3.
TABLE 3______________________________________Sample Compound Compound Relative PepperNo. [I] [III] sensitivity Contrast fog______________________________________19 -- -- 50 8 520 a III-1 98 10 221 b III-1 100 11 322 I-a-8 III-1 120 16 523 I-a-8 III-2 120 16 424 I-b-5 III-1 140 17 525 I-b-5 III-3 135 18 526 I-c-3 III-1 120 18 527 I-c-3 III-4 125 17 528 I-c-11 III-6 125 17 5______________________________________
Amount of compound was made 2×10 -5 mol/Ag1 mol for Formula [I], and 3×10 -5 mol/Ag1 mol for Formula [III]: which corresponds to 1.9×10 -2 to 2.4×10 -2 % by weight based on the hydrophilic colloid.
As is apparent from Table 3, it could be confirmed that the samples No. 22 to No. 28 by use of the compounds of the present invention had the effect of pepper fog inhibiting effect without impairing sensitivity and contrast as compared with comparative samples No. 19 to 21.
According to the present invention, a light-sensitive silver halide photographic material which is extremely high in contrast, and also improved in generation of peper fog without impairing tone hardening could be provided. | Disclosed is a light-sensitive silver halide photographic material having a hydrophilic colloid layer containing at least one layer of a light-sensitive silver halide emulsion layer provided on a support, wherein a hydrazide derivative is contained in the light-sensitive silver halide emulsion layer, and the above hydrophilic colloid layer contains at least one of the compounds represented by Formulae [II] and [III] shown below: ##STR1## wherein R1, R2 and R3 are as defined in the specification, ##STR2## wherein R1 and R2 are as defined in the specification. | 6 |
TECHNICAL FIELD
[0001] This invention relates generally to integrated circuits, and more specifically to an apparatus and method for a comparator circuit that uses AC positive feedback to reduce false switching due to slope reversals of a received signal.
BACKGROUND OF THE INVENTION
[0002] Input buffers are commonly used in a wide variety of integrated circuits. Buffers generally perform a number of advantageous functions when used in digital circuits. For example, buffers generally provide a high input impedance to avoid excessively loading circuits to which they are connected, and they have a low output impedance to simultaneously drive electrical circuits without excessive loading. Buffers can condition the signals applied to internal circuits so that the internal signals have well-defined logic levels and transition characteristics. Buffers are used, for example, to couple command, address and write data signals from command, address and data buses, respectively, of memory devices, including dynamic random access memory (“DRAM”) devices.
[0003] There are also several types of input buffers. For example, there are single ended input buffers in which a single input signal is applied to the buffer to cause the buffer to transition when the input signal transitions through predetermined voltage levels. Single-ended input buffers may also be used to compare the input signal to a reference voltage so that when the input signal transitions through the reference voltage the output of the buffer also transitions. Differential input buffer circuits are useful in digital circuits for determining whether an unknown input voltage is either above or below a fixed reference voltage. A conventional differential input buffer 100 is shown in FIG. 1 that includes a pair of differential amplifiers 101 , 103 , and an output coupled to an inverter 140 . The amplifiers 101 , 103 are connected in parallel between a PMOS transistor 102 that is coupled to a supply voltage V CC and an NMOS transistor 104 that is coupled to ground. When enabled by an active low signal EN_, the supply voltage V CC supplies a current through the PMOS transistor 102 to a node 105 . As a result, a constant current is provided to the amplifier 101 and a PMOS transistor 122 coupled to the amplifier 103 . Similarly, the supply voltage V CC is directly coupled to the gate of the transistor 104 such that a constant current is coupled from a node 115 through the transistor 104 , thereby drawing current through an NMOS transistor 110 coupled to the amplifier 101 and to the amplifier 103 . Therefore, the transistor 122 functions as a current source providing constant current to amplifier 103 , and transistor 110 functions as a current sink to discharge a constant current from amplifier 101 .
[0004] The two differential amplifiers 101 , 103 have essentially the same components, but are complementary configured with respect to each other. The differential amplifier 101 includes a pair of PMOS transistors 116 , 118 whose gates are coupled to each other and to node 105 , and further coupled to the drain of the PMOS transistor 118 . The transistors 116 , 118 are coupled to each other in a current mirror configuration so they both have the same gate-to-source voltage. As a result, the transistors 116 , 118 have the same source-to-drain resistance. The drains of the transistors 116 , 118 are coupled to the drains of two NMOS transistors 112 , 114 respectively, and receive an input signal V IN and a reference signal V REF at their respective gates. When the magnitude of the V IN signal is at ground potential, the transistor 112 is turned OFF. As a result, an output node 108 at which an OUT_signal is generated is driven high through the PMOS transistor 116 . An inverter 140 having an input coupled to the node 108 thus generates a low DIFF_OUT signal. When the magnitude of the V IN signal is at V CC , the transistor 112 is turned ON with a significantly higher gate-to-source voltage than the gate-to-source voltage of the PMOS transistor 116 . As a result, the resistance of the transistor 112 is significantly lower than the resistance of the transistor 116 . The voltage at the output node 108 is therefore low enough so that the inverter 140 outputs a high DIFF_OUT signal. As the magnitude of the V IN signal passes through the magnitude of the V REF signal, which is typically V CC /2, the NMOS transistors 112 , 114 have the same gate-to-source voltage and hence the same resistance. Furthermore, the NMOS transistors 112 , 114 will have the same gate-to-source voltage as the PMOS transistors 116 , 118 . If the NMOS transistors 112 , 114 have the same electrical characteristics as the PMOS transistors 116 , 118 , the PMOS transistors 116 , 118 will then have the same resistance as the NMOS transistors 112 , 114 . In such case, the OUT_voltage will be equal to V CC /2. Therefore, decreasing the magnitude of the V IN signal increases the resistance across the transistor 112 , reducing the current through the transistors 112 , 116 to cause the magnitude of the OUT_signal to increase. Conversely, increasing the magnitude of the V IN signal decreases the resistance across the transistor 112 , increasing the current through the transistors 112 , 116 to cause the magnitude of the OUT_signal to decrease.
[0005] The amplifier 103 includes components that are the same as the amplifier 101 , and thus for the sake of brevity, the components to the amplifier 103 will not be described in detail. The amplifier 103 has a topology that is complementary to the topology of the amplifier 101 so that the gates of NMOS transistors 128 , 130 are coupled together in a current mirror configuration so that both transistors 128 , 130 have the same resistance. As the magnitude of the V IN signal increases, the resistance of the PMOS transistor 126 increases to cause the magnitude of the OUT_signal to decrease. Conversely, as the magnitude of the V IN signal decreases, the resistance of the PMOS transistor 126 decreases to cause the magnitude of the OUT_signal to increase.
[0006] When the magnitude of the V IN signal decreases below V T , where V T is the threshold voltage of the NMOS transistor 112 , the transistor 112 is turned OFF and thus no longer responds to changes in the magnitude of V IN . Similarly, when the magnitude of the V IN signal increases above V CC -V T , where V T is the threshold voltage of the PMOS transistor 126 , the transistor 126 is turned OFF and thus no longer responds to changes in the magnitude of V IN . Thus, the buffer 100 can operate at all values of V IN from 0 to V CC , but only one amplifier 101 or 103 is operable with the magnitude of V IN below V T or above V CC -V T .
[0007] When the difference between V IN and V REF is small, such as when V IN transitions through V REF , the integrity of the input signal can be easily compromised by a number of interferences, such as improper bus termination, reflections, signal noise, and V REF noise. These factors can result in false switching of the buffer 100 as shown in FIG. 2 . For example, due to the presence of noise, the V REF signal may fluctuate about its predetermined value, such as V CC /2. As the V IN signal approaches the V REF signal, the noise interference on the V REF signal may overlap the V IN signal such that a slope reversal 205 occurs, where the buffer 100 detects V REF to be greater than V IN , when in fact VIN is intended to be greater than V REF , but may not be due to noise and or signal reflections. Consequently, the buffer 100 may falsely switch its output, thereby generating an incorrect response to the input signal and causing delays or resulting in errors to the overall operation of the system or component that relies on the buffer 100 .
[0008] Therefore, there is a need for a low current input buffer that reduces false switching in the presence of noise due to input signal slope reversals, and restores signal integrity.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a block diagram of a conventional differential input buffer.
[0010] FIG. 2 is a graphical representation of a false switching occurring to an input signal of the input buffer of FIG. 1 .
[0011] FIG. 3 is a block diagram of a differential input buffer having a capacitor coupled feedback to create AC positive feedback according to an embodiment of the invention.
[0012] FIG. 4 is a schematic diagram illustrating one embodiment of the differential input buffer circuit of FIG. 3 .
[0013] FIG. 5 is a functional block diagram illustrating a memory device that includes at least one differential input buffer circuit according to an embodiment of the invention.
[0014] FIG. 6 is a functional block diagram illustrating a computer system including the memory device of FIG. 5 .
DETAILED DESCRIPTION
[0015] Embodiments of the present invention are directed to an input buffer with AC positive feedback. Certain details are set forth below to provide a sufficient understanding of the invention. However, it will be clear to one skilled in the art that the invention may be practiced without these particular details. In other instances, well-known circuits, control signals, and timing protocols have not been shown in detail in order to avoid unnecessarily obscuring the invention.
[0016] FIG. 3 shows a block diagram of a buffer 300 according to an embodiment of the invention. The buffer 300 includes a differential comparator 302 that receives an input signal V IN and a reference signal V REF . Similarly to the conventional input buffer 100 , the comparator 302 of the buffer 300 compares the two input signals and generates an inverted output signal OUT_depending on whether the V IN signal is above or below the reference V REF . An inverter 304 drives and inverts the OUT_signal to generate a buffer output signal DIFF. However, as previously described, when the V IN signal approaches the trip point determined as V REF , false switching due to input signal slope reversals can occur. In such cases, the buffer 300 reduces false switching by coupling the DIFF signal at a node 308 to the comparator 302 , thereby providing positive feedback as the output signal transitions from one logic level to another. The feedback loop includes a capacitor 306 that creates AC positive feedback for a small period of time as it charges and discharges in response to the DIFF signal swings. The positive feedback provided by the output signal can overcome noise interferences of the V IN or V REF signals when the signal difference is small to maintain signal integrity at the switching point. If V IN is a periodic signal, such as a clock signal, the capacitance of the capacitor 306 is preferably chosen so that it charges from and discharges into the amplifier 302 over a duration that is less than one-half period of a periodic signal.
[0017] A differential input buffer 400 according to one embodiment of the invention is shown in FIG. 4 . Similar to the amplifiers 101 , 103 of the buffer 100 ( FIG. 1 ), the buffer 400 includes two differential amplifiers 401 , 403 whose components are essentially the same, but are complementary configured with respect to each other. The buffer 400 includes many of the same components as the buffer 100 operating in the same manner and, in the interest of brevity, these same components will not be described in detail.
[0018] The buffer 400 differs from the conventional buffer 100 shown in FIG. 1 in two respects. Most significantly, as explained in greater detail below, the buffer 400 receives AC positive feedback that makes it more immune to false switching resulting from noise. Second the buffer 400 includes three inverters 440 , 442 , 444 coupled to the node 108 to invert the OUT_signal and to provide a low impedance to the output at the node 108 . The use of three inverters 440 , 442 , 444 provides greater amplification of the OUT_signal so that the DIFF signal transitions high or low to V CC or to zero, respectively, well prior to the OUT_signal completely transitioning low-to-high or high-to-low.
[0019] The AC positive feedback mentioned above is provided by applying the DIFF signal at the output of the inverter 444 to the amplifiers 401 , 403 through respective third inputs of the amplifiers 401 , 403 at respective nodes 407 , 409 . The DIFF signal is applied to the nodes 407 , 409 through respective capacitors 406 , 408 to provide AC positive feedback to increase the drive of the OUT_signal at the node 108 as it transitions high or low. The AC positive feedback does not change the V REF trip point, and provides positive feedback for only a small period of time that the DIFF signal is transitioning from one logic level to another. The positive feedback provided as the V IN signal approaches the V REF reference results in a more stable, uniform transition characteristic since it counteracts any input signal slope reversals due to noise. For example, assume the OUT_signal is transitioning low and the DIFF signal is transitioning high in response to the V IN signal transitioning high. The capacitors 406 , 408 couple the low-to-high transition of the DIFF signal to the nodes 407 , 409 of the amplifiers 401 , 403 , causing the voltage at the nodes 407 , 409 to be driven high. The increased voltage at the node 407 of the amplifier 401 increases the resistance of the PMOS transistor 116 , thereby further decreasing the magnitude of the OUT_signal. The increased voltage at the node 409 of the amplifier 403 decreases the resistance of the NMOS transistor 130 , thereby also decreasing the magnitude of the OUT_signal. Thus, a rising V IN signal results in a falling OUT_signal and a rising DIFF signal. The rising DIFF signal further decreases the magnitude of the OUT_signal, thereby providing positive feedback during the time that the DIFF signal is rising. The amplifiers 401 , 403 respond to a falling V IN signal in the same manner to provide a falling DIFF signal to the nodes 407 , 409 that decrease the resistance of the PMOS transistor 116 in the amplifier 401 and increase the resistance of the NMOS transistor 130 in the amplifier 403 , thereby further increasing the OUT_signal.
[0020] The amount of positive feedback that is provided depends primarily on the size of the capacitor and gain of the amplifier at the nodes 407 , 409 , and are determined as part of the design parameters for the particular buffer 400 . In the ideal case, the AC positive feedback is provided for less than half the clock cycle of the V IN signal. For example, assuming the OUT_signal is pulled down and the DIFF signal is driven high in response to the OUT_signal. The capacitor 406 couples the low-to-high transition of the DIFF signal to the node 407 . The capacitor 406 is then discharged as current is drawn from the capacitor 406 by the node 407 . The time constant of the capacitor 406 and resistance at the node 407 should be set so that the capacitor 406 is substantially discharged by the time the DIFF signal transitions low.
[0021] The buffer 400 or another buffer according to an embodiment of the invention is shown in a synchronous dynamic random access memory (“SDRAM”) device 500 . The SDRAM device 500 includes an address register 512 that receives either a row address or a column address on an address bus 514 , preferably by coupling address signals corresponding to the addresses though one embodiment of input buffers 516 according to the present invention. The address bus 514 is generally coupled to a memory controller (not shown). Typically, a row address is initially received by the address register 512 and applied to a row address multiplexer 518 . The row address multiplexer 518 couples the row address to a number of components associated with either of two memory banks 520 , 522 depending upon the state of a bank address bit forming part of the row address. Associated with each of the memory banks 520 , 522 is a respective row address latch 526 , which stores the row address, and a row decoder 528 , which applies various signals to its respective array 520 or 522 as a function of the stored row address. The row address multiplexer 518 also couples row addresses to the row address latches 526 for the purpose of refreshing the memory cells in the arrays 520 , 522 . The row addresses are generated for refresh purposes by a refresh counter 530 , which is controlled by a refresh controller 532 .
[0022] After the row address has been applied to the address register 512 and stored in one of the row address latches 526 , a column address is applied to the address register 512 and coupled through the input buffers 516 . The address register 512 couples the column address to a column address latch 540 . Depending on the operating mode of the SDRAM 500 , the column address is either coupled through a burst counter 542 to a column address buffer 544 , or to the burst counter 542 which applies a sequence of column addresses to the column address buffer 544 starting at the column address output by the address register 512 . In either case, the column address buffer 544 applies a column address to a column decoder 548 which applies various signals to respective sense amplifiers and associated column circuitry 550 , 552 for the respective arrays 520 , 522 .
[0023] Data to be read from one of the arrays 520 , 522 is coupled to the column circuitry 550 , 552 for one of the arrays 520 , 522 , respectively. The data is then coupled through a read data path 554 to a data output register 556 . Data from the data output register 556 is coupled to a data bus 558 through data output buffers 559 . Data to be written to one of the arrays 520 , 522 is coupled from the data bus 558 to a data input register 560 through data input buffers 561 according to an embodiment of the invention. The data input register 560 then couples the write data to the column circuitry 550 , 552 where they are transferred to one of the arrays 520 , 522 , respectively. A mask register 564 may be used to selectively alter the flow of data into and out of the column circuitry 550 , 552 , such as by selectively masking data to be read from the arrays 520 , 522 .
[0024] The above-described operation of the SDRAM 500 is controlled by a command decoder 568 responsive to command signals received on a control bus 570 though command input buffers 572 according to an embodiment of the invention. These high level command signals, which are typically generated by a memory controller (not shown), are a clock enable signal CKE*, a clock signal CLK, a chip select signal CS*, a write enable signal WE*, a row address strobe signal RAS*, and a column address strobe signal CAS*, which the “*” designating the signal as active low. Various combinations of these signals are registered as respective commands, such as a read command or a write command. The command decoder 568 generates a sequence of control signals responsive to the command signals to carry out the function (e.g., a read or a write) designated by each of the command signals. These command signals, and the manner in which they accomplish their respective functions, are conventional. Therefore, in the interest of brevity, a further explanation of these control signals will be omitted.
[0025] Although, the memory device illustrated in FIG. 5 is a synchronous dynamic random access memory (“SDRAM”) 500 that includes the buffer 400 according to an embodiment of the invention, the buffer 400 can be used in other types of memory devices, as well as other types of digital devices.
[0026] FIG. 6 shows a computer system 600 containing the SDRAM 500 of FIG. 5 . The computer system 600 includes a processor 602 for performing various computing functions, such as executing specific software to perform specific calculations or tasks. The processor 602 includes a processor bus 604 that normally includes an address bus, a control bus, and a data bus. In addition, the computer system 600 includes one or more input devices 614 , such as a keyboard or a mouse, coupled to the processor 602 to allow an operator to interface with the computer system 600 . Typically, the computer system 600 also includes one or more output devices 616 coupled to the processor 602 , such output devices typically being a printer or a video terminal. One or more data storage devices 618 are also typically coupled to the processor 602 to allow the processor 602 to store data in or retrieve data from internal or external storage media (not shown). Examples of typical storage devices 618 include hard and floppy disks, tape cassettes, and compact disk read-only memories (CD-ROMs). The processor 602 is also typically coupled to cache memory 626 , which is usually static random access memory (“SRAM”), and to the SDRAM 100 through a memory controller 630 . The memory controller 630 is coupled to the SDRAM 500 through the normally control bus 570 and the address bus 514 . The data bus 558 is coupled from the SDRAM 500 to the processor bus 604 either directly (as shown), through the memory controller 630 , or by some other means.
[0027] From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. For example, many of the components described above may be implemented using either digital or analog circuitry, or a combination of both. Accordingly, the invention is not limited except as by the appended claims. | An input buffer having a comparator that receives an input signal, a reference signal and a positive feedback. The comparator compares the input signal relative to the reference signal and generates an output signal transitioning between a first logic state and a second logic state responsive to the magnitude of the input signal transitioning through the magnitude of the reference signal. The comparator intensifies the output signal in response to the positive feedback from the output of the comparator while the output signal transitions from the first logic state to the second logic state. | 7 |
BACKGROUND OF THE INVENTION
[0001] This invention relates generally to fluid catalytic cracking units, and more particularly to fluid catalytic cracking units having risers with improved hydrodynamics through the use of baffles.
[0002] In a fluid catalytic cracking (FCC) unit such as illustrated in FIG. 1 , hydrocarbons are contacted in a reaction zone with a catalyst composed of finely divided particulate material. Inert diluent, such as steam, enters the riser and is mixed with catalyst. The hydrocarbon feed and an inert diluent, such as steam, are introduced to the riser 10 by a hydrocarbon feed distributor 5 which atomizes the hydrocarbon feed as it enters the riser 10 . The hydrocarbon feed and inert diluent fluidize the catalyst and transport it in the riser 10 . The catalyst promotes the cracking reaction. As the cracking reaction proceeds, a substantial amount of highly carbonaceous material, referred to as coke, is deposited on the catalyst. The coke-containing catalyst is separated from the hydrocarbon product in a separation zone 20 and removed from the reactor through conduit 30 , while the hydrocarbon product exits through the top of the reactor. The coke is burned from the catalyst by contact with an oxygen-containing stream that serves as a fluidization medium in a high temperature regeneration zone 25 . Coke-containing catalyst is replaced by essentially coke-free catalyst from the regeneration zone 25 through conduit 35 . In some FCC units, there is a conduit 40 in which a portion of the catalyst is recycled without going through the regeneration zone 25 .
[0003] FCC risers have traditionally suffered from vapor-catalyst slip caused by the inherent non-uniformities of upward moving particle-containing flows. These non-uniformities manifest themselves primarily as core-annular structures: the core of the flow is dilute and moves upward at a higher velocity, while there is a high concentration of catalyst near the wall which forms a dense, slow-moving annulus. The annulus can actually move downward in some cases. This annular flow results in decreased conversion in the riser because the faster moving dilute core under-converts the feed and the slower moving and/or downward moving annulus over-cracks the primary FCC products, leading to increased dry gas production.
SUMMARY OF THE INVENTION
[0004] One aspect of the invention is a riser reactor. In one embodiment, the riser reactor includes a vertical riser having a hydrocarbon feed inlet; and a row of baffles located more than 6 m above the hydrocarbon feed inlet, a front face of the baffle facing the center of the riser, a lower end of the baffle attached to a wall of the riser and the baffle inclined inward from the wall at an angle of about 90° or less.
[0005] In another embodiment, the riser reactor includes a vertical riser having a hydrocarbon feed inlet; and a row of baffles located more than 6 m above the hydrocarbon feed inlet, a front face of the baffle facing the center of the riser, a lower end of the baffle attached to a wall of the riser, and the baffle inclined inward from the wall at an angle of about 90° or less.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is an illustration of one embodiment of an FCC unit.
[0007] FIG. 2A is a cross-section of one embodiment of a riser pipe with internal baffles.
[0008] FIG. 2B is an illustration of one embodiment of a riser pipe with internal baffles.
[0009] FIG. 3 is a sectional view along A-A of FIG. 2A of one embodiment of a baffle.
[0010] FIG. 4 is a sectional view along A-A of FIG. 2A of another embodiment of a baffle.
[0011] FIG. 5 is a sectional view along A-A of FIG. 2A of another embodiment of a baffle.
[0012] FIGS. 6A-C are illustrations of one embodiment of two subsets of a row of baffles.
DETAILED DESCRIPTION OF THE INVENTION
[0013] The use of baffles in the mixing zone of the riser alters the flow profile so that it approaches true plug flow, alleviating the problems associated with the core-annulus structure. The baffles break up the outer annulus and redistribute the catalyst into the center of the riser flow. This results in higher conversion in the riser and less overcracking of the products.
[0014] The attachment of baffles to the riser wall in the mixing zone above the hydrocarbon feed inlet has been shown to make the catalyst holdup distribution in the riser more uniform using Computational Flow Dynamics (CFD) computer simulation. The baffles also improve the flow profile in the riser by slowing down the upward core flow, which results in less short-circuiting. In addition, the baffles minimize the downward flow of the annulus.
[0015] FIG. 2A shows one embodiment of a riser 100 having a row of baffles 115 extending inward from the wall 110 . The front face 140 of the baffles is facing the center of the riser. As shown, the baffles 115 are equally spaced around the circumference of the riser 100 and cover substantially the whole circumference of the riser.
[0016] In one embodiment, the baffles are positioned symmetrically around the circumference of the riser. In another embodiment, the baffles are arranged non-symmetrically.
[0017] In some embodiments, the baffles can cover less of the circumference, if desired. For example, typically at least about 30% of the circumference is covered with baffles, or at least about 40%, or at least about 50%, or at least about 60%, or at least about 70%, or at least about 80%, or at least about 90%, or at least about 95%.
[0018] The baffles extend inward from the wall a distance d up to about 25% of the radius R of the riser, typically in the range of about 15% to about 25%. The baffles desirably extend over about ⅛ of the cross-sectional area of the riser 110 .
[0019] The baffles are typically in the range of about 0.15 to about 0.30 m in length. The length depends in part on the radius of the riser and the angle from the wall.
[0020] The angle of the baffle (about 90° from vertical or less) coupled with the ceramic lining ensure the erosion resistance of the attachment.
[0021] The riser desirably has at least two rows of baffles along its length so that the core-annulus structure does not return to its original state as it flows up the riser. However, if there are too many rows of baffles, the catalyst-laden vapors flowing upward will simply bypass the baffles altogether, effectively reducing the diameter of the riser.
[0022] FIG. 2B illustrates a riser pipe 10 with three rows of internal baffles 115 A, 115 B, and 115 C. The riser pipe 10 has a lift zone 50 and a reaction zone 55 . The regenerated catalyst enters the lift zone 50 through conduit 35 , and the recycled catalyst (if present) enters through conduit 40 . The hydrocarbon feed enters through the feed distributer 5 which separates the lift zone 50 from the reaction zone 55 . Three rows of baffles 115 A, 115 B, and 115 C are located in the riser pipe 10 . As an example, the lift zone 50 could be about 10 m, and the reaction zone about 20 m. The first row of baffles 115 A could be about 6 m above the feed distributor 5 , with a second row of baffles 115 B about 5 m above the first, and a third row 115 C about 5 m above the second row.
[0023] There are typically up to three rows of baffles for a riser that is about 30 m high. The first row of baffles is located more than about 6 m above the highest feed inlet in the riser (steam, hydrocarbon, catalyst, etc.), typically in the range of about 6 m to about 6.5 m above the feed inlet(s). Additional rows can be positioned at evenly spaced intervals, e.g., about 5 m apart. The separation between the rows will vary depending on the length of the riser, the number of rows of baffles, and whether any of the rows are divided into subsets as discussed below. Generally, the rows will be in the range of about 5 m to about 10 m apart. In one embodiment, the baffles are arranged in the same position around the circumference for all of the rows. In another embodiment, the baffles in one row are offset from the baffles in the previous row.
[0024] In one embodiment, each row has the same number of baffles. In another embodiment, there can be a different number of baffles in at least two rows.
[0025] The bottom of the baffle is attached to the wall of the riser, for example, by welding. The baffles are inclined inward from vertical at an angle b of up to about 90°. In one embodiment, the baffles are inclined from the vertical at an angle of about 90°. In another embodiment, the baffles are inclined in a range of about 10° to about 45°.
[0026] FIG. 3 shows a one embodiment of a baffle 115 . The baffle 115 has a support plate 120 . The support plate 120 has a ceramic liner 125 on the upper end and the front face 140 (the side facing the upward flow). The baffle is typically welded to the riser 110 forming an angle b of about 90°. The baffle 115 can be supported by a support 130 , if desired. The support 130 can be metal plate welded to the wall 110 and the support plate 120 , for example.
[0027] FIG. 4 shows another embodiment of the baffle 115 . In this embodiment, the baffle 115 forms an angle b of between about 10° to about 45° from the side of the riser 110 . The support plate 120 is covered on the front face 140 and the upper end by ceramic 125 .
[0028] A number of factors can be considered in determining the appropriate angle for the baffles in a particular riser. One consideration is mixing, with larger angles producing greater mixing. Another factor is the amount of erosion, which is greater for larger angles. Still another factor is the pressure drop generated by the baffles, which is greater for baffles having larger angles than for those with smaller angles. In addition, the effect of thermal differential growth should be evaluated. When the angle b is about 90°, the wall and the baffle might expand at different rates, which could potentially lead to cracking. With smaller angles, such as about 10° to about 45°, the relatively long inclined support plate provides a longer path for heat transfer. This minimizes the thermal differential growth of the baffle, especially under transient conditions, such as start-up or shut-down.
[0029] FIG. 5 shows another embodiment of the baffle 115 . A ceramic sleeve 135 covers the front and back faces 140 , 145 of the support plate 120 . The ceramic sleeve 135 is attached to the support plate. Erosion resistance is improved because both sides of the support plate 120 are covered with ceramic.
[0030] In some embodiments, a row of baffles (or more than one) can be divided into one or more subsets, with each subset being positioned at a different vertical level in the riser, as illustrated in FIGS. 6A-C . As shown in FIG. 6A , subset A is positioned at level A, while subset B is positioned at level B. The baffles 115 A in subset A can be angularly offset from the baffles 115 B in subset B, as shown in FIGS. 6B-C . As shown, the baffles in subset A are at 90° intervals around the riser. The baffles in subset B are also at 90° intervals, but they are offset 45° from the baffles of subset A. This may help to promote mixing in some embodiments.
[0031] Although FIG. 6 shows two subsets with four baffles in each subset and a 45° offset from one level to the next, those of skill in the art will understand that more than two subsets can be used, there can be the same or different numbers of baffles in each subset, and other offset angles can be used as desired.
[0032] In one embodiment, the baffles in the subsets can form a stair step arrangement on the riser wall.
[0033] In one embodiment, the baffles in the subsets are arranged symmetrically around the riser wall, and in other embodiments, the baffles are arranged non-symmetrically.
[0034] The baffles in a subset will generally be within about 1 to 2 m of each other.
[0035] The baffles are made of a material having sufficient erosion- and temperature-resistance to withstand the riser conditions. Suitable materials include metal plates, such as stainless steel plates, covered with ceramic on at least the front face facing the upward flow to prevent erosion. The back side away from the flow can be covered with abrasion-resistant refractory. Alternatively, both sides can be covered with ceramic.
[0036] The baffles can be made of fusion-cast ceramic tiles with embedded metal, such as Corguard® made by St. Gobain. If an extended metal piece is used during manufacture, the baffles can be welded to the riser wall as shown in FIG. 3 , for example. The welding area can then be re-coated with standard FCC riser refractory.
[0037] Another method of making the baffles involves welding metal pieces, (e.g., trapezoid-shaped metal pieces) to the riser wall as shown in FIG. 1 . Prefabricated ceramic sleeves can then be attached to the welded metal pieces. The ceramic sleeves can be further secured by creating a lip, for example, by bending or welding, on the metal element. Alternatively, they can be additionally secured using a low-expansion cementing compound between the sleeve and the metal element. This method is not limited to the use of Corguard® tiles.
[0038] The attachment of the baffles to the riser can take place in situ, if desired. The refractory material inside the riser can be removed manually in the area where the baffles are being installed. The metal pieces would then be welded to the riser wall. The ceramic liner would be attached to the metal piece. The affected areas could then be re-coated with refractory.
[0039] It is to be understood that the features of any of the embodiments discussed above may be recombined with any other of the embodiments or features disclosed herein. While particular features and embodiments of a process and reactor system has been shown and described, other variations of the invention will be obvious to those of ordinary skill in the art. All embodiments considered to be part of this invention are defined by the claims that follow. | Fluid catalytic cracking units having risers with improved hydrodynamics through the use of baffles are described. The baffles break up the high concentration of catalyst in the slower moving outer annulus and redistribute it into the faster moving, more dilute center of the riser flow. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a press roll for paper machines, and more particularly to a press roll for use in the press section of a paper machine for removing water from wet paper and making the paper smooth-surfaced.
Roll presses and extended nip presses (ENP) are known as typical means for pressing wet paper for use in the press section of paper machines.
The roll press is so adapted that wet paper supported on a felt is passed between two rotary rolls under pressure for the removal of water. With the ENP, wet paper supported on a felt is dewatered by being passed between a rotary roll and a belt to which pressure is applied by a pressure shoe having a large nip width.
The rotary roll used in either of these systems has a hard surface in view of the pressing effect and surface smoothness. For example, the roll press comprises the combination of a rotary roll having a hard surface and serving as a top press roll and a rubber-covered roll or the like serving as a bottom press roll.
It is required that such hard-surfaced rotary rolls be usable over a prolonged period of time, withstanding a high load and high-speed rotation. To meet this requirement, stone rolls of natural granite (granite rolls) are widely used. Generally, the stone roll can be mirror-finished over the surface, has high surface hardness, is resistant to abrasion by the doctor blade which is usually provided for removing bits of extraneous stock, permits smooth release of wet paper and is less prone to the deposition of pitch or the like contained in the pulp even when used for a long period. Because of these characteristics, the stone roll has the advantage of being less likely to cause breaks of paper during pressing.
While stone rolls are prepared from natural stone, the stone material is expensive and requires a long period for delivery since the material is difficult to obtain owing to the recent trend toward depletion of resources. In fact, extreme difficulties are encountered in collecting, transporting and processing large stones for making stone rolls which become longer and must be larger than in the past.
Further because the material is a polycrystalline natural stone, there is a substantial problem in that the rolls produced differ in the surface characteristics (such as porosity, surface hardness and water retentivity), even a single roll often differing in such surface characteristics from portion to portion.
SUMMARY OF THE INVENTION
The main object of the present invention is to provide a press roll which is free of the foregoing problems for use in paper machines.
The paper machine press roll of the present invention is characterized in that the roll comprises a metal core, a ground layer formed over the outer periphery of the core and made of a metal material having a smaller coefficient of expansion than the metal material forming the core, and a mixture layer formed over the outer periphery of the ground layer and comprising a ceramic and a water retentivity imparting particulate material such as mica.
The water retentivity imparting particulate substance is at least one powder selected from the group consisting of mica powder, glass balloons, glass beads, glass powder, stone powder, sand and fluorine-containing resin powder.
The metal core for use in the present invention is made, for example, of iron, stainless steel, copper, brass or the like.
The metal core is formed with a ground layer made of a metal material which has a smaller coefficient of expansion than the surface material of the metal core but a greater coefficient of expansion than ceramics.
The ground layer serves to bond a ceramic layer to the metal core and to prevent the core from corrosion. The ground layer of metal material is smaller than iron-type metals and copper-type metals in coefficient of expansion. To be suitable, the ground layer is usually about 9×10 -6 to 14×10 -6 /° C. in coefficient of expansion. From the viewpoint of corrosion resistance, examples of suitable materials for the ground layer are molybdenum-type metals and nickel-type metals, among which nickel-chromium alloys and nickel-chromium-aluminum alloys are especially preferable.
The ground layer is formed, for example, by gas spray coating or gas plasma spray coating using the desired metal in the form of particles.
The ground layer has a thickness of about 100 to about 500 micrometers, and serves as a kind of buffer in the event of thermal expansion, preventing the separation between the core and the ceramic layer effectively due to thermal expansion.
When required, a corrosion inhibiting coating may be formed between the ground layer and the core to protect the core from corrosion.
Examples of materials for forming the corrosion inhibiting coating are nickel, nickel-aluminum alloys, copper, stainless steel, etc. Preferably, the coating is 100 to 500 micrometers in thickness.
The mixture layer comprising the ceramic and the water retentivity imparting particulate substance such as mica, contains 5 to 30 wt. % of the particulate substance as mixed with the ceramic.
If the amount of mica or like water retentivity imparting substance is less than 5 wt. %, the contemplated effect will not be available, whereas amounts exceeding 30 wt. % impair the surface roughness and give a lower strength to the mixture layer. The press roll obtained is therefore undesirable.
According to the invention, the mixture layer is formed from a powder of metal oxide for forming the ceramic and mica or like water retentivity imparting particulate substance, by covering the ground layer around the metal core with these materials by plasma spray coating (e.g. water-stabilized plasma spray coating or gas plasma spray coating). Thus, the mixture layer can be formed easily.
In this case, the ceramic and the particulate substance such as mica are mixed together and sprayed onto the ground layer at the same time, or the ceramic and the particulate substance are individually applied to the ground layer using separate powder feeders. In the latter case, it is desirable to feed the particulate substance to a low-temperature portion of the plasma used for spray coating, whereby the degradation of the particulate substance can be prevented.
Examples of typical metal oxides for forming the ceramic are gray alumina (94% Al 2 O 3 --2.5% TiO 2 ), white alumina (99% Al 2 O 3 ), titania (TiO 2 ), alumina-titania (Al 2 O 3 --TiO 2 , mullite (Al 2 O 3 --SiO 2 ), zirconia-mullite (Al 2 O 3 --ZrO 2 --SiO 2 ) and the like. These materials can be used singly or in admixture. Other metal oxide, low-melting alloy, metal carbide, metal nitride or the like which is applicable by spray coating can be admixed with such a material to form the ceramic.
The particle size of the material to be used for spray coating is 10 to 200 micrometers to be suitable.
Useful plasma spray coating apparatus are water-stabilized plasma spray coating apparatus wherein water is used as the plasma source, gas plasma spray coating apparatus wherein argon, helium, hydrogen or nitrogen is used as the plasma source, etc.
For spray coating, the core to be coated is rotated, whereby a layer can be formed which comprises a uniform mixture of ceramic and mica or like water retentivity imparting particulate substance. The thickness of the mixture layer to be formed is usually 1 to 30 mm although variable with the dimensions of the roll, pressure to be applied, etc.
Another feature of the present invention is that at least in a surface layer portion of the mixture layer thus formed, at least one organic high polymer selected from the group consisting of synthetic resins and waxes is filled in the interstices between particles of the ceramic and particles of the water retentivity imparting particulate substance such as mica.
The organic high polymer is a substance selected from the group consisting of epoxy resin, phenol resin, polyurethane resin, silicone resin, fluorine-containing resin and waxes.
The synthetic resin, wax or like organic high polymer is applied, as it is or in the form of a solution, to the surface of the mixture layer by means such as coater, brush or spray, whereby the high polymer is caused to penetrate into or fill the interstices between the ceramic partices and particles of particulate substance.
The sythetic resin is thereafter hardened by a curing reaction, or the solvent of the synthetic resin or wax solution is evaporated off, whereby the interstices are fully filled with the resin or wax.
Since the organic high polymer penetrates into or fills the interstices or impregnates the surface layer portion of the mixture layer, the material or solution to be used preferably has a low viscosity.
For example when epoxy resin is used as the organic high polymer, the resin per se is, for example, 50 to 500 cps in viscosity.
When the epoxy resin to be used as it is is less than 50 cps in viscosity, it is difficult to obtain the resin, whereas when exceeding 500 cps, the resin encounters difficulty in penetrating into the interstices between the ceramic particles and particles of water retentivity imparting substance such as mica.
Further when other organic high polymer, i.e., phenol resin, polyurethane resin, silicone resin, fluorine-containing resin or wax is to be used, such material or the solution thereof obtained by diluting the material with a suitable solvent needs to have the lowest possible viscosity.
The organic high polymer, such as synthetic resin or wax, fills up the interstices between the ceramic particles and particles of water retentive substance at least in the surface layer portion of the mixture layer. Preferably, the resin or wax fills the surface layer portion having 1/4 to 1/2 of the overall thickness of the mixture layer from the surface thereof since the paper machine press roll is reground during use.
The roll having the mixture layer of the ceramic and the particulate substance thus coated with the organic high polymer is ground over the surface to a surface roughness of 0.2 to 2.0 micrometers (Ra) (according to JIS B0601, except where mica or like water retentivity imparting substance is present), the ground surface being filled with the high polymer in the interstices, whereby a press roll is obtained for use in paper machines.
According to another feature of the present invention, the paper machine press roll has a ceramic layer which is free from mica or like water retentivity imparting particulate substance.
More specifically, the invention provides a paper machine press roll characterized in that the roll comprises a metal core, a ground layer formed over the outer periphery of the core and made of a metal material having a smaller coefficient of expansion than the metal material forming the core, and a ceramic layer formed over the outer periphery of the ground layer, at least a surface layer portion of the ceramic layer being filled in the interstices between ceramic particles with at least one organic high polymer selected from the group consisting of synthetic resins and waxes.
The metal core and the ground layer have the same construction as already described, and the ceramic layer has the above feature and is formed from a metal oxide powder by covering the ground layer around the metal core with the powder material by plasma spray coating.
A synthetic resin, wax or like organic high polymer is applied, as it is or in the form of a solution, to the surface of the ceramic layer by means such as coater, brush or spray, whereby the high polymer is caused to penetrate into or fill the interstices between ceramic particles.
The synthetic resin is thereafter hardened by a curing reaction, or the solvent of the synthetic resin or wax solution is evaporated off, whereby the interstices are fully filled up with the resin or wax.
Since the organic high polymer penetrates into or fills the interstices or impregnates the surface layer portion of the ceramic layer, the material or solution to be used preferably has a low viscosity as already described above.
Preferably, the resin or wax fills the surface layer portion having 1/4 to 1/2 of the overall thickness of the ceramic layer from the surface thereof since the paper machine roll is reground during use.
The roll having the ceramic layer coated with the organic high polymer is ground over the surface to a surface roughness of 0.2 to 2.0 micrometers (Ra) (according to JIS B0601). The ground surface is filled with the high polymer in the interstices. Thus, a press roll is obtained for use in paper machines.
The roll of the invention comprises a metal core, a ground layer formed around the metal core and made of a metal material of small coefficient of expansion, and a mixture layer formed around the ground layer and comprising a ceramic and mica or like water retentivity imparting particular substance. The water retentivity given by the particulate substance such as mica renders wet paper smoothly releasable from the roll, obviating the trouble to be caused by the wet paper.
When an organic high polymer such as synthetic resin or wax is filled in the interstices between ceramic particles and particles of mica or like particulate substance at least in a surface layer portion of the mixture layer, the roll is given improved surface smoothness to release wet paper therefrom more effectively.
When the kind and particle size of mica or like water retentivity imparting substance are altered, the roll is selectively usable for pressing a particular kind of paper.
Further the paper machine press roll of the present invention may be formed with a ceramic layer free from mica or like particulate substance for imparting water retentivity. More specifically, the ceramic layer is formed over the outer periphery of the ground layer around the metal core and has a surface layer portion which is filled with at least one organic high polymer selected from among synthetic resins and waxes, in the interstices between ceramic particles.
The paper machine press roll of the invention having either construction is usable in place of conventional stone rolls, has improved surface smoothness, releases wet paper effecitvely with good stability without permitting adhesion thereto since the ceramic layer surface has no voids, is less likely to permit adhesion of pitch even when used for a prolonged period of time, can be mirror-finished to give surface smoothness to wet paper pressed, has such surface hardness as to be resistant to abrasion by the doctor blade for removing bits of extraneous stock, has a strength to withstand a heavy load or high-speed rotation for a long period of time, is uniform in surface characteristics and can be easily produced with the specified surface characteristics.
The present invention will be described in greater detail with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view schematically showing a paper machine press roll of the invention;
FIG. 2 is an enlarged view in section showing the portion A in FIG. 1;
FIG. 3 is an enlarged view in section of the portion B in FIG. 2 to show an organic high polymer as filled in interstices between ceramic particles in a ceramic layer;
FIG. 4 is an enlarged view in section of the portion B in FIG. 2 to show a mixture layer of a ceramic and mica or like water retentivity imparting particulate substance; and
FIG. 5 is an enlarged view in section of the portion B in FIG. 2 to show an organic high polymer as filled in interstices between ceramic particles and particles of mica or like water retentivity imparting particulate substance.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Example 1
With reference to FIG. 1, a cast iron cylinder (14.0×10 -6 /° C. in coefficient of expansion) measuring 6000 mm in length, 5000 mm in surface length and 490 mm in diameter was used as the metal core 2 of a paper machine press roll 1. The surface of the core 2 was cleaned and degreased with an organic solvent (trichlene) and then sandblasted to remove rust and extraneous matter and form a rough surface. While rotating the core 2, a nickel-chromium alloy powder (10 to 44 micrometers in particle size) was applied to the outer periphery by a gas spray coating apparatus (using oxygen-acetylene gas) to form a ground layer 4 having a thickness of 100 micrometers (see FIG. 2).
Next, while rotating the core 2 having the ground layer 4, a gray alumina powder, 50 micrometers in mean particle size, was applied to the layer 4 over a period of 6 hours by a water plasma spray coating apparatus to form a ceramic layer 3 of gray alumina powder having a thickness of 5.3 mm.
The water plasma spray coating was conducted under the following conditions.
Input power: 400 V, 400 A (350 KVA)
Spray gun: 380 V, 420 A
Rate of feed of gray alumina: 40 kg/hr (about 230 kg)
Distance between gun and core: 300-400 mm
Traverse speed: 10-20 mm/sec
Effective amount of deposition of gray alumina: about 50%
Next, the surface of the ceramic-coated roll thus prepared was preheated, and a preheated epoxy resin having a viscosity of 100 to 200 cps (comprising 100 parts by weight of PELNOX 106 as the main component, 80 parts by weight of PELCURE HV19 as a curing agent and 4 parts by weight of an accelerator, product of NIPPON PELNOX Co., Ltd.) was applied by a coater to the surface of the ceramic layer 3 so as to fill the interstices between ceramic particles. The coating was cured to form a resin layer 6 (see FIG. 3).
The surface of the roll coated with the epoxy resin was ground with a diamond abrasive stone for finishing. The paper machine press roll 1 thus obtained was 500.2 mm in outside diameter and 0.5 micrometer (Ra) in surface roughness as determined according to JIS B0601.
The press roll 1 thus prepared was used for pressing wood-free paper at a line pressure of 90 kg/cm and a speed of 800 m/min. The roll was usable for wet paper free of any trouble.
The wood-free paper had the following composition.
______________________________________Broad-leaved tree kraft pulp (LBKP) 80 parts by weightConiferous tree kraft pulp (NBKP) 20 parts by weightAluminum sulfate 1 part by weightTalc 5 parts by weightSize agent 0.5 part by weightFreeness 400 c.c.______________________________________
Comparative Example 1
The same roll as prepared in the above example except that the ceramic layer 3 was prepared only from gray alumina and was not coated with epoxy resin was used under the same conditions as in Example 1 for pressing the same wood-free paper. The roll became unusable owing to adhesion of paper.
The comparative roll was 3.0 to 5.0 micrometers (Ra) in surface roughness (according to JIS B0601).
Example 2
With reference to FIG. 1, a cast iron cylinder (14.0×10 -6 /° C. in coefficient of expansion) measuring 6300 mm in length, 3850 mm in surface length and 1120 mm in diameter was used as the metal core 2 of a paper machine press roll 1. The surface of the core 2 was cleaned and degreased with an organic solvent (trichlene) and then sandblasted to remove rust and extraneous matter and form a rough surface. While rotating the core 2, a nickel-chromium alloy powder (10 to 44 micrometers in particle size) was applied to the outer periphery by a gas spray coating apparatus (using oxygen-acetylene gas) to form a ground layer 4 having a thickness of 100 micrometers (see FIG. 2).
Next, while rotating the core 2 having the ground layer 4, a mixture of gray alumina powder and mica powder (4:1 in weight ratio), 50 micrometers in means particle size, was applied to the layer 4 over a period of 50 hours by a water plasma spray coating apparatus to form a mixture layer 3 of gray alumina powder 5 and mica powder 7 having a thickness of 5.3 mm (see FIG. 4).
The water plasma spray coating was conducted under the following conditions.
Input power: 400 V, 400 A (350 KVA)
Spray gun: 380 V, 420 A
Rate of feed of alumina-mica mixture: 38 kg/hr
Distance between gun and core: 300-400 mm
Traverse speed: 10-20 mm/sec
Effective amount of deposition of alumina-mica mixture: about 50%
Subsequently, the surface of the roll was ground with a diamond abrasive stone for finishing. The paper machine press roll 1 thus formed, which is shown in FIGS. 1, 2 and 4, was 1130 mm in outside diameter and 1.5 micrometers in surface roughness (Ra) as determined according to JIS B0601 (except at the mica portions).
The press roll 1 thus prepared was used for pressing wood-free paper at a line pressure of 90 kg/cm and a speed of 800 m/min. The roll was usable for wet paper free of any trouble.
The wood-free paper had the following composition.
______________________________________Broad-leaved tree kraft pulp (LBKP) 80 parts by weightConiferous tree kraft pulp (NBKP) 20 parts by weightAluminum sulfate 1 part by weightTalc 5 parts by weightSize agent 0.5 part by weightFreeness 400 c.c.______________________________________
Example 3
The surface of a roll having the same mixture layer 3 and prepared in the same manner as in Example 2 was preheated after the formation of the layer 3. A preheated epoxy resin having a viscosity of 100 to 200 cps (comprising 100 parts by weight of PELNOX 106 as the main component, 80 parts by weight of PELCURE HV 19 as a curing agent and 4 parts by weight of an accelerator, product of NIPPON PELNOX Co., Ltd.) was applied by a coater to the surface of the mixture layer 3 of ceramic and mica so as to fill the interstices between ceramic particles and mica particles. The coating was cured to form a resin layer 6 (see FIG. 5).
Subsequently, the surface of the roll coated with the epoxy resin was ground with a diamond abrasive stone for finishing. The paper machine press roll 1 thus formed, which is shown in FIGS. 1, 2 and 5, was 0.5 micrometer in surface roughness (Ra) as determined according to JIS B0601 (except at the mica portions).
The press roll 1 thus obtained was used for pressing the same wood-free paper as above under the same conditions as in Example 1. The roll was usable for wet paper free of any trouble.
Comparative Example 2
The same roll as obtained in the above example except that the mixture layer 3 of ceramic and mica was not coated with epoxy resin was prepared. This comparative roll was 3.0 to 5.0 micrometers in surface roughness (Ra) (according to JIS B0601). When the roll was used under the same conditions as in Example 2 for pressing the same wood-free paper as above, the roll became unusable owing to adhesion of paper. | A paper machine press roll comprising a metal core, a ground layer formed over the outer periphery of the core and made of a metal material having a small coefficient of expansion, and a mixture layer formed over the outer periphery of the ground layer and comprising a ceramic and a water retentivity imparting particulate substance such as mica. At least in a surface layer portion of the mixture layer, an organic high polymer such as synthetic resin or wax is filled in the interstices between particles of the ceramic and particles of the water retentivity imparting substance. | 3 |
[0001] This application is a continuation of U.S. patent application Ser. No. 11/636,065, filed Dec. 8, 2006, which claims priority to U.S. Provisional Application Ser. No. 60/748,855, filed Dec. 9, 2005, all of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention pertains to crystalline lestaurtinib hydrates and crystalline lestaurtinib hemihydrate hemicetonitrileate and crystalline lestaurtinib hemihydrate hemitetrahydrofuranate, processes to reproducibly make them and methods of treating patients using them.
BACKGROUND OF THE INVENTION
[0003] Lestaurtinib is an semi-synthetic, orally bioavailable receptor-tyrosine kinase inhibitor that has been shown to have therapeutic utility in treating diseases such as acute myeloid leukemia, chronic myeloid leukemia and acute lymphocytic leukemia. It is a synthetic derivative of K-252a, a fermentation product of Nonomurea longicatena , and belongs to a class of indolocarbazole alkaloids. U.S. Pat. No. 4,923,986 describes lestaurtinib, also known as (9S-(9α,10β, 12α))-2,3,9,10,11,12-hexahydro-10-hydroxy-10-(hydroxymethyl)-9-methyl-9,12-epoxy-1H-diindolo[1,2,3-fg:3′,2′,1′-kl]pyrrolo[3,4-i][1,6]benzodiazocin-1-one (CAS Registry No. 111358-88-4) and utility thereof.
[0004] Lestaurtinib solvates can have different melting points, solubilities or rates of solubility, which physical properties, either alone or in combination, can effect their bioavailability. Because knowledge of crystallinity, or lack thereof, of lestaurtinib solvates can provide guidance during clinical development, there is an existing need for identification of different crystalline forms of solvates of lestaurtinib, processes to reproducibly make them and methods of treating patients using them.
SUMMARY OF THE INVENTION
[0005] One embodiment of this invention, therefore, pertains to isolated crystalline lestaurtinib hydrates characterized, when measured at about 25° C. with Cu-Kα radiation, by a powder diffraction pattern with at least three peaks having respective 2θ values of about 7.1°, 8.2°, 10.2°, 12.9°, 14.5°, 14.9°, 16.4°, 20.6°, 25.3°, 26.1° or 26.4°.
[0006] Another embodiment pertains to crystalline lestaurtinib monohydrate characterized, when measured at about 25° C. with Cu-Kα radiation, by a powder diffraction pattern with at least three peaks having respective 2θ values of about 7.1°, 8.2°, 10.2°, 12.9°, 14.5°, 14.9°, 16.4°, 20.6°, 25.3°, 26.1° or 26.4°.
[0007] Still another embodiment pertains to crystalline lestaurtinib monohydrate characterized in the orthorhombic crystal system and P2 1 2 1 2 1 space group, when measured at about 25° C. with Mo-Kα radiation, by lattice parameters a, b and c of 7.101 Å, 11.994 Å and 25.000 Å, respectively.
[0008] Still another embodiment pertains to crystalline lestaurtinib hydrates characterized, when measured at about 25° C. with Cu-Kα radiation, by a powder diffraction pattern with at least three peaks having respective 2θ values of about 7.0°, 14.0°, 14.4°, 14.8°, 15.6°, 18.9°, 25.5°, 26.5° or 35.5°.
[0009] Still another embodiment pertains to crystalline lestaurtinib trihydrate characterized, when measured at about 25° C. with Cu-Kα radiation, by a powder diffraction pattern with at least three peaks having respective 2θ values of about 7.0°, 14.0°, 14.4°, 14.8°, 15.6°, 18.9°, 25.5°, 26.5° or 35.5°.
[0010] Still another embodiment pertains to crystalline lestaurtinib trihydrate characterized in the orthorhombic crystal system and P2 1 2 1 2 1 space group, when measured at about −100° C. with Mo-Kα radiation, by lattice parameters a, b and c of 7.0489 ű0.0006 Å, 12.720±0.001 Å and 25.292 ű0.002 Å, respectively.
[0011] Still another embodiment pertains to compositions comprising or made from an isolated crystalline lestaurtinib hydrate, or a mixture thereof, and an excipient.
[0012] Still another embodiment pertains to a method of treating patients having a disease caused or exacerbated by unregulated or overexpressed receptor-tyrosine kinase comprising administering thereto a therapeutically acceptable amount of an isolated crystalline lestaurtinib hydrate, or a mixture thereof.
[0013] Still another embodiment pertains to a method of treating patients having acute myeloid leukemia comprising administering thereto a therapeutically acceptable amount of an isolated crystalline lestaurtinib hydrate, or a mixture thereof.
[0014] Still another embodiment pertains to a method of treating patients having chronic myeloid leukemia comprising administering thereto a therapeutically acceptable amount of an isolated crystalline lestaurtinib hydrate, or a mixture thereof.
[0015] Still another embodiment pertains to a method of treating patients having acute lymphocytic leukemia comprising administering thereto a therapeutically acceptable amount of an isolated crystalline lestaurtinib hydrate, or a mixture thereof.
[0016] Still another embodiment pertains to a method of treating patients having chronic lymphocytic leukemia comprising administering thereto a therapeutically acceptable amount of an isolated crystalline lestaurtinib hydrate, or a mixture thereof.
[0017] Still another embodiment pertains to a process for making crystalline lestaurtinib monohydrate comprising
[0018] exposing crystalline lestaurtinib anhydrate or crystalline lestaurtinib trihydrate to relative humidity between about 10% and 40% and
[0019] isolating the crystalline lestaurtinib monohydrate.
[0020] Still another embodiment pertains to a process for making crystalline lestaurtinib trihydrate comprising
[0021] exposing crystalline lestaurtinib anhydrate or crystalline lestaurtinib monohydrate to relative humidity greater than 40% and
[0022] isolating the crystalline lestaurtinib trihydrate.
[0023] Still another embodiment pertains to crystalline lestaurtinib hemihydrate hemiacetonitrileate characterized, when measured at about 25° C. with Cu-Kα radiation, by a powder diffraction pattern with at least three peaks having respective 2θ values of about 7.7°, 8.0°, 8.2°, 9.8°, 12.0°, 14.1°, 14.6°, 15.5°, 17.2°, 17.9°, 18.2°, 18.6°, 19.8°, 21.6°, 22.3°, 23.3°, 25.4° or 25.6.
[0024] Still another embodiment pertains to crystalline lestaurtinib hemihydrate hemiacetonitrileate characterized in the monoclinic crystal system and P2 1 space group, when measured at about −100° C. with Mo-Kα radiation, by lattice parameters a, b and c of 13.6358 ű0.0001 Å, 22.8320 ű0.0004 Å and 15.8260 ű0.0002 Å, respectively, and β of 113.147°±0.001°.
[0025] Still another embodiment pertains to crystalline lestaurtinib hemihydrate hemitetrahydrofuranate characterized in the monoclinic crystal system and P2 1 space group, when measured at about −100° C. with Mo-Kα radiation, by lattice parameters a, b and c of 13.541 ű0.004 Å, 22.756 ű0.008 Å and 15.935 ű0.005 Å, respectively, and β of 113.411°±0.006°.
[0026] Still another embodiment pertains to a process for making crystalline lestaurtinib hemihydrate hemiacetonitrileate comprising
[0027] providing a mixture of lestaurtinib and acetonitrile, in which the lestaurtinib is completely soluble in the acetonitrile;
[0028] causing crystalline lestaurtinib hemihydrate hemiacetonitrileate to exist in the mixture and
isolating the crystalline lestaurtinib hemihydrate hemiacetonitrileate.
[0030] Still another embodiment pertains to a process for making crystalline lestaurtinib hemihydrate hemiacetonitrileate comprising
[0031] providing a mixture comprising lestaurtinib and acetonitrile, in which the lestaurtinib is completely soluble in the acetonitrile;
[0032] causing crystalline lestaurtinib hemihydrate hemiacetonitrileate to exist in the mixture by adding water to the mixture; and
[0033] isolating the crystalline lestaurtinib hemihydrate hemiacetonitrileate.
[0034] Still another embodiment pertains to a process for making crystalline lestaurtinib hemihydrate hemitetrahydrofuranate comprising
[0035] providing a mixture of lestaurtinib and tetrahydrofuran, in which the lestaurtinib is completely soluble in the tetrahydrofuran;
[0036] causing crystalline lestaurtinib hemihydrate hemitetrahydrofuranate to exist in the mixture and
[0037] isolating the crystalline lestaurtinib hemihydrate hemitetrahydrofuranate.
[0038] Still another embodiment pertains to a process for making crystalline lestaurtinib hemihydrate hemitetrahydrofuranate comprising
[0039] providing a mixture comprising lestaurtinib and tetrahydrofuran, in which the lestaurtinib is completely soluble in the tetrahydrofuran;
[0040] causing crystalline lestaurtinib hemihydrate hemitetrahydrofuranate to exist in the mixture by adding water to the mixture; and
[0041] isolating the crystalline lestaurtinib hemihydrate hemitetrahydrofuranate.
DETAILED DESCRIPTION OF THE INVENTION
[0042] Different crystalline forms of a given drug have physical, pharmaceutical, physiological and biological properties which can sharply differ from one other. This invention pertains to crystalline forms of lestaurtinib solvates. It is meant to be understood that the term “isolated lestaurtinib solvate,” as used herein, means a particular crystalline lestaurtinib solvate such as, but not limited to, lestaurtinib monohydrate, lestaurtinib trihydrate, lestaurtinib hemihydrate hemiacetonitrileate, lestaurtinib hemihydrate hemitetrahydrofuranate, mixtures thereof and the like. It is also meant to be understood that the term “isolated lestaurtinib hydrate,” as used herein, means a particular crystalline lestaurtinib hydrate such as, but not limited to, lestaurtinib monohydrate, lestaurtinib trihydrate and the like.
[0043] Crystalline lestaurtinib monohydrate is stable at about 10% to about 40% relative RH at about 25° C. At ambient temperature and above 40% RH, the monohydrate readily converts to the trihydrate. When ground with a mortar and pestle, crystalline lestaurtinib monohydrate's ability to absorb water is reduced by a factor of about 6. Thus it takes about 6 times longer to absorb similar amounts of water when ground than unground.
[0044] Lestaurtinib monohydrate can be made by exposing the trihydrate to RH levels of 40% or less at ambient temperature or by heating the trihydrate between 80° C. and 200° C., followed by exposure to ambient conditions for about 10 minutes. After the exposure period, the sample must be stored in a sealed container.
[0045] Crystalline lestaurtinib anhydrate is stable at ambient temperature between about 0% and about 5% RH but absorbs moisture above 5% RH to form crystalline lestaurtinib monohydrate. Existence of crystalline lestaurtinib anhydrate was demonstrated by dynamic moisture sorption gravimetry (DMSG) which displayed, at 25° C., a solid-state phase between 0% and 5% RH with less than 0.5% water. Because moisture-mediated crystallization was not observed during RH levels between 5% and 10%, it was concluded that the solid at 5% RH was crystalline; and because the solid contained less than 0.5% water, it was also determined that it was an anhydrate.
[0046] Crystalline lestaurtinib anhydrate can be produced by either exposing crystalline lestaurtinib anhydrate to RH levels 5% or less at ambient temperature or by heating the trihydrate between 80° C. and 200° C. and storing the product under moisture-free conditions. The sample can absorb water from the atmosphere during the transfer period.
[0047] Crystalline lestaurtinib hemihydrate hemiacetonitrileate is a crystalline mixed solvate with about ½ mole equivalent of water and about ½ mole equivalent of acetonitrile. The solvents are entrapped within the crystal lattice and can be removed by heating a sample between 130° C. and 220° C.
[0048] Powder X-Ray diffraction (PXRD) pdata were obtained with a Scintag model X1 unit with a copper target (1.54060 Å wavelength radiation: 45 Kv and 40 ma); scan rate: 1° per minute continuous; and a scan range of 2-40° 2θ at ambient temperature using a Peltier cooled detector tuned for copper radiation. All XRPD samples were gently ground to a fine powder in a mortar and pestle prior to analysis.
[0049] The term “amorphous,” as used herein, means a supercooled liquid or a viscous liquid which looks like a solid but does not have a regularly repeating arrangement of molecules that is maintained over a long range and does not have a melting point but rather softens or flows above its glass transition temperature.
[0050] The term “anti-solvent,” as used herein, means a solvent in which a compound is substantially insoluble.
[0051] The term “crystalline,” as used herein, means having a regularly repeating arrangement of molecules or external face planes.
[0052] The term “isolating” as used herein, means separating a compound from a solvent, anti-solvent, or a mixture of solvent and anti-solvent to provide a solid, semisolid or syrup. This is typically accomplished by means such as centrifugation, filtration with or without vacuum, filtration under positive pressure, distillation, evaporation or a combination thereof. Isolating may or may not be accompanied by purifying during which the chemical, chiral or chemical and chiral purity of the isolate is increased. Purifying is typically conducted by means such as crystallization, distillation, extraction, filtration through acidic, basic or neutral alumina, filtration through acidic, basic or neutral charcoal, column chromatography on a column packed with a chiral stationary phase, filtration through a porous paper, plastic or glass barrier, column chromatography on silica gel, ion exchange chromatography, recrystallization, normal-phase high performance liquid chromatography, reverse-phase high performance liquid chromatography, trituration and the like.
[0053] The term “miscible,” as used herein, means capable of combining without separation of phases.
[0054] The term “solvate,” as used herein, means having on a surface, in a lattice or on a surface and in a lattice, a solvent such as water, acetic acid, acetone, acetonitrile, benzene, chloroform, carbon tetrachloride, dichloromethane, dimethylsulfoxide, 1,4-dioxane, ethanol, ethyl acetate, butanol, tert-butanol, N,N-dimethylacetamide, N,N-dimethylformamide, formamide, formic acid, heptane, hexane, isopropanol, methanol, methyl ethyl ketone, 1-methyl-2-pyrrolidinone, mesitylene, nitromethane, polyethylene glycol, propanol, 2-propanone, pyridine, tetrahydrofuran, toluene, xylene, mixtures thereof and the like. A specific example of a solvate is a hydrate, wherein the solvent on the surface, in the lattice or on the surface and in the lattice, is water. Hydrates may or may not have solvents other than water on the surface, in the lattice or on the surface and in the lattice of a substance.
[0055] The term “solvent,” as used herein, means a substance, typically a liquid, that is capable of completely or partially dissolving another substance, typically a solid. Solvents for the practice of this invention include water, acetic acid, acetone, acetonitrile, benzene, chloroform, carbon tetrachloride, dichloromethane, dimethylsulfoxide, 1,4-dioxane, ethanol, ethyl acetate, butanol, tert-butanol, N,N-dimethylacetamide, N,N-dimethylformamide, formamide, formic acid, heptane, hexane, isopropanol, methanol, methyl ethyl ketone, 1-methyl-2-pyrrolidinone, mesitylene, nitromethane, polyethylene glycol, propanol, 2-propanone, pyridine, tetrahydrofuran, toluene, xylene, mixtures thereof and the like.
[0056] The term “supersaturated,” as used herein, means having a compound in a solvent in which it is completely dissolved at a certain temperature but at which the solubility of the compound in the solvent at that certain temperature is exceeded.
[0057] Unless stated otherwise, percentages stated throughout this specification are weight/weight (w/w) percentages.
[0058] Mixtures comprising lestaurtinib and solvent may or may not have chemical and diastereomeric impurities, which, if present, may be completely soluble, partially soluble or essentially insoluble in the solvent. The level of chemical or diastereomeric impurity in the mixture may be lowered before or during isolation of Lestaurtinib Crystalline Form 1 by means such as distillation, extraction, filtration through acidic, basic or neutral alumina, filtration through acidic, basic or neutral charcoal, column chromatography on a column packed with a chiral stationary phase, filtration through a porous paper, plastic or glass barrier, column chromatography on silica gel, ion exchange chromatography, recrystallization, normal-phase high performance liquid chromatography, reverse-phase high performance liquid chromatography, trituration and the like.
[0059] Mixtures of lestaurtinib and solvent, wherein the lestaurtinib is completely dissolved in the solvent may be prepared from a crystalline lestaurtinib, amorphous lestaurtinib, a lestaurtinib solvate or a mixture thereof.
[0060] It is meant to be understood that, because many solvents and anti-solvents contain impurities, the level of impurities in solvents and anti-solvents for the practice of this invention, if present, are at a low enough concentration that they do not interfere with the intended use of the solvent in which they are present. Solvents used were HPLC, reagent or USP grade and were used as received.
[0061] The invention provides methods of treating diseases and conditions in a patient comprising administering thereto a therapeutically effective amount of lestaurtinib. Accordingly, lestaurtinib is useful for treating a variety of therapeutic indications. For example, lestaurtinib is useful for the treatment of cancers such as carcinomas of the pancreas, prostate, breast, thyroid, colon and lung; malignant melanomas; glioblastomas; neuroectodermal-derived tumors including Wilm's tumor, neuroblastomas and medulloblastomas; and leukemias such as acute myeloid leukemia (AML), chronic myeloid leukemia (CML), acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL); pathological conditions of the prostate such as prostatic hypertrophy or prostate cancer; carcinomas of the pancreas, such as pancreatic ductal adenocarcinoma (PDAC); hyperproliferative disorders such as proliferative skin disorders including actinic keratosis, basal cell carcinoma, squamous cell carcinoma, fibrous histiocytoma, dermatofibrosarcoma protuberans, hemangioma, nevus flammeus, xanthoma, Kaposi's sarcoma, mastocytosis, mycosis fungoides, lentigo, nevocellular nevus, lentigo maligna, malignant melanoma, metastatic carcinoma and various forms of psoriasis, including psoriasis vulgaris and psoriasis eosinophilia; and myeloproliferative disorders and related disorders associated with activation JAK2 and myeloproliferative disorders and related disorders including, but are not limited, to myeloproliferative diseases such as, for example, polycythemia vera (PV), essential thrombocythemia (ET), myelofibrosis with myeloid metaplasia (MMM), also called chronic idiopathic myelofibrosis (CIMF), unclassified myeloproliferative disorders (uMPDs), hypereosinophilic syndrome (HES), and systemic mastocytosis (SM).
[0062] Lestaurtinib hydrates can be administered by any means that results in contact of the active agent with the agent's site of action in the body of the patient. Lestaurtinib hydrates can be administered by any conventional means available, either as individual therapeutic agents or in combination with other therapeutic agents. Lestaurtinib hydrates are preferably administered to a patient in need thereof in therapeutically effective amounts for the treatment of the diseases and disorders described herein.
[0063] Therapeutically effective amounts of a lestaurtinib hydrate can be readily determined by an attending diagnostician by use of conventional techniques. The effective dose can vary depending upon a number of factors, including type and extent of progression of the disease or disorder, overall health of a particular patient, biological efficacy of the lestaurtinib, formulation of the lestaurtinib hydrate, and route of administration of the forms of the lestaurtinib hydrate. Lestaurtinib hydrates can also be administered at lower dosage levels with gradual increases until the desired effect is achieved.
[0064] As used herein, the term “about,” as used herein, refers to a range of values from ±10% of a specified value. For example, the phrase “about 50 mg” includes ±10% of 50 or from 45 to 55 mg.
[0065] Typical dose ranges of lestaurtinib hydrates comprise from about 0.01 mg/kg to about 100 mg/kg of body weight per day or from about 0.01 mg/kg to 10 mg/kg of body weight per day. Daily doses for adult humans includes about 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 90, 100, 120, 140, 160 and 200 mg and an equivalent dose for a human child. Lestaurtinib hydrates can be administered in one or more unit dose forms and can also be administered one to four times daily, including twice daily (BID). Unit dose ranges of lestaurtinib comprise from about 1 to about 400 mg administered one to four times a day, or from about 10 mg to about 200 mg BID, or 20-80 mg BID, or 60-100 mg BID or from about 40, 60, 80, or 100 mg BID.
[0066] Dosage of forms of lestaurtinib hydrates can also be in the form of liquids or suspensions in a concentration of between 15 to 25 mg/mL, 16 mg/mL or 25 mg/mL. The liquid or suspension dosage forms of lestaurtinib hydrates can include the equivalent of the doses (mg) described above. For example, dosages of lestaurtinib hydrates can include 1 to 5 mL of the 25 mg/mL solution, or 1, 1.2, 1.4, 1.6, 1.8, 2, 2.2, 2.4, 2.6, 2.8, 3, 3.2, 3.4, 3.6, 3.8, or 4 mL of the 25 mg/mL solution, wherein a 60 mg dose of a lestaurtinib hydrate can be provided in 2.4 mL of solution, an 80 mg dose of a lestaurtinib hydrate can be provided in 3.2 mL of solution and a 100 mg dose of a lestaurtinib hydrate can be provided in 4 mL of solution. Additionally, a 20 mg dose of a lestaurtinib hydrate can be provided with a 1.25 mL of a 16 mg/mL solution.
[0067] The daily dose of a lestaurtinib hydrate can range from 1 mg to 5 mg/kg (normalization based on a mean body weight close to 65 kg). For example, a daily dose of a form of a lestaurtinib hydrate is from about 1 to 3 mg/kg or from about 1.2 to 2.5 mg/kg, or about 1.2, 1.4, 1.6, 1.8, 2, 2.2, 2.4, 2.6, 2.8 or 3 mg/kg. In an alternate method of describing an effective dose, an oral unit dose of a lestaurtinib hydrate is one that is necessary to achieve a blood serum level of about 0.05 to 20 μg/mL or from about 1 to 20 μg/mL in a patient.
[0068] Lestaurtinib hydrates can be formulated into pharmaceutical compositions by mixing the forms with one or more pharmaceutically acceptable excipients. It is meant to be understood that pharmaceutical compositions include any form of a lestaurtinib hydrate or any combination thereof.
[0069] The term “pharmaceutically acceptable excipients,” as used herein, includes any and all solvents, dispersion media, coatings, antibacterial and antifungal agents, isotonic and absorption delaying agents and the like. The use of such media and agents for pharmaceutical active substances is well known in the art, such as in Remington: The Science and Practice of Pharmacy, 20 th ed.; Gennaro, A. R., Ed.; Lippincott Williams & Wilkins: Philadelphia, Pa., 2000. Except insofar as any conventional media or agent is incompatible with the active ingredient, its use in the therapeutic compositions is contemplated. Supplementary active ingredients can also be incorporated into the compositions.
[0070] Excipients for preparation of compositions comprising lestaurtinib hydrates to be administered orally include, for example, agar, alginic acid, aluminum hydroxide, benzyl alcohol, benzyl benzoate, 1,3-butylene glycol, carbomers, castor oil, cellulose, cellulose acetate, cocoa butter, corn starch, corn oil, cottonseed oil, cross-povidone, diglycerides, ethanol, ethyl cellulose, ethyl laureate, ethyl oleate, fatty acid esters, gelatin, germ oil, glucose, glycerol, groundnut oil, hydroxypropylmethyl celluose, isopropanol, isotonic saline, lactose, magnesium hydroxide, magnesium stearate, malt, mannitol, monoglycerides, olive oil, peanut oil, potassium phosphate salts, potato starch, povidone, propylene glycol, Ringer's solution, safflower oil, sesame oil, sodium carboxymethyl cellulose, sodium phosphate salts, sodium lauryl sulfate, sodium sorbitol, soybean oil, stearic acids, stearyl fumarate, sucrose, surfactants, talc, tragacanth, tetrahydrofurfuryl alcohol, triglycerides, water and mixtures thereof. Excipients for preparation of compositions comprising forms of lestaurtinib hydrates to be administered ophthalmically or orally include, for example, 1,3-butylene glycol, castor oil, corn oil, cottonseed oil, ethanol, fatty acid esters of sorbitan, germ oil, groundnut oil, glycerol, isopropanol, olive oil, polyethylene glycols, propylene glycol, sesame oil, water and mixtures thereof. Excipients for preparation of compositions comprising lestaurtinib hydrates to be administered osmotically include, for example, chlorofluoro-hydrocarbons, ethanol, water and mixtures thereof. Excipients for preparation of compositions comprising forms of lestaurtinib hydrates to be administered parenterally include, for example, 1,3-butanediol, castor oil, corn oil, cottonseed oil, dextrose, germ oil, groundnut oil, liposomes, oleic acid, olive oil, peanut oil, Ringer's solution, safflower oil, sesame oil, soybean oil, U.S.P. or isotonic sodium chloride solution, water and mixtures thereof. Excipients for preparation of compositions comprising forms of lestaurtinib hydrates to be administered rectally or vaginally include, for example, cocoa butter, polyethylene glycol, wax and mixtures thereof.
[0071] Dosage forms of lestaurtinib hydrates and compositions comprising lestaurtinib hydrates depend upon the route of administration. Any route of administration is contemplated, including oral, mucosal (e.g. ocular, intranasal, pulmonary, gastric, intestinal, rectal, vaginal and uretheral) or parenteral (e.g. subcutaneous, intradermal, intramuscular, intravenous, or intraperitoneal.
[0072] Pharmaceutical compositions are most preferably administered orally, preferably in forms such as tablets, capsules, powders, pills, liquids/suspensions or gels/suspensions or emulsions, lyophilizates and all other different forms described in patents and applications mentioned herein, more preferably as tablets, capsules and liquids/suspensions or gels/suspensions. The administration vehicle can comprise one or more pharmaceutically acceptable carriers that are likely to ensure the solid state or crystalline form's stability (e.g. suspension in oil).
[0073] Lestaurtinib hydrates can be formulated as a variety of pharmaceutical compositions and dosage forms, such as those described in U.S. Pat. Nos. 6,200,968 and 6,660,729 and PCT Publication No. 04/037928, each of which is incorporated herein by reference. In particular, the lestaurtinib can be formulated as microemulsions or dispersions.
[0074] In certain embodiments, compositions comprise a lestaurtinib hydrate, propylene glycol and a polyoxyethylene sorbitan fatty acid ester, examples of which include TWEEN® 20 (polyoxyethylene 20 sorbitan monolaurate), TWEEN® 40 (polyoxyethylene 20 sorbitan monopalmitate), and TWEEN® 80 (polyoxyethylene 20 sorbitan monooleate). In a particular embodiment, the lestaurtinib hydrate is present in a concentration of 25 mg/mL. In other embodiments, the ratio of the propylene glycol to the polyoxyethylene sorbitan fatty acid ester ranges from 50:50 to 80:20 or 50:50 or 80:20.
[0075] In other embodiments, compositions comprise a lestaurtinib hydrate, a polyoxyl stearate and polyethylene glycol (“PEG”), examples of which include PEG of 300-8000, 400-3350 or 400-1500 Daltons or PEG-400, PEG-600, PEG-1000, PEG-1450, PEG-1500, PEG-400/PEG-1000, PEG-400/PEG-1450, PEG-600/PEG-1000 or PEG-600/PEG-1450.
[0076] In other still other embodiments, the polyoxyl stearate is polyoxyl 40 stearate (MYRJ 52®). In particular embodiments, the lestaurtinib hydrate is present in a concentration of 25 mg/mL. In other embodiments, the ratio of polyethylene glycol to the polyoxyl stearate ranges from 50:50 to 80:20 or ratios of 50:50 or 80:20. In certain embodiments, compositions comprise PEG-400, PEG-1000 and polyoxyl stearate in a ratio of 25:25:50 or PEG-400, PEG-1450 and polyoxyl stearate in a ratio of 25:25:50 or PEG-600, PEG-1000 and polyoxyl stearate in a ratio of 25:25:50 or PEG-600:PEG-1450:polyoxyl stearate in a ratio of 25:25:50. In other embodiments, the composition comprises PEG-400, PEG-1000 and polyoxyl stearate in a ratio of 40:40:20 or PEG-400, PEG-1450 and polyoxyl stearate in a ratio of 40:40:20 or PEG-600, PEG-1000 and polyoxyl stearate in a ratio of 40:40:20 or PEG-600, PEG-1450 and polyoxyl stearate in a ratio of 40:40:20.
[0077] In another embodiment of this invention, an the composition includes an antioxidant is in. The term “antioxidant,” as used herein, means a substance that retards deterioration by oxidation or inhibits reactions promoted by oxygen or peroxides. Antioxidants include, but are not limited to, ascorbic acid, fatty acid esters of ascorbic acid, butylated hydroxytoluene (BHT), propyl gallate, butylated hydroxyanisole, mixtures thereof and the like. In certain embodiments of this invention, microemulsions or solid solution compositions comprising lestaurtinib further comprise BHT, and in particular 0.02% w/w BHT.
[0078] Lestaurtinib hydrates can be made by synthetic chemical processes, examples of which is shown hereinbelow. It is meant to be understood that the order of the steps in the processes may be varied, that reagents, solvents and reaction conditions may be substituted for those specifically mentioned, and that moieties succeptable to undesired reaction may be protected and deprotected, as necessary.
[0079] The following examples are presented to provide what is believed to be the most useful and readily understood description of procedures and conceptual aspects of this invention.
Preparative Example 1
[0080] Lestaurtinib and the methanolate thereof were prepared as described in U.S. Pat. No. 4,923,986.
Example 1
Lestaurtinib Crystalline Form 1
[0081] A mixture of lestaurtinib methanolate in methanol and acetone was polish filtered. The filtrant was constant-volume distilled with addition of isopropyl acetate. When the boiling point of the solvent stabilized at 82° C., the mixture was cooled and filtered.
Example 2
Crystalline Hydrated Lestaurtinib
[0082] A mixture of lestaurtinib (400 mg) in refluxing acetone (200 mL), in which the lestaurtinib was completely soluble, was treated with water until turbid, cooled, stored under darkness at ambient temperature for 3 days and filtered through a medium porosity sintered-glass funnel. The filtrant was washed with water and air-dried. Exposure of the product to relative humidity less than 40% provided crystalline lestaurtinib monohydrate. Exposure of the product to relative humidity of 40% or greater provided crystalline lestaurtinib trihydrate.
Example 2A
Crystalline Hydrated Lestaurtinib
[0083] A mixture of lestaurtinib (1.2 g) in refluxing 1,3-dioxolane, in which the lestaurtinib was completely soluble (120 mL), was poured into water (600 mL), stored under darkness at ambient temperature for 6 days and filtered through a medium porosity sintered-glass funnel. The filtrant was washed with water (10 mL) and air-dried. Exposure of the product to relative humidity less than 40% provided crystalline lestaurtinib monohydrate. Exposure of the product to relative humidity of 40% or greater provided crystalline lestaurtinib trihydrate.
Example 3
Crystalline Lestaurtinib Hemihydrate Hemiacetonitrileate
[0084] A solution of lestaurtinib (300 mg) in refluxing acetonitrile (150 mL), in which the lestaurtinib was completely soluble, was treated with water until turbid, cooled, stored under darkness at ambient temperature for 24 hours and filtered.
Example 4
Amorphous Lestaurtinib
[0085] A mixture of lestaurtinib (1.6 g) in isopropanol (350 mL) and 1,3-dioxolane (50 mL) at 80° C., and in which the lestaurtinib was completely soluble, was concentrated under vacuum. The concentrate was washed with isopropanol (10 mL) and air dried.
Example 4A
Amorphous Lestaurtinib
[0086] A mixture of lestaurtinib (1.1 g) in acetone (250 mL), in which the lestaurtinib was completely soluble, was concentrated at 65° C. under vacuum. The concentrate was washed with isopropanol (10 mL) and air dried.
[0087] Additional ways to prepare amorphous lestaurtinib are shown in TABLE 1. Concentrations were conducted at about the temperature indicated in TABLE 1 at about 0.5 atm.
[0000]
TABLE 1
solvent
technique (bath temperature)
acetonitrile/reflux
concentration (stream of N 2 gas)
acetone
concentration (65° C.)
1,3-dioxolane/isopropanol
concentration (80° C.)
1,3-dioxolane/water
concentration (55° C.)
ethyl acetate
concentration (60° C.)
isopropanol
concentration (80° C.)
DMSO
antisolvent (water)
tetrahydrofuran
concentration (60° C.)
THF/methanol
antisolvent (hexanes)
Example 5
Crystalline Lestaurtinib Anhydrate
[0088] Hydrated crystalline lestaurtinib was heated between about 80° C. and 100° C. at about 760 mm Hg (1 atm) pressure. The product was stored in an environment having less than about 5% relative humidity.
Example 6
Lestaurtinib Crystalline Form 1
[0089] A mixture of EXAMPLE 2, EXAMPLE 2A, EXAMPLE 4, EXAMPLE 4A or a mixture thereof in ethanol, in which the example, or the mixture thereof, was partially soluble, was allowed to stand, with or without stirring, until Lestaurtinib Crystalline Form 1 formed.
Example 7
Crystalline Lestaurtinib Hemihydrate Hemitetrahydrofuranate
[0090] A solution of lestaurtinib in refluxing THF, in which the lestaurtinib was completely soluble, was treated with water until turbid, cooled, stored under darkness at ambient temperature for 24 hours and filtered.
[0091] It is meant to be understood that peak heights in a PXRD spectrum may vary and will be dependent on variables such as the temperature, size of crystal size or morphology, sample preparation, or sample height in the analysis well of the Scintag×2 Diffraction Pattern System.
[0092] It is also meant to be understood that peak positions may vary when measured with different radiation sources. For example, Cu-Kα 1 , Mo-Kα, Co-Kα and Fe-Kα radiation, having wavelengths of 1.54060 Å, 0.7107 Å, 1.7902 Å and 1.9373 Å, respectively, may provide peak positions that differ from those measured with Cu-Kα radiation.
[0093] The term “about” preceding a series of peak positions is meant to include all of the peak positions of the group which it precedes.
[0094] The term “about” preceding a series of peak positions means that all of the peaks of the group which it precedes are reported in terms of angular positions with a variability of ±0.1°.
[0095] For example, the phrase about 7.0°, 14.0°, 14.4°, 14.8°, 15.6°, 18.9°, 25.5°, 26.5° or 35.5° means about 7.0°, about 14.0°, about 14.4°, about 14.8°, about 15.6°, about 18.9°, about 25.5°, about 26.5° or about 35.5° and also 7.0°±0.1°, 14.0°±0.1°, 14.4°±0.1°, 14.8°±0.1°, 15.6°±0.1°, 18.9°±0.1°, 25.5°±0.1°, 26.5°±0.1° or 35.5°±0.1°.
[0096] As those skilled in the art will appreciate, numerous modifications and variations of the present invention are possible in view of the above teachings. It is therefore understood that within the scope of the appended claims, the invention can be practiced otherwise than as specifically described herein, and the scope of the invention is intended to encompass all such variations. | Crystalline lestaurtinib hydrates and crystalline lestaurtinib hemihydrate hemicetonitrileate and crystalline lestaurtinib hemihydrate hemitetrahydrofuranate, processes to reproducibly make them and methods of treating patients using them are disclosed. | 2 |
TECHNICAL FIELD
This invention relates to a continuous manufacturing process for insulated garage door panels and the like where outer metal skins contain insulating foam.
BACKGROUND OF THE INVENTION
Doors of the type used for closing a large opening in a building, such as a garage door, have long been manufactured using a plurality of substantially identical panels. The plurality of panels are typically hingedly connected together to permit relative hinging movement between adjacent panels when the door is moved between a closed vertical position and an open horizontal position. Such multi-panel doors, commonly referred to as sectional doors, often employ individual wooden panels which are appropriately hingedly connected at the adjacent horizontal edges thereof. Wooden panels are costly to manufacture, however, and result in the door being extremely heavy, particularly when the door is of large size. The weight of wooden sectional doors makes opening and closing of the door extremely difficult, even when an automatic operator is used.
In an effort to improve upon wooden sectional doors, panels which are rolled or formed from a tin sheet material, such as metal, fiberglass, or plastic have been used. These rolled or formed panels are necessarily provided with some form or irregular cross-section, such as a channel shaped cross-section, to provide the panels with sufficient strength and rigidity. Doors using formed or rolled panels have proved acceptable in some situations, but suffer from the distinct disadvantages that they are extremely heat conductive leading to thermal losses when used with an air-conditioned space.
Another improved door panel construction has been used having inner and outer thin sheet material skins and an insulating core, resulting in a construction which is light in weight, thermally insulated, and highly warp-resistant over relatively long spans. This improved construction is designed to be made by a continuous and automated "foamed-in-place" process where two cells of metal or vinyl material are uncoiled in a vertically spaced relationship, edge-formed to a desired configuration, and brought together at a foam-injecting station. Liquid polyurethane foam material is then placed in the lower skin at the foam-injecting station, and the skins are held in a spaced-apart relationship by a pressure conveyor while the foam cures. At the end of the pressure conveyor, the emerging continuous strip of door panel structure is cut transversely to desired lengths.
In the prior art foamed-in-place manufacturing process, wherein the two continuous rolls of panel skin material are used, the lower skin material is typically first rolled up on the edges to form a trough longitudinal in the direction of transport of the skin material. The unexpanded, liquid foam material is then applied in the center of the trough and spread evenly across the interior surface of the trough. Meanwhile, the upper skin material is suitably edge formed and transported to an opposing relationship with the trough-shaped lower skin material holding the expanding liquid foam material. The upper skin material, lower skin material and partially expanded foam enter a pressure conveyor which constrains the skins on all sides to enable dimensional integrity while the foam cures. At the end of the pressure conveyor, the foam is fully cured, and the adhesive characteristics of the foam maintain the structural integrity of the panel. It is known to incorporate longitudinal ornamental features such as ribs into panel skins through a continuous rolling process, at or near the edge forming step of the process.
The prior art continuous foamed-in-place door panel manufacturing process uses continuous rolls of material to form the upper and lower skins. A major disadvantage of this system is that the use of continuous skin materials prohibits the incorporation of intermittent transverse ornamental features such as "raised panels" into the skins. Such features can be practically incorporated into a skin only by processes such as stamping or embossing the skin where the skin is intermittently held stationary. It has not been practical to incorporate a step into the overall foamed-in-place manufacturing process where a continuous skin material can be maintained stationary on an intermittent basis in order to emboss or stamp a transverse ornamental feature.
Another problem in adapting transverse features to the foamed-in-place process arises from difficulty in handling the skins due to their fragility in the unmanufactured state. For example, once sheet steel is embossed with an ornamental feature, longitudinal or transverse, it cannot be rolled into a continuous roll without permanently kinking the sheet.
It is also believed to be impractical to adapt the continuous foamed-in-place process, where the timing of the foam material injection and pressure containment of the skins panel during foam curing is critical, to a stamping or embossing process "on the fly". On the fly stamping or embossing would involve embossing the transverse ornamental features on the sheet as it is removed from a roll and immediately prior to entering the portion of the process where foam is sandwiched between the upper and lower skins. A stamping or embossing process using a press requires that the material intermittently be held stationary for a given cycle time during which the stamping or embossing process is performed. Rotary embossers are also believed to be impractical, as well, due to the tendency of such embossers to leave undesirable surface defects ("oil-canning") on the embossed product.
The industry has been frustrated in attempting to adapt the continuous foamed-in-place panel manufacturing process to make panels having intermittent transverse ornamental features. Thus, it can be seen that a need has arisen for a continuous foamed-in-place door panel manufacturing process that enables the use of panel surfaces that include intermittent transverse ornamental features.
SUMMARY OF THE INVENTION
An improved continuous process for manufacturing foamed-in-place door panels enables the use of door skins having intermittent transverse ornamental features. The process includes the step of continuously connecting previously embossed discrete door skin segments end-to-end by means of flexible joints to form a string of skin segments. The string of skin segments is then conveyed to a foamable liquid injecting station where foamable liquid is injected between the string of skin segments and a continuous strip of second skin material. A thin film of polyethylene is then applied to the string of skin segments. The string of skin segments, polyethylene film, foamable liquid, and second skin material are then transported through a pressure conveyor during foaming of the foamable liquid. The use of discrete skin segments connected end-to-end by flexible joints allows the incorporation of intermittent transverse ornamental features into the skin segments. The polyethylene film provides a protective barrier for containing the foamable liquid in the event of a separated flexible joint.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete understanding of the invention and its advantages will be apparent from the Detailed Description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a perspective view of a garage door having door panels manufactured by the process of the present invention;
FIG. 2 is a partial perspective view of a first side of a door panel manufactured by the process of the present invention;
FIG. 3 is a partial perspective view of the second, other side of the door panel of FIG. 2;
FIG. 4 is a sectional view taken along lines 4--4 of FIG. 2;
FIG. 5 is a sectional view taken along lines 5--5 of FIG. 2;
FIG. 6 is a sectional view taken along lines 6--6 of FIG. 2;
FIGS. 7a and 7b illustrate in schematic fashion apparatus for carrying out the process of the present invention;
FIG. 8 is a schematic perspective view of the foamable liquid injecting station of the apparatus of FIGS. 7a and 7b;
FIG. 9 is a front view of a spreader roller used in the apparatus of FIG. 8; and
FIG. 10 is a partial perspective view of a continuous strip of door panel structure manufactured by the process of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring initially to FIG. 1, overhead sectional door 10 encloses an opening in building 12 defined by jambs 14 and 16 and header 18. Driveway 19 forms a lower edge of the opening. Door 10 includes four door panels 20 hingedly connected to each other and mounted on conventional track and rollers (not shown) within building 12 to enable the opening of door 10 by moving it from the horizontal position shown to an ovrhead position.
Each door panel 20 includes eight intermittent transverse ornamental features 22. The features 22 shown in FIG. 1 are known as a "raised panels" and are highly desirable for aesthetic reasons for incorporation into residential buildings. Features 22 duplicate the appearance of a popular pattern commonly used in the construction of traditional wooden garage doors where individual pieces of wood are used in a cabinet-like "raised panel" construction.
Referring now to FIGS. 2 and 3, door panel 20 includes a first skin 30 in which the features 22 are formed and which is utilized as the exterior surface of the door. Second skin 32 (FIG. 3) is used as the inner surface of the door panel and includes continuous longitudinal ribs 34. Ribs 34, visible from the interior of the enclosed space, primarily serve a structural purpose in stiffening second skin 32. Upper surface 36 and lower surface 38 of door panel 20 include a rabbett joint structure which allows an overlapped, weather-tight joint between the panels. Typically, the joints between the panels also include weather stripping and a rain channel not shown in FIGS. 2 and 3. The rain channel prevents dripping when the door is opened.
Referring now to FIGS. 4, 5, and 6, first skin 30 and second skin 32 substantially enclose a foam core 50, which provides insulation between the two skins. Intermittent transverse ornamental features 22 are embossed into first skin 30, as shown in FIGS. 5 and 6. First skin 30 is overlapped at edges 52 and 54. Second skin 32 is rolled to form upper surface 36 and lower surface 38 into the rabbett joint configurations such that second skin 32 is a substantially concave, trough-like structure. In addition, the second skin 32 is overlapped to form edges 56 and 58. In the preferred embodiment, edges 52 and 56 are separated by a small gap to prevent thermal conduction between first skin 30 and second skin 32. A gap is similarly provided between edges 54 and 58.
Referring now to FIGS. 7a and 7b, the door panels are manufactured in a continuous process beginning with a stack 60 of first skin segments 30 which have been previously embossed with the desired intermittent transverse ornamental features. Discrete first door skin segments 30 are laid end-to-end on a belt conveyor 62 and connected by a flexible tape joint 64 to form a string 66 of first skin segments 60. The string 66 is elevated by way of conveyor 68 in a gradual fashion to prevent distortion of string 66. An elevated conveyor 70 receives the string 66 at the end of conveyor 68.
Joint 64 is formed using a high strength, heat-resistant, fiber-reinforced tape overlaying at least the upper sides of the ends of first skin segments 60. Tape may also be applied to the under sides of the ends for enhanced joint strength. Joints 64 enable the discrete first skin segments 60 to be self-aligning in subsequent stages of the manufacturing process, such as roll mills 72, where guiding systems rigidly control the transport of the string 66. Roll mills 72 are provided to roll the edges 52 and 54 of first skin segments 30 as shown in FIGS. 4, 5, and 6 and are located along a portion of elevated conveyor belt 70. Oven 74 is provided to control the temperature of the first skin segments 30, and then a descending conveyor belt 76 lowers the string 66 of first skin segments 30 to a foamable liquid injecting station 78.
The material for second skin 32 is provided from a continuous roll 80 beneath elevated conveyor belt 70. Material from roll 80 passes through roll mills 82 where the rabbetted surfaces 36 and 38 as well as overlapped edges 56 and 58 are formed. Surfaces 36 and 38 are upwardly turned at roll mills 82 such that second skin material 32 forms a trough. Second skin material 32 then passes through an infrared oven 84 provided to control the temperature of second skin material 32. At the foamable liquid injection station 78, foamable liquid 86 is injected from a nozzle 88 into the trough formed by second skin material 32. Nozzle 88 is located beneath the descending conveyor belt 76. A polyethylene film 90 is applied by way of a spreader roller 92 to at least the joint portions of the string 66 of first skin segments 30 immediately before the string 66, second skin material 32, and foamable liquid 86 enter pressure roller 94. For ease of application, film 90 may be continuously applied as illustrated in the figures.
The speed of transport for the process and the length of pressure roller 94 are selected such that foamable liquid 86 is substantially cured at the end 96 of pressure roller 94. The door panel structure 98 (FIG. 7b) emerging from end 96 of pressure conveyor 94 is cut to length by flying shear 100 and stored in stack 102.
Referring now to FIG. 8, the foamable liquid injecting station 78 is illustrated in greater detail. Guidance rollers 110 are provided to precisely aim string 66 towards in-feed roller 112. Foamable liquid 86 rapidly expands once it is applied to second skin material 32. A roll 114 of the polyethylene film 90 is fixed above spreader roller 92. In the preferred embodiment, polyethylene film 90 has an adhesive coating that enhances the application of the film 90 to the string 66 of first string segments 30. As shown in FIG. 9, spreader roller 92 has left-handed spiral grooves 116 and right-handed spiral grooves 118 to spread the polyethylene film 90 evenly before application to string 66. Pressure roller 94 is configured to constrain string 66, lower skin material 32 and foamable liquid 86 in the configuration resulting in the crosssections shown in FIGS. 4, 5, and 6.
The apparatus shown in FIGS. 7a, 7b, and 8 is also usable in connection with the prior art manufacturing process wherein a continuous upper skin material is used as opposed to the segmented string of skin segments of the present invention. When used with the prior art process, upper skin material is fed onto elevated conveyor belt 70 from a roll 130 shown in FIG. 7a. It will be appreciated that the prior art process using roll 130 can only be used when panels having only longitudinal ornamental features, or no ornamental features, are desired.
The function of polyethylene film 90 is illustrated in FIG. 10. The foam joints 64 are intended to maintain the connections between discrete first skin segments 30 throughout the process, however, it has been found that occasionally a flexible joint 64 will separate in the process due to stresses placed on string 66 during the roll forming steps. The ability of the flexible joints 64 to separate under high stress is desirable from the standpoint of avoiding damage the discrete first skin segments 30. It is essential, however, that some provision be made for containing the foamable liquid in the vicinity of any gaps caused by separations of flexible joints 64. Otherwise, foamable liquid and the resulting foam would contaminate pressure conveyor 94 and require a shut-down of the process in order to clean the pressure conveyor. Thus, as shown in FIG. 10, polyethylene film 90 has contained foam 130 in gap 132.
The preferred manner of providing flexible joints 64 is by use of very high strength heat-resistant adhesive tape. It will be recognized, however, that the required flexibility and self-aligning characteristics of flexible joints 64 may be obtained by other means, such as flexible mechanical links using, for example, tabs formed on one end of the first string segments and registered holes on the other ends of the segments for flexible attachment of the first string segments.
Whereas the present invention has been described with respect to a specific embodiment thereof, it will be understood that various changes and modifications will be suggested to one skilled in the art and it is intended to encompass such changes and modifications as fall within the scope of the appended claims. | An improved continuous automated method of manufacturing insulated door panels is provided. The process includes a step of continuously connecting discrete first skin segments end to end by means of flexible joints to form a string of first skin segments and then conveying the string to a foamable liquid injecting station. In a preferred embodiment, a polyethylene film is applied to the string in order to contain foamable liquid in event of a gap caused by separation of a flexible joint. | 1 |
BACKGROUND
[0001] 1. Technical Field
[0002] The present invention relates to a surface illumination device, particularly to a display surface illumination device.
[0003] 2. Related Art
[0004] In the smartphone, the tablet computer, an electronic book reader, and the like, an icon is lighted in a position of a switch, and the position and a type of the switch is expressed by the icon.
[0005] Patent Document 1: Japanese Unexamined Patent Publication No. 2001-243822
SUMMARY
[0006] One or more embodiments of the present invention provides a surface illumination device that can smoothly or clearly express the edge of the display unit expressed by the desired drawing pattern, a graphic, a character, or the like.
[0007] In accordance with one or more embodiments of the present invention, a surface illumination device includes: a light source; a light guide plate that emits light, which is introduced from the light source, from a display region of a light-emitting surface; and plural deflection patterns that are formed in the display region in at least one of the light-emitting surface of the light guide plate and an opposite surface to the light-emitting surface, wherein the display region is one in which a certain drawing pattern is expressed by a set of the deflection patterns, and the plural deflection patterns are arrayed along an edge of the drawing pattern so as to rim the drawing pattern. As used herein, the drawing pattern includes the graphic, the pattern, and the character, but the drawing pattern is not limited to one in which a meaning can be recognized.
[0008] In the surface illumination device according to one or more embodiments of the present invention, the plural deflection patterns are arrayed along the edge of the drawing pattern so as to rim the drawing pattern. Therefore, the display unit including the set of deflection patterns can clearly be expressed, and the edge of the display unit can be smoothened.
[0009] In the surface illumination device according to one or more embodiments of the present invention, the deflection patterns that rim the drawing pattern are arrayed at constant intervals along the edge of the drawing pattern. Accordingly, the edge of the display unit can become luminous with homogeneous luminance.
[0010] In a surface illumination device according to one or more embodiments of the present invention, the deflection pattern is inscribed in a place that becomes a corner at the edge of the drawing pattern. Accordingly, the corner of the drawing pattern is not rounded, but the sharp display unit can be produced.
[0011] In a surface illumination device according to one or more embodiments of the present invention, the deflection pattern is inscribed in a place that becomes an inflection point at the edge of the drawing pattern. At this point, it is assumed that the inflection point includes a connection point of the straight line and the curve. Accordingly, the drawing pattern expressed by the display unit can easily be understood.
[0012] In a surface illumination device according to one or more embodiments of the present invention at least the three deflection patterns including the deflection patterns located at both ends are inscribed in the edge of the drawing pattern in a curve portion located between two inflection points at the edge of the drawing pattern. Accordingly, the curve can easily be expressed at the edge of the display unit.
[0013] In accordance with one or more embodiments of the present invention, a mobile phone that has transmission and reception functions, includes the surface illumination device in order to optically display a certain drawing pattern. In one or more embodiments of the present invention, the surface illumination device according to one or more embodiments of the present invention is used in mobile phones such as the smartphone. Accordingly, the display such as the icon can be clarified.
[0014] In accordance with one or more embodiments of the present invention, an information terminal that has an information processing function includes the surface illumination device in order to optically display a certain drawing pattern. In one or more embodiments of the present invention, the surface illumination device according to one or more embodiments of the present invention is used in information terminals such as a mobile computer, the tablet computer, an electronic diary, and an electronic dictionary. Accordingly, the display such as the icon can be clarified.
[0015] The scope of the present invention includes variations made by the combination of components.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1(A) is a plan view of a smartphone. FIG. 1(B) is a plan view of a surface illumination device incorporated in the smartphone in FIG. 1(A) .
[0017] FIG. 2(A) is a schematic sectional view of a conventional surface illumination device together with one enlarged deflection pattern. FIG. 2(B) is a plan view of a display unit (deflection pattern region) provided in a conventional light guide plate.
[0018] FIG. 3 is a view illustrating a specific design of the display unit.
[0019] FIG. 4 is an underlying pattern layout drawing that determines a deflection pattern array becoming a certain drawing pattern.
[0020] FIG. 5(A) illustrates a handset-shaped display unit that is cut out from the pattern layout drawing in FIG. 4 . FIG. 5(B) is a partially enlarged view of a Q portion in FIG. 5(A) .
[0021] FIGS. 6(A) and 6(B) are a plan view and a sectional view illustrating a surface illumination device according to one or more embodiments of the present invention.
[0022] FIGS. 7(A) and 7(B) are a plan view and a sectional view of a deflection pattern.
[0023] FIG. 8 is a view illustrating the deflection patterns arrayed at constant intervals along an edge of the display unit.
[0024] FIG. 9 is a schematic diagram illustrating the deflection patterns disposed in the display unit having a corner.
[0025] FIG. 10 is a schematic diagram illustrating the deflection patterns disposed in the display unit having a curve and an inflection point.
[0026] FIG. 11(A) is a partially enlarged view of the Q portion in FIG. 5(A) . FIG. 11(B) is a view illustrating a deflection pattern layout in which a deflection pattern layout in FIG. 11(B) is corrected.
DETAILED DESCRIPTION
DESCRIPTION OF SYMBOLS
[0000]
11 smartphone
12 liquid crystal display screen
13 icon
16 light guide plate
17 light source
18 deflection pattern
19 display unit
31 surface illumination device
T inflection point
[0036] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In 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 obscuring the invention. FIG. 1(A) shows a smartphone 11 having an icon 13 displayed below a liquid crystal display screen 12 . When the icon 13 is pressed by a finger, a switch 14 provided beneath the icon 13 is turned on to switch a function of the smartphone 11 .
[0037] FIG. 1(B) illustrates a surface illumination device 15 for the display, which is incorporated in a lower portion of the smartphone 11 in FIG. 1(A) . FIG. 2(A) illustrates a schematic section of the surface illumination device 15 . The surface illumination device 15 includes a light guide plate 16 and a light source 17 . The light guide plate 16 is molded using a transparent material, such as a polycarbonate (PC) resin and a polymethylmethacrylate (PMMA) resin, which has a high refractive index. The light source 17 is a minute light source (a point light source) in which an LED is used, and the light source 17 is disposed while a light exit window is opposed to one (light incident end face 16 a ) of end faces of the light guide plate 16 . Many minute prism deflection patterns 18 are formed in a lower surface (sometimes an upper surface) of the light guide plate 16 , and an icon-shaped display unit 19 is constructed by a set of deflection patterns 18 as illustrated in FIG. 2(B) . The deflection patterns 18 are arrayed in an arc shape about a point near the light source 17 , and extend in directions along the arc about the point. A thin, flexible light guide sheet is used as the light guide plate 16 in the case that the switch 14 is disposed beneath the display unit 19 . Although the icon 13 and the display unit 19 are expressed by a character “A” in FIGS. 1(A) and 1(B) , actually design marks such as a magnifying glass and a handset are frequently used as illustrated in FIG. 3 .
[0038] When the light source 17 emits light in the surface illumination device 15 , the light incident to the light guide plate 16 from the light incident end face 16 a is guided in the light guide plate 16 while totally reflected by the upper surface, the lower surface, and both side surfaces of the light guide plate 16 . When the light guided in the light guide plate 16 reaches the display unit 19 as illustrated in FIG. 2(A) , the light is totally reflected by a deflection reflecting surface 18 a of the deflection pattern 18 . In the light totally reflected upward by the deflection reflecting surface 18 a, the light incident to the upper surface (a light-emitting surface 16 c ) of the light guide plate 16 at an angle smaller than a total reflection critical angle is transmitted through the light incident end face 16 a to emit upward (the light is transmitted while refracted by the deflection pattern 18 in the case that the deflection pattern 18 is provided in the light-emitting surface 16 c ). As a result, the icon-shaped light is emitted, and the icon 13 of the smartphone 11 is seen shiny.
[0039] A display unit 19 on which the icon is displayed is constructed by a set of minute deflection patterns 18 . Additionally, there is a restriction to a position where the deflection pattern 18 is disposed in order to homogeneously shine the display unit 19 . Therefore, even if the design mark to be used as the icon exists, it is difficult that the design mark having the smooth edge is expressed by the deflection patterns 18 as illustrated in FIG. 2(B) . Particularly, for the small icon, it is necessary that the design mark be expressed with a small number of deflection patterns 18 . Therefore, the smooth design mark is hardly expressed.
[0040] Even in the simple design mark, because the deflection patterns 18 are arrayed into the arc shape about the point near the light source 17 , for example, it is difficult to smoothly express even the edge on the straight line.
[0041] When the deflection patterns 18 are positioned according to the design mark after the design mark is fixed, it is necessary to homogeneously shine the whole display unit, and it is necessary that a layout of the deflection patterns 18 be designed in each case such that the edge is smoothened. Even if a computer aids, it is difficult to homogeneously shine the whole display unit, and it is difficult that the layout of the deflection patterns 18 is designed in each case such that the edge is smoothened. Therefore a delivery time is lengthened, or cost increases.
[0042] For this reason, actually a large-area deflection pattern layout that can homogeneously be shined is used as illustrated in FIG. 4 . This is used in a backlight surface illumination device. The layout of the deflection patterns 18 that becomes the desired design mark are fixed as if the desired design mark is cut out from the pattern layout in FIG. 4 . FIG. 5(A) illustrates a handset design mark that is taken out from the pattern layout in FIG. 4 . Although the pattern layout drawing has the area identical to that of the light guide plate, FIG. 4 illustrates only part of the pattern layout drawing. Accordingly, in FIG. 4 , a distribution of the deflection patterns 18 is coarser than that in FIG. 5(A) . The light source 17 is located on the left side of the pattern layout in FIG. 4 .
[0043] FIG. 5(A) illustrates the handset design mark that is cut out from the pattern layout in FIG. 4 , and FIG. 5(B) is an enlarged view illustrating a Q portion in FIG. 5(A) . In the layout of the deflection patterns 18 in FIG. 5 , an edge of the design mark is not smoothened when the design mark is looked closely at. As can be seen from FIG. 5(B) , the deflection pattern 18 is lacked on the edge at the right side, and a place where the edge is recessed is periodically seen. At the upper edge, the deflection patterns 18 project like a spike to form a zigzag shape. The design mark is constructed only by the straight lines in FIG. 5(A) . However, the zigzag edge becomes more apparent for a drawing pattern including a diagonal line or a smooth curve.
[0044] FIG. 6(A) is a plan view of a surface illumination device 31 according to one or more embodiments of the present invention. FIG. 6(B) is a sectional view of the surface illumination device 31 . Because the surface illumination device 31 has a structure similar to that of the surface illumination device 15 in FIGS. 1(B) and 2(A) , the component identical to that of the surface illumination device 15 is designated by the identical symbol, and the description is omitted. The deflection pattern 18 constituting the display unit 19 is generally formed into a triangular prism shape, particularly a right triangular shape as illustrated in FIG. 7(A) . Alternatively, the deflection pattern 18 may be formed into a shape in which a deflection reflecting surface 18 a is curved as illustrated in FIG. 7(B) .
[0045] The display unit 19 of the surface illumination device 31 is constructed as illustrated in FIG. 8 . An alternate long and short two dashes line in FIG. 8 indicates an edge of a drawing pattern displayed on the display unit 19 . The deflection patterns 18 are arrayed at constant intervals along the edge of the display unit 19 .
[0046] In the case that the drawing pattern has a corner, an end of the deflection pattern 18 is located at each corner as illustrated in FIG. 9 . Therefore, the drawing pattern having the corner is prevented from being seen rounded.
[0047] In the case that the edge of the drawing pattern is a curve, as illustrated in FIG. 10 , the deflection pattern 18 is necessarily disposed at an inflection point T where a curved direction of the curve is inverted. In one curve, for example, a substantially arc-like curve between the inflection points, at least three, and according to one or more embodiments of the present invention, at least five deflection patterns 18 including the deflection patterns 18 located the inflection points T at both ends are disposed at the edge of the drawing pattern. Therefore, the curve is prevented from looking like a polygonal line.
[0048] FIG. 11(A) is an enlarged view illustrating the Q portion in FIG. 5(A) (identical to FIG. 5(B) ). In (a part of) the display unit 19 , recesses are generated at the right and left edges to lack in sharpness. In FIG. 11(B) , the deflection patterns 18 are rearranged so as to be linearly arrayed along the right and left edges of the display unit 19 .
[0049] Although not illustrated, the deflection patterns 18 are not rearranged, but the deflection patterns 18 may linearly be arrayed by adding the deflection pattern 18 to each place where the edge is retreated in the display unit 19 in FIG. 11(A) . The positions of the deflection patterns 18 inside the display unit 19 also change in FIG. 11(B) . On the other hand, the positions of the inside deflection patterns 18 do not change in the method for adding the deflection pattern 18 .
[0050] In the display unit 19 in FIG. 11(B) , the upper edge is formed into a zigzag shape. Alternatively, the upper edge may be formed flat like the lower edge.
[0051] 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 surface illumination device has a light source, a light guide plate that has a light-emitting surface and an opposite surface opposite to the light-emitting, wherein the light guide plate emits light introduced from the light source from a display region of the light-emitting surface, and a plurality of deflection patterns that are formed in the display region in at least one of the light-emitting surface and the opposite surface. The display region has a certain drawing pattern expressed by a set of the deflection patterns. Some of the plurality of deflection patterns are arrayed along an edge of the certain drawing pattern so as to rim the certain drawing pattern. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to uninterrupted power supply (UPS) apparatus and, more particularly, to a power factor corrected UPS maintaining integrity of the connection from power line neutral to an output load terminal.
[0003] 2. Description of the Prior Art
[0004] UPS systems are now widely used to provide a secure supply of power to critical loads such as computers, so that if the line voltage varies or is interrupted, power to the load is maintained at an adequate level and is not lost. The UPS conventionally comprises a rectifier circuit for providing a DC voltage from the AC power lines; an inverter for inverting the DC voltage back to an AC voltage corresponding to the input, for delivery to the load; and a battery and a connection circuit for connecting battery power to the input of the DC to AC inverter, so that when reliable AC power is lost the delivery of AC power to the load is substantially unaffected. In such an UPS, it is highly desirable to maintain an uninterrupted neutral from the commercial AC utility power to each component circuit and to the load, e.g., in order to eliminate shock hazards. Because of the inherent nature and mode of operation of typical UPS systems, conventional UPS designs did not maintain the integrity of the neutral through the processing circuitry, requiring some type of isolation means such as isolation transformer to re-establish the neutral at the load. U.S. Pat. No. 4,935,861, assigned to the assignee of this invention, provides an UPS wherein the electrical continuity of an electrical conductor is maintained from one terminal of the AC utility through to one of the load terminals, without any isolation means being required.
[0005] The problem with maintaining integrity of the neutral is further complicated in a UPS having a power factor correction circuit. The task of connecting the battery to neutral is simple in a power supply unit without a PFC circuit, such as shown in U.S. Pat. No. 4,823,247. But as is well known, there are important reasons for incorporating power factor correction (PFC) into an UPS. And, the incorporation of such a PFC circuit imposes additional difficulties upon the goal of maintaining integrity of a neutral connection from the power line to the load. A design for achieving an uninterrupted power supply system having a PFC circuit is disclosed in U.S. Pat. No. 4,980,812, also assigned to the assignee of this invention.
[0006] It is recognized that maintaining the integrity of the neutral in an UPS offers advantages of lower cost, due to lack of need for isolation means, and higher reliability. Because of the design criterion of an undisturbed neutral, an UPS with a PFC circuit has heretofore required three converters. As seen in FIG. 1, such a prior art apparatus contains a converter as part of the power factor correction circuit, the output of which provides DC on a positive high voltage (HV) rail and independent negative HV rail respectively relative to the neutral line. The DC-AC inverter is necessarily a second converter, and, a third converter circuit has been necessary to connect the DC from the battery to the HV rails. Prior art attempts to combine the battery converter with the PFC converter have always resulted in either an isolated UPS, wherein the neutral is not maintained, or some circuit arrangement for connecting the DC output of the battery into an AC voltage which could be utilized by the AC to DC converter portion of the PFC circuit. For safety reasons, it is desirable to effectively connect the battery to the neutral, which leaves an unfulfilled need for an efficient and reliable manner of translating the battery output to the HV rails. The design solution of having a third converter of some different kind, or the option of using an isolation transformer, both have obvious disadvantages. The problem is thus how to provide that the converted output from the PFC circuit, as well as the battery output, can be independently loaded and still balanced around neutral to the plus and minus HV rails without using a separate converter of some sort for each. Stated differently, the problem for which a solution has not heretofore been known is how to connect the battery to the HV rails utilizing the PFC converter, while effectively maintaining a connection from the battery to neutral.
SUMMARY OF THE INVENTION
[0007] It is an object of this invention to provide a power factor corrected UPS which maintains neutral integrity from the input of the UPS to an output terminal to which the load is connected, the UPS device having a simple and efficient circuit for connecting the battery to the converter of the PFC circuit, whereby whenever the battery provides output power due to deterioration of the utility line voltage, battery voltage is converted through the PFC converter and delivered to the high voltage rails. The UPS achieving this object provides an uninterrupted neutral from its input connection to the AC power line through to an output terminal for connection to the load, balances the battery around neutral, and achieves supply of the battery power independently to the high voltage rails without the need of an independent battery to HV rail converter, or the need for any isolation means.
[0008] In a first embodiment, a four diode-two capacitor circuit is used to connect the battery to the PFC converter. During normal operation when the UPS is drawing power from the utility line, the battery is balanced around neutral and is maintained no more than one forward diode drop away from neutral. By using a battery with a voltage less than one-half of the peak of the incoming AC voltage, the PFC circuit is substantially unaffected so that power factors greater than 0.9 can be achieved. During loss of AC input, when the UPS runs on battery, switching elements of the PFC converter are independently turned on and off, enabling conversion of the battery voltage through the PFC converter circuitry to the HV lines. In a second, preferred embodiment, one terminal of the battery is connected directly to neutral, and the other terminal is connected through a normally open switch and a diode to the converting circuit. The switch is closed when low AC power line voltage is sensed. Both embodiments thus enable elimination of a separate converter for the battery while preserving the advantages of prior art power factor corrected UPS devices maintaining integrity of the neutral connection from input to load.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIG. 1 is a simplified block diagram showing the primary components of a prior art power factor corrected UPS.
[0010] [0010]FIG. 2 is a simplified circuit diagram of a power factor corrected UPS with neutral integrity, and illustrating the problem of connecting the battery to the HV rails without the aid of a converter dedicated to the battery.
[0011] [0011]FIG. 3 is a circuit diagram showing a first embodiment of the improved connection circuit of this invention, whereby the battery is connected to the converter of the PFC circuit while maintaining the battery balanced around neutral.
[0012] [0012]FIGS. 4A and 4B are circuit diagrams illustrating a cycle of operation when the UPS of FIG. 3 is drawing power from the AC input, and the line or energized AC input terminal is positive relative to the neutral terminal.
[0013] [0013]FIGS. 5A and 5B are circuit diagrams illustrating a cycle of operation when the UPS of FIG. 3 is drawing power from the AC input, and the line or energized AC input terminal is negative relative to the neutral terminal.
[0014] [0014]FIGS. 6A and 6B illustrate operation of the improved UPS circuit of FIG. 3 during a condition of unacceptable AC input and UPS battery operation.
[0015] [0015]FIG. 7A is a circuit diagram of a preferred embodiment of the invention, wherein one terminal of the battery is connected directly to neutral.
[0016] [0016]FIGS. 7B and 7C are circuit diagrams illustrating a cycle of battery-driven operation for the circuit of FIG. 7A.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] Referring now to FIG. 2, there is shown a circuit diagram of a typical power factor corrected UPS with an uninterrupted neutral from input to output. The AC input is connected to the UPS at two input terminals, one of which is marked “line” and the other of which is marked “neutral.” The neutral line is connected by an uninterrupted conductor to one of two output terminals, across which AC output power is delivered. The AC input signal is connected across a first capacitor Cl. The line terminal is connected to rectifier diodes D 1 and D 2 . D 1 is in series with inductor L 1 , the other side of L 1 being connected through switching transistor Q 1 to neutral. D 2 is connected in series with inductor L 2 , the other side of L 2 being connected through switching transistor Q 2 to neutral. The input terminals 31 , 32 are driven by switch control means 33 such as illustrated in FIG. 1 of U.S. Pat. No. 4,980,812, incorporated herein by reference. Transistors Q 1 and Q 2 of FIG. 2 correspond to transistors 86 and 88 seen in FIG. 1 of the referenced patent. Transistors Q 1 and Q 2 are driven in such a manner as to achieve a power factor close to 1.0, and to maintain needed voltage across C 2 and C 3 . Inductor L 1 is also connected through diode D 3 and capacitor C 2 to neutral; and inductor L 2 is connected through diode D 4 and capacitor C 3 to neutral. When Q 1 is turned off after it has been conducting, current is passed through L 1 and D 3 to charge capacitor C 2 , maintaining positive voltage on the +HV rail 35 . Likewise, when Q 2 is turned off after having been turned on during a negative swing of the line voltage, current from inductor L 2 passes through diode D 4 and charges capacitor C 3 , maintaining negative voltage on high V rail 36 .
[0018] Still referring to FIG. 2, HV rails 35 and 36 have connected therebetween transistor switches Q 3 and Q 4 in series, which are driven at input terminals 38 and 39 by a reference signal in a well known manner, so as to alternately switch on during respective half cycles of positive and negative going voltage. Diode D 5 is placed across transistor Q 3 , and diode D 6 is placed across transistor Q 4 . The switched voltage appearing at the node between transistors Q 3 and Q 4 is connected to filtering inductor L 3 , and the AC output which appears across capacitor C 4 drives the load 40 connected between line out and neutral.
[0019] Battery 30 is shown in FIG. 2, having its negative terminal connected to neutral, but its positive terminal unconnected. The longstanding problem in the art, which this invention meets, is how to connect the battery in such a way as to enable generation of the plus and minus HV rails from such battery at the time of AC input line failure. What is needed is a simple but reliable circuit which can utilize the inductor and switching components of the PFC circuit, i.e., inductors L 1 and L 2 , and transistors Q 1 and Q 2 .
[0020] Referring now to FIG. 3, there is shown an improved circuit which connects the battery to converter elements of the power factor correction circuit of FIG. 2. In addition to the circuit components illustrated in FIG. 2, there is illustrated a battery 30 which is tied at its plus terminal to neutral through diode D 9 , and at its minus terminal to neutral through diode D 10 . Bypass capacitors C 5 and C 6 bridge diodes D 9 and D 10 respectively, and are chosen to have a large capacitance with respect to the switching frequency of switches Q 1 and Q 2 , which is determined by control circuit 33 . The positive terminal of the battery is also connected through D 7 to a node between D 1 and L 1 , and the negative terminal of the battery is connected through diode D 8 to a node between D 2 and L 2 . Instead of connecting Q 1 and Q 2 to neutral as in FIG. 2, the emitter of Q 1 is connected to the negative terminal of the battery, while the collector of Q 2 is connected to the positive terminal of the battery. Thus, in terms of extra circuit components, the improved circuit comprises the simple addition of four diodes and two high frequency bypass capacitors. During normal operation the battery is balanced around neutral, and never gets more than a forward biased diode drop away from neutral, e.g., about one-half to three-fourths volts. By utilizing a battery that has a voltage less than one-half the peak of the incoming AC voltage, the power factor correction circuit operates over a sufficiently long portion of each cycle to achieve a power factor greater than 0.9.
[0021] Referring now to FIGS. 4A and 4B, there are illustrated circuit diagrams showing the equivalent circuit operation under conditions where there is a good input on the AC line, and the input voltage is positive and greater than battery voltage. In FIG. 4A, Q 1 is illustrated in an on or closed switch position, and in FIG. 4B is illustrated in an off, or open switch position. Note that Q 1 is turned on only when the voltage peak is greater than the battery voltage, such that D 7 is reversed biased. In this condition, as illustrated in referenced U.S. Pat. No. 4,980,812, capacitor C 2 is shunted by Q 1 and current builds up in inductor L 1 . When Q 1 opens, as shown in FIG. 4B, L 1 acts as a current generator and pumps current into capacitor C 2 , building up the DC voltage thereacross. FIGS. 5A and 5B show the equivalent circuit diagram when the line terminal is negative and the voltage exceeds the battery voltage. In a similar fashion, when Q 2 is closed and thus shunts C 3 , current builds up through L 2 . When Q 2 is opened, current is pumped from L 2 into capacitor C 3 , thereby generating a negative voltage across C 3 with respect to neutral. These respective operations generate the positive and negative HV rails indicated in FIG. 3, in a manner that is substantially unchanged with respect to the embodiment of U.S. Pat. No. 4,980,812. During this typical cycle of operation, forward biased diode D 10 connects current through Q 1 while it is closed, and forward biased diode D 9 is in series with switch Q 2 when it is closed, with the result that the improved circuit has no appreciable impact on the operation of the PFC conversion. During the positive line voltage swing, the negative terminal of the battery is tied to neutral through D 10 ; during the negative line voltage swing, the positive terminal of the battery is tied to neutral through D 9 .
[0022] Referring now to FIGS. 6A and 6B, there are illustrated the effective circuit diagrams for the UPS circuit of this invention during loss of AC input, i.e., at any time when UPS load is being supplied by the battery. During this time, the improved switching circuit acts to connect the battery to alternately charge C 2 and C 3 so as to maintain the same plus and minus high voltage rails. During such battery back up operation, switches Q 1 and Q 2 are turned on and off independently, by switch control 33 .
[0023] When the AC source voltage drops to an unacceptable level, switch control 33 operates to drive Q 1 and Q 2 through on-off cycles, at a duty cycle as required to provide a regulated output. Note that each of Q 1 and Q 2 can be switched independently, as may be required for an unbalanced load (not shown unbalanced). Q 2 is held off (open) while C 2 is charged, and Q 1 is held off while C 3 is charged.
[0024] During the period of time that Q 2 is held off, Q 1 is first switched on and then switched off. FIG. 6A shows Q 2 off and Q 1 switched on. Under these circumstances, current flows from the battery through diode D 7 , inductor L 1 , and back through switch Q 1 to the negative terminal of the battery, building up current flow in inductor L 1 . At the same time, remaining current through L 2 is discharged through diode D 9 , diode D 10 , capacitor C 3 and diode D 4 . When Q 1 is turned off (FIG. 6B), the build up of current is passed through diode D 3 into capacitor C 2 , charging it positively with respect to neutral. The current through C 2 returns through diode D 9 . At the same time, current from battery 30 goes around the outer loop of the circuit shown, i.e., through D 7 , L 1 , D 3 , C 2 , C 3 , D 4 , L 2 and D 8 . Following this, the sequence is reversed such that Q 1 is turned off, and Q 2 is alternatingly turned on and off, resulting in the reverse operation which builds up the negative voltage across capacitor C 3 . During the battery supply of the output voltage, if capacitor C 2 and C 3 are loaded in a balanced manner, and if C 5 and C 6 have large capacitance for the switching frequency, then the voltage across each of capacitors C 5 and C 6 is held substantially constant and has a value of approximately one-half the voltage of the battery. To the extent that C 2 and C 3 loading becomes unbalanced, the ratio of the voltages across C 5 and C 6 likewise is unbalanced.
[0025] Referring now to FIG. 7A, there is shown a preferred circuit. In this embodiment, battery 30 has one terminal (illustrated as the negative terminal) connected to neutral. The other terminal is connected through switch S 1 to D 7 . Switch S 1 is normally open, but is closed by control 33 whenever low line voltage is detected, in a conventional manner. Compared to FIG. 3, diode D 10 and capacitor C 6 are eliminated, and switch S 1 is added. FIGS. 7B and 7C illustrate the circuit action when the load is battery-driven. In FIG. 7B, each of switches Q 1 and Q 2 are closed, such that current flows from battery 30 to each inductor L 1 , L 2 . In FIG. 7C, Q 1 and Q 2 are each switched open, so that current flows from L 1 to C 2 , and from L 2 to C 3 . In this embodiment as well, switch control 30 can drive Q 1 and Q 2 independently when the UPS is in the battery-driving mode due to low source AC voltage.
[0026] Both the preferred embodiment of FIG. 7A and the embodiment of FIG. 3 illustrate a DC to AC converter (utilizing transistors Q 3 , Q 4 ), for providing uninterrupted AC output. However, the invention also applies to a supply for providing a DC output, such that no DC to AC inverter is utilized. Thus, in general, the invention comprises an output circuit between the HV rails and the output terminals.
[0027] There is thus illustrated a very simple, inexpensive and reliable circuit which achieves the object of connecting the battery to an UPS having an uninterrupted neutral from input to output, the battery connection being made in such a way as to utilize the PFC circuit for conversion of the battery voltage during times when the battery is supplying output load. At the same time, the circuit ties one terminal of the battery to neutral, or holds the battery balanced around neutral, and does not adversely affect performance of the PFC circuit. The invention thus achieves the object of allowing the battery to be connected to neutral at all times, while utilizing the PFC circuit to convert the battery output to the HV lines at the time of AC power source failure. | An uninterrupted power supply (UPS) device with uninterrupted neutral from input to output utilizes the same converter for converting rectified AC power and battery power to positive and negative high voltage (HV) rails. A simple circuit is utilized for connecting the battery to the conversion components of the PFC circuit without adverse affect on the performance of the PFC circuit, and while holding the battery substantially connected to neutral. In a first embodiment, the circuit comprises a simple combination of four diodes and a pair of high pass capacitors arranged so that in both power line and battery supply modes the battery is balanced around neutral. In a second, preferred embodiment, one terminal of the battery is connected directly to neutral. | 8 |
FIELD OF THE INVENTION
[0001] This invention relates to mining technology and a method for the processing of recovered bitumen bearing oil sands from the earth. More particularly, the invention relates to a mobile system of equipment for increasing the efficiency of the ore mining operation.
BACKGROUND OF THE INVENTION
[0002] The Northern Alberta Tar Sands are considered to be one of the world's largest remaining oil reserves. The tar sands are typically composed of about 70 to about 90 percent by weight mineral solids, including sand and clay, about 1 to about 10 percent by weight water, and a bitumen or oil film, that comprises from trace amounts up to as much as 21 percent by weight. Typically ores containing a lower percentage by weight of bitumen contain a higher percentage by weight of fine mineral solids (“fines”) such as clay and silt.
[0003] Unlike conventional oil deposits, the bitumen is extremely viscous and difficult to separate from the water and mineral mixture in which it is found. Generally speaking, the process of separating bitumen from the tar sands comprises six broad stages. 1) Initially, the oil sand is excavated from its location and passed through a crusher or comminutor to comminute the chunks of ore into smaller pieces. 2) The comminuted ore is then typically combined with hot process water to aid in liberating the oil. The combined tar sand and hot water is typically referred to as a “slurry”. Other agents, such as flotation aids may be added to the slurry. 3) The slurry is then passed through a “conditioning” phase in which the slurry is allowed to mix and dwell for a period to create froth in the mixture. The term “conditioning” generally refers to a state whereby the slurry is sufficiently mixed and aerated that a commercially viable amount of the bitumen has left the mineral component to form an oily film over the bubbles in the slurry. 4) Once the slurry has been conditioned, it is typically passed through a series of separators for removing the bitumen froth from the slurry. 5) After the slurry has been sufficiently processed to remove the maximum practical amount of bitumen, the remaining material, commonly known as the “tails”, is typically routed into a tailing pond for separation of the sand and fines from the water. Due to the time required to clarify the tailings water, the process requires the continual addition of fresh water. 6) The separated bitumen and water is then delivered to a secondary extraction process that further removes mineral and water content and provides a diluted bitumen product for delivery to an upgrader that converts the bitumen into a commercially usable product.
[0004] It has been recognized for a long time that, since the bitumen comprises a relatively small percentage by weight of the ore initially extracted, separation of the mineral content from the ore as soon as possible after excavation would lead to the most efficient and cost effective mining process. It has also been recognized that it would be useful to immediately recycle the process water used to create the slurry rather than the current requirement of continually using fresh water due to the slow process of clarifying tailings water. While these advantages have been known, to date there has been no commercially viable method of extracting the mineral content soon after excavation and recycling the process water. Generally, the sand and fines settle out of the tails at different rates with the fines taking a long time to settle out. This results in a tailings pond comprised of a sand deposit, a suspension of fines and water, and a thin layer of clarified water on the top of the tailings pond. While the thin layer of clarified water is clean enough that it may be siphoned off and recycled as process water, the bulk of the water remains trapped in the suspension. Furthermore, as settling progresses, the settled fines trap a significant percentage by weight of water. The net result has been extensive tailings ponds that require significant containment structures and associated ongoing maintenance as well as increasing transportation costs as the tails must be transported to new tailings deposition sites as existing ponds are filled. Handling the tails and transporting them to available tailings ponds has become a difficult and expensive logistical problem in mining the oil sands. Additionally, a large volume of water is tied up in existing ponds, necessitating a large ongoing demand for fresh process water.
[0005] Over the years, a variety of methods have been used to process and transport the sand from the excavation site. Initially, oil sand excavation and transport were completely mechanical via conveyor belts extending from the mine face to a large facility for processing the mined ore. As mining progressed the conveyors lengths were increased to transport ore from the receding mine face to a large processing facility. The use of conveyors led to many difficulties including high energy costs and mechanical breakdown which led to work stoppage. As mining continued, the use of conveyors to transport the ore over extended distances became unworkable.
[0006] Large ore trucks were instituted to replace the conveyor system for transporting ore from the mine face to the processing facility. The ore trucks, however, are expensive to purchase and operate and often create inefficiencies in the production process.
[0007] As described in Canadian Patent No. 2,029,795, it was determined that it was preferable to deliver the ore by truck from the mine face to an intermediate site where the ore would be crushed and combined with hot process water at a slurry preparation facility to create a pumpable slurry for transport through a pipe. This “hydro-transport” process served the dual purpose of efficiently transporting the slurry from an intermediate site relatively near the mine face to the large processing facility and allowing time for the slurry to be sufficiently conditioned on route. Provided the hydro-transport was over a sufficiently large enough distance that the dwell time in the pipe was sufficiently long, typically at least 1 kilometre, the slurry would arrive at the processing facility already conditioned and ready for separation. Thus, the previously required separate conditioning step could be omitted from the process.
[0008] While the hydro-transport solved some of the difficulties with transporting the ore from the mine site face to the separation facility, it did not solve the long term need to reduce the mechanical transport of large volumes of mined oilsand from the mine face to the intermediate site. As will be appreciated, continual excavation results in the active mine site face being located further and further from the crusher and slurry preparation facility. Solutions to date have typically relied on constructing longer conveyor belts to transport the ore, or use additional trucks, to move the ore from the mine face to the slurry facility at the intermediate site. Though these solutions provide temporary relief, they do not solve the inefficiency of transporting the mineral component further than required.
[0009] One concept was to do away with the transport step completely by locating all of the ore processing machinery near the mine face. An example of this concept is disclosed in Canadian Patent No. 2,092,121 and Canadian Patent No. 2,332,207. These references disclose a single mobile excavator and bitumen extraction facility, commonly referred to as a tar sand combine, that follows the mine face as digging progresses. This solution is not ideal as it requires the continuous transport of a large amount of extremely heavy machinery and water including a slurry preparation facility. In addition, connections to the hydro-transport pipeline and process water supply line must be continuously extended as the combine advances. Further, some embodiments suggest separating the mineral component at the mine face. Since the slurry must first be conditioned prior to separation, these embodiments require the continual transport of large volumes of slurry as it is conditioned.
[0010] In Canadian Patent Application No. 2,453,697, the idea of a process line comprising a combination of mobile and relocatable equipment units at the face of an oil sand mine site is suggested. The '697 application proposes a process comprising a mobile excavator that advances along a mine face, a mobile comminutor that advances behind the excavator to crush the mined ore to a conveyable size, and a relocatable conveyor that extends along the mine face for receiving the crushed oil sand and conveying it to a relocatable slurry facility for preparing slurry for hydro-transport. The slurry facility may be connected directly to a fixed pipe for hydro-transport. The process line of the '697 application allows for relatively small components, such as the excavator and comminutor, to be mobile and follow the mine face as digging progresses. Less transportable equipment such as the slurry facility and hydro-transport pipe, are relocatable. That is, they are stationed in a fixed location for an extended period of time (months), but may be relocated once the excavator has removed all of the ore within near proximity to the relocatable conveyor.
[0011] The disclosure of the '697 application suffers from several limitations. First, the dwell time of the slurry facility is determined solely by the rate of excavation and the length of the first relocatable conveyor. Thus, to increase the dwell time in a particular location, either the rate of excavation must be slowed or the length of the conveyor must be increased. The Northern Alberta region has extremely harsh weather conditions and it has been found that extensive conveyors consume a considerable amount of energy, and are prone to break down resulting in work stoppage. For this reason, the length of the conveyor is preferably not overly long. However, it is also desirable that the slurry facility be relocated as seldom as possible necessitating a minimum length of conveyor in order to access a suitable volume of ore to supply the slurry facility. An additional limitation of the '697 application is that a practical relocatable slurry facility or relocatable desanding facility is not disclosed.
[0012] A further problem faced by the industry is the extensive use of water to extract the bitumen from the ore. While the sand portion of the mineral component may be practically removed from the slurry, the fine tailings, clay and other fine-sized material, is difficult to remove from the tailings and tends to remain in suspension. The solution to date has been to store the tailings in ponds for a sufficient period to allow the fines to settle out of the water. It has been determined, however, that it takes an extremely long period of time for the fines to settle out, resulting in ever increasing tailings ponds. Additionally, water becomes trapped in the interstitial spacing between particles so that even after the fines have settled a large amount of water is trapped in the settled material. Other than the excessive water requirements, tailings ponds create an environmental and logistical challenge as tailings must be continually disposed of in the continuously growing volume of tailings ponds which must be contained and maintained for years. There thus exists a need for a method of processing oil sands that obviates the need for extensive tailings ponds and provides for the recycling of water from the tails soon after deposition at a deposition site.
[0013] A further limitation of the prior art is that there is no practical solution provided for handling tailings. Rather, current deposition methods result in a separation of a course tails and a fine tails, maintaining the need for extensive tailings ponds to provide settlement of the fine tailings component. There thus exists a need for a method of processing oil sands that produces a whole dry tails comprising both the sand component and the fine tailings.
[0014] There thus exists a need to increase the efficiency of excavation and transport processes to reduce operating costs. There exists an additional need to increase the operating period for an excavator servicing a transportable slurry facility, without increasing the distance of ore transport from the excavator to the facility. There exists a further need for a process capable of removing the mineral component of the oil sands at a proximate location to the mine face without the creation of extensive tailings ponds.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In drawings which illustrate by way of example only a preferred embodiment of the invention,
[0016] FIG. 1 is an illustration of an embodiment of the process of the present invention.
[0017] FIG. 2 is a top view illustration of an embodiment of the process line of the present invention.
[0018] FIG. 3 is a top view illustration of an embodiment of the present invention.
[0019] FIG. 4 is a side view illustration of an embodiment of the present invention.
[0020] FIG. 5 is a side view illustration of an embodiment of the present invention.
[0021] FIG. 6 is a side view illustration of an embodiment of the present invention.
[0022] FIG. 7 is a side view illustration of an embodiment of the present invention.
[0023] FIG. 8 is a side view illustration of an embodiment of the present invention.
[0024] FIGS. 9 a - 9 c are top view illustrations of an embodiment of the present invention.
[0025] FIGS. 10 a - f are top view illustrations of an embodiment of the present invention.
[0026] FIG. 11 is a top view illustration of an embodiment of the present invention.
[0027] FIG. 12 is a process illustration of an embodiment of the present invention.
[0028] FIG. 13 is an isometric illustration of an embodiment of the present invention.
[0029] FIG. 14 is a side view illustration of an embodiment of the present invention.
[0030] FIG. 15 is a bottom view illustration of an embodiment of the present invention.
[0031] FIG. 16 is a side view illustration of an embodiment of the present invention.
[0032] FIG. 17 is a schematic view showing an embodiment of a modular, mobile extraction system according to an aspect of the present invention incorporating a plurality of mobile cyclone separation stages forming a mobile cyclone separation facility and a mobile froth concentrator vessel defining a mobile froth concentration facility.
[0033] FIGS. 18 a to 18 f are schematic plan views showing embodiments of the present invention.
[0034] FIGS. 19 a to 19 c are schematic plan views showing embodiments of the present invention.
[0035] FIGS. 20 a and 20 b are schematic plan views showing an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0036] In one aspect the invention provides a process line for mining an oil sands ore body, the process line comprising an excavator for mining oil sands ore; a comminutor for receiving mined ore from the excavator, comminuting the mined ore to conveyable size and transferring the comminuted ore to a mobile conveyor for transporting the comminuted ore; the mobile conveyor having a free end, a discharge end and at least one drive for advancing the conveyor through an operational arc generally about the discharge end; whereby the excavator mines a section of ore within operational reach along the length of the mobile conveyor and supplies the mined ore to the comminutor, and the comminutor supplies conveyable ore to the mobile conveyor, and whereby the mobile conveyor is periodically moved about the discharge end to locate another portion of the ore body within operational reach of the mobile conveyor until substantially all of the ore body within the operational arc has been mined.
[0037] In a further aspect the invention provides a mobile conveyor for transferring mined oil sands ore from a mine face, the conveyor comprising: two or more conveyor sections; each of the two or more sections having at least one drive for advancing the conveyor, and at least one alignment device for detecting misalignment between at least one adjacent section and controlling the drive responsive to a detection of misalignment to align adjacent sections.
[0038] In a further aspect the invention provides a method of mining oil sands ore with a mobile conveyor, the method comprising:
[0039] at a first conveyor position:
excavating and sizing ore at a mine face within operational reach of the first position; transferring the sized ore to the conveyor; conveying the sized ore along the conveyor; and discharging the sized ore; after excavating, sizing and transferring substantially all the ore within operational reach of the conveyor in the first conveyor position, advancing the conveyor generally about the discharge end to a second conveyor position; and, excavating, sizing and transferring substantially all the ore within operational reach of the conveyor at the second position.
[0045] In a further aspect the invention provides a method of mining oil sand ore with a mobile conveyor, the method comprising: excavating, sizing and transferring to the conveyor all ore within operational reach along the length of the conveyor; conveying the sized ore along the conveyor to a discharge end of the conveyor; advancing the conveyor generally about the discharge end to locate the conveyor within operational reach of a further section of oil sand ore; excavating, sizing and transferring to the conveyor all ore in the further section within operational reach along the length of the conveyor; continuing to advance the conveyor about the discharge end to locate the conveyor within operational reach of additional sections of oil sand ore and after each advancement excavating, sizing and transferring the respective additional section of oil sand ore, until substantially all ore within an operational arc sector generally about the discharge end has been excavated, sized and transferred to the conveyor.
[0046] In a further aspect the invention provides a method of extracting a body of oil sand ore for conveyance to a mobile slurry facility, the method comprising: locating the mobile slurry facility near a mine face of a body of oil sand ore; positioning a mobile conveyor within operational reach of a section of the ore body and locating a discharge end of the mobile conveyor to convey mined ore to the mobile slurry facility; extracting the section of the ore body and conveying it to the mobile slurry facility; advancing the mobile conveyor generally about the discharge end to locate the mobile conveyor within operational reach of a further section of the ore body; extracting the further section of the ore body and conveying it to the mobile slurry facility; continuing to advance the conveyor and convey additional sections of the ore body to the mobile slurry facility until the ore within an arc sector about the discharge end of the conveyor has been extracted.
[0047] In a further aspect the invention provides a method of increasing the effective length of a mobile conveyor for conveying a mined ore, the method comprising:
(a) Locating a mobile conveyor within operational reach of a section of ore; (b) Extracting the section of ore within operational reach of the conveyor and transferring the extracted ore to the conveyor; (c) Advancing the conveyor generally about the discharge end to locate the conveyor within operational reach of a further section of ore; (d) Repeating steps (b) and (c) until substantially all ore within operational reach of the conveyor has been extracted. and, (e) relocating the discharge end of the conveyor to a substantial center of the arc.
[0053] In a further aspect the invention provides a method for increasing the mineable volume of ore capable of being transported from the mine site to a discharge point using a mobile conveyor, the method comprising: locating the mobile conveyor near a mine face with a discharge end located in communication with the discharge point; excavating a section of ore within operational reach of the mobile conveyor along the length of the conveyor; repeatedly advancing the mobile conveyor through an operational arc generally about the discharge end to locate and extract additional sections of ore within operational reach along the length of the conveyor; and, relocating the mobile conveyor to locate the discharge end in communication with a new discharge point located near the perimeter of the operational arc.
[0054] In a further aspect the invention provides a process line for excavating and processing oil sands ore near a mine face, the process line comprising: a mobile excavator for excavating ore along the length of a mobile mining conveyor; a mobile comminutor for receiving and comminuting excavated ore and transferring comminuted ore to the mobile mining conveyor; the mobile mining conveyor conveying the comminuted ore to a transfer conveyor; the transfer conveyor conveying the comminuted ore to a mobile slurry facility; the mobile slurry facility converting the comminuted ore into a slurry and pumping and conditioning the slurry through a hydro-transport pipeline to a mobile extraction facility; the mobile extraction facility receiving the slurry and combining with a water stream to separate a bitumen stream and a tailings stream from the slurry; herein the bitumen stream is directed to a separation facility and the tailings stream is directed to a tailings treatment facility.
[0055] In a further aspect the invention provides a process line for excavating and processing oil sands ore near a mine face, the process line comprising: a mobile excavator for excavating ore along the length of a mobile mining conveyor; a mobile comminutor for receiving and comminuting the excavated ore and transferring the comminuted ore to the mobile mining conveyor; the mobile mining conveyor conveying the comminuted ore to a transfer conveyor; the transfer conveyor conveying the comminuted ore to a mobile slurry facility; at the mobile slurry facility combining the comminuted ore with process water to produce a slurry and pumping and conditioning the slurry through a hydro-transport pipeline to a mobile extraction facility as a slurry feed; at the mobile extraction facility receiving the slurry feed and directing the slurry feed and a water stream as inputs to a three stage countercurrent cyclone separator; the cyclone separator producing a bitumen rich stream and a tailings stream; the bitumen rich stream being directed to a froth concentration unit; the froth concentration unit separating the bitumen rich stream into a bitumen product stream, a recycled water stream and a fine tailings stream; the fine tailings stream being combined with the tailings stream to produce a tailings product stream; the tailings product stream being directed to a tailings treatment facility; the tailings treatment facility receiving the tailings product and combining the tailings product with an additive to produce a treated tailings stream; the treated tailings stream being directed to a tailings pond; the treated tailings stream being separated into a dry tails phase and a water phase; and, the water phase being collected at the tailings pond and recycled as industrial process water.
[0056] FIG. 1 is an illustration of the process overview of the present invention. The aim of the present invention is to provide a closed loop mining process that minimises the transport of the mineral component of the ore from the mine face and treats the tails to release the water component for reclamation as industrial process water. The process may be described as comprising the following main stages:
[0057] excavating the ore 10 ;
[0058] conveying the excavated ore to a slurry facility 12
[0059] slurrying the comminuted ore 14 ;
[0060] hydro-transporting the slurry to condition the slurry and transport it to an extraction facility 16 ;
[0061] extracting from the slurry an enriched bitumen froth feed and a tailings feed 18 ;
[0062] treating the tailings feed with an additive 20 ;
[0063] depositing the treated tailings feed at a deposition site 22 ; and,
[0064] recycling the reclaimed water as industrial process water 24 .
[0065] FIG. 2 depicts the process line of the present invention comprising a mobile excavator 200 that excavates ore from a mine face 101 and transfers the excavated ore to a mobile comminutor 500 . The mobile comminutor 500 comminutes the ore to transportable size for delivery to a mobile mining conveyor 580 . The mobile mining conveyor 580 delivers the crushed ore to a mobile slurry facility 800 where the crushed ore is converted into a slurry with the addition of hot process water and further comminuting and screening. Optionally process agents or conditioning aids may be added to the slurry at the mobile slurry facility 800 . The slurry is pumped through a hydro-transport pipeline 850 to a mobile extraction facility 900 where the bitumen is separated from the mineral component. The separated bitumen is diverted to a secondary extraction facility 1500 while the mineral component is directed for tailings treatment 1100 prior to being deposited at a tailings deposition site 1150 . Tailings treatment 1100 preferably comprises the addition of an additive to the tailings to assist in separation of the water component of the tailings from the sand and fines. The treated tailings are then deposited at tailings deposition site 1150 . After separation of the water from the solid component of the tailings, the water may be collected at the tailings deposition site and recycled as industrial process water, either back into the process, for instance to be used in the slurry and extraction stages, or else directed for other industrial process water uses.
[0066] The stages of the process will now be described in more detail.
[0067] Referring to FIG. 3 , a top view of the excavation portion of the present invention is shown. A mobile excavator 200 , for instance a shovel, removes ore from the ore body 100 at the mine face 101 . The mobile excavator 200 transfers the ore to a mobile comminutor 500 before it is transported to the mobile slurry facility 800 . The ore is deposited into the apron feed hopper 520 of the mobile comminutor 500 that feeds an apron feeder 530 to deliver the mined ore to primary comminuting rolls to comminute, or crush, the ore down to transportable size. The apron feed hopper 520 serves the dual purpose of receiving the excavated ore and acting as a “dry” surge or inventory of excavated ore by receiving buckets of excavated ore and delivering a steady stream of excavated ore to the primary comminuting rolls. The comminuted ore falls onto the discharge conveyor 550 for conveyance from the mobile comminutor 500 to a mobile mining conveyor hopper 570 for delivery to mobile mining conveyor 580 . The mobile mining conveyor 580 conveys the comminuted ore to a transfer conveyor that delivers the ore to the mobile slurry facility 800 .
[0068] Referring to FIG. 4 , a side view of the excavation portion of the present invention is shown. The mobile excavator 200 is within close proximity of an ore body 100 and within operational reach of a mine face 101 . The mobile excavator 200 excavates ore from the mine face 101 . Prior to transport, the excavated ore must be sized and screened for reject material such as metal. The mobile excavator 200 directs the excavated ore to the mobile comminutor 500 which comminutes and screens the ore. Generally, the mobile comminutor 500 preferably includes tracks 510 , an apron feeder hopper 520 , an apron feeder 530 , primary comminuting rolls 540 and a discharge conveyor 550 . Cable reels 575 transported by the mobile mining conveyor hopper 570 , supply power and communication cables to the excavator 200 , and mobile comminutor 500 .
[0069] FIG. 5 is an illustration of the preferred embodiment of a mobile comminutor 500 according to the present invention. The ore is initially deposited by the excavator 200 into the apron feeder hopper 520 which directs the ore onto an apron feeder 530 . The apron feeder 530 conveys the ore to the primary comminuting rolls 540 which comminutes the ore down to a conveyable size typically limiting ore pieces to a diameter of approximately less than about 350 mm. The apron feeder 530 and primary comminuting rolls 540 also preferably includes at least two level detectors. The feeder level detector 532 is directed down the apron feeder 530 to detect large lumps of ore travelling up the apron feeder 530 . When a large lump is detected, the feeder level detector 532 alerts the apron feeder 530 to slow down, to allow the material to be processed by the primary comminuting rolls 540 . Similarly, sizing level detector 534 is directed across the primary comminuting rolls 540 to detect a build-up of material at the primary comminuting rolls 540 . If the level of ore begins to build up above the primary comminuting rolls 540 , the comminuting level detector 534 alerts the apron feeder 530 to slow down the delivery of ore to allow time for the primary comminuting rolls 540 to process the built up ore. Preferably the speed of the apron feeder 530 is also controlled by a weight sensor located on the discharge conveyor 550 . By controlling the speed of the apron feeder 530 using the level detectors and weight sensor, a steady supply of transportable sized ore may be provided to the mobile mining conveyor 580 . Optionally, heaters 522 may be provided at the hoppers and elsewhere as required to minimize build-up of ore when operating under extreme cold conditions.
[0070] The mobile comminutor 500 preferably includes tracks 510 to permit relocation of the mobile comminutor as the excavator 200 works the ore body. FIGS. 19 a to 19 c illustrate an embodiment where the mobile comminutor 500 relocates each time the excavator 200 relocates to work a section of the ore body. As illustrated in FIGS. 19 a to 19 c , the excavator 200 excavates all ore within its operational reach at a particular location, and then relocates closer to the newly exposed mine face 101 . As the excavator 200 relocates, the comminutor 500 and mobile mining conveyor hopper 570 also relocate to pace the excavator 200 . In the embodiment of FIGS. 19 a to 19 c the mobile comminutor 500 takes multiple short relocation steps at the same time that the excavator is relocating.
[0071] FIGS. 20 a and 20 b illustrate an alternate embodiment in which the excavator 200 excavates all ore within its operational reach at a particular location, and then relocates closer to the newly exposed mine face 101 , but remaining within operational reach of the mobile comminutor 500 . In this fashion, the excavator takes multiple relocation steps excavating about the mobile comminutor 500 location until all ore within operational reach of the mobile comminutor 500 has been excavated. Once the ore has been excavated, both the mobile comminutor 500 relocates to a new location closer to the newly exposed mine face 101 . In the embodiment of FIGS. 20 a and 20 b , the mobile comminutor 500 takes less relocation steps to access all ore within operational reach of the mobile mining conveyor 580 . The excavator 200 may, however, take additional relocation steps or face some periods of down time while waiting for the mobile comminutor 500 to relocate closer to the newly exposed mine face 101 .
[0072] Optionally the mobile comminutor 500 includes supports 515 that are preferably lowered during operation while the excavator 200 is working a section of the ore body 100 to stabilise the mobile comminutor 500 . The supports 515 may preferably be raised to permit the mobile comminutor 500 to relocate when the excavator 200 moves to a new section of the ore body 100 . It will be appreciated that supports 515 may be replaced by additional tracks 510 , or dispensed with entirely, depending upon the weight distribution and stability of the mobile comminutor 500 .
[0073] The sized ore is directed to a discharge conveyor 550 for delivery to the mobile mining conveyor 580 . Ore that is too large, or too hard to be crushed in the primary comminuting rolls 540 , is directed to a reject door and discharged out the reject chute to the ground below the mobile comminutor 500 . Preferably the ore is also screened at the mobile comminutor 500 for metal contaminant, such as excavator teeth. As will be appreciated, other methods of screening the ore for metal and discarding metal are possible, such as screening the ore downstream after conveyance by the mobile mining conveyor 580 . Most preferably, however, the mobile comminutor 500 includes a metal detector 552 to examine the sized ore on the discharge conveyor 550 for metal contaminants. If metal is detected by metal detector 552 , the apron feeder 530 and discharge conveyor 550 may be temporarily halted and a reject chute in the mobile mining conveyor hopper 570 may be aligned under the discharge point of the discharge conveyor 550 . The discharge conveyor 550 then advances until the metal is discarded off the discharge conveyor 550 and into the reject chute. The discharge conveyor 550 is then temporarily halted again while the mobile mining conveyor hopper 570 is re-aligned to direct discharged ore to the mobile mining conveyor 580 .
[0074] Referring to FIG. 6 , the sized ore is first delivered to a mobile mining conveyor hopper 570 by the discharge conveyor 550 . The mobile mining conveyor hopper 570 preferably traverses along rails or tracks that run the length of the mobile mining conveyor 580 . As the excavator 200 advances along the mine face, the mobile comminutor 500 follows the progress of the excavator. The mobile mining conveyor hopper 570 traverses along the transfer conveyor 580 to receive the crushed ore from the discharge conveyor 550 and deliver it to the mobile mining conveyor 580 for conveyance. Preferably, the mobile mining conveyor hopper 570 conveniently includes cable reels 575 to spool out power and communication cables to the mobile comminutor 500 and excavator 200 as they traverse along the mine face 101 . In this manner, the power generation or transmission connection may be conveniently located at the discharge end 590 , of the mobile mining conveyor 580 , minimizing the need to move such equipment. The mobile mining conveyor 580 also preferably comprises crawler tracks 600 distributed along the length of the conveyor which enables the mobile mining conveyor 580 to advance laterally or to advance about and end of the mobile mining conveyor 580 . Optionally, the mobile mining conveyor 580 may be accompanied by a fluid trailer 585 that supplies water or glycol to be sprayed on the transfer conveyor 580 belt to prevent material from sticking to the belt in extreme weather conditions.
[0075] In a preferred embodiment the mobile mining conveyor 580 is comprised of multiple conveyor sections that are connected together to create a chain of conveyor sections that collectively comprise the mobile mining conveyor 580 . A continuous belt is supported by the sections to convey ore to the discharge end of the mobile mining conveyor 580 . Preferably, each section includes at least one crawler track 600 to reposition that section. More preferably the crawler tracks 600 are provided with independent height adjustable supports connecting the crawler tracks 600 to the mobile mining conveyor 580 . In a preferred embodiment the sections are joined by pivot joints and an alignment gauge 585 , such as string pots, is used to determine whether a section is inline with its adjacent sections. If the section is not inline, the section's crawler track 600 is repositioned until the section is inline and horizontal. In this way, the mobile mining conveyor 580 may be advanced generally about the discharge end 590 by manually advancing the free end to a desired location. With the advancement of the free end crawler track, the adjacent section will no longer be inline with the end section. Upon detecting mislevel or misalignment, the adjacent section crawler track is also repositioned to maintain level alignment with the end section. Similarly, the next section in the chain detects a misalignment with the adjacent section and its crawler track is repositioned to maintain level alignment. In this way the mobile mining conveyor 580 may be advanced about the discharge end 590 by manually advancing the free end crawler until it is in operational proximity to the current mine face 101 . Alternatively the crawler tracks 600 may be controlled by a central motion controller to co-ordinate the advancement of all crawler tracks 600 .
[0076] One advantage of employing a mobile mining conveyor 580 , over a relocatable conveyor, is that material that spills over the sides of the mobile conveyor does not significantly accumulate in a particular location. Depending upon the duration of operation the amount of spilled material that may accumulate around a relocatable conveyor may be considerable. By mining with a mobile mining conveyor 580 , the process avoids the need to clear spilled material prior to relocating the conveyor.
[0077] Referring to FIGS. 7 and 8 , at the discharge end 590 of the mobile mining conveyor 580 , the sized ore is deposited into a transfer conveyor hopper 610 that feeds the sized ore onto a transfer conveyor 620 that transports the material to the feed chute of a mobile slurry facility 800 .
[0078] The mobile mining conveyor 580 conveys sized ore along its length to the discharge end 590 . The discharge end 590 is in communication with a discharge point such that as sized ore is discharged off the discharge end 590 , it continues in a projectile motion to the discharge point a short distance from the discharge end 590 . In operation the mobile mining conveyor 580 is positioned such that the discharge point of the mobile mining conveyor is aligned with a target, in this case approximately the center of the transfer conveyor hopper 610 . Preferably a location sensor is included to assist in locating the discharge point of the mobile mining conveyor 580 central to the transfer conveyor hopper 610 , and maintaining its alignment with respect to transfer conveyor hopper 610 , while advancing the mobile mining conveyor 580 about the discharge end 590 .
[0079] According to a preferred embodiment of the present invention, the mobile mining conveyor 580 consists of multiple independent sections. One of the advantages of the preferred embodiment is that each section may be individually powered and operated depending upon the location of the mobile mining conveyor hopper 570 . Similarly, since each section is independently mobile, each section may be replaced as necessary if it breaks down while in service. Alternatively, a section may be removed from the mobile mining conveyor 580 and operation may continue, albeit with a mining conveyor of shorter length. Preferably the conveyor belt is a continuous belt as known in the art. Conveyor sections may be added or removed by adding or removing sections of the belt to accommodate the change in the length of the conveyor.
[0080] In a preferred embodiment the location sensor is optical sensor 595 located at the discharge end 590 that monitors the location of a positioning ring 605 located around the transfer conveyor hopper 610 . As the mobile mining conveyor 580 is advanced about the transfer conveyor hopper 610 , the optical sensor 595 monitors the location of the positioning ring 605 and provides feedback to control the advancement of the tracks 600 on the discharge conveyor section 597 so as to maintain the discharge point in the transfer conveyor hopper 610 . Since the discharge end 590 is located with reference to the transfer conveyor hopper 610 , the geometry of the transfer conveyor hopper 610 may effect the path through which the discharge end 590 , and hence the mobile mining conveyor 580 , may travel. For instance, the transfer conveyor hopper 610 may be circular in which case the discharge end 590 will travel in a generally circular fashion. Alternatively, the transfer conveyor hopper 610 may be elongate in which case the discharge end 590 may travel in a generally arcuate fashion.
[0081] As described above, the mobile mining conveyor 580 conveys the sized ore off the discharge end 590 to a discharge point aligned with the transfer conveyor hopper 610 of a transfer conveyor 620 for delivery to the mobile slurry facility 800 where it is converted into a slurry and pumped into pipe-line 850 for transport to a de-sanding facility en route to a bitumen upgrader facility. Since the mobile mining conveyor 580 advances about the transfer conveyor hopper 610 , the transfer conveyor 620 may remain stationary throughout the execution of an operational arc. Preferably the transfer conveyor 620 is provided with a platform 630 on its underside for engaging a crawler when the transfer conveyor 620 is to be repositioned. In this embodiment it is unnecessary to include a motive drive on the transfer conveyor 620 since it remains stationary for extended periods of time.
[0082] Referring to FIGS. 9 a - 9 b , preparation of an ore body according to a preferred embodiment of the present invention is presented. Preferably, the ore body is prepared by initially excavating a “pocket” 55 into the mine face 101 with the excavator 200 and mobile comminutor 500 to remove all of the ore within operational reach of the excavator 200 and mobile comminutor 500 while a discharge point off the discharge conveyor 550 is located outside the pocket 55 being excavated. The purpose of excavating the pocket 55 is to permit location of the mobile slurry facility 800 as close as possible to the mine face to facilitate removing the greatest possible volume of ore while the mobile slurry facility 800 remains in a single location. While it is possible to operate the excavator 200 and mobile comminutor 500 further into the ore body beyond the operational reach of the excavator 200 and mobile comminutor 500 , limiting excavation to their operational reach with the discharge point being located outside the pocket 55 minimises the need to employ additional equipment to transport the ore clear of the pocket 55 .
[0083] As illustrated in FIG. 9 c , after excavation of the initial pocket, the mobile slurry facility 800 and transfer conveyor 620 may be positioned such that the transfer conveyor hopper 610 is located in the pocket, thus locating the mobile slurry facility 800 at an optimal location for removing a maximum volume of ore before having to move the mobile slurry facility 800 . Optionally, as illustrated in FIG. 9 c , the excavator 200 and mobile comminutor 500 may continue to work the ore body to enlarge the pocket 55 without the mobile mining conveyor 580 by locating a discharge point off the discharge conveyor 550 in the apron feed hopper 610 . An additional volume of the ore body is within operational reach of the excavator 200 and mobile comminutor 500 when the discharge point is located in the transfer conveyor hopper 610 within the pocket 55 . The advantage of excavating an enlarged pocket by delivering the ore directly from the mobile comminutor 500 to the transfer conveyor hopper 610 is that it consumes less energy and results in less wear and tear on equipment. Optionally, the ore excavated during the initial pocket excavation, illustrated in FIGS. 9 a - 9 b , may be fed into the mobile slurry facility 800 at this time by depositing the ore in the transfer conveyor hopper 610 . Alternatively, the initially excavated ore may be retained as a dry surge to feed to the mobile slurry facility during excavation down time such as excavator shovel repairs or conveyor maintenance.
[0084] Referring to FIGS. 10 a - 10 e a top view schematic of the process of the present invention is presented. FIG. 10 a illustrates a close-up top view of a mining cell according to an embodiment of the present invention with the ore body 100 and the mobile mining conveyor 580 in an initial position. The excavator 200 removes ore from a mine face 101 and delivers it to a mobile comminutor 500 by depositing it in the apron feed hopper 520 to be directed to an apron feeder 530 . The apron feeder 530 carries the ore to primary comminuting rolls 540 , not shown in this view, for crushing before the ore is directed to the discharge conveyor 550 to be transferred to the mobile mining conveyor hopper 570 to direct the ore to the mobile mining conveyor 580 for delivery off the discharge end 590 of the mobile mining conveyor 580 to a discharge point. Preferably, the mobile mining conveyor 580 is oriented to position the discharge point in a transfer conveyor hopper 610 . Most preferably the mobile mining conveyor 580 positions the discharge point at or near the center of the transfer conveyor hopper 610 . The transfer conveyor hopper 610 supplies the conveyable ore to a transfer conveyor 620 that delivers the ore to a mobile slurry facility 800 . The mobile slurry facility 800 adds HPW to convert the ore into a slurry that is pumped into a pipe-line 850 for hydro-transport.
[0085] FIG. 10 b illustrates the mining cell in a top view with the ore body 100 to be excavated and the excavator 200 , mobile comminutor 500 and mobile mining conveyor hopper 570 starting at an end of the mobile mining conveyor 580 and removing ore within operational reach along the length of the mobile mining conveyor 580 .
[0086] FIG. 10 c illustrates the mining cell in a top view after all the ore within operational reach of the mobile mining conveyor 580 in the first position has been excavated and the conveyor has been advanced about the discharge end 590 to position a further section of ore within operational reach of the mobile mining conveyor 580 while locating the discharge point in the transfer conveyor hopper 610 . As illustrated, once the mobile mining conveyor 580 has been advanced, the excavator 200 , mobile comminutor 500 and mobile mining conveyor hopper 570 move along the mobile conveyor 580 and excavate the ore within operational reach of the mobile mining conveyor 580 . After all the ore within operational reach of the mobile mining conveyor 580 has been excavated, the mobile mining conveyor 580 is again advanced about the discharge end.
[0087] FIG. 10 d illustrates the mining cell in a top view with the ore body 100 and the mobile mining conveyor 80 having been advanced to a further position and the excavator 200 , mobile comminutor 500 and mobile mining conveyor hopper 570 having completed excavating all the ore within operational reach of the mobile mining conveyor 580 in the further position.
[0088] FIG. 10 d illustrates the mining cell in a top view with the ore body 100 and the mobile mining conveyor 80 having been advanced to a further position and the excavator 200 , mobile comminutor 500 and mobile mining conveyor hopper 570 having completed excavating all the ore within operational reach of the mobile mining conveyor 580 in the further position.
[0089] FIG. 10 e illustrates the mining cell in a top view with the ore body 100 and mobile mining conveyor 80 having been advanced through an operational arc about the discharge end and the excavator 200 and mobile comminutor 500 having excavated, comminuted and transferred to the mobile mining conveyor hopper 570 an operational arc sector of ore.
[0090] FIG. 10 f illustrates the mining cell in a top view with the ore body 100 after the excavator 200 and mobile comminutor 500 have prepared an initial pocket at the perimeter of the excavated arc sector. The mobile slurry facility 800 has been moved from its prior location to be in close proximity to the mine face 101 with the transfer conveyor 620 located in the pocket. The excavator 200 and mobile comminutor 500 are initiating excavation of an enlarged pocket about the transfer conveyor hopper 610 . The mobile mining conveyor 580 has been positioned in close proximity to the mobile slurry facility 800 and transfer conveyor 620 to begin operation after the excavator 200 and mobile comminutor 500 have completed the enlarged pocket.
[0091] FIG. 11 illustrates the mining cell in a top view with the ore body 100 after the mobile mining conveyor 580 has been advanced through an operational arc sector about a mobile slurry facility 800 . In comparison to the embodiment illustrated, a conventional fixed conveyor 575 of similar length is illustrated with the operational reach of the conventional fixed conveyor 575 illustrated with cross-hatching 585 . As will be appreciated the effective length of the mobile mining conveyor 580 is greater than that of a conventional fixed conveyor 575 since a greater volume of ore may be excavated before relocating the mobile slurry facility 800 with a mobile mining conveyor 580 according to the present invention.
[0092] As described above, the discharge end 590 of the mobile mining conveyor hopper 580 delivers conveyable ore to the transfer conveyor hopper 610 of the transfer conveyor 620 . The transfer conveyor 620 supplies the conveyable ore to the mobile slurry facility 800 . Since the mobile slurry facility 800 preferably utilises gravity to assist in slurrying the ore, the transfer conveyor 620 serves to elevate the conveyable ore to the height of the mobile slurry facility 800 ore input chute. The use of a transfer conveyor 620 to offset the mobile slurry facility 800 from the discharge end 590 also provides the opportunity to increase the operational arc of the mobile mining conveyor hopper 580 . Furthermore, a single mobile slurry facility 800 may be used to process ore from multiple mobile mining conveyors 580 . In such an embodiment, the transfer conveyor 620 may be longer than the minimum length required for supplying conveyable ore to a mobile slurry facility 800 fed by a single mobile mining conveyor 580 .
[0093] FIG. 18 a is an illustration of a mobile mining conveyor 580 combined with an extended transfer conveyor 623 feeding the transfer conveyor 620 . The embodiment of FIG. 18 a allows a mobile mining conveyor 580 to access a greater volume of ore before the mobile slurry facility 800 requires relocation. An additional feature of traversing the mobile mining conveyor 580 along the extended transfer conveyor 623 before rotating the mobile mining conveyor 580 about the distal end 623 b of the extended transfer conveyor 623 , is that it provides access to a section of ore body having straight sides. Among other uses, such an arrangement may be useful to access a volume of ore from a given mobile slurry facility 800 location when the ore body is of a relatively narrow width. The extended transfer conveyor 623 allows a larger volume of ore to be accessed than would otherwise be the case for the mobile mining conveyor 580 of a given length.
[0094] FIG. 18 b illustrates an embodiment where a single mobile slurry facility 800 may be used to process ore from multiple mobile mining conveyors 580 a , 580 b . In the embodiment illustrated, two mobile mining conveyors 580 a , 580 b access adjacent volumes of ore. Each of the discharge ends 590 a , 590 b pivot about a separate discharge point for transferring ore to conveyors 625 a , 625 b that convey the mined ore to their discharge ends 592 a , 592 b to feed transfer conveyor 620 . The discharge points may be fixed at a point along the conveyors 625 a , 625 b , as illustrated in FIG. 18 b , or alternatively as illustrated in FIG. 18 f , mobile conveyor hoppers may be used to allow the discharge points to traverse along the conveyors 625 a , 625 b . After the mobile mining conveyors 580 a , 580 b have completed an arc sector as suggested in FIG. 18 b , one of the mobile mining conveyors 580 a , 580 b may be positioned to pivot about a discharge end 592 c located at the transfer conveyor 620 to remove a further section of ore between the arc sectors illustrated within reach of the mobile mining conveyors 580 a , 580 b . The embodiment of FIG. 18 b allows for a large volume of ore to be processed with a single mobile slurry facility 800 at a location, increasing the time between moves for a given length of mobile mining conveyors 580 a , 580 b . The embodiment may be implemented in a variety of methods, including operating both mobile mining conveyors 580 a , 580 b simultaneously, to feed twice as much ore to the mobile slurry facility 800 , or alternately operating each conveyor to ensure a steady feed of ore, for instance when one conveyor is inoperative, such as when equipment is moving or a shift change occurs.
[0095] FIGS. 18 c and 18 d are plan view schematics, illustrating an embodiment where multiple mobile mining conveyors 580 , 581 are deployed in series. The conveyors 580 , 581 may be of similar length, or may comprise different lengths as is convenient for excavating a particular ore body 100 . The excavator 200 and mobile comminutor 500 work the ore body 100 feeding mobile mining conveyor hopper 571 . The use of multiple mobile mining conveyors 580 , 581 allows for efficient mining of an ore body, including avoiding low yield volumes 105 (shown in plan views as an area). As illustrated in FIG. 18 c , the mobile mining conveyor 580 may be deployed as a face conveyor to allow mobile mining conveyor 581 to pivot about the mobile mining conveyor hopper 570 to access ore around the low yield volume 105 . FIG. 18 d illustrates an embodiment where the mobile mining conveyor 580 is pivoting about the transfer conveyor 620 , and the mobile mining conveyor 581 is pivoting about the mobile mining conveyor hopper 570 . In an embodiment, mobile mining conveyor 581 may be advanced through all of the ore within operational reach of the mobile mining conveyor hopper 570 as it traverses along the mobile mining conveyor 580 which is held in a fixed position for the duration of the advancement. Alternatively, the mobile mining conveyors may both be advanced by pivoting about the transfer conveyor 620 providing an effective mobile conveyor length a length equivalent to the combined lengths the mobile mining conveyors 580 , 581 .
[0096] FIG. 18 e illustrates an embodiment where multiple mobile mining conveyors 580 , 581 are deployed to excavate ore along mine wall limit 102 . As illustrated, the conveyors 580 , 581 may be of differing lengths as required to efficiently mine the wall limit 102 .
[0097] FIG. 18 f illustrates an embodiment where multiple conveyors are working an ore body 100 around low yield sections 105 . In the embodiment illustrated, the mobile mining conveyors 580 a and 580 b are of differing length to better work between low yield sections 105 . Mobile conveyor hoppers 570 traverse along conveyors 625 a , 625 b to allow access to minable ore in the ore body 100 and avoid the low yield sections 105 .
[0098] A mobile slurry facility 800 converts the conveyable ore delivered by the transfer conveyor 620 into a slurry for hydro-transport. In a preferred embodiment of the mobile slurry facility 800 the conveyable ore is first discharged from the transfer conveyor 620 into the roller screen feed chute 720 . The roller screen feed chute 720 feeds the roller screen 740 to crush the ore to a convenient size for slurrying (typically less than 65 mm in diameter) and allow the crushed and sized ore to fall through the screen. Oversize material that does not fall through the roller screen 740 passes to an oversize comminutor 760 that crushes the lumps of oversize down to acceptable size. Hot Process Water (HPW) is typically introduced at the roller screen feed chute 720 and additional HPW is added directly over the roller screen 740 and oversize comminutor 760 . The additional HPW assists in processing the ore, preventing ore buildup and defining the slurry density. The majority of the wet sized ore passes directly through the roller screen 740 for conversion to slurry in the slurry pump box 780 . The remaining oversize is wetted and crushed by the oversize comminutor 760 before falling into the slurry pump box 780 for conversion to slurry. While it is possible to provide for an overflow chute to discard oversize, it is preferable to size the roller screen 740 and oversize comminutor such that they are capable of processing all of the ore supplied by the transfer conveyor 620 .
[0099] Typically, HPW will be proportionately distributed approximately 70% at the roller screen feed chute 720 , 20% at the roller screen 740 and 10% at the oversize comminutor 760 . Where the invention includes a metal detector and reject ore discharge mechanism at the mobile comminutor 500 , all of the ore received by the mobile slurry facility 800 may be processed using the roller screen 740 and oversize comminutor 760 . While it is possible to detect metal in the ore at the roller screen 740 , it is preferable to discard reject material as soon as possible in the process. Furthermore, it is preferable to discard reject material prior to processing by the primary comminuting rolls 540 . One advantage of the combination of the mobile comminutor 500 and mobile slurry facility 800 of the present invention is that reject material is discarded near the location of excavation. As the excavator 200 works an ore body, detected reject material will be discarded near the location of its excavation. Not only does this avoid transporting reject material along the mobile mining conveyor 580 where it can damage equipment but it eliminates the need for reject material handling equipment at the mobile slurry facility 800 where it would be much more difficult to incorporate such equipment.
[0100] The sized ore and HPW falls into the slurry pump box 780 that is sized for a slurry retention time of approximately one minute. The slurry pump box 780 supplies the hydro-transport pump 820 with slurry. A one minute retention time is the preferred minimum to provide a wet surge capability to continuously supply slurry to the pump. When the level of slurry falls below a low level, Cold Process Water (CPW) may be added to maintain the level in the slurry pump box and ensure the hydro-transport pump 820 does not cavitate. As required, HPW may be added along with CPW to maintain a working temperature under cold conditions.
[0101] Emergency ponds are preferably located near the mobile slurry facility 800 to allow dumping of slurry from the mobile slurry facility 800 or the pipeline 850 under emergency conditions. The size of the emergency ponds is preferably large enough to accommodate the directed drainage of the contained volume of any one of the following: a drainable section of hydro-transport pipeline (24″), a drainable section of HPW pipeline (24″), a drainable section of CPW pipeline (20″), or the volume of the slurry pump box 780 . The size of the drainable sections of the pipelines are site specific due to logistical and geographical features. The emergency pond is preferably serviced by a submersible pump which is able to return the pond fluids back to the process through the slurry pump box at the end of the emergency.
[0102] The slurry is pumped through the hydro-transport pipeline 850 to an extraction facility. As mentioned above, in addition to transporting the slurry, the hydro-transport process serves the secondary purpose of conditioning the slurry. The length of hydro-transport required to condition the slurry depends on several factors including the grade of ore, temperature of the ore, temperature of the process water and the size of ore being delivered to the slurry pump box. Typically, to be fully conditioned the slurry requires at minimal distance of one kilometre of hydro-transport distance.
[0103] Preferably the extraction facility is a mobile extraction facility 900 that receives as inputs the conditioned slurry as an ore slurry feed 1200 and process water 1205 , and produces as outputs an enriched bitumen stream 1400 and a tailings stream 1450 . In a preferred embodiment, the mobile extraction facility 900 comprises separate portable modules that may be transported to a location separately and then connected together in series to provide a single extraction facility. Preferably the mobile extraction facility 900 comprises a primary separation facility connected to a froth concentration facility. More preferably, the primary separation facility comprises two or more separate separation cyclone modules that are combinable in situ to comprise the primary separation facility. Most preferably, the primary separation facility comprises three separate separation cyclone modules connected in series in a countercurrent configuration. The use of separate modules allows for ease of portability and allows the process to be flexible to tailor the extraction facility to the ore body being excavated. For instance, a high grade ore body that contains very little fine solids/mineral component may not require the rigor of a three cyclone circuit, and in such a case the extraction facility may comprise only one or two of the modules. Generally, to accommodate all ore types, a three cyclone system is preferred. The modules preferably comprise transportable platforms, such as skids, that may be transported by crawlers or other motive modules. Alternatively, the modules may be provided with driven tracks.
[0104] In an alternate embodiment, the mobile extraction facility 900 comprises a single facility, containing all separation vessels and primary froth concentration equipment.
[0105] Use of a three stage cyclonic system is further advantageous in a mobile extraction system for several reasons. First, the size of each individual cyclone stage may be reduced since a three stage counter—current process results in a separation efficiency either equivalent to, or better than, current extraction methods. Second, each of the three cyclones may be transported separately, greatly improving the ease of relocating the extraction facility. Third, the use of a three stage countercurrent cyclonic system allows a mobile extraction facility to operate with a variety of ore grades. Fourth, as mentioned above, the number of stages may be tailored to match the separation efficiency with the grade of ore being processed.
[0106] As described above, the slurry that is fed to mobile extraction facility 900 is generally formed using HPW. In conventional bitumen extraction equipment such as primary separation vessels (PSV), where bubble attachment and flotation are used for bitumen extraction, temperature can affect the efficiency of the extraction process. In the preferred extraction embodiments described above, the extraction process is not as temperature sensitive since the cyclone equipment provides solid/liquid separation based on rotational effects and gravity. Extraction efficiency tends to be maintained even as temperature drops making the cyclone extraction process more amendable to lower temperature extraction. This has energy saving implications at the mobile extraction facility 900 where water feed 1305 or recycled water stream 1370 do not have to be heated to the same extent as would otherwise be necessary to maintain a higher process temperature.
[0107] Preferably each of the cyclone separation modules are self-contained and include a cyclone, as well as associated connections, pump boxes, and pumps. This way, if one unit has a mechanical failure, the extraction facility may be brought back online by simply replacing the faulty cyclone separation unit. Preferably the cyclone separation modules are connected in series in a countercurrent configuration in which the water stream and slurry stream enter at opposite ends of the three cyclone combination. Thus, for example, water entering the process (either make-up, recycled, or both) is first contacted with a bitumen-lean feed at the last cyclone separation unit in the series. The cyclonic separation units are preferably vertical cyclones, which have a reduced footprint. Suitable cyclonic separation vessels include those manufactured by Krebs Engineers (www.krebs.com) under the trade-mark gMAX.
[0108] This modular arrangement of the extraction system provides for both mobility of the system and flexibility in efficiently handling of different volumes of ore slurry. For example, as illustrated in FIG. 17 , a preferred setup according to an aspect of the invention in which each cyclone separation stage 106 , 108 and 110 is mounted on its own independent skid 160 to form a mobile module. Positioned between each cyclone separation stage skid 160 is a separate pump skid 162 which provides appropriate pumping power and lines to move the froth streams and solid tailings streams between the cyclone separation stages. It is also possible that any pumping equipment or other ancillary equipment can be accommodated on skid 160 with the cyclone separation stage. In the illustrated arrangement of FIG. 17 , groups of three mobile modules are combinable together to form cyclone separation facilities 102 , 102 ′, 102 ″ to 102 n as needed. Also associated with each cyclone separation facility is a mobile froth concentration facility 130 mobile modules comprising skids or other movable platforms with appropriate cyclone stage or froth concentration equipment on board may be assembled as needed to create additional mobile extraction systems 200 ′, 200 ″ to 200 n to deal with increasing ore slurry flows provided by hydro-transport line 850 . Ore slurry from the transport line 850 is fed to a manifold 103 which distributes the slurry to a series of master control valves 165 . Control valves 165 control the flow of ore slurry to each mobile extraction system 200 to 200 n . This arrangement also permits extraction systems to be readily taken off-line for maintenance by switching flow temporarily to other systems.
[0109] According to a preferred embodiment, the cyclone separation units 1210 , 1220 , 1230 are connected as illustrated in FIG. 12 . The slurry is delivered by the hydro-transport pipeline 850 as an ore slurry feed 1200 to the first cyclone separation unit 1210 . The first cyclone 1210 separates the ore slurry feed 1200 into a first bitumen froth stream 1300 and first tailings stream 1310 . The first tailings stream 1310 is pumped to a feed stream of a second cyclone 1220 . The second cyclone 1220 produces a second bitumen froth stream 1320 and a second tailings stream 1330 . The second bitumen froth stream 1320 is combined with the ore slurry feed 1200 as the feed stream of the first cyclone 1210 . The second tailings stream 1330 is combined with a water feed 1305 as the feed stream of a third cyclone 1230 . The third cyclone 1230 produces a third bitumen froth stream 1340 and a third tailings stream 1350 . The third bitumen froth stream 1340 is combined with the first tailings stream 1310 as the feed stream of the second cyclone 1220 . The third tailings stream 1350 from the third cyclone 1230 forms a tailings stream 1400 that is pumped to a tailings treatment facility 1100 .
[0110] Optionally a “scalping” unit 1205 , such as a pump box or the like, may be included on the ore slurry feed 1200 to remove any froth formed in the slurry feed 1200 during the hydro-transport process and divert the bitumen froth directly to be combined with the first bitumen froth stream 1300 . Removal of the bitumen rich froth at the scalping unit 1205 assists in further increasing the recovery efficiency of the primary separation facility. Preferably, as indicated, the scalping unit 1205 is located upstream of the infeed of the second bitumen froth stream 1320 .
[0111] The first bitumen froth stream 1300 is directed to a froth concentration facility to reduce the water content, remove remaining fines, and produce an enriched bitumen product stream 1400 . Preferably, the froth concentration facility is located proximate to the primary separation facility. Most preferably, the froth concentration facility comprises a separate portable unit that may be combined with the primary separation facility units to comprise the mobile extraction facility 900 . Typically the froth concentration facility comprises at least a froth concentration vessel 1240 , such as a flotation column, a horizontal decanter, an inclined plate separator, or other similar device or system known to be effective at concentrating bitumen froth. In addition to the first bitumen froth feed, an air feed 1355 or chemical additive stream may also be introduced into the froth concentration vessel 1240 . Optionally the froth concentration facility may comprise a combination of effective devices. In a preferred embodiment, as illustrated in FIG. 12 , the froth concentration vessel 1240 comprises a flotation column. In a further preferred embodiment for a mobile extraction facility a horizontal decanter is used to separate an enriched bitumen stream from the first bitumen froth stream. The selection of a series of countercurrent cyclone separators results in a compact separation facility that remains able to remove the majority of the mineral component from the ore slurry feed 1200 . The low solids content of the first bitumen froth stream permits the use of a horizontal decantor as the froth concentration vessel with a low risk of plugging due to sedimentation. Use of a horizontal decantor is desirable due to its small footprint, thus allowing for the potential of the vessel being made movable, and still result in a robust extraction facility that has a low propensity of being fouled with silt or other mineral component.
[0112] Within the froth concentration vessel 1240 , the froth is concentrated resulting in an enriched bitumen froth product stream 1400 , that may optionally be transported to a secondary separation facility (not shown) to increase the hydrocarbon concentration in the froth before being pumped to an upgrader facility. Typically, the secondary separation facility will be a larger, more permanent facility. One advantage of the process of the present invention is that an enriched bitumen froth stream 1400 is produced relatively close to the excavation site, greatly reducing the current requirement to transport large volumes of water and mineral component to the permanent separation facility.
[0113] Froth concentration vessel 1240 also produces a fine tailings stream 1360 that comprises water and fine solids contained in the first bitumen froth stream 1300 . In one embodiment, any known chemical additives may also be used in the froth concentration facility to enhance the separation of fines from the water.
[0114] Preferably the fine tailings stream 1360 is diverted to a water recovery unit 1250 , which separates the fine tailings stream 1360 into a recycled water stream 1370 and a fine tailings stream 1380 . In a preferred embodiment, the water recovery unit 1250 is a hydrocyclone to separate small sized particulate since the majority of the mineral component is removed by the primary separation facility. The fine tailings stream 1380 is preferably combined with the third tailings stream 1350 to produce a tailings stream 1450 from the mobile extraction facility 900 . The recycled water stream 1370 is preferably combined with the water feed 1305 for input to the third cyclone. As necessary, the recycled water stream 1370 may also be combined with the third tailings stream 1350 , fine tailings stream 1380 or tailings stream 1450 as necessary to control the water content of the streams. Preferably density meters (not shown) monitor the streams to determine whether, and how much, recycled water 1370 should be added. The addition of water to the third tailings stream 1350 and tailings stream 1450 may be necessary to maintain a pumpable stream, as the primary separation facility removes most of the water from the third tailings stream 1350 and fine tailings stream 1380 . The water recovery unit 1250 provides significant efficiencies in that the process water used in the mobile extraction facility 900 is preferably heated. The recycled water stream 1370 is typically warm or hot, so that reintroducing the recycled water stream 1370 reduces the heat lost in the extraction process.
[0115] An advantage of this preferred embodiment of the present invention is that water may be recycled in the extraction process, and the mobile extraction facility 900 produces a single tailings stream 1450 .
[0116] In a further optional embodiment, the ore slurry feed 1200 may be provided with any number of known additives such as frothing agents and the like prior to being fed to the primary separation facility to prepare the ore slurry feed 1200 for extraction. An example of such additives would be caustic soda, geosol, or other additives as described in U.S. Pat. No. 5,316,664.
[0117] As mentioned above, the tailings stream 1450 is pumped to a tailings treatment facility 1100 . The tailings treatment facility 1100 may be located at the mobile extraction facility 900 , or some distance from the mobile extraction facility 900 depending upon the availability of a tailings deposition site 1150 . As will be appreciated, the location of the tailings deposition site 1150 is preferably close to the mobile extraction facility 900 to minimize the distance the tailings stream 1450 must be transported. However, the tailings treatment facility 1100 may be located distant from the mobile extraction facility 900 if it is necessary to locate the tailings deposition site 1150 at a distant location.
[0118] While the tailings treatment facility 1100 may comprise a known method or process of handling tailings, preferably tailings treatment facility 1100 comprises the addition of a rheology modifier or other such additive to the tailings stream 1450 prior to deposition at the tailings deposition site. An example of a suitable additive is described in PCT publication WO/2004/969819 to Ciba Specialty Chemicals Water Treatment Limited.
[0119] In a further preferred embodiment, the third tailings stream 1350 and fine tailings stream 1380 are mixed to ensure a homogenous distribution of coarse and fine particulate in the tailings stream 1450 . A preferred additive is a rheology modifier additive such as a water soluble polymer that may be added and mixed with the tailings stream 1450 to produce a treated tailings stream. The additive may be mixed into the tailings stream 1450 either during a pumping stage, or subsequently added in liquid form near the tailings deposition site. Preferably the treated tailings are deposited at the tailings deposition site and allowed to stand and rigidify thereby forming a stack of rigidified material. The addition of the additive results in a whole dry tails that rigidities relatively quickly to produce a relatively homogenous tailings deposition. After application of the additive, the water separates from the mineral component free from the fines. Unlike conventional tailings ponds, after addition of the additive the treated tailings produced according to the present invention releases water that is sufficiently clear to be recycled as industrial process water almost immediately after tailings deposition. Furthermore, the recycled industrial process water is often still warm, reducing the energy required to be added to produce hot process water. The industrial process water may be recycled back into the mobile extraction facility 900 , the mobile slurry facility 800 or other industrial processes as required. Furthermore, after separation of the water, the mineral component is comprised of both sand and fines, and is thus more stable than typical tailings produced by known processes. This provides the unique opportunity to reclaim the solid tailings relatively soon after excavation.
[0120] A suitable mobile slurry facility may comprise the slurry apparatus 10 illustrated in FIGS. 13 to 16 and further described in applicant's co-pending application METHOD AND APPARATUS FOR CREATING A SLURRY, filed Nov. 9, 2006 and claiming priority from CA2,526,336.
[0121] As shown in FIG. 13 , the slurry apparatus 10 provides a frame 20 having a base 22 . The frame 20 may optionally also be provided with sides 24 . The frame 20 is preferably formed from steel girders or I-beams having the required load-bearing capacity, welded, bolted, or otherwise suitably affixed together. The frame supports a slurry box 30 , which may be a conventional slurry box constructed to support the desired slurry load. The slurry box 30 essentially acts as a wet surge, maintaining the required constant supply of slurry to the slurry pump 39 . The slurry box 30 provides a slurry outlet 38 which feeds the slurry pump 39 , and the slurry pump 39 in turn provides a slurry outlet 41 to which a hydrotransport conduit (not shown) is detachably coupled by suitable means, for example a bolted flange.
[0122] An ore size regulating apparatus such as a screen or comminuting apparatus 50 is suspended above the slurry box 30 . For example, in the preferred embodiment the comminuting apparatus may be a screening/sizing roller screen such as that described in Canadian Patent Application No. 2,476,194 entitled “SIZING ROLLER SCREEN ORE PROCESSING” published Jan. 30, 2006, which is incorporated herein by reference, which both screens and crushes ore. In the preferred embodiment the comminuting apparatus 50 is supported on the frame 20 of the slurry apparatus 10 , with the output face of the comminuting apparatus 50 in communication with the open top of the slurry box 30 such that comminuted ore fed to the comminuting apparatus 50 is directed into the slurry box 30 under the force of gravity. Alternatively, as screen may be provided to screen the incoming ore flow as an initial step before crushing.
[0123] Because the slurry apparatus 10 according to the invention is movable, it is advantageous to maintain a low centre of gravity in the slurry apparatus 10 and therefore if the comminuting apparatus 50 is suspended above the slurry box 30 it is advantageous to provide the comminuting apparatus 50 as close as possible (vertically) to the open top of the slurry box 30 . The comminuting apparatus 50 may be oriented close to the horizontal, or alternatively may have either a positive or negative angle to the horizontal. In a preferred embodiment the comminuting apparatus 50 is oriented at an angle to the horizontal such that comminuted ore is fed at the higher end of the comminuting apparatus 50 . The comminuting apparatus 50 may be supported on its own separate frame, may be solely supported by a side 24 of the slurry apparatus frame 20 , or may be supported on the slurry box 30 . Alternatively, the comminuting apparatus 50 may be in communication with the slurry box 30 via one or more interposed conveyor mechanisms, such as a transfer conveyor (not shown).
[0124] The comminuting apparatus 50 may alternatively be housed in a separate structure and maintained in communication with the slurry box 30 by a conveying apparatus such as a transfer conveyor (not shown). Similarly, while the illustrated embodiment shows the slurry pump 39 and electrical transformers 9 housed in the structure of the slurry facility 10 , it is possible to house these components in one or more separate structures that are detachably connected to the relevant systems in the slurry facility 10 when the slurry facility 10 is in operating mode. It is advantageous to provide transformers 9 within or immediately adjacent to the slurry facility 10 , which will gradually be moved away from any permanent transformer substation as mining progresses.
[0125] A water supply 60 , for example a hood with a spray header (shown in FIG. 14 ), is positioned to apply hot process water to the ore as it is fed into the comminuting apparatus 50 , assisting in the comminuting process and so that ore is already wetted when it enters slurry box 30 . As is well known in the art, the hot process water is mixed with the ore in a proportion which provides the desired slurry consistency for conditioning during transport to an extraction facility. The water supply 60 may be provided in any convenient location for dispensing the process water over the ore, preferably before comminution or optionally after comminution.
[0126] The slurry box 30 is mounted to the floor 22 of the slurry apparatus frame 20 in the desired position. As illustrated in FIG. 14 , the frame 20 is supported on a first set of spaced apart support points 21 , for example adjacent to the corners where the sides 24 meet the base 22 , which may be mounted on crane mats 23 as in the embodiment illustrated in FIGS. 13 and 14 , to support the frame 20 in stationary mode, or alternatively may be mounted on pontoons 27 or other suitable support. The slurry box 30 may be disposed anywhere within the frame 20 , as long as the centre of gravity CG 1 of the slurry apparatus 10 when the slurry box 30 is filled is within the area bounded by the first set of spaced apart support points 21 (as shown in FIG. 14 ).
[0127] The frame 20 further contains other apparatus incidental to the operation of the slurry facility, which may for example include a gland water supply for the slurry pump 39 , cooling units for conditioning the air within the facility to make it suitable for workers, electrical transformers for powering the equipment used in the slurry facility 10 , safety equipment, overhead cranes for maintenance and so on. The distribution of equipment about the frame 20 of the slurry apparatus 10 determines a first center of gravity CG 1 for the slurry apparatus 10 in a stationary mode, in which the slurry box 30 is filled and operational. Preferably the amount and size of equipment are minimized to keep the weight of the facility 10 as low as possible; for example, the facility 10 may house a single hydrotransport pump 39 (or the hydrotransport pump 39 may be supported on a separate structure as noted above). The heaviest equipment should be as low as possible within the frame 20 , to keep the centre of gravity CG 1 and CG 2 low. In the stationary mode, when the frame 20 is supported on the first set of spaced apart support points 21 and the slurry box 30 is filled with slurry and operational, a considerable additional amount of weight is concentrated in the region of the slurry box 30 , which determines the position of the first center of gravity CG 1 . The frame 20 thus supports all the on-board equipment, plus the weight of the slurry, on the first set of spaced apart support points 21 .
[0128] In a moving mode, with the slurry box 30 empty, the centre of gravity is disposed at CG 2 . The base 22 of the frame 20 is provided with a lifting region 70 , shown in FIG. 15 , which is formed by a series of beams affixed to the main girders 28 of the base 22 . The entire slurry apparatus 10 can thus be lifted by a single moving device such as a mobile crawler 80 , for example that produced by Lampson International LLC (hereinafter referred to as a “Lampson Crawler”), lifting solely at the lifting region 70 , without substantial deformation of the frame 20 . The lifting region 70 defines a second set of spaced apart support points 72 , which is directly beneath (and preferably centered under) the second center of gravity CG 2 . The Lampson Crawler, which is essentially a hydraulic lifting platform having a propulsion system and mounted on tracks as illustrated in FIG. 9B , can be positioned under the lifting region 70 using locator tabs 74 , shown in FIG. 15 , and raised to lift the frame 20 while maintaining the stability of the facility 10 .
[0129] In the operating mode, ore is fed to the comminuting apparatus 50 in any desired fashion, for example via a transfer conveyor 6 as shown in FIGS. 13 and 4 . Preferably the transfer conveyor 6 is freestanding and not connected to the slurry apparatus 10 , but suspended in communication with the slurry apparatus 10 . The ore is processed by the comminuting apparatus 50 , preferably to reduce the particle size of the entire inflow of ore to a maximum of 2″ to 2½″ (although larger ore sizes can also be processed). The comminuting apparatus 50 may include an oversize comminuting component 52 (shown in FIG. 14 ) to comminute oversized ore and eliminate rejected ore.
[0130] The comminuted ore is mixed with water from the water supply 60 and fed into the slurry box 30 . A slurry of the consistency desired for hydrotransport is thus created within the slurry box 30 . The slurry progresses through the slurry box 30 over the selected retention interval and egresses through the slurry outlet to a hydrotransport pump 39 , which in turn feeds the slurry into a hydrotransport outlet 41 to which a line (not shown) is detachably connected for transport to an extraction facility (not shown). The hydrotransport line is detachable from the hydro transport outlet 41 to allow for periodic movement of the slurry apparatus 10 to a new site as the mine face moves away from the slurry apparatus 10 .
[0131] The electrical supplies including all power lines (and optionally telecommunications cables) are preferably contained in a power cable that detachably connects to a local connection (not shown) on the slurry facility 10 , which may for example be adjacent to the transformers 9 , to facilitate easy connection and disconnection of all electrical systems to a standard power source remote to the movable facility 10 . Preferably the electrical power system is grounded via cable to a local transformer station or platform, rather than directly into the ground, either via the power cable or via a separate grounding cable, to facilitate detachment and reattachment of the ground connection during the relocation procedure. Similarly, water supplies and connections to fluid outlets (for example emergency pond outlet 45 ) are not welded but are instead detachably coupled via bolted flanges, quick-connect couplings or other suitable detachable connections as desired to facilitate detachment and reattachment during the relocation procedure.
[0132] When it is desired to move the slurry apparatus 10 to a new location, the transfer conveyor 6 is deactivated to discontinue the ore flow, and the slurry box 30 is empty and flushed. Preferably the slurry apparatus 10 includes a cold water supply 43 for use in flushing the slurry apparatus (and in case of emergency; an emergency outlet 45 is also preferably provided for directing contaminated water to a nearby emergency pond if needed). When the slurry box 30 has been completely emptied and flushed, the hydrotransport line (not shown) is disconnected from hydrotransport pump 39 .
[0133] All electrical and water supplies are disconnected from the apparatus 10 . Once all water supplies and electrical supplies have been disconnected, the slurry apparatus 10 is ready to be moved to a new location.
[0134] A path to the new location is prepared, for example by compacting and laying down a suitable bed of gravel, if necessary. The new location is surveyed to ensure it is level (using gravel if necessary to level the site), and in the embodiment illustrated in FIGS. 13 and 14 crane mats are laid optionally covered by metal sheeting (not shown) to avoid point-loading the crane mats 23 . In this embodiment hydraulic jacks 29 are provided generally under the first set of spaced apart support points, supported on the crane mats 23 . The jacks 29 are actuated, either in unison or individually in increments, to raise the frame 20 to a height that will allow a moving device 80 such as a Lampson Crawler, with its hydraulic platform 82 in retracted mode, to be driven beneath the base 22 of the frame 20 and positioned under the lifting region 70 using locator tabs 74 (shown in FIG. 15 ) as a guide to position the hydraulic platform 82 . The hydraulic platform 82 is raised, lifting the entire frame 20 . When the frame 20 has been raised to support the frame the hydraulic jacks 29 are retracted (as shown in FIG. 16 ), the propulsion system in the Lampson Crawler 80 is engaged and the slurry apparatus 10 is moved toward the new location. Preferably the slurry apparatus 10 comprises on-board levels (not shown) at locations visible from the exterior of the apparatus 10 , and/or a water level comprising a flexible tube filled with water and extending across the entire frame 20 (not shown), which are carefully monitored by operators to ensure that the facility 10 remains level within the tolerances permitted by the second set of spaced apart support points 72 (as described below).
[0135] As illustrated in FIG. 16 the slurry apparatus 10 may be tilted, preferably up to or potentially more than 8° from the vertical, while maintaining the center of gravity in moving mode CG 2 over the lifting region 70 . This allows the slurry apparatus 10 to be moved up or down a grade, and to tolerate variations of the ground surface. The hydraulic lifting platform 82 on the Lampson Crawler also has the ability to lift differentially, and thus compensate to some extent for the angle of a grade as shown in FIG. 16 . However, the slurry apparatus 10 itself may be tilted up to the point where the center of gravity CG 2 reaches the periphery of the lifting region 70 , beyond which the apparatus 10 will become unstable.
[0136] When the new site is reached the hydraulic jacks 29 are extended to support the frame on the crane mats 23 which have been placed on the ground beneath the first set of support points 21 , the hydraulic lifting platform 82 is lowered and the Lampson Crawler is driven away from the site. The slurry facility 10 is fully supported by the first set of spaced apart support points 21 , and can be returned to the operating mode by extending (from the previous site) and reconnecting the hydrotransport line and all electrical and water supplies. An ore feeder such as a transfer conveyor is positioned in communication with the comminuting apparatus 50 , and operation of the slurry facility 10 is resumed. When the slurry box 30 is once again filled with slurry, the center of gravity will shift from CG 2 back to CG 1 , shown in FIG. 14 .
[0137] In a further embodiment of the apparatus, the frame 20 is provided with pontoons 27 onto which the frame 20 is set instead of crane mats 23 . This reduces the steps required to both lift the slurry apparatus 10 and to prepare the new relocation site. This also has the advantage of adding weight to the bottom of the frame 20 , lowering the centres of gravity CG 1 and CG 2 . The operation of this embodiment is otherwise as previously described.
[0138] A suitable system, apparatus and process for extraction is described and claimed in applicant's co-pending application entitled SYSTEM, APPARATUS AND PROCESS FOR EXTRACTION OF BITUMEN FROM OIL SANDS, filed Nov. 9, 2006 and claiming priority from CA2,526,336.
[0139] A preferred embodiment of the invention having been thus described by way of example only, it will be appreciated that variations and permutations may be made without departing from the invention, as set out in the appended claims. All such variations and permutations are intended to be included within the scope of the invention. | A relocatable oil sand slurry preparation system is provided for preparing an aqueous oil sand slurry amenable to pipeline conveyance while producing minimum overall rejects, comprising (a) a relocatable rotary digester for slurrying oil sand and water and digesting oil sand lumps to form a pumpable slurry, the rotary digester having a feed end for receiving oil sand and water, a slurrying chamber comprising a plurality of lifters for slurrying the oil sand and water, and a trommel screen end for screening out oversize rejects from the oil sand slurry which falls through the trommel screen; and (b) a relocatable rejects recirculation unit operably associated with the rotary digester for receiving oversize rejects and delivering the rejects back to the rotary digester for further digestion. In a preferred body, relocatable oil sand slurry preparation system further comprises a rejects crusher for crushing oversize rejects prior to delivering rejects back to the rotary digester. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the removal of stainless steel, zirconium or zirconium alloy cladding materials from a metallic element selected from the group consisting of uranium, thorium and mixtures thereof. The present invention is particularly applicable to the selective destructive removal of cladding materials from nuclear fuel elements containing fissile or fertile fuels such as uranium, thorium and mixtures thereof.
2. Prior Art
There are numerous types of nuclear power fuel elements. The present invention is particularly applicable to those nuclear fuel elements of the solid type which comprise a body or core of thermal neutron fissionable uranium, thorium or mixtures thereof which may be present in an elemental state or alloyed with zirconium, niobium or other low cross section materials which are clad in a low cross section corrosion resistant material such as stainless steel, zirconium, or zirconium alloys.
Nuclear power fuel elements generally contain two types of nuclear fuel material, both of which are valuable. It is essential that the fuel element contain a fissionable nuclear fuel material such as uranium isotopes U 233 or U 235. Fuel elements also contain nuclear fuel materials that are not originally fissionable, but which can be converted to fissionable material and are, therefore, said to be fertile or potential nuclear fuel materials. For example, U 238 is a fertile material often present in fuel elements in considerable amounts. In some instances as much as 99.3% of the uranium content may be present in the form of U 238 in the case of an unenriched element. During the course of the use of the element in a power reactor, the fissionable material such as U 233 and U 235 releases neutrons. Some of the neutrons are trapped by the fertile but unfissionable U 238 present in the element and the U 238 eventually becomes Pu 239 which is fissionable. In the same way, thorium which is a fertile but unfissionable material, absorbs neutrons to become U 233 which is fissionable and useful as nuclear fuel material.
Fuel elements of the solid type, with which the present invention is particularly applicable, deteriorate due to radiation damage long before the useful content of the fissionable material is used. At the same time, radioactive fission products accumulate in the fuel element. Some are gases and others are solid; however, each is objectionable in reducing the efficiency of the reactor as a whole and each exert some part in the destruction or disintegration of the fuel element. More particularly, many of the fission products have a high neutron capture cross section thus reducing the total amounts of neutrons available for production of thermal energy. In addition, the gaseous fission products build up pressure within the cladding material which can result in permanent structural damage to the elements and possibly to the reactor. Since these deleterious effects occur at a time when only a small fraction of the fissile values have been burned by the fission process and since the unburned fuel is too valuable to be wasted, it advantageously is reprocessed to render it fit for reuse.
None of the heretofore known methods for recovering fuel and fertile uranium or thorium from such elements has been completely satisfactory.
One method, for recovering unburned fissile and fertile fuel values from solid neutron irradiated fuel elements, involves dissolution of the cladding and the fuel followed by a liquid-liquid solvent extraction process in which an aqueous nitrate feed solution containing said values is selectively extracted by contact with an organic aqueous immiscible extractant. An example of a solvent extraction process for recovering uranium values, for example, is found in U.S. Pat. No. 2,848,300.
A major disadvantage of aqueous dissolution of cladding, however, is that large aqueous feed volumes containing dissolved metals must be carried through the solvent extraction process. This in turn leads to a large radioactive waste volume requiring expensive waste storage and handling. In addition, the solutions generally are highly corrosive and have a high chloride content. Removal of chloride from the aqueous feed must be accomplished prior to solvent extraction for recovery of the thorium or uranium.
In an attempt to reduce the volume of high level radioactive waste pollution, various other methods have been proposed, such as separately dissolving the cladding material in concentrated sulfuric acid thus making the fuel core available for ready dissolution in a nitric acid solution. However, a cladding material such as stainless steel is relatively passive in sulfuric acid and even when it does react, there is a high probability that cross contamination between the decladding solution and the core solution will result, thus further complicating the problem of recovering the fuel.
U.S. Pat. No. 2,827,405 suggests a method of desheathing fuel rods of uranium metal bars by puncturing the sheath to expose the uranium core at a plurality of points. The rod then is reacted with steam at an elevated temperature to oxidize the uranium and break the bond between the sheath and the uranium. The fuel is recovered as an oxide requiring expensive processing to convert it back to a metal.
Another method suggested in U.S. Pat. No. 2,962,371 comprises reacting the element at an elevated temperature with essentially pure anhydrous hydrogen for a time sufficient to hydride the cladding so that it falls from the core. This invention however, is concerned with zirconium-clad fuel elements although it is suggested that it is also applicable to elements that are clad in alloys of zirconium.
Another process for recovering the core of a zirconium-clad fuel element is disclosed in U.S. Pat. No. 3,007,769. The process comprises immersing the clad element in a substantially neutral solution of ammonium fluoride to effect the dissolution of the zirconium and separate the neutron fissionable material values from the solution.
U.S. Pat. No. 3,089,751 suggests a process for the selective separation of uranium from ferritic stainless steels. In accordance with the process disclosed therein, a nuclear fuel element consisting of a core of uranium clad in a ferritic stainless steel is heated to a temperature in the range of 850° C. to 1050° C. for a period of time sufficient to render the cladding susceptible to intergranular corrosion. The heated element is then cooled rapidly to a temperature range of 850° C. to 615° C. and then to about room temperature. The cooled element then is contacted with an aqueous nitrate solution to selectively and quantitatively dissolve the uranium from the core.
Gas phase processes for effecting the dissolution of fuel or the cladding material are disclosed in U.S. Pat. Nos. 3,149,909; 3,156,526 and 3,343,924. The problem of handling and containing gaseous fuel, however, is even greater than that for liquid phase processes.
U.S. Pat. No. 3,929,961 suggests a method of treating a nuclear fuel element enclosed in a stainless steel metal sheath which comprises disposing the fuel element with a portion thereof in an induction coil, subjecting the induction coil to a radio frequency magnetic field to induce local induction heating of the metal sheath sufficient to raise the temperature of the portion of the sheath within the coil to its melting temperature and effect local melting therein. The fuel element is moved axially relative to the induction coil with continued heating to rupture the metal sheath. The fuel values are subsequently recovered by dissolution.
Thus it is seen that the prior art processes either convert the fuel to an oxide or at some point require liquid or gas phase processing with all of the problems associated therewith.
SUMMARY OF THE INVENTION
The present invention provides a method of treating an assembly comprising an element selected from the group consisting of uranium, thorium and mixtures thereof encased in a cladding of stainless steel or a zirconium alloy to separate the selected element from the cladding. In accordance with the present method, the assembly is subjected to a scoring or perforating step to expose the selected element. Thereafter, the assembly is exposed to hydrogen at a pressure of from about 0.5 to 2.0 atmospheres (360 to 1400 torr) and a temperature of 450° C. to 680° C. to form a hydride of the element. The hydride, having a greater volume than the elemental metal, expands, rupturing the cladding material. Thereafter, the temperature is further increased to a range of from about 700° C. to 900° C. to decompose the hydride back to the element. The dehydriding results in the element being in the form of friable particulates such that after at least one and preferably after about three successive hydriding-dehydriding steps, the selected element is readily recoverable from the cladding material, utilizing conventional mechanical separation techniques such as sieving or the like. In a particularly preferred embodiment of the invention, during the hydriding step, the temperature is cycled between about 500° C. and 650° C. to enhance the completeness of the hydriding and maximize the removal or evolution of any volatile compounds contained within the assembly. The present invention is particularly applicable to the treatment of irradiated fuel elements for the recovery of fissionable and fertile values therefrom.
BRIEF DESCRIPTION OF THE DRAWING
The sole FIGURE of the drawing depicts in the form of a flow sheet the various steps of a process in accordance with a preferred embodiment of the present invention for removing the cladding from an assembly comprising a fuel such as uranium, thorium or mixtures thereof encased in a cladding material of stainless steel, zirconium or zirconium alloys.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention provides a method for the treatment of an assembly comprising a cladding material and a core of uranium, thorium or mixtures thereof to separately recover the cladding material and the core. The method is particularly applicable to the treatment of a nuclear fuel element comprising a cladding material containing a metallic fuel such as fissile or fertile uranium, thorium and combinations thereof. The cladding material generally comprises a stainless steel which consists principally of iron alloyed with chromium and containing minor amounts of other metal additives. The present invention also is applicable to zirconium or zirconium alloy cladding materials. The zirconium alloy generally consists principally of zirconium and contains minor amounts of one or more alloying materials such as nickel, chromium, tin or iron. For convenience, the present invention will be described with respect to its particularly preferred application, namely, the treatment of a nuclear fuel assembly.
Referring to the sole FIGURE, the fuel assembly first is introduced into a cladding piercing zone 10 where at least a portion of the cladding material is pierced, perforated, scored, sheared or the like to at least partially expose the thorium or uranium core. The precise mechanical means used to accomplish the exposure of the core is not particularly critical. However, it generally is preferred to expose at least a portion of the surface of the core at intervals of about 1/2 to 11/2 inches throughout the length of the fuel assembly.
The perforated or scored fuel assembly is next introduced into a hydriding-dehydriding zone 12. It will be appreciated that both the piercing of the cladding and the hydriding-dehydriding could be accomplished in a single zone; however, in accordance with the particularly preferred embodiment set forth herein, each operation is performed in separate zones.
In hydriding-dehydriding zone 12, the assembly is reacted with hydrogen at a hydrogen pressure of from about 0.5 to 2 atmospheres (360 to 1400 torr) and preferably at about one atmosphere (760 torr). Lower pressures substantially reduce the hydriding reaction rate and at higher pressures the reaction rate is not significantly increased. The temperature during the hydriding reaction is maintained within a range of from about 400° C. to 650° C. When the fuel is uranium, the temperature is optimally maintained within a range of about 450° C. to 600° C. and for thorium, a temperature range of from 500° C. to 650° C. is preferred. In accordance with the particularly preferred embodiment, when the core of the assembly comprises uranium, thorium or mixtures thereof, the temperature is cycled during the hydriding process such that the core is exposed to both an optimum hydriding temperature and an optimum hydrogen diffusion temperature. The time required to achieve substantially complete reaction will vary, of course, depending upon the size and shape of the metallic thorium or uranium core as well as the amount of surface area of the core exposed in the cladding and piercing operation. Generally, when the assembly is treated in accordance with the preferred conditions set forth herein, it is found that the reaction is substantially complete in a time of from about 15 to 90 minutes.
Following the hydriding reaction, the temperature in zone 12 is increased to from about 700° C. to 900° C. to decompose the hydride to elemental metal and release the hydrogen which is withdrawn via a pump 14. When the fuel assembly is one which has been irradiated and contains gaseous fission products, the hydrogen withdrawn preferably is introduced into a volatile removal zone 16 where the gaseous stream is treated, for example by condensation, to remove a major portion of the volatile fission products. It is a particular advantage of the present invention that forming the hydride and then dehydriding the product so formed, releases substantially all of the volatile fission products. In addition, during the hydriding step, the hydride is formed as discrete particles of substantially increased volume. These particles of increased volume tend to split or rupture the cladding material and increase the size of the openings therethrough such that after the subsequent dehydriding, the core material is left in the form of small, friable discrete particles which are readily recoverable from the assembly by simple mechanical means such as sieving or mechanical agitation to separate the particulate core material from the larger substantially intact pieces of cladding material. Advantageously, the hydriding-dehydriding step is repeated at least once and preferably twice to ensure complete release of any volatile fission products present as well as to ensure that substantially all of the elemental core material has been exposed to and reacted with hydrogen at least once. The resulting particulate fuel material is readily processible to produce new fuel assemblies by enrichment, if necessary, and sintering or arc casting to reform pellets of the fuel. Thus, it is seen that the present invention provides a method for treating such assemblies without the necessity of complex and expensive gaseous or liquid phase processing. Further, in accordance with the present invention, any plutonium which may be present is never isolated but remains with the fuel in such a dilute form, however, as to substantially negate the possibility of it being used in the production of a nuclear weapon.
The following example is set forth to more clearly illustrate a specific embodiment of the present invention as applied to the decladding of a nuclear fuel element and recovery and separation of the valuable constituents of the core from the undesirable radioactive gaseous fission products.
EXAMPLE
The purpose of this example is to demonstrate the method of the present invention to (1) declad the fuel, (2) cominute the fuel so it will fall free from the cladding, (3) release the volatile fission product, and (4) restore the fuel to its initial chemical form (i.e., metal).
To determine the ability of the present method to release volatile fission products without the necessity of using radioactive materials, it was determined to monitor the radon evolved during the tests. Radon is a decay daughter of thorium, uranium and plutonium that is produced in situ within the fuel, just as xenon and krypton is produced during fission. Calculations indicate that the radon contained in one gram of metallic thorium that had decayed for a year since it was arc cast was sufficient to produce several hundred disintegrations per minute. Therefore, monitoring the radon radioactivity when thorium is pulverized in accordance with the present method would provide an excellent measure of the amount of volatile fission products which would be released during the treatment of the irradiated thorium fuel.
A simulated fuel assembly was built which comprised 1/4×1/4×3-inch square strips of thorium which were rounded and cut into 1/2-inch lengths to simulate fuel pellets. The pellets were loaded into a 4-inch long×1/4-inch O.D. piece of stainless steel tubing which had a wall thickness of 0.112 inches. After the pellets were loaded, the tubing was crimped on each end and a 1/8-inch diameter hole was punched in the tubing at 1-inch intervals along one side. The simulated clad fuel assembly was then treated at various hydriding-dehydriding conditions in accordance with the present invention. After treatment, the assembly was removed from the reaction chamber and examined. The conditions and results are set forth in the following table.
For the tests in the table, it was found that the thorium hydriding and dehydriding temperatures appear to be most rapid around 600° C. and 900° C., respectively. Based on the differential hydrogen pressure in the system, it appears that maximum hydrogen absorption reaction occurred around 600° C. Hydrogen pressure in the closed system increased as a result of the initial heatup of thorium pellets to 350° C. At 350° C., the pressure leveled off and then decreased slowly with continued heating. The decrease in pressure became more pronounced in the 600° C. range and continued to decrease (indicating continued hydrogen absorption and reaction) until a temperature of about 680° C. was reached. Sharp pressure increases were observed when the temperature was increased to above 700° C. Maximum pressure increase was obtained at about 900° C. Thus, hydriding occurs between 350° C. and 680° C. for thorium and is most rapid around 680° C. while dehydriding occurs above 700° C. and is most rapid around 900° C.
Complete pulverization of the thorium metal by repeated hydriding and dehydriding (three cycles) was readily achieved. Comminution of the metal to less than 400-mesh without mechanical treatment was not achieved. However, the dehydrided metal is extremely friable and readily comminuted to a size of less than 400-mesh by ball milling, pressure screening or the like.
TABLE__________________________________________________________________________PROCESSING OF CLAD THORIUM PELLETS Radon Released* Pressure (Torr) Hydriding Dehydriding % of AccumSeries Test No. H.sub.2 Total# Temp °C. Time (hr) Temp °C. Time (hr) Cts Total %__________________________________________________________________________1 a 380 760 520 0.25 850 0.33 45 1 -- b 380 760 600 1 800 1 20 Nil -- c 380 760 560 0.5 800 0.25 4 Nil 1 d 380 760 700 0.25 1000 0.25 Nil -- 1 e 380 760 -- -- -- -- 80 1 2 f 380 760 500 0.5 700 0.25 30 Nil 2__________________________________________________________________________2 a 760 760 525-600 2 800 0.25 60 1 3 b 550 550 -- -- -- -- 170 2 5 c 550 550 500-660 3 700-800 1 2350 24 29 d 550 550 570 0.5 810 0.25 Nil -- 29 e 550 550 660 0.5 710 0.25 Nil -- 29 f 450 450 400-700 3 950 1.0 1500 15 44 g 500 500 -- -- 800 0.5 Nil -- 44 h 150 150 -- -- -- -- Nil -- 44 i 900 900 400-650 2 -- -- 750 7 51 j 400 400 -- -- -- -- -- -- -- Cooled to Room Temperature, Disassembled, Cladding__________________________________________________________________________ Inspected3 a 900 900 550 2 -- -- 700 7 58 b 900 900 400-600 2 900 0.3 1600 16 74 c 900 900 500 1.5 800-900 1.0 900 9 83 d 900 900 650 0.25 870 0.25 Nil -- 83 e 1000 1000 500 0.5 800-900 1.00 400 4 87 f 640-1000 640-1000 500 0.25 900 0.25 1200 12 99 g 1000 1000 460-560 0.5 750 0.25 Nil -- 99 h 1000 1000 -- -- -- -- -- -- 99 Cooled to Room Temperature and Disassembled__________________________________________________________________________ *Total counting rate of radon if completely released = 9850. #Balance of gas was argon.
Substantial amounts of radon were involved during the hydriding-dehydriding of the fuel. The radon counting rate in the hydrogen increased rapidly above 400° C. to a maximum at a temperature of about 900° C. The radon appeared to evolve during both the hydride and dehydride portion of the cycle.
When the foregoing example is repeated, using uranium clad in stainless steel, zirconium or a zirconium alloy, or a mixture of uranium and thorium clad in such alloys, substantially the same results are obtained. Specifically, the uranium, thorium or mixture thereof is reduced to a fine friable particulate form and the cladding material is sufficiently ruptured by the hydride form, so that on subsequent dehydriding, the particles are readily removable from the cladding by mechanical means.
It is readily apparent that the present invention provides an economical, safe and easy to operate method for the recovery and separation of uranium, thorium or mixtures thereof from a cladding material. While the foregoing example and description exemplify what are presently considered to be the preferred embodiments of the invention, it will be appreciated that many changes might be made in the embodiments described. The application of the method of the present invention to other elements clad or sheathed in various metals also will be readily apparent. Thus, the foregoing description is to be construed and interpreted as illustrative only and not in a limiting sense; reference being had to the claims for such latter purpose. | A method of decladding an assembly comprising an element selected from the group consisting of uranium, thorium and mixtures thereof, clad in stainless steel, zirconium, or an alloy consisting essentially of zirconium and containing minor amounts of nickel, chromium, tin, iron or combinations thereof. In a first step the cladding is scored or perforated to expose the selected element. Thereafter, the assembly is exposed to a hydrogen atmosphere at an elevated temperature for a time sufficient for the hydrogen and selected element to react and form a hydride. The temperature then is further increased to decompose the hydride back to gaseous hydrogen and the selected element. The hydriding-dehydriding preferably are repeated at least two additional times to ensure complete release of any volatile gases present. The formation of the hydride which has substantially greater volume than the selected element ruptures the cladding assembly and the subsequent dehydriding leaves the selected element in a friable granular form whereby it is readily separable from the cladding material by conventional mechanical means such as sieving or the like. | 6 |
TECHNICAL FIELD
This invention relates generally to the removal of contaminants from fossil fuels, such as coal and crude oil, in order to reduce the pollution caused by the combustion of such fuels and more particularly this invention relates to the removal of sulphur and other pollutants by a low cost chemical reaction.
BACKGROUND ART
Industry, government and individual citizens have a need for improved energy resources which can meet the energy needs of the nation and yet are environmentally acceptable because they cause the emission of little or no pollution. One of the principal and most objectionable pollutants is sulphur.
The Clean Air Act of 1970 has stimulated research for cleaner fuels. Many experts believe that sulphur compounds released by the combustion of sulphur bearing fuels cause not only the direct effect of polluting air breathed by all citizens but also cause acetic precipitation which has a long range indirect effect on people by injuring or destroying vegetation and aquatic life.
While the United States has very substantial coal reserves, the problems with contaminants have caused restrictions upon the use of coal which in turn have caused economic hardship upon segments of the U.S. population. Therefore an inexpensive method for desulfurizing fossil fuels would increase available energy, improve the environment and the quality of life and be an economic stimulus.
Numerous methods for desulfurizing fossil fuels have been explored. These include physical separation techniques, chemical processes, and bacterial oxidation.
One of the problems with chemical processes is that they often use a variety of solvents, including quinoline, toluene, petroleum ether, and household bleach. They have met with some success under laboratory conditions. However, the difficulty is that chemical processes are not economically acceptable on an industrial scale because of their high cost and the by-product disposal problems which they create. In addition, existing apparatus for removal of pollutants, including sulphur, from fossil fuels is large and bulky, expensive and not,easily moved from one location to another.
It is a purpose of the present invention to provide an apparatus and method for the removal of pollutants, such as sulphur, from oil and coal which invention requires simpler, smaller, equipment and is less expensive than currently available apparatus and techniques. The apparatus of the present invention is capable of being installed in a typical field operation and in a limited space and can easily be moved from one location to another.
BRIEF DISCLOSURE OF INVENTION
In the present invention fossil fuel in a liquid medium, such as crude oil or coal slurry, is exposed to metallic copper surfaces to effect the reaction of sulphur and sulphur compounds in the fuel with copper ions in the liquid to precipitate copper sulfide and then that precipitate is removed. The method is advantageously practiced in a receptacle containing a plurality of preferably parallel copper tubes and connected to a common inlet at one end of the receptacle and a common outlet at the opposite end of the receptacle for conducting a stream of fossil fuel, such as oil or coal slurry, past the copper tubes, both through their interior and about their exterior in order to expose the fuel to the copper surface. Desirably a means for stirring, such as an impeller or rotating paddle wheel, agitates or creates turbulence in the fuel stream to stir the liquid in the receptacle.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a view in perspective of an apparatus embodying the present invention for practicing the method of the present invention.
FIG. 2 is a table of data illustrating the treatment of coal in accordance with the present invention.
FIG. 3 is a table of data illustrating the treatment of crude oil in accordance with the present invention.
In describing the preferred embodiment of the invention which is illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific terms so selected and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose.
DETAILED DESCRIPTION
FIG. 1 illustrates a copper receptacle 10 having an inlet pipe 12 and an outlet pipe 14. In the embodiment utilized to practice the invention for experimental purposes, the receptacle 10 was constructed of 1/4 inch thick copper plate. Mounted within the receptacle 10 are a plurality of parallel copper tubes 16 which, in the experimental embodiment, were one and one-half inch diameter copper tubes.
The fossil fuel in a liquid medium is pumped into the inlet tube 12 and passes both through the interior and about the exterior of the tubes 16 and then out the outlet tube 14 after treatment.
Thus, the fossil fuel in the liquid medium is free to contact the interior surface of the receptacle 10 as well as both the interior and exterior surfaces of the tubes 16.
It is desirable to continuously stir the liquid in the receptacle 10 during the treatment period. This may be accomplished, for example with a coal slurry, by means of an induction coil 18 connected to a suitable alternating source to provide induction stirring. Alternatively, of course, impellers or paddles may be positioned in the receptacle for causing the stirring action, particularly when treating crude oil. Desirably, a lower portion of the receptacle 10 is formed as a sump, particularly when treating crude oil, to collect the waste products which are precipitated during the process.
Desirably this sump is approximately 5% to 10% of the tank volume.
Alternatively, tanks or receptacles of other shapes may be utilized and the active copper surfaces may be provided, for example, by helical tubes with flow being along a helical path. As another alternative copper plates may be suspended within the receptacle.
In practicing the method of the present invention, the fossil fuel as a liquid medium is exposed to metallic copper surfaces in a liquid medium to effect the reaction of sulphur and sulphur compounds in the fuel with the copper. It is believed that small portions of the copper ionize and react with the sulphur and sulphur compounds to precipitate copper sulfide which settles to the bottom of the receptacle, such as the receptacle 10. Desirably, the liquid is stirred during treatment as described above in order to circulate the liquid in contact with the copper to promote ionization and reaction.
Since crude oil is already a liquid, it may be treated in its natural form in accordance with the method of the present invention.
Coal may be treated by grinding it into a fine particulate matter of 15 mesh to 45 mesh and mixing it with water to form a coal slurry.
Preferably, prior to exposing the fuel to the copper surfaces the copper is treated with an acid, such as acetic acid. It is believed that this removes copper compounds from the surface to activate the copper surface. In the test embodiment of the invention acetic acid was used in the form of a component of vinegar.
When treating coal slurry it is desirable to also add approximately 2% of a dilute acid, such as 2% vinegar, to the coal slurry before treatment. This adjusts the ph and assists in removing copper sulfide from the surface of the copper tubes in order to prevent surface passivation of the metallic copper which would halt the reaction.
It is also desirable to mix an alkali, such as sodium carbonate, with the coal slurry at the approximate concentration of 0.0005% by weight. For example, in the test embodiment calcium carbonate was added at a rate of about one pound of calcium carbonate per ton of coal. The calcium carbonate in combination with the vinegar assists in the removal of ash from the fossil fuel.
Additionally, it has been found desirable to mix approximately 2% by weight of copper sulfate with the coal slurry which assists in the removal of inherent moisture and increases the BTU value of the treated fuel.
No such additives are necessary when treating crude oil, but may be used if desired.
It is further desirable to pretreat the copper tubes (in both the oil and coal treatments) with a solution of Sodium Carbonate. This treatment forms a surface coating of basic copper carbonate (commonly known as verdigris) which accelerates the ionization of the surface copper. This will materially expedite the reaction with the sulfur in the substrate. Because copper sulfide is one of the more insoluble substances known in the inorganic field, the reaction is thus driven to substantial completion.
In addition, heating the fossil fuel to within the range of approximately 110° F. and 120° F. will hasten the reaction.
Following treatment of coal in accordance with the present invention, a conventional float/sink treatment of the coal slurry removes rock and similar sediments from the treated coal product.
In practicing the present invention, as with many such processes, the longer the treatment is administered the more effective are the results. However, diminishing returns are reached and I have found that approximately 48 hours of treatment is effective. However, the fuel may be treated for 24 hours with effective results.
Treatment of fossil fuel in accordance with the present invention reduces the sulphur content and increases the BTU value of the fossil fuel. In addition, it improves the pour point of treated oil.
While certain preferred embodiments of the present invention have been disclosed in detail, it is to be understood that various modifications may be adopted without departing from the spirit of the invention or scope of the following claims. | Contaminants, such as sulphur, sulphur compounds and other pollutants are removed from fossil fuels. The fossil fuel in a liquid medium, such as crude oil or a coal slurry, is exposed to metallic copper to react the sulphur with copper ions and settle out the resulting copper sulphide. Additional additives are also disclosed. | 2 |
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates generally to catheters and intravascular medical procedures. More particularly, it relates to methods and apparatus for delivering a stent through a catheter by way of a guidewire delivery device.
BACKGROUND ART OF THE INVENTION
[0002] Intravascular stents are well known in the medical arts for the treatment of vascular stenoses. Stents are prostheses which are generally tubular and which expand radially in a vessel or lumen to maintain its patency. For deployment within the body's vascular system, most stents are mounted onto a balloon angioplasty catheter for deployment by balloon expansion at the site of a dilated stenosis or an aneurysm. Self-expanding stents, which typically expand from a compressed delivery position to its original diameter when released from the delivery device, generally exert a radial force on the constricted portion of the body lumen to re-establish patency. One common self-expanding stent is manufactured of Nitinol, a nickel-titanium shape memory alloy, which can be formed and annealed, deformed at a low temperature, and recalled to its original shape with heating, such as when deployed at body temperature in the body.
[0003] To position a stent across an area of stenosis or an aneurysm, a guiding catheter having a preformed distal tip is percutaneously introduced into the vascular system of a patient by way of, e.g., a conventional Seldinger technique, and advanced within the vasculature until the distal tip of the guiding catheter is seated in the ostium of a desired artery. A guidewire is then positioned within an inner lumen of a dilatation catheter and then both are advanced through the guiding catheter to the distal end thereof. The guidewire must first be advanced out of the distal end of the guiding catheter into the patient's coronary vasculature until the distal end of the guidewire crosses a lesion to be dilated, then the catheter having a stent positioned on the distal portion is advanced into the patient's vasculature over the previously introduced guidewire until the stent is properly positioned across the lesion. Once in position, the stent may be released accordingly.
[0004] It is generally desirable to have catheters which present small cross sectional diameters to enable access into small sized vessels. However, conventional techniques and apparatus typically require the use of a guidewire for the desirable placement of the catheter and stent within the vasculature. Thus, conventional catheters typically require a separate lumen within the catheter body to allow for the passage of a guidewire therethrough. This separate lumen necessarily adds to the cross sectional profile of the device. Yet vasculature having a tortuous path and/or a small diameter, such as the intracranial vasculature, present problems for the conventional stenting catheter. Accordingly, a highly flexible stenting apparatus which is capable of accessing tortuous regions and which presents a small cross section is needed.
SUMMARY OF THE INVENTION
[0005] A highly flexible stent delivery assembly is described below. The assembly has the desirable characteristics of guidewires in traversing tortuous vasculature, including small cross sectioned vessels. The stent delivery assembly of the present invention is thus able to deliver and place a stent anywhere in the vasculature or within the body that is readily accessible by a guidewire but is not normally accessible by a stenting catheter body which would ride over such a guidewire.
[0006] The stent delivery assembly may typically comprise a guidewire body which is preferably covered at least in part by a retractable sheath. A radially expandable stent is disposed directly in contact about the guidewire preferably near or at the distal end of the guidewire. The retractable sheath preferably covers the entire stent during deployment and placement, and is retractable proximally to uncover or expose the stent for radial expansion. A pair of optionally placed radio-opaque marker bands may be located on either side (distally or proximally) or both sides of the stent on the guidewire body.
[0007] The sheath may have a flush port, which is in fluid communication with the distal end of the assembly, located near the proximal end of the sheath. The flush port enables a fluid, e.g., saline, to be passed through the assembly prior to insertion into the vasculature for flushing out air or debris trapped between the sheath and guidewire. It may also be used to deliver drugs or fluids within the vasculature as desired.
[0008] Because the guidewire body, rather than a catheter body, carries and delivers the stent through the vasculature, the stent may be placed almost anywhere in the body accessible by a conventional guidewire. This may include, e.g., the tortuous intracranial vasculature as well as, e.g., the more accessible coronary vasculature. Furthermore, the assembly, which may include the guidewire, sheath, and stent, may be introduced into a wide variety of conventional catheters. This portability allows for flexibility in using the same type of assembly in an array of conventional catheters depending upon the desired application and the region of the body to be accessed.
[0009] The sheath may be made from various thermoplastics, e.g., PTFE, FEP, Tecoflex, etc., which may optionally be lined on the inner surface of the sheath or on the outer surface of the guidewire or on both with a hydrophilic material such as Tecoflex or some other plastic coating. Additionally, either surface may be coated with various combinations of different materials, depending upon the desired results. It is also preferably made to have a wall thickness of about, e.g., 0.001 in., thick and may have an outer diameter ranging from about 0.0145 to 0.016 in. or greater. The sheath may be simply placed over the guidewire and stent, or it may be heatshrinked to conform closely to the assembly.
[0010] The guidewire body may be made of a conventional guidewire or it may also be formed from a hypotube having an initial diameter ranging from 0.007 to 0.014 in. Possible materials may include superelastic metals and alloys, e.g., Nitinol, or metals such as stainless steel, or non-metallic materials, e.g., polyimide. The hypotube may be further melted or ground down, depending upon the type of material used, into several sections of differing diameters. The distal end of the guidewire may be further tapered and is preferably rounded to aid in advancement through the vasculature. Radio-opaque coils may be placed over a portion of distal end to aid in radiographic visualization.
[0011] The stent may be configured to be self expanding from a constrained first configuration when placed upon guidewire to a larger expanded second configuration when deployed. When the sheath is retracted proximally, the stent preferably self expands to a preconfigured diameter of, e.g., about 0.060 in. (1.5 mm), and up to a diameter of about 0.315 in. (8 mm). Various materials may be used to construct the stent such as platinum, Nitinol, other shape memory alloys, or other self expanding materials.
[0012] Other variations may include a guidewire which defines a stepped section near the distal end of the guidewire. The stepped section outer diameter is less than the uniform diameter defined by the remainder of the guidewire. The stent may be placed over this section while maintaining a flush outer diameter which may facilitate delivery of the stent-guidewire assembly not only through catheter body but within the vasculature. The guidewire may be further formed into tapered section distally of the stepped section.
[0013] When in use in tortuous pathways, such as intracranial vessels, the guidewire assembly may be used with the sheath alone or in combination with a delivery catheter. The catheter body may be advanced within the vessel to a treatment location such as an aneurysm. Once the catheter is near the treatment site, the guidewire may be advanced out of the catheter and adjacent the treatment site. The sheath may then be retracted proximally to expose the stent to radially expand into contact with the walls of the vessel. Alternatively, the sheath may be held stationary while the guidewire and stent are advanced to expose the stent, e.g., as when deploying a coil stent. The stent may be self expanding or configured to expand upon the application of an electric current with or without the sheath. In either case, once the stent has been released from the guidewire and expanded, both the guidewire and sheath may be withdrawn into the catheter body and removed from the vicinity. The catheter may be left within the vessel to allow for the insertion of additional tools or the application of drugs near the treatment site.
[0014] Other variations may include an expandable balloon section preferably located distally of the stent. In this case, treatment preferably includes the expansion of the balloon first to mitigate any occlusions within the vessel. The stent may then be released in a manner similar to that described above. Once the balloon has been deflated and the stent expanded, the assembly may be removed from the vicinity.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1A shows a variation on the stent delivery assembly where a guidewire has a stent disposed on the wire near its distal end.
[0016] FIG. 1B shows another variation on the assembly where the guidewire may have an expandable balloon located near the distal end of the wire.
[0017] FIG. 2 shows a representative illustration of the guidewire and stent assembly which is insertable within a catheter; the assembly shows the guidewire surrounded by a partially retracted sheath which exposes the stent.
[0018] FIG. 3 shows a cross sectioned side view of a variation of the stent delivery assembly placed within a catheter body lumen.
[0019] FIG. 4 shows a cross sectioned side view of another variation of the stent delivery assembly also placed within a catheter body lumen.
[0020] FIG. 5 shows a cross sectioned side view of yet another variation of the stent delivery assembly having an expandable balloon section.
[0021] FIGS. 6A to 6 C illustrate an example of one method of placing a stent within a hollow body organ using the guidewire assembly.
[0022] FIGS. 7A to 7 C illustrate an example of another method of placing a stent within the hollow body organ in combination with an expandable balloon.
DETAILED DESCRIPTION OF THE INVENTION
[0023] A stent delivery assembly having a small cross section and which is highly flexible is described herein. As shown in FIG. 1A , catheter assembly 10 is comprised of a conventional catheter body 12 having a distal end 14 and a proximal end 16 . A fitting assembly 18 is attached to the proximal end 16 and may preferably have various attachments, e.g., Luer lock 20 , to allow for access to catheter body 12 or the use of other instruments. Conventional catheter body 12 shows guidewire assembly 22 being slidably positioned therewithin. Assembly 22 , which is described in further detail below, is shown in this variation as having a guidewire body 24 preferably covered at least in part by a retractable sheath 26 . A radially expandable stent 28 is preferably disposed near the distal end of guidewire 24 . Stent 28 may also be placed between an optional pair of radio-opaque marker bands 30 , 32 . One or both marker bands 30 , 32 may be used or they may be left off the assembly entirely. The use of radio-opaque material allows for the visualization of the assembly during placement within the vasculature. Such visualization techniques may include conventional methods such as fluoroscopy, radiography, ultrasonography, magnetic resonance imaging, etc.
[0024] FIG. 1B shows the distal portion of catheter body 12 with another guidewire variation 34 which has an optional angioplasty balloon 36 . As shown in this variation, balloon 36 is preferably located distally of stent 28 and may be sufficiently deflated such that sheath 26 may be placed over both stent 28 and balloon 36 .
[0025] FIG. 2 shows a representative illustration of the stent delivery assembly 40 removed entirely from the delivery catheter body with guidewire 24 covered by sheath 26 . Stent 28 is preferably placed directly over guidewire body 24 and is covered by sheath 26 . Sheath 26 may have a flush port 42 located near the proximal end of the sheath 26 . Flush port 42 is preferably in fluid communication with the distal end of the assembly 40 so that a fluid, e.g., saline, may be passed through the assembly 40 prior to insertion into the vasculature for flushing out air or debris trapped between the sheath 26 and guidewire 24 . Flush port 42 may also be used to deliver drugs or fluids within the vasculature as desired.
[0026] Because the guidewire body 24 , rather than a catheter body, carries and delivers stent 28 through the vasculature, the stent 28 may be placed almost anywhere in the body accessible by a conventional guidewire. This may include, e.g., the tortuous intracranial vasculature as well as, e.g., the more accessible coronary vasculature. Furthermore, assembly 40 , which may include the guidewire 24 , sheath 26 , and stent 28 , may be introduced into a wide variety of conventional catheters. This portability of assembly 40 allows for flexibility in using the same type of assembly 40 in an array of conventional catheters depending upon the desired application and the region of the body to be accessed.
[0027] The sheath 26 may be made from various thermoplastics, e.g., PTFE, FEP, Tecoflex, etc., which may optionally be lined on the inner surface of the sheath or on the outer surface of the guidewire or on both with a hydrophilic material such as Tecoflex or some other plastic coating. Additionally, either surface may be coated with various combinations of different materials, depending upon the desired results. Sheath 26 is preferably made to have a wall thickness of about 0.001 in. thick, and optionally thicker, and may have an outer diameter ranging from about 0.0145 to 0.016 in., or greater. Sheath 26 may also be placed over guidewire body 24 having a diameter of about 0.038 in. When placed over guidewire body 24 and stent 28 , it may be simply placed over to slide along wire 24 or it may also be heatshrinked over the wire 24 and stent 28 to conform closely to the assembly.
[0028] A more detailed view of the guidewire assembly is shown in the cross sectioned side view in FIG. 3 . As seen, the distal end of guidewire body 24 is shown loaded within sheath lumen 60 of sheath 26 and this assembly is shown as being disposed within catheter lumen 62 of catheter body 12 . As previously discussed, because stent 28 is placed upon a guidewire body rather than a catheter body, the assembly may be introduced into any part of the body which is accessible by a conventional guidewire but which is not normally accessible for stenting treatments.
[0029] The guidewire body 24 may be made of a conventional guidewire and it may also be formed from a hypotube having an initial diameter ranging from 0.007 to 0.014 in. The hypotube or guidewire may be made from a variety of materials such as superelastic metals, e.g., Nitinol, or it may be made from metals such as stainless steel. During manufacture, a proximal uniform section 50 of the hypotube may be made to have a length of between about 39 to 87 in. (100 to 220 cm), preferably between about 63 to 71 in. (160 to 180 cm), having the initial diameter of 0.007 to 0.022 in., preferably 0.008 in. The hypotube may be further melted or ground down into a tapered section 52 , depending upon the type of material used, which is distal to the proximal uniform section 50 . Tapered section 52 may have a length of about 4 in. (10 cm) to reduce the diameter down to about 0.002 to 0.003 in. The hypotube may be further formed to have a distal uniform section 54 of about 2 in. (5 cm) in length over which the stent 28 is preferably placed. Radio-opaque marker bands may optionally be placed either distally 30 or proximally 32 of stent 28 to visually aid in the placement of the stent 28 , as is well known in the art. Alternatively, distal and proximal marker bands 30 , 32 may be eliminated altogether. Marker bands 30 , 32 may be used as blocks or stops for maintaining the stent in its position along guidewire body 24 . Alternatively, if bands 30 , 32 are omitted from the device, stops or blocks may be formed integrally into the guidewire body 24 or they may be separately formed from material similar to that of guidewire body 24 and attached thereto.
[0030] Distal end 56 may be further tapered beyond distal uniform section 54 to end in distal tip 58 , which is preferably rounded to aid in guidewire 24 advancement. A coil, preferably made from a radio-opaque material such as platinum, may be placed over a portion of distal end 56 . Alternatively, a radio-opaque material, e.g., doped plastics such as bismuth or tungsten, may be melted down or placed over a portion of distal end 56 to aid in visualization. Stent 28 is preferably made to be self expanding from a constrained first configuration, as when placed upon guidewire 24 for delivery, to a larger expanded second configuration as when deployed within the vasculature. Stent 28 may be constrained by sheath 26 to a diameter of, e.g., 0.014 in., while being delivered to a treatment site within the body, but when sheath 26 is retracted proximally, stent 28 preferably self expands to a preconfigured diameter of, e.g., about 0.060 in. (1.5 mm), and up to a diameter of about 0.315 in. (8 mm). Various materials may be used to construct stent 28 such as platinum, Nitinol, other shape memory alloys, or other self expanding materials. Sheath 26 may also have drainage ports or purge holes 64 formed into the wall near the area covering stent 28 . There may be a single hole or multiple holes, e.g., three holes, formed into sheath 26 . Purge holes 64 allow for fluids, e.g., saline, to readily escape from inbetween sheath 26 and guidewire 24 when purging the instrument, e.g., to remove trapped air or debris.
[0031] FIG. 4 shows a cross sectioned side view of another variation 70 of the stent delivery assembly. As shown, guidewire variation 70 is shown as being surrounded by sheath 26 and the sheath-guidewire assembly is shown as being placed within catheter lumen 62 prior to delivery of the stent. In this variation, the guidewire may have a uniform section 72 like that described in FIG. 3 above. However, there is also a stepped section 74 defined in the guidewire outer diameter near the distal end of the guidewire. Within this section 74 , the stepped outer diameter is less than the uniform diameter defined by the guidewire uniform section 72 . It is over this stepped section 74 that stent 84 may be placed along with optional distal and/or proximal marker bands 80 , 82 , respectively, such that sheath 26 remains flush over this section. Maintaining a flush outer diameter may facilitate delivery of the stent-guidewire assembly not only through catheter body 12 but within the vasculature. The guidewire may be further formed into tapered section 76 distally of stepped section 74 . And the guidewire may be finally formed into a distal tip 78 over which coil 86 may be optionally placed. Coil 86 may optionally be covered by a covering 88 , e.g., a polymer or other plastic material, placed or heatshrinked over the coil 86 and distal tip 78 to provide a smooth section.
[0032] FIG. 5 shows a cross sectioned side view of yet another variation of the stent delivery assembly having an expandable balloon section. As shown, much of the guidewire is similar to variations described above but with the addition of an expandable balloon 36 which may be inflated to an expanded balloon 36 ′. The variation shown may have a uniform section 90 which similarly tapers down 92 into a distal uniform section 94 , over which stent 28 may be placed. Although balloon 36 may be placed proximally of stent 94 , it is preferably located distally of stent 94 , as shown. When deflated, retractable sheath 26 may also be placed over balloon 36 to provide a uniform profile. To accommodate the inflation and deflation of balloon 36 , a small inflation lumen (not shown) may be defined within the body of the guidewire for the passage of fluids into and out of the balloon 36 . A coil may also be optionally placed over distal end 96 ; alternatively, a radio-opaque material may be melted down or placed over distal end 96 .
[0033] In operation, the stent delivery guidewire may be used with or without the catheter body to deliver the assembly intravascularly. It is preferable that a catheter be used to provide a pathway close to the treatment site. However, in tortuous pathways, such as intracranial vessels, the guidewire device may be used with the sheath alone if the catheter body presents too large a cross section for delivery purposes. FIGS. 6A to 6 C show an example of the deployment of the guidewire assembly. Catheter body 12 may first be advanced within the lumen 102 of vessel 100 to a treatment location, e.g., aneurysm 104 . Once catheter body 12 has reached a position near aneurysm 104 , guidewire 24 may be advanced through and out of catheter 12 with sheath 26 covering stent 28 , as seen in FIG. 6A . As guidewire 24 is advanced, stent 28 located on guidewire 24 may be positioned via radio-opaque marker bands 30 , 32 to the desired location, such as over the neck 106 of aneurysm 104 . Once guidewire 24 and stent 28 have been properly positioned, sheath 26 may be retracted proximally to expose stent 28 to the vascular environment, as shown in FIG. 6B .
[0034] Stent 28 , as shown in FIG. 6C , may be left to radially self expand into gentle contact with the walls of vessel 100 to occlude the neck 106 of aneurysm 104 (as is well known in the art). Stent 28 may also be configured to expand upon the application of an electric current actuated from a location external of the patient. The current may be delivered to stent 28 via an electrical connection or line (not shown) disposed within the body of guidewire 24 . Once the stent 28 has been released from the guidewire body 24 and expanded into contact with vessel 100 , guidewire 24 and sheath 26 may be withdrawn into catheter body 12 and removed entirely from catheter 12 or the catheter 12 itself may then be removed entirely from the body of the patient. If guidewire 24 and sheath 26 are removed only, catheter 12 may be left in position within vessel 100 to allow for the insertion of additional tools or the application of drugs near the treatment site.
[0035] Treatment may also be accomplished with the guidewire variation having an expandable balloon section. FIG. 7A shows vessel 110 which is stenosed with an obstruction 112 . Once catheter body 12 has been positioned within vessel 110 , guidewire body 34 may be advanced out of catheter 12 while still covered by sheath 26 . Balloon 36 may then be positioned adjacent to the obstruction 112 optionally guided by marker bands 30 , 32 . Once positioned, balloon 36 may be expanded to balloon 36 ′, as shown in FIG. 7B , to open the stenosed vessel. After the obstruction 112 has been opened, balloon 36 may be deflated and the guidewire body 34 may be advanced distally to position sheath 28 adjacent to obstruction 112 . Sheath 26 may then be retracted to expose stent 28 to expand, as described above, into contact against obstruction 112 and vessel 110 . FIG. 7C shows the placement of guidewire 34 and expanding stent 28 over obstruction 112 .
[0036] The applications of the guidewire assembly and methods of use discussed above are not limited to the deployment and use within the vascular system but may include any number of further treatment applications. Other treatment sites may include areas or regions of the body such as organ bodies. Modification of the above-described assemblies and methods for carrying out the invention, and variations of aspects of the invention that are obvious to those of skill in the art are intended to be within the scope of the claims. | A method of delivering a stent comprising providing an elongate guide having a stent coaxially supported on the guide for placement and movement by the guide, providing a tubular sheath member, advancing the elongate guide into the body to provide initial access to a preselected treatment site within the body and to carry and deliver the stent to position the stent at the treatment site, and exposing the stent from the tubular sheath member to enable the stent to move from a first reduced diameter position to a second expanded position. | 0 |
This invention relates generally to automatic test equipment and more particularly to tooling pin hardware for positioning and holding a test fixture for a printed circuit board under test.
FIG. 1 shows a test system receiver 120 that may be used to hold a test fixture (not shown) in a fixed position during testing of a printed circuit board. Such a receiver is found in the SPECTRUM™ 8800-Series of printed circuit board testers sold by TERADYNE®, Inc., Walnut Creek, Calif., USA. In particular, the receiver 120 includes quadrants 101, 102, 103, and 104 as generally shown in FIG. 1. Further, the receiver 120 includes multiple tooling pins, such as the pins 100, that may pass through locating holes in the test fixture, thereby holding the test fixture in a fixed position during the test.
The receiver 120 can hold test fixtures of different sizes. Further, when a test fixture is placed upon the receiver 120, a pair of tooling pins 100 typically pass through holes located at diagonally opposing corners of the test fixture.
Accordingly, a small test fixture (not shown) might be placed upon quadrant 101 and held in a fixed position by the pins 100 in diagonally opposing corners of quadrant 101. Similarly, a test fixture of intermediate size (not shown) might be placed upon quadrants 101 and 102 and held in position by the pins 100 in the lower right-hand corner of quadrant 101 and the upper left-hand corner of quadrant 102. Further, a large test fixture (not shown) might be placed upon the quadrants 101, 102, 103, and 104, and held in position by the pins 100 in the lower right-hand corner of quadrant 101 and the upper left-hand corner of quadrant 103.
One shortcoming of the receiver 120 is that the intermediate size test fixture must have an additional hole to provide clearance for the pin 100 in the upper left-hand corner of quadrant 101. Similarly, the large test fixture must have additional holes to provide clearance for the pins 100 in the upper left-hand corner of quadrant 101 and the upper left-hand corner of quadrant 102.
Because a pair of tooling pins passing through holes located at diagonally opposing corners of a test fixture is usually sufficient to hold the test fixture in a fixed position on a receiver during a test, it may be redundant to provide clearance holes for tooling pins at other locations on the test fixture. Further, these clearance holes take up space that might otherwise be used by conductive traces on the test fixture. Still further, such clearance holes generally add to the cost of a test fixture because additional manufacturing steps are required to form them.
A tooling pin assembly is described in U.S. Pat. No. 5,395,099 issued Mar. 7, 1995. That patent discloses a tooling pin assembly for positioning a printed circuit board relative to a test platen. Further, the tooling pin assembly has a spring that is biased to push the tooling pin outward. For example, the spring-biased tooling pin may be depressed into the assembly so that the tooling pin is out of the plane of the test platen. Further, when the depressed tooling pin is aligned with a locating hole in a printed circuit board under test the spring forces the tooling pin outward into and through the locating hole.
However, this approach also has some shortcomings. For example, if the depressed tooling pin is not aligned with holes located at diagonally opposing corners of the BUT and is instead aligned with some other intermediate location on the BUT where there is no hole, then the spring may cause the tooling pin to push against the BUT, thereby damaging the BUT. Even if the BUT were not damaged, the spring-loaded tooling pin might cause the BUT to move from its proper position relative to the test fixture interface. Further, such a spring-loaded tooling pin most likely would not be strong enough to hold and position a test fixture, which in some cases can weigh over 100 lbs.
It would therefore be desirable to have a test system receiver with tooling pins that can hold and position a test fixture during a test. Such a receiver would be able to hold and position test fixtures of various sizes without requiring clearance holes for tooling pins at intermediate locations on the test fixtures.
SUMMARY OF THE INVENTION
With the foregoing background in mind, it is an object of the invention to provide a test system receiver that can hold a test fixture in a proper fixed position relative to a tester interface.
Another object of the invention is to provide a receiver that can accommodate test fixtures of various sizes during testing.
Still another object of the invention is to provide a receiver that is easy and inexpensive to manufacture.
The foregoing and other objects are achieved in a test system receiver having tooling pin assemblies located at a plurality of locations on the receiver. The tooling pin assemblies are located to allow the receiver to hold and position test fixtures of various sizes relative to a tester interface. Each tooling pin assembly includes a bushing attached to the receiver with a plug at one end; a screw positioned coaxially with the bushing having a shank portion passing through the plug and a threaded portion located substantially within the bushing; and, a locating pin with a threaded core for receiving the threaded portion of the screw. By rotating the screw, the locating pin can either be lowered into the bushing or raised out of the bushing. In the lowered position, the locating pin is out of the plane of the receiver. In the raised position, the locating pin passes through a hole in the receiver a sufficient amount for holding and positioning a test fixture.
According to one feature, the locating pin is a steel, diamond-shaped pin.
According to another feature, the bushing includes hard stops for the locating pin in both the raised and lowered positions.
Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood by reference to the following more detailed description and accompanying drawings in which
FIG. 1 is a perspective view of a conventional test system receiver;
FIG. 2A is a perspective view of a portion of a test fixture resting on a test system receiver in accordance with the present invention;
FIG. 2B is a cross-sectional view of a tooling pin assembly in accordance with the present invention taken along line 2B--2B of FIG. 2A;
FIG. 2C is a cross-sectional view of a tooling pin assembly according to the present invention taken along line 2C--2C of FIG. 2A; and
FIG. 3 is a top view of the test fixture and one of the tooling pin assemblies shown in FIG. 2A.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 2A shows a test system receiver 220 in accordance with the invention. The receiver 220 includes quadrants 201 (not shown), 202 (not shown), 203, and 204, which generally correspond with quadrants 101, 102, 103, and 104 shown on prior receiver 120 in FIG. 1.
The receiver 220 also includes a plurality of novel tooling pin assemblies 200 located at useful positions on the receiver 220. The locations of the tooling pin assemblies 200 on the receiver 220 generally correspond with the locations of tooling pin assemblies 100 on the prior receiver 120. These locations preferably correspond with locating holes in diagonally opposing corners of test fixtures of various sizes.
The receiver 220 may be used with test fixtures of the type that incorporate a printed wiring board having pads on its lower side for making electrical contact with probes on a tester interface, and probes on its upper side for making electrical contact with pads on a printed circuit board under test (BUT). Such test fixtures are commonly known as "wireless" test fixtures.
Accordingly, a wireless test fixture 230 is shown resting on the receiver 220 and generally covering quadrants 201 and 202 (not shown) of the receiver 220. The test fixture 230 includes contact pads (not shown) on its lower surface (not shown) and probes 238 on its upper surface. The probes 238 typically make electrical contact with selected nodes on a BUT (not shown), which is generally a printed circuit board assembly with many electronic components (not shown) attached to it. In this way, the test fixture 230 may apply and measure signals or levels at the selected nodes during testing. For example, the test fixture 230 may be used to perform in-circuit or functional testing on the BUT.
The test fixture 230 includes locating holes 232 and 234 preferably located at diagonally opposing corners of the test fixture 230. The diameters of the locating holes 232 and 234 are shown exaggerated for clarity. In the preferred embodiment, the diameters of the locating holes 232 and 234 are sufficient to provide clearance for locating pins included in the tooling pin assemblies 200 while allowing the locating pins to hold the test fixture 230 in a fixed position relative to the tester interface during testing.
FIG. 2B shows a cross-sectional view of the tooling pin assembly 200 corresponding to the locating hole 232 in the upper left-hand corner of the test fixture 230. The tooling pin assembly 200 is shown with a fully extended locating pin 202 passing through both an opening in the receiver 220 and the locating hole 232 in the test fixture 230.
The locating pin 202 preferably includes an elongated portion 202B and a portion 202C having a diameter slightly larger than that of the elongated portion 202B, thereby forming a step 218 (see FIG. 2C). Further, the locating pin 202 has a threaded core 202A extending through the portion 202C and extending substantially through the elongated portion 202B for receiving a threaded portion 212A of a screw 212.
Both the locating pin 202 and the screw 212 are supported by a bushing 204, which also serves as a guide for the locating pin 202. The bushing 204 is attached to the receiver 220 in any suitable manner. For example, a rim portion 204A (see FIG. 2C) of the bushing 204 is shown attached to the receiver 220 by screws 214. Further, the rim 204A of the bushing 204 forms a step 221 (see FIG. 2C). The bushing 204 may be made of any suitable material, such as bronze.
A plug 206 has an opening that is sized to receive a shank portion 212B of the screw 212 while allowing enough clearance for the shank 212B to rotate. The free end of the shank 212B preferably has features (not shown) that allow a tool (not shown) to grasp the shank 212B and rotate the screw 212. Further, the shank 212B includes an annular portion 212C.
In the preferred embodiment, the tooling pin assembly 200 is assembled by inserting the shank 212B into the opening of the plug 206 until the annular portion 212C is flush with the surface of the plug 206. A retaining ring 210 is then pressed onto the shank 212B. The annular portion 212C of the shank 212B and the retaining ring 210 therefore secure the screw 212 to the plug 206.
Next, the threaded portion 212A of the screw 212 is screwed into the threaded core 202A of the locating pin 202 preferably until the locating pin 202 makes contact with the plug 206 (see FIG. 2C). The locating pin 202 and the screw 212 in combination are then inserted into the bushing 204, and the plug 206 is pressed into the bushing 204 until it is flush with the edge of the bushing 204. Consequently, the locating pin 202 and the screw 212 extend substantially through the bushing 204.
Finally, the bushing 204 is attached to the receiver 220 at one of the useful positions mentioned above. For example, FIG. 2B shows the tooling pin assembly 200 attached to the receiver 220 so that the locating pin 202 is in registration with the hole 232. Similarly, FIG. 2C shows the tooling pin assembly 200 attached to the receiver 220 so that the locating pin 202 is in registration with a hole 240 (also shown in shadow in FIG. 2A) in the receiver 220.
FIG. 3 is a top view of a portion of the test fixture 230 encompassing the locating hole 232. The rim 204A of the bushing 204 and the screws 214 attaching it to the underside of the receiver 220 are shown in shadow. Further, a top view of the locating pin 202 and the screw 212 in core 202A are shown.
FIG. 3 shows that the locating pin 202 is preferably diamond-shaped. This aids the locating pin 202 in holding the test fixture 230 in a fixed position relative to the tester interface during a test. Further, both the locating pin 202 and the screw 212 may be made of any suitable material. For example, the locating pin 202 may be a steel diamond pin; and, the screw 212 may be made of bronze.
A human operator can use the receiver 220 to hold and position a test fixture as follows. First, the operator uses an appropriate tool to rotate screws 212 in respective tooling pin assemblies 200 attached to the receiver 220, thereby lowering corresponding locating pins 202 into the bushings 204 of the respective tooling pin assemblies. The plug 206 provides a hard stop for the locating pin 202 in its lowered position. Consequently, each of the locating pins 202 is out of the plane of the receiver 220. FIG. 2C shows a tooling pin assembly 200, in registration with the hole 240 in the receiver 220, with the locating pin 202 in its lowered position within the bushing 204 and against the plug 206.
Next, the operator chooses a test fixture such as the test fixture 230 and raises the locating pins that will be used to hold and position the chosen test fixture. For example, the operator rotates the screws 212 of the tooling pin assemblies 200 that will be in registration with locating holes in the chosen test fixture, thereby raising the corresponding locating pins 202 out of the bushings 204. The operator then places the chosen test fixture on the receiver, thereby causing the raised locating pins to pass through the locating holes in the test fixture.
For example, FIG. 2A shows locating pins 202 in their raised positions passing through the locating holes 232 and 234 of the test fixture 230. Further, FIG. 2B shows a tooling pin assembly 200, in registration with the locating hole 232, with the locating pin 202 in its raised position. The step 221 formed by the rim 204A provides a hard stop for the step 218 formed by the lower portion 202C of the locating pin 202.
In this way, the tooling pin assemblies 200 in opposing corners of the test fixture 230 are manipulated to hold the test fixture 230 in a fixed position relative to the tester interface. Further, because the tooling pin assembly 200 in registration with the hole 240 has a locating pin 202 below the plane of the receiver 202, a clearance hole through the test fixture 230 is not required at this location. In fact, the locating holes 232 and 234 are the only holes that are required through the test fixture 230 to secure it to the receiver 220. This eliminates the need to form additional holes through the test fixture 230, and ensures that a maximum amount of the test fixture 230 is available for conductive traces.
Having described one embodiment, numerous alternative embodiments or variations might be made. For example, it was described that the receiver 220 includes quadrants 201, 202, 203, and 204. However, this was merely an illustrative example to facilitate the demonstration of the benefits of the receiver 220 over the prior receiver 120. The test system receiver of the present invention may include more or fewer quadrants depending upon the sizes of the test fixtures it is designed to hold.
In addition, it was described that the receiver 220 includes a plurality of tooling pin assemblies 200 at locations corresponding with the locations of the tooling pin assemblies 100 on the prior receiver 120. However, this was also merely an illustrative example and other locations for the tooling pin assemblies are possible.
In addition, it was described that the receiver 220 is for holding and positioning a test fixture 230. However, this was merely an illustrative example. The test system receiver of the present invention may also hold "personality plates," which are typically used as adapters for various test fixtures.
In addition, it was described that the locating pin 202 and the screw 212 are supported and guided by the bushing 204. In an alternative embodiment, the bushing 204 may be designed to be sealed. This is especially advantageous when the receiver 220 is used with the TERADYNE® SPECTRUM™ 8800-Series of printed circuit board testers, which have a vacuum-actuated tester interface. Further, the sealed bushing helps keep the steel diamond pin in a proper orientation relative to the test system receiver.
In addition, it was described that the bushing 204 and the screw 212 may be made of bronze, the locating pin 202 may be made of steel, and screws may be used to attach the bushing 204 to the receiver 220. However, this was also merely an illustrative example. The bushing, the screw, and the locating pin may be made from different materials, and the bushing may be attached to the receiver in a different manner, so long as the resulting tooling pin and receiver combination is strong and durable enough to hold test fixtures of substantial size and weight.
Therefore, the invention should be limited only by the spirit and scope of the appended claims. | A tooling pin assembly used with a receiver in a printed circuit board tester is disclosed. The tooling pin assembly includes a locating pin with a core threaded to receive a screw, and a bushing for supporting and guiding the locating pin relative to the receiver. When the screw is rotated in one direction, the locating pin moves out of the bushing and passes through a hole in the receiver for engaging a test fixture. When the screw is rotated in the opposite direction, the locating pin retracts into the bushing until it is below the plane of the receiver. The ability to extend and retract the locating pin is especially useful when the tooling pin assembly is used with a receiver designed to hold test fixtures of various sizes. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is the 35 USC 371 National Stage of International Application PCT/DE02/04019 filed on 25 Oct. 2002, which designated the United States of America.
FIELD OF THE INVENTION
The invention relates to a reconfigurable digital logic unit.
BACKGROUND OF THE INVENTION
Conventional programmable logic modules such as processors run programs which are loaded from a memory. These memories may be in the form of discrete modules (for example a hard disk, a memory chip), or may be integrated in the processor. One known example of the former is the known IBM-compatible PCs, and an example of the latter is so-called flash microprocessors. The software to be run is stored in the form of command words as a machine command in the memory. The command words are loaded, analyzed and carried out in a processing unit. The processing of a single command word initiates a large number of individual actions in the logic unit.
One critical characterizing feature of conventional programmable logic modules is that the processing unit is reprogrammed for a number of clock cycles by each new command word. The information relating to the previous command word is overwritten in the processing unit, apart from register contents. The processing unit in modern microprocessors is highly complex in design, owing to the large number of possible operations. More than 30 million transistors are required for fewer than 500 possible command words, which leads to a correspondingly high power consumption since each transistor consumes energy even when it is not being used and is in the “waiting state”. It has already been proposed that the operating voltage be adapted, that is to say reduced, in order to save energy. The clock frequency can likewise be reduced, although this reduces the overall performance of the logic unit.
The complexity for the design, manufacture and testing of these transistors is immense. Once the functionality has been designed, it cannot be changed. Only one task can be processed at a specific time.
Particularly when running through program loops, only a small portion of the processor is active. Most applications contain a large number of program loops, with each loop containing only a relatively small number of commands embedded in the loop. These may be counting loops, for example in order to count the number of rinsing processes in a washing machine. Conditional loops are likewise very frequent, in which the number of repetitions is not known when the loop is entered, since the loop is left as a function of a result. If the event does not occur, the previous commands in the loop are repeated.
Known digital logic units, in particular computers with microprocessors, are based on the concept of the von-Neumann computer. The central processing unit, that is to say the computer core, comprises the major components formed by the main memory, the control unit and the processing unit (arithmetic unit). The main memory stores command words (program data) and processing data (operand words), and makes them available on request. The main memory also holds intermediate results and final results from the processing. Main memories may be formed by volatile or non-volatile memories. The control unit organizes the sequence in which command words are processed. It requests command words from the main memory, and causes the command word to be carried out in the processing unit. It analyzes command words, and causes processing data to be supplied to the processing unit. The processing unit carries out the operation on the processing data, and supplies the results to the main memory. The processing unit contains a microprogram for each operation, which releases the required transmission lines. The processing unit is set by the control unit for the respective operation, that is to say for the command to be processed. This central processing unit has associated peripherals, which may be the abovementioned external memories, input and output appliances. The described main components of the central processing unit may be physically separated, but they are generally on a common processor chip with a cache, or, for example, on an embedded ROM.
Particularly in the case of frequently recurring actions, for example when running through program loops, the known digital logic units have the disadvantage that command words are loaded and carried out which were actually available a number of processor clock cycles previously in a command register. One example of a loop such as this is a keyboard check. When no key is depressed, all the loop commands are repeated at a short interval, in which case the command words have to be reloaded on each occasion, as if they were completely new. The vast majority of the processor is not required during this waiting time, but it cannot carry out any other tasks during this time.
The utilization level of a logic unit such as this is extremely poor since less than one thousand of the available hardware is used. The majority of the chip area remains unused, but power must nevertheless be supplied continuously for operation.
The matching of processors to different circumstances has already been implemented at a low complexity level. One example of this is the switching of memory banks for a processor, which contain different programs. Memory banks which are not in use at any given time can be changed. This technique is referred to as IAP (in application programming). The improvement that is achieved by this measure is comparatively minor, since nothing to do with the processor hardware has been changed, but only the programs to be run being loaded at the same time as other processes.
Programmable logic modules (PLD) are frequently used for less complex tasks. Logic modules such as these are known, for example, from U.S. Pat. No. 4,870,302 or from the publication “Ranmuthu, I. W., et al.; Magneto-resistive elements—An Alternative to Floating Gate Technology; In: Proceedings of the Midwest Symposiums on Circuits and Systems, 1992, pages 134–136 vol. 1”. The entire application program in logic modules such as these is translated to suitable commands in a specific compiler (so-called fitter). The PLD is defined with this program data only once, generally on booting up: a program is read from a program memory, and configurable areas are configured. The configurable areas have the following characteristics: they either define links between predetermined points (routing areas) or process logic input signals to form logic output signals (logic cell areas) However, if connections are required which differ from the technical PLD presets implemented by the manufacturer, two or more connection blocks must be cascaded, and this results in increases in the delay times and in throughput delays. In consequence, the actual speed at which the application program is run cannot be predicted. In many cases, adaptations are required in the program in order, for example, to make it possible to achieve a minimum speed requirement or synchronization of signals in a PLD. If characteristics other than those available are required while processing logic signals (for example a greater bit length), then they must likewise be cascaded. The linking areas in the PLD thus occupy a larger area than the logic areas. Despite the configurability of the modules, the flexibility for different tasks is thus low. Thus, in general, a different chip with a different chip architecture is chosen for practical problems, whose resources are better matched to the problem (for example bit length, throughput delay requirements).
The architecture concept of the PLDs provides for the programming information to be distributed by the fitter to a large number of identical logic cells on the PLD chip. These are linked by a large number of identical routing areas. The programming information is thus distributed over the area. The configurability of the PLDs is restricted to a small number of configurable parameters, which are permanently set on booting up. In this case, two memories are required: an external boot memory chip (discrete chip, for example an EEPROM 113 in U.S. Pat. No. 4,870,302) and internal memory cells distributed over an area (for example as shown in FIGS. 3a and 10a in U.S. Pat. No. 4,870,302 of FIG. 5 in the publication from Ranmuthu et al. After booting up, the local memory cells contain the information for the links and for the logic functions for the cells. The area and line loss efficiency of the distributed memory cells is approximately two orders of magnitude poorer than that of discrete memory chips of the same performance. However, if less performance is required by the application program than that provided by the chip, then the unused areas likewise unavoidably result in power losses. Typical utilization levels of the resources of PLDs are about 30% to 70%. Only small proportions of them are actively involved in the processing of logic information at any given time.
SUMMARY OF THE INVENTION
The invention is thus based on the problem of avoiding the disadvantages which have been mentioned and of specifying a digital logic unit in which the hardware utilization is improved.
This problem is solved by a reconfigurable digital logic unit comprising two or more logic cells with configurable characteristics, in which case data signals and configuration signals can be processed at the same time; an internal memory with two or more microprograms, containing information relating to the functionality of two or more logic cells, in which case at least one of the microprograms can be reprogrammed as a function of a specific application, at least during operation of the logic unit; means for selection of at least one microprogram; as well as means for configuration of logic cells on the basis of the functionality information of the selected microprogram, at least during operation of the logic unit. The expression “functionality” should be understood as meaning both “data processing” and “data linking”.
The logic unit according to the invention can thus be varied during operation; that is to say the logic cells can be configured during operation of the logic unit, and the microprogram or microprograms can be reprogrammed during operation of the logic unit or while it is being operated. The logic unit can thus be matched to the task placed on it and to be processed at any time while the logic unit is in the operating state, since no fixed configuration and programming is predetermined by the manufacturer; and in fact the unit can effectively be configured in situ, and the characteristics can be changed and adapted in situ. The change to the programming or to the configuration can be predetermined by the programmer in software, or else this may represent an autonomous learning system. Thus, the variation capability that is always provided means that there is no need to provide all the possible commands and links on the chip and, in fact, the required links can be produced based on the particular requirement at any given time, during operation. Considerably less space is therefore required on the chip and the line loss can also be considerably reduced since the adjustment capability means that only those cells and links which are needed for the required application are configured.
In this case, the expression “during operation” should be understood as meaning that state of the logic circuit in which services are offered. In principle, a distinction is drawn between the following modes or operating states of a logic circuit: “switched off” (data is stored, but cannot be changed); “booting up” (changing to the operating state); “during operation” as a characteristic state of the logic unit according to the invention; “ceasing operation” (ending of the operating phase, preparation for the “switched off” state). A further state “not available” (for example=crashed) may be reached from the booting-up process or from the operating state and can be ended again only by ceasing operation. The special case of “hot start” comprises the transition from “ceasing operation” to “booting up”. The aim is thus to ensure that the logic unit according to the invention can be reconfigured at least when it is not in the switched-off mode, the boot-up mode, the cease operation mode and the unavailable mode. In contrast, the configuration of a PLD circuit according to the prior art (see EP 0 253 530 A2) represents only a special booting-up process. The logic unit may, of course, also allow the stated parts to be reconfigured in a known manner during a starting-up mode and/or during a ceasing operation mode.
The expression “logic cell” should be understood as meaning any element which carries out a logic function. In the simplest case, it may be a single memory cell, or in a more complex case it may be a gate, a sub-network comprising two or more gates, or even a processor element. The functional principle of a logic cell corresponds to that of a subroutine, and it may contain a simple functionality (for example “output=input” or “output=constant”), or may be in the form of a sub-network with considerably more complex functionality. Generally, it will contain task elements which are characterized by frequent use (for example primitive logic functions such as gate functions or full-adders) or expedient and advantageous refinements (in particular in the form of a commercial IP).
It is particularly advantageous in this case that, in principle, the configuration process and the data processing can be carried out virtually at the same speed and at the same time. This ensures that the configuration process can always be carried out, that is to say at any time and in any operating state.
The expression “configurable characteristic” that is used should be understood as meaning all non-volatile but variable characteristics or process parameters. Examples of a logic cell include the bit length at the input/the number of variables, the physical position of the inputs, the coding of the bits (for example in series or parallel form), the logic processing of the bits, the time response, the register function, the local memory function, the bit length at the output, the physical position of the output bits or the operational readiness, although this list is not exclusive. The changes can be carried out independently of other processors in the chip, and the bit processing and linking changes are ideally carried out very quickly (in the microsecond or preferably nanosecond range) in each clock cycle.
Those logic cells with configurable characteristics which have a magnetoresistive layer system are particularly suitable. A layer system such as this can advantageously be magnetically adjusted particularly quickly, in particular in a few nanoseconds.
Instead of logic cells with magnetoresistive layers, alternative, similarly powerful technologies may also be used, for example ferroelectric RAMs (FRAM).
Each logic cell in the logic unit according to the invention may have at least one magnetoresistive layer system as well as input and output connections which are connected to connecting interconnects. The layer system may be of the GMR (giant magnetoresistive) type, of the TMR (tunnel magnetoresistive) type, or of the AMR (anisotropy magnetoresistive) type.
The magnetization direction of a magnetic layer may be used for information storage. This storage process is very fast and can be carried out repeatedly with virtually no limit. The resistance of the memory cell is either low or high, depending on the magnetization direction of the free magnetic layer relative to a reference direction. A logic cell based on this may be used as a logic gate, in which case virtually all the normal gate functions (for example NOR, XOR, AND, OR, INV etc.) can be provided by driving or interconnecting two or more cells. The important factor in this case is that the functionality can be changed between at least two of these gate functions by appropriate means. In the same way, a logic cell may be used as a memory and, in particular, the result of a logic operation can be stored. Memory cells of the TRAM (tunnel random access memory) type are particularly suitable, since these can be written to repeatedly without any limit.
According to the invention, links are provided between logic cells to form logic cell blocks in the digital logic unit, having the function of a half-adder, a full-adder or a multiplier. In addition, a logic cell may comprise a local memory which can store intermediate results or final results of a logic operation.
The digital logic unit according to the invention comprises an internal memory with two or more microprograms. This may be a memory which is addressed by command words from a main memory and contains information relating to the functionality and the linking of two or more logic cells. A command word is loaded from the main memory, is analyzed, and the logic cell arrangement required for this purpose is derived from the microprogram. A microprogram such as this is comparable to a command macro and it contains a number of basic operations which can be carried out by linking two or more logic cells. Typically basic operations are loading, analysis or selection. A microprogram may accordingly be regarded as a design plan or circuit, which contains all the required information about the logic cells. In addition, it may also contain information about any memories, registers or similar components which may be required. Furthermore, a microprogram may also contain constants, for example the number “0” may be defined as a constant. In addition, a microprogram can define information about inputs, outputs or about the linking of the inputs to variables and constants.
A large number of standard tasks can be covered by the microprograms; by way of example, a keyboard check can be defined by a microprogram, in the same way as the outputting of data to an external appliance or the inputting and reception of data from an external appliance. In the same way, any desired logic operations can be stored in the form of microprograms, for example arithmetic links such as the basic types of calculation, or else considerably more complex algorithms. Logic operations are broken down into individual components, which are each defined by a microprogram.
The invention particularly advantageously provides for at least one microprogram to be reprogrammable. The microprogram can be loaded, and can be changed as a function of a specific application. This provides particularly high flexibility for the logic unit. It is also possible to provide for a microprogram to have commands for definition of new microprograms or for changing existing microprograms.
According to one development of the idea of the invention, provision is made for a microprogram to comprise commands which are contained in firmware. Furthermore, command sequences in a microprogram can be identified by an application program, and can be stored as a new microprogram. Furthermore, the digital logic unit according to the invention may have a means for selection of at least one microprogram. The microprograms may be defined in advance, or else may be redefined in the sense of “evolvable hardware”. The memory may contain a large number of command words, which each use the means to select at least one microprogram.
The at least one microprogram can be selected by means of a program pointer.
The digital logic unit according to the invention furthermore comprises a means for configuration of logic cells corresponding to the functionality information of the selected microprogram.
The logic cell links which are defined by the selected microprogram as well as the local memory cells which may possibly be required are programmed in reprogrammable hardware. The magnetoresistive logic cells are programmed by a programming routine. The programming routine stipulates the sequence in which the individual logic cells will receive a programming current. The desired logic gate functions are thus programmed. In the same way, links are produced between different logic cells.
The memories which are used for the digital logic unit according to the invention have the advantage that the memory contents are not volatile, that is to say they are retained even after the voltage has been switched off. Nevertheless, logic cells which have already been programmed can be reprogrammed at a later time, that is to say the functionality of a logic cell can be reconfigured. Program loops are thus run through in hardware, that is to say a hardware configuration which is matched exactly for this purpose is created for a specific logic operation and is matched as optimally as possible to the problem to be processed. Voltage need be supplied only to those logic cells which are actually required at that time. When a program loop that is defined by logic cells is finally left, the associated logic cells can be switched off, so that they no longer consume any power. This avoids the problem that occurs with conventional logic units, in that large parts of the hardware are continuously in a waiting state in which they draw current.
It has been found to be particularly advantageous to arrange the logic cells like a raster field. This results in a regularly arranged logic cell layer, in which each individual logic cell can be addressed in the same way as the components of a matrix, by stating the row and the column. It is also possible to provide for different types of logic cells to be distributed regularly on the raster field, for example gates that are required frequently such as NOR, XOR and AND gates may be arranged in all of the areas of the raster field, so that only relatively short distances and fewer functionality configurations need to be bridged when linking individual logic cells. Logic cell links may in principle be formed in any desired way from the raster field. Logic cell links are preferable in which logic cells to be linked are directly adjacent, or are as closely adjacent as possible. The linked logic cells may be arranged on the raster field both in the form of a line or over an area, that is to say in the form of function blocks.
The logic cells with the magnetoresistive layer system and the input and output connections are connected to connecting interconnects which run essentially horizontally and vertically and preferably cross at right angles. The interconnects may be formed from a copper material.
In a further refinement of the idea of the invention, it is possible to provide for logic cells to be arranged in different layers or levels like a grid. Three-dimensionally arranged logic cells allow a considerably wider range of linking options. A variable or constant may also be stored in a logic cell. This logic cell can then be accessed by different microprograms. For example, one of the microprograms may be arranged in a higher layer, and another microprogram may be arranged alongside the logic cell. This logic cell can thus be used by a number of microprograms.
The various layer levels in the logic cells can be connected in a known manner by means of vias which are arranged at right angles to the layer level. Three-dimensional structures such as these are known and therefore require no further explanation. Reconfigurable digital logic units are preferable which contain four to six layer levels of crossing connecting interconnects with magnetoresistive layer systems between them. The individual layers may be separated from one another by an isolation layer. In addition, further components may preferably be provided on an outer face, and can be produced using conventional silicon technology. It is also possible to provide for layers which are adjacent to one another in a surface level preferably to be arranged offset with respect to one another. This makes it possible, for example, to form a straight line connecting interconnect between the second and the fourth layer. The grid arrangement may be Cartesian, or else may be arranged in a “honeycomb”, in the form of a hexagonally very dense packing, in order to form a greater number of closest neighbors.
The invention provides for the processing of logic functions to be controllable by at least one command counter. A command counter, which may also be referred to as a command token, signals which of the logic cells is active at any given time, that is to say the command token points to the logic cell that is working at that time or to the logic link that is working at that time. The command counter may be a logic signal which is set (“1”) in only one logic cell, and is not set (“0”) in all of the other logic cells.
According to a first embodiment variant of the invention, a single command counter is provided for the logic unit. Accordingly, only a single logic cell or a single logic cell link may be active at any given time. The other logic cells are not active during this period. Once the corresponding logic function has been processed, the command counter is “moved on”, that is to say it points to the next logic cell to be processed. The one or more microprograms may be arranged one behind the other on the logic cell array, so that the individual logic cells are processed sequentially.
Alternatively, it is also possible for the logic cells and the logic cell links to be stored randomly on the logic cell array, and this arrangement is comparable to the storage of data on a hard disk.
According to a second refinement, it is possible to provide for a logic unit to have two or more command counters, which may be active at the same time. Two or more microprograms may accordingly run at the same time, that is to say parallel processing takes place. The command counter or the command token may be in the form of a logic signal which is stored in a flag register and is reset after completion of the calculation. A “1” indicates that the logic cell link is active, and the flag is reset to “0” after the calculation. Only one active logic cell arrangement or one active microprogram has the value “1”, which means that the operating voltage is released for the logic cells that are linked to the active microprogram. Joint use of programmed constants and the transfer of results are possible.
Microprograms may be processed in various ways. In the case of synchronously operating logic units, the flag is checked on the next clock cycle, and the next microprogram is then activated. It is possible to provide for the processing in the case of synchronous logic units to be carried out simply under time control, that is to say each microprogram has the same amount of time for processing the programmed command words. In the case of synchronous logic units, it is also possible for the processing to be carried out in a complex form under time control, that is to say with each microprogram being linked to a predetermined time for processing the programmed command words. This time information may, for example, be contained in a variable in the microprogram.
Furthermore, in the case of asynchronously operating logic units, it is possible to provide for the logic release signal to be passed on directly. The time for processing the programmed command words is irrelevant in this case. Measures may possibly be required for synchronization of two or more microprograms which are active at the same time, in order to avoid conflicts such as simultaneous access to one memory cell.
In a development of the invention, it is possible to provide for the logic unit to comprise a table of those logic cells which are occupied and/or those which are not. It is also feasible to use an algorithm to check whether a required logic cell arrangement, for example a multiplier, already exists as a configured block in the logic cell array. In this situation, the same logic cell arrangement could be used by different microprograms. Furthermore, it is possible to provide for an algorithm to find free areas in the logic cells, in order to achieve the optimum utilization of the available logic cells. It is equally possible for the functionality of the logic cells to be checked and, if appropriate, for them to be marked in a table as logic cells that have been classified as being defective.
BRIEF DESCRIPTION OF THE DRAWINGS
Further advantages and details of the invention result from the exemplary embodiment described in the following text and from the drawings. The drawings are schematic illustrations, in which:
FIG. 1 shows a cross section through a logic unit according to the invention, comprising two or more layers of logic cells;
FIG. 2 shows a schematic section view of a logic unit according to the invention with vertical vias; and
FIG. 3 shows a schematic flowchart of the configuration of a digital logic unit according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
The digital logic unit 1 which is illustrated in the form of a section in FIG. 1 comprises two or more layers of magnetoresistive logic cells 2 , each of which has a magnetoresistive layer system with input and output connections which are not shown in FIG. 1 but which are connected to the connecting interconnects 3 , 4 . The interconnects 3 , 4 comprise a large number of parallel interconnects, which are arranged in different levels. The individual interconnects are electrically isolated from one another, and a connection can be made only via those logic cells 2 which are adjacent to both the interconnects 3 and 4 . Each of the memory cells is separated from the adjacent layer by an isolation layer 5 . The logic unit 1 may expediently comprise four to six such individual layers.
The logic cells 2 are non-volatile, but are reprogrammable, being rewritable logic components, which can be programmed at a high speed. They offer the capability to provide a logic function and a memory at the same time, or else to release or to interrupt links.
Further components 7 , which are constructed using conventional silicon technology, are illustrated schematically underneath the lower isolation layer 6 . It is thus possible to combine logic cells 2 with silicon semiconductors.
FIG. 2 shows a schematic section view of a logic unit according to the invention with vertical vias between the individual layers.
The logic unit 1 comprises the layers 8 , 9 , 10 , which are formed analogously to the logic unit shown in FIG. 1 . Vias 12 are formed between the layers 8 , 9 , 10 and a lower layer 11 and produce a vertical connection between the layers, or between logic cells which are arranged on the layers. A grid structure may also be formed in a similar manner, in which the connecting interconnects are formed along all three spatial axes, and a logic cell is located at each intersection of the grid. The X, Y and Z coordinates of a logic cell are required in order to address it.
FIG. 3 shows, schematically, the procedure for the configuration of the digital logic unit.
An internal memory 13 comprises a number of different microprograms 14 , which contain information about the linking of two or more logic cells.
A program pointer 15 selects one of the microprograms in the memory 13 . The selected microprogram 16 contains all the information which is required for programming the logic cells 2 . This is information relating to the processing unit, to the control unit, to the variables, to the input/output processes (I/O) and a command token. There is no need for each microprogram to have information relating to all the items that have been mentioned, and, depending on the objective, individual items may be omitted, or the microprogram may contain further program information.
A programming routine 17 analyzes the information in the selected microprogram 16 , and programs the required logic functions.
A logic cell array 18 comprises a large number of magnetoresistive logic cells 19 which are arranged regularly in rows and columns and are illustrated schematically by raster points in FIG. 3 . The logic cell array 18 may comprise a very large number of logic cells 19 , for example it could contain 1000 times 1000 cells, that is to say a total of 1 million logic cells. In this exemplary embodiment, the logic cell array 18 comprises a single layer. It is also possible to combine two or more such logic cell arrays to form a logic cell grid.
Each individual logic cell 19 can carry out a basic linking process and may, for example, be an AND or XOR gate, or may be configured appropriately.
In order to program the required logic operations and the local memory locations, the programming routine 17 selects those logic cells 19 or groups of logic cells which are not occupied, and are no longer required and can be reprogrammed. This is done using a table 20 , which may also be in the form of a list and contains the free, available logic cells. Alternatively, the occupied logic cells may be recorded, and likewise those logic cells which have been found to be defective. The table 20 may also be in the form of a two-dimensional or three-dimensional matrix and may have an entry for each logic cell 19 , containing information about the current status. The table 20 is updated after each programming process, newly occupied logic cells 19 are identified appropriately in the table 20 , and logic cells 19 which are no longer required are released again. The information in the table 20 is used to determine the area of the logic cell array 18 in which the microprogram 16 that is to be programmed at that time is stored. The information about programmed states and links can be stored in a highly space-saving manner.
FIG. 3 does not show the main memory or its associated peripheral, which contains processing data and command words in a known manner, with the command words selecting the active microprogram from the internal memory 13 .
As can be seen from FIG. 3 , the logic cell array 18 already has a number of programmed logic cell blocks 21 , 22 , 23 , each of which is associated with a specific microprogram in the memory 13 . A contact point 24 is shown schematically between the logic cell blocks 21 and 22 , at which signals or data can be interchanged between the logic cell blocks 21 , 22 . A number of such contact points may, of course, also be arranged between two adjacent logic cell blocks.
In order to program a logic cell, it must first be defined on the basis of its row and column in the selection step 25 . The selected logic cell 26 is then programmed by the programming routine 17 , and this procedure includes the connection of the connecting lines that are required.
The logic cell array 18 contains further logic cell blocks 27 , 28 , which are identified in the table 20 as no longer being required. These may be reconfigured at a later time.
Once all of the logic cells in the logic cell blocks 21 , 22 , 23 have been programmed, the processing of the associated logic cell links can then be started immediately. Two or more logic cell blocks may also be linked to one another in such a way that they form a ring or a loop.
A command token is required for operation of the logic cell blocks 21 , 22 , 23 . This is a logic signal which is produced at an output of the logic cell blocks 21 , 22 , 23 . This is intended to ensure that only one of the logic cell blocks is ever active. The command token is set for the active logic cell block, and the operating voltage is then supplied to this logic cell block. After processing of the microprogram that is associated with this logic cell block, the command token is reset, and the operating voltage is switched off. The command token is passed on to the next logic cell block, so that it can operate.
It is also possible for two or more command tokens to be set at the same time, so that two or more microprograms can be processed at the same time. This mode of operation corresponds to a distributed processor. However, it should be noted that the logic cell blocks which are associated with the respective command tokens operate completely independently of one another, that is to say it is necessary to avoid collisions occurring when access is made to memories or to address or data lines. In a corresponding manner, it is possible to provide for two or more logic cell blocks to operate synchronously. However, asynchronous operation is also possible, provided that precautions are taken to prevent the occurrence of the collisions that have been mentioned. | A digital logic unit can be reconfigured and includes: a plurality of logic cells ( 19, 26 ) that have configurable properties; a memory ( 13 ) with a plurality of microprograms ( 14, 16 ) that contains information on the functionality of a plurality of logic cells ( 19, 26 ), at least one of the microprograms ( 14, 16 ) being reprogrammable depending on a certain application at least during the current operation of the logic unit; elements for selecting at least one microprogram ( 14, 16 ); and elements for configuring logic cells corresponding to the functionality information of the selected microprogram ( 14, 16 ) at least during the current operation of the logic unit. | 8 |
[0001] This a divisional application of U.S. application Ser. No. 11/366,288 filed on Mar. 2, 2006, which is incorporated herein by reference.
[0002] The present invention relates generally to gaskets and particularly to hybrid gaskets constructed of polymers containing inserts for structural support and performance enhancements. More specifically, the present invention relates to a seamless gasket with an internal structural support and a method for making such a gasket.
BACKGROUND OF THE INVENTION
[0003] Gaskets having both polymer (PTFE) and metal components have been known and used for many years. These types of gaskets are acceptable for many gasket applications. Typically, a corrugated metal insert is combined with polymer layers, tapes, or the like to form a gasket able to seal with lower bolt loads, provide improved thermal cycling, and withstand increased pressure resistance.
[0004] Conventional prior art gaskets will often have polymer rings sandwiched around a corrugated metal insert. The rings are attached to the insert and/or to each other by some form of adhesive. This sandwich-type construction has historically meant that the gasket has seams at the inside diameter (ID) and/or outside diameter (OD) of the gasket. All of the layers of the gasket, including the metal and adhesive layers, are exposed at the inside diameter and outside diameter of the gasket. Problems with these types of gaskets include corrosion or degradation of the various components of the gasket that may occur as a result of the exposure of the metal and/or adhesive to the process temperature and media in the system in which the gasket is used. Many industries including semiconductor, food and beverage, pharmaceutical and specialty chemicals cannot tolerate the potential for process contamination that exists with the metal and/or the adhesive being in contact with their process media. In applications above the softening or melt point of an adhesive (˜200° F.) a typical failure mode or limitation is that the adhesive is corroded away, and the gasket seal may fail or require re-torquing as a result of the reduced bulk of the gasket. These higher temperatures may also result in blow-out failures when the adhesive is melted or softened.
[0005] If an insert is exposed, or is eventually exposed, to the environment, media, or other conditions in the system that the gasket is placed, prior art gasket construction requires the use of metal inserts that are chemically compatible with the process being sealed. For many corrosive chemical applications where the tightness, pressure resistance and resiliency of this type of gasket is required, exotic alloy inserts such as hastalloy, titanium, and other similar products are required. The resulting gaskets are very expensive and the required adhesive layers will still suffer from the same thermal degradation or chemical corrosion as described above. Both of these limitations may limit or prevent the use of the gasket design and the resultant performance benefits. Also, while exotic alloy inserts may allow the use of these gaskets in harsh chemical applications, there is no means of making this design suitable for use in applications like semiconductors, food and beverage, or specialty chemicals where contamination from the adhesive is the limiting factor.
[0006] FIG. 1 illustrates one prior art gasket that was developed to minimize the limitations of the earlier style corrugated insert gasket stated above. In this construction methodology, the gasket includes a single polymer ring that has a slit in it that extends around the outside diameter from the outside diameter toward the inside diameter. The slit does not extend all the way through the polymer ring to the inside diameter. A metal insert is positioned in the pocket that is formed by the slit of the polymer ring. The metal insert may or may not have an outside diameter essentially the same as the polymer ring. This gasket design effectively isolates the corrugated insert at the ID from the process media thus eliminating one of the limitations with the original gasket design. Whether or not the metal insert is directly exposed to the outside diameter of the gasket, the general conditions in a plant or a system where the gasket is used may still attack or thermally degrade the adhesive and/or the metal insert via the slit in the outside diameter of the gasket. Additionally, application for this improved gasket in PTFE lined piping systems can be negated because of static electricity discharge between the exposed metallic OD of this gasket construction to the bolts that secure the flange together. Also, because glue or some form of adhesive is still required with this design, the gasket's use within piping systems or vessels where any type of contamination is undesired is still restricted. The manufacturing technology and throughput with this pocket style gasket stated above is very expensive, very labor intensive, and stringent quality control measures must be employed to insure that the slit never extends all the way to the ID. If this were to happen and go unchecked, this gasket could fail catastrophically in chemical services that are not compatible with the insert metallurgy.
[0007] Accordingly, despite the advancements made with the ID protection envelope detailed above, there remains a need for a completely seamless metallic or corrugated metallic insert gasket that does not contain any seams at the ID or OD and a cost effective method to create such a gasket which does not rely upon careful slitting of the envelope material that is placed around the insert. A seamless corrugated/metallic insert gasket would ideally prohibit or lessen the ability of a corrosive agent to attack or degrade any structure of the gasket. A seamless corrugated/metallic insert gasket and a method for making the same, in accordance with the present invention, would effectively address one or more of the foregoing or other drawbacks associated with prior art gaskets.
[0008] Another prior art PTFE gasket is the “Task-Line” type gasket where a perforated stainless steel (SS) insert is encapsulated within a full density (hard) PTFE matrix. This gasket is made using molds whereby PTFE resin is charged into the mold, the insert is then added, and more PTFE resin is added on top of that. The PTFE resin and insert are compressed under extreme pressure at elevated temperatures above the PTFE melt point temperature. The PTFE resin therefore forms a hard, solid mass encapsulating the insert. The finished gasket is very hard (the PTFE is at full density, about 2.2 gm/cc), there are virtually no recovery/resiliency advantages with this design, and creep of the virgin PTFE remains very problematic.
[0009] Accordingly, there is a need for a finished gasket with any desired PTFE “skin” density between an expanded PTFE density (typically about 0.6 gm/cc) and the theoretical “full density” of PTFE (about 2.2 gm/cc). In the prior art Task-Line gasket above, the PTFE resin is melted above the PTFE sintering temperature and flows/compacts together around the insert. There is needed the beneficial physical properties of the lower density expanded, porous or microcellular PTFE. An approximate 0.6 gm/cc density PTFE “skin” or facings around the insert are desirable for flange surface adaptability (conformability) and low stress to seal, while higher “skin” densities are desirable when the flange surfaces do not require a highly compressible facing material or cut-through resistance at higher stresses. The use of various expanded, porous, or microcellular PTFE components allows the final gasket to have much improved creep resistance over the Task-Line (virgin, hard) PTFE gasket. Also, improved gasket resiliency/springback is a major performance advantage of any corrugated insert PTFE gasket with soft PTFE facings. The hard PTFE skin of the Task-Line gasket negates any benefit of a corrugated insert, and thus there are no known commercial Task-Line products with a corrugated insert.
SUMMARY
[0010] In accordance with the present invention, there is provided a seamless corrugated/metallic insert gasket and a method of making the same. The gasket includes a structural insert fully surrounded by at least one polymer, such as polytetrafluoroethylene (‘PTFE’). In one preferred embodiment, the insert is a corrugated metal ring.
[0011] Gaskets are often formed from non-reactive polymers. PTFE is a common gasket polymer that is a generally non-reactive, high purity, durable material. For instance, PTFE gasket materials can be compressed between two surfaces and provide, initially, an effective seal at ambient temperature and moderate bolt load. However, PTFE can be damaged in high bolt-load assemblies (i.e., the gasket is exposed to very high compression). Additionally, the creep or flow properties of PTFE are exacerbated at temperatures above ambient, and all PTFE based gaskets exhibit very low springback or recovery. Therefore, one proven PTFE gasket technology that offers improved pressure resistance, recovery and creep performance will typically include some internal structural support or insert. Expanded PTFE sheet materials are naturally very “floppy”, and inserts are used with this material to also impart greater gasket rigidity. Gasket manufactures have attempted to introduce these inserts into the gaskets in a number of ways.
[0012] PTFE can have an elongated form, like a tape, that is successively wrapped around an insert in an offset pattern until the entire insert is covered by the PTFE tape. In another very common construction, the PTFE includes two layers of PTFE bonded together by an adhesive wherein the insert is placed between the layers. This sandwich construction is prone to the adhesive being degraded at both inner diameter (“ID”) and outer diameter (“OD” seams. Polymer rings can also be slit along their outside diameter to allow a support to be inserted between the upper and lower surfaces of the ring (See FIG. 1 ). Overall, in these and other prior art approaches, seams are created that allow process fluid to seep between and attack the metallic inserts and the gaskets cannot be manufactured with high consistency or in a high volume, automated fashion. In the present invention, an expanded, porous, or micro-cellular polymer fully encases an insert in a seamless fashion. In practice, the seamless hybrid gasket comprises first and second annular rings comprising a polymer. In one preferred embodiment, the polymer is PTFE or expanded PTFE. The polymer, in other preferred embodiments, is envisioned as porous PTFE, filled PTFE, or microcellular PTFE. Other polymer choices are available. It is foreseen that the two polymer layers may not be the same exact polymer.
[0013] The rings, or some other geometric shape, have inner and outer peripheries or diameters. In the case of rings, there are an ID and an OD, wherein the width of the first and second rings is the radial distance from the inside diameter to the outside diameter. The gasket also includes an insert, which in one preferred embodiment is a corrugated metal ring, having an ID greater than the ID of the first and second rings and an OD less than the OD of the first and second rings. The insert can be any metal, but is preferably selected from the group consisting of stainless steel, carbon steel, copper alloy, nickel alloy, titanium alloy and hastalloy. The insert is sandwiched between the first and second rings without using any adhesive. The first and second rings are then unified around the insert so that the gasket has a seamless ID and OD.
[0014] The two or more PTFE layers are unified under the application of heat and pressure. The process of unifying the layers, as opposed to the old techniques, creates a seamless gasket that includes the structural benefits of having an internal rigid support, without any of the drawbacks of the prior art technologies (adhesive volume loss, adhesive contamination, OD metal exposure, ID metal exposure, slit location and depth, etc. Additionally, this process is much more capable of high volume, automated manufacturing than any of the current technologies. The ability to provide a seamless inside diameter and outside diameter of a hybrid gasket comprised of a unitary polymer construction around an insert is a new gasket construction, and a new method of gasket construction.
[0015] The method of unifying the polymer layers is another aspect of the present invention. In use, the method includes providing at least two sheets, each comprising a polymer material. An insert, generally an annular ring, comprised of a corrugated metal is placed between the two sheets. The plurality of sheets are unified around the annular ring, and the resulting sheet is cut into the desired gasket shape. The inside diameter of the sheet is less than the inside diameter of the annular ring, and the outside diameter of the sheet is greater than the outside diameter of the annular ring. The method of forming a seamless hybrid gasket by unifying the sheets comprises heating the polymer sheets, applying pressure, and/or applying heat and pressure simultaneously through the use of, for instance, a heated platen press with a PLC (Programmable Logic Controller) to control the platen temperature and rate of heat up and cool-down, and an air-actuated cylinder to apply and maintain the required compressive load during the heating process. The result is a unitary polymer construction of low density expanded, porous or microcellular PTFE with a corrugated metal insert embedded therein. No adhesive is necessary, or alternatively, no adhesive is applied such that the resulting gasket has no adhesive exposed to the inside and outside diameters of the gasket.
[0016] The seamless hybrid gasket of the present invention effectively addresses one or more of the problems associated with prior art gaskets. For instance, the gasket of the present invention precludes the possibility of a corrosive agent corroding the glue layers between the different layers of PTFE that are typically found sandwiched about an internal gasket insert. The foregoing and additional features and advantages of the present invention will become apparent to those of skill in the art from the following detailed description of a preferred embodiment taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a perspective view of a prior art gasket with an inner diameter (‘ID’) seam and an outer diameter (‘OD’) seam;
[0018] FIG. 2 is a perspective view of a seamless hybrid gasket in accordance with the present invention;
[0019] FIG. 3 is a side, cut-away view illustrating the construction of the gasket in accordance with the present invention;
[0020] FIG. 4A is a perspective view of the components of the present invention in a spaced relationship in order to illustrate the method of forming a hybrid gasket in accordance with the present invention; and
[0021] FIG. 4B is a top-down view of the gasket of the present invention.
[0022] FIG. 5 is a side, perspective, crossectional view of an alternative method of forming a hybrid gasket in accordance with the present invention.
[0023] FIG. 6 is a side, perspective, crossectional view of an alternative construction of a gasket of the present invention.
DETAILED DESCRIPTION
[0024] FIGS. 2 through 4B illustrate one or more preferred embodiments of the present invention. Naturally, a person having ordinary skill with the assembly and construction of gaskets will be able to create a gasket that incorporates the teachings of the present invention, but which may look different and incorporate different, alternative parts.
[0025] Turning first to FIG. 1 , there is illustrated a prior art embodiment of a conventional gasket 2 comprised of a polymer ring 4 and an insert (not visible). An individual, solid polymer ring must first be formed into an envelope so it is partially separated about a slit 6 that extends around the entirety of the outer diameter 8 . The slit 6 creates an upper portion and a lower portion, but the slit does not extend fully to the inner diameter. Therefore, there is effectively a pocket created in ring 4 along the outer diameter 8 of gasket 2 . This slit 6 must be carefully formed such that the two portions of the envelope are approximately the same thickness (the slit should occur halfway through the original polymer ring thickness), and the depth of the slit must be carefully controlled such that it does not extend too close to or through the ID 7 of the polymer ring.
[0026] The insert is positioned within the pocket. (During this positioning step, the slip envelope is also prone to tearing.) The insert will generally have an OD equal to or less than the OD of ring 4 . Here, it should be apparent that the insert's OD is less than the OD of the ring because the insert is not visible. An adhesive is applied to the overlapping portions of the ring, the insert, or both. This pocket-type construction means that all of the layers of the gasket, including the insert and adhesive layers, are exposed at the OD) seam. This creates durability, contamination and safety issues, as discussed above. Basically, corrosion or degradation of the various components of the gasket may occur as a result of the exposure of the insert and/or adhesive to the environment and media around a given system in which the gasket 2 is used. For instance, most currently used adhesives soften, flow and ultimately decompose when exposed to temperatures above 200 F, and because of the loss of bulk within the gasket, the bolts loosen and require re-tightening (exactly the failure mode that the gasket design attempts to overcome). The flow, degradation and ultimate disappearance of the adhesive layers pose a contamination issue (pharmaceutical, specialty chemical, food and beverage, and semi-conductor facilities will not use this type gasket because of process contamination) and a corrosion issue (many of the adhesives used contain chlorides which will attack stainless steel under certain conditions, and several companies again will not use this gasket technology because of corrosion concerns with their piping and equipment).
[0027] Referring now to FIG. 2 , a seamless hybrid gasket 10 in accordance with the present invention is illustrated. Gasket 10 comprises a unitary polymer construction 12 . In one preferred embodiment, the polymer is PTFE or expanded PTFE. The polymer, in other preferred embodiments, is envisioned as porous PTFE, filled PTFE, microcellular PTFE, and the like. Other types of polymers may be selected, including other expandable or filled polymers that may compress. It is also foreseen that the polymer construction may be a mixture or combination of two or more polymers. Here, gasket 10 is illustrated as a conventional circular shape with an ID 14 and an OD 16 . Other shapes are available.
[0028] As best seen in FIGS. 3 and 4A , the gasket 10 also includes an insert 20 , which, in one preferred embodiment, is a corrugated metal ring having an insert ID 22 greater than the ID 14 of polymer 12 and an insert OD 24 less than the OD 16 of polymer 12 . Insert 20 can be any metal, but is preferably selected from the group consisting of stainless steel, carbon steel, copper alloy, nickel alloy, titanium alloy and hastalloy. Insert 20 is fully embedded in the polymer 12 . FIG. 3 provides a cross-section view of gasket 10 illustrating the corrugated structure of insert 20 .
[0029] The polymer 12 can be formed of expanded PTFE having a predetermined density. One conventional way to form sheets of expanded PTFE is to wrap thin PTFE membranes on a mandrel to a predetermined thickness. The PTFE membranes are then heated to unify the membrane layers into a unitary PTFE construction. Typically, commercial expanded PTFE sheets can have a density ranging from about 0.5 gm/cc to about 1.1 gm/cc. Through careful process controls of heat, pressure and time of heat and pressure, the present gasket can be engineered to have any specific or predetermined density within the range of about 0.2 to 2.2 gm/cc, preferably about 0.5 to 2.0 gm/cc.
[0030] In more detail, and as illustrated in FIG. 4A , seamless hybrid gasket 10 is formed from at least two initial sheets of polymer 30 , 30 ′ that are then unified to form a unitary polymer construction 12 , completely encapsulating the insert 20 . The polymer sheets can be any shape that covers insert 20 in a manner to allow contact between the sheets 30 , 30 ′ along portions of the polymer inside the entirety of insert ID 22 and outside the insert OD 24 . Heat and pressure can then be applied to one or both sheets 30 , 30 ′ to unify them.
[0031] In one example, sheets 30 , 30 ′ are pressed together at about 650 F degrees and two-three pounds per square inch (‘psi’) of contact stress. Sections of expanded PTFE sheet are placed around a stainless steel insert that is smaller than the squares. The components are transferred to heat press platens 35 . The air pressure in the compression cylinder applying load to the platens is adjusted to the pressure necessary to develop two-three psi stress across the square sections of expanded PTFE, and the top and bottom platens are brought together around the components. A programmable logic controller is configured to ramp up the heat of the platens to 650 F at a rate of approximately 10 degrees per minute. Once at temperature (650 F), the components are held at this temperature, under the two-three psi stress, for a minimum of 5 minutes. After 5 minutes, the platen heaters turn off and the entire fixture is cooled to about 210 F degrees, while under load. At 210 F or lower the platens are released and the unified PTFE/metal components are released from the platens.
[0032] The density of the polymer is one factor in determining the correct processing conditions. The density of the PTFE in the completed gasket may be determined prior to manufacturing. The starting density of the PTFE material, the platen temperature and the compressive stress applied to the components during the heating and cooling process, all will impact the resultant density of the PTFE of the finished gasket. In the foregoing example, the polymer sheets were heated to 650 F degrees. The heating range will vary depending on specific polymer used. When heating PTFE, an exemplary heating range includes from about 600 to 675 F degrees.
[0033] The result of the fusing process, as seen in FIG. 4B , is a sheet 40 to be sectioned into gasket 10 . In this illustrated embodiment, a circular insert and a circular-shaped gasket are desired. Therefore, sheet 40 is cut, punched, or the like to create the gasket OD 16 and inner ID 14 . From this view, the insert ID 22 and insert OD 24 are also shown in broken lines.
[0034] The method produces seamless hybrid gasket 10 . Insert 20 is fully insulated from the environment and media that will contact gasket 10 . The absence of any seams precludes the possibility of a seam adhesive degrading over time. The result is an improved gasket applicable for a wide range of applications.
[0035] Turning now to FIG. 5 , there is shown an alternative embodiment of a gasket 50 made up of a polymer ring 52 formed around a metal insert 54 . The polymer ring 52 component of the gasket 50 defines an inside diameter 60 and outside diameter 62 . The metal insert 54 defines an insert inside diameter 56 and an insert outside diameter 58 . In this alternative embodiment, the polymer 52 is compressed along the inside portion 65 and outside portion 67 of the polymer ring 52 , or alternatively at greater heat and/or pressure at the inside and outside portions. In other words, in the example shown in FIGS. 4A and 4B , the entire gasket was subject to heat and pressure to unify the two or more polymer sheets around a metal insert. In the example of FIG. 5 , heat and pressure, shown in arrows are applied only around the inside portion 65 and outside portion 67 of the polymer ring 52 . In this way, the portion of the ring 52 that is generally adjacent to the metal insert 54 is not heated or compressed. The characteristics of the polymer that make up the polymer ring 52 would be relatively unchanged in the area of the gasket 50 that is adjacent and above and below the metal insert 54 . The polymer rings that form the polymer section 52 are only unified inside of the inside diameter of the metal insert and/or outside the outside diameter of the metal insert. In this alternative embodiment, the inside portion 65 and outside portion 67 of the gasket 50 can be subjected to extreme heat and pressure to very securely lock or embed the metal insert 54 within the polymer ring 52 . In this example also, the polymer sheets that make up the polymer ring 52 may be in the shape of separate rings. In other words, the formative polymer sheets may have the same inside diameter and outside diameter as those of the formed gasket, so no subsequent trimming step would be necessary.
[0036] In a variation of this example in FIG. 5 , the inside and outside portions 65 and 67 may be subject to sufficient heat and pressure so that the unified portions are relatively rigid to improve installability of the gasket. In practice, the inside and outside portions 65 and 67 would have a pinched appearance that is a result of densifying the select portions of the gasket relative to the rest of the gasket.
[0037] FIG. 6 is a still further alternative embodiment of the gasket 70 . In this alternative, the gasket 70 is comprised of an inner, annular polymer component 72 outer, annular polymer component 74 and parallel but sandwiched components 76 . In one example, the portion 76 is comprised of flexible graphite material. The polymer components 72 and 74 are unified around the metal insert 80 .
[0038] While the invention has been described with reference to specific embodiments thereof, it will be understood that numerous variations, modifications and additional embodiments are possible, and all such variations, modifications, and embodiments are to be regarded as being within the spirit and scope of the invention. | The invention relates to a seamless hybrid gasket and the method of making the same. The gasket includes a unitary polymer construction and an insert for enhanced pressure resistance, reduced stress to seal, improved thermal cycling performance and structural support. | 5 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a mobile communications terminal which is designed to transmit speech signals and to receive and reproduce speech signals, and which has a speech-reproduction device.
[0002] In mobile communications terminals of this type, speech reproduction or audio reproduction is carried out almost exclusively with the aid of very small, dynamic sound transducers which are attached directly behind a front panel of the communications terminal. Due to the ever-shrinking dimensions of the housings of communications terminals, and as a result of the interest in increasingly large display panels, only very limited space is available on the front of the device for the speech-reproduction device. This causes a miniaturization of the speech-reproduction device, resulting in a reduction in the efficiency and a deterioration in the sound quality of the speech-reproduction device used in the mobile communications terminal.
[0003] On this basis, an object of the present invention is to improve the speech quality of a mobile communications terminal.
SUMMARY OF THE INVENTION
[0004] This object is solved in the aforementioned mobile communications terminal in that the speech-reproduction device has a sound transducer which is disposed inside a housing of the mobile communications terminal, and that at least one sound transmission opening is provided in the housing to forward the sound produced by the sound transducer to the outside of the mobile communications terminal.
[0005] Due to the selected arrangement of the sound transducer, account is advantageously taken of the fact that the space normally occupied (according to the state of the art) on the front of a mobile communications terminal by a speech-reproduction device, such as a loudspeaker, can be made available to other components, such as an enlarged display. The sound generated inside the housing is forwarded to the outside via the at least one sound transmission opening whereby, for example, sound transmission openings distributed over the front of the housing can be provided.
[0006] The sound transducer is preferably designed as a flat loudspeaker with a diaphragm and actuation parts for the diaphragm. The use of a flat loudspeaker offers the advantage that it can extend over large areas inside the housing of a mobile communications terminal, so that a large effective area is available for sound radiation. Further advantages of the use of a flat loudspeaker are that it has a particularly low structural height, which is desirable for space-saving reasons, and the excursions of the diaphragm have no significant effect on the total required housing volume of the mobile communications terminal.
[0007] The sound transducer, such as the flat loudspeaker or a dynamic sound transducer, is preferably fitted to the inside wall of the housing. In the case of a flat loudspeaker, its diaphragm extends, for example, substantially over the entire cross section of the mobile communications terminal.
[0008] Alternatively, the sound transducer also can be integrated into a circuit board of the mobile communications terminal. If the sound transducer is designed as a flat loudspeaker, the area of the circuit board behind the display, for example, can be used to dispose the flat loudspeaker. A combination of the flat loudspeaker with a keypad contact area of the mobile communications terminal is also possible.
[0009] In design forms in which the sound transducer is designed as a flat loudspeaker, the diaphragm is formed, for example, by a plastic film or plate, whereby the actuation parts for the diaphragm may be piezo-ceramic actuators or dynamic actuators, with which the diaphragm is provided. The diaphragm dimensions in flat loudspeakers exceed those of known dynamic sound transducers by orders of magnitude, so that they are favorable for increased sound pressure. Increased sound pressure is particularly desirable if hands-free operation of the mobile communications terminal is also required. The arrangement of the flat loudspeaker inside the housing and the radiation of the sound through a number of distributed sound transmission openings ensures that, if hands-free mode is mistakenly activated, damage to the hearing is avoided, which may occur in known combinations of sound transducers with large diaphragm excursions and very small sound openings.
[0010] The sound transducer provided inside the housing may be combined with at least one further sound transducer, such as a sound transducer which is normally disposed behind the front panel of a mobile communications terminal. In this case, the effective acoustic radiation area of the speech-reproduction device of the mobile communications terminal is increased without the need for a similar increase in the housing volume. This significantly improves the sound of the speech-reproduction device, particularly in terms of bass reproduction.
[0011] The sound transducer also may be combined with the further sound transducer to form a two-way system. In particular, the further sound transducer can be designed as a display loudspeaker, whereby the display surface or the display protection window is used for sound radiation. Display loudspeakers of this type are well suited to the reproduction of a sound frequency range above 1 kHz. It is, therefore, preferable if the sound transducer disposed inside the housing is designed to radiate sound at a frequency lower than 1 kHz, and if the further sound transducer, such as the display loudspeaker, is designed to radiate sound at a frequency higher than 1 kHz. It must be emphasized that the sound transducer disposed inside the housing may, for example, be a flat loudspeaker, as explained above, or a dynamic sound transducer. The two-way system implemented in this way enables high-quality reproduction of a broad frequency range for the sound.
[0012] Additional features and advantages of the present invention are described in, and will be apparent from, the following Detailed Description of the Invention and the Figures.
BRIEF DESCRIPTION OF THE FIGURES
[0013] [0013]FIG. 1 shows a longitudinal section of a mobile communications device with a flat loudspeaker disposed inside the housing.
[0014] [0014]FIG. 2 shows a longitudinal section of a mobile communications device with dynamic sound transducers disposed inside the housing, combined with a display loudspeaker.
[0015] [0015]FIG. 3 shows a longitudinal section of a mobile communications terminal with a flat loudspeaker disposed inside the housing and integrated into a circuit board.
[0016] [0016]FIG. 4 shows a longitudinal section of a mobile communications terminal with a flat loudspeaker disposed inside the housing and assigned to a keypad.
DETAILED DESCRIPTION OF THE INVENTION
[0017] As shown in FIG. 1, an example of a mobile telephone has a display cover 1 , to protect an underlying display panel 9 and a keypad 2 , on an upper casing 3 of a housing of the mobile telephone.
[0018] A lower casing 4 of the mobile telephone which, together with the upper casing 3 , forms the housing of the mobile telephone, is fitted with a sound transducer in the form of a flat loudspeaker 5 , which reproduces speech signals received by the mobile telephone. The flat loudspeaker 5 is fitted via piezo-ceramic or dynamic actuators on the lower casing 4 and substantially extends over the entire length of the mobile telephone. The flat loudspeaker 5 is formed from a plastic film.
[0019] The flat loudspeaker 5 , seen from the display cover 1 , is disposed behind a circuit board 7 of the mobile telephone. Since the circuit board 7 normally leaves a substantial part of the longitudinal section of the mobile telephone free, the sound generated by the flat loudspeaker 5 may pass by the circuit board.
[0020] For sound emission, the upper casing 3 of the mobile telephone has a number of transmission openings 6 , which may be disposed around the display panel 1 .
[0021] The flat loudspeaker 5 may use a large part of the housing height/width and, therefore, may have a particularly large radiation area for sound waves or, in the vicinity of peripheral suspensions of the circuit board 7 on the inside of the housing of the mobile telephone, the radiated sound reaches the transmission openings 6 .
[0022] [0022]FIG. 2 shows an alternative design form of the present invention, in which the display cover 1 is designed as a display loudspeaker. In this design form, the lower casing 4 is equipped with two dynamic sound transducers 8 , which are disposed directly on the inside of the lower casing 4 . The dynamic sound transducers 8 are particularly suitable for the reproduction of low frequencies; for example, in the range below 1 kHz. It is emphasized that, as alternatives to one another, either a small number of large, or a comparatively large number of small, dynamic sound transducers may be provided inside the housing.
[0023] The sound radiated by the dynamic sound transducers 8 reaches transmission openings 6 in the upper casing 3 of the mobile telephone. In the design form according to FIG. 4, the transmission openings 6 are also disposed around the display cover 1 , which is designed as a display loudspeaker in this design form. The display cover 1 is used to reproduce the frequency range above 1 kHz, resulting in sound radiation via two paths, of which the dynamic sound transducers on the lower casing 4 use the lower frequency range and the display panel 1 , as a display loudspeaker, uses the high frequency range.
[0024] The sound radiated by the dynamic sound transducers 8 can pass in the direction of the transmission openings 6 through recesses in the circuit board 7 or in the vicinity of peripheral suspensions of the circuit board 7 covering sides of the mobile telephone housing.
[0025] In terms of the design form of a mobile telephone equipped with a number of sound transducers illustrated in FIG. 2, it must be emphasized that the dynamic sound transducers 8 shown in FIG. 2 can be replaced simply by a flat loudspeaker having a plastic film or plate, as explained above in connection with FIG. 1.
[0026] [0026]FIG. 3 shows an alternative design form for an arrangement of the flat loudspeaker 5 inside the housing of the mobile telephone. Here, the flat loudspeaker 5 is integrated into the circuit board 7 of the mobile telephone, in the present embodiment behind the display panel 9 . The display panel 9 is raised via contacts above the circuit board 7 and, therefore, offers the flat loudspeaker 5 the option of connecting to the air volume in the upper casing 3 of the mobile telephone housing as well as to the transmission openings 6 on the front of the housing.
[0027] A further design form for the arrangement of the flat loudspeaker 5 inside the housing of a mobile telephone is shown in FIG. 4. The design form shown relates to a mobile telephone in which the keypad units are accommodated on a separate keypad circuit board. The flat loudspeaker 5 forms this keypad circuit board, whereby contacts 10 , which can be activated by push-buttons 11 disposed in front thereof, are fitted on the upper side of the flat loudspeaker 5 . In the design form shown in FIG. 4, it must be noted that the sound amplitude of the flat loudspeaker 5 must be selected as small compared to the actuation path for a contact.
[0028] It must be emphasized that, in the design forms of a mobile telephone according to FIGS. 3 and 4, a combination is also possible with the display cover 1 according to FIG. 2, which is designed as a display loudspeaker. With such modifications, the flat loudspeaker 5 would itself in each case support the display loudspeaker in the low-frequency range.
[0029] Although the present invention has been described with reference to specific embodiments, those of skill in the art will recognize that changes may be made thereto without departing from the spirit and scope of the present invention as set forth in the hereafter appended claims. | A mobile communications terminal is provided which is designed to transmit speech signals and to receive and reproduce speech signals, and which has a speech-reproduction device, wherein improved speech quality is achieved in that the speech-reproduction device has a sound transducer, which is disposed inside a housing of the mobile communications terminal, and at least one sound transmission opening provided in the housing, which forwards the sound generated by the sound transducer to the outside of the mobile communications terminal. | 7 |
FIELD OF INVENTION
The present disclosure relates to swimming pools, and, more particularly, to a universal shift apparatus and method for a swimming pool cover assembly.
BACKGROUND
Swimming pool covers are often used for keeping the water free of trash, to shield the water from sunlight that could degrade protective chemicals in the water and for other purposes. Automatic pool covers are often preferable over manually-operated covers, because the cover can be easily extended when the pool is not in use and retracted during use. In most cases, a pool cover box is located at one end of the pool to hold the pool cover system.
Referring to FIG. 1A , an abstract view of a typical pool cover system 10 is shown. System 10 includes a motor 12 , a drive shaft 14 extending from motor 12 , a wind-up reel 16 for collecting a rope 18 , a gear box 20 , a swimming pool cover 22 and a roll-up tube 24 on which to wind the cover 22 . Rope 18 extends to a remote pulley system (not shown) and then back to a leading edge of the cover 22 . Reel 16 and a roll-up tube 24 are usually mounted in a free-wheeling fashion on drive shaft 14 to turn independently therefrom. Gear box 20 includes mechanisms to engage either the reel 16 or the roll-up tube 24 , depending on whether the cover 22 is to be extended or retracted.
By turning drive shaft 14 in direction A, clockwise relative to motor 12 as shown, shaft 14 engages the gear mechanism in gear box 20 to drive reel 16 in direction A. This action winds rope 18 on reel 16 , thereby causing cover 12 to be extended outward over the pool (not shown). Alternately, by rotating drive shaft 14 in direction B, counter-clockwise relative to motor 12 , roll-up tube 24 is engaged by drive shaft 14 via the mechanism in gear box 40 , so that the pool cover 22 is retracted on tube 24 and removed from above the pool. The pool cover system 10 shown in FIG. 1A is referred to as a right-hand system, since the pool cover motor is located on the right side in the pool cover box (not shown).
Sometimes the layout of the pool and its surroundings dictate that the pool cover motor be located on the left-hand side of the pool cover box, as shown in FIG. 1B . The pool cover system 30 shown in FIG. 1B is referred to as a left-hand system, since the pool cover motor 32 is situated on the left side of the pool cover box. As in FIG. 1A , the drive shaft 34 , reel 36 , rope 38 , cover 42 and roll-up tube 44 are substantially identical to the corresponding elements shown in FIG. 1A . The main distinction is that different mechanisms are needed in gear box 40 , compared to the mechanisms in gear box 20 , in order for reel 36 and roll-up tube 44 to be engaged to rotate in directions opposite to the directions of rotation in the right-hand pool cover system shown in FIG. 1A .
Accordingly, in FIG. 1B , if the drive shaft 34 rotates in a direction C, counter-clockwise to motor 32 , this action turns reel 16 in direction C to collect the rope 38 on reel 36 . Alternately, if drive shaft 34 rotates in a direction D, clockwise to motor 32 , then cover 42 is retracted onto roll-up tube 44 .
FIG. 2A shows a gear box 20 having a prior art gear mechanism 50 for the right-hand system in FIG. 1A . A single dog gear 52 is fixedly mounted to roll-up tube 24 (shown in FIG. 1A ). Another single dog gear 54 is fixedly mounted to reel 16 (shown in FIG. 1A ). A double dog gear 56 is rotatably mounted on drive shaft 14 to be free-wheeling along shaft 14 . A shear pin 57 is secured into drive shaft 14 to extend orthogonally outward from the drive shaft 14 . The shear pin 57 extends into a slanted slot 58 formed in double dog gear 56 .
Accordingly, as drive shaft 14 is rotated in direction A, double dog gear 56 is moved along drive shaft 14 in the direction E, so that double dog gear 56 couples single dog gear 54 to drive reel 16 and collect rope 18 , shown in FIG. 1A . Alternately, as drive shaft 14 is rotated in direct B, double dog gear 56 is moved along drive shaft 14 in the direction F, engaging single dog gear 52 . This action drives the roll-up tube 24 and collects the pool cover 22 , shown in FIG. 1A .
Similarly, FIG. 2B shows gear box 40 having a prior art gear mechanism 60 that drives the left-hand system shown in FIG. 1B . A single dog gear 62 engages roll-up tube 44 , and a single dog gear 64 engages reel 36 . A double dog gear 66 is mounted to free-wheel on drive shaft 34 . When drive shaft 34 rotates in direction C, double dog gear 66 is forced by shear pin 67 along shaft 34 in direction H. This engages the reel 36 to collect the rope 38 , shown in FIG. 1B . When drive shaft 14 rotates in direction D, double dog gear 66 is forced by shear pin 67 along shaft 34 in direction G. This engages the roll-up tube 44 to retract cover 42 , as shown in FIG. 2B .
Accordingly, prior art systems involve a swimming pool builder using both right-hand and left-hand motor systems, including different gear boxes, in order to work with various pool layouts and the requirements of customers. Consequently, both right-hand and left-hand types of motor systems must be readily supplied by a pool equipment supplier, adding to the supplier's inventory demands. Moreover, it is difficult to forecast which type of system will be in greater demand, resulting in over-supply and under-supply of right and left-hand motor systems. Furthermore, complex prior art gear boxes, such as shown in FIGS. 2A and 2B , are relatively expensive and are maintenance-intensive.
A pool cover motor system may also be equipped with a torque limiter separately mounted, so that, in the event the cover or one of its components becomes jammed or stuck, the motor or other parts of the pool cover motor system will not be damaged. Typically, torque limiter apparatus includes some type of device that slips relative to the rotatable shaft in the event that a predetermined torque limit on the device is exceeded. However, adding a torque limiter to the motor system also adds extra cost to the manufacture of the motor system.
SUMMARY
In one exemplary implementation, a universal shift apparatus and method for a swimming pool cover motor has a rotatable drive shaft and a rope attached to the end of the swimming pool cover. A reel element collects the rope, and a roll-up element collects the swimming pool cover. A gear drive assembly on the rotatable drive shaft drives the reel element in a first rotational direction as the shaft rotates in a first direction and drives the roll-up element in a second rotational direction as the shaft rotates in a second direction. A shift assembly is associated with the gear drive assembly to selectively reverse the first rotational direction of the wind-up reel element and to selectively reverse the second rotational direction of the roll-up element.
In another exemplary embodiment, a method is provided for adapting a reel apparatus for a swimming pool cover motor having a rotatable drive shaft and a rope attached to the end of the swimming pool cover. The method comprises collecting the rope on a reel element and collecting the swimming pool cover on a roll-up element. The reel element is driven in a first rotational direction as the shaft rotates in a first direction. The roll-up element is driven in a second rotational direction as the shaft rotates in a second direction. The first rotational direction of the wind-up reel element and the second rotational direction of the roll-up element are reversed using a shift assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned features and other features and advantages of this disclosure will become more apparent and the disclosure will be better understood by reference to the following description of an exemplary implementation taken in conjunction with the accompanying drawings, wherein:
FIGS. 1A and 1B are generalized top views of right-hand and left-hand swimming pool cover motor assemblies;
FIGS. 2A and 2B are schematic representations of prior art gear mechanisms in the pool cover motor assemblies shown in FIGS. 1A and 1B ;
FIG. 3 is a plan partial view of a right-hand pool cover motor assembly, with a shift arm in a first position, in accordance with the present disclosure;
FIG. 4 is a plan partial view of the right-hand pool cover motor assembly of FIG. 3 with the shift arm in a second position, in accordance with the present disclosure;
FIG. 5 is a blown-up schematic view of the right-hand pool cover motor assembly shown in FIGS. 3 and 4 ;
FIGS. 6A and 6B are perspective and plan views of the reel assembly of the pool cover motor assembly shown in FIGS. 3 and 4 ;
FIGS. 7A and 7B are perspective and plan views of the drive cone assembly of the pool cover motor assembly shown in FIGS. 3 and 4 ;
FIG. 8A is an exploded perspective view of the torque limiter of the pool cover motor assembly shown in FIGS. 3 and 4 ;
FIG. 8B is a perspective view of the torque limiter of FIG. 8A and reel assembly of the pool cover motor assembly shown in FIGS. 3 and 4 ;
FIG. 9A is a plan partial view of a left-hand pool cover motor assembly, with a shift arm in a first position, in accordance with the present disclosure;
FIG. 9B is a plan partial view of the left-hand pool cover motor assembly of FIG. 9A , with the shift arm in a second position, in accordance with the present disclosure;
FIG. 10A is an exploded perspective view of the torque limiter of a left-hand pool cover motor assembly in accordance with the present disclosure; and
FIG. 10B is a perspective view of the torque limiter of FIG. 10A and the reel assembly of the left-hand pool cover motor assembly shown in FIG. 9A .
Throughout the drawings, identical reference numbers may designate similar, but not necessarily identical, elements. The examples herein illustrate selected implementations of the disclosure in certain forms, and such exemplification is not to be construed as limiting the scope of the disclosure in any manner.
DETAILED DESCRIPTION
The present apparatus and method described herein make it possible to have a universal shift or transposer mechanism that can be employed as either a right-hand system or a left-hand system for pool cover motor assemblies. The present apparatus and method uses the same gear mechanism for both right-hand and left-hand systems, only requiring a change in the orientation of one component in the gear mechanism to make the conversion. This simple gear structure eliminates the need to stock separate right-hand and left-hand pool cover motor assemblies, substantially reducing the inventory required for pool cover motor assemblies.
In addition, the embodiments of the present invention described herein incorporate a torque limited connected to the above gear mechanism. This arrangement utilizes the torque limiter to function both to limit the torque applied to the pool cover motor assembly and to connect the gear mechanism to the drive shaft of the motor. This structure substantially simplifies having a torque limiter as part of the system and reduces the cost of manufacturing accordingly.
Right-hand Pool Cover Motor System
Referring now to the drawings, and more particularly to FIG. 3 illustrates a portion of a right-hand pool cover motor system 70 according to one exemplary implementation. Motor system 70 includes a rope reel unit 72 (also referred to as “reel unit 72 ”) having dual side-by-side reels 74 , 75 for collecting ropes on spindles 76 , 77 from each of the two sides of a pool cover (not shown). Reel unit 72 is mounted on a bushing 79 to freely turn on a drive shaft 80 which comes from a pool cover motor (not shown). One side of reel unit 72 comprises a reel disc 78 , for interfacing with the gear mechanism to be discussed later.
A drive cone unit 82 is also mounted to freely turn on drive shaft 80 and attached by a roll-up collar 85 to a roll-up tube to the left of drive cone unit 82 (not shown) for collecting a pool cover. Drive cone unit 82 includes a cone piece 84 that is connected to a neck piece 86 and then to a drive cone disc 88 . Drive cone disc 88 interfaces with the gear mechanism 90 , as discussed below. As can be seen the pool cover motor system 70 is a right-hand system because the pool cover motor would be on the right side with the roll-up tube on the left hand side of the system 70 .
A gear mechanism 90 is shown between reel disc 78 and drive cone disc 88 . The gear mechanism includes a torque limiter 92 resistively mounted on drive shaft 80 by clamp ring 95 , to be discussed later. A shift base 94 is mounted on torque limiter 92 and a shift arm 96 pivotally mounted on shift base 94 . Reel disc lugs 100 are spaced around the surface 102 of reel disc 78 that faces toward gear mechanism 90 . Likewise drive cone disc 88 includes drive cone disc lugs 104 spaced around the surface 106 of drive cone disc 88 that faces toward gear mechanism 90 .
Gear mechanism 90 includes a shift arm 96 (also referred to as “shift member 96 ”) mounted on a pivot mount 98 on shift base 94 . The shift arm 96 pivots at 45 degrees relative to the axis of the drive shaft 80 . The pivot action of shift arm 96 responds to the pull of gravity to fall against the reel disc lugs 100 as the drive shaft 80 rotates in the direction A (clockwise, looking in from the end of shaft 80 ) as shown in FIG. 3 . This pivot action rotates torque limiter 92 that is fixedly mounted on drive shaft 80 . The rotation of torque limiter 92 places shift arm 96 behind and in contact with reel disc lug 100 a, thereby driving reel unit 72 also in direction A′. This rotation causes the rope (not shown) to wind up on reel unit 72 by coming in at the bottom of reels 76 and 77 , similar to that shown in FIG. 1A .
Referring now to FIG. 4 , the same portion of a pool cover motor system 70 is shown with the same components shown and described with respect to FIG. 3 . However, in FIG. 4 the drive shaft 80 is shown rotating in the direction B′ (counter-clockwise, looking in from the end of the shaft 80 ). This rotational direction B′ causes torque limiter 92 to rotate in the B′ direction. The pull of gravity causes shift arm 96 to shift behind and in contact with lug 104 a on cone drive disc 88 thereby causing it to rotate. This rotation of drive disc 88 causes cone drive 82 and roll-up tube (not shown) to rotate in the B direction, thereby collecting the pool cover that comes in at the top of roll-up tube, similar to that shown in FIG. 1A .
The foregoing description shows the simplicity and genius of the gear mechanism 90 . The reel unit 72 and the drive cone unit 82 are separately driven by the shift arm 96 , depending on the direction of rotation of drive shaft 80 . The only moving part is shift arm 96 , which simply pivots one of two directions to make contact with one of the appropriate lugs. The direction of rotation determines whether the reel unit 72 is to be driven to collect the rope, thereby extending the pool cover, or whether the drive cone unit 82 is to be driven to retract the pool cover.
FIG. 5 provides an exploded view of the pool cover motor system 70 . Drive cone unit 82 includes a roll-up tube collar 85 that connects to the roll-up tube (not shown). Drive cone unit also includes cone piece 84 , neck piece 86 and drive cone disc 88 , previously discussed. A plastic bushing 81 and a metal bushing 83 attach the drive cone unit 82 to freely turn on drive shaft 80 . Likewise, reel unit 72 is attached to freely turn on drive shaft 80 by a plastic bushing 72 and a metal bushing 73 .
The gear mechanism 90 is fixedly secured to drive shaft 80 by torque limiter 92 using the split hubs 91 and 93 . A split ring 97 is mounted on split hubs 91 and 93 and the combination is clamped onto the drive shaft 80 by clamp ring 95 . The torque limiter 92 has a base mount 99 on which the shift base 94 is secured. The shift arm 96 is pivotally secured on the shift base 94 . Various nuts, bolts, washers, pins and screws are shown in FIG. 5 having obvious functions of connecting the components shown.
FIGS. 6A and 6B show the structure of the reel disc 78 more clearly. Dual reels 74 and 75 are connected together on the same axis. The inner surface 102 of reel disc 78 has reel disc lugs 100 spaced around the periphery of surface 102 . A circular opening 103 extends through the center of reel disc 78 to accept bushings 71 and 73 , shown in FIG. 5 . Bushing 71 is also shown in place in FIG. 6B .
FIGS. 7A and 7B show the structure of the drive cone unit 82 more clearly. Roll-up tube collar 85 is connected to cone piece 84 . The drive cone disc 88 includes inner surface 106 with several drive cone disc lugs 104 spaced around the periphery. A circular opening 107 extends through the drive cone unit 82 to accept drive shaft 80 . Holes 109 are disposed in drive cone disc 88 for access purposes.
FIG. 8A shows the torque limiter 92 and gear mechanism 90 in more detail. The torque limiter 92 includes split hubs 91 and 93 , also shown in FIG. 5 . Only split hub 91 is visible in FIG. 8A . Hub 91 and 93 may be made of aluminum or other suitable material. A circular opening 120 extends through the center of hubs 91 and 93 to accommodate shaft 80 . Split ring 97 surrounds hubs 91 and 93 and is split to enable the ring 97 to be compressed to secure the torque limiter 92 on shaft 80 . Split ring 97 may be made of nylon or other suitable material to function as a split ring under compression. Outside ring clamp 95 surrounds split ring 97 and may be clamped tightly on ring 97 by a bolt 122 extending through a pinch member 124 . Clamp ring 95 may be made of cast stainless steel or other suitable material.
Torque limiter 92 is useful in preventing damage to the pool cover motor and other elements in the system in the event that the pool cover becomes jammed or the system otherwise cannot continue to rotate. In that case, the torque limiter acts as a breaker to prevent system damage. When the torque becomes greater than the clamping pressure of the ring clamp 95 , torque limiter 92 will allow slippage between the hub 91 , 93 and the split ring 97 . Outside ring claim 95 may be tightened so that torque limiter 92 may withstand any amount of torque desired. Typical thresholds where one might want to begin slippage could be in the range of from 400 inch pounds up to 1100 inch pounds.
The torque limiter 92 has a base mount 99 on top of ring clamp 95 . The shift base 94 is secured on base mount 99 by a bolt 126 extending through a hole 127 in base mount 99 , a corresponding hole 129 in shift base 94 and secured by a nut 128 . The shift arm 96 is pivotally secured on the shift base 94 by a bolt 130 extending through a hole (not shown) in pivot mount 98 to connect to a nut (not shown). The shift base 94 is mounted on base mount 99 so that the shift arm 96 pivots at a 45 degree angle relative to the vertical axis of torque limiter 92 . This enables the shift arm 96 to fall with the force of gravity against one of the lugs to drive either the reel unit 72 or the drive cone unit 82 , as described in connection with FIGS. 3 and 4 .
FIG. 8B shows torque limiter 92 mounted on drive shaft 80 . The shift arm 96 has pivoted to contact one of the reel disc lugs 100 a, so as to drive reel unit 72 in a counter-clockwise rotation, as described in connection with FIG. 3 .
Left-hand Pool Cover Motor System
FIGS. 9A and 9B partially show a left-hand pool cover motor system 170 according to another embodiment. This system is essentially a mirror image of the right-hand pool cover motor system shown in FIGS. 3 and 4 . As a result, the reference numbers used for similar element are offset by 100. Motor system 170 includes a rope reel unit 172 having dual side-by-side reels 174 , 175 for collecting ropes on spindles 176 , 177 from each of the two sides of a pool cover (not shown). Reel unit 172 is mounted on a bushing 179 to freely turn on a drive shaft 180 which comes from a pool cover motor (not shown). One side of reel 174 comprises a reel disc 178 , for interfacing with the gear mechanism to be discussed later.
A drive cone unit 182 is also mounted to freely turn on drive shaft 180 and attached to a roll-up tube (not shown) to the right of drive cone unit 182 for collecting the pool cover. Drive cone unit 182 includes a cone piece 184 that is connected to a neck piece 186 and then to a drive cone disc 188 . Drive cone disc 188 interfaces with the gear mechanism, as discussed below. As can be seen the pool cover motor system 170 is a left-hand system because the pool cover motor is on the left side and the roll-up tube is on the right-hand side of the system.
A gear mechanism 190 is shown between reel disc 178 and drive cone disc 188 . The gear mechanism includes a torque limiter 192 resistively mounted on drive shaft 180 by clamp ring 195 , to be discussed more later. A shift base 194 is mounted on torque limiter 192 and a shift arm 196 pivotally mounted on shift base 194 . Reel disc lugs 200 are spaced around the surface 202 of reel disc 178 that faces toward gear mechanism 190 . Likewise drive cone disc 188 includes drive cone disc lugs 204 spaced around the surface 206 of drive cone disc 188 that faces toward gear mechanism 190 .
Shift arm 196 is mounted on a pivot mount 198 on shift base 194 so that the shift arm 196 pivots at 45 degrees relative to the axis of the drive shaft 180 . The pivot action of shift arm 196 responds to the pull of gravity to fall against the reel disc lugs 200 as the drive shaft 180 rotates in the direction C′ (counter-clockwise, looking in from the end of shaft 180 ) as shown in FIG. 9A . This pivot action rotates torque limiter 192 that is fixedly mounted on drive shaft 180 . The rotation of torque limiter 192 places shift arm 196 in front and in contact with reel disc lug 200 a, thereby driving reel unit 172 also in direction C. This rotation causes the rope (not shown) to wind up on reel unit 172 by coming in at the bottom of reels 176 and 177 , similar to that shown in FIG. 3 , except that system 170 is a left-hand system.
Referring now to FIG. 9B , the same portion of a pool cover motor system 170 is shown with the same components shown and described with respect to FIG. 9A . However, in FIG. 9B , the drive shaft 180 is shown rotating in the direction D′ (clockwise, looking in from the end of the shaft 180 ). This rotational direction D′ causes torque limiter 192 to rotate in the D′ direction. The pull of gravity causes shift arm 196 to shift behind and in contact with lug 204 a on cone drive disc 188 thereby causing it to rotate. This rotation of drive disc 188 causes cone drive 182 and roll-up tube (not shown) to rotate in the D direction, thereby collecting the pool cover that comes in at the top of roll-up tube, similar to that shown in FIG. 4 , except that system 170 is a left-hand system.
The foregoing description further shows the simplicity and genius of the gear mechanism 90 . The reel unit and the roll-up tube are selectively driven by the shift arm 196 , depending on the direction of rotation of drive shaft 180 . The only moving part is shift arm 196 , which simply pivots one of two directions to make contact with one of the appropriate lugs. The direction of rotation determines whether the reel unit 172 is to be driven to collect the rope, thereby extending the pool cover, or whether the drive cone unit 182 is to be driven to retract the pool cover.
Further, the present invention enables the use of a gear mechanism 190 that is the same as the gear mechanism 90 , shown in FIGS. 3 and 4 except that the shift arm 196 has been rotated by 90 degrees to fall with the pull of gravity in a manner opposite to that described for a right-hand system.
FIGS. 10A and 10B illustrate more clearly the ease in shifting or transposing the gear mechanism of the present embodiments so as to accommodate a left-hand system, rather than a right-hand system. FIGS. 10A and 10B show a left-hand system in contrast to the right-hand arrangement shown in FIGS. 8A and 8B . FIG. 10A shows the torque limiter 192 that includes a split hub 191 and a second split hub 193 (not shown) on the opposite side of the torque limiter. A circular opening 220 extends through the center of hubs 191 and 193 to accommodate shaft 180 . Split ring 197 surrounds hubs 191 and 193 , being split to enable the ring 197 to be compressed to secure the torque limiter 192 on shaft 180 . Outside ring clamp 195 surrounds split ring 197 and may be clamped tightly on ring 197 by a bolt 222 extending through a pinch member 224 .
The torque limiter 192 has a base mount 199 on top of ring clamp 195 . The shift base 194 is secured on base mount 199 by a bolt 226 extending through a hole 227 in base mount 199 and a corresponding hole 229 in shift base 194 and then secured by a bolt 228 . The shift arm 196 is pivotally secured on the shift base 194 by a bolt 230 extending through a hole in pivot mount 198 to connect to a nut 232 . As shown, the shift base 194 is mounted on base mount 199 so that the shift arm 196 pivots at a 45 degree angle relative to the vertical axis of torque limiter 192 . This enables the shift arm 196 to fall with the force of gravity against one of the lugs to drive either the reel unit 172 or the drive cone unit 182 , as described with respect to FIGS. 8A and 8B .
Since the shift arm 196 for the left-hand system has been rotated 90 degrees relative to the shift arm 96 for a right-hand system, shift arm 196 will pivot and fall in response to gravity 90 degrees differently than discussed with respect to a right-hand system. However, since a left-hand system has the pool cover motor system components located in a mirror image to a right-hand system, the shift arm 196 still falls in the correct directions to drive the reel assembly 172 and the drive cone assembly 182 correctly for a left-hand system, as described above.
FIG. 10B shows torque limiter 192 mounted on drive shaft 180 . The shift arm 196 has pivoted to contact the reel disc lug 200 a, so as to drive reel unit 172 in a counter-clockwise rotation, as further described in connection with FIG. 9A .
In summary, the pool cover motor systems of the present embodiments offer a number of advantages. The gear mechanisms 90 and 190 for right-hand and left-hand systems of the present embodiments use simple components with only one moving part that pivots in response to gravity. Moreover, gear mechanisms 90 and 190 use the same components. Gear mechanism 90 , shown in FIG. 8A can easily be changed to become gear mechanism 190 shown in FIG. 10A by simply removing bolt 126 and rotating shift base 94 by 90 degrees relative to base mount 99 to place it in the position of shift base 194 shown in FIG. 10A . This simple gear structure eliminates the need to stock separate right-hand and left-hand pool cover motor assemblies. One pool cover motor assembly functions as either a right-hand or left-hand assembly by simply changing the gear mechanism as described above.
A further simplification over the prior art is provided by mounting the torque limiters 92 and 192 on drive shafts 80 and 180 , respectively, to connect to the respective gear mechanism 90 and 190 . Thus, the torque limiter provides the necessary fixed connection of the gear mechanism to the drive shaft, as described above. Accordingly, the use of a torque limiter connected to the gear mechanism performs both the functions of securing the gear mechanism to the drive shaft and limiting the amount of torque applied to the gear mechanism and to the pool cover motor assembly generally. This structure substantially simplifies the task of including a torque limiter as part of the pool cover motor assembly and reduces the cost of manufacturing accordingly.
While this disclosure has been described as having a preferred design, the present disclosure can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the disclosure using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this disclosure pertains and which fall within the limits of the appended claims. | A universal shift apparatus and method for a swimming pool cover motor has a rotatable drive shaft and a rope attached to the end of the swimming pool cover. A reel element collects the rope, and a roll-up element collects the swimming pool cover. A gear drive assembly on the rotatable drive shaft drives the reel element in a first rotational direction as the shaft rotates in a first direction and drives the roll-up element in a second rotational direction as the shaft rotates in a second direction. A shift assembly is associated with the gear drive assembly to selectively reverse the first rotational direction of the wind-up reel element and to selectively reverse the second rotational direction of the roll-up element. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a dual-side white light emitting device and a method of packaging the same.
[0003] 2. Description of the Prior Art
[0004] Compared with traditional cold cathode light source, the LED package components are smaller in size, lower in power consumption, while having a better performance in brightness, colorfulness and a higher reaction speed to allow for high-frequency operation. Besides, the components of LED package are environmentally friendly in that they are recyclable and impact resistant. Also they can be easily developed into thin-and-small sized products. All those advantages described above make the LED packages more competitive in the market. Generally speaking, the traditional LED package includes a package cup and a LED chip which is fixed on the cup. The traditional package cup has two inner terminals and two outer terminals. The inner terminals can be soldered to the positive electrode and negative electrode of the LED to form the electric connection. And the outer terminals are used to electrically connect to an opaque printed circuit board (PCB). In addition, the PCB also provides electric connection with external controlling device via its outer terminal which enables ECD to get electronically connected with the LED chip through the circuit of PCB and package cup.
[0005] As mentioned above, traditional method of LED integration is to mount the LED chip on the cup to form a LED package. Then, several LED package components are connected to PCB to form a LED device. In addition to the inevitable increase in its size, the complexity of production will also grow accordingly, which not only increases the production costs but also limits the application of LED device at the same time. Therefore, to produce a light LED device providing excellent optical effect is an important challenge in the development of LED technology.
SUMMARY OF THE INVENTION
[0006] Therefore, one of the objectives of this invention is to provide an LED device and the related package method to simplify the process and minimize the size. The provided LED device can also be used as a dual-side white LED.
[0007] According to the preferred embodiment of the present invention, an LED device includes a first transparent substrate, a plurality of LED chips mounted on the first transparent substrate to emit at least one light beam having a first wavelength, a transparent encapsulant encapsulating the LED chips, and a circuit formed on the first transparent substrate. The circuit is electrically connected to the LED chips. The LED chips emit a part of the light beam in one side of the first transparent substrate and emit a part of light beam penetrating through the first transparent substrate in the opposite side thereof.
[0008] From one aspect of the present invention, a method of packaging an LED device is disclosed. First, a first transparent substrate is provided. Subsequently, a circuit is formed on the first transparent substrate. Next, a plurality of LED chips are mounted on the transparent substrate, and electrically connecting the LED chips to the circuit. Furthermore, a transparent encapsulant is formed on the first transparent substrate to encapsulate the LED chips.
[0009] Since this invention placed the LED chip on the first transparent substrate, the LED package is also a dual-side white LED. Moreover, the LED chip is directly fixed on the first transparent substrate, and electrically connected with it. Therefore, this invention can simplify the production of LED and provide a light LED device.
[0010] These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a schematic structural diagram illustrating a LED device in accordance with a first preferred embodiment of the present invention.
[0012] FIG. 2 is a schematic top view illustrating the first transparent substrate shown in FIG. 1 .
[0013] FIG. 3 is a schematic explosion diagram illustrating the LED chips and the first transparent substrate shown in FIG. 1 .
[0014] FIG. 4 is a schematic explosion diagram illustrating a LED device in accordance with a second preferred embodiment of the present invention.
[0015] FIG. 5 is a schematic structural diagram illustrating the LED chips shown in FIG. 4 .
[0016] FIG. 6 is a schematic structural diagram illustrating a LED device in accordance with a third h preferred embodiment of the present invention.
[0017] FIG. 7 is a schematic structural diagram illustrating a LED device in accordance with a fourth preferred embodiment of the present invention.
[0018] FIG. 8 is a schematic flow chart illustrating a method of packaging a LED device according to a fifth preferred embodiment of the present invention.
DETAILED DESCRIPTION
[0019] Please refer to FIG. 1 through FIG. 3 . FIG. 1 is a schematic structural diagram illustrating a LED device 100 in accordance with a first preferred embodiment of the present invention, FIG. 2 is a schematic top view illustrating the first transparent substrate 124 shown in FIG. 1 , and FIG. 3 is a schematic explosion diagram illustrating the LED chips 128 and the first transparent substrate 124 shown in FIG. 1 . As shown in FIG. 1 , an LED device 100 can include a first transparent substrate 124 , a plurality of LED chips 128 mounted on the first transparent substrate 124 , and a transparent encapsulant 130 covering the LED chips 128 . The first transparent substrate 124 can include any light-pervious materials, such as a glass substrate or a plastic substrate. The LED chips 128 can be various types LED chips. It is preferred that each of the LED chips 128 may emits uniform light from both the top surface and the bottom surface, and the emitted light can has a wavelength in the range between 380 nanometers (nm) and 680 nm, but should not be limited thereto. Since the LED chips is disposed on the transparent substrate in the present invention, and the LED chip 128 may emits uniform light from both the top surface and the bottom surface, a dual-side light emitting device can therefore be provided. Although nine the LED chips 128 are shown in FIG. 1 for illustration, number of the LED chips 128 should not be limited by the drawings in the present invention.
[0020] The transparent encapsulant 130 can include any proper geometric shapes. In this embodiment, the transparent encapsulant may be semispherical encapsulants, and each of the semispherical encapsulants can encapsulate a corresponding LED chip 128 . The transparent encapsulant 130 can include insulating and light-pervious materials that can be solidified and waterproof, such as epoxy resin or silica gel. In addition, the LED chip 128 may be a LED chip with a small wavelength range of the light, so the LED chips 128 may not emit a predetermined color light or a pure white light directly. In order to provide a LED device 100 emitting light in predetermined color, the transparent encapsulant 130 may have at least one first phosphor material 146 . The first phosphor material 146 converts a part of the light beam having the first wavelength into a light beam having a second wavelength, and the remaining light beam having the first wavelength and the light beam having the second wavelength are mixed to form a predetermined color light. For example, when the light beam emitted by the LED chips 128 is blue light, the first phosphor material 146 may be a yellow-light emitting phosphor, and a yellow light emitted by the first phosphor material 146 and the remaining blue light are mixed to form a predetermined white light. Therefore, the LED device 100 may be a dual-side white light emitting device. In another embodiment, the first phosphor material 146 may include a red-light emitting phosphor and a green-light emitting phosphor. The red light and the green light emitted by the first phosphor material 146 , and the remaining blue light emitted by the LED chips 128 are mixed to form a white light.
[0021] In the first embodiment, the first transparent substrate 124 may optionally include a second phosphor material 148 to adjust the appeared light color emitted from the LED chips 128 through the first transparent substrate 124 , and the second phosphor material and the first phosphor material may includes the same materials. In another embodiment, the first transparent substrate 124 may include no phosphor.
[0022] As shown in FIG. 2 , the LED device 100 may include a circuit 150 disposed on the surface of the first transparent substrate 124 , and the LED chips 128 may be arranged as a dot matrix on the surface of the first transparent substrate 124 . The specific positions of the LED chips 128 should not be limited by FIG. 2 . For clearness, the LED chips 128 are shown as a transparent structure in FIG. 2 . In fact, the LED chips 128 may be opaque. The circuit 150 may include a plurality of first conductive lines 151 and a plurality of second conductive lines 152 . Both the first conductive line 151 and the second conductive line 152 have an external terminal 154 for electrically connecting the LED chips 128 to an external control device (not shown in the drawings). The control device may being electrically connected to both the first conductive lines 151 and the second conductive lines 152 to control the LED chips 128 . The LED chips 128 disposed in one line are parallel connected to one of the first conductive lines 151 , and the LED chips 128 disposed in one column are parallel connected to one of the second conductive lines 152 .
[0023] As shown in FIG. 3 , each of the LED chips 128 may have a first electrode 132 and a second electrode 134 . The first conductive lines 151 and the second conductive lines 152 may be electrically connected to the first electrodes 132 and the second electrodes 134 of the LED chips 128 respectively to control each of the LED chips 128 . In order to increase the reliability of connecting the LED chips 128 , a connecting material 155 may be included to mount the LED chips 128 on the first transparent substrate 124 . For clearness, both the LED chips 128 and the connecting material 155 are shown as a transparent structure in FIG. 3 . In fact, the LED chips 128 and the connecting material 155 may be opaque. It is preferred that the connecting material 155 is a eutectic metal, a silver colloid or a silver paste. The eutectic metal, the silver colloid or the silver paste can directly mount the LED chips 128 on the first transparent substrate 124 , and electrically connecting the LED chips 128 to the circuit 150 on the first transparent substrate 124 .
[0024] In the aforementioned embodiment, the transparent encapsulant includes semispherical encapsulants 130 to encapsulate the LED chips 128 respectively, so the individual shapes, sizes or the phosphor material of the transparent encapsulant 130 may be adjusted according to the product requirement or the types of the LED chips 128 , and the aforementioned embodiment may use fewer material amount of the transparent encapsulant 130 for the package. However, the present invention should not be limited thereto. In other embodiments, different packaging forms may be adopted in different structures of the LED devices in the present invention.
[0025] Please refer to FIG. 4 and FIG. 5 . FIG. 4 is a schematic explosion diagram illustrating a LED device 200 in accordance with a second preferred embodiment of the present invention, and FIG. 5 is a schematic structural diagram illustrating the LED chips 200 shown in FIG. 4 . As shown in FIG. 4 and FIG. 5 , the LED device 200 may include a first transparent substrate 124 , a second transparent substrate 126 , a plurality of LED chips 128 mounted on the first transparent substrate 124 and arranged in a dot matrix, a transparent encapsulant 230 disposed between the first transparent substrate 124 and the second transparent substrate 126 , and a circuit disposed on the first transparent substrate 124 and electrically connected to the LED chips 128 . The said circuit in this embodiment is similar to the circuit 150 , and not shown in FIG. 4 and FIG. 5 . The first transparent substrate 124 can include any light-pervious materials, such as a glass substrate or a plastic substrate, and a connecting material 155 may be included to mount the LED chips 128 on the first transparent substrate 124 , but should not be limited thereto.
[0026] The transparent encapsulant 230 may be coated on the first transparent substrate 124 , and is disposed on all the LED chips 128 . The transparent encapsulant 230 can include insulating and light-pervious materials that can be solidified and waterproof, such as epoxy resin or silica gel. In order to provide a LED device 100 emitting light in predetermined color, the transparent encapsulant 130 may also have at least one first phosphor material 146 . The first phosphor material 146 may include a yellow-light emitting phosphor, or include a red-light emitting phosphor and a green-light emitting phosphor, but should not be limited thereto.
[0027] Accordingly, this embodiment not only can simplify the process of forming the transparent encapsulant 230 , but also can protect both the top surface and the bottom surface of the LED chips 128 by the second transparent substrate 126 and the first transparent substrate 124 respectively. As a result, the LED device 200 is more suitable for applying as a dual-side light emitting device.
[0028] The present invention may further include spacers in order to keep a space between the first transparent substrate 124 and the second transparent substrate 126 for disposing the LED chips 128 . Please refer to FIG. 6 and FIG. 7 . FIG. 6 and FIG. 7 are schematic structural diagrams illustrating a LED device 300 and a LED device 400 in accordance with a third and fourth preferred embodiments of the present invention respectively. As shown in FIG. 6 , the main difference between the LED device 200 and the LED device 300 is that the LED device 300 may further include at least one spacer, such as a pad 156 , disposed around the LED chips 128 . For instance, the LED device 300 may further include a rectangular frame-like pad surrounding all the LED chips 128 to keep a space between the first transparent substrate 124 and the second transparent substrate 126 for disposing the LED chips 128 . The height H of the pad 156 is preferably larger than the thickness of the LED chips 128 , and the pad 156 may preferably include transparent materials. As shown in FIG. 7 , the main difference between the LED device 200 and the LED device 400 is that the transparent encapsulant 230 of the LED device 400 may further include a plurality of spacers, such as spherical spacers 158 in this embodiment. The spherical spacers 158 may directly mixed in materials of the transparent encapsulant 230 so as to keep a space between the first transparent substrate 124 and the second transparent substrate 126 for disposing the LED chips 128 . The diameter D of the spherical spacers 158 may larger than the thickness of the LED chips 128 , and the spherical spacers 158 may preferably include transparent materials.
[0029] Furthermore, a method of packaging a LED device is provided to the utilization of the transparent substrate in the present invention. Please refer to FIG. 8 . FIG. 8 is a schematic flow chart illustrating a method of packaging a LED device according to a fifth preferred embodiment of the present invention. This flow chart may shows the aforementioned steps of forming the structures of the first through the fourth embodiments, so the structures shown in FIG. 1 through FIG. 5 may also be referred to in the steps of FIG. 8 .
[0030] As shown in FIG. 8 , a transparent substrate is first provided, such as the first transparent substrate 124 . Subsequently, at least one metal evaporation process and at least one lithography process are performed in turn to form a circuit 150 on the surface of the first transparent substrate 124 . Thereafter, at least one spacer is disposed on the first transparent substrate 124 to support the first transparent substrate 124 and the following-formed second transparent substrate 126 . Next, a plurality of LED chips 128 are provided. The LED chips 128 may be directly mounted on the first transparent substrate 124 by a conductive glue or eutectic materials, and a eutectic metal, a silver colloid or a silver paste may electrically connecting the LED chips 128 to the circuit 150 on the first transparent substrate 124 . After that, a second transparent substrate 126 covering the LED chips 128 is provided.
[0031] Next, a transparent encapsulant is formed on the first transparent substrate 124 to encapsulate the LED chips 128 . For example, the transparent encapsulant 130 or the transparent encapsulant 230 may be formed, and the transparent encapsulants 130 , 230 may include at least one phosphor material. The transparent encapsulant may be disposed on the first transparent substrate 214 by coating process or may be disposed between the first transparent substrate 124 and the second transparent substrate 126 by filling process. Thereafter, a curing process may be preformed on the transparent encapsulants 130 , 230 to form the LED device.
[0032] In comparison with the traditional LED device, the present invention may include the following benefits. First, since a transparent substrate is utilized to support the LED chips in the present invention, the LED device can therefore be a dual-side light emitting device. Subsequently, since the transparent encapsulant or the transparent substrate may have phosphor materials to adjust the appeared light color of the LED device, the LED device may be a dual-side white light emitting device. In addition, since the LED chips are directly mounted on the transparent substrate, and may be directly connected to the circuit of the transparent substrate, processes of packaging the LED device may be simplified in the present invention, and a chip-level LED device can be provided. Furthermore, the LED chips of the present invention may be arranged as a dot matrix on the transparent substrate, and the circuit has metal traces arranged as a checker corresponding to the LED chips can turn on/off each of the LED chips. Thus, the LED device can be a display device that shows images or information on two opposite side, a lighting device that can adjust its brightness, luminance or light-emitting description, or a light source module. It is noticed that the arrangement of the LED chips should not be limited to the above-mentioned embodiment in the present invention, and the LED chips may be arranged in a single line, in random, or the present invention may even include only one LED chip in an LED device.
[0033] Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. | A light emitting diode (LED) device including a transparent substrate, a plurality of LED chips, a circuit, and a transparent encapsulant is provided. The LED chips are fixed on the transparent substrate, and utilized for radiating at least a light beam. The circuit is disposed on the transparent substrate and electrically connected to the LED chips. The transparent encapsulant is utilized for packaging the LED chips. The light beam of the LED chips can propagate from two opposite sides of the transparent substrate. Blue LED chips and the circuit of the transparent substrate can be directly soldered, and the phosphors are arranged to convert the wavelength of blue light, so a dual-side white light emitting device can therefore be provided. | 5 |
PRIORITY APPLICATION
[0001] This application claims the benefit of priority under 35 U.S.C. §119 of U.S. Provisional Application No. 62/084,211, filed on Nov. 25, 2014, the content of which is relied upon and incorporated herein by reference in its entirety.
BACKGROUND
[0002] Multi-Dwelling Unit (MDU) cable installations utilize drop (or “home-run”) cables that extend to tenant living units. Conventional surface or “facade” installations involve attaching the cable directly to a wall using fasteners such as cable clips, clamps, and cable ties. This is problematic for several reasons: 1) it is time-consuming and tedious to evenly space and then install the fasteners, 2) a variety of fasteners must be kept in inventory to match building aesthetics, and 3) the installed fastener are unsightly and draw attention to the cable installations. Cables may also be stapled directly to a mounting surface, but this can result in puncture of the communication section of the cable, but the staples remain visible to building occupants, and works well on a limited number of surfaces, such as wood.
SUMMARY
[0003] According to one embodiment, a method of installing a fiber optic cable on a surface comprises providing a cable comprising a communication section and an attachment section connected to the communication section, the communication section having at least one optical fiber, placing the cable adjacent the surface, securing the attachment section to the surface with at least one attachment member, and moving the communication section with respect to the attachment section so that the communication section at least partially overlaps a facing surface of the attachment section.
[0004] According to another embodiment, a fiber optic cable comprises communication section having at least one optical fiber, and an attachment section connected to the communication section. The communication section may be configured to rotate with respect to the attachment section so that the communication section at least partially overlaps a facing surface of the attachment section. The communication section and the attachment section may comprise a common, unitary extrudate polymeric material, and the web may have a thickness that is less than 25% of a major dimension of the communication section.
[0005] Additional features and advantages will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments as described herein, including the detailed description which follows, the claims, as well as the appended drawings.
[0006] It is to be understood that both the foregoing general description and the following detailed description are merely exemplary, and are intended to provide an overview or framework to understanding the nature and character of the claims. The accompanying drawings are included to provide a further understanding, and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiment(s), and together with the description serve to explain principles and operation of the various embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is perspective view of a section of a fiber optic cable according to a first embodiment;
[0008] FIG. 2 illustrates the cable of FIG. 1 after installation on a surface; and
[0009] FIG. 3 is perspective view of a section of a fiber optic cable according to a second embodiment.
DETAILED DESCRIPTION
[0010] FIG. 1 is a perspective view of a section of a fiber optic cable 100 according to a first embodiment, prior to installation on a surface 170 . The cable 100 comprises a communication section 110 having a major dimension 112 . In FIG. 1 , the major dimension 112 is illustrated as a width, or more specifically in FIG. 1 , as a diameter of the communication section 110 . The communication section 110 is connected to an attachment section 120 that serves to install the cable 100 to the surface 170 . The cable 100 is suitable for use as, for example, a drop cable in a fiber optic deployment in an MDU, and in other environments.
[0011] The communication section 110 has a core 130 that accommodates one or more optical fibers 132 . The core 130 could alternatively or in addition include electrically conductive components, such as copper conductors (not illustrated). The attachment section 120 is integrally attached to the communication section 110 , and the two sections can comprise, for example, a unitary extrudate 134 formed by the same extrusion process (e.g., through coextrusion), from, for example, a common polymeric material. The portion of the communication section 110 surrounding the fibers 132 can be generally referred to as the jacket 136 of the cable. According to one embodiment, the attachment section 120 can be extruded from a different material than that of the jacket 136 , such as a polymer having different material properties than those of the communication section that can be secured to the material forming the jacket 136 through a coextrusion process or by other means.
[0012] The exemplary communication section 110 can have a generally tubular shape in which the core 130 is formed along the centerline of the tube formed by the jacket 136 . The optical fibers 132 extend along the length of the cable 100 . The core 130 may accommodate additional components, such as strength members, water blocking components, electrical conductors, and other components (not illustrated). The exemplary communication section 110 is described by way of example as having a ‘diameter’, although it is understood that even cables sold as ‘round’ or ‘circular’ may deviate form a perfect circular section, particularly after installation. Other cable cross-sections, such as oblong, or other tubular forms may also be used in the communication section 110 .
[0013] The exemplary attachment section 120 may have a flat, plate-like web 140 with opposed, generally flat sides. The web 140 may have a thickness that is less than, for example, 25% of the major dimension 112 , and a length 144 that is at least 50% of the major dimension 112 . According to another embodiment, the web 140 has a thickness that is less than 15% of the major dimension 112 , and a length 144 that is at least 75% of the major dimension 112 .
[0014] The web 140 can include one or more apertures 146 to facilitate attachment of the cable 100 to a surface. The apertures 146 can be configured to receive, for example, nails, screws, and tacks, or they may be spaced at regular intervals on the cable 100 to receive the points of a staple of a predetermined size. The web 140 can be relatively uniform in thickness, although a bead 148 can extend along the distal edge of the attachment section 120 to prevent tears in the web 140 . Although the cable 100 is illustrated as symmetric about CL 1 , the cable may be tailored to provide desired to provide specific installation and aesthetic properties. For example, one side of the web 140 , which is intended to abut the surface 170 during installation, can be generally flat so that it conforms to the surface 170 . The outwardly-facing surface 156 can have aesthetic features, such as patterning, designed to emulate the visual appearance of the surface 170 so as to reduce the visual impact of the cable installation. The apertures can also be configured so that they do not extend wholly through the web, and can instead be indentations or recesses that aid in the placement of attachment members during installation.
[0015] Prior to installation, the cable 100 has a height 160 , extending from one end of the communication section 110 to a distal end of the attachment section 120 . The height 160 is measured from an end of the attachment section 120 to a distal end of the communication section 110 .
[0016] FIG. 2 illustrates the cable 100 installed on a surface 170 . The surface 170 may be, for example, a vertical or horizontal surface of a building, such as wood, drywall and other surfaces. In the illustrated embodiment, the surface 170 is a vertical building surface. To install the cable 100 on the surface 170 , the cable 100 is placed adjacent the surface 170 . Attachment members, such as nails, tacks, or staples (not shown), are then forced through the apertures 146 into the surface 170 . Alternatively, the attachment members can be hammered or pressed etc. directly through the web 140 without using apertures or recesses.
[0017] After securing the attachment section 120 to the surface, the communication section 110 can then be manually rotated or rolled over the web 140 , as indicated by the arrow in FIG. 2 to a ‘closed’, or installed position. In this position, the communication section 110 at least partially overlaps and obscures a facing surface of the attachment section 120 . Conventional ties or other means can be used to secure the cable 100 in the installed position.
[0018] The attachment section 120 may also include a flexible strength member (not shown), such as an elongate rod extending the cable length, that allows an externally extruded feature to clip into the strength member after installation of the cable to the mounting surface. This solution obviates the need for cable ties to secure the cable in its installed position.
[0019] The cross section of the cable 100 , and the extrudate material 134 can be selected to allow for the communication section 110 to rotate under the influence of gravity upon attachment to the surface 170 . The communication section 110 in this embodiment would be placed vertically above the attachment section 120 during installation. This solution also obviates the need for cable ties to secure the cable in its installed position.
[0020] According to one aspect, rotation of the communication section 110 reduces the overall footprint of the cable 100 without removing any cable material. The height of the cable, for example, changes from the height 160 shown in FIG. 1 , to the height 176 shown in FIG. 2 . The installed height 176 can be, for example, less than 90% of the original height 160 . According to another embodiment, the installed height 176 can be, for example, less than 80% of the original height 160 . Rotation of the communication section 110 can also be configured to hide attachment members from view, as shown in FIG. 2 , providing an aesthetically pleasing installed profile.
[0021] If the cable 100 is installed along a horizontal path on a vertical surface, the lowest part of the communication section 110 can be configured to be lower than the apertures 146 , so that the communication section 110 wholly or partially obscures the attachment members from view. If no apertures are used, any attachment members hammered through the web 140 can be placed high enough on the web 140 so that the communication section 110 covers the members after rotation of the communication section 110 .
[0022] According to another aspect, the cable 100 allows for reduced installation time on a variety of building surfaces, using a wide variety of conventional, commercially available fasteners.
[0023] FIG. 3 is perspective view of a section of a fiber optic cable 200 according to a second embodiment. The cable 200 may have a communication section 210 , an attachment section 220 and a core 230 that are similar in structure to those of the cable 100 . However, the centerline CL 2 of the attachment section 220 is offset from the centerline of the communication section 210 . The attachment section 220 can have a mounting face surface 222 that is generally continuous with the exterior of one side of the communication section 210 . The attachment section 220 is integrally attached to the communication section 210 , and the two sections can comprise, for example, a unitary extrudate formed by the same extrusion process from a common polymeric material.
[0024] To install the cable 200 on a surface, the mounting face surface 222 is placed against a mounting surface 170 , and attachment member members are either pounded through the web 240 , or through apertures (not shown) in the web 240 . The offset location of the attachment section 220 means that the communication section 210 can rotate more easily in the direction of the arrow with respect the attachment section 220 . The cable 200 is also easier to install as the side of the cable 200 pressed against the mounting surface during installation is essentially flat. The installed height can be, for example, less than 90% of the original height. According to another embodiment, the installed height can be, for example, less than 80% of the original height. Rotation of the communication section 210 can also be configured to hide attachment members from view.
[0025] Unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not actually recite an order to be followed by its steps or it is not otherwise specifically stated in the claims or descriptions that the steps are to be limited to a specific order, it is no way intended that any particular order be inferred.
[0026] It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the invention. Since modifications combinations, sub-combinations and variations 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 their equivalents. | A fiber optical cable has a communication section and an attachment section. The attachment section is meant to be installed below the communication section, so that when the cable is mounted to a surface, the communication section drops vertically with respect to the attachment section, thereby obscuring part of the attachment section from view. The attachment section may also be moved manually over the attachment section so as to overlap the attachment section. Ties or other means may be used to retain the communication section in the overlapped position. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to stackable block members and a method of using the block members to build retaining walls. More particularly, the present invention relates to stackable, pre-cast block members having an improved connection mechanism allowing retaining walls to be anchored in place so as to minimize movement of the block members after construction.
Retaining walls have long been used to prevent berms, slopes and embankments from sliding and slumping. Additionally, retaining walls are used as one mechanism to control soil erosion. These structures are often used to support naturally occurring slopes and embankments while also accommodating the construction of artificial slopes, embankments, planters, stairways, stream banks and similar earthworks. In these applications Pre-cast concrete blocks are a particularly useful and versatile material for constructing retaining walls.
A number of complex, and expensive, retaining wall systems have been developed for building relatively tall retaining walls (i.e. those over about 12 feet in height). The construction of such tall retaining walls typically involves (or requires) soil studies and professional engineering support. In typical conditions, retaining walls up to approximately 40 inches in height may be constructed from concrete blocks of reasonable size and the concrete blocks alone are sufficient to prevent sliding and slumping. These relatively short walls are often designed and built by contractors and home owners and do not require either soil studies or professional engineering support.
Many applications exist which require retaining walls taller than 40 inches in height, including commercial/industrial applications. Generally speaking, concrete blocks of reasonable size alone are not sufficient for these retaining walls and some method of holding the concrete blocks in position is required.
As one example of an engineered solution, a three-block system which uses wall blocks mechanically connected to and anchored by a trunk block and a tail block is shown in U.S. Pat. No. 5,350,256 to Hammer. In that system, each of the wall blocks in each course of wall blocks is connected to a trunk block which is in turn mechanically connected to a tail block. The combination of the trunk block and the tail block serves to anchor the wall block. The relative sizes of the blocks used in that system are such that the weights of the trunk block and the tail block are each nearly as great as the weight of the wall block. Unfortunately the number of trunk and tail blocks required, and the labor necessary to lay those additional blocks drives up the cost of constructing such a retaining wall.
U.S. Pat. No. 5,820,304 to Sorheim et al. describes an alternate system to achieve anchoring of the wall. More specifically, a network of uniform anchor blocks can be attached to facing blocks to provide the necessary anchoring behind the wall.
Additional systems of wall blocks which rely upon a mechanical connection between wall blocks in adjacent courses are shown in U.S. Pat. No. 5,294,216 to Sievert, and U.S. Pat. No. 5,505,034 to Dueck. Such systems rely upon the weight of the wall blocks and are not sufficient for building retaining walls of even an intermediate height.
A method of anchoring wall blocks with a lattice-like grid (i.e., “geogrid”) connected to the wall blocks is shown in U.S. Pat. No. 5,511,910 to Scales. Such grids are positioned between stacked wall blocks and extend rearwardly away from the blocks. The grids are then buried within fill material behind the retaining walls to anchor the blocks in place. While attachment of the geogrid is conveniently achieved, this structure becomes difficult to use with larger blocks (e.g. 24″×36″ blocks).
Another alternative to the design disclosed in the '910 patent to Scales is illustrated in FIG. 1 . As shown in FIG. 1 , each wall block includes a channel on a top surface thereof that is structured to receive an elongate bar member. A grid structure is wrapped around the elongate bar member prior to positioning the bar member within the channel. The grid structure is then routed toward the rear of the block, and a second block is stacked on top of the first block. As a result, the grid structure is “sandwiched” between the first and second blocks.
One problem with designs such as those disclosed in the '910 patent to Scales and illustrated in FIG. 1 is the interference of the grid structure with successively stacked blocks. In particular, the grid structure introduces an additional thickness between the top surface of a first block and the bottom surface of a second block stacked on top of the first block. For example, the thickness of the grid structure may be about 0.125 inches. However, as more and more blocks are stacked on top of one another, the combined thickness of each grid structure adds up quickly and causes the retaining wall to “lean forward” (i.e., become “non-vertical”) and lose stability.
Generally, most prior retaining wall block assemblies utilized friction between wall face units to generate a “connection.” Differential settlement or other problems would often diminish or eliminate this connection. Other types of connections included, for example, a bar “botkin connection.” However, this type of connection had a lesser capacity than the grid structure itself, making the connection the weak link.
Therefore, a need exists for a retaining wall system which: (a) utilizes pre-cast wall blocks of large size and weight; (b) provides a cost effective method of anchoring the wall blocks; (c) eliminates the positioning of a grid structure between the top surface of one wall block and the bottom surface of another wall block; and (d) can be built to significant heights while minimizing the risk of tipping or becoming otherwise unstable.
SUMMARY OF THE INVENTION
To address the above-discussed needs, a retaining wall block is provided which includes integrated attachment mechanisms easily accommodating geogrid type stabilizing structures. Further, the attachment mechanism allows for more convenient handling of the blocks themselves. Further, the retaining wall block is easily constructed to include this connection mechanism in a manner that is efficient and effective.
The retaining wall blocks in the present invention are pre-cast blocks fabricated utilizing predesigned molds. As common in the fabrication of pre-cast blocks, a concrete or a cement mixture is poured into the mold and allowed to appropriately cure. As is typical, the mold includes an open top end, thus exposing a portion of the concrete. As anticipated, the block itself is designed to cause this exposed surface to be the back or rear portion of the block. In one embodiment of the present invention, this exposed surface is utilized to accommodate the incorporation of an integral attachment mechanism within the fabricated block itself. In this case, an attachment structure is prefabricated and on hand during the block forming process. Once concrete has been poured into the mold, this attachment structure is then inserted into the wet concrete at the open end of the mold itself. Subsequently, the concrete is allowed to harden thus causing the holding structure to be an intracal portion of the block itself.
Utilizing a similar process, blocks of different types can be easily formed. Further, wall-panels or other structures can also be easily fabricated.
The retaining wall block or panel assemblies fabricated as outlined above have many benefits: The retaining wall block assemblies may be made of materials already utilized or produced by the pre-cast concrete industry, thus reducing out of pocket costs. Further, the retaining wall block assemblies are constructed with reduced complexity, thus helping to control costs and increase productivity.
As an alternative, the block assembly could be formed in one mold. This approach somewhat complicates the mold to be used, but would achieve a similar result. The mold involved would require structures to form the attachment mechanism, and would need to accommodate removal. This option would require the block to be formed side down, as opposed to face down. Alternatively, such a block assembly could be formed face up, with the face surface finished in some other process.
Creating the retaining wall block assemblies as discussed above allows the use of multiple components and materials. Additionally, the connection mechanism can be formed prior to forming the retaining wall block. Also, the connection mechanism can be used as a lifting device, thus eliminating the need for such a structure on top of the retaining wall block.
In the present block assembly, a concrete of differing strength can be used in the connection mechanism, thus optimizing the use of higher cost materials (e.g. locating them at the point of highest load concentration).
The retaining wall block assemblies solve the engineering problem of attaching a grid structure to a concrete panel using the integrated connection mechanism. This approach provides a cheaper and structurally superior method.
The two part construction of the connection mechanism takes advantage of the high compression strength of concrete and the high tensile strength of steel.
The connection mechanism of the present invention may include reinforcing components encased in high density concrete as opposed to a coating that may be damaged or corrode over time, adding to the structural superiority of the connection mechanism. Further, the connection mechanism may include curved edges to protect the grid structure from being damaged.
When used to create a wall structure, the retaining wall blocks are allowed to settle without generating additional shears on the grid structure due to the wrap-around configuration of the grid structure. This enables the grid structure to rotate and not just shear. In a similar manner, the connection mechanism accommodates the use of more economical strips of high strength grid structure. These strips are more easily handled than large mats and are a more efficient use of material.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram illustrating one embodiment of a prior art retaining wall block anchoring system.
FIG. 2 is a top perspective view of one exemplary embodiment of a retaining wall block assembly in accordance with the present invention, which includes a retaining wall block and a connection mechanism.
FIG. 3 is an exploded perspective view of the retaining wall block assembly of FIG. 1 .
FIG. 4 is a cross-sectional view of the connection mechanism illustrating the position of a block connector disposed therein.
FIG. 5 is a cross-sectional view of the connection mechanism of FIG. 4 .
FIG. 6 is a side view illustrating a pair of retaining wall block assemblies incorporating a stabilizing grid structure.
FIG. 7 illustrates an alternative embodiment, which includes a wall panel and a related connection mechanism.
FIG. 8 is a cross-sectional view of another alternative embodiment of a connection mechanism.
FIG. 9 is a side view of a pair of retaining wall block assemblies having the connection mechanism of FIG. 8 attached thereto.
FIG. 10 is a cross-sectional view of a further alternative embodiment of a connection mechanism having a block connector that is completely encased within concrete.
FIG. 11 is a cross-sectional view of yet another alternative embodiment with the reinforcing member and legs configured at angles.
FIG. 12 is a cross-sectional view of an additional embodiment having a curved reinforcing member.
FIG. 13 is a cross-sectional view of another alternative embodiment, using a curved reinforcing member which is completely encased in concrete.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 2 a top perspective view of one exemplary embodiment of a retaining wall block assembly 10 is illustrated. Retaining wall block assembly 10 generally includes retaining wall block 12 and connection mechanism 14 attached thereto.
Retaining wall bock 12 may be formed using numerous methods and from numerous materials as will be appreciated by those skilled in the art. However, for purposes of example and not limitation, the present discussion will focus on a retaining wall block 12 formed by pouring concrete into a casting shell.
As shown in FIG. 2 , retaining wall block 12 includes front surface 16 , rear surface 18 , first side 20 , second side 22 , top surface 24 , and bottom surface 26 . In this particular embodiment, retaining wall block 12 is shaped with unequal face lengths, wherein the length L 1 of front surface 16 is greater than the length L 2 of rear surface 18 , and wherein first and second sides 20 and 22 form an obtuse angle with rear surface 18 . Those skilled in the art will appreciate that retaining wall blocks having various shapes, sizes, surface lengths, and/or a numbers of “sides” are contemplated and within the intended scope of the present invention.
As shown in FIG. 2 , connection mechanism 14 is coupled to and extends from a rear portion of retaining wall block 12 . Connection mechanism 14 generally includes main body 30 , first arm 32 , and second arm 34 . When assembled as shown in FIG. 2 , end portions 36 and 38 of first and second arms 32 and 34 , respectively, are integral with a rear portion of retaining wall block 12 . These components form a connection slot 39 formed between main body 30 and rear portion of retaining wall block 12 . Furthermore, inner surface 40 of connection main body 30 includes curved or rounded edges to help prevent a coupled grid structure from tearing or otherwise becoming damaged (discussed in further detail to follow). In addition, inner surfaces 42 and 44 of first and second arms 32 and 34 , respectively, may also include curved edges similar to inner surface 40 of main body 30 .
FIG. 3 is an exploded perspective view of the retaining wall block assembly 10 of FIG. 2 . As shown in FIG. 3 , connection mechanism 14 further includes an internal strengthening member 48 having main body portion 50 , first arm 52 , and second arm 54 . First arm 52 includes first flange member 56 extending therefrom, while second arm 54 includes a similar flange member 58 . In one embodiment, internal strengthening member 48 is preconfigured reinforcing bar material which is typically available to most concrete companies. Other materials contemplated may include other steel or metal materials, coated metals, carbon fiber, fiberglass, fiberglass reinforced plastic, or other composite materials depending on the particular application.
As stated above, retaining wall block 12 may be formed from a concrete material, such as wet cast or low slump concrete. Connection mechanism 14 may also be formed from materials similar to those used to form retaining wall block 12 , although using such similar materials is not necessary. In one exemplary method of constructing retaining wall block assembly 10 , connection mechanism 14 may be formed prior to forming retaining wall block 12 , such as one or more days in advance of retaining wall block 12 . This allows first and second flange members 56 and 58 (along with a portion of first and second arms 52 and 54 ) of connection mechanism 14 to be positioned within the un-solidified concrete being used to form retaining wall block 12 . Thus, when the concrete of retaining wall block 12 solidifies, connection mechanism 14 will be securely coupled to retaining wall block 12 due to the hardening of concrete around first and second flange members 56 and 58 . Further, a portion of first and second arms 32 and 34 may also be submerged in the unsolidified concrete. The angle portions of flange members 56 and 58 function similar to “hooks” and are structured to prevent first and second arms 52 and 54 , respectively, from being pulled from within retaining wall block 12 when an opposing force is applied to connection mechanism 14 .
As an alternative, the connection mechanism 14 and block 12 could be formed in a single mold. Naturally, this approach requires a more complex mold, and must specifically accommodate the connection mechanism (e.g. form this structure while also allowing the mold to be removed). Also, an appropriate holding structure would be necessary to position internal strengthening member. While the mold will be more complicated, a single molding step can be used.
As those skilled in the art will appreciate, internal strengthening member 48 may be formed from any suitable material that has a high tensile strength. For example, internal strengthening member 48 may be formed from a steel bar as is typical for many concrete products. However, numerous other materials such as various other metals, fiberglass, fiberglass reinforced plastics, carbon fiber and the like, are also contemplated.
Connection mechanism 14 is able to provide improved structural superiority due to its “two part” construction. In particular, the two part construction of connection mechanism 14 of the above described embodiment takes advantage of the high compression strength of concrete as well as the high tensile strength of steel. More specifically, this design provides an advantage over other products which simply include various elements embedded into the concrete, as such elements typically act alone in shear and/or bending. Conversely, the two part construction of the present invention allows the two materials to work in conjunction with one another.
In alternative embodiments, retaining wall block 12 and connection mechanism 14 may be made from different materials, such as different types of concrete. This allows, for example, a stronger concrete to be used at the point of highest load concentration (i.e. in the connection mechanism 14 ) and a slightly weaker concrete to be used in retaining wall block 12 where the load concentration is not as high. As a result, retaining wall block assemblies may be constructed so as to maximize strength in the critical areas as well as to minimize overall cost.
As those skilled in the art will appreciate, moving a large and heavy retaining wall block during construction of a retaining wall can be very awkward and difficult. Connection mechanism 14 helps to alleviate these problems by also serving as a handle or lifting device for moving retaining wall block 12 .
FIG. 4 is a cross-sectional view of connection mechanism 14 illustrating the position of internal strengthening member 48 within main body 30 , first arm 32 , and second arm 34 . As shown in FIG. 4 , main body portion 50 , first arm 52 , and second arm 54 form a generally “U” shaped member mirroring the structure of connection mechanism 14 . Thus, first and second arms 52 and 54 each form an angle A with main body portion 50 of internal block connector 48 that is about 90 degrees. However, in alternative embodiments, the shape of internal block connector 48 as well as its position within connection mechanism 14 may be modified without departing from the intended scope of the present invention. For example, first and second arms 52 and 54 of internal block connector 48 may alternatively form an angle with main body portion 50 that is greater or less than about 90 degrees.
FIG. 5 is a cross-sectional view of connection mechanism 14 shown and described above in reference to FIGS. 2-4 . More specifically, this cross-section is shown along section lines 5 - 5 shown in FIG. 4 . As illustrated, internal strengthening member 48 is approximately centered within connection mechanism 14 in the vertical direction V, while being off-centered in the horizontal direction H. This positioning provides strength advantages when subject to horizontal pulling forces. However, in other embodiments, internal strengthening member 48 may be approximately centered within connection mechanism 14 or off-centered by other amounts and/or directions without departing from the intended scope of the present invention.
As shown in FIG. 5 , connection mechanism 14 has rounded edges 60 on each of the four corners. The presence of rounded edges 60 helps to protect a grid structure positioned adjacent connection mechanism 14 from the rough or squared off edges of the connection mechanism that would otherwise be present, thereby minimizing the possibility of cutting or otherwise damaging the grid structure.
Connection mechanism 14 has a vertical height 61 that may be selected based upon the size of the retaining wall block with which it will be used. However, in one exemplary embodiment, vertical height 61 may be about 6 inches.
Although internal strengthening member 48 is shown as having a generally circular cross-section, those skilled in the art will appreciate that numerous other cross-sectional shapes are also contemplated. For example, alternative embodiments of internal strengthening member 48 may have a generally oval, square, or rectangular cross-sectional shape. In other embodiments, the cross-sectional shape and/or dimensions of the block connector may vary at different points along the block connector. For instance, in one embodiment, first and second arms 52 and 54 may have a generally circular cross-sectional shape with a first diameter, while main body portion 50 may have a generally circular cross-sectional shape with a second diameter that is different than the first diameter. In another embodiment, first and second arms 52 and 54 may have a generally circular cross-sectional shape, while main body portion 50 may have a generally square cross-sectional shape. The actual configuration may also be somewhat dependent upon the particular materials utilized and the manufacturing methods utilized to create internal strengthening member 48 .
FIG. 6 is a side view of a pair of retaining wall block assemblies 10 in accordance with the present invention illustrating the positioning of a grid structure G and the stackability of blocks 10 . In particular, a grid structure G may be wrapped around inner surface 40 (not shown) of connection mechanism 14 . Because connection mechanism 14 is designed with rounded edges 60 (as shown in FIG. 5 ), grid structure G contacts only smooth, formed concrete. As a result, the wear on grid structure G is minimized, thereby greatly reducing the possibility that grid structure G may fail (such as by breaking or otherwise becoming damaged) after the retaining wall is constructed.
During construction of a retaining wall, a first retaining wall block assembly 10 is set in place, and a fill material such as dirt or gravel is inserted behind retaining wall block 12 . Next, a first layer 70 of grid structure G is positioned on top of the fill material and wrapped around connection mechanism 14 . Another layer of fill material is then inserted between first layer 70 and second layer 72 . Yet another layer of fill material is then inserted on top of second layer 72 , and the process continues with additional block assemblies until the desired wall height has been reached.
As shown in FIG. 6 , top surface 24 of retaining wall block 12 may also include a protrusion 74 structured to cooperate with a recess 76 in bottom surface 26 of a retaining wall block 12 . The combination of protrusion 74 and recess 76 serves as a “locking system” and may help to prevent movement of stacked retaining wall blocks 12 relative to one another after construction of the retaining wall.
FIG. 7 is a cross-sectional view of a wall assembly 10 A, which is one alternative embodiment in accordance with the present invention. In particular, wall assembly 10 A is similar to retaining wall block assembly 10 described above, with retaining wall block 12 being replaced by a taller, thinner concrete wall panel 12 A. As illustrated, wall panel 12 A includes a pair of connection mechanisms 14 similar to the connection mechanism previously described coupled to and extend from rear surface 18 A. Once again, each connection mechanism 14 includes internal strengthening member 48 , which may be formed from preconfigured reinforcing bar material typically available to concrete companies. Furthermore, internal strengthening member 48 includes a pair of arms with a corresponding pair of flange members extending into wall panel 12 A, which are structured to prevent the arms from being pulled from within wall panel 12 A when an opposing force is applied to connection mechanism 14 .
Optionally, each flange member may be structured to engage a vertical reinforcing member 80 positioned within wall panel 12 A. Vertical reinforcing member 80 may also be formed from a preconfigured reinforcing bar material similar to that used to form internal strengthening member 48 . As outlined above in relation to the blocks 12 , connection mechanisms could be formed prior to the fabrication of wall panels 12 A, thus allowing for easy “attachment” during the fabrication process.
In addition, a cap member 82 structured to act as a transport dunnage may be coupled to a back side of each connection mechanism 14 . Cap member 82 may be formed from any suitable material, including plastics and the like.
As illustrated in FIG. 7 , a separate grid structure G may be wrapped around each connection mechanism 14 in a manner similar to that previously described in order to construct a wall by stacking a plurality of wall panels 12 A on top of one another and burying the grid structures G in a fill material. While FIG. 7 illustrates a pair of connection mechanisms 14 evenly distributed across wall panel 12 A, alternative configurations are possible. For example, in applications where only a portion of wall panel 12 A will be backfilled, only a single connection mechanism 14 will be necessary. In this alternative example, additional wall members would obviously not be stacked on top of the existing wall member 12 A.
FIG. 8 is a cross-sectional view of an alternative connection mechanism 114 . Connection mechanism 114 is similar to connection mechanism 14 described above in reference to FIGS. 2-7 , however, has a vertical height 116 that is greater than that previously discussed. In one embodiment, the vertical height 116 is about twice the corresponding vertical height of connection mechanism 14 , or about 12 inches. In addition to having a greater vertical height, connection mechanism 114 also includes a second internal strengthening member 48 to provide additional strength advantages when subject to horizontal pulling forces. Those skilled in the art will appreciate that the number and location of block connectors within connection mechanism 114 may vary from the embodiment shown in FIG. 8 without departing from the intended scope of the present invention.
FIG. 9 is a side view of a pair of retaining wall block assemblies 110 in accordance with the present invention being stacked in order to create a retaining wall. Each of the retaining wall block assemblies 110 includes connection mechanism 114 coupled to a retaining wall block 112 . Retaining wall block 112 may be similar in size to retaining wall block 12 previously described in reference to FIGS. 2-7 . Alternatively, retaining wall block 112 may have a vertical height 118 that is greater than the corresponding vertical height of retaining wall block 12 in order to better accommodate the larger connection mechanism 114 .
As shown in FIG. 9 , a grid structure G may be wrapped around connection mechanism 114 in the manner previously described. When assembling a retaining wall with retaining wall blocks 112 , the 12-inch vertical height of connection mechanism 114 allows a 12-inch layer of fill to be inserted between the layers of the grid structure G, such as first and second layers 70 and 72 . This may be important because, for example, the building code may require layers of fill material that are 12 inches in height instead of 6 inches.
FIG. 10 is a cross-sectional view of connection mechanism 214 , which is another alternative embodiment of a connection mechanism in accordance with the present invention. Connection mechanism 214 further includes first and second flange encasement members 216 and 218 encasing first and second flange members 56 and 58 , respectively. First and second flange encasement members 216 and 218 may be integral with and extend from first and second arms 52 and 54 of connection mechanism 214 .
In the illustrated embodiment, first and second flange encasement members 216 and 218 may be formed from a concrete material that is the same or similar to the concrete material used to form main body 30 and first and second arms 32 and 34 of connection mechanism 214 . Thus, connection mechanism 214 may be preferred over connection mechanism 14 when it is desirable to have a concrete-to-concrete connection between the connection mechanism and the retaining wall block to which it will be affixed.
Referring now to FIG. 11 , yet another alternative embodiment is illustrated. More specifically, FIG. 11 illustrates a more angled connection mechanism 314 which is specifically configured to more evenly distribute stress. In this particular embodiment, connection member 314 has a first leg 332 and a second leg 334 , both of which are arranged in an angled orientation. Additionally, a slightly reconfigured reinforcing member 348 is utilized. As can be seen, reinforcing member 348 includes two angles or bends B at the corners. When compared with reinforcing member 48 of FIG. 4 above, it will be clear that these angles are greatly reduced, thus more evenly distributing pulling forces.
In a similar manner, yet an additional alternative embodiment for a connection mechanism 414 is illustrated at FIG. 12 . In this particular embodiment, a revised reinforcement member 448 is utilized which is continuously curved. This particular configuration allows for the use of alternative materials, such as a carbon fiber material or fiberglass reinforced plastic. Naturally, using these alternative materials for reinforcing mechanism 448 provides alternative weight/strength combinations, as desired. As illustrated in this FIG. 12 , the body of connection mechanism 414 is otherwise substantially similarly configured as connection mechanism 314 illustrated in FIG. 11 above.
Lastly, referring to FIG. 13 , yet a further alternative embodiment is illustrated. In this case, a connection mechanism 514 is shown again utilizing a continuously curved reinforcing member 548 . In this embodiment, however, reinforcing member 548 is completely encased in concrete. Connection mechanism 514 does include a first leg 532 and a second leg 534 , both of which encase the ends of reinforcement mechanism 548 . As also illustrated, first leg 532 and second leg 534 of connection mechanism 514 are angled outwardly from top to bottom (as oriented in FIG. 13 ). This angled structure allows connection mechanism 514 to be immersed in concrete when utilized to form a retaining wall block. Due to the angles or flares of first leg 532 and second leg 534 , a mechanical connection can be formed thereby providing secure attachment. This type of immersed attachment methodology is very similar to that discussed above in relation to FIG. 10 .
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. | A block assembly includes integral connection mechanisms specifically designed for incorporation into engineered retaining walls. These connection mechanisms specifically accommodate the use of reinforcing grids in the formation of a retaining wall which, when used, will stabilize the retaining wall and provide additional strength. The connection mechanism is formed prior to fabrication of the block itself, and thus can be integrally incorporated during casting/fabrication of the block itself. The connection mechanism defines a connection slot usable during retaining wall fabrication (by allowing easy connection to the reinforcing grid) while also accommodating holding and lifting of the block assembly. Due to the fabrication method, the configuration of the connection mechanisms inserted into the block can be uniquely designed to provide desired physical coupling once the concrete is hardened. This further allows the use of different materials and different structures to provide the desired strength and allow the use of optimal materials. | 4 |
PRIORITY CLAIM AND RELATED PATENT APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application No. 60/896,859 entitled “SCALABLE OFDM AND OFDMA BANDWIDTH ALLOCATION IN COMMUNICATION SYSTEMS” and filed on Mar. 23, 2007, which is incorporated by reference as part of the specification of this application.
BACKGROUND
[0002] This applications relates to wired and wireless communications including communications based on, among others, OFDM (Orthogonal Frequency Division Multiplexing), OFDMA (Orthogonal Frequency Division Multiple Access), and SC-FDMA (Single Carrier Frequency-Division Multiple Access) systems.
[0003] In various wireless cellular networks, communication capacity and data throughput may be degraded due to unavailable or congested network spectrum. Allocated spectral bands are becoming increasingly congested with desired and undesired signals due to the proliferation of both intentional and unintentional electromagnetic emissions. Such a congested spectrum can lead to signal degradation and interferences. For example, both low and high power signals may be simultaneously observed by a receiver's antenna or antenna array. Under such conditions, desired signals may be obscured and undetectable since they can be buried beneath much stronger clusters of interfering signals.
[0004] Among the different technologies that can make use of the spectrum, Orthogonal Frequency Division Multiplexing (OFDM) is a technique for multicarrier data transmission that has been standardized for several wireless network physical layers. In OFDM, an allocated channel is divided into a number of orthogonal subchannels. Each subchannel has an equal bandwidth and is made of a unique group of subcarrier signals. The subcarrier signals are orthogonal in that the inner product of any two of the subcarriers equals zero. The frequencies of the orthogonal subcarrier signals are equally and minimally spaced so data modulation of the subcarrier signals facilitates optimal bandwidth efficiency. In comparison, frequency division multiplexing for multicarrier data transmission utilizes non-orthogonal subcarrier signals and uses segments of allocated channel bandwidth to isolate subcarrier signal frequency spectra.
[0005] Orthogonal Frequency Division Multiple Access (OFDMA) is a multi-user version of OFDM technology. The multiple access is achieved in OFDMA by assigning subsets of orthogonal subcarriers to individual subscriber stations. OFDMA may be viewed as a combination of frequency domain and time domain multiple access where radio resources are partitioned in a time-frequency space, and network user data bursts are assigned along the OFDM symbol index as well as OFDM sub-carrier index. OFDMA has been widely adopted by various standard bodies.
[0006] The Single Carrier Frequency Division Multiple Access (SC-FDMA) can be viewed as either a linearly precoded OFDMA scheme, or a single carrier multiple access scheme. One advantage of SC-FDMA over a conventional OFDMA is that the SC-FDMA signal has lower peak-to-average power ratio (PAPR) because of its inherent single carrier modulation method. The SC-FDMA can also be considered as an alternative to OFDMA, especially for the uplink communications where lower PAPR benefits the mobile terminal power efficiency. SC-FDMA has been adopted for uplink multiple access scheme in 3GPP Long Term Evolution (LTE), or Evolved UTRA.
[0007] In the frequency domain, an OFDM or OFDMA signal is made up of orthogonal subcarriers, the number of which determines the size of the Fast Fourier Transform (FFT), N FFT . FIG. 1A illustrates the OFDMA bandwidth definition. Assuming Δf is the subcarrier spacing, the sampling frequency f S can be calculated with the formula:
[0000]
f
S
=Δf×N
FFT
[0000] For a given nominal channel bandwidth BW, only a subset of subcarriers N SIG out of N FFT is occupied for signals, referred as signal bandwidth BW SIG . N SIG may include DC sub-carrier which often contains no data. The rest of the subcarriers which are not used for transmission of data and information serve as guard subcarriers. The guard subcarriers are used to enable the signal to naturally decay and create the FFT “brick wall” shaping. The rule of thumb to select the FFT size is to choose the smallest power of two that is greater than N SIG . As illustrated, the normal channel bandwidth BW is greater than the signal bandwidth due to the presence of the guard subcarriers on both sides of the signal-carrying subcarriers. The sampling frequency fs is selected to be greater than the normal channel bandwidth.
[0008] In the OFDMA physical layer, the resource grid and basic resource block are defined. Based on the defined resource grid, one or multiple basic blocks in a group in the frequency domain are defined as a subchannel in some standards. N SIG may contain multiple subchannels or basic resource blocks, each consists of N SC subcarriers. The subchannel is used as the minimum channel bandwidth division unit in this document and each subchannel has N SC subcarriers.
[0009] The Inverse Fast Fourier Transform (IFFT) creates an OFDM or OFDMA waveform and the associated time duration is referred to as the useful symbol time T IFFT . FIG. 1B illustrates the time domain symbol structure of an OFDM or OFDMA signal. A copy of the last of the useful symbol period is known as the Cyclic Prefix (CP) T G and is used to collect multipath, while maintaining the orthogonality of the tones. In addition, a small windowing period can be optionally added to a time slot before the CP and a time slot at the end of a symbol time. Adding windowing periods can reduce the signal in-band emission and the signal out-of-band emission. The total symbol time T SYM includes the additional CP time T G , and optional windowing time T WIN , T SYM =T G +T IFFT +T WIN . Using a cyclic extension, the samples required for performing the FFT at the receiver can be taken anywhere over the length of the extended symbol. This provides the multipath immunity as well as a tolerance for symbol time synchronization errors.
SUMMARY
[0010] This application describes, among others, OFDM (Orthogonal Frequency Division Multiplexing), OFDMA (Orthogonal Frequency Division Multiple Access), and SC-FDMA (Single Carrier Frequency-Division Multiple Access) bandwidth allocation techniques to reduce and, in some cases, eliminate guard subcarriers. In various implementations, the described techniques can be used to enhance the spectral efficiency of the usage of spectrum.
[0011] In one aspect, a method for allocating spectral bandwidth for an Orthogonal Frequency Division Multiplexing (OFDM) or Orthogonal Frequency Division Multiple Access (OFDMA) system is described to include: choosing a common subcarrier spacing for orthogonal subcarriers; selecting a sampling frequency that is equal to or greater than a given nominal channel bandwidth of a carrier; and using subcarriers within the given nominal channel bandwidth for signal transmission without assigning subcarriers as guard subcarriers at both ends of the given nominal channel bandwidth of the carrier.
[0012] In another aspect, a method for spectral bandwidth allocation for an Orthogonal Frequency Division Multiplexing (OFDM) and Orthogonal Frequency Division Multiple Access (OFDMA) system is described to include allocating multiple different nominal channels to be sequentially next to one another in frequency without guard bands in between; assigning all subcarriers in the multiple different nominal channels to have a common subcarrier spacing between two adjacent subcarriers and to be aligned across the multiple different nominal channels; selecting a sampling frequency that is equal to or greater than a given nominal channel bandwidth or multiple nominal channel bandwidths; and using subcarriers within a given nominal channel bandwidth or multiple channel bandwidths for signal transmission without assigning subcarriers as guard subcarriers at both ends of the nominal channel bandwidth for each of the multiple different nominal channels.
[0013] In another aspect, a method for allocating spectral bandwidth for an Orthogonal Frequency Division Multiplexing (OFDM), Orthogonal Frequency Division Multiple Access (OFDMA) system, or Single Carrier Frequency-Division Multiple Access (SC-FDMA) includes dividing a frequency band into a plurality of channels with normal channel bandwidths; dividing each channel into a plurality of subchannels each comprising a plurality of subcarriers; and selecting the nominal channel bandwidths so that each nominal channel bandwidth is evenly divided into a plurality of subchannels.
[0014] In yet another aspect, a method for allocating spectral bandwidth for an Orthogonal Frequency Division Multiplexing (OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), or Single Carrier Frequency-Division Multiple Access (SC-FDMA) system includes choosing a carrier distance between two neighboring carriers in deployment so that edge subcarriers belonging to two different carriers are orthogonal to each other to reduce or eliminate inter-carrier interference.
[0015] In yet another aspect, a method for allocating spectral bandwidth for an Orthogonal Frequency Division Multiplexing (OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), or Single Carrier Frequency-Division Multiple Access (SC-FDMA) system includes choosing a common subcarrier spacing of orthogonal subcarriers to evenly divide a given nominal carrier bandwidth.
[0016] In yet another aspect, a method for allocating spectral bandwidth for an Orthogonal Frequency Division Multiplexing (OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), or Single Carrier Frequency-Division Multiple Access (SC-FDMA) system includes choosing a common subcarrier spacing of orthogonal subcarriers that can divide multiple nominal channel bandwidths evenly in a multi-carrier system.
[0017] These and other examples and implementations are described in greater detail in the attached drawings, the detailed description and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIGS. 1A , and 1 B show an exemplary OFDM or OFDMA signal definition in frequency domain and time domain respectively.
[0019] FIG. 2A illustrates, even for the typical same OFDM technology deployment, the carrier distance between the two neighboring OFDM systems can not be divided evenly by the subcarrier spacing, subcarrier spacing can not be maintained across the boundary of the two carriers, which will cause strong inter-carrier interference to each other at the edge subcarriers.
[0020] FIG. 2B illustrates the guard subcarriers (without signal transmission) and filtering are used to reduce the inter-carrier interference described in FIG. 2A .
[0021] FIG. 3A shows an exemplary OFDM or OFDMA signal where the nominal carrier bandwidth is divided evenly by the subcarrier spacing. No guard subcarriers are needed in some applications or deployment.
[0022] FIG. 3B shows an exemplary multi-carrier OFDM or OFDMA deployment, where no guard subcarriers are necessary among the three carriers and all subcarriers are orthogonal to each other.
[0023] FIG. 3C shows an example of how a multi-carrier signal is generated. In the example a three carriers of 10 MHz are used and the number of subcarriers is not accurate, and is solely for illustration purpose. Applying the methods of this invention, the three 10 MHz carriers can be deployed side-by-side without guard bands in between.
[0024] FIG. 4A illustrates variation of examples of multi-carrier scalable OFDM or OFDMA bandwidth allocation.
[0025] FIG. 4B illustrates possible option not to transmit at the edge subcarriers in order to meet the spectral mask requirements in some deployment.
[0026] FIG. 5A illustrate an example of scalable multi-carrier OFDM or OFDMA network which includes a base station, a relay station, and 5 subscriber stations.
[0027] FIG. 5B showcases a multiple-carrier scalable OFDM and OFDMA hybrid bandwidth allocation scheme, where the relay station (RS) also supports mixed multi-carrier deployment. The carrier channel bandwidth in deployment can be divided into multiple of different smaller carrier channel bandwidths. Each channel bandwidth is capable of support its class of subscriber stations independently, including initial synchronization process.
[0028] FIG. 6A illustrate an example of scalable multi-carrier OFDM, OFDMA, or SC-FDMA network, in which a 40 MHz carrier channel bandwidth can be divided into multiple of 20 MHz, 10 Mhz, and 5 MHz carrier channel bandwidths.
[0029] FIG. 6B illustrates a dynamic multi-carrier deployment where different multi-carrier channel bandwidths are supported dynamically in time.
[0030] FIG. 6C illustrates an example of how a 10 MHz carrier bandwidth can be split into two 5 MHz carrier channel in the deployment.
[0031] FIGS. 7A and 7B illustrate an multi-carrier deployment example of 3×10 MHz channel bandwidth.
DETAILED DESCRIPTION
[0032] Various communication systems define an OFDM, OFDMA or SC-FDMA symbol structure to include guard subcarriers to enable the signal to naturally decay and create the FFT “brick Wall” shaping in order to reduce undesired interferences between neighboring channels. Examples include communication systems based on IEEE 802.16 or WiMAX, Ultra Mobile Broadband (UMB), and Long Term Evolution (LTE) systems.
[0033] The symbol structures in various OFDM or OFDMA systems with guard subcarriers can lead to variations in the subcarrier spacing. Therefore, the orthogonality of two adjacent subcarriers is no longer preserved and this condition causes intersymbole interference between adjacent symbols.
[0034] FIG. 2A shows an example where, in the same OFDM technology deployment, the carrier distance between the two neighboring OFDM systems cannot be divided evenly by the subcarrier spacing and the subcarrier spacing can not be maintained at a constant across the boundary of the two carriers. This variation in the subcarrier spacing causes strong inter-carrier interference to each other at the edge subcarriers.
[0035] FIG. 2B illustrates an example of typical multi-carrier OFDM or OFDMA bandwidth allocation with the guard subcarriers. The guard subcarriers occupy frequency bands without transmitting useful signals and information. Signal filtering by baseband filters is used to reduce the inter-carrier interference. Such guard bands are also commonly used by other technologies. Although useful for reducing undesired signal interference, the presence of such guard bands reduces the available subcarriers for transmitting data and information within the normal signal bandwidth and thus reduces the utilization of the precious spectral real estate in allocated frequency bands.
[0036] This application includes, among others, examples and implementations of methods and apparatus for allocating signal bandwidth and subcarrier frequencies with a constant subcarrier frequency spacing to reduce or eliminate unnecessary guard bands in the spectral bandwidth allocation in wireless communication systems, such as OFDM and OFDMA systems. The guard bands between different carriers can be eliminated and to increase the spectral efficiency of overall spectrum. In most of the OFDM and OFDMA standard technologies developed, the subcarrier spacing can not divide a nominal RF carrier bandwidth evenly, which results in an irregular number of available subcarriers for resource planning. By selecting a minimum size of resource block, the edge subcarriers become un-useable for data transmission, and they are often called guard subcarriers. The frequency efficiency is often reduced due to the presence of un-necessary guard subcarrier.
[0037] The numerology based on a typical legacy 16e design can be found in IEEE 802.15e 2005 . The subcarrier spacing for 10 MHz nominal carrier bandwidth is defined to 10.9375 kHz. Out of 914 subcarriers that fall into the 10 MHz bandwidth, there are only 840 subcarriers that can be used to transmit information; the rest edge subcarriers become guard subcarriers which are not used for transmit signals; about 8.8% of the bandwidth is wasted. If the guard subcarriers can be utilized for data transmission, the frequency efficiency can be 8.8% more efficient.
[0038] The maximum frequency efficiency can be computed by the following equation:
[0000]
n
Efficiency
=
R
Modulation
×
n
UsedSubcarriers
T
symobol
×
BW
System
(
Eq
.
1
)
[0000] where R Modulation is modulation rate (e.g. 4 for 16QAM), n UsedSubcarriers is number of used subcarriers within the nominal system bandwidth, T symbol is symbol period, and BW System is the nominal system bandwidth. Let's set CP=0 to calculate the maximum n Efficiency of the system
[0000]
T
symobol
=
1
Δ
f
(
Eq
.
2
)
[0000] where Δf is subcarrier spacing.
[0000] BW system ≧n MaximumSubcarriers ×Δf (Eq. 3)
[0000] where n MaximumSubcarriers is the maximum number of subcarriers that a nominal system bandwidth can have.
Substitution of Eq. 2, and Eq. 3 into Eq. 1 yields the following:
[0000]
n
Efficiency
≤
R
Modulation
×
n
UsedSubcarriers
n
MaximumSubcarriers
(
Eq
.
4
)
[0000] Therefore, the frequency efficiency is proportional to the number of used subcarriers over the maximum number of subcarriers within the carrier nominal bandwidth.
Under the UMB (Ultra Mobile Broadband) of 3GPP2 (3 rd Generation Partnership Project 2) standard, the subcarrier spacing is 9.6 kHz and cannot be divided evenly by nominal carrier bandwidths such as 1.25 MHz, 2.5 MHz, 5 MHz, 10 MHz, or 20 MHz. As a result, some of the edge subcarriers are left as guard subcarriers with no signal transmission. This condition results in a lower spectrum usage or spectral efficiency. Under the LTE (Long Term Evolution) of 3GPP2 (3 rd Generation Partnership Project) standard, the subcarrier spacing is 15 kHz or 7.5 KHz and cannot be divided evenly by nominal carrier bandwidths such as 1.25 MHz, 2.5 MHz, 5 MHz, 10 MHz, or 20 MHz. Some of the edge subcarriers are left as guard subcarriers with no signal transmission. Similar to the UMB, this condition in LTE leads to a lower spectrum usage or spectral efficiency.
[0040] One method to reduce or eliminate guard bands is to choose a common subcarrier spacing (Δf) of orthogonal subcarriers that can evenly divide a carrier distance of two neighboring carriers. This technique can reduce the interference caused by the two neighboring carriers when the carrier distance cannot be divided evenly by the subcarrier spacing as shown in FIG. 2A .
[0041] One implementation of the above method is to choose a common subcarrier spacing (Δf) of orthogonal subcarriers that can evenly divide a given nominal channel bandwidth. Subcarrier spacings (Δf) of 12.5 KHz and 10 KHz are given in Table 1 and Table 2 respectively as implementation examples of OFDMA systems. In Table 1, subcarrier spacing (Δf) of 12.5 KHz can divide all nominal carrier bandwidths. The number of used subcarriers for each carrier bandwidth can be calculated and shown in Table 1. Similarly subcarrier spacing (Δf) of 10 KHz can evenly divide all nominal carrier bandwidths. The number of used subcarriers for each carrier bandwidth can be calculated and shown in Table 2.
[0000]
Parameter
Unit
Parameter Values
Channel Bandwidth
MHz
5
6
7
8.75
10
12
14
20
40
(BW)
Sub-carrier Spacing
KHz
12.5
(Δf)
Sampling Frequency
Mhz
6.4
6.4
12.8
12.8
12.8
12.8
25.6
25.6
51.2
(Fs)
FFT size
512
512
1024
1024
1024
1024
2048
2048
4096
Number of Used sub-
400
480
560
700
800
960
1120
1600
3200
carriers (Nused)
Num of Sub-carriers
20
Per Sub-channel
Sub-channel
KHz
250
Bandwidth
Number of Sub-
20
24
28
35
40
48
56
80
160
channels
Num of Guard Sub-
0, or up to 4
channels (L or R)
[0042] Table 1 illustrates the exemplar subcarrier spacing of 12.5 KHz and a subchannel of 20 subcarriers. Alternatively, a subchannel of 16 subcarriers can also be used for system deployment.
[0000]
Parameter
Unit
Parameter Values
Channel Bandwidth
MHz
5
6
7
10
12
14
20
40
(BW)
Sub-carrier Spacing
KHz
10
(Δf)
Sampling Frequency
Mhz
5.12
10.24
10.24
10.24
20.48
20.48
20.48
40.96
(Fs)
FFT size
512
1024
1024
1024
2048
2048
2048
4096
Number of Used sub-
500
480
700
1000
960
1400
2000
4000
carriers (Nused)
Num of Sub-carriers
20
Per Sub-channel
Sub-channel
KHz
200
Bandwidth
Number of Sub-
25
30
35
50
60
70
100
200
channels
Num of Guard Sub-
0, or up to 5
channels (L or R)
[0043] In a typical OFDM or OFDMA deployment, the neighboring radio frequency (RF) carriers are also used for the same or similar OFDMA technologies. Therefore, multiple RF carriers can be placed so that the interference between neighboring RF carriers can be reduced to the minimum. In one implementation, a subcarrier spacing can evenly divide all nominal carrier bandwidths, exemplary subcarrier spacings, such as 12.5 KHz and 10 KHz, are shown in Table 1 and Table 2. In another OFDM, OFDMA, or SC-FDMA implementation, no guard subcarriers are needed within a given nominal channel bandwidth. The out of band emission is orthogonal to neighboring OFDM or OFDMA subcarriers or simply removed by digital and/or RF filters.
[0044] FIG. 3A illustrates that the signal bandwidth can be equal to the nominal channel bandwidth in one implementation. The spectral efficiency can be improved without wasting spectrum bandwidth on unnecessary guard subcarriers.
[0045] In another OFDM, OFDMA, or SC-FDMA implementation, multiple OFDM or OFDMA channels can be placed one next to each other provided the subcarrier spacing of all channels is uniformed, and all subcarriers are aligned among channels. The spectral efficiency can be improved without wasting spectrum bandwidth on unnecessary guard subcarriers between two neighboring channels.
[0046] FIG. 3B illustrates an exemplary multi-carrier OFDM or OFDMA bandwidth allocation. In the figure, subcarrier spacing remains the same and frequency aligned across the bandwidth boundaries of two neighboring carriers indicated by nominal bandwidths allocation. Since all the subcarriers are orthogonal to each other, the interference to neighboring RF carriers is reduced to minimum.
[0047] In another implementation, a subcarrier spacing can not only evenly divide all nominal carrier bandwidths, it can also divide a channel raster, such as 250 KHz, of a particular RF frequency band. The common subcarrier spacing of orthogonal subcarriers can be frequency aligned between boundaries of all adjacent carrier bandwidth allocations in the said RF frequency band to reduce or eliminate inter-carrier interference. The example of such implementation is illustrated in FIG. 3C . This implementation is particular important when the OFDM, OFDMA, or SC-FDMA system is designed to support multi-carrier.
[0048] In one implementation, a subcarrier spacing evenly divides all nominal carrier bandwidths and also divides multiple channel rasters, such as 250 KHz and 200 KHz, of different RF frequency bands. The common subcarrier spacing of orthogonal subcarriers can be frequency aligned between boundaries of all adjacent carrier bandwidth allocations in each of multiple RF frequency bands to reduce or eliminate inter-carrier interference within the said RF frequency band. This implementation is particular important when the OFDM, OFDMA, or SC-FDMA system is designed to support multi-carrier and global roaming.
[0049] In another implementation, the multi-carrier system bandwidth can be made of different-size nominal bandwidths. FIG. 4A illustrates an exemplary application of multiple carriers with non-uniformed bandwidths. As long as the base stations are frequency synchronized, the subcarriers remain orthogonal to each other. No guard subcarriers are necessary.
[0050] FIG. 4B illustrates an exemplary application of multi-carrier with edge guard carrier so that they will co-exist with other technologies.
[0051] In another OFDM or OFDMA implementation, the downlink and uplink bandwidths can be different. The downlink from a base station can be a multi-carrier system, and the uplink from a relay station (RS) subscriber station (SS) (a fixed, nomadic, or mobile station) can be working on only one or some of the nominal channel bandwidths. FIG. 5A shows an exemplary multiple access network. FIG. 5B illustrates the hybrid bandwidth allocation scenario among the base station and subscriber stations. In the illustration, the base station can simultaneously support multiple subscriber stations with different access carrier bandwidth. In the same illustration, the relay station can also simultaneously support multiple subscriber stations with different access carrier bandwidths.
[0052] This feature can be applicable to both FDD and TDD modes. This is different from the traditional hybrid deployment in FDD mode, where a downlink channel has a different (usually larger) bandwidth than a paired uplink channel. Both the base station and subscriber station have to utilize the downlink and uplink bandwidths, and it is usually not applied in the TDD mode.
[0053] In one implementation, communication systems described in this application can operate using Orthogonal Frequency Division Multiplexing (OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Frequency Division Duplexing (FDD), and Time Division Duplexing (TDD). These technologies described within this subsection are applicable to both wireline and wireless implementations.
[0054] Multiple OFDM or OFDMA channels can be transmitted from the same or different base stations. As long as the base stations are frequency synchronized, the subcarriers remain orthogonal to each other. No guard subcarriers are needed. This application is applicable to both FDD and TDD modes. This application is applicable to a relay station.
[0055] In another OFDM or OFDMA implementation, multiple OFDM, OFDMA, SC-FDMA carriers can be transmitted from the same or different base stations.
[0056] FIG. 6A illustrate an example of scalable multi-carrier OFDM, OFDMA, or SC-FDMA network, in which a 40 MHz carrier channel bandwidth can be divided into multiple of 20 MHz, 10 Mhz, and 5 MHz carrier channel bandwidths. When a subcarrier spacing is properly chosen, say 12.5 KHz or 10 KHz, each smaller carrier channel bandwidth is frequency aligned with the frequency band RF channel raster locations, so that the subscriber stations can potentially associate with the smaller carriers, say 5 MHz, 10 Mhz, or 20 MHz channels, independently without decoding the full 40 MHz bandwidth.
[0057] FIG. 6B illustrates a dynamic multi-carrier deployment where different multi-carrier channel bandwidths are supported dynamically in time. In the example, 5 MHz, 6 MHz, 7 MHz, 10 MHz, 12 Mhz, 14 MHz, 20 MHz can be supported simultaneously by the multi-carrier system in the deployment.
[0058] FIG. 6C illustrates an example of how a 10 MHz carrier bandwidth can be split into two 5 MHz carrier channel in the deployment. A subchannel of 20 subcarriers is used to explain how a subchannel can be properly defined to support multi-carrier deployment.
[0059] FIGS. 7A and 7B illustrate an multi-carrier deployment example of 3×10 MHz channel bandwidth. In FIG. 7A , No guard subchannels are required to meet spectral mask requirements. In FIG. 7B , The edge subchannels are assigned as guard subchannels which are not used for transmitting signals in order to meet the spectral mask requirements. When Subcarrier spacing is 12.5 KHz, and a subchannel consists of 20 subcarriers, a subchannel bandwidth is 250 KHz, multiple subchannels (250 KHz each) can be used for guard subchannels.
[0060] While this specification contains many specifics, these should not be construed as limitations on the scope of any invention or of what may be claimed, but rather as descriptions of features specific to particular embodiments. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination. Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results.
[0061] Only a few implementations and examples are described, variations and enhancements of the described implementations and examples, and other implementations are possible based on what is described. Other embodiments are within the scope of the following claims. | Techniques for bandwidth allocation in communication systems such as OFDM, OFDMA, or SC-FDMA systems to improve spectral efficiency and increase flexibility and adaptability with scalable single or multiple-carrier bandwidth allocation characteristics. | 7 |
BACKGROUND
The present invention relates to an apparatus for facilitating operator use of a wheelchair in a sanitary manner that inhibits the transfer of contaminants from the wheel to the user and also prevents the buildup of such contaminants on the wheel surface.
Certain governmental agencies, such as the Occupational Safety and Health Administration (OSHA), the Center for Disease Control and Prevention (CDC) and similar state agencies and authorities issue and enforce standards for minimizing contamination of appliances, articles and various other devices that are touched and used by residents and/or patients in hospitals, assisted living facilities, and nursing homes. Responsible agencies, authorities and administrations promulgate, monitor and enforce regulations to inhibit the propagation of contaminants on appliances that may carry bacteria, viruses and other disease carrying contaminants. Rules and regulations to minimize the transfer of such diseases address all types of apparatus and appliances that are routinely touched by patients, residents, healthcare providers and other workers.
One device that is particularly problematic and well known to be the source of many kinds of contaminants is the ubiquitous wheelchair found and used in all the aforementioned facilities. A conventional wheelchair has two main large diameter rear wheels to which are attached concentric smaller diameter push or drive wheels. The user grasps the smaller diameter concentric wheel to drive the wheelchair and to avoid user contact with the large diameter floor-engaging rear wheels. Regulations typically require periodic cleaning of the main rear wheels, but, as is apparent, freshly cleaned rear wheels will quickly become contaminated. A user utilizing the push ring oftentimes contacts the large diameter wheel with the user's wrists as the push wheel is propelled by the user.
SUMMARY
The present invention provides a sanitary wheel cover and a drive grip that permits the user to drive the wheelchair by the large floor-engaging rear wheel without direct contact therewith. The drive grip can be grasped by the user and flexed to compress a compressible portion against a portion of the outer rim of the main wheel to alternately propel the wheelchair in a forward direction (or similarly the rear direction) and then release the grip for return to a neutral position under the influence of an elastic strap that connects each end of the drive grip for the respective front and rear of the wheelchair frame. The apparatus of the present invention may be used without the need for a conventional push rim because the user's hands grasp the drive grip and large wheel to provide propulsion.
The sanitary wheelchair cover and drive grip of the present invention is intended primarily for use on a wheelchair of the type that has a user supporting frame, a pair of large diameter rear wheels carried on the frame and engageable by the user to propel the chair. The apparatus of the present invention facilitates user propulsion without contamination of the user's hands from material picked up in use and carried on the outer surface of the rear wheels.
A semi-circumferential drive grip 19 is demountably attached to a tire on the large outer rim of each rear wheel. The drive grip includes a manually compressible portion that is in direct contact with the outer rim and a flexible grip cover that overlies the compressible portion of the grip. An elastic strip connects each end of the drive grip to the respective front and rear of the wheelchair frame to hold the grip in a neutral position. The user is able to grasp the grip and compress the compressible portion against the tire on the outer rim and push the main drive wheel forwardly. This movement increases the length of and tension in the rear strap and provides rolling movement of the wheel. Releasing the grip by the user reduces the compression to permit higher tension in the rear strap to return the grip to the neutral position. Rearward movement of the wheelchair is accomplished in a similar manner.
The manually compressible portion of the drive grip preferably comprises a tubular piece of polymeric foam that is curved to adapt the tubular piece to the curvature of the wheel. The flexible grip cover preferably comprises a U-shaped plastic piece that overlies the tubular foam piece. In one embodiment, the U-shaped plastic piece is fastened to the tubular foam piece. The plastic piece may be fastened to the tubular piece with an adhesive, a hook-and-loop fastener, or some other suitable connecting device.
The radially outer surface of the flexible plastic piece preferably has an outer grip-enhancing texture or similar surface treatment. The elastic strip extends through slots in the respective front and rear ends of the grip cover. The elastic straps may comprise separate straps, but, preferably, the elastic straps are one-piece. Each elastic strip is demountably attached at opposite strap ends to the wheelchair frame.
The interior surface of the tubular foam piece may be provided with one or more layers or coating of a material that is selected from the group consisting of a lubricant, a cleaner and a biocide. The lubricant coating facilitates sliding movement of the tubular piece relative to the wheel rim when not being compressed and propelled. The coating of a cleaner and/or a biostatic provides protection against contamination of the user's hands and anyone or anything else that might come into contact with a user. The tubular foam piece may be detachable from the grip cover for disposal and replacement. Preferably, the tubular foam piece is cut from a spirally wound supply to more easily adapt to the curvature of the wheelchair drive wheels. Further, the tubular foam piece is preferably formed with a slit along its length providing a C-shaped tubular piece having oppositely facing lengthwise edges. If the foam piece is not pre-formed with a curvature, the lengthwise edges of the C-shaped tubular piece can be provided with V-shaped slots to accommodate bending of a straight tubular piece to the desired curved shape.
In a related method for facilitating sanitary use and propulsion of a wheelchair by a user, the wheelchair having a frame and a pair of large diameter rear wheels carried on the frame and engageable for propulsion by the user, the method comprises the steps of (1) mounting a semi-circumferential drive grip to an outer portion of a tire on the rim of each rear wheel, (2) providing the drive grip with a tubular piece of polymeric foam in contact with the tire on the wheel outer rim, (3) providing the drive grip with a flexible grip cover that overlies the compressible tubular foam piece, (4) attaching the grip cover to the tubular foam piece, and (5) connecting the opposite circumferential ends of the drive grip to the front and rear of the wheelchair frame with respective front and rear elastic members, whereby the drive grip is initially held in a static neutral position by the elastic members. Manual engagement of the drive grip with squeezing and pushing action by the user causes the compressible tubular foam piece to clamp the wheel, and causes the wheel and chair to move forwardly without direct contacting touch of the wheel by the user.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a prior art wheelchair to which is attached the sanitary wheel cover and drive grip of the present invention.
FIG. 2 is an enlarged side elevation view of the sanitary wheel cover and drive grip of the present invention.
FIG. 3 is a bottom plan view of the cover and drive grip shown in FIG. 2 .
FIG. 4 is an isometric sectional view taken on line 4 - 4 of FIG. 3 .
FIG. 5 is an enlarged detail taken on line 5 - 5 of FIG. 4 .
DETAILED DESCRIPTION
In FIG. 1 , there is shown a conventional wheelchair 10 having a general construction well known in the art. A frame 11 provides support for the seated user and includes front and rear frame members 12 and 13 that are interconnected with side frame members 14 and 15 . The front frame member includes a connection at the lower end to a pair of castered support wheels 16 . A pair of large diameter drive wheels 17 and 18 are carried by the side frame members 14 and 15 . To support the user, flexible cloth or cloth-like panels are attached to the frame 11 and include a seat panel 21 , a pair of side panels 22 , and a pair of generally vertically aligned back panels 23 , all in a manner well known in the art. The upper ends of the rear frame member 13 includes push arms 24 to provide assistance to the user and a pair of front foot supports 25 that are typically pivotable to swing away or are completely detachable.
In FIG. 1 , the sanitary wheel cover and grip 19 of the present invention is shown attached to the wheelchair W and, in FIGS. 2 and 3 , the sanitary wheel cover and grip 19 is shown enlarged and detached from the wheelchair W. The cover and grip 19 includes a tubular semi-circumferential piece of polymeric foam 26 that, in use, is attached to a tire 29 on the rim 27 of the drive wheel 17 , 18 . The tubular foam piece 26 has a longitudinal slit 28 that defines oppositely facing lengthwise edges 30 . The slit 28 facilitates attachment of the cover and grip 19 to the rims and tires 29 of the drive wheels 17 , 18 , and also adapts the device to varying rim sizes.
The polymeric foam from which the tubular piece is made may vary considerably, but a closed cell polyurethane foam has been found to be suitable. Other foam materials of both open and closed cell construction may also be used.
A flexible grip cover 31 overlies and partially covers the tubular foam piece 26 . The grip cover may be formed to the curvature of the drive wheels 17 and 18 or may be sufficiently flexible to bend to the desired curvature. Any relatively hard, but flexible plastic may be used. However, if the tubular foam piece is cut from straight tubular stock, the tubular pieces may be formed with V-shaped slots 32 spaced along the edges 30 of the longitudinal slit 28 . The flexible grip cover 31 is preferably of a generally U-shape and has an outer grip-enhancing texture 33 or similar surface treatment to minimize slippage of the user's hands on the cover.
Although the grip cover 31 may be adhesively attached to the tubular foam piece to provide a desired permanent connection, allowing the integral cover 31 and foam piece 26 to be disposable, the foam piece 26 may be removable or demountable for replacement. If the foam piece is intended to be removable from the grip cover 31 , the pieces may be fastened together with an easily removable adhesive, a hook-and-loop fastener, or some other suitable connecting device.
An elastic strip 34 connects each end of the grip cover 31 to a front frame member 12 and a rear frame member 13 . The elastic strip 34 may comprise a single piece of elastic or two separate strip pieces. In the embodiment shown, the elastic strip 34 is unitary. The strip is attached to the grip cover 31 by running opposite ends of the strip through front and rear strip slits 35 in the cover where the center of the elastic strip may be held in place with the same adhesive used to attach the grip cover 31 to the tubular foam piece 26 . The opposite front and rear free ends of the elastic strip 34 may be conveniently wrapped around any suitable portion of the side frame members 14 and 15 , stretched to provide tension in the strip, and brought back on itself and fixed in position with a hook-and-loop fastener 36 . With both ends of the elastic strip 34 attached and tensioned as indicated, the drive grip 19 is held in a neutral position as shown in FIG. 1 .
When a user seated on the wheelchair 10 grasps the grip cover 31 of the drive grip 19 , the grip is easily slid along the tire 29 and rim 27 of the drive wheel 17 , but if the user squeezes the drive grip, a gripping force is applied to the tire and rim to cause the wheelchair to be propelled forwardly. The forward movement of the drive grip simultaneously causes the front end of the elastic strip 34 to contract and to decrease the tension therein. At the end of forward movement of the drive grip, the user releases the compression and the rear end of the elastic strip 34 , having been lengthened and further tensioned by the drive grip, will cause the drive grip to slide rearwardly to the neutral position of the grip.
If necessary, the ID of the tubular foam piece 26 may be lubricated by applying a thin coating of a suitable lubricant thereto. In addition, the ID of the foam piece 26 may also be provided with a biostatic coating and/or a suitable cleaner. In this manner, the sanitary wheel cover and drive grip 19 of the present invention minimizes user contact with the tires 29 and rims 27 , helps keep the device clean and may provide a suitable decontaminant. The conventional wheelchair push wheels or rims may be eliminated. | A wheelchair propulsion and contamination reduction arrangement permits the user to drive the chair on the main ground-engaging rear wheels with a compressible wheel cover that is grasped and squeezed against the wheel to provide propulsion and mounted with elastic tension devices on opposite ends that return the drive grip to a neutral position when the user relaxes the compression. The compressible device is a polymeric foam which can also be adapted to carry one or more of a lubricant, cleaner and biostatic treatment. | 0 |
[0001] This application is a divisional of application Ser. No. 10/444,225, filed May 23, 2003, U.S. Pat. No. 7,353,571, issued Apr. 8, 2008, and this application incorporates by reference herein the entirety thereof.
FIELD OF THE INVENTION
[0002] The invention relates generally to attachment devices having a fluid-containing cavity.
BACKGROUND OF THE INVENTION
[0003] Attachment devices such as snap hooks and carabiners have long been in use for providing a means for attaching articles to each other. Such devices have numerous applications, such as for example enabling multiple articles to be secured to a backpack, purse, handbag, key chain or the like. As such, these devices are fairly ubiquitous. An example of an attachment device is a carabiner such as is disclosed in U.S. Pat. No. 5,005,266.
[0004] Fluid-filled ornamental articles are known in the art. For example, U.S. Pat. No. 4,148,199 relates to a pierced earring with liquid visible therein. U.S. Pat. No. 4,093,973 relates to a liquid filled ornamental article of jewelry containing an illumination source. U.S. Pat. No. 5,006,375 relates to an ornamental article having a transparent housing shaped into a decorative configuration having a liquid therein and a subatmospheric pressure area between the liquid and housing. However, none of the prior art liquid filled ornamental articles have the utility of providing a means for attaching articles to each other and providing an indicia bearing means on a ubiquitous useful article.
SUMMARY OF THE INVENTION
[0005] The invention provides an attachment device comprising at least one fluid filled cavity formed therein. The attachment device is preferably in the form of a carabiner in which at least a portion of the carabiner body is formed of a transparent material such that the fluid filled cavity is visible. In a preferred embodiment an indicia bearing means is visibly disposed within said cavity.
OBJECTS OF THE INVENTION
[0006] It is an object of the present invention to provide a fluid filled attachment device that is aesthetically pleasing.
[0007] It is a further object of the present invention to provide a novel attachment device that provides an interior fluid filled cavity capable of containing an indicia-bearing medium.
[0008] It is still a further object of the present invention to provide in a novel attachment device a free-floating indicia-bearing medium in said fluid filled cavity.
[0009] It is yet a further object of the present invention to provide in a novel attachment device a fixed indicia-bearing medium in said fluid filled cavity.
[0010] It is still a further object of the present invention to provide a novel attachment device in the form of a carabiner that provides an interior fluid filled cavity capable of containing an indicia-bearing medium.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a front view of a preferred embodiment of the present invention;
[0012] FIG. 2 is a perspective view of a preferred embodiment of the invention of FIG. 1 ;
[0013] FIG. 3A is a cross sectional view of the invention of FIG. 2 taken along the line A-A′;
[0014] FIG. 3B is a cross sectional view of another embodiment of the invention of FIG. 2 taken along the line A-A′;
[0015] FIG. 4 is a perspective view of a further preferred embodiment of the present invention;
[0016] FIG. 5 is a cross sectional view of the invention of FIG. 4 taken along the line B-B′; and
[0017] FIG. 6 is a perspective view of a further preferred embodiment of the present invention.
[0018] FIG. 7 is a perspective view of a further preferred embodiment of the present invention.
[0019] FIG. 8 is a front perspective view of a further preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0020] Now referring to FIGS. 1-3 , a preferred embodiment of the device 2 comprises essentially a body member 10 , at least one openable gate member 20 , at least one cavity 30 formed in the device 2 and a fluid 35 contained in said cavity 30 . Device 2 optionally further includes an indicia-bearing device 40 contained in said cavity 30 .
[0021] Body member 10 comprises an elongated member comprising a first end and a second end and is fabricated of any material suitable for attachment devices such as but not limited to bare or coated metal, wood, rubber or plastic or combinations thereof. Gate member 20 comprises an elongated member pivotally attached at one end to one end of said body member 10 . The other end of gate member 20 contacts the other end of said body member 10 when said gate 20 is in a closed position. Now referring to FIG. 2 , in a preferred embodiment gate member 20 is inwardly openable. Gate member 20 is fabricated of any suitable material as recited above for body member 10 . In a preferred embodiment body 10 is curvilinear. In a most preferred embodiment body member 10 is formed in the shape of a carabiner.
[0022] Cavity 30 is formed in either or both of body member 10 and gate member 20 . Cavity 30 may be formed of a depression or hollow in the material of body member 10 or gate member 20 , for example where the material is formed of a nontransparent material such as metal, wood, rubber or opaque plastic and sealed with a transparent material such as but not limited to readily available plastics or acrylics, polycarbonates, polyimides, methacrylates, polystyrenes or the like such that the interior of the cavity 30 is visible. Now referring to FIGS. 2 and 3 , alternatively, where the material of the portion of the device 2 wherein the cavity 30 is formed is a transparent material the cavity 30 can be a chamber formed therein by thermoforming, blow molding, boring or the like. Now referring to FIGS. 4 and 5 , in yet another embodiment cavity 30 is formed between a portion of body member 10 and a transparent shell member 12 .
[0023] Fluid 35 is any suitable substance that is nonreactive when employed in conjunction with the material of cavity 30 . Suitable fluids 35 include colored or uncolored liquids such as but not limited to water, oil or gel or mixtures thereof, or, as seen in FIG. 2 , small particulate matter 37 such as but not limited to colored or uncolored powders, grains or the like or mixtures thereof, and/or as also seen in FIG. 2 at 35 and 37 mixtures of liquids and solid particles. In a preferred embodiment fluid 35 is transparent. As is also seen in FIG. 2 , those skilled in the art will recognize materials such as reflective or refractive material including but not limited to glitter and/or other insoluble material 37 may be included in fluid 35 for aesthetic purposes. It will also be recognized fluid 35 may contain a colorant. It is to be understood herein that each and every other of the embodiments of the other figures herein may also have the above particulate matter, glitter, etc. 37 within fluid 35 .
[0024] Indicia bearing device 40 is contained in cavity 30 and may be fixedly anchored within said cavity 30 (as seen in FIG. 3B ) or may be unanchored so as to be free-floating or free-moving within said cavity 30 (as seen in FIG. 3A ). Accordingly indicia bearing device 40 may be fabricated of any suitable material that is nonreactive with fluid 35 . Suitable materials are any materials capable of receiving indicia such as ink, engraving, paint, or the like and include but are not limited to metal, wood, laminate, plastic, cork, rubber and the like. Indicia bearing device 40 may have any configuration as long as such configuration can be received and contained in said cavity 30 . Now referring to FIGS. 2 and 3 in a preferred embodiment indicia bearing device 40 is elongated and has a three dimensional cross section, providing more than one indicia bearing surface 42 . As seen in FIG. 3 , in one embodiment indicia bearing device 40 comprises three indicia bearing surfaces 42 and each surface 42 may for example bear different indicia.
[0025] In a preferred embodiment device 2 comprises a curvilinear body 10 , body 10 comprises metal having at least one cavity 30 formed therein, said cavity 30 sealed by a transparent plastic material, said cavity 30 containing a fluid 35 comprising water and further containing indicia bearing device 40 , wherein said indicia bearing device 40 is elongated and is free floating in fluid 35 .
[0026] Now referring to FIG. 6 in a most preferred embodiment device 2 comprises a cavity 30 formed in gate 20 and body 10 is in the shape of a carabiner.
[0027] Now referring to FIG. 7 , in an alternate preferred embodiment body 10 is in the form of a circle.
[0028] Now referring to FIG. 8 , in a further preferred embodiment of the present invention, cavity 30 comprises a significant portion of the device 2 .
[0029] As illustrated in FIGS. 7 and 8 , device 2 is not limited to the form of a carabiner but may take any suitable shape or form.
[0030] While the preferred embodiments have been described and illustrated it will be understood that changes in details and obvious undisclosed variations might be made without departing from the spirit and principle of the invention and therefore the scope of the invention is not to be construed as limited to the preferred embodiment. | An attachment device is provided comprising at least one fluid filled cavity formed therein. The attachment device is preferably in the form of a carabiner in which at least a portion of the carabiner body is formed of a transparent material such that the fluid filled cavity is visible. In a preferred embodiment an indicia bearing means is visibly disposed within said cavity. | 5 |
FIELD OF THE INVENTION
[0001] The invention relates to ink jet printers and to improved methods for making printheads for ink jet printers.
BACKGROUND
[0002] Ink jet printers continue to evolve to provide print engines having increased resolution at higher page throughput. However, higher throughput often means the printheads must operate with higher ejection frequencies which often increase the printhead temperature. Higher printhead operating temperatures and more chemically aggressive inks require more robust construction or modification in fabrication techniques to enhance the ability of the components of the printhead to withstand more extreme operating conditions and inks. For example, increased operating temperatures may cause failure of adhesives used to attached printhead components to one another. Failure of adhesion between protective layers attached to the semiconductor surface may invite corrosion from ink contact with unprotected surfaces including the electrical devices on the semiconductor surface.
[0003] What is needed therefore is an improved method for fabricating ink jet printheads to reduce the potential for corrosion from ink over the life of the printhead.
SUMMARY OF THE INVENTION
[0004] With regard to improving manufacturing techniques so as to provide printheads having increase reliability over the life thereof, a method for improving adhesion between a polymeric planarizing film and a semiconductor chip surface is provided. The method includes depositing resistive, conductive and/or insulative materials to a silicon wafer surface to provide semiconductor chips for ink jet printers. The wafer surface is treated with a dry etch process under an oxygen atmosphere for a period of time and under conditions sufficient to activate the surface of the wafer. A polymeric planarizing film is applied to the activated surface of the wafer. As a result of the dry etch process, adhesion between the planarizing film and the wafer surface is increased over adhesion between a planarizing film and a wafer surface in the absence of the dry etch treatment of the wafer surface.
[0005] In another aspect, the invention provides a semiconductor chip for an ink jet printhead. The chip includes silicon having a device surface and one or more metal or metal oxide layers providing active devices on the device surface. The device surface is activated for bonding a planarizing film thereto. A planarizing film is attached to and covers at least a portion of the activated surface of the semiconductor chip. The surface is activated by treating the surface with a dry etch process under oxygen atmosphere to provide increased adhesion between the planarizing film and the device surface.
[0006] An important advantage of the invention is that the printhead exhibits improved life even when operating at higher temperatures and when using more chemically aggressive inks. A factor in the improved life of the printhead is the decreased tendency for the planarizing film to delaminate from the device surface of the chip when a printhead is made by the process of the invention. Because the planarizing film of the invention is more prone to remain completely attached to the device surface, corrosion of the device surface by ink contact therewith is significantly reduced. In comparison, printheads made by planarizing unactivated device surfaces are more prone to delamination between the planarizing film and chip surface than printheads made according to the invention. Delamination of the planarizing film provides an avenue for ink corrosion of the device surface of the chip.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Further advantages of the invention will become apparent by reference to the detailed description when considered in conjunction with the figures, which are not to scale, wherein like reference numbers indicate like elements through the several views, and wherein:
[0008] [0008]FIG. 1 is a cross-sectional view, not to scale, of a portion of semiconductor chip containing a planarizing surface applied to the chip according to the invention;
[0009] [0009]FIG. 2 is a cross-sectional view, not to scale, of a portion of a printhead made according to the invention; and
[0010] FIGS. 3 - 7 are cross-sectional views, not to scale, of a portion of a semiconductor chip during the manufacturing processes therefor.
DETAILED DESCRIPTION OF THE INVENTION
[0011] With reference to FIG. 1, a semiconductor chip 10 for an ink jet printhead is shown. The chip 10 includes a silicon substrate 12 containing a plurality of layers including insulating, conductive, resistive and passivating layers which together provide a device layer 14 on the silicon substrate 12 . The chip 10 is made from a silicon wafer having a thickness ranging from about 200 to about 800 microns and the device layer 14 preferably has an overall thickness ranging from about 1 micron to about 5 microns, most preferably from about 2 to about 3 microns. A planarizing layer 16 is deposited over the device layer 14 to provide a substantially planar surface 18 for attaching a nozzle plate 20 (FIG. 2) thereto.
[0012] With regard to providing device layer 14 , reference is made to FIGS. 3 - 7 . The first layer applied to the silicon substrate 12 is an insulating layer 22 (FIG. 3) which is preferably a metal oxide layer, most preferably silicon dioxide having a thickness ranging from about 1.0 to about 2.0 microns. However, other passivating or insulating layers may be used for layer 22 .
[0013] The next layer is a phosphorous silicon glass (PSG) layer 24 (FIG. 4) having a thickness ranging from about 1000 to about 1200 Ångstroms which is deposited over the insulating layer 22 . Other materials which may be used for layer 24 include boron phosphorous silicon glass (BPSG) or other dielectric materials known to those skilled in the art. The PSG layer 24 is preferably deposited over the entire insulating layer 22 surface.
[0014] A resistive layer 26 of tantalum/aluminum, or alpha phase tantalum is next deposited on at least a portion of the PSG layer 24 (FIG. 5). The resistive layer 26 provides heater resistors 28 which are disposed adjacent an ink chamber 30 and ink ejection nozzle hole 32 (FIG. 2) provided in the nozzle plate 20 attached to the chip 10 . Upon activation of the heater resistors 28 , ink in the ink chamber 30 is heated and a portion of the heated ink vaporizes causing a gas bubble which urges ink from the ink chamber 30 through the nozzle hole 32 . The resistive layer 26 preferably has a thickness ranging from about 900 to about 1100 Ångstroms.
[0015] Conductive layers 34 a and 34 b (FIG. 5) made of an aluminum/copper alloy, gold, beta phase tantalum, aluminum and the like are deposited on one or more portions of the resistive layer 26 . The conductive layers 34 a and 34 b provide electrical connection between the resistors 28 and the printer controller. Conductive layers 34 a and 34 b each preferably have a thickness ranging from about 5000 to about 6000 Ångstroms.
[0016] In order to protect the conductive and resistive layers from ink corrosion, passivation layers 36 and 38 (FIGS. 5 and 6) are preferably deposited over the resistive layer 26 and conductive layers 34 a and 34 b. The passivation layers 36 and 38 may be a composite layer of silicon nitride and silicon carbide, or may be individual layers 36 and 38 of silicon nitride and silicon carbide, respectively. The passivation layers 36 and 38 are preferably deposited directly on the conductive layers 34 a and 34 b and the resistive layer 26 . It is preferred that the silicon carbide layer 38 have a thickness ranging from about 2000 to about 3000 Ångstroms, most preferably about 2600 Ångstroms. The silicon nitride layer 36 preferably has a thickness ranging from about 4000 to about 5000 Ångstroms, most preferably about 4400 Ångstroms.
[0017] A cavitation or additional passivation layer 40 (FIG. 6) of tantalum or diamond like carbon (DLC) is preferably deposited over at least a portion of the passivation layers 36 and 38 , most preferably adjacent the heater resistor 28 adjacent the ink chamber 30 . The cavitation layer 40 provides protection to the heater resistor 28 during ink ejection operations which could cause mechanical damage to the heater resistor 28 in the absence of the cavitation layer 40 . The cavitation layer 40 is believed to absorb energy from a collapsing ink bubble after ejection of ink from the nozzle hole 32 . Cavitation layer thickness may range from about 2500 to about 7000 Ångstroms or more.
[0018] As seen in cross-sectional view in FIG. 6, the insulative, conductive, resistive and passivative layers providing device layer 14 deposited on the silicon 12 result in a non-planar chip surface 42 . Each of these layers may be deposited and patterned as by conventional thin film integrated circuit processing techniques including chemical vapor deposition, photoresist deposition, masking, developing, etching and the like.
[0019] In order to adhesively attach the nozzle plate 20 to the chip surface 42 , the planarizing layer 16 (FIG. 7) is preferably spun or coated onto the chip surface 42 as an intermediate layer to provide a planarized surface 18 . The planarizing layer 16 is preferably a radiation and/or heat curable polymeric film layer preferably containing a difunctional epoxy material, a polyfunctional epoxy material and suitable cure initiators and catalyst. A suitable material for planarizing layer 16 is described in U.S. Pat. No. 5,907,333 to Patil et al., the disclosure of which is incorporated herein by reference as if fully set forth.
[0020] The planarizing layer 16 is relatively thick compared to the insulative, conductive, resistive and passivating layers described above and may have a thickness ranging from about 1 micron to about 20 microns, preferably about 2 to about 3 microns and most preferably about 2.5 microns. It is preferred to deposit the planarizing layer 16 over the entire chip surface 42 and then selective remove the layer in selected areas, i.e., “pattern” the layer, to provide the ink chamber 30 and electrical connections to conductive layers 34 a and 34 b on the chip 10 . Patterning the planarizing layer 16 may be conducted by conventional photolithographic techniques.
[0021] Once the surface 42 of the chip 10 is substantially planarized with planarizing layer 16 , the nozzle plate 20 may be attached to the planarizing layer 16 using adhesive 44 (FIG. 2). The nozzle plate 20 may be made of metals or plastics and is preferably made of a polyimide polymer which is laser ablated to provide the ink chamber 30 , nozzle hole 32 and an ink supply channel 46 therein. The adhesive layer 44 is preferably any B-stageable material, including some thermoplastics. Examples of B-stageable thermal cure resins include phenolic resins, resorcinol resins, urea resins, epoxy resins, ethylene-urea resins, furane resins, polyurethanes, and silicon resins. Suitable thermoplastic, or hot melt, materials include ethylene-vinyl acetate, ethylene ethylacrylate, polypropylene, polystyrene, polyamides, polyesters and polyurethanes. The adhesive layer 44 is about 1 to about 25 microns in thickness. In the most preferred embodiment, the adhesive layer 44 is a phenolic butyral adhesive such as that used in RFLEX R1100 or RFLEX R1000 films, commercially available from Rogers of Chandler, Ariz.
[0022] A flexible circuit or tape automated bonding (TAB) circuit is attached to the nozzle plate/chip assembly 20/10 to provide a printhead structure. The printhead structure is preferably adhesively attached to a printhead body portion to provide a printhead for an ink jet printer.
[0023] As set forth above, the invention significantly improves adhesion between the planarizing layer 16 and the chip surface 42 . While not desiring to be bound by theory, it is believed that dry etching the chip surface 42 in an oxygen atmosphere prior to attaching the planarizing layer 16 to the surface 42 may sufficiently oxygenate and/or clean the surface 42 and provide adhesion improvement between the planarizing layer 16 and the surface 42 . It is believed that reactive ion etching (RIE) deep reactive ion etching (DRIE) or inductively coupled plasma (ICP) etching generates gaseous oxygen ions which impact the chip surface 42 substantially perpendicular to the chip surface 42 . The directionality of the gaseous ions in the etching chamber distinguishes such processes from a non-directional movement of ions in conventional plasma processes.
[0024] Operating parameters for the etching process are also important to achieving the desired adhesion improvement. The same adhesion enhancing effect is not evident with all operating parameters. For example, the preferred RF power for RIE ranges from about 200 to about 400 watts with about 300 watts being particularly preferred. The reaction chamber pressure is also important to achieving suitable results. The pressure preferably ranges from about 200 to about 650 milliTorr, most preferably from about 450 to about 600 milliTorr. The gas used to generate plasma in the reaction chamber is particularly important to effective enhancement of adhesion. Accordingly, it is preferred to use a plasma gas consisting essentially of oxygen. Oxygen is delivered to the reaction chamber at a flow rate ranging from about 100 to about 300 standard cubic centimeters per minute (sccm), most preferably from about 200 to about 250 sccm. RIE treating time should be sufficiently long to effect oxygenation and/or cleaning of the chip surface but not so long that significant reduction in the surface layers is effected. A preferred RIE treating time ranges from about 30 to about 120 seconds, most preferably about 60 seconds. For example, RIE at 100 watts power, 100 millitorr and pure oxygen for 1 to 10 minutes was not found to increase adhesion between the surface 42 of a semiconductor chip and a planarizing layer 16 applied to the surface 42 .
[0025] While the foregoing invention has been described with reference to a thermal ink jet printer, the invention is adaptable to use in fabricating a piezoelectric ink jet printer. In this case, the chip surface to which the planarizing layer 16 is applied is on a side of the silicon 12 opposite the surface to which the nozzle plate 20 is attached. However, since the chip 10 containing the piezoelectric devices is adhesively attached to a printhead body, it is desirable to include planarizing layer 16 to provide a planar surface for such adhesive attachment. Activation of the device surface of a piezoelectric type chip to improve adhesion between the planarizing layer 16 and the device surface provides similar advantages for the construction of piezoelectric printheads.
[0026] Having described various aspects and embodiments of the invention and several advantages thereof, it will be recognized by those of ordinary skills that the invention is susceptible to various modifications, substitutions and revisions within the spirit and scope of the appended claims. | The invention provides a method for improving adhesion between a polymeric planarizing film and a semiconductor chip surface. The method includes deposition resistive, conductive and/or insulative materials to a seimconductor chip surface to provide a semiconductor chip for an ink jet printer. The chip surface is treated with a dry etch process under an oxygen atmosphere for a period of time and under conditions sufficient to activate the surface of the chip. A polymeric planarizing film is applied to the activated surface of the semiconductor chip. As a result of the dry etch process, adhesion of the planarizing film is increased over adhesion between the planarizing film and a semiconductor surface in the absence of the dry etch treatment of the chip surface. | 1 |
BACKGROUND
[0001] This invention relates to the processing of metal powders, for example, by a combination of thermally based (e.g. laser, or electron beam) Additive Layer Manufacturing (ALM) and subsequent heat treatments that then form a superalloy and in particular gamma prime phase containing superalloys.
[0002] Superalloys are alloys strengthened not only by the nature of their matrix and chemistry but also by the presence of special strengthening phases, usually precipitates. For a fuller description of superalloys see “Superalloys: A Technical Guide” ASM International ISBN 0-87170-749-7 and “The Superalloys: Fundamentals and Applications” Cambridge University Press ISBN-10 0-521-85904-2. These are alloys that have been developed recently for use in rocket and jet engines.
[0003] A superalloy is generally defined as an alloy with excellent mechanical strength and creep resistance at high temperatures, good surface stability, and corrosion and oxidation resistance. Some of the most useful form secondary phase precipitates such as gamma prime and these gamma prime precipitates frequently include titanium and aluminium. These superalloys present numerous processing challenges are frequently represented on a diagram as shown at FIG. 1 . The inventor has broadly observed that those superalloys to the left of the ‘weldability’ line e.g. Inconel 718 can be ALM processed without bulk heating to a high temperature, whereas the superalloys to the right of the ‘weldability’ line cannot.
[0004] It is well known that functional metal parts can be manufactured from a variety of pure metals and alloys using ALM. Historically a so-called “Liquid Phase Sintering” process was used to form mechanically hard parts such as moulds from proprietary multicomponent metal powder e.g. DirectMetal 20 and DirectSteel—products of EOS GmbH. Liquid Phase Sintering describes a process where one lower melting point component of the powder is melted by the laser, but the other higher melting point components remain solid. DirectMetal is described as “bronze-based matrix containing nickel” by its manufacturers with a remaining porosity of 8% and no heat treatment required or described. DirectSteel H20 is described as a “steel based multi-component metal powder” which when laser sintered formed a steel alloy of greater than 99.5% density which has 5-10% improved tensile strength and 10˜15% improved yield strength after a heat treatment.
[0005] More recently with better suited lasers a full melt of many homogeneous metal powders has become commonplace. The powder feedstock for such parts is chemically homogeneous to the resultant alloy and made by the melting of a chemically homogeneous bar stock or elements and is of the composition required for the finished part.
[0006] In the best prior art ALM process the powder is fully melted where desired by the selective application of an energy source (typically a laser or electron beam) and then solidifies in order to produce, layer by layer, a fully dense metal part corresponding to a sliced design file. As the powder is fully melted and many metals and alloys have a high coefficient of thermal expansion the as-built part typically has considerable internal stresses and to retain dimensional accuracy the part is restrained by a build plate or jigs and fixturings during the build and throughout a subsequent heat treatment to substantially remove these stresses prior to removal from the base plate, jigs or fixtures. Additionally many metals go through a phase change as they cool from liquid adding further stresses.
[0007] In some alloys however—particularly nickel-based superalloys—the internal stress is sufficient to cause cracking of the part either during the ALM process or during the subsequent stress relief heat treatment. For example, an important subset of nickel superalloys with gamma prime alloying elements show this behaviour and are known to be difficult to work by conventional processes and are frequently classified as ‘unweldable’. These alloys are also of significant commercial interest as they are widely used for very high temperature applications—such as in combustion components in engines and frequently can only be cast and are difficult or impossible to repair.
[0008] The prior art solution is to add heat to the area of the melting metal to minimise thermal mismatching of the solid metal already formed and solidifying. In the case of lower melt temperature metals e.g. titanium, this may be a practical pragmatic solution, however for the superalloys particularly nickel based superalloys of interest it is either practically or commercially disadvantageous to heat the part because of the high temperatures necessary but also the time for which that temperature needs to be applied and the controlled cooling to achieve a sufficient stress reduction and no cracking.
[0009] Bourell U.S. Pat. No. 5,296,062 discloses the use of “powder comprising particles of a first material coated with a second material, said second material having a lower softening temperature than said first material”.
[0010] Bampton in U.S. Pat. No. 5,745,834 describes various methods for “selective laser binding and transient liquid sintering of blended powders”. These include a method where 3% Boron (a known melt point depressant) is added to a top layer of Haynes 230 superalloy powder representing 15% of the total layer thickness and a pre-heat applied to a temperature just below the melt point of the layer with Boron added. A laser is then applied to selectively melt the layer with the melt temperature depressant Boron. This liquid metal wicks into the 85% layer thickness beneath it and the Boron diffuses out of the liquid phase into the solid powder to produce “a nearly fully dense segment of the component.” Bampton points out that it is difficult to process at such a high (pre-heat) temperature on conventional equipment and that there is a significant temperature gradient from the laser melted spot of typically in excess of 100 deg C. and the bulk thereby creating residual stresses.
[0011] Bampton also describes a process where polymer powders are blended with the metal and a laser layer process carried out. The binder is burnt out leaving a porous metal powder solid state sintered together. This porous sintered part is then densified by either encapsulation and then Hot Isostatic Pressing or a lower melting point liquid metal infiltration. Both processes have significant disadvantages. The HIP'ed object will have substantially shrunk—and this process is laborious. In the case of the liquid metal infusion, the solid part is not 100% of the desired alloy and therefore does not have the desired mechanical properties.
[0012] Bampton then describes a mix of three powder components including the desired parent metal, the same base metal with melt point depressant and a polymer binder where the layers are built “by localized laser melting of the polymer constituent of the powder which rapidly resolidifies to bind the metal particles of the powder with connecting necks or bridges.” The binder is then eliminated in a furnace creating a low strength part (generally) requiring temporary support from e.g. ceramic powder during a transient liquid sintering process.
[0013] Also known (WO/0211928) are all metal powders (no polymer) with melt temperature depressant additives e.g. Boron or Carbon included. And the additions may be at a small percentage of total powder but when used as a discrete powder it may local present at far higher percentages thereby initiating melting, wetting and bonding of the powder to form an object that is substantially fully dense.
[0014] Similarly US2004/0182201 describes a process where “graphite is also used in sintering iron based powder for the purpose of lowering the melting point of the composition to be sintered . . . ” “graphite powder is considerably effective to improve the wettability during melting or to reduce microcracks during solidification of high-density portions”.
[0015] In Hede, WO 02/092264 the then current (November 2002) method and powders for Selective Laser Sintering with metal powders and laser (and all known free form methods) is described as not capable of producing a fully dense material-5-30% porosity remaining; Infiltration with a low melting point material being required.
[0016] Hede describes trials with tools steels leading to “a martensitic layer of high hardness and internal stresses making it difficult (impossible) to smooth the layer deposited with a scraper before applying the next layer” and with “a major risk of fissuring”.
[0017] Hede then describes the use of iron and copper based precipitation hardening alloys that would “give a soft material directly after laser sintering . . . the desired hardness could then instead by achieved by precipitation hardening . . . after laser sintering.” Iron alloys and in particular a maraging steel and 17-4PH stainless steel is described. Whilst the maraging steel 18NiMAR250 was tested Hede then goes on to speculate more broadly including 17-4PH as an example material that will precipitate harden.
[0018] At this time (2011) 17-4PH stainless steel alloy is one of the most widely used metal powders in laser Selective Laser Sintering equipment and has been so for many years. The applicants use it in their business on a daily basis. As recently as 2006 it was widely described (e.g. by EOS GmbH) as ‘precipitation hardening’ but in fact it has been found by the applicants that 17-4PH alloy powder does not precipitate harden after processing in the commercially available EOS M270 machine and 17-4 powder is no longer marketed as a precipitation hardening powder material. Clearly we are in a new area where broad speculation cannot be relied upon as a good guide to materials performance in selective laser processing plus post-build heat treatments.
[0019] Tegal DE 10039143 at [003] describes the problem to solve as being high levels of porosity when metallic components are produced from conventional powder mixtures. He describes a density of approximately 90% of the theoretical density with a steel powder and in laser-sintered parts of bronze, a residual porosity of about 30% remains.
[0020] The disclosure describes laser sintering a powder material comprising a mixture of at least two powder elements and is characterized in that the powder mixture is formed by iron powder as the main component and by further powder alloying elements, which are present in an elementary, pre-alloyed or partly alloyed form and that a powder alloy results from these powder elements in the course of the laser sintering process.
[0021] Tegal further amplified this by saying the powder alloying components are converted during the laser sintering process within milliseconds into a powder alloy, of which the component consists. Any subsequent treatments are described as for homogenization, stress relief annealing, heat treatment, reduction in internal defects and improvement in the surface quality.
[0022] It should be noted that the state of the art has advanced considerably since this disclosure was filed in the year 2000 and with current generation equipment (that fully melts rather than sintering the metal powder) porosity on the scale described by Tegal is no longer a problem.
SUMMARY
[0023] By contrast the processes and materials we describe here do not need to contain coated powder, polymers or require the formation of a porous or ‘green’ state prior to subsequent heat treatments. We are not trying to solve a porosity problem resulting from sintering (not melting) the metal powder. We are creating a superalloy, not creating a ‘soft’ material or a precipitation hardening iron or copper based alloy that is subsequently precipitate hardened. We are not adding or using a melt point depressant such as boron or graphite (carbon) to achieve the process of the invention. We are also not forming the alloy during the laser ‘sintering’ process—we are explicitly not forming the alloy then, because this would result in failure as the alloy we wish to form will crack in the laser process. We are forming the alloy during a subsequent heat treatment cycle.
[0024] From one aspect the invention consists in a method of forming an article including:
[0025] (i) forming a layer of a mixture of at least two distinct metal powders selected such that when combined they are chemically in the proportions of a superalloy containing a gamma prime phase
[0026] (ii) fusing the powders locally without diffusion to define the shape of a part of the article such that the materials of the distinct metal powders remain substantially chemically segregated forming regions of different chemical composition
[0027] (iii) repeating steps (i) and (ii) until the derived article is formed; and
[0028] (iv) heat treating the finished article such that at least one of the distinct separate materials diffuses to form a gamma prime phase containing superalloy with the other.
[0029] The invention also consists of a metal powder for layer processing, chemically comprising the elements of a gamma prime forming superalloy less a substantial portion of one of its gamma prime forming alloying elements. The alloy may generally be nickel based and the gamma prime forming element mayl generally be aluminium. Well known gamma prime hardened superalloys include: Inconel 713C, Inconel 100, MAR M247, MAR M200, Inconel 738, RR1000, UDIMET 500, Inconel 939, Unimet 720, MAR M002, CMSX-4, Haynes 282, Rene 41,
[0030] This metal powder can be present alone or as a mix comprising this metal powder mixed with a second powder chemically comprising its gamma prime forming elements such that together they form a non-homogenous physical mix of powders. This mix of powders chemically can then equate to a recognised nickel superalloy. The second powder can contain aluminium and also titanium and could conveniently be titanium aluminide (TiAl, TiA13, Ti3Al).
[0031] What the Applicants have appreciated is that using, for example, a locally acting laser to fuse the desired parts of the material together to form the shape of a layer of the article, they can build up an effective matrix, in the shape of the intended article, from one powder of the component of the mixture and hold the other powder constituent in a substantially chemically segregated manner. Thus by selecting the powder which forms the matrix, i.e. the bulk powder, to be one which does not have high internal stresses that induce cracking, they can form an article that does not readily crack either during ALM building on removal from the base plate and/or under a first heat treatment to stress relieve the article.
[0032] Thus in a preferred embodiment the mixture of powders includes one powder component which constitutes over 50% of the mixture and thus forms the matrix bulk of the article. Preferably the component forms over 60% by weight of the mixture. In some embodiments the component can be nickel or in other embodiments the bulk component can be nickel and chromium. In still further embodiments the bulk component may include or consist of iron.
[0033] In a preferred embodiment the diffusion in step (iv) takes place by solid state diffusion.
[0034] As mentioned above the method may also include stress relieving the article by heat treatment prior to step (iv).
[0035] In a particularly preferred embodiment wherein it is intended to form a superalloy containing an additive x at a concentration C. The method may include blending two powders A and B wherein A is the intended bulk constituent of the superalloy having a concentration of an additive x where x=(C x ) A selected to allow processing without cracking and wherein powder B is a minor constituent of the intended alloy with a concentration of x=(C x ) B ; blending the powders A and B together so that B is a fraction of f of the whole such that C x =f(C x ) B +(1−f)·(C x ) A and wherein (C x ) B >(C x ) A .
[0036] Each of the powders may be melted locally during step (ii). The powders may be selected out of materials less susceptible to stress cracking than the intended alloy. The intended alloy may be a nickel based superalloy. The alloy may include an additive x which may be aluminium or titanium or both. X may form more than 4% by weight of the powder.
[0037] From another aspect the invention consists in selecting and mixing two or more powder compositions that chemically add to the proportions of a desired superalloy and performing an additive layer process on this mixture such that they fully melt to form a substantially dense metal mix that is not the desired superalloy and which is characterised as having a sufficiently low stress so as not to crack during building or subsequent heat treatments and heat treating the metal mix to form the desired superalloy without cracking.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] Although the invention has been defined above it is to be understood it includes any inventive combination of the features set out above or in the following description. The invention will now be defined, by way of example, with reference to the accompanying drawings in which:
[0039] FIG. 1 is a known chart indicating the world ability of nickel alloys with aluminium and/or titanium additives;
[0040] FIG. 2 is a flow diagram of an embodiment of the invention;
[0041] FIG. 3 is a micrograph of a sample after ALM; and
[0042] FIG. 4 is a micrograph of a sample after ALM and subsequent heat treatment.
DETAILED DESCRIPTION
[0043] FIG. 1 is a diagram taken from Nickel Based Superalloy Welding Practices for Industrial Gas Turbine Applications by MB Henderson and others and is after a diagram found in G. Cam and M Kocak, ‘progress in joining advanced materials’ International Materials reviews, 43, no 1 (1988). Similar diagrams are widely found in the literature concerning welding and strain age cracking of alloys containing gamma prime precipitates.
[0044] At this time this diagram (and inferences drawn from it) is believed by the inventor to give a good guide as to which superalloys are thermal ALM processable ‘crack free’ by the prior art. For the purposes of this analysis thermally based ALM may be considered as a type of welding. It is said that when the total aluminium and titanium level of a particular alloy exceeds a threshold value often taken as 4 wt % then it is deemed ‘difficult’ to weld, becoming increasingly more difficult as the percentage increases.
[0045] FIG. 2 is the process flow of the embodiment invention. Note that alloy A and Alloy B need not be recognised alloys because the metal powder feedstock for the ALM process may be made to order from elemental materials and any composition may therefore be ordered at no additional cost or delay.
[0046] FIGS. 3 and 4 are respectively micrographs of a sample of an embodiment of the invention immediately after ALM and a sample after ALM and subsequent heat treatment.
[0047] Thus the inventor has recognised the following new possibilities:
[0048] 1] The selection and mixing of two or more powder compositions that chemically add to the proportions of the desired superalloy,
[0049] 2] Additive layer processing this mix of powders where they fully melt to form a substantially fully dense metal ‘mix’ that is not the desired superalloy and is characterised as having a sufficiently low stress as to not crack during building or subsequent heat treatments,
[0050] 3] Heat treatments of the metal mix to form the desired superalloy without cracking.
[0051] It should be noted that the stresses generated by a near ambient temperature thermal ALM powder bed process are such that a substantial base plate typically weighing 20 KG is required to resist mechanical relaxation caused by the as-built stress. This significantly complicates further thermal processing as it adds significantly to the thermal mass. A method that allows the part to be removed from a base plate or jigs and fixturing crack free prior to high temperature and sophisticated heat treatments is therefore desirable.
[0052] In a particular embodiment powder A has an elemental chemical composition approximating an “easy to process” alloy and would generally be the major constituent of the powder mixture. Powder B on the other hand has a chemical composition of elements such that when blended with Powder A in the correct ratio, will result in an overall chemical composition of its elements corresponding to that of the desired final superalloy. Thus if we wish to manufacture parts from a superalloy containing an additive element x at concentration C x we would blend two powders, A and B. Powder A being the bulk constituent would have a lower concentration of element x, (C x ) A , such that it could be processed without cracking. This is referred to below as the “bulk powder”. Powder B being the minor constituent would have a higher concentration of element x, (C x ) B and would be blended with powder A to make up a fraction f of the whole, such that:
[0000] C x =f ·( C x ) B +(1 −f )·( C x ) A Equation 1
[0000] Powder B is referred to below as the “dopant powder”.
[0053] During ALM processing, both Powder A and Powder B will be fully melted but, due to the short time spent in the liquid phase, would remain as substantially segregated regions with differing chemical compositions.
[0054] If several additive elements are employed in an alloy, then the dopant powder can have the appropriate concentrations of each of them. Alternatively, further dopant powders can be blended, each introducing a different element. Clearly it might sometimes be beneficial to introduce all of a particular additive element within a dopant powder. Furthermore, in the limit, a dopant powder could be pure additive element.
[0055] The resulting structure in the ALM formed part will be that of isolated islands of material having the approximate composition of the dopant powder, surrounded by a matrix of material having the approximate composition of bulk powder. Because the mechanical properties and internal stresses are dominated by the bulk powder, the resulting material may be ALM built and heat treated without cracking. It should be noted that the as-built part is fully melted, essentially dense and chemically equal to the desired superalloy, but is not in the microstructure of the desired superalloy. The microstructure is generated as a discrete second stage process by heat treatment.
[0056] It is known that powder blends are sometimes used in ALM to e.g. manufacture mould tools by laser sintering—one such process is Direct Metal Laser Sintering. It should be noted that such sintering processes do not fully melt the material, the material is not fully dense and heat treatments are not employed to form a high performance superalloy—the use of the term ‘direct’ indicates that further heat treatments are not necessary to form the desired material.
[0057] In the invention a subsequent heat treatment (single step or multistep) is then employed to cause additive x to diffuse out of the high concentration dopant islands into the low concentration bulk, resulting in a superalloy of the required microstructure with e.g. the characteristic precipitation of the final alloy and in particular the gamma prime precipitates.
[0058] A suitable heat treatment may include solution and aging steps. Firstly dissolving the gamma prime precipitates, topologically closed packed phases and carbides into the gamma matrix and then aging to form the precipitates and carbides into the desired shapes and configurations. In this manner a part in the high performance superalloy is achieved without cracking.
[0059] In a preferred embodiment for the addition of both aluminium and titanium, it is convenient to add an appropriate quantity of one of the titanium aluminide inter-metallics. A proof of principle experiment has been performed using a bulk powder made from the nickel superalloy C263. To this was added 4 weight. % of TiAl 3 powder. C263 is a gamma prime containing alloy having moderate concentrations of aluminium and titanium. It is generally regarded as a weldable alloy and can be ALM processed without cracking. The addition of 4 weight % TiAl 3 takes the overall titanium/aluminium concentration to the regime of the difficult to weld alloys such as C1023 which are subject to cracking when processed by ALM methods. The photomicrograph in FIG. 3 shows a sample of this material immediately after the ALM process. Distinct dark regions (such as the one near the centre of the image) containing high concentrations (analysis by Electron Diffraction Spectroscopy) of titanium and aluminium can be seen dispersed throughout the material. This demonstrates that these elements do not diffuse significantly during the very brief melt period imposed by the ALM process. The photomicrograph in FIG. 2 shows a further sample of the material which was subjected to a solution heat treatment subsequent to the ALM process. No such distinct regions of high aluminium/titanium concentration are visible. This indicates that these elements can indeed be successfully dispersed into the bulk by solid-state diffusion during such a heat treatment. Furthermore no evidence of cracking has been observed despite the high levels of gamma prime forming elements present. | A method of forming an article includes forming a layer of a mixture of at least two distinct metal powders selected such that when combined they are chemically in the proportions of a superalloy containing a gamma prime phase, and fusing the powders locally without diffusion to define the shape of a part of the article such that the materials of the distinct metal powders remain substantially chemically segregated forming regions of different chemical composition. The method further includes repeating the forming and fusing until the derived article is formed, and heat treating the finished article such that at least one of the distinct separate materials diffuses to form a gamma prime phase containing superalloy with the other. | 8 |
FIELD OF THE INVENTION
[0001] The present invention relates to a personal loader device, essentially a compact self-propelled personal construction vehicle for performing construction and landscape tasks. The personal loader, which may be controlled by an individual operator in either a walk behind or ride along mode, can push, lift, move, load and unload, in both horizontal and vertical directions, hundreds of pounds of materials as necessary. For instance, heavy snow, dirt and other landscape and construction materials can be handled and maneuvered through tight work spaces. The loader is extremely manipulatable and dexterous with heavy material in small areas and can be quickly and radically changed through numerous attachment accessories such as dozer blades, sweepers, rakes, buckets, grapples and pallet forks.
BACKGROUND OF THE INVENTION
[0002] Skid-steer loaders, well known in the construction industry, are versatile, powerful machines used extensively for material handling purposes. Skid-steer loaders, the term “skid-steer” refers to the loader's steering, utilize four hydrostatically driven wheels and allow the machine to turn within its own wheel base by breaking or counter-rotating each side-similar to a military tank track control.
[0003] There are known in the industry a number of different types of light-duty, skid steer loaders called mini-loaders. These machines are significantly smaller than typical construction skid-steer loaders but may not be correspondingly less expensive. Attachment products are also available for landscaping, ground maintenance, turf, light industrial, small contracting and small farming industries. These machines are somewhat of a scaled-down version of a skid-steer device designed to work in confined constructions areas.
[0004] The known mini-skid-steer devices accommodates the small contractor and rental market and although these light-duty, skid-steer loaders are smaller, they are still too large and expensive for personal home use, storage or easy transportation. The skid-steer wheel control acts in general like a tank track, i.e. one side is locked up, or skidded, while the others continue to rotate. This steering control tends to tear up the turf or ground on which the skid-steer vehicle is operating making such vehicles impracticable for personal home use in a garden, lawn or anywhere that the surface or ground should remain relatively undisturbed. Additionally, skid-steer drive and steering systems are expensive to service and repair must be performed generally by skilled experts.
[0005] Garden tractors are also well known in the art and can be designed for use with a front blade for light dozing work, for instance with snow and/or a snow thrower for the same purpose. Larger garden tractors have substantial horsepower and sturdy frames for such ground engaging attachments as tillers, dozer blades, small backhoes and other useful accessories. While garden tractors offer substantial abilities to mow and do light garden work, they do not have any vertical lifting capability and are not useful as a loader, or a digger and have poor ground clearance, large turning radiuses and cumbersome attachment methods.
[0006] OBJECT AND SUMMARY OF THE INVENTION
[0007] Wherefore, it is an object of the present invention to overcome the above mentioned shortcomings and drawbacks associated with the prior art.
[0008] An object of the present invention is to provide an efficient and economical device for personal and home landscape and construction use which augments the operator's ability to perform relatively heavy earth and materials moving projects around the home or workplace.
[0009] Another object of the present invention is to provide such device at substantially lower cost than the products currently available on the market.
[0010] A further object of the invention is to provide an easily controllable and maneuverable loader work device which enables a operator to maneuver in tight spaces and perform intricate maneuvers with heavy material handling capability.
[0011] An even further object of the present invention is to provide extreme maneuverability with loads without significantly disturbing the surface or ground over which the loader device is operating for instance during turning and maneuverability operations.
[0012] Yet another object of the present invention is to provide a plurality of attachments which can be easily removed or attached to the personal loader in order to facilitate the undertaking of numerous projects.
[0013] A still further object of the present invention is to provide a personal contracting or home gardening device which is capable of not only horizontally moving material, but also vertical material handling specifically for loading or dumping purposes.
[0014] The present invention also relates to a personal loader for assisting an operator in materials handling tasks comprising a frame supported by at least three wheels, at least one of the wheels being a powered drive wheel and at least one of said other wheels being a steerable wheel, an engine supported on the frame for driving a hydraulic pump and the at least one powered drive wheel, a hydraulic control regulating the hydraulic pump actuation of at least a first hydraulic circuit powering a vertically moveable primary accessory control means and a second hydraulic circuit providing angular rotational capability to a secondary accessory control means, and a control handle for steering the loader, the control handle having manual actuatable inputs for operation of the hydraulic control and the at least one powered drive wheel.
[0015] The present invention also relates to the personal loader as set forth above wherein the at least one powered drive wheel is a pair of fixed position drive wheels, each of the pair of drive wheels being driven by an associated first and second wheel motor which may be one of individually braked and driven relative to the other wheel motor.
[0016] The personal loader is generally a three or four wheeled device driven by an engine or motor and provided with a 2-wheel drive unit having a simplified hydrostatic differential transmission which allows the device to turn quickly within its own wheel base without the inherent high cost of skid-steer technology. Other drive trains for instance individual wheel motors which can be driven or braked individually relative to one another may also be used. The personal loader can be provided with a front pair of drive wheels and a pair of rear steerable wheels or a single rear steerable wheel. The loader may also be provided with the rear wheel or wheels being directly steered via known steering linkages and power assist steering mechanisms or in the alternative either a single or pair of castor type wheels which are not directly steered but are indirectly steerable by the operators maneuvering of the loader. The loader includes a frame supported by the wheels and a control handle for providing operational control over the loader. The control handle is located within easy reach of an operator riding or walking substantially directly behind the loader.
[0017] The engine is separately connected to the differential transmission unit for drive and a hydraulic pump for providing appropriate pressurization and de-pressurization to a hydraulic system operating the hydraulically controlled loader mechanism system. An operator walking or standing behind the machine and within reach of the control handle may cooperatively control the vehicle speed and steering as well as the hydraulic system mechanism manipulation via a series of manual controls on the control handle. Alternatively, or in combination therewith, a series of pedals can also be provided for the operator to utilize.
[0018] A number of different work tool attachments, for example a bucket loader, may be readily attached to the front end of the loader. Specifically a desired work tool attachment is connected with a pair of hydraulically controlled loader arms, and the work tool attachment is controlled in both a vertical and horizontal direction, as well as in a leveling function via the operators actuation of the hydraulically controlled loader arms. Balancing of the work tool attachment and any load therein is provided with respect to the loader about a rotational axis of the front drive wheels. In essence a fulcrum point is established substantially about the front drive wheels to ensure that maximum traction is provided to the drive wheels at all times and an appropriate balance point is provided for safely and effectively balancing the loader and any load applied through operation of the attachment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The invention will now be described, by way of example, with reference to the accompanying drawings in which:
[0020] [0020]FIG. 1 is a side elevational view of the personal loader showing the loader mechanism in an upper and an alternative lower positions;
[0021] [0021]FIG. 2 is a block diagram of the hydraulic control system;
[0022] [0022]FIG. 3 is a side elevational view of another embodiment of the personal loader device;
[0023] [0023]FIG. 4 is a top planar view of the 4-wheel personal loader device;
[0024] [0024]FIG. 5 is a top planar view of the 3-wheel personal loader device;
[0025] [0025]FIG. 6 is a top planar view of a bucket attachment for the personal loader device;
[0026] [0026]FIG. 7 is a rear view of the bucket attachment disclosing the attachment mechanism;
[0027] [0027]FIG. 8 is a close up view of the accessory attachment mechanism connected to the hydraulically operated loader arm; and
[0028] [0028]FIG. 9 is a side cross-sectional view of the accessory attachment matingly engaged with the attachment mechanism.
DETAILED DESCRIPTION OF THE INVENTION
[0029] Turning now to FIG. 1, a brief description concerning the various components of the present invention will now be briefly discussed. As can be seen in this embodiment, the personal loader 1 is described in general.
[0030] The personal loader 1 is comprised generally of a frame 10 supported by a pair of front drive wheels 2 and, as will be discussed in further detail below, either a single or a pair of rear steerable wheels 8 . The loader 1 is guided via a control handle 12 by the operator for purposes of steering, drive and hydraulic control over the personal loader 1 . The operator may stand on a support platform if provided in certain embodiments, or may walk behind the personal loader 1 as shown to provide guidance for the loader 1 .
[0031] The frame 10 supports an engine 50 connected to a differential transmission 54 and a hydraulic pump 52 . The differential transmission 54 is connected to a main power take off of the engine 50 to provide a power drive to the front wheels 2 of the personal loader 1 . The engine 50 powers the hydraulic pump 52 through a secondary power take off which operates the mechanical hydraulic system 60 to be described in further detail below.
[0032] The frame 10 is provided with a pivot axis P about which loader arm or arms 30 are controlled. The loader arms 30 , of which there are usually provided a pair, although a single loader arm is also a viable option, each have a pivot end 32 which are each attached to the main pivot axis P of the frame 10 and controlled in their rotation about the pivot axis P via the hydraulic system 60 as demanded by the operator through the control handle 12 . Each loader arm 30 also has a free end 34 which is provided with a universal attachment mechanism 20 . The attachment mechanism 20 is pivotally attached to the loader arms 30 and pivots about a rotational axis PA defined by the relative alignment of the separate free ends 34 of the pair of loader arms 30 .
[0033] It is to be appreciated that the hydraulic system 60 can be provided with a self balancing or leveling feature which automatically controls the free ends 34 of the loader arms in order to provide relative leveling of a load supported by the arms 30 with respect to the ground upon which the loader 1 is operating. In other words, rotational axis PA is adjusted relative to the ground to remain substantially parallel with respect to a constant horizon line. In embodiments without such a automatic self leveling feature, in some instances the operator may have to provide leveling of the attachment load by separately controlling the loader arms 30 . As the necessity for leveling and mechanics of performing such operations are well known in the art, no further discussion is provided.
[0034] The elevation control of the free end 34 of the loader arms 30 and the relative rotation of the attachment mechanism 20 are both controlled via the hydraulic system 60 through the operator's operation of the control handle 12 . In combination with the steering and drive control, such vertical and horizontal control is necessary over any attachment 80 to the loader 1 to provide for balancing, dumping, scooping, cutting, drilling, sweeping or scraping and other tasks as required in small loader and light construction use.
[0035] The critical function of balancing the loader 1 with respect to a variable load being applied to the work tool attachment accessory 80 at the free ends 34 of the loader arms 30 is accomplished by providing a fulcrum or balance point about the front drive wheels 2 of the loader 1 . With the fulcrum or balance point being substantially co-linear with the front wheel rotational axis 4 , the center of mass of the loader 1 is thus provided between the front and rear wheels. This fulcrum or balance point is accomplished by the relative rearward locating of the center of mass of the loader 1 with respect to the rotational axis 4 of the front wheels 2 , and the relative frontwards application of any load applied through the accessory 80 relative to the rotational axis 4 of the front wheels 2 .
[0036] With the balancing effect of the loaders rearward center of mass and any frontwards applied load to the attachment 80 about the balancing point or fulcrum, as can be appreciated, the front wheels 2 are thus provided with a maximum amount of traction due to both the frontward load and rearward center of mass having a vertical force component acting relatively downwards through the fulcrum balance point and via the front wheels 2 provides such a maximum traction force to the front wheels 2 .
[0037] Certain attachment tools 80 , such as the bucket loader attachment 80 shown, may be directly controlled through hydraulic control of the loader arms 30 and the relative rotation of the attachment mechanism 20 . Certain other attachment tools, for instance a rotating sweeper or an auger must be provided with an auxiliary hydraulic line from the loader 1 for powering an attachment tool motor which is generally integral with the attachment tool to provide for instance such rotational capability to the attachment as necessary. A further description of such an auxiliary attachment control is provided below.
[0038] A first embodiment of the present invention will now be discussed in greater detail. The steering and maneuverability of the personal loader 1 is of critical importance, and therefore, the loader 1 must be capable of substantially turning within a particularly tight radius of curvature. The front wheels 2 are, as discussed above, driven via a simplified hydrostatic differential transmission. This type of transmission allows for relative rotational speed differences between the front drive wheels to facilitate turning of the loader 1 . This type of transmission can also allow different relative rotational directions between the front drive wheels to provide even further facilitation of reduced turning radius.
[0039] The rear wheels 8 are the steering wheels for the loader and capable of rotation about a vertical axis VA relative to the front drive wheels 2 . These wheels 8 may be essentially what are known as turf wheels having a less aggressive tread so that in combination with the steerable rear wheel feature significantly minimize damage to the ground from steering operations.
[0040] The rear wheels 8 of the first embodiment are castor wheels. Each rear wheel 8 , whether a single wheel or a pair is utilized, is provided with an individual horizontal rear axle which is connected to and supports the frame 10 about a vertical axis VA. The horizontal axle of course provides for conventional horizontal wheel rotation thereabout to permit loader movement along the ground. The vertical axis VA to which the horizontal axle is attached permits a full 360 degree vertical rotation of the wheel or wheels about the vertical axis VA, independent from one another where a pair of wheels 8 are provided, thus allowing the rear wheels 8 to rotate into any angular position relative to the front drive wheels 2 . The castor wheels design provides extreme maneuverability in tight spaces and difficult locations as is often found in construction sites and personal residences.
[0041] In the present embodiment where castor wheel or wheels 8 are provided it is to be appreciated that in order to provide steering control the loader 1 , the operator must walk on the ground behind the loader and steer the loader through a fixed position control handle 12 . The control handle 12 is rigidly affixed to the frame and no direct steering mechanism or linkage is provided between the rear castor wheel(s) 8 and the control handle 12 . Thus, an operator in the walk behind embodiment could manipulate and manually steer the loader 1 , including the frame, hydraulic system and attachments via the relative positioning attained by appropriate maneuvering of the loader 1 via the rear castor wheel(s) 8 and the front wheels 2 , well within the loader's own wheel base. This maneuvering is made easier due to the fulcrum or balance point of the loader 1 being about the front wheels 2 and thus the castor wheel or wheels can be more easily aligned to maneuver the loader 1 .
[0042] [0042]FIG. 2 diagrammatically shows the control handle 12 which in addition to providing steering control may also provide a series of inputs for instance a manual throttle 3 for controlling the speed and drive of the front wheels 2 ; and a series of loader arm controls including at least an elevational control 5 , and an attachment accessory mechanism angle control 7 which through the hydraulic control 60 operates the mechanical loader arms 30 and the attachment mechanism 20 for the cutting, pushing, dumping, loading and unloading operations as required by the operator. An automatic self leveling feature may be provided or a manual control 9 , and an auxiliary attachment control 13 may also be provided on the control handle 12 for such a feature.
[0043] Thus, as is readily apparent to those of ordinary skill in the art, in either the walk behind mode or the operator supported mode embodiment, the operator can thus provide via the control handle 12 directional control of the loader 1 and mechanical hydraulic control, i.e. vertical and angular control over the loader arms 30 and accessory attachment control via the auxiliary work tool attachment control 13 as well as horizontal control via the loader speed control throttle 3 . All these operator inputs may be provided through conventional control mechanisms such as twist throttles, knobs, buttons or levers associated with the control handle 12 .
[0044] Turning to FIG. 3 the hydraulic control system 60 of the present invention is generally described. Each loader arm 30 is controlled by the hydraulic system 60 which comprises, for each loader arm 30 , an elevation control hydraulic cylinder 62 and an attachment mechanism control cylinder 72 . The elevation control hydraulic cylinder 62 is pivotally attached at a first end 63 to the frame 10 and at a second end 64 to a pivot point on the loader arm 30 . The operator controls the pressure to the elevation control hydraulic cylinder 62 through the corresponding input 5 of the control handle 12 where an increase in pressure to the elevation control hydraulic cylinder 62 extends the hydraulic cylinder 62 thus elevating the loader arm 30 .
[0045] The attachment mechanism 20 rotatably connected to the free ends 34 of the loader arms 30 is controlled in its rotation relative to the loader arm 30 via an angle linkage 70 which is controlled by the attachment angle control hydraulic cylinder 72 having a first end 73 connected to the linkage 70 and a second end 74 attached to a portion of the loader arm 30 substantially adjacent the connection of the elevation control hydraulic cylinder 62 first end 64 . The attachment angle control hydraulic cylinder 72 is also controlled via input 7 by the operator at the control handle 12 where the increase or decrease in pressure as demanded by the operator and applied via the hydraulic pump 52 varies the angle A of the attachment mechanism 20 and thus the attachment 80 on the personal loader 1 relative to the loader arms 30 .
[0046] As set forth above angular control over the accessory attachment 20 is provided via the accessory attachment hydraulic cylinder 72 acting through the accessory attachment linkage 70 . The linkage 70 includes a second pivot point PA2 on the accessory attachment 20 which is spaced from the pivot point PA. A double link 75 having a first end connected to the second pivot point PA2 and a second end connected to the control arm 30 are connected at a middle joint 77 to the first end 73 of the attachment hydraulic cylinder 72 which when actuated provides substantial mechanical advantage to control the rotation of the accessory attachment 20 about the pivot point PA.
[0047] It is to be appreciated that any number of attachment accessories 80 can be quickly attached to and detached from the personal loader 1 via the attachment mechanism 20 . In particular, a primary attachment accessory 80 could be a bucket as shown for scooping, moving and handling heavy bulk materials. Numerous other attachment accessories are contemplated as well, dozer blades for cutting and scraping, forks for moving pallets or boxes, etc.
[0048] Other work tool attachment accessories, for instance an auger or a rotating sweeper brush (not shown) may also be attached to the loader arms via the attachment mechanism 20 . These attachment accessories are usually provided with a hydraulic motor 63 , see FIG. 2, to supply the necessary rotation or power to the work tool attachment. The hydraulic motor 63 of these work tool accessories is provided with power via an auxiliary hydraulic control line 61 which connects between the hydraulic motor 63 of the work tool accessory and hydraulic pump 52 . This auxiliary control line 61 is diagrammatically shown in FIG. 2 and is controlled via the hydraulic control 60 by the auxiliary attachment control 13 on the control handle 12 . Therefore an operator in coordination with the other series of hydraulic controls on the control handle can also control the auxiliary attachment control when necessary.
[0049] As shown in FIGS. 3 and 4, the rear castor wheel or wheels 8 shown in the first embodiment, may in other embodiments be replaced with directly steerable wheels 8 . The steering and maneuverability of the personal loader 1 is of critical importance, and therefore, the loader 1 must be capable of substantially turning within a particularly tight radius of curvature. Alternatively to the provision of steerable castor wheels which are not directly but indirectly steered, the rear wheels 8 may be directly controlled via a conventional mechanical advantage tie rod steering mechanism 11 . Each rear wheel 8 is provided with an individual rear axle supported on the frame and connected to the control handle 12 via the tie rod mechanism 11 . The tie rod mechanism 11 and the individual axles of each rear wheel 8 provide at least full 180 degree pivot angle for the rear wheels 8 . The full 180 degree rotation allows the rear wheels 8 to rotate to a position perpendicular with respect to the front drive wheels 2 , which provides extreme maneuverability in tight spaces and difficult locations as is often found in construction sites and residences. Additionally, with such a full rotation and pivot angle of the steerable wheel or wheels relative to the drive wheels, no harm is done to the surface upon which the loader 1 is turning.
[0050] The control handle 12 can be made to be rotatable relative to the frame and connected with the steering linkage 11 . As there are many types of steering linkages which could readily directly connect the control handle 12 with the rear wheels 8 , no further description is provided. However, it is also to be appreciated by those skilled in the art that a power assisted steering mechanism could also be provided. For instance, a hydraulic power steering assist can be provided by a conventional rotary pump driven by the loader engine 50 , and through a rotary valve providing the necessary hydraulic power assist to the operator when the appropriate turning force on the control handle 12 is provided. The rotary pump and valve provides an output which assists the operator in rotation of for instance a worm gear of the steering gear communicating with the axles. As such hydraulic power steering systems are also well known in the art, no further discussion is provided herein.
[0051] With such a direct steering method, it is also possible to have an operator ride on a platform 14 as shown in FIG. 4. The operator has the choice of either riding on the platform 14 or walking behind the loader, whichever way the operator can provide the best control over the loader 1 . Furthermore, any size tires may be provided for either the front or the rear wheel or wheels. In some instances for instance for work on grass, smaller, soft tires might be necessary to decrease damage to the grass or turf. At muddy construction sites it might be necessary to have the drive wheels provided with a large aggressive tread design. Such decisions are made by those of ordinary skill in the art based on terrain, weather and required use and as such no further discussion is provided.
[0052] Additionally, it is possible to have different combinations of drive and steerable wheels, for instance the rear wheels 8 could be provided to drive the loader and the front wheels being steerable, or in other cases a 4 wheel drive differential might be provided to supply drive to all wheels, with either the front or the back wheel(s) being steerable.
[0053] [0053]FIG. 5 depicts another embodiment of the present invention namely a personal loader 100 comprised generally of a frame 110 supported by a pair of front wheels 102 connected via front axle 104 and a single rear wheel 108 . The frame 110 includes an operator support platform 114 . The operator may stand on the platform 114 or in some instances may walk behind the personal loader 100 with the platform 114 folded up out of the way or removed from the frame 110 . Also, alternatively to the differential transmission 54 , the front wheels 102 may be driven by individual wheel motors 154 connected with each front wheel 102 as shown in FIG. 5. The individual wheel motors 154 can be each individually controlled, i.e. braked and/or driven, either forward or reverse by the operator to facilitate turning of the loader.
[0054] The frame supports an engine 150 connected to a hydraulic pump 152 and the individual wheel motors 154 . The engine 150 powers the hydraulic pump 152 which operates the mechanical hydraulic system 160 to be described in further detail below. The individual wheel motors 154 may be hydraulically driven and are connected between hydraulic pump 152 and the front wheels 102 to provide an individual wheel power drive to the front wheels 102 of the personal loader 100 .
[0055] [0055]FIGS. 6 and 7 show one type of accessory attachment 80 , namely a bucket loader, having a back plate 71 designed to matchingly engage with and being supported by the attachment mechanism 20 , 120 at the free end 34 , 134 of the loader arms 30 , 130 . A further description of the back plate 71 will be provided below.
[0056] Turning to FIG. 7, the attachment mechanism 20 , 120 attached to the loader arms 30 , 130 is provided with a face plate 21 having a front side 22 and a back side 23 , the back side 23 supporting a pair of manually actuated levers 24 , although it is conceivable that a single lever could be utilized as well. The levers 24 operate via a common mechanical link pin mechanism having an adjustment link 25 and an engagement pin 26 . Engagement pin 26 is operable in an engaged and a disengaged position via actuation of the levers.
[0057] In the engaged position an attachment accessory having the back plate 71 is mounted to the front side 22 of the face plate 21 as will be described below, and an operator, during engagement and disengagement operations, rotates the handles or the levers 24 and thus moves the engagement pins either into or out of holes 27 provided in the face plate 21 to engage respective holes in the back plate 71 . The face plate 21 is provided with the hole or passage 27 therethrough which the engagement pin 23 is moved via actuation of the levers. In the disengaged position, the pin 23 is removed from the hole 27 and in the engaged position extends all the way therethrough to affix the attachment accessory 80 to the face plate 21 .
[0058] Observing FIG. 8, each attachment accessory 80 is provided with the matching back plate 71 designed to matchingly engage with the front side 22 of the face plate 21 of the attachment mechanism 20 . The back plate 71 is provided with an upper lip 73 which is intended to engage an upper edge 28 of the face plate 21 . A matching hole or orifice 77 is provided in a matching lower portion of the back plate 71 through which the engagement pin 26 extends when the lever is rotated into the engaged position. Thus, as can be readily observed by one of ordinary skill in the art, the attachment accessory 80 is held in both vertical and horizontal privity with the face plate 21 . Such attachment mechanisms are well known and capable of being constructed in numerous ways. The importance of the present invention being that it is simple and may be manufactured to be readily compatible with any number of different accessories to be used in conjunction with the personal loader 1 .
[0059] Since certain changes may be made in the above described improved personal loader device, without departing from the spirit and scope of the invention herein involved, it is intended that all of the subject matter of the above description or shown in the accompanying drawings shall be interpreted merely as examples illustrating the inventive concept herein and shall not be construed as limiting the invention. | A three or four wheeled miniature personal loader device driven by an engine or motor and provided with a powered drive unit having a simplified hydrostatic differential which allows the device to turn quickly within its own wheel base. The personal loader is provided with a front pair of drive wheels and a pair of rear steerable wheels or a single rear steerable wheel. The loader may be provided with the rear wheel or wheels being directly steered via known steering linkages and power assist steering mechanisms or in the alternative either a single or pair of castor type wheels which are not directly steered but are indirectly steerable by the operators manual maneuvering of the loader. The engine is also connected a hydraulic pump for providing appropriate regulation of a hydraulic system operating the hydraulically controlled loader mechanisms. An operator walking or standing behind the machine and within reach of the control handle may control the vehicle speed and steering as well as the hydraulic system mechanism manipulation via a series of manual controls on a control handle. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to an apparatus, a method, and a program for generating a test script for functional testing in developing an information processing system.
BACKGROUND
[0002] A large number of efficient systems for a testing phase in information system development have been proposed.
[0003] For example, Japanese Unexamined Patent Application Publication No. 6-110733 discloses a test-case generating apparatus for generating a script file for testing programs and test data by combining program specifications with a standard script file. Japanese Unexamined Patent Application Publication No. 9-223040, Japanese Unexamined Patent Application Publication No. 9-223041, and Japanese Unexamined Patent Application Publication No. 9-223042 disclose a system-test supporting apparatus and the like configured to describe the specification of an application having a GUI section into a specification file or an information file and then to automatically generate a comprehensive test scenario. Japanese Unexamined Patent Application Publication No. 11-306046 includes a method for generating a test case from tabular functional specifications. Japanese Unexamined Patent Application Publication No. 2000-339193 includes a method for converting an operation specification from an operation specification and initial conditions to generate a test case. Japanese Unexamined Patent Application Publication No. 2004-280231 shows a method of verifying software in which a two-dimensional factor analysis table is generated from program input conditions and operating environment conditions, and then the input conditions and the operating environment conditions are combined to automatically generate a test script.
[0004] Various other methods for generating test cases from various unique definition information are shown in Japanese Unexamined Patent Application Publication No. 2002-259161, Japanese Unexamined Patent Application Publication No. 2002-366387, Japanese Unexamined Patent Application Publication No. 2004-220330, and Japanese Unexamined Patent Application Publication No. 2005-115582.
[0005] It is known in general information system development that the cost and risk of constructing systems are increased because of the ambiguity and incorrectness of specifications determined in a requirement defining phase. Since the 1970s, attempts to solve these problems have been made by strictly defining systems using formal specification languages. However, this is not broadly used because of high introduction cost. For a functional testing phase, regression testing with higher productivity is generally achieved by using automatic execution tools. However, test scripts for regression testing are generated with the recording function of the tools or by manual coding, posing the problem of taking much time and cost, and that it is impossible to verify whether automatically executed test scripts agree with the original functional requirements (specifications).
[0006] The methods of the foregoing patent documents need manual generation of specification files, tubular files, or state transition diagrams based on their unique definitions, which cannot support specification description methods using standardized formal specification languages or Universal Model Language (UML).
[0007] Accordingly, it is an object of the invention to provide, in system development using a standardized specification description method with a formal specification language or UML modeling description, a test-script generating apparatus for functional testing which ensures consistency with a specification determined by requirement definition and achieves an efficient method so as to generate a test script without high cost.
SUMMARY
[0008] The invention includes an apparatus for generating from a functional specification of software a test script for executing a functional test of the software. The apparatus includes: an input/output variable extracting section for extracting from a specification file describing the functional specification an input variable, an output variable, an input-variable type, and an output variable type for each runtime display screen generated by the software; a screen-transition extracting section for extracting screen-transition information from the specification file; and a test-script generating section for generating a test script for executing the functional test using the input variable, the output variable, the input-variable type, the output variable type, and the screen-transition information.
[0009] The apparatus may be configured such that, according to the screen-transition information, the test-script generating section generates, for the input variable, a test script indicative of an action corresponding to an object associated with the input variable; and for the output variable, a test script that compares text information displayed on a display screen that the software generates at runtime with an expected value determined from the output variable.
[0010] The apparatus may be configured such that the object includes a button (including a radio button and a list box), a text field, and a list box; and the action corresponds to a selection from a user click operation, a character-string input operation, or an operation of selecting out of a list.
[0011] The apparatus may be configured such that the test-script generating section optimizes the execution count of testing by finding, in a directed graph in which each edge represents screen transition, an edge path set including at least one edge path for each edge of the screen transition, in which a redundancy value is smaller than a predetermined value.
[0012] The apparatus may be configured such that the edge path set is found by a predetermined “depth-first-combination algorithm”.
[0013] The apparatus may be configured such that the test-script generating section finds an edge path set for executing the shortest screen transition according to a predetermined “Form-screen transition algorithm”, for testing any combination of Form elements.
[0014] The apparatus may be configured such that the specification file is described in Z language.
[0015] The apparatus may be configured such that the test-script generating section determines the order of priority for determining a type of an object associated with the input variable in the order of (1) an object type described in a predetermined property file, (2) a type name of the input variable, (3) link object type.
[0016] The apparatus may be configured such that the test script uses a runtime library that is called at the execution of testing of an application, so as to dynamically search for an object associated with the input variable in a browser displaying a test screen according to a type and an object name of the object.
[0017] The apparatus may be configured such that the specification file is described in a UML activity diagram.
[0018] The apparatus may be configured such that the UML activity diagram includes at least one UML element of a screen element, Form element, and a screen-transition element.
[0019] In brief, the apparatus of the invention can automatically generate a test script conforming to the functional specification by the following operations:
[0020] 1) extracting an input variable, an output variable, and the respective types of the variables from a specification file for each screen,
[0021] 2) extracting screen-transition information from the specification file; and
[0022] 3) executing the following processes from the top from one screen to another that appear in screen transition obtained in (2).
[0023] a) for the input variable, the apparatus generates a test script indicative of an action (clicking or a character set) corresponding to an object associated with the input variable;
[0024] b) for the output variable, the apparatus generates a test script that compares text information displayed on a screen with an expected value determined from the output variable.
[0025] The method of the invention supports a modeling description method using Z language, or a formal specification language, and UML as a standardized specification description method. However, other specification description methods (e.g., Vienna development method (VDM)) should not be excluded. The invention also provides an algorithm for generating a test script with little redundancy which covers all the paths between the nodes and edges in an effective graph in which the nodes represent the screens of software to be tested and the edges represent screen transition.
[0026] According to another aspect of the invention, there are provided a method for executing the function of the apparatus and a computer program having computer usable program code for generating a test script for executing the steps or algorithm of the method. According to yet another aspect of the invention, there is provided a program product including computer readable media that store the computer program.
[0027] The invention can provide an apparatus of generating a test script and so on which ensure consistency with the specification determined by requirement definition and achieves an efficient method so as to generate test scripts without high cost without using a unique-definition specification describing method in developing an information system using a formal specification language or a standardized specification describing method such as a UML modeling describing method. This ensures that the functional test reflects requirement definition and allows the specification to be used also for functional testing, thus reducing part of the cost for generation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The invention will now be described in further detail with reference to the drawings, wherein:
[0029] FIG. 1 is a functional block diagram of a test-script generating apparatus 10 according to a preferred embodiment of the invention;
[0030] FIG. 2 is a diagram showing an example of a simple schema named “Browse” according to a first embodiment of the invention;
[0031] FIG. 3 is a diagram showing a method for generating a script and a flowchart for the process of the same in the first embodiment of the invention;
[0032] FIG. 4 is a diagram showing the method for generating a script and the flowchart for the process of the same in the first embodiment of the invention;
[0033] FIG. 5 is a diagram of the system configuration in which a Z language editor is installed as Eclipse plug-in, and it is associated with RFT in the first embodiment of the invention;
[0034] FIG. 6 is a diagram showing a system configuration in which UML is used in describing a specification according to a second embodiment of the invention;
[0035] FIG. 7 is a diagram showing an example of the activity diagram of ULM in the second embodiment of the invention;
[0036] FIG. 8 is a diagram showing UML stereotypes and descriptions therefor in the second embodiment of the invention;
[0037] FIG. 9 is a diagram showing the execution count of screen transition in the second embodiment of the invention;
[0038] FIG. 10 is a diagram showing the dynamic search for a GUI object in the second embodiment of the invention;
[0039] FIG. 11 is a directed graph of screen navigation according to a third embodiment of the invention;
[0040] FIG. 12 is a diagram showing how Paths and Outputs change when algorithm 1 is applied to the directed graph of FIG. 11 in the third embodiment of the invention;
[0041] FIG. 13 is a diagram showing how Path and Outputs change when algorithm 2 is applied to the directed graph of FIG. 11 in the third embodiment of the invention;
[0042] FIG. 14 is a flowchart for algorithm 3 in the third embodiment of the invention;
[0043] FIG. 15 is a diagram showing differences in redundancy when the methods are applied to the directed graph of FIG. 11 in the third embodiment of the invention;
[0044] FIG. 16 is a diagram showing an example of an application screen having Form elements according to a fourth embodiment of the invention;
[0045] FIG. 17 is a diagram showing Form elements and the number of options in the fourth embodiment of the invention;
[0046] FIG. 18 is a flowchart for algorithm 4 in the fourth embodiment of the invention;
[0047] FIG. 19 is a diagram showing a difference in the count of screen-transition execution between the methods in the fourth embodiment of the invention;
[0048] FIG. 20 is a diagram showing an example of implementation in which design names and implementation names can be coresident in a configuration in which the presence of a data pool or entries in the data pool are not postulated in a fifth embodiment of the invention; and
[0049] FIG. 21 is a diagram showing an information processing unit 100 as a typical example of the hardware of the test-script generating apparatus 10 .
DETAILED DESCRIPTION
[0050] FIG. 1 is a functional block diagram of a test-script generating apparatus 10 including the above-described solving means according to a preferred embodiment of the invention. The apparatus primarily includes an input/output variable extracting section 2 , a screen-transition extracting section 3 , and a test-script generating section 7 . The apparatus further includes a controller (CPU) and a storage section (which are not shown). The apparatus may also include an input/output section to communicate with the operator of the apparatus or other systems and a communication control section. The configurations are merely examples; other variations having equivalent functions may be included. The apparatus is typically achieved by a computer such as a personal computer or a general-purpose computer; however, it may be achieved by another information processing unit having a microprocessor, a storage section, and appropriate input/output means.
[0051] The input/output variable extracting section 2 of the apparatus extracts an input/output variable 4 for use in a screen in the unit of screen by using the characteristics of the describing method of a specification file 1 of a system under test described by the developer, with the specification file 1 as input data. At that time, the input/output variable extracting section 2 extracts the input/output variable 4 and an input/output variable type 5 (the type of the input/output variable) corresponding thereto at the same time. A specific extracting method will be described for each embodiment of the specification description, to be described later.
[0052] A screen-transition extracting section 3 of the apparatus detects the information on each screen contained in the specification file 1 to extract screen-transition information 6 on the transition of the screens. A concrete extracting method will be described for each embodiment of the specification description, to be described later.
[0053] A test-script generating section 7 of the apparatus generates a test-script file 8 for automated functional testing using the input/output variable 4 and the input/output variable type 5 output from the input/output variable extracting section 2 and the screen-transition information 6 output from the screen-transition extracting section 3 as input data. An automated-testing executing tool 13 tests an application 12 by executing the generated test-script file 8 . A runtime library 11 called from the test-script file 8 can dynamically search for an object associated with the input variable at the execution of testing in a browser on which a test screen is displayed using the object type and the object name as key. According to an embodiment of the invention, while the test-script file is installed so as to be used as an input for Rational Functional Tester (RFT)™ which is a known automated-testing execution tool, the automated-testing execution tool is not limited to that. The conditions that the automated-testing execution tool 13 has to meet will be described later. The invention will be specifically described herein with reference to embodiments.
[0054] First Embodiment: Implementation Example of Using Z as Formal Specification Language. Here an implementation example using Z as a formal specification language and the above-mentioned RFT as an automated-testing execution tool for functional testing will be described. Among formal specification languages, Z is used most frequently, which is also standardized by ISO. Z has a notation based on the theory of sets and a predicate logic, whose specification is described in schemas. FIG. 2 shows an example of a simple schema named “Browse”. This example shows such a specification that when a specific book is selected from a list of books, its summary is displayed. The schema in the description of FIG. 2 is indicated by numeral 23 . The upper part 21 of the schema 23 indicates a declaring section in which variables and functions are declared. For example, the fact that variable x is an element of set X is expressed as “x:X”. Here, “?” at the end of the variable name “book” indicates that it is an input variable, and “!” at the end of the variable name “abstract” indicates that it is an output variable.
[0055] Since the schema declaring section 21 declares a variable in the form of “variable name:type name”, the type of the variable can be known. Furthermore, a combination of schemas “schema calculus” is defined, one of which is “schema composition”, which can describe a state transition across a plurality of schemas. In the example of FIG. 2 , the part indicated by numeral 24 shows schema composition. In this embodiment, it is assumed that schemas are defined in the unit of screen (Z language itself does not have such limitation). Thus, screen transition can be described by schema composition 24 .
[0056] As has been described, Z allows determination whether a variable is an input variable or an output variable from the variable name described in the schema declaring section 21 . Its fundamental concept is that, for input variables, a script indicative of an action to a corresponding object is generated, and for output variables, a script to compare text information displayed in a browser with an expected value corresponding to the output variable is automatically generated. However, since there is a semantic gap between the specification described in Z and the programming model of RFT, it is necessary to solve the four subjects described below. They are described in the following (A) to (D).
[0057] (A) Screen-Transition Derivation Rule: The specification described in Z does not specify by what screen separation and screen transition it is achieved. Therefore, it is coped with by making the following rules:
[0058] Rule 1: Bring a schema and a screen into one-to-one correspondence.
[0059] Rule 2: Display screen transition by a schema composition.
[0000] The schema composition is a kind of a schema operation. For example, if schema A causes the state of the system to transition from S 1 to S 2 and causes schema B transition from S 2 to S 3 , schema C which is a composition of the two schemas is described as [Expression 1], which causes the state of the system transition from S 1 to S 3 .
[0000]
C
≅
A
*
B
[
Expression
1
]
[0060] Since schemas A and B correspond to screens AP and BP, respectively, under rule 1, it can be interpreted that schema C corresponds to screen transition AP to BP.
[0061] (B) Mapping of Input Variable and Object Type: It cannot be determined from the input variable name that appears in the declaring section of the specification with what type of object it is installed. For example, it cannot be determined whether the variable, book, in FIG. 2 indicates inputting the name of a book into the text field on the browser or clicking the name of the book displayed as a link. To solve the problem, we have adopted a method of preparing a property file and describing the mapping of variable names and object type names in the form to be described later. However, since it is complicated to describe such a correspondence relation of all the input variables, we have devised a rule to be applied when there is no entry in a property file. This will be described later in a fifth embodiment.
[0062] (C) Handling of Session information: For Web applications, in order to hold session information, a session key is stored in a cookie etc. The session key needs to be described as an input variable for specifications using Z language. In contrast, information about a session key which does not appear in the operation of the user cannot be described because RFT script corresponds to user operation. In order to solve this problem, a script is not generated for an input variable mapped to an object type called Session. An object type to which an input variable is mapped is determined in the following order of priorities.
[0063] 1) An object type described in property file
[0064] 2) An object type with the same name as a set name when the set name to which the input variable belongs is any of Session, Submit (it corresponds to submit button) or Password (it corresponds to password field)
[0065] 3) An object type called Link (it corresponds to an anchor tag, which is used as a default).
[0066] (D) Method for Specifying Object Runtime: Even if the object type is determined, it cannot be known where of the Document Object Model (DOM) tree the object itself is present. Therefore, the object is dynamically searched for by using Application Program Interface (API) provided by RFT. The key for search includes the object type and the names of the link and the button. Since the latter is generally different from the variable name described in the specification, the input variable name and the implementation name are mapped using the data pool of RFT. The data pool is used also for mapping output variable names and expected values to achieve separation of the test script from data.
[0067] Means for solving the above problems will be described hereinbelow more specifically.
[0068] (1) Object Type and control.properties File: From the input variable name in the declaring section of the schema, it cannot be determined by what kind of control (a button, a text field, etc., hereafter also called an object type) it is implemented. Therefore, mapping of input variable names and object type names is described in a property file named control.properties in the following form.
[0069] Schema name, input variable name=object type name
[0070] For example, Confirm.user=Text. Examples of the object type are as follows:
[0000]
TABLE 1
Object Type
Description
Action
Session
Indicative of Session key
N/A
that does not correspond to
GUI
Submit
Corresponding to Submit
Click
button
Text
Corresponding to test field
setText
Password
Corresponding to pass word
setText
field
Link
Corresponding to anchor tag
click
[0071] A script is not generated for an input variable mapped to Session. This is because although a session key must be described as an input variable in Z language, no session key appears in a script on RFT (because it does not correspond to user operation).
[0072] (2) Method for Determining Object Type: Since it is complicated to describe the mapping of all the input variables to the object types in the control.properties file, the object type is determined in the following order of priority. This eliminates the need for describing the mapping in the control.properties file in most cases.
[0073] 1) An object type described in control.properties
[0074] 2) The same object type as the type name when the type name to which the input variable belongs is any of Session, Submit, and Password.
[0075] 3) Link object type (used as a default)
[0076] (3) Dynamic Search for Object Corresponding to Input Variable and Driving of Action: To describe a generated script in a simple form, wrapper class is generated using RFT API to each GUI object. For example, when Submit button expressed by an input variable, order, is clicked, the description is as follows:
[0000]
//initialization
Submit submit = new Submit (this);
// body
:
:
submit, click (“order”);
[0077] First, an object corresponding to “order” is dynamically searched for in the browser in the click method of Submit class. The key for search includes an object type and a button name. Here although “order” is an input variable name appearing in the specification, it is conceivable that the button name for implementation is generally different. Accordingly, the data pool of RFT in Submit class is accessed to obtain implementation name. Then, click method is called for the found object.
[0078] (4) Comparison between Expected Value Corresponding to Output Variable and Text Displayed on Browser: An expected value corresponding to the output variable and the text displayed on the browser are compared. In the example of the schema in FIG. 2 , abstract is an output variable. An expected value therefor is described in the data pool of RFT to achieve the separation of the script from the data. To obtain the text displayed on the browser, a wrapper class called HtmlText is generated, in which an object of a class “Html.HtmlDocument” is dynamically searched for. Its text attribute is a text displayed on the browser. Comparing the expected value and the measured value using the VerificationPoint class of RFT allows test results to be automatically obtained at the end of testing.
[0079] (5) Test Script Generating Algorithm: Suppose that each screen is expressed as schema Ai (i=0 to n−1). Their schema composition C=A 0 o A 1 o, to o An−1 indicate screen transition A 0 →A 1 → . . . →An−1. The algorithm for generating a test script corresponding to is as follows:
[0080] The following operation is executed from i=0 to n−1.
[0081] 1) Determine the object type of all the input variables Ai by the method (2). (for example, a button)
[0082] 2) Determine actions for the determined objects. (for example, a click action for a button)
[0083] 3) Generate the script indicated in (3). When there are two or more input variables, generate the script for Link or Submit last.
[0084] 4) Compare the expected value with the actual text for output variable Ai by the method of (4).
[0085] FIGS. 3 and 4 show the method for generating a script and the flow of the process using the same. Referring to FIG. 3 , in step S 31 , mapping of the objects is executed with reference to the property file. In step S 33 , an input variable is extracted to generate an action for the object. For an output variable, the output of the application is compared with the expected value in step S 32 . As a result, a functional test script 34 is generated. Referring next to FIG. 4 , in step S 34 , the specification name and the implementation name are mapped with reference to a data pool 35 . Step S 34 is executed by the runtime library 11 of FIG. 1 . In step S 35 , a dynamic search for the object using the API of RFT is executed using the object type and the name as search key.
[0086] (6) Verification of Effectiveness: To verify the effectiveness of the embodiment of the invention, a Z language editor was installed as Eclipse plug-in and was associated with RFT. FIG. 5 shows the system configuration. A class library 56 corresponds to the runtime library 11 in FIG. 1 , which is the wrapper class described in (3) and (4). Executing a test script 55 described in Java™ allows automated testing of Web applications. The script is described as an action (click etc.) for DOM objects (links or buttons) on the browser. An RFT 54 can describe the script in the form of an action to an object and has an API for dynamically searching an object. For verification, the specification of a sample application was described in Z language, and a functional test script for the RFT 54 was automatically generated by an action called from an editor menu.
[0087] The first two lines of the following script correspond to the schema 23 in FIG. 2 . Executing the script on the RFT allowed the behavior of the application to be reproduced, allowing automatic comparison between the text displayed on the browser and an expected value.
[0088] link. click (“book”)
[0089] HtmlText. test (“abstract”)
[0090] submit. click (“order”)
[0091] htmlText. test (“prompt”)
[0092] textInput. setText (“username”, “userValue”);
[0093] submit. click (“confirm”);
[0094] htmlText. test(“accept”)
[0095] In the first embodiment, Z language is used as a formal specification language, and RFT is used as an automated testing tool. The format specification tool may not be limited to Z language but another language such as VDM may be used. Here conditions for the formal specification language are as follows:
[0096] 1) Specification can be described in screens.
[0097] 2) Screen transition can be described with a combination of the specifications described in screens.
[0098] 3) An input variable and an output variable can be specified.
[0099] 4) The type of an input variable can be found.
[0100] The automated testing tool for applying the invention is not limited to the RFT but any testing tool that meets the following conditions can be applied.
[0101] 1) The script can be described in the form of an action to an object.
[0102] 2) A GUI object can be found by assigning the attributes (the class, label, etc.) of the object to keys.
[0103] Although many methods for extracting programs from formal specifications have been researched, they inevitably need manual operations because of difference in abstraction between specifications and programs. The embodiment of the invention has proposed a method for automatically generating a functional test script from formal specifications by connecting the specifications with functional tests. This has become possible because the abstraction levels of specifications and functional tests are principally near each other even with the above-described gap. Such s method has not been known and can be developed variously. For example, a plurality of test scripts including normal and error systems may be generated or a script for boundary value testing may be generated using a plurality of data pool records.
[0104] A second embodiment in the case where UML is used in describing a specification will now be described.
[0105] FIG. 6 shows a system configuration in which UML is used in describing a specification. In this configuration, a UML activity diagram (indicated by numeral 66 ) is used to describe the specification, and RFT6.1.1 (numeral 64 ) is used as an automated testing tool as in the foregoing embodiment. Here, an activity diagram generated on Ellipse ( 65 ) using a UML 2.0 editor ( 61 ) is analyzed by a test-script generator plug-in 63 via a transformation API (numeral 62 ) to generate a test script 67 . The RFT6.1.1 (numeral 64 ) executes the test script 67 with reference to a helper Java class 68 (corresponding to the runtime library 11 in FIG. 1 ) and an RFT data pool 69 to execute testing. Hereinafter, the details will be described.
[0106] (1) Method for Describing Specification: First, the specification is described in the UML activity diagram. FIG. 7 shows an example of the activity diagram, in which the actions of the ULM elements in the activity diagram are as follows:
[0107] —CallBehaviorAction
[0000] Individual screens: Home 70 , Browse 74 , etc. in FIG. 7
[0108] —InputPin
[0109] Form elements such as a text field: title 79 , description 80 , etc. in FIG. 7
[0110] —Control Flow
[0000] Screen transition: browse 81 , category 82 , etc. in FIG. 7
[0111] A UML profile is defined and UML elements are extended according to the following stereo types.
[0112] —A Stereotype for CallBehaviorAction:
[0113] any (any screen), noTest (indicating that the comparison between the text information of the screen and an expected value is not made, that is, it is not to be tested)
[0114] —Stereotype for InputPin:
[0115] textField (indicating a text field), select (indicating a list box), radioBntton (indicating a radio button), etc.
[0116] —Stereotype for ControlFlow:
[0117] link (Indicating an anchor tag), submit (indicating a submit button)
[0118] FIG. 8 shows the UML stereotypes and descriptions thereof.
[0119] (2) Dynamic Search for Object and Drive of Action: To describe a generated script in a simple form, wrapper class is generated using RFT API to each GUI object. For example, when submit button, go, is clicked, the description is as follows:
[0000]
//initialization
Submit submit = new Submit (this);
// body
:
:
submit, click (“go”);
[0120] First, an object corresponding to “go” is dynamically searched for in the browser in Submit class. The key for search includes an object type and a button name. Here although “go” is a submit button name appearing in the specification, it is conceivable that the button name for implementation is generally different. Accordingly, the data pool of RFT in Submit class is accessed to obtain implementation name. However, since it is complicated to register implementation names to all the specification names in the data pool, we has devised so that the specification name is used as it is when it is not registered in the data pool. Then, click method is called for the found object.
[0121] (3) Comparison between Expected Value Displayed on Screen and Text Displayed on Browser: An expected value displayed on the screen and the text displayed on the browser are compared. For example, referring to FIG. 7 , an expected value for the Browser screen is described in the data pool of RFT to achieve the separation of the script from the data. To obtain the text displayed on the browser, a wrapper class called HtmlText is generated, in which an object of a class “Html. HtmlDocument” is dynamically searched for. Its text attribute is a text displayed on the browser. Comparing the expected value and the measured value using the VerificationPoint class of RFT allows test results to be automatically obtained at the end of testing. Since it is complicated to input all the characters displayed on the browser as an expected value, the expected value can also be input by normal expression.
[0122] (4) Algorithm for Generating Test Script in which All ControlFlow is Passed: The following algorithms (4-1) and (4-2) are executed continuously to generate a test script in which all ControlFlow on the activity diagram is passed at least one time.
[0123] (4-1) Generating Plural Test Script by Breadth-First Search:
[0124] 1) Obtain an initial test script <Home> by starting from the screen (in the case of FIG. 7 , Home) directly after the starting end of the activity diagram.
[0125] 2) The following operation is executed by the number (referred to as size) of Control-Flow that are not passed among the ControlFlow starting from the end of the test script. Here take it into account that the screen having a stereotype <<any>> 71 indicates any screen. Therefore, ControlFlow starting from Home includes home, browse, and search.
[0126] 3) The test script is copied as many as the number of size, to each of which the screen at the end of ControlFlow is added. These ControlFlow are marked as being passed, and the process returns to 2).
[0127] 4) Process for all the test scripts is finished when there is no unpassed ControlFlow starting from the end screen.
[0128] As a result, the following three test scripts are generated in the case of FIG. 7 .
[0129] —<Home>—<Home>
[0130] —<Home>—<Browse>—<Category>—<Subcategory>—<Item>—<Home>
[0131] —<Home>—<Search>—<SearchResults>—<Item>—<Home>
[0132] (4-2) Merging of Test Scripts Obtained in (4-1): The test scripts obtained in (4-1) are merged together in sequence. When the last screen of the i th test script and the first screen of the i+1 th test script are the same, the latter is omitted. When they are different, transition is made in which the URL of the top screen (in this case, Home) of the application is designated so as to shift to the first screen of the i+1 th test script. As a result, the test scripts are merged into the following one test script:
[0133] <Home>—<Home>—<Browse>—<Category>—<Subcategory>—<Item>—(URL transition)—<Home>—<Search>—<SearchResults>—<Item>—<Home>
[0134] A more detailed algorithm of the path for screen transition will be described in a third embodiment, to be described later.
[0135] (5) Algorithm for Generating Test Script for Comprehensive Execution of Combinations of Form Elements: Of Form elements of HTML, for such elements that a limited number of items are selected from multiple items, their combinations are comprehensively tested.
[0136] For the application of FIG. 7 , there are two kinds of titleOption, two kinds of descriptionOption, and seven kinds of category Selection, Therefore, it is necessary to execute the screen (Search screen) containing Form elements repeatedly for a total sum of 2×2×7=28 times. To execute the repetition with the shortest path, the following algorithm is used:
[0137] 1) Find the smallest of the paths starting from Form screen and returning to Form screen. In the case of FIG. 7 , <Search>—<SearchResults>—<Search> is found. However, the path is not always present generally.
[0138] 2) Find the smallest of the paths that starts from the screen next to Form screen and shifts to the top screen of the application by URL transition into Form screen. Such a path is always present.
[0139] 3) Compare the lengths of the paths of 1) and 2), and repeat execution with a shorter path.
[0140] The optimum method for comprehensively testing the combinations of Form elements will be further described in a fourth embodiment.
[0141] FIG. 9 shows an example of the generated test script. The part denoted by numeral 91 indicates a part obtained by instancing the helper class. In the screen operation by the user, the part indicated by numeral 92 is for selecting a list box; the part indicated by numeral 93 is for setting a text field; the part indicated by numeral 94 is for selecting a radio button; the part indicated by numeral 95 is for clicking a submit button; and the part indicated by numeral 96 is used for comparing the texts.
[0142] FIG. 10 shows the case of searching for “Radio Button” as an example of dynamic search for a GUI object. Search keys are Class, Name, and Value. The Class key is determined as Html.INPUT.radio because this is an instance of Radio Button helper class. The data pool 97 is searched with the first argument of a select method, “categorySelection” as a key to find an implementation name “detailedSearchForm:radio1”. This serves as Name key. The data pool 97 is searched also with the second argument “All” of the select method. However, there is no corresponding entry. Therefore, the specification name, All, is used as Value key. A GUI object is automatically searched for with the three keys, so that “All Categories” button is found from a radio button group 99 .
[0143] Third Embodiment: An algorithm for generating a less redundant test script will be described for the above-described test script.
[0144] The navigation on the screens of a computer application can be expressed as a directed graph starting at one Home node. FIG. 11 schematically shows the directed graph. The screens are expressed as 1, 2 and so on in correspondence with the nodes, while screen transition is described as (1, 4) or the like in correspondence with the edges. The continuous screen transition starting at Home is called a path, which is expressed as (H, 1, 4) or the like. The continuous screen transition without starting at Home is called a sub path, which includes (1, 4, 6).
[0145] From the viewpoint of path coverage in functional testing, (a) it is necessary to find a set of paths that pass all the edges at least one time. In the case of FIG. 11 , the following set A meets the condition.
[0146] Set A={(H, 1, 4, 6), (H, 2, 6, H), (H, 2, 6, 1), (H, 3, 5, 7), (H, 3, 5, 8, 3)}
[0147] However, this set is redundant because edges H→2, 2→6, H→3, 3→5 are passed two times. The number of passages is defined for each edge to show the redundancy. The number of passages indicates how many times each edge is passed by a set of paths. For set A, the number of passages of the four edges is two, while the number of passages of the other edges is 1. Thus, it is desirable to meet the condition (a) and also (b) find a set of paths whose sum total of passages is as small as possible.
[0148] (1) A simple algorithm that meets the condition (a) includes a breadth-first method. This is a method of starting from Home and copying the path every time the edge branches.
[0000]
<Algorithm 1>
Paths = {(H)};
Output = { };
while (Paths are not empty) {
NextPaths = { };
for (all paths in Paths) {
CopyNum = (the number of unpassed edges of edges starting
from the node at the end of Path);
if (CopyNum! = 0) {
copy Path by CopyNum;
add the respective edges to the front ends of the copied paths;
add the paths to NextPaths;
}
else {
add Path to Output
}
}
Paths = NextPaths;
}
Result = Output;
[0149] FIG. 12 shows how Paths and Outputs change at the determination of the conditions of sentence while in the case where this method is applied to FIG. 11 .
[0150] (2) Depth-first Method: The breadth-first method has the disadvantages that the set of paths generated by the method has high redundancy and a large volume of memory is used at a time for generation. A method for reducing them includes a depth-first method in which the edges are passed from Home as much as possible. However, a simple depth-first method causes unpassed edges, thus needing some device. Thus, the following definitions are first made.
[0151] The distance from home node to a node is the number of shortest steps from home node to the node. For example, in FIG. 11 , the distance from Home node to node 4 is 2, The distance from home node to edge is the distance from Home node to the first node of an edge. For example, in FIG. 11 , the distance from Home node to edge (4, 6) is 2.
[0000]
<Algorithm 2>
Edges = {Set of all edges};
Output = { };
while (Edges are not empty) {
Select any Edge A that is nearest to Home from Edges;
Connects another Edge B in Edges to Edge A. Here (the terminal
node of Edge A) = (the first node of Edge B). When a plurality of Edges
B is present, select any one of them. Similarly, continue to connect Edge
C, Edge D, and so on as long as they are present. However, on arrival at
Home, finish the connection. Set the obtained subpath as Subpath;
Eliminate the edges in Subpath from Edges;
Connect the shortest path (any path when a plurality of paths is
present) connecting Home and the first node of Subpath. Set the
obtained path as Path;
}
Add Path to Output
Result = Output;
[0152] FIG. 13 shows how Edges and Output change at the determination of the conditions of the sentence while in the case where this method is applied to FIG. 11 . Since the algorithm has three options, other results may be given.
[0153] (3) Depth-First Connection Method: Although the method of (2) has lower redundancy than that of (1), the results of application to the directed graph in FIG. 11 shows that the part (H, 3, 5) of the paths (H, 3, 5, 7) and (H, 3, 5, 8, 3) is passed two times.
[0154] An algorithm 3 improved in this point is shown in the flowchart of FIG. 14 . Here, “intermediate node” is defined as a node, of the nodes in the path, which is different from Home node and the terminal node.
[0000]
<Algorithm 3>
Input = {Set of paths obtained after application of the depth-first method};
do {
Path = (contained in Input) AND (the terminal node agrees with the
intermediate node on another path PathA contained in Input);
if (Path is present) {
When one or more Paths are present, select any one of them;
Node = (the terminal node of Path);
if (the number of passages of all the edges between Home and Node
of PathA is two or more)
{
Subpath = (part between Node and the terminal node of PathA);
Connect Subpath to Path;
Decrease the number of all the edges between Home and Node of
Path A by one;
Eliminate PathA from Input;
}
}
else {
break;
} while (true)
Result = Input;
[0155] When this method is applied to FIG. 11 , the results {(H, 1, 4, 6, H), (H, 2, 6, 1), (H, 3, 5, 8, 3, 5, 7)} are obtained.
[0156] In summary, the redundancy is defined in a set of paths as the difference the sum total of passages minus the number of edges in a set of paths. FIG. 15 shows the difference in redundancy when the methods are applied to the directed graph of FIG. 11 . For FIG. 11 , the redundancies cannot be improved more.
[0157] As a fourth embodiment, a method for finding a set of paths for executing the shortest screen transition in testing any combination of Form elements will be described. The screens of applications generally have Form elements as shown in FIG. 16 . The screen in FIG. 16 has Form elements as shown in FIG. 17 . Form elements on the screen of FIG. 16 include the list box of Title 121 (two options), the list box of Description 123 (two options), the list box of Document Dated 127 (three options), the list box of Display Results 128 (five options), and the radio buttons of Search in Categories (seven options). Here TextField 122 , 124 , 125 , and 126 are omitted.
[0158] It is preferable that any combination can be tested in view of testing without leakage of Form elements. For this purpose, the screen needs to be repeatedly executed by 420 times=2×2×3×5×7.
[0159] Suppose that the screen is node 5 of FIG. 11 , and shifts to node 8 by pushing of Search . . . button 130 . If is necessary to execute the edge (5, 8) 420 times so as to test all the combinations of Form elements. Although it is the shortest path that returns to node 5 directly after transition to node 8 , it is generally impossible. For example, for Web applications, the URL of node 5 can be assigned to the location field of the browser. However, since the applications have a state therein, an error often occurs. Such forced transition can generally be made only for Home node.
[0160] Accordingly, a reliable method is to shift directly to Home node after transition to node 8 , then passing the path (H, 3, 5). This is called Home transition method. This method does not always provide the shortest path. An algorithm improved in this point (Form-screen transition method) will be described hereinbelow.
[0161] First, the following definitions are made. The form node is a node having Form element, for example, which corresponds to node 5 of FIG. 11 . The form-execution result node is a node to be shifted after execution of Form node, for example, which corresponds to node 8 of FIG. 11 . Symbol “+=” indicates that the path on the right side is connected to the tail end of the path on the left side
[0162] <Algorithm 4>:
[0163] Suppose that Form node is NodeA and Form execution result node is NodeB. Suppose that the path to NodeA is Path A. Let x be the distance between Home node and NodeA, and N be the repeat count of Form node; the shortest distance y from NodeB to NodeA is found by Dijkstra method, and its subpath is called Subpath. When it is impossible to reach NodeA, y is +infinity;
[0000]
if (x+1 > y) {
Path = Path A;
Path += (NodeA, NodeB);
For (int i = 0; i < N−1; i++) {
Path += Subpath;
Path += (NodeA, NodeB);
}
}
else {
Path = null;
for (int i = 0; i < N−1; i++) {
Path += PathA;
Path += (NodeA, NodeB);
Path += (NodeB, Home);
}
Path += PathA;
Path += (NodeA, NodeB);
}
Result = Path;
[0164] FIG. 18 is a flowchart for algorithm 4.
[0165] FIG. 19 shows the execution count of screen transition when Home transition method and Form-screen transition method are applied to the directed graph of FIG. 11 . This shows that Form screen transition method can save the execution count.
[0166] In a fifth embodiment, assume a structure in which a data pool and the entries therein are not present.
[0167] The name of Form element for use in designing and that for implementation are generally different. For example, at designing, a radio button may be named categorySelection, while, at implementation (for the purpose of standardization or the like), it may be named detailedSearchForm:radio1. To map them, the invention can use a data pool. Here, no data pool may be used. In this case, assume that the name used in designing is used also in implementation. The names can be coresident, in other words, one Form element can be mapped from design name to implementation name using a data pool, while another Form element may be held in design name.
[0168] FIG. 20 shows an example of implementation in which coresident configuration is allowed. Access to the data pool is given through a line indicated by numeral 180 . When there is no entry using design name as key, an exception occurs, and design name is used at it is (a line indicated by numeral 181 ).
[0169] (1) Use of Normal Expression in Expected Value: At the execution of functional testing, the measured value on the screen and the expected value are compared. This is performed through comparison of character strings. The amount of the character string to be measured can be enormous. Accordingly, it takes much labor to input an expected value that agrees with it, with possible typing mistake. To cope with the problems, the invention has enabled to use normal expression for the expected value. For example, when normal expression “.*Search for Location.*” is assigned to a measured character string “January 16, 2006, Monday, Search for Location Username Password”, the test can attain success. Here “.*” is a metacharacter indicative of any character larger than or equal to zero.
[0170] FIG. 21 shows an information processing unit 100 as a typical example of the test-script generating apparatus 10 in FIG. 1 . An example of the hardware configuration of the information processing unit 100 will be described. The information processing unit 100 includes a central processing unit (CPU) 1010 , a bus line 1005 , a communication I/F 1040 , a main memory 1050 , a basic input-output system (BIOS) 1060 , a parallel port 1080 , a USB port 1090 , a graphic controller 1020 , a VRAM 1024 , a speech processor 1030 , an I/O controller 1070 , and input means 1100 including a keyboard and a mouse adapter. The I/O controller 1070 can connect to storage means such as a flexible disk (FD) drive 1072 , a hard disk 1074 , an optical disk drive 1076 , and a semiconductor memory 1078 .
[0171] The speech processor 1030 connects to an amplifier circuit 1032 and a speaker 1034 . The graphic controller 1020 connects to a display 1022 .
[0172] The BIOS 1060 stores a boot program executed by the CPU 1010 at the start of the information processing unit 100 and programs depending on the hardware of the information processing unit 100 . The flexible disk drive 1072 reads programs or data from a flexible disk 1071 and provides them to the main memory 1050 or the hard disk 1074 via the I/O controller 1070 .
[0173] Examples of the optical disk drive 1076 include a DVD-ROM drive, a CD-ROM drive, a DVD-RAM drive, and a CD-RAM drive. In this case, an optical disk 1077 corresponding to each drive has to be used. It is also possible that programs or data are read from the optical disk 1077 with the optical disk drive 1076 , and are provided to the main memory 1050 or the hard disk 1074 via the I/O controller 1070 .
[0174] Computer programs are provided to the information processing unit 100 by the user through a recording medium such as the flexible disk 1071 , the optical disk 1077 , or a memory card. The computer programs are read from the recording medium via the I/O controller 1070 , or downloaded via the communication I/F 1040 and installed in the information processing unit 100 for execution. The operation that the computer programs works on the information processing unit is omitted here because it is the same as that of the test-script generating apparatus 10 described with reference to FIGS. 1 to 20 .
[0175] The computer programs may be stored in an external storage medium. Examples of the storage medium are, in addition to the flexible disk 1071 , the optical disk 1077 , and the memory card, magneto-optical recording media such as an MD and tape media. Furthermore, a storage unit such as a hard disk or an optical disk library in a server system connected to a dedicated communication line or the Internet can be used as a storage medium, from which computer programs may be sent to the information processing unit 100 via the communication line.
[0176] Although the invention has been described with the information processing unit 100 , the same functions as those of the information processing unit can be achieved in such a manner that programs having the functions are installed in a computer, and the computer is operated as an information processing unit. Accordingly, the information processing unit described as an embodiment of the invention can also be achieved by the above-described methods and computer programs therefor.
[0177] The apparatus of the invention can be achieved by hardware, software, or a combination of hardware and software. A typical example of execution by the combination of hardware and software is by a computer system having a predetermined program. In such a case, the predetermined program makes the computer system execute the process according to the invention in such a manner that it is loaded on the computer system and executed. The program includes an instruction group that can be expressed by any language, code, or notation. Such an instruction group enables the system to execute predetermined functions directly or after one or both of (1) conversion to another language, code, or notation and (2) duplication in another medium have been made. Of course, the scope of the invention includes not only the program itself but also a program product including a medium in which the program is stored. Programs for executing the functions of the invention can be stored in any computer readable medium such as a flexible disk, an MO, a CD-ROM, a DVD, a hard disk, a ROM, an MRAM, or a RAM. The programs can be downloaded from another computer system connected via a communication line or can be copied from another medium so as to be stored in a computer readable medium. Such programs may also be compressed or divided into two or more and stored in one or more recording media.
[0178] Although the invention has been described in its preferred embodiments, the technical scope of the invention is not limited to that of the embodiments. It is to be understood by those skilled in the art that the embodiments can be variously changed and modified. Accordingly, it should also be understood from the description of the claims that various changes and modifications are included in the technical scope of the invention.
REFERENCE NUMERALS
[0179] 1 : specification file
[0180] 2 : input/output variable extracting section
[0181] 3 : screen-transition extracting section
[0182] 4 : input/output variable
[0183] 5 : input/output variable type
[0184] 6 : screen-transition information
[0185] 7 : test-script generating section
[0186] 8 : test-script file
[0187] 10 : test-script generating apparatus
[0188] 11 : runtime library
[0189] 12 : application under test
[0190] 13 : automated-testing execution tool
[0191] 20 : formal specification
[0192] 21 : declaring section
[0193] 22 : axiom section
[0194] 23 : schema
[0195] 24 : schema composition
[0196] 31 : input variable book
[0197] 32 : output variable abstract
[0198] 33 : property file
[0199] 34 : functional test script
[0200] 35 : data pool
[0201] 51 : Z language editor
[0202] 52 : JFace text editor framework
[0203] 53 : Eslipse runtime
[0204] 54 : RFT
[0205] 55 : test script
[0206] 56 : class library
[0207] 57 : RFT data pool
[0208] 60 : UML-specification analyzing section
[0209] 61 : UML2.0 editor
[0210] 62 : transformation API
[0211] 63 : test-script generator plug-in
[0212] 64 : RFT6.1.1
[0213] 66 : activity diagram
[0214] 67 : test script
[0215] 68 : helper Java class
[0216] 69 : RFT data pool
[0217] 70 : Home screen
[0218] 71 : All Screen
[0219] 72 : Search screen
[0220] 73 : SearchResults
[0221] 74 : Browse screen
[0222] 75 : Category screen
[0223] 76 : Subcategory screen
[0224] 77 : Item screen
[0225] 78 : CategorySelection
[0226] 79 : title
[0227] 80 : description
[0228] 81 : browse
[0229] 82 : category
[0230] 91 : helper class instance
[0231] 92 : list box selection
[0232] 93 : text field setting
[0233] 94 : radio button selection
[0234] 95 : submit button click
[0235] 96 : text comparison
[0236] 97 : data pool
[0237] 98 : table
[0238] 99 : radio button group
[0239] 100 : information processing unit | A method for eliminating ambiguity and incorrectness of the specification determined in a requirement defining phase in developing an information system, and systematically verifying whether an automatically executed test scenario agrees with the original requirements in a functional testing phase, includes extracting an input variable, an output variable, and the respective types of the variables from a specification file in screens; extracting screen-transition information from a composite functional specification containing specifications in screens; and executing the following processes from the top for each screen that appears in screen transition. For the input variable, the apparatus generates a test script indicative of an action (clicking or a character set) corresponding to an object associated with the input variable. For the output variable, the apparatus generates a test script for comparing text information displayed on a screen with an expected value determined from the output variable. | 6 |
[0001] This application claims under 35 U.S.C. 119, the right of priority and the benefit of earlier filing date of provisional application Ser. No. 60/894,463, filed Apr. 5, 2006 and incorporated herein by reference. Both this application and the provisional application have common inventors.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a novel and very useful cane/walking aid adapted to provide safety, convenience, and peace of mind for the user. More particularly, the cane/walking aid is designed to contain a flashlight, a high-decibel alarm, door-jamming device, mace, GPS, flashing red light, space for medical alert information storage, and other useful mobile technologies to afford safety and a feeling of security for the owner.
[0003] The American populace is aging. In the 2000 census, of the 281,421,906 population, 34,991,753 individuals were 65 and older or 12.4 percent of the population. High percentages of the aging population will become physically disabled and will need a cane/walking aid to compensate for leg, knee, foot, and hip impairment. According to the U.S. National Health Interview Survey, an estimated 7.4 million people use such devices for mobility limitations; 4.6 million for orthopedic impairments (including missing limbs); U.S. Government statistics state that the older population is growing and is expected to double by 2050 and the oldest old (those 85 and older) has grown nearly three times as fast as the overall population.
[0004] The safety cane has several functions. While the owner sleeps, the cane/walking aid can be placed under any doorknob either of two ways to secure the door as a door-jamming device. Later, when the owner leaves the residence the cane/walking aid will provide balance and mobility support. If the user becomes unconscious or unable to speak, life-saving medical alert information (identification, illnesses and medications) will be readily available inside the cane/walking aid for those trying to help. The safety alarm will sound if the user pulls the alarm string, which is to be wrapped around the user's wrist. This high-decibel alarm will also sound if the user becomes separated from the cane/walking aid. When it becomes dark, the cane/walking aid user will have the peace of mind of being visible when the flashing safety light is activated. Also, the built in flashlight will light the user's way. If the user is bothered by a dog or unwanted person the user will have mace, the alarm, and/or other personal self-defense devices at their disposal. A G.P.S. device can also be contained inside the cane/walking aid to help locate the user if lost. The cane/walking aid can accommodate a talking G.P.S. to be used to navigate with which would be very useful for the visually impaired. Also the cane/walking aid can accommodate an electronic insect repellent device.
[0005] No known cane/walking aid currently provides all of these safety/security functions. Most canes simply provide walking support and a few provide light. The need for mobility and independence is a basic human need and presents itself in many settings of weather, daylight and darkness. This new novel cane/walking aid truly supports full mobily and security to those who need it.
[0006] Henceforth, a safety cane would fulfill a long felt need in the aging and disability population. This new invention utilizes and combines known and new technologies in a unique and novel configuration to overcome the aforementioned problems and fulfill the need for increased mobility, independence, safety, and a sense of security.
SUMMARY OF THE INVENTION
[0007] The general purpose of the present invention, which will be described subsequently in greater detail, is to provide increased security, peace of mind and independence, while also providing mobility support. The cane/walking aid has many of the advantages mentioned heretofore and many novel features that result in a new cane/walking aid which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art, either alone or in any combination thereof.
[0008] In accordance with the invention, an object of the present invention is to provide an improved mobility experience capable of offering personal safety/self defense through the mechanisms of a high-decibel alarm, mace, flashlight, and flashing/reflector red light.
[0009] It is another object of this invention to provide an improved cane/walking aid that can also be used for home security as a duo style, door-jamming device capable of meeting or exceeding the usual and expected functions of a typical cane/walking aid.
[0010] It is a further object of this invention to provide critical safety information in the form of medical alert ID, medications and illnesses of the user.
[0011] It is still a further object of this invention to provide for a GPS device for locating a user who is lost and/or assist the user with improved navigation.
[0012] It is also a further object of this invention to provide a electronic insect repellent specifically to repel mosquitoes.
[0013] It is yet a further object of this invention to provide a an improved mobility experience by providing increased safety and security devices incorporated into the cane/walking aid, which will in turn provide an increased sense of security, peace of mind and independence, particularly for some of the most vulnerable: the aging and disabled populations.
[0014] 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, together with further advantages and objects thereof, may best be understood by reference to the following description taken in connection with accompanying drawings wherein like reference characters refer to like elements. Other objects, features and aspects of the present invention are discussed in greater detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a perspective view of the safety cane;
[0016] FIG. 2 is a side view of the safety cane;
[0017] FIG. 3 is an top view of the safety cane;
[0018] FIG. 4 is a front end view of the safety cane;
[0019] FIG. 5 is a cross sectional view of the concave connector; and
[0020] FIG. 6 is a cross sectional side view of the safety cane.
DETAILED DESCRIPTION
[0021] The above description will enable any person skilled in the art to make and use this invention. It also sets forth the best modes for carrying out this invention. There are numerous variations and modifications thereof that will also remain readily apparent to others skilled in the art, now that the general principles of the present invention have been disclosed.
[0022] There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
[0023] In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of descriptions and should not be regarded as limiting.
[0024] Looking at FIG. 1 it can be seen that the safety cane 2 has a hollow, perforated head 4 with a plethora of orifices 5 therethrough and a concave saddle 7 formed on it's topmost surface. A first, removable, flexible, resilient sealing cap 8 frictionally engages the outer surface at the proximate end of the head 4 , and a second, flexible resilient, removable sealing cap 9 frictionally engages the outer surface at the distal end of the head 4 . An extendable shaft 6 extends normally from the head 4 , centered at the approximate longitudinal midpoint of the head 4 . The bottom end of the shaft has a flexible, gripable tip 10 frictionally engaged over the outer surface of the bottom end.
[0025] The shaft 6 has a inner, lower member 12 that fits inside the outer middle member 14 . Both members have a linear series of equally spaced penetrations 17 formed through their hollow tubular bodies that when aligned, allow for the insertion of a first spring button 20 through the aligned penetrations 17 of both the members so as to lock the shaft lower member 12 and middle member 14 in a desired length. Such spring buttons that reside inside multi piece hollow tubular body assemblies of linearly extendable members are well known in the art.
[0026] Looking at FIGS. 2 and 6 it can be seen that at the top end of the shaft 6 , an upper member 16 having a semi-cylindrical, angled contour 22 cut into its uppermost end, is affixed normally to the head 4 by the insertion of the head stub shaft 24 into the internal recess 26 of the upper member 16 . The uppermost point of the angled contour 22 extends to the approximate linear midpoint of the head 4 , thereby allowing for the removal of the extendable shaft 6 . A second spring button 28 extends normally from the stub shaft 34 and locks the stub shaft 24 to the upper member 16 through penetration 17 in a similar fashion to the locking of the shaft lower member 12 and middle member 14 to a desired length as discussed above.
[0027] In a door jamming operation, the concave saddle 7 of the head 4 of the safety cane 2 may be abutted adjacent to the bottom side of a conventional door knob and the shaft 6 extended such that the tip 10 reaches the floor while the linear axis of the shaft resides at an acute angle with the linear axis of the door. Where non conventional door handles are used, the head 4 may be removed from the shaft 6 by depressing the second spring button 28 and extracting the stub shaft 24 , thereby exposing the angled contour 22 of the upper member 16 , which may be jammed under the door handle with the shaft 6 adjusted and placed substantially similar to that discussed above. The upper member's angled contour 22 is approximately 1½″ in length and approximately 2¼″ wide between the two prongs. This has been found suitable to accommodate a wide variety of door handles.
[0028] The head 4 internally houses several safety and convenience related articles. These are best explained by viewing FIGS. 3 , 4 , and 6 collectively. The interior of the head 4 houses a colored reflector 30 , frictionally constrained by the second cap 9 at the distal end; a mace (or equivalent) spray canister 32 and a flashlight 34 constrained at the first cap 8 at the proximate end such that the mace cannister spray tip 36 and release button 40 as well as the flashlight switch 38 and flashlight 34 extend partially therethrough the first cap 8 ; a portable GPS device 42 ; an audible alarm device 44 and a electronic insect repeller 46 such that the alarm enabling mechanism 48 extends through one of the perforations 5 in the head 4 .
[0029] With this configuration there is ample room remaining in the head 4 for the storage of medicine, documents, MP3 devices, knives, alert bracelets, whistles, pens, sunglasses, lotion, contacts and a plethora of other owner selected safety and convenience articles.
[0030] The cane may be illuminated at night, used to send audible distress signals, used to defend oneself via pepper or mace spray, used to reflect approaching cars light back, used to deter insects, used to navigate via audible GPS signals and of course to steady the walker. Other items may be added to the cane handle tube that will enhance the personal safety of the user because of the advancement of micro-technology, which is likely to allow for increasingly smaller safety devices to be used within the head 4 . This coupled with the duo door jamming capabilities make this an indispensable aid for all.
[0031] The materials of the safety cane's construction will be lightweight yet strong and will encompass, aluminum, metal, and polymers. The head 4 is approximately two inches in diameter and six inches long. The first cap 8 and second cap 9 are approximately 2¼″×1⅜″ and made of an appropriate material such as rubber, metal, or plastic, etc. The head 4 may be transparent, or opaque having a viewing window. The concave saddle 7 is approximately 2″ long×1¼″ wide and may also have a soft rubber or rubber-like gripping surface. This beveled or recessed section is designed to grip under a doorknob to effectuate the door jamming function of the safety cane 2 . When using the safety cane as a walking aid, the user can also rest his/her hand in this recessed area.
[0032] Since the safety cane head 4 is removable this allows for user flexibility with the arrangement of the numerous components to be placed inside. Removing the head 4 will also allow the user to utilize the cane 2 itself as a door jammer and to be able to use the internal components separately.
[0033] Note, that while the alarm enabling mechanism 48 is depicted as a button it is known that such devices commonly use a string attached to a releasable alarm pin. In such cases, the string may be secured around the walker's wrist, while walking with the safety cane 2 . This allows the user to easily activate the alarm 44 if necessary. If the user loops the string snugly around the wrist (recommended), the alarm can be activated if the user falls or is in some way separated from the cane 2 .
[0034] The GPS device 42 may be used to locate the user of the safety cane 2 if they become lost. This is especially useful for elderly or mentally disabled safety cane users who may become disoriented. Another optional GPS device would allow the user to hear verbal directions as they navigate with the safety cane.
[0035] A blank card such as a business card or smaller will be provided to the user for medical alert information such as illnesses or medications and identifying information. The card can easily be placed inside the head 4 and can be viewed through a transparent head 4 by anyone who is trying to assist the user of the safety cane 2 .
[0036] All components located within said cane head 4 may be physically secured in place through the use of simple mechanical stops. Since these will vary with the user's choice of components these stops are simple polymer tabs that may be glued to the inner surface of the hollow cane head 4 . These are well known in the art and of numerous configurations, and as such have not been illustrated, although the commonest form would be a “T” formed from the normal intersection of a curved plate and a planar plate.
[0037] As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. Any dimensions disclosed herein are not meant to be limiting but merely to demonstrate the preferred embodiment dimensions.
[0038] Although shown as a round tubular design, it can be of square, rectangular, oval or other geometric configuration. The material of construction may be a polymer, steel or metal and may be varied as required by the desired resilience and weight. | The present invention is a Cane/walking aid that provides the user with many security features along with mobility support. The cane/walking aid can be placed under the doorknob to secure the door(s) as a door-jamming device. The cane/walking aid will provide balance and mobility support. Life-saving medical alert information (identification, illnesses and medications) will be readily available inside the cane/walking aid. A safety alarm will sound if the user pulls the alarm string, which is to be wrapped around the user's wrist. This high-decibel alarm will also sound if the user becomes separated from the cane/walking aid. It also has a flashing safety light and a built in flashlight. The cane will have mace, an alarm, and/or other personal self-defense devices within. A G.P.S. device or a talking G.P.S. is provided for navigation. The cane/walking aid can accommodate an electronic insect repellent device. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to a method and apparatus for processing a substrate by use of plasma, and particularly to a technique that is suitable for a microwave plasma CVD apparatus for forming a thin film on a substrate to enhance performance in terms of operational efficiency and ease of maintenance.
A conventional microwave plasma processing apparatus is designed to clean up its interior, after a plasma-based process such as thin film formation, by application of a high-frequency electric field to the internal wall of the vacuum chamber in which the substrate has been processed so that deposits on the wall surface are etched off, as described in Japanese patent publications JP-A-1-231320, JP-A-1-231321, JP-A-1-231322, and JP-A-1-231323.
However, the above-mentioned conventional method is solely intended to clean up the vacuum chamber internal wall through application of the high-frequency electric field, and it does not consider the cleaning of places around the substrate holder where cleaning is most imperative. Moreover, the frequency of the applied electric field is not optimized and therefore the cleaning effect is not satisfactory. Another problem is that the cleaning operation promotes the sputtering of the internal wall surface, thereby spreading metallic contamination. A further problem is that for safety purposes, an expensive insulation structure is required for the chamber wall that functions as an electrode.
SUMMARY OF THE INVENTION
An object of this invention is to provide a microwave plasma processing method and apparatus capable of cleaning up places around the substrate holder sufficiently.
Another object of this invention is to provide a microwave plasma processing method and apparatus capable of preventing metallic contamination from the chamber internal wall from spreading due to sputtering.
Still another object of this invention is to provide a microwave plasma processing method and apparatus capable of economically achieving a prescribed degree of insulation.
The above objectives are accomplished in the following manner:
(1) A high-frequency electric field applied during the cleaning process is of such a frequency that the cleaning gas ions can follow changes in the electric field.
(2) A high-frequency electric field is mainly applied to the substrate holder.
(3) The electric field application electrode that is activated in the cleaning process is shaped such that normals of the electrode surface reach the portions of the internal wall surface of the vacuum chamber where cleaning is needed.
(4) When multiple electrodes (one of which may be the substrate holder) are used, each electrode is controlled independently.
The plasma-based cleaning process for the internal wall surface of the vacuum chamber is performed by ions and radicals in the plasma. Radicals move in accordance with the diffusion equation, whereas ions move in response to an electric field. In removing deposits on the wall surface by etching, the etching characteristics differ depending on the material of the deposits. Generally, ions in addition to radicals reaching the deposits provide impingement energy which is added to etching energy, resulting in a faster etching process. Particularly, insulating materials such as SiO 2 and SiN are etched not only by the impingement energy of the ions, but through direct reaction with the ions. Accordingly, it is crucial for an effective cleaning process to let ions reach places where deposits exist.
When a changing electric field acts on ions in a plasma, the ions move in response to the changes in the electric field. When the frequency of the electric field is raised to a certain value (e.g. above 1 MHz), the ions can no longer follow the changes in the electric field and thus become quiescent in a high-frequency electric field. Generally, ions are said to be capable of following a changing electric field when the ions move 1 mm or more in the electric field. The limit of frequency which ions can follow differs depending on the weight of the ions, and it is 1 MHz or lower in the case of fluorine ions, for example. Electrons weigh less than ions, and they can follow an electric field of a high frequency which ions cannot follow. Accordingly, only electrons reach an electrode to which a high-frequency electric field is applied, and the electrode has a negative induced d.c. potential with respect to the plasma.
Ions impinge on the electrode as a result of being attracted to the electrode by the induced d.c. potential. As a result, when an electric field of a high frequency which ions cannot follow is applied for cleaning, a cleaning process performed by the ions attracted by the d.c. takes place at the places where the high-frequency electric field is applied, while the ion-based cleaning process scarcely takes place in places where the high-frequency electric field is not applied.
When a high-frequency electric field which ions can follow is applied to the electrode, ions in the plasma reciprocate in a direction parallel to normals of the electrode surface in response to the high-frequency electric field applied to the electrode. Accordingly, ions reach not only the electrode surface, but also object surfaces located in the direction of the normals of the electrode surface, such that a cleaning process takes place for these object surfaces.
Since the ion impingement speed and the quantity of impinging ions are greater in places where the electric field is applied, the electric field is preferably applied to places where large deposits exist. A plasma processing apparatus for processing a substrate inherently produces large deposits on the substrate and substrate holder. Due to this, it is crucial for the effective cleaning of the substrate holder and the internal wall surface of the vacuum chamber to apply a high-frequency electric field which ions can follow to an electrode that is disposed on the substrate holder. If the electrode is disposed on the internal wall of the vacuum chamber, a large part of the deposits on the substrate holder are left unremoved even though the electrode is cleaned completely. Continuing the cleaning process after the electrode on the internal wall has been cleaned completely in an attempt to clean the substrate holder will produce etching and ion sputtering of the electrode on the internal wall, creating another contaminant.
When a cleaning electrode is disposed on the substrate holder, it is desirably installed such that normals of the electrode surface intersect with virtually the entire internal wall surface of the vacuum chamber, since ions reciprocate in a direction parallel to the normals of the electrode surface, and the interior of the vacuum chamber will be cleaned more evenly and effectively.
When more than one cleaning electrode is used, more effective cleaning can be achieved to match the quantity of deposits on the surfaces that confront the electrodes and the surfaces in the direction of the normals. The cleaning effect can be further improved by independently controlling the power and application time of a high-frequency electric field applied to each electrode.
For an apparatus based on electron cyclotron resonance (ECR), highly active plasma seeds, i.e., having a high cleaning effect, are created within an ECR region, and therefore positioning the ECR region in contact with or close to places where deposits are abundant or cleaning is difficult will achieve a more effective result.
An excessive cleaning process can be prevented through the provision of an interior inspection means that is operated during the cleaning process.
According to this invention, a vacuum chamber which has finished a plasma-based processing can be cleaned up in a short time, and consequently the conventional cleaning process that compels the apparatus to be open to the atmosphere is required less frequently, whereby the quality and throughput of products can be improved owing to the reduction of contaminants that are created in the film forming process. The inventive method and apparatus are capable of achieving a uniform cleaning speed for surfaces at various positions within the vacuum chamber, whereby the wear of component parts inside the apparatus due to the cleaning process can be prevented.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional diagram showing the principal portions of a microwave plasma processing apparatus based on the second embodiment of this invention;
FIG. 2 is a cross-sectional diagram showing the principal portions of the apparatus based on the first embodiment of this invention;
FIG. 3 is a graph resulting from the first embodiment of this invention, showing the amount of deposit at various positions in the apparatus after the formation of a SiO 2 film;
FIG. 4 is a graph resulting from the first embodiment of this invention, showing the amount of deposit remaining after a cleaning process at various positions in the apparatus;
FIG. 5 is a graph resulting from the first embodiment of this invention, showing the ratio of the amount of etching and the amount of deposit at various positions in the apparatus for the formation of a SiO 2 film followed by a cleaning process;
FIG. 6 is a graph resulting from the second embodiment of this invention, showing the ratio of the amount of etching and the amount of deposit at various positions in the apparatus for the formation of a SiO 2 film followed by a cleaning process;
FIG. 7 is a cross-sectional diagram showing the principal portions of the conventional microwave plasma processing apparatus;
FIG. 8 is a graph resulting from the apparatus shown in FIG. 7, showing the ratio of the amount of etching to the amount of deposit at various positions in the apparatus for the formation of a SiO 2 film followed by a cleaning process;
FIG. 9 is a cross-sectional diagram showing the principal portions of the apparatus based on the fourth embodiment of this invention;
FIG. 10 is a graph resulting from the fourth embodiment of this invention, showing the ratio of the amount of etching to the amount of deposit at various positions in the apparatus for the formation of a SiO 2 film followed by a cleaning process;
FIG. 11 is a cross-sectional diagram showing the principal portions of the apparatus based on the fifth embodiment of this invention;
FIG. 12 is a cross-sectional diagram showing the principal portions of the apparatus based on the seventh and eighth embodiments of this invention;
FIG. 13 is a graph resulting from the seventh embodiment of this invention, showing the ratio of the amount of etching to the amount of deposit at various positions in the apparatus for the formation of a SiO 2 film followed by a cleaning process;
FIG. 14 is a graph resulting from the eighth embodiment of this invention, showing the trend in time of the m/e value of O 2 particles during the cleaning process; and
FIG. 15 is a cross-sectional diagram showing the principal portions of the apparatus based on the tenth embodiment of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of this invention will be explained with reference to the drawings.
Embodiment 1
FIG. 2 shows the cross section of the principal portions of the microwave plasma processing apparatus based on the first embodiment of this invention. The apparatus comprises a vacuum chamber 5 having a window 4 which transmits a microwave 3, a cylindrical substrate holder 2 disposed at the bottom of the vacuum chamber beneath the window 4, reactive gas conduits 6 and 7 for feeding substrate processing gases into the vacuum chamber, a cleaning gas conduit 8 for feeding a cleaning gas into the vacuum chamber, a gas evacuation port 9 formed in the wall of the vacuum chamber, an electromagnetic winding 10 disposed near the window 4 outside the vacuum chamber 5 for producing a magnetic field in the vacuum chamber, and a high-frequency power source 12 connected to the substrate holder 2.
The substrate holder 2 is designed to mount a substrate of 125-mm diameter, and a substrate 1 to be processed is mounted on the surface of the substrate holder 2 that confronts the window 4. The remaining surfaces of the substrate holder 2 are covered with a quartz insulation cover 11, which is enclosed on the cylindrical side surface of the substrate holder 2 by a cylindrical grounding electrode 14 made of stainless steel. The substrate holder is connected to the high-frequency power source 12 and the electrode 14 is grounded, and a high-frequency electric field is applied effectively to the substrate mounting surface.
This apparatus was used to form a SiO 2 film on the substrate 1 by feeding SiH 4 gas at 20 ml/min and O 2 gas at 200 ml/min into the vacuum chamber 5 through the reactive gas conduits 6 and 7, evacuating the vacuum chamber to 0.3 Pa, applying a magnetic flux at a flux density of 875 gauss or more produced by the electromagnetic winding in a direction substantially normal to the substrate, and applying a microwave of 600 W. After microwave application for five minutes, a SiO 2 film with a thickness of 1 μm was formed on the substrate. FIG. 3 shows the amount of SiO 2 deposit at positions indicated by (1) through (8) in FIG. 2.
After the substrate 1 with the SiO 2 film being formed thereon was taken out, the vacuum chamber was cleaned (etched) by feeding C 2 F 6 gas through the cleaning gas conduit 8 in place of the reactive gases previously fed through reactive gas conduits 7 and 8, and applying the same microwave for five minutes to generate plasma. Besides the C 2 F 6 gas, other useful cleaning gases include halogenide gases of CF 4 , CHF 3 , SF 6 , F 2 , HF, Cl 2 and HCl. FIG. 4 shows the amount of SiO 2 deposit at the positions (1) through (8) in FIG. 2 after cleaning.
It is crucial for the cleaning process to remove a deposit on the inner surfaces of the vacuum chamber evenly in a short time. However, the amount of deposit and the amount of etching at each position are different, and it is difficult to assess the uniformity of cleaning among the measuring positions through comparison of the graphs of FIGS. 3 and 4.
For the easy assessment of the uniformity and speed of cleaning among the positions, FIG. 5 shows the ratio of the amount of etching to the amount of deposit at the measuring positions. On the graph, the solid line A is derived from the measurement results of FIGS. 3 and 4. FIG. 5 reveals that cleaning the deposit by merely replacing the reactive or film forming gases with the cleaning gas takes about three times as long as forming the film, and the cleaning efficiency is particularly low at the positions (6) and (7), i.e., the side wall of the substrate holder and the wall of the vacuum chamber confronting the side wall of the substrate holder.
Next, a high-frequency electric field of 13.56 MHz and 100 W produced by the high-frequency power source 12 was applied to the substrate holder 2 during the cleaning process. The result of this cleaning process is shown by the dashed line B in FIG. 5. The graph reveals that the cleaning speed is improved only at the position (1) which is part of the substrate holder 2 where the electric field was applied, and there is no effect at the other positions.
Next, the high-frequency power source was replaced and a high-frequency electric field of 400 kHz and 100 W was applied to the substrate holder 2 during the cleaning process. The result of the cleaning process is indicated by C in FIG. 5. The electric field of 400 kHz allows fluorine ions in the plasma to move in response to the changes in the electric field, and the ions can move along the electric lines of force within the reach of the electric field around the portion to which the electric field is applied. The result of measurement reveals that the cleaning speed was improved by about two times for the surface of the substrate holder 2 on which the substrate 1 is mounted and the confronting surface where the electric field is strong.
It can be concluded from the above examination that for the plasma-based cleaning process, the application of an electric field of a frequency which allows ions in the plasma which contribute to the cleaning to follow the changes in the electric field to the interior of vacuum chamber contributes significantly to the improvement of the cleaning speed.
Embodiment 2
FIG. 1 shows the cross section of the principal portions of the microwave plasma processing apparatus based on the second embodiment of this invention. This apparatus is derived from the one shown in FIG. 2, with only the grounding electrode 14 thereof being replaced with a cylindrical electric field application electrode 13 made of stainless steel.
Experiments with a cleaning process following the formation of a SiO 2 film under the same conditions as in the first embodiment were conducted. This time, the high-frequency electric field of 13.56 MHz/400 kHz and 100 W which was applied to the substrate holder in the first embodiment was applied to the cylindrical electrode 13. FIG. 6 shows the ratio of the amount of etching to the amount of deposit after the cleaning process at the measuring positions. On the graph, indicated by the dashed line B' is the result from the electric field of 13.56 MHz, and indicated by the solid line D is the result from the electric field of 400 kHz. The result of the cleaning process without the electric field application is also shown by the solid line A for reference.
FIG. 6 reveals that the cleaning effect is improved only for the surface to which the electric field is applied when the 13.56-MHz electric field which does not allow fluorine ions to follow the changes in the electric field was used, whereas the effect of electric field application extends beyond the surface to which the electric field is applied when the 400-kHz electric field which allows fluorine ions to follow the changes in the electric field is used. In addition, the high-frequency electric field is distributed more widely in the vacuum chamber as compared with the first embodiment, i.e., the high-frequency electric field existed virtually in only the top portion of the vacuum chamber in the first embodiment, whereas in this embodiment it existed effectively in most portions except at the surfaces above the substrate (positions (2) and (3)), resulting in an improved uniformity of cleaning.
It can be concluded from the above examination that the application of an electric field of a frequency which allows the ions to follow changes in the electric field to the substrate holder contributes to the improvement of the uniformity of cleaning as well as the speed of the cleaning process.
Embodiment 3
FIG. 7 shows the cross section of the principal portions of a conventional microwave plasma processing apparatus (the gas conduits, evacuation port and electromagnetic winding are not shown in the figure). In this apparatus, an electric field application electrode 15 made of stainless steel is disposed on the internal wall of the vacuum chamber. Remaining portions are identical to those of FIG. 1.
Experiments with a cleaning process following the film formation under the same conditions as in the first and second embodiments were conducted. FIG. 8 shows the result of the cleaning process. On the graph, the solid line E indicates the result with the application of a 400-kHz electric field, the dashed line B' indicates the result with the application of a 13.56-MHz electric field, and the solid line A indicates the result without the electric field application. The graph of FIG. 8 reveals that when the 13.56-MHz electric field is used, the cleaning effect is improved only for part of the chamber internal wall where the electric field is applied, as in the second embodiment, and with the 400-kHz electric field being applied, the result is not much different from the second embodiment where the electric field is applied to the side of the substrate holder, although the cleaning effect is generally improved on wider surfaces.
Table 1 lists the number of contaminant particles having diameters of 0.3, 0.5 and 1.0 μm and the Fe count value on Si substrates of 125-mm diameter placed in the vacuum chamber after it has been cleaned based on the conventional apparatus of FIG. 7 and the inventive apparatus shown in FIG. 1 and then taken out of the chamber after one minute.
TABLE 1______________________________________ Number of contaminant particlesNo. Item 0.3 μm 0.5 μm 1.0 μm Fe count______________________________________a After 32 5 1 0depositionb RF*0W 24 0 0 0c RF*100w 23 0 0 3d RF*300w 45 9 3 20e HF**100w 7 0 0 5f HF**300w 3 0 0 6g HF**100w 5 0 0 0h HF**300w 1 0 0 0______________________________________ *: 13.56 MHz, **: 400 kHz
In the table, row a is a set of measured values following the SiO 2 film formation. Rows b, c and d are sets of measured values following the cleaning process based on the conventional apparatus of FIG. 7 with the application of 13.56-MHz electric fields of 0, 100 and 300 W, respectively. Rows e and f are sets of measured values following the cleaning process based on the conventional apparatus of FIG. 7 with the application of 400-kHz electric fields of 100 W and 300 W, respectively. Rows g and h are sets of measured values following the cleaning process based on the inventive apparatus shown in FIG. 1 with the application of 400-kHz electric fields of 100 W and 300 W, respectively.
The etching speed is substantially a linear function of the applied power. For example, etching with the application of a 300-W electric field is sped up by three times the degree of speed-up achieved by etching with the application of a 100-W electric field relative to the case of etching without application of an electric field.
In the case of row d of Table 1, the stainless steel electrode on the internal wall of the vacuum chamber is exposed to the cleaning plasma, and in the cases of rows f and h, the stainless steel electrode disposed on the side wall of the substrate holder or on the internal wall of the vacuum chamber is exposed to the cleaning plasma.
Table 1 reveals that the application of a 13.56-MHz electric field is effective for cleaning before the electrode is exposed to the plasma, but the number of contaminant particles and the Fe count increase, i.e., the contamination of the chamber increases due to the sputtering of the electrode, once the electrode is exposed to the plasma (the case of d). In the case of the 400-kHz electric field application, the contamination is not aggravated by the exposure of the electrode (the cases of f and h). However, when the electric field is applied to the electrode on the side wall of the substrate holder (the cases of g and h), the Fe count value cannot be determined. Namely, Fe is detected when the electric field is applied to the electrode on the internal wall of the chamber (the cases of e and f), although the contamination due to sputtering was not observed. Accordingly, contamination caused by sputtering arises in the cases of e and f. There is conceptually no big difference between the amount of electrode sputtering in the cases of f and h, and whether or not contamination arises is presumably dependent on the location of the electrode. When the electrode is located on the side wall of the substrate holder, the position at which the substrate is mounted is virtually in a blind spot with respect to the electrode surface, and it receives little spray from sputtering of the electrode.
It can be concluded from the above examination that when an electric field is used for cleaning, the cleaning process is made more effective by the selection of a frequency that allows ions to follow the changes in the electric field and the selection of an electrode position such that the electric field is formed in a direction extending away from the substrate holder, rather than toward the substrate holder.
Embodiment 4
FIG. 9 shows the cross section of the principal portions of the microwave plasma processing apparatus based on the fourth embodiment of this invention (the gas conduits, evacuation port and electromagnetic winding are not shown in the figure). This apparatus is derived from the one shown in FIG. 1, with the electric field application electrode thereof being reformed so as to change the directivity of the application of the electric field. The substrate holder 2 has its side wall shaped in a continuously curved surface extending from the top of the substrate holder to the bottom of the vacuum chamber, with an electric field application electrode 13' of the same formation being attached on the external surface of the side wall.
Because of the shape of electrode 13', the range of intersection of normals 16 of the electrode surface with the internal wall of the vacuum chamber increases to cover virtually the entire internal wall surface. Experiments with a cleaning process were conducted for this apparatus, and FIG. 10 shows the result. Even without the electric field application as indicated by A', the amount of etching at the measuring position (7) differs from the case of the first embodiment as a result of the different shape of the substrate holder. On the graph of FIG. 10, indicated by A' is the result of the cleaning process without the electric field application, and indicated by E is the result with the application of an electric field of 400 kHz and 100 W to only the electrode 13'. Assuming normals in each unit area of the electrode surface, the number of intersections of the normals with a unit area of the cleaning surface is averaged among different places, and consequently the cleaning effect is also made uniform over the entire surface.
Indicated by E' is the result of the cleaning process with the application of a 400-kHz 300-W electric field. The graph reveals an improved cleaning effect resulting from the increased power. However, the ratio of the amount of etching to the amount of deposit is slightly smaller for the surface of window 4 which confronts the surface of the substrate holder on which the substrate is mounted, i.e., cleaning is not uniform. For the achievement of uniform cleaning, another high-frequency power source 12' was connected to the substrate holder 2 and the cleaning process was conducted with the application of an electric field of 400 kHz and 300 W to the electrode 13' and the application of an electric field of 400 kHz and 50 W to the substrate holder 2. The result of measurement is shown by the dashed line F in FIG. 10. The graph reveals that the cleaning effect is improved, particularly at positions (3), (2) and (1), and the cleaning result is virtually uniform.
It can be concluded from the above examination that the vacuum chamber is cleaned more evenly by determining the shape of the electric field application electrode such that it applies the electric field over a greater range on the internal wall of the chamber (the internal wall area reached by normals of the electrode surface), and by providing multiple electrodes (one of which can be the substrate holder) and independently controlling the power of the electric field applied to each electrode.
Embodiment 5
FIG. 11 shows the microwave plasma processing apparatus of the fifth embodiment of this invention, which is based on the same principle as the foregoing apparatus, with a difference being that the microwave is introduced into the vacuum chamber in the direction parallel to the substrate surface. The magnetic field is formed in the top-to-bottom direction in the figure as in the foregoing embodiments, but the microwave is perpendicular to the top-to-bottom direction. In the figure, component parts 6', 7', 8' and 11' function identically to those indicated by 6, 7, 8 and 11 in FIG. 1.
In this embodiment, the quartz insulation cover 11' which surrounds the substrate holder 2 has the shape of a frustrum of a cone, with the electric field application electrode 13' having the same shape being attached to it.
It was confirmed for this apparatus that uniform cleaning is achieved when normals of the electrode and substrate holder surfaces reach the entire internal wall surface of the chamber, and the uniformity of cleaning is further improved through the independent control of the power of the electric fields applied to the electrode and the substrate holder.
Embodiment 6
The microwave plasma processing apparatus based on the sixth embodiment of this invention is derived from the one shown in FIG. 9, with the electric field application electrode 13' thereof being divided into sections which are insulated from one another.
It was confirmed for this apparatus that the uniformity of cleaning is further improved through the independent control of the power of the electric field applied to each electrode section.
Embodiment 7
The microwave plasma processing apparatus shown in FIG. 12 (the apparatus of FIG. 2, with a suction port 19 shown being unused in this embodiment) is operated for cleaning a SiO 2 film while applying an electric field of 400 kHz to the substrate holder 2 in the same manner as the first embodiment. Different from the first embodiment in which the magnitude of the applied magnetic field is kept constant during the film forming and cleaning processes, this embodiment is designed to strengthen the magnetic field, lower the location of an electron cyclotron resonance (ECR) region, and move the ECR region in the vertical direction during the cleaning process. Reference numeral 17 in FIG. 12 indicates the position of the ECR region during the film forming process, and reference numeral 18 indicates the top and bottom positions between which the ECR region is moved during the cleaning process.
FIG. 13 shows the result of measurement of the ratio of the amount of etching at cleaning to the amount of SiO 2 deposit after film formation at each measuring position. Indicated by A and C are the cleaning results with and without the application of an electric field which ions can follow, and indicated by G is the result with the application of an electric field which ions can follow and with moving the ECR region during the cleaning process. The graph reveals that the cleaning effect is particularly prominent in the portions of the chamber internal wall and holder side wall where the ECR region comes close and highly excited fluorine ions are generated by it.
It can be concluded from the above examination that the cleaning effect is further improved by repositioning the ECR region from the location for film formation to the location close to the wall surface where cleaning is generally difficult.
Embodiment 8
FIG. 12 shows the cross section of the principal portions of the microwave plasma processing apparatus based on the eighth embodiment of this invention. This embodiment is derived from the apparatus shown in FIG. 2, with a suction port 19 being added to the vacuum chamber 5, and remaining portions are identical to those of FIG. 2.
Experiments with a cleaning process were conducted with this apparatus in the same manner as in the previous embodiment of FIG. 2. In this case, particles in the vacuum chamber are drawn out through the suction port 19 and a differential evacuation device (not shown) connected to the suction port 19, and are subjected to mass analysis during the cleaning process.
The m/e value (m: mass of the particles, e: electric charge of the electron) was measured for each kind of particle. The value for O 2 varied most prominently during the cleaning process. FIG. 14 is a graph showing the result of the measurement, on which the m/e value is plotted on the vertical axis and the time elapsed since the beginning of cleaning is plotted on the horizontal axis. Indicated by A and C are the trends of the m/e value without and with the electric field application, respectively, with the ECR region being located as shown by 17 in FIG. 12. Indicated by G is the trend of the m/e value with the electric field application and with the ECR region being moved between the positions indicated by 18 in FIG. 12. Time points indicated by Ea, Ec and Eg on the trend curves A, C and G are presumed end points of cleaning.
The measurement results in conjunction with the graph of FIG. 13 reveal that the case G of the most uniform and fast etching completes the cleaning in the shortest time, and the cleaning end point is the most pronounced. In this case, the cleaning process was terminated at the end point Eg to inspect the interior of the vacuum chamber, and no residual contaminants were found. In the cases A and C, the end points Ea and Ec are somewhat obscure. In these cases, the cleaning process was terminated at the end points Ea and Ec, respectively, to inspect the interior of chamber, and a small amount of residual contaminants were found on the side wall of the substrate holder.
These measurement results suggest that the state of cleaning can be known from the trend of particle existence in the vacuum chamber during the cleaning process and that uniform cleaning can be achieved by controlling the operational parameters such that the trend curve bends sharply. It was confirmed that the observation of particles based on the emission spectrum of the plasma revealed a cleaning effect that is consistent with the result of the mass analysis.
Embodiment 9
For the microwave plasma processing apparatus of the previous eighth embodiment, the electric field application condition and ECR region moving condition that provide the strongest emission spectrum and the sharpest bend of the trend curve in the cleaning process were selected and input into the control program for the apparatus. As a result of the film forming process and the cleaning process based on this control program, high-quality semiconductor devices could be manufactured on a large production scale without leaving corrosion on the internal wall of the vacuum cleaner.
Embodiment 10
FIG. 15 shows the cross section of the principal portions of the microwave plasma processing apparatus based on the tenth embodiment of this invention. The apparatus is derived from the ones shown in FIGS. 9 and 11, with the electric field application electrode being modified.
The electric field application electrode 13" of this apparatus is designed to move vertically inside the apparatus. When the electrode is not being used, it is located around the substrate holder as shown by the dashed lines, and during the cleaning process, it is positioned opposing the upper tapered portion, for example, of the vacuum chamber as shown by the solid lines. The electrode position is finely adjusted according to the cleaning condition. For example, in case a deposit on the wall surface of the tapered portion is not easily removed, the electrode is brought close to that portion.
Although the foregoing embodiments are for cleaning of the interior of the vacuum chamber after the formation of a SiO 2 film on a substrate based on microwave plasma CVD using electron cyclotron resonance in the presence of a magnetic field, the present invention can also be applied effectively to a cleaning process after the formation of other thin films such as high dielectric oxide films including a SiN film, a TiO 2 film, a TIN film and a PbTiO 3 film, oxide films for superconducting devices, organic films used for etching, and to a cleaning process for an etching apparatus.
The present invention can also be applied effectively to a microwave plasma processing apparatus which operates in the absence of a magnetic field. | A microwave plasma processing apparatus is provided with a vacuum chamber, a substrate holder for mounting a substrate to be processed, a reactive gas feed port, a cleaning gas feed port, a plasma generation device for generating a processing plasma from the reactive gas and a cleaning plasma from the cleaning gas, and a high-frequency electric field application device for applying an electric field having a frequency that allows ions in the cleaning plasma to follow changes in the electric field. The high-frequency electric field application device is activated to apply the electric field to the cleaning plasma so as to remove substances that have been deposited on the surfaces of the vacuum chamber and substrate holder due to the processing of the substrate by the processing plasma, thereby cleaning up the vacuum chamber and substrate holder. | 8 |
FIELD AND BACKGROUND OF THE INVENTION
This invention relates to bicycle powered mower apparatus. More particularly, the invention relates to mower apparatus adapted to receive and be powered by a conventional bicycle.
Pedal operated lawn mowers are known in the art. For example, U.S. Pat. No. 4,455,816 (Porath) describes a tricycle frame which provides basic support for the pedal operated mower. Porath recites a tricycle frame having a front wheel and a pair of rear wheels with the mower cutting blades located between the rear wheels. A chain extends between a pedal sprocket and a rear axle sprocket, and pedaling the bicycle results in rotation of the blade as well as the wheels. The mower of Porath is a composite unit with a bicycle and mower integrated into a single entity.
U.S. Pat. No. 4,341,058 (Chun) describes a pedal powered bicycle mower apparatus including a mainframe and a centrally positioned cutting apparatus mounted on the frame. The cutting apparatus is driven by a series of gears which translate force from the pedals into rotational movement of a cutting blade about a vertical axis to the longitudinal axis of the main supporting frame. Chun describes a bicycle mower apparatus which also comprises a single unit with the mower apparatus forming an integral part of the bicycle.
U.S. Pat. No. 3,630,010 (Rester) describes a multiple use mini-bike for road or trail, having lawn and soil treating and cutting attachments. The Rester device is a motorized vehicle, with the drive motor 22 being secured to the frame. The mini-bike includes a motor 64 which can be attached to the bike and drive motor by means of a flexible coupling 78. The mower 64 is power driven by the motor 22 and there is no connection and operation between the movement of the blade of the mower and rotation of the wheels of the mini-bike.
SUMMARY OF THE INVENTION
The present invention provides a bicycle powered mower apparatus, the mower apparatus being releasably attachable to a conventional bicycle, wherein the mower blades are driven by rotation of one of the wheels of the bicycle, or the sprocket wheel.
According to one aspect of the invention, there is provided a bicycle powered mower comprising: a mower frame; a pair of rear wheels mounted on an axle near the rear of the mower frame; bicycle support means on the mower frame for releasably receiving a bicycle having a frame, front wheel, rear wheel, and front fork; drive means for driving the mower frame over a surface; and a cutter blade assembly operatively connected to the drive means for selectively activating the cutter blade assembly.
Preferably, the mower frame is substantially rectangular and further comprises a pair of front wheels, which may be operated by a steering mechanism to permit steering of the mower frame. The steering mechanism may include a bracket for connection to the front fork of a bicycle so that the front wheels can be steered by steering the bicycle.
The bicycle support means may comprise a ball pivot support bracket for supporting the frame of the bicycle and a steering support bracket for connection to the front fork of the bicycle.
Preferably, the drive assembly comprises a main drive roller for supporting and remaining in fixed contact with the rear wheel of the bicycle and a transmission assembly between the main drive roller and the rear wheels for transmitting motive force from the main drive roller to the rear wheels to drive the mower frame. The transmission assembly may comprise a first gear train between the drive roller and the rear wheels to drive the mower frame in a reverse direction and a second gear train between the drive roller and the rear wheels to drive the mower frame in a forward direction. Preferably, the first and second gear trains include first and second drive sprockets respectively, each drive sprocket being mounted on the rear wheel axle.
The first gear train may comprise a series of sprockets and chains between the drive roller and the rear axle, and the second gear train comprises a series of sprockets and chains between the first gear train and the rear axle.
Each drive sprocket preferably has associated connecting means fixed to the axle to which the drive sprocket can be releasably connected, the drive sprocket being movable between a first position wherein the sprocket is connected to its associated connecting means and thereby rotates the axle when driven, and a second position wherein the drive sprocket is disconnected from its associated connected means and, when rotated, rotates freely about the axle, the drive sprocket being normally biased into the second position. The connecting means may comprise a fixed member attached to the rear axle, a drive pin extending outwardly from the fixed member and a drive pin receiving hole in the drive sprocket for receiving the drive pin when the drive sprocket is in the first position. Conveniently, control means for moving the drive sprocket between the first and second positions are provided, the control means including a pivotal lever one end of which is adjacent the drive sprocket, the other end of which can be operated to move the drive sprocket between the first and second positions.
Preferably, the cutter blade assembly comprises a rotatable blade member mounted to the frame by a bracket, a fixed blade and height adjustment means. The cutter blade assembly may be driven by a chain/sprocket system with a clutch mechanism. The cutter assembly may also comprise a lift cable whereby the blade member can be raised and lowered, wherein raising the blade member reduces the distance between the blade member and the drive means and causes slack in the belt.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of a first embodiment of a bicycle powered lawn mower of the present invention;
FIG. 2 is a top view of the bicycle powered lawn mower shown in FIG. 1;
FIG. 3 is a rear view of the bicycle powered lawn mower shown in FIG. 1.
FIG. 4 is a top view of the clutch mechanism in the bicycle powered lawn mower;
FIG. 5 is a side view of the drive sprocket shown in FIG. 4 of the drawings;
FIG. 6 is a detailed side view showing the mower blade attachment;
FIG. 7 is a side view of a second embodiment of a bicycle powered lawn mower of the invention;
FIG. 8 is a third embodiment of a bicycle powered lawn mower of the invention;
FIG. 9 is a fourth embodiment of the bicycle powered lawn mower of the invention;
FIG. 10 is a fifth embodiment of the bicycle powered lawn mower including a grass catcher tray;
FIG. 11 is a sixth embodiment of the bicycle powered lawn mower including an inertia flywheel;
FIG. 12 is a seventh embodiment showing multiple size sheaves on the mower blade drive to optimize rotational blade speed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, and particularly FIGS. 1, 2 and 3, there is shown a bicycle powered lawn mower 10 comprising a main mower frame 12 to which a bicycle 14 can be releasably attached. The bicycle 14 comprises a bicycle frame 16, a front wheel fork 18, a rear wheel 20, saddle 22, and steering bar 24. Conventional means of propulsion are provided in the form of pedal sprocket 26, rear wheel sprocket 28, and chain 30. Other features, such as brakes, gears and the like, may also be included in the bicycle but for convenience are not described or shown in the present drawings.
The mower frame 12 of the bicycle powered lawn mower 10 comprises a substantially rectangular frame 32 having a pair of substantially parallel side beams 34 and 36, a front beam 38 and a rear beam 40. The front beam 38 constitutes a mount to which front wheels 42 are connected at pivot 44. Spaced a short distance from the rear beam 40, there is provided a rear axle 46 and a rear wheel 48 is mounted on each side of the main frame 12 at each end of the rear axle.
A main drive roller bar 50 is fixed between side beams 34 and 36. A first mesh gear bar 52 and a second mesh gear bar 54 are also located between the side beams 34 and 36 forwardly of the main drive roller bar 50. A pair of bicycle rear axle supports 56 and 58 are mounted on side beams 34 and 36 respectively, the bicycle rear axle supports being adapted to receive and firmly hold the rear axle 28 and sprocket 29 of the bicycle. This is best seen in FIGS. 1 and 3 of the drawings.
A bracket support bar 60 extends between side beams 34 and 36 forwardly of the first mesh gear bar 52. The bracket support bar has located at approximately its mid-point a bracket 62, the bracket 62 having a ball pivot 64. The ball pivot 64 is adapted to receive and support the bicycle frame 16 as can be clearly seen in FIG. 1 of the drawings.
Towards the front of the mower frame 12, there is mounted a mower blade assembly 66, which can be raised and lowered. The mower blade assembly 66, as well as its driving mechanism and raising/lowering mechanism, is described in further detail below.
A steering system 68 is provided for steering the front wheels 42. The steering system 68 includes a steering beam 70 adapted to be fixed at its one end to the front wheel fork 18 of the bicycle. At its other end, the steering beam 70 has a pair of steering bars 72 and 74 extending to each of the front wheels 42 respectively. In a conventional manner which will not be described herein, adjustment of the steering beam 70 results in concomitant movement of the steering bars 72 and 74, which, through the various pivot connections steer the front wheels. The present invention may, however, use any other steering mechanism which may be convenient.
A main drive roller 76 is mounted on the main drive roller bar 50. When mounted on the mower frame 12, the rear wheel 20 of the bicycle is in contact with the main drive roller 76, best illustrated in FIG. 1 of the drawings. The bicycle rear axle supports 56 and 58 are fixed to the rear wheel axle 28 of the bicycle in such a way as to insure that the rear wheel is firmly in contact with the main drive roller 76. The main drive roller 76, when rotated, drives a shaft 78 and sprocket 80.
The first mesh gear bar 52 has mounted thereon a first mesh gear 82 and a shaft 84. The second mesh gear bar 54 has mounted thereon a second mesh gear 86 and a shaft 88. The first mesh gear 82 and second mesh gear 86 are of a size and spaced from each other such that they are permanently engaged.
The main drive roller 76 drives shaft 78 and sprocket 80. A chain 90 extends between the sprocket 80 and a sprocket 92 on the shaft 88. At the other end of the shaft 88, there is a sprocket 94, and a chain 96 extends from the sprocket 94 to a reverse drive sprocket 98 mounted on the rear axle 46 in a manner to be described below. It is to be noted that the second mesh gear 86 is fixedly mounted on the shaft 88 so that when the shaft 88 is turned by the sprocket and chain assembly (80, 92 and 90), the second mesh gear 86 rotates and, since it engages with the first mesh gear 82, rotates the first mesh gear 82 in a direction opposite to that of second mesh gear 86.
The first mesh gear 82, when rotating, rotates the shaft 84. At one end of the shaft 84 there is mounted a sprocket 100. A chain 102 extends from the sprocket 100 to a forward drive sprocket 104 mounted on the rear axle 46 in a manner to be described below.
The other end of the shaft 84 includes a sprocket 106, and a mower belt chain drive 108 extends from the sprocket 106 to the mower sprocket 110. In this way, the rear wheel of the bicycle, in a manner to be described below, is capable of driving the mower blade assembly 66.
The main drive roller 76 is mounted on the main drive roller bar 50 in a manner which insures proper contact with the rear wheel 20 of the bicycle. Extending upwardly from the main drive roller bar 50 are a pair of upstanding supports 112 and 114 between which the main drive roller 76 is supported. A pressure spring 115 is located between the main drive roller bar 50 and the lower part of the main drive roller which urges the main drive roller 76 upwardly or towards the rear wheel 20 of the bicycle. In this way, a positive engagement between the main drive roller 76 and the rear wheel of the bicycle 20 is facilitated. Further, the main drive roller 76 is constructed or layered with a material which maximizes traction between the rear bicycle tire and the roller so that slippage is reduced as much as possible. In this way, the maximum amount of energy delivered from the rear wheel 20 of the bicycle is transmitted to the main drive roller 76 and the driving assembly on the mower frame 12.
The mower blade assembly 66 will now be described with particular reference to FIG. 6 of the drawings. The assembly 66 comprises a rotary blade drum 116 having a series of angled blades 118 attached thereto. Rotation of the blade 116 over a lawn surface causes the lawn to be cut in conventional manner. The blade drum 116 is mounted to the side beams 34 and 36 of the mower frame 12 by means of a support bracket 120. The support bracket comprises an upper portion 122 and a lower portion 124 at an angle thereto, the blade drum 116 being pivotally mounted on the lower portion 124 of the support bracket 120. The upper portion 122 includes a cylindrical sleeve assembly 126 and a spring 128, which insure that the belt tension is maintained, and that the proper cutting height is achieved when the blade drum 116 is lowered as described below. A fixed blade 130 is mounted on a bracket 132, and cooperates with blades 118 to cut the lawn. The bracket 132 is mounted in a slot 134 of a descending arm 136 on the frame 34 and is held in the slot by bolt assembly 138 which slides in the slot permitting the mower assembly 66 to be raised and lowered. The bracket 132 also supports a roller 140 which moves over the surface thereby insuring proper height adjustment of the blades with respect to the grass.
The blade drum 116 has a mower sprocket 110. A mower belt drive 108 extends between the sprocket 110 and the sprocket 106 mounted at the end of the shaft 84. Rotation of the first mesh gear 82 causes rotation of the shaft 84, whereby the sprocket 106 is rotated to drive the mower belt drive 108 and ultimately the blade drum 116.
The support bracket 120 is fixed to the frame 34 such that the height of blade drum 116 can be set and fixed. A bracket 146 having a slot 148 is attached to the upper portion 122, and also to the frame 34. A bolt 150 extends through the slot 148, and when the blade drum 116 is at the desired height, having been adjusted by upward or downward movement of the upper portion 132 and bracket 146, the bracket 146 is fixed relative to the frame 34 by tightening the bolt 150. Reference is now made to FIGS. 4 and 5 of the drawings, showing the drive sprocket and clutch mechanism as described above. A reverse drive sprocket 98 and a forward drive sprocket 104 are mounted on the rear axle 46. Since each drive sprocket 98 and 104 respectively causes the axle to rotate in a different direction, a clutch mechanism is provided whereby the operator can select either the reverse drive sprocket or the forward drive sprocket to drive the axle, with the other sprocket being disconnected. The following describes the forward drive sprocket 104 but the identical structure pertains with respect to the reverse drive sprocket 98.
The forward drive sprocket 104 comprises a circular disk portion 152 having at its periphery a plurality of radially outwardly projecting teeth 154. The disk portion 152 has equispaced therein four or more drive pin holes 156, a bore 158 at the center of the sprocket 104 and a bearing 160 located therein. The chain 102 engages the teeth 154 of the sprocket 104 in conventional manner.
The sprocket 104 is mounted on the rear axle 46 such that the axle passes through the bore 158. The sprocket 104 is free to slide along the axle 46 and rotates freely thereon. Adjacent the sprocket 104 is a fixed member 162 fixed to the axle 46. A drive pin 164 extends outwardly from the fixed member 162 and is the same distance from the outer periphery of the rear axle 46 as are the pin holes 156 in the drive sprocket 104. A spring 166 is located between the drive sprocket 104 and fixed member 162, and, under normal circumstances, urges the drive sprocket 104 away from the fixed member 162. When the drive sprocket is not engaged with the fixed member, with the drive pin 164 located in a pin hole 156, it rotates free about the axle 46.
An engage lever 168 is provided whereby the drive sprocket 104 can be brought into engagement with the fixed member 162. The engage lever 168 is pivotally mounted at pivot point 170. One end 172 of the engage lever 168 abuts a throw-out bearing 174, while the other end 176 is fixed to a cable 178. The cable extends along the mower frame 12, and connects to a control lever 180 located within easy access of the operator. Movement of the control level pivots the engage lever 168 through the action of the cable 178 and brings the drive sprocket 104 into engagement with the fixed member 162. When the control lever 180 is released, the engage lever 168 moves back to the position shown in FIG. 4 of the drawings and the action of the spring 166 urges the drive sprocket away from the fixed member 162, thus disengaging the drive sprocket 104 and fixed member 162. In this position, the drive sprocket 104 moves freely about the axle 46 without rotating it, while in the engaged position with the fixed member 162, rotation of the drive sprocket 104 causes rotation of the axle 46. A similar structure and operation prevails with respect to the reverse drive sprocket 98, the description of which will not be repeated.
OPERATION
The front wheel of a bicycle is removed and the front wheel fork 18 of the bicycle is fixed to the steering beem 70. The bicycle frame 16 is positioned such that it rests on the ball pivot 64 of bracket 62 while the rear wheel 20 rests on the main drive roller 76. As mentioned above, the main drive roller 76 is urged upwardly by the action of the spring 115 to insure a solid traction between the tire of the rear wheel 20 and the main drive roller 76. The bicycle lawn mower is now ready for use, and peddling the bicycle sets the apparatus in motion.
The rotation of the rear wheel 20 causes the main drive roller 76 to rotate in the direction indicated by arrow A in FIG. 1. The main drive roller 76 drives shaft 78 and sprocket 80. A chain 90 extending between sprocket 80 and sprocket 92 causes rotation of the shaft 88 and the second mesh gear 86. The second mesh gear rotates in the direction shown by arrow B in FIG. 1 of the drawings. Rotation of the shaft 88 causes rotation of sprocket 94 and the chain 96, which extends between the sprocket 94 and the reverse drive sprocket 98 on the rear axle 46, causes rotation of the reverse drive sprocket 98. The reverse drive sprocket 98, when not engaged with its corresponding fixed member will simply rotate freely about the axle 46 and do no work. When the reverse drive sprocket 98 engages with its fixed member, it will cause the reverse drive sprocket 98 to rotate in the direction indicated by arrow C of the drawings, and the rear axle 46 and rear wheels will rotate in the same direction which results in the bicycle powered lawn mower moving in the reverse direction.
The first mesh gear 82, by virtue of its engagement with the second mesh gear 86, is caused to rotate. Rotation of the first mesh gear 82 cause the shaft 84 to rotate as well as the sprocket 100. The chain 102 between the sprocket 100 and the forward drive sprocket 104 causes the forward drive sprocket 104 to rotate in the opposite direction to that of the reverse drive sprocket 98. Thus, when the forward drive sprocket is engaged with the fixed member 162 the rear wheels 48 will be caused to rotate and move the bicycle powered in the forward direction.
The shaft 84, rotated by the first mesh gear 82, also rotates sprocket 106. The mower belt drive 108 drives the mower sprocket 110 which in turn drives the rotor blade wheel 116.
When it is desired to move the bicycle powered lawn mower over a surface where no cutting is required, the mower blade assembly 66 can be raised by means of a lift cable 182 (see FIG. 6). The lift cable 182 may be mounted on the control lever 180 so that it is within easy reach of the operator. At the same time, the mower blade assembly is raised, the chain drive system is disengaged from the fixed member 162. Another blade drive assembly would utilize the following setup. When the blade drum 116 is in the raised position, the belt tension becomes slackened due to reduced linear center to center distance between the drive pulley 110 and the sprocket 106. In this way, the blade drum 116 will not be rotated and unnecessary energy not dissipated. When the blade 116 is lowered using the lift cable 182, the belt is tightened since the center to center distance is increased. Tightening of the belt engages the blade drum 116 which is therefore rotated. An idler pulley may be provided to retain the alignment of the belt 108 when slack. The idler pulley (not shown) may be located at any convenient point along the length of the lower belt drive 108.
With reference to FIG. 7, there is shown a second embodiment of the invention. A bicycle powered lawn mower 210 comprises features in most ways identical to that described in the previous embodiment, except that the rear wheel 20 of the bicycle has been removed. In this embodiment, the rear wheel axle 212 is mounted on a support 214, and the existing bicycle chain is engaged with a first mesh gear 216 and the second mesh gear 86 by means of a chain 218. In this embodiment, the main drive roller is eliminated, and the second mesh gear is driven directly through the chain linkage. In FIG. 8, it is to be noted that the rear wheel 28 of the bicycle is in contact with the ground 220 and that the mowing blade assembly 66 is driven by a chainbelt 222 which extends from the rear axle 46. In this way, the rear wheel of the bicycle directly drives the entire apparatus, and the various rollers, sprockets and chains are eliminated.
In FIG. 9, yet a further embodiment of the invention is disclosed wherein both wheels remain on the bicycle. The front wheel is in direct contact with the ground, and steers the mower apparatus, while the rear wheel 28 contacts and drives a main drive roller 76, with associated transmission, as described above. The front portion of themower frame is supported by connection to the bicycle frame 16 at point 316.
In FIG. 10, a bicycle powered lawn mower of the invention is shown which includes a grass catcher tray 222 which is releasably fixed to the mower frame 12. The tray 222 is located behind the bracket 132 so that grass blades cut by blade drum 116 and blade 118 move into the tray 222.
With reference to FIG. 11 of the drawings, a bicycle powered lawn mower of the invention includes an inertia flywheel 224 located on the shaft 78 of the main drive roller 76. The inertia flywheel 224 smooths out pedaling and facilitates the smooth movement of the mower.
In FIG. 12 of the drawings, there is shown multiple size sheaves which may be used on the mower blade drive system to optimize the rotational blade speed with respect to ground cover. The operator may therefore select the most convenient ratio so that the blades will rotate at a speed most suitable in the circumstances.
The invention is not limited to the precise constructional details described above or illustrated in the drawings. For example, instead of using gear sprockets and chains, a belt in each instance may be used which moves over a sheave or pulley wheel. | A bicycle powered lawn mower comprises a mower frame, to which is attached a rear axle carrying a pair of rear wheels. The mower frame includes bicycle support brackets whereby a bicycle can be releasably received on the frame. A drive is provided whereby the mower frame can be transported over a surface. The mower frame further comprises a cutter blade assembly operatively connected to the drive so that the blade assembly can be selectively activated or deactivated. | 0 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to solutions for winding coils of core components of dynamoelectric machines, and more particularly to apparatuses for winding stator cores, like those employed in brushless motors.
[0002] Although the invention is particularly described with reference to stator cores, the principles of the invention are equally applied to other cores that need to be wound with wire conductor.
[0003] With brushless motors it is known to use cores having wire coils wound by moving one or more needles to dispense tensioned wire. To form a coil having a plurality of turns the wire exits the moving needles and becomes appropriately positioned in the core. The needles move for a predetermined number of cycles to generate a certain number of complete turns, which form the finished wound coils.
[0004] The cycle accomplished by a needle is normally a combination of reciprocating translations, reciprocating rotations and incremental radial movements, as described for example in publication EP 1191672.
[0005] Schematically, a turn of a coil is a closed rectangular extension of wire having two rectilinear sides joined by two shorter sides. In general, a series of turns forming a coil consist o a plurality of the rectangular extensions piled in an orderly manner with the sides positioned consistently.
[0006] By piling of the coils in an orderly manner, the space occupied by the coil in the core results optimized, therefore interference contact of the turns with the surrounding structure is avoided.
[0007] Normally, the two long sides of the rectangular extension of the coil are produced by the axial translations accomplished by the needles dispensing the wire. The rotation movements accomplished by the needles dispense the wire to form the two lateral stretches, which are usually the short sides of the coils. The incremental radial translations pile the turns in different planes of the coil, i.e. at various depths of the slots of the core—a phenomena usually referred to as “stratification” of the turns.
[0008] The needles are moved with kinematic solutions driven by rotation of an input motor to accomplish the foregoing movements, like is described in the above mentioned EP 1191672.
[0009] In publication EP 318 063 a more limited solution is described. In this case the needles do not move in the radial direction to achieve the stratification.
[0010] The different kinematic solutions existing in the art significantly influence both the precision with which the needles are positioned to form the coils, and also the speed with which the needles move to dispense the wire.
[0011] In other words, the kinematic solutions are important not only for the precision with which the turns become positioned in the coil, but also for the time required to place all the turns to form the finished coils. This is particularly influenced by the mechanical transmissions, the tolerances, the inertia of the parts of the various kinematic solutions, and also due to the position of theses inertias in space.
[0012] The winding requirements of coils in brushless cores are particularly focused on positioning of the turns with the maximum precision within the available space of the core of the electric machine. At the same time, higher speed of the movement of the needles is required to increase productivity. The end result is a production of wound cores at high speed with the coils being compact and having a high number of turns.
[0013] A further objective is that the movement of the needles needs to be easily and accurately adjusted to adapt the winding parameters to a wide variation of core configurations. In particular, the translation movements, the rotation movements, and the radial displacement of the needles respectively need to cover paths, accomplish angles and travel at slot depths that allow the coil turns to be precisely positioned within specific geometries of the cores.
[0014] For the same reason, these movements of the needles need to be accomplished in different stages of a temporal cycle, which is required to wind the coils.
[0015] Based on the foregoing description, it is an object of the present invention to provide an improved apparatus for winding electric machine coils.
[0016] It is also a particular object of the invention to provide an improved apparatus that causes the needles to accomplish translation movements, rotation movements and radial movements with more accurate positioning of the needles during the winding stages.
[0017] It is also an object of the present invention to provide an improved apparatus for accomplishing the translation movements, the rotation movements and the radial movements of the needles at a higher speed to increase the productivity of wound coils.
[0018] It is also an object of the present invention to provide an apparatus that has solutions which are easily adjustable for winding different core configurations, whilst maintaining the foregoing advantages of positioning accuracy and high speed movement of the needles.
[0019] A further object of the invention is to provide an apparatus that is more simple to manufacture due to the low number of parts, and for the fact that the parts are of simple configuration and can be easily assembled.
SUMMARY OF THE INVENTION
[0020] The invention relates to a novel solution having movable members (needles) for dispensing wire to form the wire coils in the winding stage by translating in an axial direction with respect to the core, rotating with respect to the core, and translating in a radial direction with respect to the core.
[0021] A first tubular member, which supports at least one wire dispensing member, can translate in the axial direction and rotate with respect to the core. Furthermore, a second tubular member can be assembled coaxially with respect to the first tubular member and can rotate with respect to the first tubular member to radially translate the wire dispensing member in relation to the core.
[0022] Means are provided for converting the relative rotation between the first tubular member and the second tubular member to translate the wire dispensing member in the radial direction with respect to the core.
[0023] The invention is also applicable in the case of multiple wire dispensing members, which can be supported by the first tubular member to be translated in the axial direction and rotated with respect to the core.
[0024] Similarly, the multiple wire dispensing members can be translated in the radial direction with respect to the core by rotating the second tubular member with respect to the first tubular member.
[0025] Each of the wire dispensing members can release wire in order to form a coil around a respective pole of the core. In this way, multiple coils can be wound simultaneously.
[0026] These and other objects are accomplished by means of the apparatus according to claim 1 .
[0027] Other characteristics of the invention are indicated in the dependent claims.
[0028] Further characteristics of the invention, its nature and various advantages will result more clearly from the enclosed figures and the following detailed description of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] In the enclosed figures:
[0030] FIG. 1 is a partial section elevation view of the apparatus for moving the wire dispensing members according to the principles of the present invention;
[0031] FIG. 2 is a partial section view as seen from directions 2 - 2 of FIG. 1 ;
[0032] FIG. 3 a is a partial view as seen from directions 3 of FIG. 1 illustrating a lever mechanism. The upper part of the lever mechanism is a view from directions 3 ′- 3 ? of FIG. 4 . In FIG. 3 a certain parts of the apparatus of FIG. 1 have been omitted for reasons of clarity.
[0033] FIG. 3 b is a view similar to the view of FIG. 3 a with the lever mechanism of the apparatus positioned differently with respect to the position of FIG. 3 a.
[0034] FIG. 4 is a partial section view of the area 4 of FIG. 1 . FIG. 4 is similar to FIG. 1 of publication EP 1191672, however in the solution of FIG. 4 of the present invention certain modifications are present, as is described in this application.
[0035] FIG. 5 is a view similar to the view of FIG. 3 a , although illustrating a different embodiment of the invention.
[0036] FIG. 6 is a view as seen from directions 6 - 6 of FIG. 4 in the case of the embodiment of FIG. 5 .
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0037] FIG. 1 illustrates a first assembly 10 comprising a needle 11 for dispensing wire W to wind coils around the poles of a core.
[0038] The needle 11 translates with reciprocating motion in directions T and T′, parallel to longitudinal axis 12 . In addition needle 11 rotates with an angular alternative motion in directions S and S′ around longitudinal axis 12 and translates with forward and backward radial motion in directions R and R′, which are perpendicular to axis 12 .
[0039] The trajectory accomplished by needle 11 is similar to the trajectory of the needle described in publication EP 1191672. Relative rotations between the external tube 13 and the internal tube 14 in directions S and S′ (see also FIG. 4 ) obtain that needle 11 translates in the radial directions R and R′ for stratification. The relative rotations of external tube 13 and internal tube 14 are generated by motor 60 , which transmits rotations in the directions S and S′ to internal tube 14 through assembly 118 (see FIGS. 1 and 4 ) to achieve the stratification displacements in directions R and R′.
[0040] The principles of this transmission are similar to those described in publication EP 1191672—see FIG. 1 of this publication where motor 164 is similar to motor 60 of the present application, whilst assembly 118 and assembly 126 of FIG. 1 of publication EP 1191672 are respectively similar to assemblies 118 and assembly 126 of FIGS. 1 and 4 of the present application.
[0041] With reference to FIGS. 1 and 4 of the present invention, tubes 13 and 14 are assembled integral with each other for translating together in directions T and T′, therefore, the motion of translation backwards and forwards in the directions T and T′ of needle 11 parallel to longitudinal axis 12 occurs by translating tubes 13 and 14 together in directions T and T′.
[0042] This translation is generated by assembly 16 comprising arm 15 , which is connected through moveable hinge 17 (shown with dashed line in FIG. 1 ) to internal tube 14 . The ring 16 ′ (shown with dashed line in FIG. 1 ) is assembled inside arm 15 to be coaxial with axis 19 of shaft 20 , and is caused to rotate together with shaft 20 by means of the connection to sleeve 51 through lever 50 . In fact, sleeve 51 is integral with shaft 20 in the rotation direction around axis 19 , whilst for the adjustment of the translation path in directions T and T′ (see the following), sleeve 51 is able to move parallel to axis 19 due to the key and slot connection 51 ′.
[0043] Assembly 16 , and thus arm 15 , accomplishes the oscillations OS and OS′ around axis 18 of the pin present on shaft 20 due to the rotations of ring 16 ′ in arm 15 , and the inclined position of arm 15 caused by the position of sleeve 51 along shaft 20 . Axis 18 is positioned perpendicular to axis 19 of main shaft 20 . The oscillations OS and OS′ of arm 15 are transformed into backwards and forward translations in directions T and T′ of the internal tube 14 , and therefore also into backward and forward translations in directions T and T′ of external tube 13 . Assembly 16 , arm 15 , and hinge 17 are similar to the assembly that generate the translations in publication EP 318 063—see FIG. 1 of this document, however, in the present case hinge 17 is also capable of allowing the rotations of shaft 14 in directions S and S′.
[0044] Shaft 20 is assembled on bearings 21 and 22 to rotate around axis 19 and thus generates the oscillations OS and OS′ of arm 15 . In particular, motor 24 and the belt transmission 23 (see also FIG. 2 ) rotate shaft 20 around axis 19 to generate the oscillations OS and OS′. Therefore, motor 24 indirectly obtains the forward and backward translations in directions T and T′ of the needles like 11 . With reference to FIG. 1 , gear wheel 25 assembled on the end of shaft 20 engages with the gear wheel 26 assembled on the input shaft 27 of cam assembly 28 . As shown in FIGS. 1 and 2 , cam assembly 28 comprises a support frame 29 fixed by bolts to the main frame 30 of the apparatus of FIG. 1 . The view of assembly 28 in FIG. 1 is obtained by removing lid 29 ′ from the joining surface 29 ″ (see FIG. 2 ).
[0045] With reference to assembly 28 , the input shaft 27 is assembled on bearings 31 , which in turn are assembled on frame 29 . Conjugated cams' 32 and 33 are assembled on input shaft 27 of assembly 28 . Rollers 32 ′ and 33 ′, which are assembled on respective arms 32 ″ and 33 ″, are in rolling contact with surfaces of cams 32 and 33 , respectively.
[0046] With reference to FIG. 2 , arms 32 ″ and 33 ″ are assembled on exit shaft 35 of assembly 28 . The exit shaft 35 is assembled on bearings 36 , which are in turn assembled on frame 29 .
[0047] With reference to FIGS. 1 , 3 a and 3 b , an end of lever 38 of lever mechanism 37 is fixed to arm 39 , which in turn is assembled on exit shaft 35 of assembly 28 . Fixing of lever 38 to arm 39 can be accomplished by means of a flange connection using bolts 40 , as shown in FIGS. 3 a and 3 b.
[0048] Lever 38 is connected to lever 41 by means of the moveable hinge 42 . Hinge 42 comprises a slide 43 assembled to rotate on the end of lever 38 . Slide 43 is able to move in slot 44 of lever 41 during the rotations RO of lever 38 around axis 35 ′ caused by rotation of exit shaft 35 of assembly 28 , as shown in FIGS. 3 a and 3 b.
[0049] The end of lever 41 is connected to gear wheel 46 of FIG. 4 to rotate tube 14 in directions S and S′. The connection of lever 41 to gear wheel 46 is achieved by means of a flange using bolts 45 , as shown in FIG. 4 .
[0050] Rotation of cams 32 and 33 obtained by the rotation of shaft 20 , as is required to accomplish the winding cycles, obtains rotations S and S′ of arm 41 around axis 12 . Rotations S and S′ are synchronized with the translations in directions T and T′ of tubes 13 and 14 .
[0051] Therefore, assembly 28 by having its own frame 29 , where bearings 31 and 36 of the shafts of cams 32 and 33 are supported, can be considered an independent unit that is assembled separately and then bolted to frame 30 , as shown in FIG. 2 . This solution can facilitate manufacture and assembly of the apparatus of FIG. 1 .
[0052] As an alternative embodiment, frame 29 can be omitted. In this case, the bearings of shafts 27 and 35 can be assembled on needed supports of main frame 30 .
[0053] The transmission formed with gear wheels 25 and 26 and the position of assembly 28 locates axis 27 ′ of input shaft 27 and all of assembly 28 near to base 30 ′ of the apparatus. In other words, axis 27 ′ has been displaced on the lower side of shaft 20 , whilst tubes 13 and 14 are located on the upper side of shaft 20 . In this way, the distance that separates axis 19 of shaft 20 from axis 12 has been reduced, therefore the distance that separates axis 12 from the base 30 ′ of the apparatus has been reduced. This has achieved that the apparatus of FIG. 1 has a low height from base 30 ′ and the moments of force generated by the translation of inertias in directions T and T′ with respect to base 30 ′ have been reduced. Therefore, the speed of the apparatus as generated by motor 24 can be increased. At the same time, a higher speed of the synchronization of motor 60 with motor 24 has been increased.
[0054] By substituting arm 39 with similar arms, which differently distance hinge 42 from exit shaft 35 , it is possible to change the angles of rotations S and S′ for winding cores having for example different pole widths. Bolt assembly 39 ′ of an arm 39 is necessary for the adjustment of the distance of hinge 42 because it is able to position the positioning head 39 ″ at different distances. Positioning head 39 ″ is received in a slot of an arm 39 (see FIGS. 1 , 3 a and 3 b ) to position lever 38 with respect to the arm 39
[0055] To adjust the distance which the needle 11 accomplishes in directions T and T′, in other words, to change the translation path of the needle, for example when the length of the poles of the cores changes, the inclination of arm 15 around pin 18 is modified, which requires modifying the inclination of ring 16 ′ with respect to shaft 20 by using assembly 58 . To achieve this, lever 50 is hinged at one the end to ring 16 ′ of assembly 16 , whilst the other end of lever 50 is hinged to sleeve 51 . Sleeve 51 can move when required (during adjustments) along shaft 20 , i.e. parallel to axis 19 .
[0056] Cylinder 52 is threaded on the outside, and this thread of cylinder 52 engages the thread present inside gear ring 53 , as shown in FIG. 1 . By rotating gear ring 53 around axis 19 , cylinder 52 translates parallel to axis 19 to displace sleeve 51 by means of the engagement connection 52 ′ of cylinder 52 inside the slot of 51 , as shown in FIG. 1 .
[0057] The key 54 existing between cylinder 52 and support 55 guarantees that cylinder 52 does not rotate, but only translates parallel to axis 19 when arm 15 needs to be inclined. Gear ring 53 can be rotated for predetermined angles by a pinion (not shown) which is rotated by motor 56 (see FIG. 2 ).
[0058] To adjust the path of the needles in directions R and R′ for the stratification, programming of motor 60 needs to be changed. The new programming needs to guarantee the synchronization with the translations and rotations generated by motor 24 .
[0059] FIG. 5 shows an embodiment where levers 41 and 38 of the embodiment of FIG. 3 a have been substituted with a gear train 220 . More particularly, gear 200 is connected to gear wheel 46 of FIG. 4 to rotate tube 14 in directions S and S′. The connection of gear 200 to gear wheel 46 is achieved by means of a flange abutment using bolts like 45 shown in FIG. 4 .
[0060] Gear 201 meshes with gear 200 as shown in FIG. 5 . Gear 201 is free to rotate (idle) on shaft 202 , as is more fully explained with reference to FIG. 6 .
[0061] Gear 203 is fixed on the end of shaft 35 of cam assembly 28 by means of coupling 204 .
[0062] Therefore, rotations of shaft 35 deriving from rotation of cams 32 and 33 are transmitted to gear wheel 46 through the gear train 220 consisting of gears 203 , 201 and 200
[0063] With reference to FIG. 6 , collar 206 , lever 208 and the assembly of shaft 209 are shown. These parts and assembly are only partly shown in FIG. 4 for reasons of clarity.
[0064] More particularly only collar 206 is shown with dash line representation.
[0065] Again with reference to FIG. 6 , collar 206 is assembled to rotate on cylinder 205 of FIG. 4 around axis 12 . Collar 206 is provided with extending portion 206 ′, where shaft 202 is fixed by means of a clamp connection closed by bolt 202 . In this way gear 201 is supported to rotate on shaft 202 , which is integral with collar 206 .
[0066] Lever 208 is hinged to portion 206 ′ and to the end of shaft 209 , as shown in FIG. 6 . Head 209 ′ of shaft 209 is clamped between cylinder 210 and 211 by means of bolts 212 which are threaded into frame 30 , as shown in FIG. 6 . By substituting cylinder 210 with other cylinders having a different length L from abutment surface 30 a of frame 30 , the position of gear wheel 201 can be changed, as shown by the examples of the two positions in dash line 201 ′ and 201 ″.
[0067] The position of gear wheel 201 can be changed when substituting gear wheel 203 with other gear wheels for achieving different gear ratios (see dash line representation of substituted gears 35 a and 35 b ), as is required to change to angles of rotation in directions S and S′. | An apparatus for moving wire dispensing members used to wind dynamo electric machine coils comprising a frame; a first tubular member having a longitudinal axis assembled for longitudinal reciprocation parallel to said longitudinal axis; a second tubular member assembled for longitudinal reciprocation and rotational oscillation; means for generating the translational reciprocation motion of said first and second tubular members; means for generating rotational oscillation of said first and second tubular members; means for generating a relative rotational motion between the first and second tubular members for accomplishing a radial motion of the wire dispensing members; wherein the means for generating the translational reciprocation motion are assembled on a first shaft and the means for generating rotational oscillation are supported for the rotational oscillation with support means assembled on the frame, and the means for generating the rotational oscillation derive rotational motion from the first shaft through a transmission joint. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part application of U.S. patent application Ser. No. 08/311,943, entitled “WATER TREATMENT APPARATUS”, filed Sep. 26, 1994, the disclosure of which is incorporated herein by reference now U.S. Pat. No. 5,635,063.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a water treatment apparatus. More particularly, the present invention relates to a multi-stage water treatment apparatus. Even more particularly, the present invention relates to a multi-stage water treatment apparatus for producing potable water.
2. Prior Art
As disclosed in the above referred to co-pending application, a need exists for water treatment systems that remove organic, inorganic, radiological, and microbiological contaminants from water, thereby rendering the water suitable for human consumption. The co-pending application teaches a water treatment apparatus that removes these contaminants by passing the water through a housing comprising two chambers, each of which contains a plurality of layers of treatment materials; these treatment materials include silver impregnated activated carbon, activated carbon, iodine resin, and a mixed bed of cationic and anionic resins. While the water treatment apparatus of the co-pending application is efficacious, further experimentation has revealed that its usefulness may be improved by adding more and different layers of treatment material in different configurations, and by enabling continuous, as well as batch, filtration.
SUMMARY OF THE INVENTION
The present invention provides a water treatment apparatus which removes a broad range of contaminants and which may be gravity fed or pressure fed. The water to be treated may be derived from any source, including ponds, lakes, condensation such as that from an air conditioner, etc.
The apparatus hereof, generally, comprises:
(a) a first housing portion comprising:
(i) a top surface, the top surface having a water inlet formed therein;
(ii) a cylindrical sidewall integrally formed with the top surface and depending therefrom;
(iii) a bottom surface integral with the sidewall and extending therefrom, the bottom surface having a recess formed therein, the recess having a plurality of holes formed therein, the holes defining means for providing a long dwell time;
(b) a second housing portion comprising: a cylindrical side wall having an upper edge and terminating at a housing outlet;
(c) means for detachably connecting the first housing portion and the second housing portion such that the recess of the first housing portion is housed within the second housing portion;
(d) at least one treatment section disposed within the first housing portion;
(e) at least one treatment section disposed within the second housing portion;
(f) at least one porous separator disposed in each housing portion, the at least one porous separator removing impurities from water and regulating water flow through each of the treatment sections; and
wherein water flows into the water inlet, through each of the treatment sections in at least one of the housing portions, through the at least one porous separator, and exits at the housing outlet.
The claimed invention presents a water treatment apparatus that removes organic, inorganic, radiological, and microbiological contaminants from water.
In a first sediment hereof, in order to ensure complete treatment of the water fed into the system, the water treatment apparatus includes a plurality of housing portions, ranging from at least two up to about six housing portions, that are sealably, removable connected, the housing portions being separable depending on the quality of the incoming water. Disposed within each housing portion is at least one treatment section. In a two-housing portion array, preferably, a first housing portion includes a “Halogen Removal and pH Neutralization Section” and a “Microbiological Treatment Section,”and a second housing portion includes an “Iodine Removal Section ” and an “Organic, Inorganic, and Radiological Removal Section.” The first housing portion is separable from the second portion and, depending on the quality of the water to be treated, may be bypassed, thereby passing water through only the second housing portion, if there are few enough contaminants in water entering the system that the treatments of the first and second sections are not needed.
In a six-housing portion array, preferably, a first housing portion includes a “Pretreatment Section”; a second housing portion includes a “Microbiological Treatment Section”; a third housing portion includes an “Iodine Dwell Section”; a fourth housing portion includes an “Iodine Removal Section”; a fifth housing portion includes a “pH Neutralization and Organic Removal Section”; and a sixth housing portion includes an “Inorganic and Radiological Removal Section.” The housing portions are all separable from each ether and, depending on the quality of the water to be treated, any may be bypassed, thereby passing water through only the remaining housing portions, if there are few enough contaminants in water entering the system that the treatments of various sections are not needed.
The source of water may be a water supply tank which gravity feeds the apparatus hereof. Alternatively, a forcing means such as a pump or a faucet attachment with a flow regulator may be used to force water through the treatment sections. Water is fed into the forcing means by a connection to any source of water, including a condenser of an air conditioner, a vehicle radiator, a natural source such as a lake or pond, brackish water, etc. The forcing means forces water from the water source through the treatment housings, where treatment occurs as described hereinabove.
In a second embodiment hereof, the housing portions are separate and distinct and are interconnected by fluid delivery conduits. In this embodiment, the water to be treated is forced through the system by forcing means, such as a pump, a faucet attachment with a slow regulator, or the like. As in the first embodiment, water is fed into the forcing means by a connection to any source of water, including a condenser of an air conditioner, a vehicle radiator, a natural source such as a lake or pond, brackish water, etc. The forcing means forces water from the water source through the treatment housings, where treatment occurs as described hereinabove.
In each embodiment, water flows into the treatment housing through the housing inlet, passes through the water treatment media, the filtering media, and the water flow control media, eventually passing out of the housing via the housing outlet.
The present invention will be more clearly understood with reference to the accompanying drawings. Throughout the figures, like reference numerals refer to like parts in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of a water treatment apparatus in accord with a first embodiment of the present invention;
FIG. 2 is a side view of a second housing portion of the first embodiment of the water treatment apparatus hereof;
FIG. 3 is an environmental view of the first embodiment of the water treatment apparatus hereof;
FIG. 4 is a cross-sectional view of the water treatment apparatus taken along line 4 — 4 of FIG. 3;
FIG. 5 is a cross-sectional view of a first means for lengthening dwell time used in the practice hereof;
FIG. 6 is a cross-sectional view of a second means for lengthening dwell time used in the practice hereof;
FIG. 7 is a cross-sectional view of a portion of a treatment housing of a water treatment apparatus in accord with the first embodiment of a water treatment apparatus;
FIG. 8 is a cross-sectional view of the upper stacked housing portions of a water treatment apparatus in accord with the present invention;
FIG. 9 is a cross-sectional view of the lower stacked housing portions of a water treatment apparatus in accord with the present invention; and
FIG. 10 is an environmental view of a second embodiment of a water treatment apparatus in accord with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIGS. 1 and 2, and as disclosed and shown in the co-pending application, there is depicted therein a first embodiment of the present invention generally, depicted at 12 , which functions in conjunction with a water supply tank 14 and a water collection tank 16 .
The water treatment apparatus 12 includes a generally cylindrical housing 18 . The housing, preferably, comprises a first generally cylindrical housing portion 20 and a second generally cylindrical housing portion 22 . Both housing portions are formed from water impermeable material, and are constructed as disclosed in the co-pending application. The housing portions 20 , 22 are removably sealably interconnected, as disclosed in the co-pending application.
Disposed within each of the housing portions 20 , 22 is at least one and, preferably, a plurality of treatment sections, each treatment section comprising at least one discrete particulate layer. The treatment sections cooperate to help rid water of impurities such as bacteria, heavy metals, chlorine, etc. At least one of the treatment sections in the second housing member defines means for removing organic, inorganic, and radiological contaminants. The specific constituents of the treatment sections, their functions, and their relative positioning within the housing 18 will be discussed further.
As shown in FIG. 3, the water supply tank 14 seats atop the top surface 24 of the housing 18 and the water collection tank seats below the housing 18 . These are attached and cooperate as disclosed in the co-pending application. Water flows from the water supply tank 14 through the water treatment apparatus 12 and is collected in the water collection tank 16 .
FIG. 4 depicts the various distinct treatment sections within the housing 18 of the water treatment apparatus 12 , and the particulate layers that form the treatment sections. Each of the layers has a diameter substantially equal to the diameter of the housing, ensuring that water flows through each of the layers and does not leak in any space between the housing and the respective layer. The first housing portion 20 of the housing 18 , which serves as the top of the housing 18 , includes a topmost layer comprising a separator member, such as a plastic disk 80 having a multiplicity of holes 82 formed therethrough. The holes are evenly distributed on the disk and control the flow of water through the apparatus 12 . The disk 80 functions to disperse water flowing in through the housing inlet 30 and to reduce the flow rate of the water through the treatment apparatus 12 . The disk 80 is seated between two radially inwardly directed shoulders 87 , 89 which hold the disk 80 in place. The disk 80 has a diameter substantially equal to that of the first housing portion 20 , ensuring that water flows through the plurality of holes 82 formed through the disk 80 . It is vital to the function of the water treatment apparatus 12 that water flowing through each of the layers is dispersed and permeates throughout each layer. This helps to increase the life of the water treatment apparatus, generally, by causing water to flow throughout each layer, instead of forming channels within each layer, reducing the life of an individual layer and, thusly, the life of the water treatment apparatus.
The plastic disk 80 is located a distance from the top surface 24 of the first housing member 20 . This provides a small reservoir area 84 within the first housing member for holding water received through the housing inlet 30 and helps prevent water from backing up into the water supply tank 14 .
Disposed below the plastic disk 80 is a first treatment section which is, preferably, a “Halogen Removal and pH Neutralization Section.” The first treatment section has a first separator, preferably a first filter paper 85 , and includes layers one through three as described hereinafter. The first filter paper 85 filters out and traps large impurities in the water. Additionally, the first filter paper 85 serves to help distribute the water within the first housing member 20 , in the same manner as noted above. Any type of filter paper may be used herein and includes felt filter paper, nylon filter paper, and other filter paper known to the skilled artisan. All of the filter paper referred to herein may be one of these types of filter paper. Additionally, each piece of filter paper serves to slow the progress of water through the water treatment apparatus 12 and has a diameter substantially equal to that of the housing ensuring water does not leak around the edges of the filter paper. Some pieces of filter paper may be thicker or thinner, depending upon the flow rate required to achieve sufficient contact time between the water and the discrete layer disposed above the filter paper.
Beneath the first filter paper 85 is a layer of silver impregnated, activated carbon (silver carbon) 86 . The silver carbon 86 primarily serves to remove chlorine from water passing therethrough. The silver blocks the growth of bacteria within the activated carbon layer 86 . If bacteria were to grow in the activated carbon layer 86 , the water treatment apparatus 12 would function inefficiently. Silver carbon is a well-known and commercially available product, such as that sold by Bestech, Inc.
Beneath the silver carbon layer 86 , a second filter paper 90 is disposed which aids in distributing water flow and filters out any silver or carbon particulates which become entrained in the water. As shown, a layer of activated carbon 92 is disposed below the second filter paper 90 . This layer filters out any remaining chlorine in the water. The activated carbon layer 92 also removes any chloromethane that might be present, which is a source of unpleasant odor in water. Activated carbon is, also, a commercially available product, such as that sold by the Calgon Carbon Corporation. The carbon further serves to protect the silver carbon 86 from Redox Alloy in a later layer, as described hereinbelow. This protection is needed because Redox Alloy that comes in contact with silver carbon will strip silver from the silver carbon.
Below the layer of activated carbon 92 is disposed a third filter paper 94 . The third filter paper 94 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the third filter paper 94 is a layer of Redox Alloy 96 . Redox Alloy is a well-known and commercially available product; one example is KDF, which is manufactured by KDF Fluid Treatment. The Redox Alloy will kill any microbiological contaminants in the water. The layer 96 of Redox Alloy completes the first treatment section.
Disposed below the first treatment section, still within the first housing portion 20 , is a second treatment section, a “Microbiological Treatment Section.” The second treatment section starts with a fourth filter paper 98 , and includes layers four and five as described hereinbelow. The fourth filter paper 98 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the fourth filter paper 98 is a layer of iodine particles or resin 100 . The iodine particles or resin, which may be of the trivalent, pentavalent, or septavalent variety or a combination of these, serves to kill microbiological contaminants in the water, such as viruses and bacteria. Iodine particles or resin with an odd valence are used because the intramolecular bonds of such molecules are weaker than those of iodine molecules with an even valence, and the weaker bonds will allow the iodine to attack microorganisms more quickly. Odd-valence iodine is a well-known and commercially available product; one example is MCV resin, sold by Umpqua Research Company. A hybrid of odd-valence and even-valence iodine may also be used. Also, an optional second layer of iodine (not shown) may also be used.
Below the layer of iodine particles or resin 100 is disposed a fifth filter paper 102 . The fifth filter paper 102 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the fifth filter paper 102 is disposed, as a fifth treatment layer, means for lengthening dwell time 103 . The means for lengthening dwell time 103 may comprise any suitable construction for holding the water for an extended period of time. For example, the means 103 may comprise an elongated tube 105 , as shown in FIG. 5, or a retention cup or tank l 06 , as shown in FIG. 6 . The means for lengthening dwell time 103 may contain a layer of iodine particles or resin.
If the means for lengthening dwell time 103 contains a layer of iodine particles or resin, the means 103 should be sufficiently large to allow a dwell time of about 1 to 10 minutes before the water passes from the means 103 to the next layer, depending on the iodine concentration in the water. Adjusted iodine concentrations of less than 0.9 ppm should not be used.
If the means for lengthening dwell time 103 does not contain a layer of iodine particles or resin, the only iodine in the water is what is the water from the previous layer 100 brings with it. The means 103 should be sufficiently large to allow a dwell time of 8 to 10 minutes before the water passes from the means 103 to the next layer.
As shown in FIG. 6, at least one probe 108 may be used to measure the iodine concentration in the means for lengthening dwell time 103 . A timer 109 in communication with the at least one probe 109 calculates the necessary dwell time by the formula “dwell time =60 minutes divided by ppm of iodine.”The means for lengthening dwell time 103 completes the second treatment section, and is the last treatment section in the first housing portion 20 . As discussed hereinabove, the first housing portion 20 may be removed, thereby passing water through only the second housing portion 22 , if there are few enough contaminants in water entering the system that the treatments in the first housing portion 20 are not needed.
Disposed below the second treatment portion, within the second housing portion 22 , is a third treatment section, an “Iodine Removal Section.” The third treatment section starts with a sixth filter paper 108 and includes layers six through eight, as described hereinafter. The sixth filter paper 108 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the sixth filter paper 102 is disposed a layer 110 of anionic resin in the chloride form. Anionic resin in the chloride form is a well-known and commercially available product: one example is Iodosorb II, sold by Umpqua Research Company. Anionic chloride removes iodine and iodide from the water.
Below the anionic resin 110 is disposed a seventh filter paper 112 . The seventh filter paper 112 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the seventh filter paper 112 is disposed a layer of silver carbon 114 . The silver carbon removes iodide from the water.
Below the silver carbon 114 is disposed an eighth filter paper 116 . The eighth filter paper 116 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the eighth filter paper 116 is disposed a layer of activated carbon 118 . The activated carbon removes iodine from the water.
The activated carbon 118 may have silver carbon admixed therewith. This is necessary if the water has high levels of microorganisms, to prevent microorganism growth from occurring on the activated carbon 118 .
The layer of activated carbon 118 completes the third treatment section. Disposed below the third treatment section, still within the second housing portion 22 , is a fourth treatment section, an “Organic, Inorganic, and Radiological Removal Section.” The fourth treatment section starts with a ninth filter paper 120 and includes layers nine through fifteen, as described hereinafter. The ninth filter paper 120 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the ninth filter paper 120 is disposed a layer of activated carbon 122 . The activated carbon protects the anionic resin layer 110 and the silver carbon layer 114 from Redox Alloy in a later layer, as described hereinbelow. This protection is needed because Redox Alloy that comes in contact with the anionic resin layer 110 will strip chloride therefrom, and Redox Alloy that comes in contact with the silver carbon layer 114 will strip silver from the silver carbon. Alternately, the layer 122 may consist of a mixture of cationic resin in the hydrogen form and activated carbon. This latter mixture may also contain silver carbon,
Below the activated carbon 122 is disposed a tenth filter paper 124 . The tenth filter paper 124 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the tenth filter paper 124 is disposed a layer 126 of Redox Alloy. The Redox Alloy removes inorganic contaminants from the water and neutralizes pH in the water. The pH neutralization is necessary for implementation of an ion exchange resin layer in a later step to work, as described hereinbelow. The Redox Alloy also kills any microbiological contaminants in the water, which may have been introduced by trace microbiological contaminants in the water growing on the layers of activated carbon 118 and 122 . Activated carbon may also be admixed with the Redox Alloy in this layer.
Below the Redox Alloy 126 is disposed an eleventh filter paper 128 . The eleventh filter paper 128 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the eleventh filter paper 128 is disposed a layer of activated carbon 130 . The activated carbon protects the ion exchange resin in a later layer, as described hereinbelow, from the Redox Alloy 126 ; the activated carbon removes “glue taste,” which might have been introduced into the water by the Redox Alloy 126 , from the water; and the activated carbon removes organic contaminants from the water.
Below the activated carbon 130 is disposed a twelfth filter paper 132 . The twelfth filter paper 132 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the twelfth filter paper 132 is disposed a layer of ion exchange resin 134 . The ion exchange resin 134 is a mixed bed resin of cationic and anionic resins. The mixed bed resin is a well-known and commercially available product; one example is Nm60-SG, sold by Sybron Chemicals. The ion exchange resin 134 removes inorganic and radiological contaminants from the water.
If the water entering the system is hard, i.e. has high levels of Ca++, Mg++, etc., the mixed bed resin is mixed with activated carbon in the layer 134 . If the water entering the system is very hard, i.e. has very high levels of Ca++, Mg++, etc., then a water softener layer is substituted for the ion exchange layer 134 . Suitable water softeners are well-known and commercially available; one example is that sold under the designation C-249, by Sybron Chemicals. If the water entering the system is extremely hard, i.e. has extremely high levels of Ca++, Mg++, etc., the water softener is mixed with activated carbon in the layer 134 . Water hardness is calculated by dividing the total dissolved solids (TDS) in ppm by 17.1; this calculation gives grains of hardness per gallon.
Turning now to FIG. 7, if the water entering the system is very hard or extremely hard, and water softener with or without activated carbon is used as the layer 134 as described hereinabove, then below the layer 134 is disposed a thirteenth filter paper 136 . The thirteenth filter paper 136 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the thirteenth filter paper 136 is disposed a layer of activated carbon 136 . The activated carbon 138 protects the water softener in the layer 134 from Redox Alloy in a later layer, as described hereinbelow.
Disposed below the activated carbon 138 is a fourteenth filter paper 140 . The fourteenth filter paper 140 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the fourteenth filter paper 140 is disposed a layer of Redox Alloy 142 . The Redox Alloy removes inorganic contaminants from the water and neutralizes pH in the water. The pH neutralization is necessary for the water leaving the system to be potable. The Redox Alloy also kills any microbiological contaminants in the water, which may have been introduced by trace microbiological contaminants in the water growing on the layer of activated carbon 138 .
Below the Redox Alloy 142 is disposed a fifteenth filter paper 144 . The fifteenth filter paper 144 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the fifteenth filter paper 144 is disposed a layer of activated carbon 146 . The activated carbon removes “glue taste” which might have been introduced into the water by the Redox Alloy 126 , from the water.
The layer of activated carbon 146 , or the ion exchange layer 134 , if the incoming water is not hard enough to necessitate the thirteenth through fifteenth particulate layers, completes the fourth treatment section. Disposed below the fourth treatment section, still within the second housing portion 22 , is a sixteenth filter paper 148 . The sixteenth filter paper 148 serves further to distribute water flow and to filter out any impurities that may have passed through the previous filter papers. Below the sixteenth filter paper 148 , water then flows from the water purification apparatus through the downwardly extending spout 56 into the water collection tank 16 through the aperture 74 in the top 72 of the water collection tank 16 . A user may then remove the water collection tank 16 from the water purification apparatus and utilize the water collection tank 16 as a pitcher for pouring water into an appropriate drinking apparatus such as a glass or a mug.
It is to be appreciated that the construction hereof enables the “stacking ” of housing portions to tailor the filtering to be effected. Thus, and turning now to FIGS. 8 and 9, there is shown this stacking of sections of treatment material, comprising more distinct particulate layers, disposed within the housing 18 . As shown in FIGS. 8 and 9, the housing 18 comprises six housing portions 201 , 211 , 221 , 231 , 241 , 251 . The housing portions are shaped as are the housing portions in the first embodiment, each having a cylindrical sidewall defining a hollow interior. The housing portions are removably sealably interconnected to one another as described hereinabove. Each housing portion houses one treatment section. The treatment materials in the distinct particulate layers making up the treatment sections are the same as the treatment materials in the embodiments described hereinabove, and their purposes are the same as those described hereinabove; therefore, in the interest of efficiency, only the composition of the various treatment sections and constituent particulate layers in the second embodiment, and not their purposes, will be discussed hereinbelow. The housing portions 201 , 211 , 221 , 231 , 241 , 251 are separable and stackable in prescribed order as indicated above, thus passing incoming water through more or fewer treatment sections as necessary depending on the quality of the incoming water. As in the two housing portion array described hereinabove, a layer of filter paper is, preferably, disposed between every two adjacent layers of treatment material, though most of the filter papers may be dispensed within a less-preferred embodiment. At a minimum, there should be one layer of filter paper per section, as described hereinbelow.
In a six-housing portion array, disposed below the plastic disk 80 in the first housing section 201 is a first treatment section, a “Pretreatment Section.” The first treatment section starts with a first filtering layer 200 , the first filtering Layer 200 containing filter paper 202 .
Below the first layer 200 is a first treatment layer 204 , the first treatment layer 204 containing silver carbon 206 .
Below the first treatment Layer 204 is a second treatment layer 208 , the second treatment layer 208 containing activated carbon 210 .
Below the second treatment layer 208 is a third treatment layer 212 , the third treatment layer 212 containing a combination of silver carbon and activated carbon 214 .
Below the third treatment layer 212 is a fourth treatment layer 216 , the fourth treatment layer 216 containing Redox Alloy 218 .
Below the fourth treatment layer 216 is a fifth treatment layer 220 , the fifth treatment layer 220 containing a combination of Redox Alloy and activated carbon 222 . The fifth treatment layer completes the first treatment section.
Below the first treatment section is a second treatment section, a “Microbiological Treatment Section.” The second treatment section is housed within the second housing portion 211 . The second treatment section starts with a sixth treatment layer 224 , the sixth treatment layer 224 containing iodine particles or resin 226 , the iodine particles or resin 226 being in the trivalent, pentavalent, or septavalent form or a combination of these. A hybrid of odd-valence and even-valence iodine may also be used. Also, an optional second layer of iodine (not shown) may also be used.
Below the sixth treatment layer 224 is a second filtering layer 228 , the second filtering layer 228 containing filter paper 230 . The second filtering Layer completes the second treatment section.
Below the second treatment section is a third treatment section, an “Iodine Dwell Section.” The third treatment section is housed within the third housing portion 221 . The third treatment section starts with a seventh treatment layer 232 , the seventh treatment layer 232 containing means for lengthening dwell time 234 , as described hereinabove and shown in FIGS. 5 or 6 .
Below the seventh treatment layer 232 is a third filtering layer 236 , the third filtering layer 236 containing filter paper 239 . The third filtering layer completes the third treatment section.
Below the third treatment section is a fourth treatment section, an “Iodine Removal Section.” The fourth treatment section is housed within the fourth housing portion 231 . The fourth treatment section starts with an eighth treatment layer 240 , the eighth treatment layer 240 containing anionic resin 242 .
Below the eighth treatment layer 240 is a ninth treatment layer 244 , the ninth treatment layer 244 containing silver carbon 246 .
Below the ninth treatment layer 244 is a tenth treatment layer 248 , the tenth treatment layer 248 containing activated carbon 250 .
Below the tenth treatment layer 248 is an eleventh treatment layer 252 , the eleventh treatment layer 252 containing a combination of silver carbon and activated carbon 254 .
Below the eleventh treatment layer 252 is a twelfth treatment layer 256 , the twelfth treatment layer 256 containing a combination of activated carbon and anionic resin 258 .
Below the twelfth treatment layer 256 is a thirteenth treatment layer 260 , the thirteenth treatment layer 260 containing anionic resin followed by a combination of silver carbon and activated carbon 262 .
Below the thirteenth treatment layer 260 is a fourth filtering layer 264 , the fourth filtering layer 264 containing filter paper 266 . The fourth filtering layer completes the fourth treatment section.
Below the fourth treatment section is a fifth treatment section, a “pH Neutralization and Organic Removal Section.” The fifth treatment section is housed within the fifth housing portion 241 . The fifth treatment section starts with a fourteenth treatment layer 268 , the fourteenth treatment layer 268 containing Redox Alloy 270 . Alternately, the fifth treatment section may start with a layer of activated carbon (not shown) preceding the fourteenth treatment layer 268 containing Redox Alloy 270 . Also, activated carbon may be admixed with the Redox Alloy in this layer.
Below the fourteenth treatment layer 268 is a fifteenth treatment Layer 272 , the fifteenth treatment layer 272 containing activated carbon 274 .
Below the fifteenth treatment layer 272 is a sixteenth treatment layer 276 , the sixteenth treatment layer 276 containing silver carbon 278 .
Below the sixteenth treatment layer 276 is a seventeenth treatment layer 280 , the seventeenth treatment layer 280 containing a combination of Redox Alloy and activated carbon 282 .
Below the seventeenth treatment layer 280 is an eighteenth treatment layer 284 , the eighteenth treatment layer 284 containing a combination of silver carbon and activated carbon 286 .
Below the eighteenth treatment layer 284 is a nineteenth treatment layer 288 , the nineteenth treatment layer 288 containing Redox Alloy followed by a combination of silver carbon and activated carbon 290 .
Below the nineteenth treatment layer 288 is a fifth filtering layer 292 , the fifth filtering layer 292 containing filter paper 294 . The fifth filtering layer completes the fifth treatment section.
Below the fifth treatment section is a sixth treatment section, an “Inorganic and Radiological Removal Section.” The sixth treatment section is housed within the sixth housing portion 251 . The sixth treatment section starts with a twentieth treatment layer 296 , the twentieth treatment layer 296 containing mixed bed resin 298 .
Below the twentieth treatment layer 296 is a twenty-first treatment layer 300 , the twenty-first treatment layer 300 containing water softener 302 .
Below the twenty-first treatment layer 300 is a twenty-second treatment layer 304 , the twenty-second treatment layer 304 containing Redox Alloy 306 .
Below the twenty-second treatment layer 304 is a twenty-third treatment layer 308 , the twenty-third treatment layer 308 containing activated carbon 310 .
Below the twenty-third treatment layer 308 is a twenty-fourth treatment layer 312 , the twenty-fourth treatment layer 312 containing a combination of mixed bed resin and activated carbon 314 .
Below the twenty-fourth treatment layer 312 is a twenty-fifth layer 316 , the twenty-fifth treatment layer 316 containing a combination of Redox Alloy and activated carbon 318 .
Below the twenty-fifth treatment layer 316 is a twenty-sixth treatment layer 320 , the twenty-sixth treatment layer 320 containing a combination of Redox Alloy and activated carbon followed by mixed bed resin 322 .
Below the twenty-sixth treatment layer 320 is a twenty-seventh treatment layer 324 , the twenty-seventh treatment layer 324 containing a combination of water softener and activated carbon 326 .
Below the twenty-seventh layer 324 is a twenty-eighth treatment layer 328 , the twenty-eighth treatment layer 328 containing a combination of Redox Alloy and activated carbon followed by water softener 330 .
Below the twenty-eighth treatment layer 328 is a sixth filtering layer 332 , the sixth filtering layer 332 containing filter paper 334 . The sixth filtering layer completes the sixth treatment section.
Below the sixth treatment section, water then flows from the water purification apparatus through the downwardly extending spout 56 into the water collection tank 16 through the aperture 74 in the top 72 of the water collection tank 16 . A user may then remove the water collection tank 16 frog the water purification apparatus and utilize the water collection tank 16 as a pitcher for pouring water into an appropriate drinking apparatus such as a glass or a mug.
As noted hereinabove, the number of housing portions can be added or subtracted depending on the quality of the water to be treated.
In a second embodiment hereof, and with reference to FIG. 10, a forcing means, such as a pump 400 , a faucet attachment with a flow regulator (not shown), or the like is deployed to force water through a treatment housing 405 . Water is fed into the forcing means from a collector 402 which collects water from any suitable source (not shown). Suitable sources include, for example, and as contemplated herein, a condenser of an air conditioner, a vehicle radiator, etc. In this manner, potable water may be obtained during, for instance, an automobile trip in which the automobile's air conditioner is used.
The forcing means forces water from the water source (not shown) through the treatment housing 405 , where treatment occurs via separate treatment sections, each treatment section comprising distinct particulate layers as described hereinabove. In this embodiment, as gravity is not used to feed water through the apparatus, the portions of the housing 405 need not be vertically stacked as in the first and second embodiments, but may be configured in any suitable way. Preferably, the housing 405 comprises a plurality of housing sections 406 , 410 , 414 , 418 connected to each other via fluid delivery conduits or hoses 404 , 408 , 412 , 416 , respectively, with treated water exiting the treatment housing 405 via an outlet hose or pipe 420 .
Adding a forcing means to the first embodiment is also envisioned. This would allow the housing sections of the first embodiment to be connected in configurations other than vertical stacking.
As will be realized, the invention is capable of other and different embodiments and its several details are capable of modifications in various obvious respects, all without departing from the invention. | A water treatment apparatus including a housing comprising multiple housing portions and a plurality of treatment sections disposed within the housing, each treatment section comprising at least one distinct particulate layer. The apparatus is designed so that no water pressure need be applied to force the water through the apparatus, as gravity pulls the water down through the filtering layers. Water may also be force fed through the treatment apparatus; when the water is force fed, the housing portions need not be vertically stacked, but may be configured in any suitable arrangement. The treatment sections are distributed through the various housing portions in logical groups to perform various kinds of filtering. The housing portions are detachable and sealably stackable in multiple configurations, thus passing water through more or fewer treatment layers, depending on the quality of the incoming water. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to a speech-synthesizer timepiece, and more particularly to a speech-synthesizer timepiece capable of providing an audible announcement in advance of and immediately prior to the provision of audible sounds indicative of updated time.
A speech-synthesizer timepiece is well known, for example, U.S. Pat. No. 3,998,045 TALKING SOLID STATE TIMEPIECE by R. W. Lester. Such prior art was adapted to announce current time at preselected points in time by means of audible sounds. However, such prior art suffered from the disadvantages that the user might fail to listen or listen by mistake since audible sounds indicative of current time were provided without any advance announcement. For example, in the case where the audible sounds are automatically provided at an interval of one hour, the user may not be free of mistakes when listening to an audible indication of updated time unless electronic sounds such as onomatopoeic sounds ("peep peep") or words or phrases, such as "it" are provided in advance of the audible indication of updated time to attract the user's attention. Should the user fail to hear the leading sound (say, a consonant), the user would mistakenly misinterpret the audible sound indication. For example, with the audible indication of "five o'clock" ("goji" in Japanese), it is possible that the user may inadvertently hear only "oji" and thus misinterpret it to be "four o'clock" ("yoji" in Japanese).
It is therefore an object of the present invention to provide an improved sound-synthesizer timepiece which prevents the user's failure to hear and accurately interpret audible sounds or which prevents the user's error in dictating the audible sounds by providing advance announcement such as an audible phrase "it is now" or audible causation sounds, such as "peep peep".
For a more complete understanding of the present invention and for further objects and advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a schematic diagram of a speech-synthesizer timepiece according to one preferred embodiment of the present invention;
FIG. 2 is a block diagram of a time information output circuit in the embodiment of FIG. 1;
FIG. 3 is a block diagram of a sound producing circuit in the embodiment of FIG. 1; and
FIGS. 4 and 5 are flow charts for illustration of operation of the embodiment shown in FIGS. 1 through 3.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, there is illustrated, in a schematic representation, a speech-synthesizer timepiece constructed according to one preferred embodiment of the present invention, which is adapted to automatically provide intermittent sounds for advance announcement immediately before an audible indication of updated time.
The illustrative embodiment includes an oscillator OSC for providing a frequency standard, a divider DV for dividing the output of the oscillator and providing different frequency signals Sf and Sg from the middle thereof, an AND logic gate F for producing an intermittent signal Sd based upon a logical sum of the signals Sf and Sg, a generator AO (described in detail later) for producing a signal Sa at a given interval within a limited time allocation and current time information Sb, a delay circuit D for delaying the signal Sa for a given period of time, a flip flop F provided to be set in response to the signal Sa and reset in response to the signal Se, a time announcing sound circuit TVO to be described with respect to FIG. 3, and a sequence control PC for developing commands in response to the signal Se or a keyed input via a time recall key Ko. The embodiment further comprises a low pass filter LPF, a gate circuit G responsive to the set or reset state of the flip flop F to select either an audio output Sc from the low pass filter or an intermittent sound signal Sd for supply to a speaker, Sp, and a driver DR for driving the speaker Sp for releasing the audible sounds indicative of updated time or the intermittent sound signal via the speaker Sp.
The output of the oscillator OSC is divided via the divider DV from the middle of which the two signals Sf, Sg are derived and then introduced into the AND logic gate A. The AND logic gate A provides the intermittent sound signal Sd for one input terminal of the gate circuit G. Upon the development of the signal Sa at the time signal generator AO the flip flip F is placed into the set state, enabling the gate circuit G to select the intermittent sound signal Sd, which actuates the driver DR to release the intermittent sounds from the speaker Sp.
Since the signal Sa from the circuit AO is also supplied to the delay circuit D, the delay circuit D will provide the signal Se after a predetermined period of time, placing the flip flop F into the reset state and enabling the gate circuit G to select the output signal Sc of the low pass filter LPF within the sound circuit TVO. Simultaneously, the sound circuit TVO provides the time information output signal Sc in response to signal Se. The driver DR is actuated by the signal Sc to provide audible sounds indicative of time information from the speaker Sp. Therefore, as long as the delay period is properly established by the delay circuit D, onomatopoeic sounds (for example, can be released in good time immediately before an audible indication of time information, for example, "peep peep", "five o'clock".
Although the audible sounds are provided automatically in the above illustrated embodiment, the audible sounds indicative of current time may be manually recalled by actuation of the key Ko. In this case the flip flop F is placed into the set state to enable the gate circuit G to select Sc from TVO so that the audible sounds are provided in the fashion of "--hour--minute" without any onomatopoeic sounds.
FIG. 2 shows details of an example of the time information generator AO of FIG. 1, which comprises an oscillator CG, a divider DV, a timekeeping counter CO for counting a 1 Hz signal from the divider DV, and a pair of registers TR, TRo for storing time information in the order of hours and minutes.
The register TR, TRo receives the output of the timekeeping counter CO, with the former being reset in response to the output of a judge circuit J 2 and the latter serving as a time register storing current time information.
A register R 1 stores an interval of time announcement (for example, at each hour), a register R 2 stores the beginning of a time zone of the day for time announcement (for example, 8:00 AM of a zone 8"00 AM through 10:00 PM) and a register R 3 stores the end of a time zone of the day for time announcement (in the given example, 10:00 PM).
A decision circuit J 1 detects coincidence between the registers R 2 and TRo or coincidence between the registers R 3 and TRo. The circuit J 1 provides a signal S 1 for the former and a signal S 2 for the latter. A decision circuit J 2 detects coincidence between the contents of the registers R 1 and TR and develops a signal S 3 to reset the register TR in the case of coincidence and hold a signal S 6 at the ground level.
The signal S 5 is the output of the flip flop F which is generated in the development of the output S 1 of the decision circuit J 1 and reset in response to S 2 .
A keyboard TK includes digit keys for the entry of time information. A key control KC establishes the entry introduced via the keyboard TK in either of the registers R 1 , R 2 or R 3 . A change-over switch SE is adapted to select the output of the key control KC and hence select the register for storage of the key entry.
A one-shot pulse generator OM develops the signal S 4 upon actuation of the key K. A time voice alarm circuit TVO is responsive to a logical sum of the signals S 3 and the signal S 4 to develop audible signals indicative of the contents of the timekeeping register TRo.
The timepiece system constructed as above will operate in the following manner.
The switch SE is actuated so as to introduce the output signal of the key control KC only to the register R 2 . Subsequently, the beginning of the time zone for the time announcement mode is entered via the keyboard TK and stored in the register R 2 . The switch SE is then actuated to introduce the output signal of the key control KC only to the register R 3 . In a similar manner, the end of the time zone for the time announcement mode is entered via the keyboard TK and introduced into the register R 3 . Thus, the time zone for the time announcement mode is specified. For example, when it is desired to perform the time announcement mode from 8:00 AM to 6:00 PM, the keys are first actuated in the order of 8 , 0 and 0 and then in the order of 1 , 8 , 0 and 0 .
The interval for the time announcement mode is specified in the following manner. The switch is actuated to select the register R 1 for the entry of a desired interval for the time announcement mode. For example, when it is desired to execute the time announcement mode at each ten minutes, the digit keys 1 and 0 are sequentially actuated. The input signal to the register R 1 actuates the reset circuit RE to place the register TR into the reset state. For this purpose the signal S 3 is developed at each passage of the interval established within the register R 1 .
Therefore, the timepiece receives all necessary items of information in this manner and is ready to perform the time announcement mode. In the given example, updated time is audibly indicated at the end of each ten minutes interval from 8:00 AM until 6:00 PM. In particular, when it is 8:00 AM, time information 8:00 is established within the register TRO and the decision circuit J 1 develops the coincidence output S 1 with R 2 , setting the flip flop F to develop the signal S 5 . The register R 1 , on the other hand, stores the preselected period of ten minutes and places the register TR into the reset state at each lapse of ten minutes. The decision circuit J 2 develops the signal S 3 at each lapse of ten minutes, and thus satisfies a logical sum condition with the output signal S 5 of the flip flop F to make the signal S 6 effective. Such transition of the signal S 6 is sensed by the time voice announcement circuit TVO, enabling the contents of the register TRo to be audibly indicated. The register TR is reset concurrently with the development of the signal S 3 and the decision circuit J 2 senses non-coincidence and stops generating the signal S 3 . Therefore, the signal S 6 is effective for only a moment. In other words, the impulsive signal S 6 is developed at every ten minutes.
Under the circumstances the contents of the register R 3 are exactly in agreement with the contents of the register TRo to thereby enable the decision circuit J 1 to develop the output S 2 to reset the flipflop F. Updated time information is audibly indicated upon the development of the signal S 3 only during the period where the signal S 5 is developed as one of input conditions of the AND logic gates.
In the given example, audible sounds "hachiji reifun (8:00)" are first provided and upon the passage of ten minutes "hachiji jyuppun (8:10)" are provided, followed by the audible indication of "hachiji nijyuppun (8:20)", "hachiji sanjyuppun (8:30)", and so forth.
Upon actuation of the key K, the one-shot circuit OM operates to develop the signal S 4 to enable the current time information at that time to be audibly provided. The contents of the registers R 1 , R 2 , R 3 may be selected at the option of the operator, for example, five minutes or one hour. Any desired time zone of the day may be also established.
When the signal S 6 is made effective, the announcement circuit TVO functions to provide an audible sound indicative of the contents of the register TRo.
FIG. 3 is a schematic block diagram of an example of the time announcement circuit TVO. The register B receives hour information and minute information from the register B, both of which are transferred into a one-digit buffer register D.
The read only memory RM contains sound quantizing data and thus voice elements as listed in Table 1.
TABLE 1______________________________________NA ichi NK hachiNB icchi NL kuNC ni NM kyuhND san NN jyuhNE yo NO jyuNF yon NP jiNG go NQ punNH roku NR funNI rokku NS reiNJ nana______________________________________
In the foregoing Table 1, NA, NB, NC, . . . Nr, NS specify the initial addresses of the respective word elements, which are terminated with an END code. The output Ro of the read only memory RM is developed in a digital fashion and converted into a corresponding analog waveform compatible with voice outputs via a digital-to-analog converter DA and a low pass filter LPF, thereby enabling the speaker SP via the driver DR.
A first voice initial address decision circuit CC establishes the voice initial address according to the contents of the buffer register D for an audible indication of a desired voice, the address data being loaded into the address counter AC. A second voice initial address decision circuit CB specifies a command to be described later. More particularly, the voice word elements "it is now" are established within the BC circuit and loaded into the address counter AC. An adder FA effects addition of "1" on the contents of the address counter AC and thus increments the same. A reset circuit CAC resets the address counter AC and, when the address counter AC is not reset, the read only memory RM does not specify any address. In this manner, by specifying the voice initial address and incrementing the address counter AC, the respective ones of the word elements within the read only memory RM are selected in sequence via the address decoder ADC. The decision circuit T D connected to the buffer register D determines if the contents of the latter are "0" or "1" or "1, 3, 4, 6". The decision circuit J E senses the END code developed from the read only memory RM, RS type flip flops F 1 -F 2 provide various controls and have decision circuits JF 1 -JF 3 for their. The sequential control PC receives the signal S 6 , and the various outputs of the decision circuits J D , J E , J F1 -J F3 , J K , J A and provides commands 1 , 2 , . . . S .
FIG. 4 depicts a flow chart for the development of the advance announcement and the time announcement. Upon actuation of the manual recall key K o the steps are carried out in the sequence of n 1 →n a →n 2 for the audible sounds of "--hour--minute". In the case where the signal Sa is developed from the Ao circuit, the steps n 1 →n 6 →n c →n 2 are selected in sequence with the accompanying audible indication of "it is now" and "--hour--minute". Since details of these events are not of importance to the present invention, the disclose thereof is omitted. See, for example, our copending application Ser. No. 18,174 (our Ref. 1214-USA or GER).
Whereas the present invention has been described with respect to specific embodiments thereof, it will be understood that various changes and modifications will be suggested to one skilled in the art, and it is intended to encompass such changes and modifications as fall within the scope of the appended claims. | A speech-synthesizer timepiece is adapted to produce audible sounds indicative of updated time information at a desired point in time through the use of the speech synthesizing technique. To avoid the user's failure to listen to the audible sounds or to avoid the user's error in dictating the audible sounds, an advance announcement is generated which includes a monotonous sound, a simple phrase or sentence. This advance announcement is provided when the audible sounds indicative of updated time is about to develop. | 6 |
This application is a continuation-in-part of U.S. patent application Ser. No. 12/799,909 filed May 5, 2010 now U.S. Pat. No. 8,133,159 incorporating all of these by reference.
BACKGROUND OF THE INVENTION
1. Field
The present invention relates to a standup exercise apparatus that simulates walking and jogging with arm exercise. More particularly, the present invention relates to an exercise machine having separately supported pedals for the feet and arm exercise coordinated with the motion of the feet where the pedal stride length is determined by the movements of an operator. Crank arms are positioned forward the operator at pedal height.
2. State of the Art
The benefits of regular exercise to improve overall health, appearance and longevity are well documented in the literature. For exercise enthusiasts the search continues for safe apparatus that provides full body exercise for maximum benefit in minimum time.
Recently, a new category of exercise equipment has appeared on the commercial market called varying stride elliptical cross trainers. These cross trainers guide the feet along a closed loop shaped curve to simulate the motions of jogging and climbing with varying stride lengths. The shorter stride lengths have pedals which follow up and down curves that are generally arcuate in shape causing difficult startup. The longer stride lengths have pedals which follow closed loop curves having more of a banana shape than elliptical. There is a need for a variable stride exercise apparatus capable of long, medium and shorter stride lengths where the pedals always follow generally elliptical curve paths with easy startup.
Varying stride elliptical cross trainers are shown without cams in Rodgers, Jr. US Patent Applications 2009/0181828 and 2009/0156369 as well as U.S. Pat. Nos. 7,828,698, 7,520,839 and 7,530,926 which show a pendulum striding exercise apparatus having a foot support members hung from a generally horizontal beam pivoted to achieve the varying stride length pedal curves. Rodgers, Jr. in US Patent Application 2009/0156370 and U.S. Pat. No. 7,507,184 show exercise apparatus with flexible support elements having varying stride lengths. Miller in U.S. Patent Applications 2009/0105049 and 2011/0172062 also shows an exercise apparatus having varying stride lengths. Eschenbach in U.S. Pat. Nos. 7,841,968, 7,938,754 and 8,029,416 shows user defined motion elliptical exercise apparatus with a default elongate curve for easy starting. Chuang et al. in U.S. Pat. No. 7,608,018 shows a front drive user defined motion elliptical apparatus. Grind in U.S. Pat. No. 7,922,625 shows an adaptive motion exercise device with oscillating track. Ohrt et al. in U.S. Pat. No. 7,942,787 shows several adaptive motion rear drive exercise apparatus.
It is an objective of this invention to provide an exercise apparatus having varying stride lengths determined by the movement of an operator with a default mode for easy starting. A further objective is an exercise apparatus having varying stride lengths where the pedals follow elliptical curves for short, medium and long stride lengths.
SUMMARY OF THE INVENTION
The present invention relates to the kinematic motion control of pedals which simulate walking and jogging during operation. More particularly, apparatus is provided that offers variable intensity exercise through a leg operated cyclic motion in which the pedal supporting each foot is guided through successive positions during the motion cycle while a load resistance acts upon the mechanism.
The pedals are guided through an oblong curve motion while pedal angles are controlled to vary about the horizontal during the pedal cycle. Arm exercise is by handles coordinated with the mechanism guiding the foot pedals. The range of handle movement generally determines the pedal stride length.
In the original embodiment, the apparatus includes a separate pedal for each foot attached to a foot support member. A pair of crank arms rotate about a pivot axis positioned on the framework. A pair of support links are pivotally connected intermediate the ends to the crank arms and to foot support members. A pair of tracks are supported by the framework where a track actuator can change the incline. A pair of rollers are each rotatably attached to a respective foot support member and maintain rollable contact with a respective track. A pair of handles are attached to handle supports which are pivotally connected to the framework. A pair of connector links are pivotally connected to the handle supports and to one end of the support links. A cross member is pivotally connected to the framework. A pair of crossing links are pivotally connected to the cross member and to each handle support. The crossover member and crossing links form a crossover assembly to cause one handle to move forward while the other handle moves rearward.
The stride length of the pedal is generally determined by the range of movement of the handles. The shortest stride length occurs with no movement of the handles while the longest stride length of the pedals occurs with the longest range of movement of the handles. An even shorter stride is possible using only the feet to determine stride length with the hands of the user positioned upon the framework.
Load resistance is applied to the crank in this embodiment by a pulley which drives a belt to a smaller pulley attached to a flywheel supported by the framework. A tension belt covers the circumference of the flywheel to provide friction for load resistance on the intensity of exercise. A control system can adjust the tension on the tension belt through a load actuator to vary the intensity of exercise. It should be understood that other forms of load resistance such as magnetic, alternator, air fan or others may be applied to the crank. The control system also can adjust the incline of the tracks with the track actuator during operation to further change the intensity of exercise.
In the preferred embodiment, the apparatus includes a separate pedal for each foot attached to a foot support member. A pair of crank arms rotate about a pivot axis positioned on the framework forward an operator at generally pedal height. A pair of drive links are attached to the crank arms. Drive support links are pivotally connected to the drive links and the framework. A pair of support links are pivotally connected to the drive links and to the foot support members. A pair of rocker link guides are pivotally connected to the framework and to the foot support members. A pair of control links with handles attached are pivotally connected to the framework. A pair of connector links are pivotally connected to the control links and to the support links. A cross member is pivotally connected to the framework. A pair of crossing links are pivotally connected to the cross member and to each control link. The crossover member and crossing links form a crossover assembly to cause one handle to move forward while the other handle moves rearward. Energy storage devices are connected to the control links and framework to establish a default position for the control links that is generally vertical.
The stride length of the pedal is related to the range of movement of the handle. The shortest stride length occurs with no movement of the handles in the default mode for easy starting while the longest stride length of the pedals occurs with the longest range of movement of the handles.
Load resistance is applied to the crank in this embodiment by a pulley which drives a belt to a smaller pulley attached to a flywheel supported by the framework. A tension belt covers the circumference of the flywheel to provide friction for load resistance on the intensity of exercise. An adjustment knob can adjust the tension-on the tension belt to vary the intensity of exercise. It should be understood that other forms of load resistance such as magnetic, alternator, air fan or others may be applied to the crank.
In an alternate embodiment, the rocker link guides are replaced with roller and track guides wherein the rollers are pivotally connected to the foot support members and the tracks are attached to the frame. The remainder of this embodiment is essentially the same as the alternate embodiment. Operation is the same as the preferred embodiment. Easy starting occurs in the default mode with the handles held stationary as the pedals follow a short elongate curve. The longer handle range followed by the movement of the operator, the longer the stride length becomes.
In summary, this invention provides varying elliptical stride lengths as determined by the movement of an operator. The pedals move through elongate curves that simulate walking and jogging with very low joint impact. Arm exercise has a variable range of motion coordinated with the pedal movements. Pedal curves remain generally elliptical in shape throughout the range of variation. Easy starting occurs in the default mode.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a left side elevation view of the original embodiment;
FIG. 2 is the rear view of the original embodiment shown in FIG. 1 ;
FIG. 3 is a left side elevation view of the preferred embodiment of an exercise machine constructed in accordance with the present invention;
FIG. 4 is the front view of the preferred embodiment shown in FIG. 3 ;
FIG. 5 is a left side elevation view of an alternate embodiment.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Referring to the drawings in detail, pedals 46 and 48 are shown in FIGS. 1 and 2 in forward and rearward positions of the preferred embodiment. Crank arms 4 , 6 rotate about pivot axis 7 on framework 70 . Foot support members 14 , 16 have pedals 46 , 48 attached. Support links 8 , 10 are connected intermediate the ends to crank arms 4 , 6 at pivots 9 , 11 and to foot support members 14 , 16 at pivots 13 , 15 . Tracks 90 , 94 are attached to frame members 74 at pivot 93 and to track actuator 96 which is also attached to framework 74 . Rollers 40 , 44 are connected to foot support members 14 , 16 at pivots 41 , 43 and are in rollable contact with tracks 90 , 94 .
Handles 36 , 38 are attached to handle supports 80 , 84 which are connected to framework 70 at pivot 39 . Connector links 30 , 34 are connected to handle supports 80 , 84 at pivots 35 , 37 and to one end of support links 8 , 10 at pivots 31 , 33 . Crossover member 56 is connected to framework 70 at pivot 55 . Crossing links 50 , 54 are connected to crossover member 56 at pivots 53 , 59 and to handle supports 80 , 84 at pivots 51 , 57 . Crossover member 56 and crossing links 50 , 54 form a crossover assembly as shown in FIGS. 1 and 2 that cause handle 36 to move forward when handle 38 moves rearward.
Load resistance is imposed upon cranks 4 , 6 by pulley 49 which drives flywheel 63 by belt 69 coupled to pulley 71 which is supported by the framework 70 at shaft 61 . Tension belt 64 encompasses flywheel 63 with load actuator 66 connected for adjustment to vary the intensity of exercise on the exercise apparatus. Control system 68 is connected to load actuator 66 and track actuator 96 with wires 67 , 65 , 95 using conventional means not shown. Control system 68 can be programmed to adjust tension belt 64 using load actuator 66 or to change the incline of tracks 90 , 94 using track actuator 96 to vary the intensity of exercise during operation. Framework 70 is attached to longitudinal frame members 74 which are attached to cross members 73 , 75 that are supported by a generally horizontal surface.
Operation begins when an operator places the feet upon the pedals 46 , 48 in the default side by side position of pedals 46 , 48 . Moving the handles 36 , 38 and applying body weight to pedals 46 , 48 starts the crank arms 4 , 6 moving with ease. Holding handles 36 , 38 generally still as denoted by handle position 1 ′, pedals 46 , 48 move through a relatively short pedal curve 1 shown in FIG. 1 . Allowing the handles 36 , 38 to move through handle range 3 ′ causes pedals 46 , 48 to move along pedal curve 3 . Allowing handles 36 , 38 to move through handle range 5 ′ results in pedal curve 5 . Even shorter pedal curves are possible when the user is not grasping the handles whereby only the feet of the user define the motion.
In the preferred embodiment, pedals 46 and 48 are shown in FIGS. 3 and 4 in forward and rearward positions. Crank arms 4 , 6 rotate about pivot axis 7 positioned forward of an operator at generally pedal height on framework 70 . Foot support members 14 , 16 have pedals 46 , 48 attached at the ends. Drive links 20 , 22 are connected to crank arms 4 , 6 at pivots 9 , 11 . Drive link supports 86 , 88 are connected to drive links 20 , 22 at pivots 77 , 79 and to framework 70 at pivot 87 . Support links 8 , 10 are connected to drive links 20 , 22 at pivots 21 , 23 and to foot support members 14 , 16 at pivots 13 , 15 . Guides 26 , 28 are connected to framework 70 at pivot 17 and to foot support members 14 , 16 at pivots 25 , 27 . For this embodiment, guides 26 , 28 are further described as rocker links 26 , 28 .
Handles 36 , 38 are attached to control links 80 , 84 which are connected to framework 70 at pivot 39 . Connector links 30 , 34 are connected to control links 80 , 84 at pivots 35 , 37 and to support links 8 , 10 at pivots 31 , 33 . Crossover member 56 is connected to framework 70 at pivot 55 . Crossing links 50 , 54 are connected to crossover member 56 at pivots 53 , 59 and to control links 80 , 84 at pivots 51 , 57 . Crossover member 56 and crossing links 50 , 54 form a crossover assembly as shown in FIGS. 3 and 4 that cause control link 80 to move forward when control link 84 moves rearward.
Energy storage devices 60 , 62 are shown in FIGS. 3 and 4 as springs 60 , 62 connected to control links 80 , 84 at pivots 83 , 85 and to framework 70 at pivot 47 . Springs 60 , 62 are intended to cause control links 80 , 84 to have a bias towards the default vertical position where the shortest stride occurs at elongate curve 1 .
Load resistance is imposed upon cranks 4 , 6 by pulley 49 which drives flywheel 63 by belt 69 and pulley 71 . Flywheel 63 is supported by framework 70 at pivot 61 . Tension belt 64 encompasses flywheel 63 for adjustable load resistance using adjustment knob 91 to vary the intensity of exercise on the exercise apparatus. Framework 70 is attached to longitudinal frame members 74 and to cross members 73 , 75 that are supported by a generally horizontal surface.
Operation begins when an operator places the feet upon the pedals 46 , 48 in the default side by side position of pedals 46 , 48 . In the default mode, control links 80 , 84 are caused to be generally vertical in a side by side position by springs 60 , 62 . Other forms of energy storage devices 60 , 62 may also be used. In the default mode, pedals 46 , 48 will follow the shortest stride length along default elongate curve 1 . Startup is easy along the default elongate curve 1 . Handles 36 , 38 remain generally stationary at position 1 ′ while pedals 46 , 48 follow elongate curve 1 . When handles 36 , 38 move through handle range 3 ′, pedals 46 , 48 move along pedal curve 3 . When handles 36 , 38 move through an even greater handle range 5 ′, pedals 46 , 48 follow pedal curve 5 . The maximum stride occurs when pedals 46 , 48 follow pedal curve 2 while handles 36 , 38 have the handle range 2 ′.
An alternate embodiment is shown in FIG. 5 which is essentially the same as the alternate embodiment shown in FIGS. 3 and 4 except that guides 26 , 28 have been replaced with rollers 40 , 44 and tracks 90 serving as guides. Tracks 90 are attached to framework 70 and 74 at a predetermined angle. However, as shown in FIGS. 1 and 2 tracks 90 can be configured to have adjustable angles. Rollers 40 , 44 are connected to the foot support members 14 , 16 at pivots 41 , 43 . The remainder of this alternate embodiment is essentially the same as the preferred embodiment of FIGS. 3 and 4 . Operation is the same as the preferred embodiment where only pedal curves 2 and 5 are being shown in FIG. 5 .
In summary, the present invention has distinct advantages over prior art because the elliptical stride movement of the pedals 46 , 48 change with the range of movement 1 ′, 3 ′, 5 ′, 2 ′ of the handles 36 , 38 while maintaining a generally elliptical pedal curves 1 , 3 , 5 , 2 even for the longest pedal stride. Easy starting occurs in the default mode.
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the claims, rather than by foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. | The present invention relates to a standup exercise apparatus that simulates walking and jogging with arm exercise. More particularly, the present invention relates to an exercise machine having separately supported pedals for the feet and arm exercise coordinated with the motion of the feet where the pedal stride length is determined by the movements of an operator. Crank arms are positioned on the framework forward the operator at a height comparable to the pedals. Easy starting occurs in the default mode. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims benefit of the filing of U.S. provisional application 61/155,591 filed Feb. 26, 2009 and of UK application GB 0903227.
The sequence listing electronically filed herewith is hereby incorporates by reference in its entirety (File Name: 4091-55004Seq_ListCorrected3.txt; File Size: 18 KB; Date Created May 15, 2012).
FIELD OF THE INVENTION
The present invention relates to recombinant proteins. In particular, the present invention relates to proteins having fructanase activity and a method for their production.
INTRODUCTION
Fructans or fructooligosaccharides (FOS) are sugar polymers containing fructose molecules as well as fructose-glucose disaccharides. Fructans contain a core sucrose group (fructose and glucose) and an extension using fructose. Chemical bonds linking fructose and glucose differ from chemical bonds linking fructose to fructose. Fructans are often found in plants and play an important role in food industry and in probiotics or prebiotics (Prebiotics are carbon source for good bacteria. Humans can not metabolize these prebiotics). Examples of fructans are inulin or levan, both of which are fructose containing linear polysaccharides. Recent development indicates that fructans may also be used for the production of bio fuels, such as but not limited to bio-ethanol.
The production of bio-ethanol as well as many other processes utilising fructan as a carbon source for growth requires the hydrolysis of fructans in order to obtain monosaccharides such as fructose or glucose. The hydrolysis of fructans may be performed by naturally occurring enzymes such as a β-fructosidase precursor (fosE) as suggested in Goh et al., (“Functional Analysis of the Fructooligosaccharide Utilization Operon in Lactobacillus paracasei 1195”; Applied and Environmental Microbiology, September 2007, p. 5716-5724). Extracellular enzymes such as inulinase that hydrolyse fructans are extracted from Aspergillus niger and are commercially available. These extracellular enzymes are naturally occurring enzymes that are isolated or extracted from their natural environments. However, these fructanase extracellular enzymes are expensive and difficult to obtain in sufficient amounts and good purity for large scale applications.
SUMMARY OF THE INVENTION
The present invention relates to a novel protein and a method for the manufacture thereof. The novel protein according to the invention is a recombinant protein with fructanase activity. The recombinant protein according to the invention is an engineered protein derived from recombinant DNA encoding for the protein. The recombinant protein may be or may comprise a fragment of a naturally occurring protein, i.e. of a naturally occurring fructanase protein. The recombinant protein may be an enzyme. The fragment may have an amino acid sequence corresponding essentially to Seq. ID 3 or a homologue or variant thereof or may be a similar related sequence.
The fructanase activity of the recombinant protein may have advantageous properties for production and hydrolysis of fructans. The recombinant protein may hydrolyse at least one type of fructan to obtain sugar molecules. The fructose may be D-fructose and the glucose in fructan may be D-glucose. The protein may thus be termed fructanase. The protein may also be a levanase, and in this case the protein will hydrolyse levans, or an inulinase where the protein will hydrolyse inulin. Other polysaccharides may also serve as substrates.
Examples of fructans are inulin, levan, 1-kestose, nystose, raffinose, stachyose and melezitose or a combination thereof.
The recombinant protein may be a peptide. The protein may have a molecular weight of less than about 140 kDa. The protein may have a molecular weight of less than about 100 kDa. As a non-limiting an example, the protein may have a molecular weight of about 81.1 kDa.
The recombinant protein may comprise a portion of the amino acid sequence of a β-fructosidase precursor (fosE). The fosE may be fosE of lactic acid bacteri such as Lactobacillus, Leuconostoc, Pediococcus, Lactococcus , and Streptococcus or the like. For example Lactobacillus paracasei, Lactobacillus casei, Lactobacillus rhamnosus or others may be used. The recombinant protein may also be from another organism e.g. prokaryote or eukaryote.
The portion or fraction may be a domain or a core domain of fosE. The portion may be an amino acid sequence encoding for a certain region of fosE. However, modification may be made to this portion in a usual manner. Further amino acids or an amino acid sequence may be added to the portion or certain amino acids may be removed or replaced in a usual manner well known in the art. For example, the portion may have a modified N-terminal and a modified C-terminal amino acid sequence.
The protein may comprises one or more tags. For example, the tags may be used for purification. One or more hisitidine residues may be added to form one or more polyhistidine tags (his-tags). For example, a his-tag may be added at the C-terminal side of the portion. Other tags known in the art may also be used for the purification of the protein.
An expression vector, such as pET17b or other vectors known in the art may be attached to a DNA sequence encoding the protein to enable production in an appropriate host.
The protein of the invention may be used in the fermentation of fructans and to produce monosaccharides from fructans as, for example, a step in the production of ethanol from fructans. Other uses may be in processing of fructans to release fructose.
The invention also relates to DNA encoding for the recombinant protein. The invention further related to an expression system or expression construct for expressing the recombinant protein. The recombinant protein may be expressed in prokaryotic or eukaryotic cells, for example in Escherichia. coli ( E. coli ).
A preferred method for delivering the expression construct into the cell is transformation or transfection, wherein known substances for alleviating transfer of the expression construct through the cell membrane are within the scope of the present invention.
Genetic material comprising nucleic acids, polynucleotides, RNA and DNA, of either natural or synthetic origin, including recombinant RNA and DNA and antisense RNA and DNA; hammerhead RNA, ribozymes, antigene nucleic acids, both single and double stranded RNA and DNA and analogs thereof, either in combination or not with other elements such as, for example, without limitation, cell specific enhancers, and nuclear localization signals, can be introduced into prokaryotic or eukaryotic cells or organisms via transformation or transfection techniques. The present invention uses an “expression construct”, “nucleic acid construct” or alternatively a “nucleotide construct” or alternatively a “DNA construct”. The term “construct” is used herein to describe a molecule, such as a polynucleotide may optionally be chemically bonded to one or more additional molecular moieties, such as a vector, or parts of a vector. In a specific—but non-limiting—aspect, a nucleotide construct is exemplified by a DNA expression constructs suitable for the transformation of a cardiac host cell. As used herein, the terms “transformation” and “transfection” are intended to refer to a variety of art-recognized techniques for introducing foreign nucleic acid into a host cell/or tissue, including, for example, without limitation, calcium phosphate or calcium chloride co-precipitation, DEAE-dextran-mediated transfection, lipofection, or electroporation. Suitable methods for transforming or transfecting host cells can be found in Sambrook, et al. (supra), and other laboratory manuals.
The invention further relates to a method for the manufacture of a recombinant protein with fuctanase activity, the method comprising: expressing a protein with fructanase activity in an expression system; isolating the protein with fructanase activity, wherein the protein is a recombinant protein that comprises a fragment or a partial sequence of a naturally occurring protein. The protein may be a protein as set out above, i.e the naturally occurring protein may be a naturally occurring fructanase protein. The recombinant protein may be an enzyme. The fragment may have an amino acid sequence corresponding essentially to Seq. ID 3 or a homologue or variant thereof or may be a similar related sequence.
Expressing the protein may be performed using prokaryotic cells such as bacteria, (i.e. Escherichia. coli ( E. coli )). Other expression systems known to a person skilled in the art may also be used.
The isolated protein may be purified for example using a histidine-tag (his-tag) or other tags known in the art. The his-tag may be attached at the C-terminal of the protein.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A shows a SDS-PAGE of purified recombinant truncated β-fructosidase precursor (ΔfosE).
FIG. 1B shows an indication of the partial polypeptide sequence of ΔfosE expressed in E. coli compared to the native β-fructosidase precursor (fosE) protein's amino acid sequence (not underlined portion).
FIG. 2 shows temperature (A) and pH (B) profiles for activity of the recombinant ΔfosE activity using chicory inulin as a substrate.
FIG. 3 shows activity profiles using different carbon sources and activity of a recombinant ΔfosE protein.
FIG. 4 illustrates the growth of yeast on grass juice and in the presence of recombinant ΔfosE and when heat denatured.
FIG. 5 . shows measurements of a) ethanol yield, b) optical density and c) cell numbers estimated by haemocytometer counts for Saccharomyces cerevisiae grown on untreated grass juice (GJ), GJ+recombinant ΔfosE, GJ+ hd recombinant ΔfosE, GJ+Exo-Inulinase, GJ+Endo-Inulinase and GJ+Exo/Endo-Inulinase (t 75 hr). *=significantly higher (Student's t-test, P<0.05, n=3) values than those seen on untreated GJ.
DETAILED DESCRIPTION
The following description of an embodiment of the invention is purely exemplary and the invention is by no means limited to this embodiment. A person skilled in the art will easily adapt the teachings to other biological systems.
The invention is demonstrated by the example of a truncated polypeptide cloned from the β-fructosidase precursor (fosE) from Lactobacillus paracasei ( L. paracasei ). It is evident to a person skilled in the art that the invention may be applied to fosE of other Lactobacillus species or other lactic acid bacteria as well as to other natural occurring proteins having fructanase activity.
The truncated polypeptide comprises the N-terminal deletion of signal sequences and the C-terminal deletion of cell-binding motif found in the native protein of L. paracasei . The truncated polypeptide was expressed successfully in Escherichia. coli ( E. coli ) using pET17b as expression vector and forming a ΔfosE-pET17b construct. Polymerase chain reaction using pfx polymerase was utilised to isolate the open-reading from strain 4134. The N-terminal amino acid sequence MAS comprised part of the NheI restriction site and ATG start triplet. A polyhistidine tag (his-tag) to facilitate purification, a stop codon and a BamHI restriction site were encoded in the primer for PCR corresponding to the C-terminal amino acid sequence.
Primers utilized in this work, referred to as Seq. ID 1 and Seq. ID 2:
(Seq.ID 1)
5′ ACGTAGCTAGCGCTACAAGTGCTTCGTCTAC
(Seq.ID 2)
5′ CGTAGGATCCTCAGTGGTGGTGGTGGTGGTGTTTTTCAGTTAGTTGA
CCAG
The truncated polypeptide comprises a portion of the amino acid sequence of fosE of L. paracasei . The amino acid sequence portion may be termed core domain of the β-fructosidase precursor (ΔfosE) having the amino acid sequence in, which is referred to as Seq. ID 3):
MAS ASSASSTQISQTNTGSQPNNETTGETAQSSVNSTATASSSSVADLPSSSDSKSSIGSTISQPTVDK KETSKSDTADNDLTKSVTTSDSDKALPTSKTTLPTSNEQVQSSVGQSQTDQPASSATIATNAVTSDVS QNDQYNEPYRNQYHYSSSQNWINDPNGLFYDSKTGLYNLYYQYNPEGNQWGNMSWGHAVSKDLI NWTQEDVAIPMLQNQGWEDFTYTNTTGSLKDKGEVRYVGVPTTNWGDADGKKAIFSGSIVVDTN NVSGLGKDAILAFYTADYQIATRKNDGAEDGWGTWIGLTEIQEQHLAYSLDGGKTFIQYSKDGNAA NPQAIIPTSMNQGGDAANFRDPSVVYDAVNKQYYLTVVSGQQALIYKSSNLLDWTYASKIERENDV GNGVWECPSLVPMKVAGTNETKWVFCISVQQGAHATGSGMQYYVGNMTADGTWVPESSKTLQN PMTMDSGEDFYAGIPFSNMPDGRTVMLAWQSNWSYVDEAKTSPWSGNMTLPRELSLKKNADTTD GYLLTNTVVKEIANNEEANVINKAESNFTVSRSDEQVQYEGKQYKISATFSWDEADKPKSVGFKLR VSDDQKYDMIVGYDLTTGLLYVQRLNTGEPNMGAPRDKMNATVNADGSITITVYVDETSIEAFAN DGEKSITQNFFMRPENIGDQATTGVYVYSNDGTTKISDLTINPITSIWNSTGQLTEK
An N-terminal amino acid sequence MAS has been added.
This is compared to the amino acid sequence of fosE of L. paracasei , referred to as Seq. ID 4:
>Q27J21|Q27J21_LACPA Beta-fructosidase -
Lactobacillus paracasei .
MEMDEKKHYKMYKSKSVWVFACLSTCLIVSFFNDGQNVSAATSASSTQISQTNTGSQPNN
ETTGETAQSSVNSTATASSSSVADLPSSSDSKSSIGSTISQPTVDKKETSKSDTADNDLT
KSVTTSDSDKALPTSKTTLPTSNEQVQSSVGQSQTDQSASSATIATNAVTSDVSQNDQYN
EPYRNQYHYSSSQNWINDPNGLFYDSKTGLYNLYYQYNPEGNQWGNMSWGHAVSKDLINW
TQEDVAIPMLQNQGWEDFTYTNTTGSLKDKGEVRYVGVPTTNWGDADGKKAIFSGSIVVD
TNNVSGLGKDAILAFYTADYQIATRKNDGAEDGWGTWIGLTEIQEQHLAYSLDGGKTFIQ
YSKDGNAANPQAIIPTSMNQGGDAANFRDPSVVYDAVNKQYYLTVVSGQQALIYKSSNLL
DWTYASKIERENDVGNGVWECPSLVPMKVAGTNETKWVFCISVQQGAHATGSGMQYYVGN
MTADGTWVPESSKTLQNPMTMDSGEDFYAGIPFSNMPDGRTVMLAWQSNWSYVDEAKTSP
WSGNMTLPRELSLKKNADTTDGYLLTNTVVKEIANNEEANVINKAESNFTVSRSDEQVQY
EGKQYKISATFSWDEADKPKSVGFKLRVSDDQKYDMIVGYDLTTGLLYVQRLNTGEPNMG
APRDKMNATVNADGSITITVYVDETSIEAFANDGEKSITQNFFMRPENIGDQATTGVYVY
SNDGTTKISDLTINPITSIWNSTGQLTEKFVDENGNTIASDKIQTGRVGQSYTSESATIP
GYVFVKENTDHINSNQLYTTQNQTITYTYRASQASVVTKDTTLAAGPSAAWNAADNLVGA
TDADGNALAVSDLTVNGAVDPKTPGTYTVTYSYTDATGNKISKKATVTVIASKADIVTKD
TTMVAGASTIWNAADNFVEAKNADGNALTVSDLMINGTVDSKTPGTYTVTYSYTDAAGNK
INKEAIVTVIASKADIVTKDTTMVAGPSAAWNAVDNFVEATGADGNALALSDLTVNGAVD
PKTPGTYTVTYSYTDPAGNKISKEATVTVIASKADIVTKDTTMVAGPSATWNAVDNFVEA
TGADGNALALSDLTVNGAVDPKTPGTYTVTYSYTDVAGNKISKEAIVTVIASKADIVTKD
TTKVAGPSATWNAADNLVIATDAKGNALALSNLTVTGSVDSKTPGTYTVTYSYTDAAGNK
ISKEATVTVIASKADIVTKDTTMVAGPSAAWNAANNLVSATDADGNALAMSNLTVTGTVD
LKTQGTYTVTYTYTDVAGNKISKEATVTVLTEKETNIEDNTGSSISNDRENPPASITGKG
GDDIHQNAKTTMTKKKTETLPQAGNHVNELAIVLGQMILAICVGGILWLKRRVKRV
A direct comparison of ΔfosE sequence and fosE sequence is shown in FIG. 1B . The complete sequence corresponds to the sequence of fosE while the sequences left away for ΔfosE are underlined. Consequently, the non-underlined portion corresponds to the ΔfosE protein sequence.
The ΔfosE sequence is expressed in bacterial system and the recombinant ΔfosE protein is isolated and eventually purified as described below. The obtained ΔfosE protein is en enzyme having fructanase activity, i.e. the ΔfosE protein is a levanase or an inulinase or both, hydrolysing levan and inulin and other fructans.
Heterologous Expression in E. Coli and Isolation of Recombinant ΔfosE protein.
The ΔfosE-pET17b construct was transformed into E. coli strain BL21 (DE3) and positive transformants selected using ampicillin. Overnight cultures (10 ml) of transformants were used to inoculate one litre volumes of Terrific Broth supplemented with 20 g·l −1 peptone and 0.1 mg·ml −1 sodium ampicillin. Cultures were grown at 37° C., 230 rpm for 7 hours prior to induction with 1 mM IPTG and expression at 30° C., 190 rpm for 18 hours. Recombinant ΔfosE protein was isolated according to the method of Arase et al (Arase M, Waterman M R, Kagawa N; Biochem Biophys Res Commun 2006 May 26; 344(1):400-5. Epub 2006 Mar. 20) except that 2% (w/v) sodium cholate and no Tween20 were used in the sonication buffer. The solubilized ΔfosE protein was purified by affinity chromatography using Ni 2+ -NTA agarose with the modification that 0.1% (w/v) L-histidine in 50 mM sodium phosphate, pH 7.5, 25% (w/v) glycerol was used to elute non-specifically bound E. coli proteins after the salt washes and elution of P450 protein was achieved with 1% (w/v) L-histidine in 50 mM sodium phosphate, pH 7.5, 25% (w/v) glycerol. Isolated ΔfosE protein fractions were stored at −80° C. Protein purity was assessed by SDS polyacrylamide gel electrophoresis and the identity of the purified protein confirmed by trypsin digestion followed by nano-LC/MS/MS of the tryptic peptides released. A SDS page of purified recombinant ΔfosE is illustrated in FIG. 1A .
Determination of Fructanase Activity.
Fructanase activity, in this example exo-fructanase activity, was determined using a discontinuous assay system with the levels of fructose produced being determined at fixed time intervals. The standard assay system consisted of a 1 ml reaction volume of saccharide solution in 0.1 M sodium acetate, pH 5, containing 1.62 ng/ml Ni-NTA agarose purified ΔfosE. Incubation was for 30 minutes at 37° C. prior to the withdrawal of 100 μl for colour development with 0.9 ml of 1 mg/ml 2,3,5-triphenyl tetrazolium chloride in 1 M NaOH (15 minutes at 37° C.). The pink-red colour produced was monitored by the absorbance at 520 nm. The colorimetric assay was standardised against 100 μl of fructose solutions (0 to 6 mM) in 0.1 M sodium acetate, pH 5. Each assay was performed in triplicate. The colorimetric reaction with 2,3,5-triphenyl tetrazolium chloride was found to be 20-fold more sensitive for D-fructose than D-glucose using the conditions described above. Exo-fructanase activity was expressed as nmoles of fructose produced per minute per μg ΔfosE protein.
Protein concentrations were determined by the Coomassie Blue 8250 dye-binding method (BioRad, Hemel Hempstead, UK) using bovine serum albumin standards. Spectral determinations were made using a Hitachi U-3310 UV/VIS spectrophotometer (San Jose, Calif.).
Thermostability Determinations.
Stock solutions (162 μg/ml) of Ni-NTA agarose purified ΔfosE protein were incubated for ten minutes at temperatures ranging from 22 to 90° C. These enzyme solutions were then incubated on ice prior to the commencement of the exo-fructanase assay described above in 10% (w/v) chicory inulin, 0.1 M sodium acetate, pH 5. The inulin was solubilised by warming to 70° C. for 5 minutes followed by cooling to room temperature prior to use.
pH-Profile Determinations.
The pH-profile of ΔfosE protein was determined between pH 3 and 11 using 10% (w/v) chicory inulin dissolved in 0.1 M buffer as described previously. The buffers used were 0.1 M sodium acetate (pHs 3, 3.5, 4, 4.5, 5, 5.5, 6), 0.1 M sodium phosphate (pHs 6.5, 7, 7.5), 0.1 M Tris-HCl (pHs 8, 8.5) and sodium bicarbonate/carbonate (pHs 9, 9.5, 10, 10.5, 11).
Substrate Saturation Determinations.
Substrate specificity for ΔfosE protein was determined using chicory inulin (0.125 to 20% w/v), sucrose (0.025 to 2 M), 1-kestose (0.005 to 0.4 M), nystose (0.0045 to 0.35 M), rafinose (0.02 to 0.48 M), levan (from Zymomonas mobilis 0.088 to 3.5% w/v), stachyose (0.04 to 0.4 M) and melezitose (0.04 to 0.4 M) in 0.1 M sodium acetate, pH 5 using the exo-fructanase assay system described previously.
Chemicals.
All chemicals, unless otherwise stated, were obtained from Sigma Chemical Company (Poole, UK). DIFCO growth media were obtained from Becton Dickinson Ltd (Cowley, UK).
Experimental Results
Heterologous Expression and Purification of Recombinant ΔfosE Protein.
Expression of truncated fosE levanase (recombinant ΔfosE protein) in E. coli followed by purification using affinity chromatography on Ni-NTA agarose yielded 22.5 nmoles fosE levanase from 1 litre of cell culture which was over 95% pure as resolved by SDS-PAGE (lane 3— FIG. 1A ). However, only 35% of the total exo-fructanase activity (as determined using 10% w/v chicory inulin) detected in the cytosolic fraction was recovered, albeit with a 5-fold increased in specific activity. Less than 1% of the exo-fructanase activity was found not to bind to the Ni-NTA agarose matrix. SDS-PAGE ( FIG. 1A ) indicated that the recombinant ΔfosE protein had an apparent molecular weight of 100 kDa, some 20 kDa greater than that predicted from the amino acid sequence of the truncated fosE enzyme. The identity of the purified ΔfosE protein was confirmed by trypsin digestion of the 100 kDa SDS-PAGE band (FIG. 1 A—lane 3) followed by nano-LC/MS/MS, identifying 21 peptides present in ΔfosE protein (Q27J21—full length sequence) which accounted for 50.7% coverage of the truncated protein ( FIG. 1B ) with a MASCOT score of 3609. Gel exclusion chromatography of ΔfosE protein on Sephacryl S-400HR indicated that the native molecular weight of the ΔfosE protein was 85 kDa (data not shown) when compared against several protein standards ranging in molecular weight from 12 to 700 kDa. While the polypeptide used in the invention had a predicted molecular weight of 81.1 kDa the predicted molecular weight of the native protein is 147 kDa.
Biochemical Characterisation of ΔfosE Protein.
Thermostability studies ( FIG. 2A ) indicate that the recombinant ΔfosE protein was stable up to 46° C. for 10 minutes. At temperatures higher than this, the fructanase activity is rapidly lost, with the ΔfosE protein effectively deactivated by temperatures higher than 55° C. The T 0.5 value for the ΔfosE protein was calculated to be 49° C. under the stated conditions. The pH profile ( FIG. 2B ) of the ΔfosE protein, using 10% (w/v) chicory inulin, indicated an optimal pH of 5 to 5.5 for the exo-fructanase activity measured, with the activity of the ΔfosE protein falling sharply as the pH fell below 5.0. The decrease in the observed exo-fructanase activity as the pH is increased above 5.0 is gradual, with the ΔfosE protein effectively becoming inactive at pH values above 8.
Substrate saturation experiments with the polyfructans chicory inulin and especially bacterial levan ( FIG. 3A ) were hampered by the relative insolubility of these compounds in 0.1 M sodium acetate buffer, pH 5. This relative insolubility was partially solved by warming the solutions for 5 minutes at 70° C., which increased the solubility of these the compounds, even when cooled back to room temperature. However, incubation for periods longer than 5 minutes at 70° C. were avoided at this caused the release of free fructose from the polyfructans (probably by acidic hydrolysis of the glycosidic bonds). The bacterial levan became extremely viscous at concentrations 3.5% (w/v) preventing higher concentrations from being used. The chicory inulin solutions above 6% (w/v) became progressively more viscous with the chicory inulin solution progressively changing in appearance from a colourless solution to a viscous white slurry at 25% (w/v). A saturating concentration of bacterial levan could not be obtained due to solubility problems of the bacterial levan, with 3.5% (w/v) levan yielding an exo-fructanase specific velocity of 66 nmol/min/μg. A saturating concentration of 8% (w/v) chicory inulin (78 nmol/min/μg) was obtained above which, the observed enzyme velocity fell with further increase in the chicory inulin concentration. This is indicative of substrate inhibition and k m and k i values for chicory inulin of 7.8% and 11.2%, respectively, were calculated by non-linear regression of the Michaelis-Menten single substrate inhibition equation [v=(V max ·[S])/(k m +([S] 2 /k i )+[S])]. The inhibition caused by chicory inulin concentrations above 8% (w/v) is likely to be due in part to viscosity effects rather than ‘classical’ substrate inhibition alone.
Substrate saturation experiments with the oligosaccharides ( FIG. 3B ) 1-kestose, nystose, rafinose, stachyose and melezitose were less problematic, with no solubility problems encountered up to 0.5 M. The stachyose and the melezitose could not be hydrolysed to produce free fructose by the ΔfosE protein under the stated exo-fructanase assay conditions at concentrations up to 0.5 M saccharide. The rafinose was a relatively poor substrate with a specific velocity of just 2 nmol/min/μg observed in 0.32 M rafinose. This was is in contrast to both the 1-kestose and the nystose. The nystose gave a ‘biphasic’ substrate saturation curve with the first Michaelis-Menten phase extending up to 0.2 M, yielding a specific velocity of 39 nmol/min/μg and a k m value of 15.5 mM. At higher nystose concentrations, the velocity significantly increases well beyond what is predicted by either the Michaelis-Menten or Hill equations. The substrate saturation curve obtained with the 1-kestose achieved a maximum velocity of 47 nmol/min/μg at 0.1 M kestose, with further increases in kestose concentration causing a progressive reduction in the observed exo-fructanase velocity. This velocity curve is indicative of substrate inhibition and can be described using the Michaelis-Menten single substrate inhibition equation (see above) with k m and k i values of 50 mM and 210 mM, respectively, being obtained for 1-kestose.
The substrate saturation velocity curve obtained with sucrose ( FIG. 3C ) obeyed Michaelis-Menten kinetics yielding a k m value of 398 mM and an observed specific velocity of 62 nmol/min/μg with 2 M sucrose. The ability to hydrolyse sucrose into free fructose and glucose is indicative of an invertase/sucrase enzyme. Therefore, the ΔfosE protein exhibits wide-ranging substrate specificity for the exo-fructanase reaction, suggesting that this ΔfosE protein could be a levan(o)sucrase rather than a typical exo-fructanase/levanase/inulinase.
Table 1 shows further characterisation of the ΔfosE protein for the release of fructose from the fructan in grass juice with potential for the optimised production of bioethanol from grass. The table 1 shows efficient release of fructose in column 2 that is abolished on addition of heat denatured protein in column 3 The ΔfosE protein compares well with commercial endo- and exo-inulinase and a combination of these. The release of sugars fermentable by Saccharomyces cerevisiae as opposed to the fructan polymer could provide a route to optimal bioethanol production using the novel ΔfosE protein or derivatives thereof made by genetic improvements.
Carbohydrate content of growth and fermentation media (t 0 hr)
n.d = not determined
Δ = change (±) in glc or fru content following enzyme addition
Glucose concentrations quantified using a Glucose Assay Kit (GAGO-20, SIGMA).
Fructose concentrations quantified using a colorimetric assay for six-carbon ketohexoses (not glucose).
This is supported by the examination of growth characteristics in FIG. 4 which illustrates the growth of yeast on grass juice and in the presence of recombinant ΔfosE protein and when heat denatured. The presence of the active protein allows enhanced growth compared to a heat denatured form.
FIG. 5 shows measurements of a) ethanol yield, b) optical density and c) cell numbers estimated by haemocytometer counts for Saccharomyces cerevisiae grown on untreated grass juice (GJ), GJ+recombinant ΔfosE, GJ+ hd recombinant ΔfosE, GJ+Exo-Inulinase, GJ+Endo-Inulinase and GJ+Exo/Endo-Inulinase (t 75 hr). *=significantly higher (Student's t-test, P<0.05, n=3) values than those seen on untreated GJ. | The present invention relates to a novel protein and a method for the manufacture thereof. The novel protein according to the invention is a recombinant protein with fructanase activity. The recombinant protein according to the invention is an engineered protein derived from recombinant DNA encoding for the protein. The recombinant protein may be or may comprise a fragment of a naturally occurring protein, i.e. of a naturally occurring fructanase protein. | 8 |
[0001] The present invention relates to a yarn-feeding/recovering method for textile machines and to an apparatus for carrying out such method.
BACKGROUND OF THE INVENTION
[0002] In the textile field, weft feeders are known which are provided with a stationary drum on which a motorized swivel arm winds a plurality of yarn loops forming a stock. The yarn, which is unwound from the drum upon request of a textile machine arranged downstream, is subject to a stabilizing brake that maintains the unwinding yarn under a slight tension. The stabilizing brake typically comprises a frustoconical hollow member which is biased with its inner surface against the delivery edge of the drum by manually adjustable elastic means.
[0003] As described in EP 2031106, in order to maintain the feeding tension substantially constant, a controlled brake may be arranged downstream of the feeder, e.g., a foil-based brake of the type described in EP 0622485. This brake is controlled by a feedback loop which receives a measured tension signal from a sensor, then compares it with a reference tension which is indicative of a desired tension, and finally modulates the braking action in such a way as to minimize the difference between the reference tension and the measured tension.
[0004] Feeders are also known in which the yarn is wound on a rotary drum, which draws the yarn from a reel and feeds it to the downstream textile machine In this case, the tension of the yarn unwinding from the feeder is controlled by modulating the speed of rotation of the drum, always on the basis of a signal received from a tension sensor as in the previous case. Accordingly, in other words, the change of tension to be applied is determined by the difference between the yarn-feeding speed and the yarn-drawing speed set in the downstream machine
[0005] As known, certain particular processes, e.g., weaving the heel of socks, require that the yarn fed to the machine is periodically recovered and then returned. This operation is usually carried out by a dedicated recovering device arranged upstream of the machine.
[0006] A recovering device of this type is described in EP 1741817 and essentially comprises a motorized reel having an oblique passage defined therein, through which the yarn runs. The passage extends between an inlet port which is axially formed on an end surface of the reel, and an outlet port which is formed on the cylindrical, lateral surface of the reel. When an amount of yarn must be recovered, the downstream machine sends a signal to the recovering device which enables the rotation of the reel, so that the yarn is wound upon the reel.
[0007] As well known to the person skilled in the art, a critical issue of the above systems consists in coordinating the operation of the braking system, which operates on the basis of the measured tension of the yarn, with the operation of the recovering system, which is enabled in response to commands sent from the downstream machine on the basis on a predetermined pattern, with consequent difficulties in accurately controlling the feeding parameters and the state of the yarn during the recovering steps, e.g., in relation to possible, accidental events which may occur, such as a yarn breakage.
SUMMARY OF THE INVENTION
[0008] It is a main object of the present invention to provide a method in which the yarn-feeding function and the yarn-recovering function are coordinated with each other in a more reliable and more accured manner with respect to the prior art, particularly in relation to the control of the yarn tension during the recovering step and to the reaction in case of accidental events, such as a yarn breakage; it is also an object to provide an apparatus for carrying out such method.
[0009] The above objects and other advantages, which will better appear from the following description, are achieved by a method having the features recited in claim 1 , as well as by an apparatus having the features recited in claim 7 , while the dependent claims state other advantageous, though secondary features, of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The invention will be now described in more detail with reference to a few preferred, non-exclusive embodiments, shown by way of non limiting example in the attached drawings, wherein:
[0011] FIG. 1 diagrammatically shows an apparatus for carrying out the method according to the invention;
[0012] FIG. 2 is a side elevation view of a recovering device of a known type used in the apparatus of FIG. 1 ;
[0013] FIG. 3 is a view similar to FIG. 2 , which shows the recovering device in a different operative configuration;
[0014] FIG. 4 is a flowchart showing the steps of the method according to the invention;
[0015] FIG. 5 diagrammatically shows an apparatus for carrying out the method according to an alternative embodiment of the invention;
[0016] FIG. 6 is a perspective view of a yarn feeder with rotary drum, which is modified according to the invention to incorporate the apparatus of FIG. 5 ;
[0017] FIG. 7 is a front elevation view of the yarn feeder of FIG. 6 ;
[0018] FIG. 8 is a side elevation view of the yarn feeder of FIG. 6 ;
[0019] FIG. 9 is a broken away view similar to FIG. 8 , showing the yarn feeder sectioned along axis IX-IX of FIG. 7 ;
[0020] FIG. 10 is a front elevation, broken away view of the yarn feeder of FIG. 6 sectioned along axis X-X of FIG. 8 ;
[0021] FIG. 11 is a Figure similar to FIG. 7 , showing the yarn feeder to an enlarged scale and in a different operative configuration;
[0022] FIG. 12 is a flowchart showing the steps of the method according to the alternative embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] FIG. 1 diagrammatically shows a yarn-feeding/recovering apparatus 10 having a yarn feeder 12 provided with a stationary drum 14 and with a flywheel 16 driven to rotate by a motor 18 . The flywheel draws yarn F from a spool 20 and winds it on drum 14 in the shape of loops forming a stock.
[0024] Yarn F, which is unwound from the drum upon request of a general textile machine 22 arranged downstream, is subject to the braking action of a stabilizing brake adapted to maintain the yarn under a slight tension. The stabilizing brake conventionally comprises a frustoconical hollow member 24 which is biased with its inner surface against the delivery edge of drum 14 by elastic means 26 .
[0025] In a way known per se, yarn F coming out of stabilizing brake is further subject to the braking action of an electronic yarn-braking device (or brake) 28 which is controlled by a tension control block TC of a control unit CU (which is typically incorporated in yarn feeder 12 ). Control unit CU is programmed to modulate the braking action applied to yarn F by electronic brake 28 , on the basis of a signal received from a tension sensor 30 , in such a way as to maintain the tension of the delivered yarn substantially constant on a reference value T_ref.
[0026] The stock on drum 14 is controlled by a triad of sensors. A first sensor S 1 , preferably a Hall sensor, detects the passage of magnets M integral with flywheel 16 in order to determine the amount of yarn which is wound on the drum and the winding speed. A second sensor S 2 , preferably a mechanical sensor, provides a binary information about the presence of a minimum amount of yarn at an intermediate area of drum 14 . A third sensor S 3 , preferably an optical sensor, generates one pulse UWP per each loop unwound from the drum. A speed-evaluating block SE processes signals UWP in order to calculate the yarn comsumption speed on the basis of the time interval between pulses UWP, and generates an enabling signal LE which enables tension control block TC when this speed is higher than a predetermined threshold value, which is preferably equal to zero in the present embodiment. An apparatus of this type is described in EP 2031106, to which reference should be made for a more detailed description.
[0027] A yarn-recovering device 32 of the type described in EP 1741817 and shown in detail in FIGS. 2 , 3 , is arranged between electronic brake 28 and tension sensor 30 .
[0028] Yarn-recovering device 32 comprises a reel 34 keyed to a drive shaft 36 of a motor 38 , preferably a stepping motor or, alternatively, a brushless motor provided with an absolute sensor, in order to measure the real position based on techniques conventional in the field. Reel 34 is arranged with its axis A slanting at a first angle a with respect to the direction of yarn F, indicated by arrow D, so that its end surface 34 a facing away from motor 38 obliquely faces the incoming yarn. Reel 34 has an axial cylindrical seat 40 at its end surface 34 a. A passage 44 defined within reel 34 extends between an inlet port 44 a open to axial cylindrical seat 40 , and an outlet port 44 b open to the lateral, winding surface 34 b of the reel. Passage 44 is rectilinear and is slanting at a second angle b, which is substantially equal to first angle a, with respect to axis A of the reel. An internally rounded wearproof ring 46 made of ceramic is applied to the edge of cylindrical seat 40 . An inlet yarn-guide eyelet 48 and an outlet yarn-guide eyelet 50 respectively applied upstream and downstream of reel 34 are arranged at the same level of wearproof ring 46 .
[0029] Yarn F passes through upstream yarn-guide eyelet 48 , cylindrical seat 40 , passage 44 and downstream yarn-guide eyelet 50 . By operating motor 38 , as shown in FIG. 3 , the yarn downstream of the yarn-recovering device is wound on reel 34 . For a more detailed description of yarn-recovering device 32 , reference should be made to EP 1741817.
[0030] With the method according to the invention, as described in the flowchart of FIG. 4 , electronic brake 28 and yarn-recovering device 32 are alternately enabled as a function of the signals from third sensor S 3 , which are indicative of the yarn comsumption, independently from any other operative signals from downstream machine 22 .
[0031] In detail, as long as signal LE indicates that yarn is being unwound (LE=1), control unit CU continues to modulate the braking action of electronic brake 28 in such a way as to maintain the tension substantially constant at reference value T_ref, while yarn-recovering device remains at a position of minimum interference with the yarn, as shown in FIG. 2 . When signal LE indicates that yarn is no longer unwound from the drum (LE=0), which circumstance is indicative of the fact that the downstream machine has either stopped to draw yarn or started to return it, control unit CU “freezes” the braking action at the last value and, if measured tension T_meas is lower than a lower threshold tension T_lim_inf, than it enables yarn-recovering device 32 to recover yarn, while its speed V RR is continuously modulated in such a way as to maintain the tension substantially constant on reference value T_ref. At this stage, the number of revolutions and fractions of revolutions N completed by reel 34 is monitored.
[0032] It should be noted that, with the method according to the invention, reel 34 can rotate at a modulated speed in both directions. In fact, after an initial yarn-recovering step, during which the exceeding yarn is wound on reel 34 in order to maintain the tension at the desired level T_ref, the subsequent request of yarn from the downstream machine will cause reel 34 to rotate in the opposite direction always at a controlled speed, in order to return the yarn; however, before reaching the initial position (N=0) it could have to recover yarn again. When the reel reaches the initial position, control unit CU stops reel 34 , enables electronic brake 28 again, and then the cycle is repeated. As shown in the flowchart of FIG. 4 , two emergency conditions are provided, by which the tension control is bypassed while yarn-recovering device 32 is enabled. A first condition occurs when N reaches a value N_max corresponding to the maximum amount of yarn which can be stored on the reel. In this case, the process is stopped and an alarm signal is generated. The second condition occurs when signal LE indicates that yarn is unwinding from the feeder; this means that the downstream machine is drawing yarn at a speed such that the yarn is sliding on reel 34 . In this case, the tension control is bypassed and the reel is automatically driven to rotate to its resting position N=0.
[0033] Accordingly, with this embodiment, signal LE is used as a comsumption indicator that is indicative of the delivery of yarn from the feeder and, therefore, of the withdrawal of yarn by the downstream machine; on the basis of this indicator, electronic brake 28 and yarn-recovering device 32 are alternately enabled as discussed above.
[0034] Having now reference to FIG. 5 , a weft feeder 100 is diagrammatically shown, which is provided with a motorized drum 102 on which yarn F′ is wound. Motorized drum 102 draws yarn F′ from a spool 104 and delivers it to a textile machine 106 arranged downstream. The tension of yarn F′ unwinding from the feeder is conventionally controlled in such a way as to remain substantially constant on a reference value T_ref, by a control unit CU′ (which is typically incorporated in yarn feeder 102 ) provided with a tension control block TC′ that modulates the speed of rotation V of drum 102 on the basis of the signals from a tension sensor 108 installed on the feeder. Accordingly, the change of tension to be applied is determined by the difference between the yarn-feeding speed and the yarn-drawing speed set in downstream machine 106 .
[0035] A yarn-recovering device 120 is arranged between motorized drum 102 and the tension sensor; in the present embodiment, it is incorporated in housing 103 of feeder 100 , as shown in more detail in FIGS. 6-11 . Yarn-recovering device 120 comprises a motorized reel 122 lying with its axis parallel to the axis of motorized drum 102 . Also in this case, the motor (not shown) of reel 122 is preferably a stepping motor or, alternatively, a brushless motor provided with an absolute sensor for measuring its real position. A passage 124 is defined within reel 122 , which extends radially between an inlet port 126 , which is formed at the middle of a free end 122 a of the reel with its axis inclined with respect to the axis of reel 122 , and an outlet port 128 formed on the lateral winding surface 122 b of the reel. Inlet port 126 and outlet port 128 are internally rounded for reducing the wear by friction.
[0036] Yarn F′ from spool 104 passes through an inlet yarn-guide eyelet 130 attached to the feeder, is wound between drum 12 and an arm 132 of a conventional tension limiter (which does not fall within the scopes of the present invention and, therefore, will not be further disclosed), runs through passage 124 which, at rest, lies at the resting position of FIG. 10 such that it substantially does not interfere with the path of the yarn, then engages a sensing element 134 of tension sensor 108 , the latter being also incorporated in housing 103 of the feeder, and finally passes through an outlet yarn-guide eyelet 136 to feed the downstream machine As shown in FIGS. 6-11 , control unit CU′ is conventially received in a seat 138 of feeder 100 , which also contains tension sensor 108 , and is provided with programming push buttons 140 and with a display 142 .
[0037] With the method according to this alternative embodiment of the invention, which is diagrammatically shown in the flowchart of FIG. 12 , drum 12 of the feeder and reel 122 of yarn-recovering device 120 are alternately enabled as a function of speed V RP of drum 102 , independently from any other operative signal from the downstream machine
[0038] In particular, as long as speed V RP of drum 102 is higher than zero, which circumstance is indicative of the fact that yarn is being delivered by the feeder and, consequently, is being drawn by the downstream machine, drum 102 continues to rotate at a modulated speed, in such a way as to maintain the tension substantially constant on reference value T_ref, while reel 122 remains at its resting position of FIG. 10 . When speed V RP of the drum becomes equal to zero, which circumstance is indicative of the fact that the feeder has stopped to feed yarn and, therefore, the downstream machine has either stopped to draw yarn or started to return it, control unit CU′ enables reel 122 to recover yarn at a speed V RR modulated in such a way as to maintain the tension substantially constant on a reference value T_ref. At this stage, the number of revolutions and fractions of revolutions N completed by reel 122 is monitored.
[0039] Similarly to the previous embodiment, reel 122 can rotate in both directions at a modulated speed. In fact, after an initial yarn-recovering step, in which the exceeding yarn is wound on reel 122 in order to maintain the tension at the desired level T_ref, the next request of yarn from the downstream machine will cause reel 122 to rotate in the opposite direction, always at a controlled speed, in order to return the yarn; however, before reaching the initial position (N=0), it could have to recover yarn again. When the reel reaches the initial position N=0, control unit CU′ stops reel 122 , enables drum 102 again, and then the cycle is repeated.
[0040] With this embodiment, there is also provided an emergency condition, by which the tension control can be bypassed. In particular, when N reaches a value N_max corresponding to the maximum amount of yarn which can be stored on the reel, the process is stopped and an alarm signal is generated. Accordingly, with this embodiment the speed V RP of the drum is used as a comsumption indicator, which is indicative of the delivery of yarn by the feeder and, consequently, of the withdrawal of yarn by the downstream machine; on the basis of this indicator, drum 102 and reel 122 are alternately enabled according to the above method.
[0041] A few preferred embodiments of the invention have been described herein, but of course many changes may be made by a person skilled in the art within the scope of the claims. In particular, in the first described embodiment a stabilizing brake as described in EP 1059375, which applies a controlled braking action to the unwinding yarn, could be used in lieu of electronic brake 28 . Moreover, in the described embodiments, the yarn-recovering device is always positioned in such a way that, at rest, it can assume positions not interfering with the yarn, as shown in FIG. 2 for the first embodiment and in FIG. 10 for the second embodiment. However, depending on the layout of the textile line, the reel could be arranged in such a way as to deviate the yarn even at its resting position in which it applies the minimum braking action upon the yarn.
[0042] The disclosures in Italian Patent Application No. TO2012A000261 from which this application claims priority are incorporated herein by reference. | A textile machine receives yarn from a yarn-feeding device via a yarn-recovering device provided with a motorized reel having a passage for the yarn, which extends between an inlet port open to the middle of the free end of the reel and an outlet port formed on the lateral surface of the reel; the tension of the yarn being maintained constant on a reference value by adjusting elements, on the basis of a measured tension signal generated by a sensor; a consumption indicator being obtained to detect an interruption in the delivery of yarn, the adjusting elements being temporarily disabled and the yarn-recovering device being temporarily enabled to rotate at a speed modulated on the basis of the measured tension signal for maintaining the tension of the yarn constant on the reference value, if an interruption in the delivery of yarn is detected. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Application No. 61/302,287 entitled BREAKER TRAY, filed on Feb. 8, 2010 which is incorporated herein by reference in its entirety and to which this application claims the benefit of priority.
FIELD OF THE INVENTION
This invention relates to panelboards, and more particularly, to a breaker tray for a panelboard cover that enables conversion of the cover from one that is suitable for use with a main lug panelboard to a cover suitable for a main breaker panelboard.
BACKGROUND OF THE INVENTION
Panelboards and load centers used in electrical distribution systems typically include a deadfront, door, trim or other type of cover which is mounted to an enclosure. The cover is typically fabricated from sheet metal and includes removeable sections known as twistouts each of which, when removed, provide an opening for a handle of a device such as a circuit breaker to enable operation of the circuit breaker.
The twistouts are generally configured as rectangularly shaped sheet metal blanks. Each twistout is attached to the cover by a metal tab. During installation, the twistouts are manually removed from the cover by a contractor or electrician by repeatedly bending or twisting the metal tab until the tab breaks thus separating the twistout from the cover and forming an opening. This allows the circuit breaker handle to protrude through the opening and enables assembly of cover to the panelboard enclosure. Removal of the twistouts is a difficult and labor intensive operation and requires the use of special tools.
A panelboard may be configured as either a main lug panelboard or a main breaker panelboard each having different cover configurations. In particular, the cover used in a main breaker panelboard includes an opening for accommodating a breaker handle whereas the cover used in a main lug panelboard does not have the opening. Therefore, manufacturers typically provide two different types of covers in order to accommodate each panelboard configuration.
During on-site installation of an electrical distribution system, it is frequently desirable to convert a cover originally configured for a main lug panelboard to a cover which is suitable for a main breaker panelboard. This requires that an opening be manually cut into the main lug cover by an installer. However, this is also labor intensive and in many instances cannot be done in the field. In order to facilitate the conversion, manufacturers also supply covers having a twistout section for creating an opening in the cover. These types of covers may be used in either a main lug panelboard configuration wherein the twistout is left in place, or in a main breaker configuration wherein the twistout is removed to form an opening for accommodating a breaker handle. As previously described however, removal of a twistout is a difficult and labor intensive operation and requires the use of special tools.
Therefore, there is a need for a cover which reduces the amount of labor needed to form openings for accommodating a handle of a device, such as a circuit breaker, and wherein the opening may be formed without the use of special tools.
SUMMARY OF THE INVENTION
A cover for use with a panelboard enclosure is disclosed. The cover includes a cover element for mounting onto the panelboard enclosure. The cover element further includes an insert which is inserted into a cover element opening. A plate section is attached to the insert along peripheral edges of the plate section by a thin wall section sized to enable separation of the plate section from the insert to thereby provide a tray opening to accommodate a handle of an electrical device.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 a - 1 c depict front, side and bottom views of a breaker tray.
FIG. 1 d depicts a front view of the breaker tray and a tray opening.
FIG. 1 e is an enlarged view of balloon section 1 in FIG. 1 c and depicts a snap.
FIGS. 2 a - 2 b depict left and right rear perspective views of the breaker tray.
FIGS. 2 c - 2 d depict left and right rear perspective views of an alternate embodiment of the breaker tray.
FIGS. 3 a - 3 b depict front and side views, respectively, of the breaker tray assembled into a cover for use with a panelboard.
FIG. 3 c depicts the cover and a cover opening for receiving the breaker tray.
FIG. 4 is a bottom cross sectional view of the breaker tray installed in the cover.
FIG. 5 is an enlarged view of balloon section 5 of FIG. 4 and depicts an edge of the cover inserted into a tray gap.
DESCRIPTION OF THE INVENTION
Before any embodiments of the invention are explained in detail, it should be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it should be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings. In the description below, like reference numerals and labels are used to describe the same, similar or corresponding parts in the several views of FIGS. 1-5 .
Referring to FIGS. 1 a - 1 b , front and side views, respectively, of a breaker tray 10 in accordance with the present invention are shown. FIG. 1 c depicts a cross sectional bottom view of the breaker tray 10 . The breaker tray 10 has a substantially rectangular shape and includes a plate section 14 having a pull tab 12 . The plate section 14 covers a tray opening 21 (see FIG. 1 d ) in the breaker tray 10 which is sized to enable a handle of a device used in an electrical distribution system, such as a handle of a main breaker, to protrude through the tray opening 21 to enable operation of the main breaker.
Referring to FIGS. 2 a - 2 b , left and right rear perspective views of the breaker tray 10 are shown. The breaker tray 10 may be fabricated from a nonmetallic material that has suitable flexibility and impact properties such as plastic. Peripheral side 17 and bottom 19 edges of the plate section 14 are attached to the breaker tray 10 by a thin wall section that is sized and configured relative to the plate section 14 such that pulling on the pull tab 12 in a downward direction causes the plate section 14 to separate from the breaker tray 10 to thus provide the tray opening 21 . A panel gap 38 may be formed between a top edge 15 of the plate section 14 and the breaker tray 10 to assist in removal of the plate section 14 . In one embodiment, the plate section 14 may include perforations to assist in removal of the plate section 14 . Referring to FIGS. 2 c - 2 d , an alternate embodiment of the breaker tray 10 is shown wherein the plate section 14 does not include the pull tab 12 . In this embodiment, an operator simply pushes on the plate section 14 with a finger to thus separate the plate section 14 from the breaker tray 10 and provide the tray opening 21 .
Referring to FIGS. 3 a - 3 b , front and side views, respectively, are shown of the breaker tray 10 assembled into a cover 16 for use with a panelboard. The panelboard may be either a main lug panelboard or a main breaker panelboard. The cover 16 may be either metallic or non-metallic and serves as a barrier between electrical elements within an enclosure and an operator. The cover 16 includes a cover opening 22 (see FIG. 3 c ) defined by edges 30 to form a substantially rectangular shape for receiving the breaker tray 10 . The cover opening 22 is formed by a die or tool during manufacture of the breaker tray 10 at a factory.
FIG. 3 a depicts the cover 16 in a configuration suitable for use with a main lug panelboard wherein the plate section 14 is not removed from the breaker tray 10 . Removal of the plate section 14 from the breaker tray 10 provides the tray opening 21 (see FIG. 1 d ) through which a breaker handle protrudes to enable manual operation of the breaker (i.e. switching the breaker on/off) as needed without physically removing the cover 16 . This converts the cover 16 to a configuration which is suitable for use with a main breaker panelboard.
Therefore, the cover 16 may be used in either a main lug panelboard configuration wherein the plate section 14 is left in place, or in a main breaker configuration wherein the plate section 14 is removed to provide the opening 21 for accommodating a breaker handle. It is frequently desirable to convert a cover originally configured for a main lug panelboard to a cover which is suitable for a main breaker panelboard during an on-site installation of an electrical distribution system. The current invention enables the cover 16 to be quickly converted from a main lug application to a main breaker application without the use of specialized tools. As a result, a manufacturer only needs a single cover manufactured in accordance with the present invention rather than separate covers for each configuration, thus simplifying supply chain management.
Referring back to FIG. 1 c , the breaker tray 10 further includes snap elements 18 located on sides 34 of breaker tray 10 . The snap elements 18 are used to secure the breaker tray 10 to the cover 16 . FIG. 1 e is enlarged view of balloon section 1 of FIG. 1 c and depicts an exemplary snap element 24 . The snap element 24 is spaced apart from a flange 26 to form a tray gap 36 having a height C for receiving the edge 30 of the cover 16 . The snap element 24 has a height H, width W and a sloping portion 32 having an angle A. In one embodiment, gap G is approximately 0.060 in., height H is approximately 0.312 in., width W is approximately 0.180 in. and angle A is approximately 22.6 degrees. In one embodiment, the breaker tray 10 includes four snap elements 18 .
Referring to FIG. 4 , a bottom cross sectional view of the breaker tray 10 installed in the cover 16 is shown. FIG. 5 is an enlarged view of balloon section 5 of FIG. 4 and depicts the edge 30 of cover 16 inserted into the tray gap 36 . The breaker tray 10 is assembled into the cover 16 by applying a downward force to the breaker tray 10 in a direction substantially perpendicular to the cover 16 . This causes contact between sloping portion 32 and the edge 30 , thus causing the snap element 24 to deflect to enable insertion of the breaker tray 10 into the cover opening 22 . After the edge 30 moves past the sloping portion 32 and into the tray gap 36 , the snap element 24 returns to its original shape thus capturing the edge 30 within the tray gap 36 and securing the breaker tray 10 .
While the invention has been described in conjunction with specific embodiments, it is evident that many alternatives, modifications, permutations and variations will become apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended that the present invention embrace all such alternatives, modifications and variations. | A cover for use with a panelboard enclosure. The cover includes a cover element for mounting onto a panelboard enclosure. The cover element includes an insert for insertion into a cover opening. A plate section is attached to the insert along peripheral edges of the plate section by a thin wall section to form a cover suitable for use with a main lug panelboard configuration. The thin wall section is sized relative to the plate section to enable separation of the plate section from the insert by a user to then form a cover suitable for use with a main breaker panelboard configuration. | 8 |
This application claims priority from provisional application Ser. No. 60/072,168, filed on Jan. 6, 1998.
FIELD OF THE INVENTION
The present invention relates to an optical coupler and system for distributing light in a 360-degree pattern, and more particularly to such a coupler and system for distributing light in the mentioned pattern at a small angle above and below a plane.
BACKGROUND OF THE INVENTION
Boats and other water-going vessels are often required to display a light on the highest part of the vessel. Because the highest point is usually the top of a mast which may support sails or radio antenna, for instance, it may be difficult to replace a failed lamp in that location. It, therefore, would be desirable to employ a lamp located at the base of the mast, where it is easily reached, and to direct the light to the top of the mast with a fiber-optic, or light, guide. However, the problem arises of how to distribute the light reaching the upper end of the light guide to meet a required beam pattern. The required pattern for at least one class of ships is to provide 94 candela for 360 degrees in a horizontal plane and which extends 7½ degrees above and 7½ degrees below the horizontal plane.
SUMMARY OF THE INVENTION
An exemplary embodiment of the invention comprises an optical coupler for distributing light in a 360-degree pattern at a small angle. The coupler includes a solid rod with a first end region for receiving light and a second end region for distributing light. The rod tapers up in cross-sectional dimension between the first and second regions so as to decrease the angular distribution of light reflecting internally from the sides of tapered portions of the rod. An axis extends from the second end region towards the first end region. The second end region includes a generally conically shaped void pointing towards the first end region and defining a surface for deflecting light in a 360-degree pattern about the axis at a small angle compared to light entering into the first end region.
The foregoing embodiment provides an output device for distributing light in the required pattern which minimizes light loss and is simple to manufacture and compact.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of an optical coupler in accordance with the invention.
FIG. 2 is a plan view of a light input port of the coupler of FIG. 1 .
FIG. 3 is a plan view of a light output port of the coupler of FIG. 1 .
FIG. 4 is a side view of the coupler of FIG. 1 showing the paths of various light rays and various dimensions.
FIG. 5 is a block diagram of a complete light system incorporating a coupler such as shown in FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment for distributing light from the end of a light guide (not shown) in the required pattern is illustrated in FIGS. 1-3. FIG. 1 shows an optical coupler 10 with an input end region 12 and an output end region 14 , each preferably centered about a longitudinal axis 15 . Side wall 16 of coupler 10 may taper from input region 12 to output region 14 , and, if desired, may also taper in regions 12 and 14 . The tapers are preferably uniform. An input light port 18 , shown also in FIG. 2, receives light from a light guide (not shown) and passes it into the body of coupler 10 . An output port 20 , preferably conically shaped, also shown in FIG. 3, is used for distributing light in a desired pattern.
FIG. 4 shows a further side view of coupler 10 , illustrating various light rays with respect to axis 15 and a plane 22 orthogonal to the axis and representing a horizontal plane when the coupler is attached to the mast of a boat or other vessel, for instance. “Horizontal” and other orientations mentioned herein are merely exemplary. A light ray 24 a received through port 18 totally internally reflects from angled surface 20 to propagate as light ray 24 b . As FIG. 4 illustrates, light ray 24 b is oriented at only a small angle with respect to plane 22 , e.g., 7½ degrees above or 7½ degrees below plane 22 , or a resulting angle of 15 degrees. “Small” angle refers herein to angles generally less than approximately 40 degrees, and preferably less than approximately 20 degrees. Totally internally reflected light rays such as ray 24 b provide the desired distribution of light.
Light ray 26 illustrates the maximum angle 28 of light that is not reflected from wall 16 of the coupler, the light entering a peripheral portion of input light port 18 and exiting a peripheral portion of output port 20 . Angle 28 may be 7½ degrees, for instance. In contrast, light received through input port 18 typically has an angular spread of 30 to 40 degrees half angle. In this connection, the taper of coupler wall 16 results in an angle-to-area conversion for reducing the angle of light received from the input port. Where an especially large angle-to-area conversion is desired, the taper may define a compound parabolic reflector made in accordance with non-imaging optics, a technology known per se in the art. Preferably, a substantial axial length, or the full axial length, of coupler wall 16 is tapered in output region 14 from the axial center 29 of output port 20 to the top of coupler 10 . This causes such axial length of the coupler to function both as an area-to-angle coupler and as a means of directing light (e.g., ray 24 b ) into a desired pattern.
FIG. 5 shows a light system incorporating a coupler 30 , which may be as shown, for instance, in FIG. 1. A light source 32 may typically comprise a small source placed in an elliptical reflector so as to image the source onto the input end (not shown) of a light guide 34 , such as a ½-inch diameter large core plastic optical fiber (LCPOF). A preferred light source is an XMH60P1 source made by GE Lighting of Cleveland, Ohio. It can introduce more than 2000 lumens into a ½-inch diameter LCPOF. An SEL500LCPOF produced by Lumenyte International Corporation of Irvine, Calif. transmits light with an efficiency of more than 0.985 per foot, so a typical mast of 25 height will transmit more than 0.685 of the incident light. With light provided to the light guide of 2000 lumens, light output from the light guide will therefore be 1370 lumens for 25 feet of light guide. If optical coupler 30 reduces the angular spread of light from 30-40 degrees to 7½ degrees in the vertical direction, the 1370 lumens are available to produce a desired light pattern. The total solid angle in a light beam 15 degrees wide and covering all 360 degrees is 1.64 steradian. If there are no other losses, the available flux is 1370/1.64 lumens per steradian or 836 candela, which is well in excess of the required 94 candela.
Referring again to FIG. 1, the tapering of coupler wall 16 reduces the angle of the light entering input port 18 . The input port is preferably just slightly larger in cross-sectional dimension than the core of light guide 34 (FIG. 5 ), or slightly more than ½-inch in diameter for the mentioned LCPOF. An appropriate size for the output end of the taper can be determined from the known angle-to-area relationship wherein the mathematical product of the area of an emitter (or output) and the solid angle of the emitted light, and the same factors for a receiver (or input), are the same. In the mentioned example, the area of input end times the solid angle corresponding to 40 degrees plane angle equals the area of output times the solid angle corresponding to a 7½ degree plane angle. Diameter D (FIG. 4) of the output end of coupler 10 can be expressed by equation 1 as follows:
[pi (0.25) 2 ]/4×2 pi (1−cos 30)=[ pi ( D ) 2 ]/4×2 pi (1−cos 7½) (eq. 1)
Solving equation 1 for D shows that D =1.97 inches.
In determining the length L of coupler 10 (FIG. 4 ), it is preferred that the marginal rays such as ray 26 (FIG. 4) which do not reflect from surface 16 not lie at more than 7½ degrees from the axis. FIG. 4 shows this to occur where length L of coupler 10 is at least 8½ inches.
Referring again to light ray 24 b in FIG. 4 that is oriented in a desired pattern, conically shaped output port 20 changes the direction of ray 24 a due to total internal reflection at this surface of the output port. This is because the angle of incidence for almost all of the rays reaching the output port exceeds the critical angle expressed by sine (critical angle) equals 1/n, where n, the index of refraction, for acrylic is about 1.49. If coupler wall 16 tapers over its entire length, the angle at which the output port is cut should not be exactly 45 degrees (half angle) because refraction at outer wall 16 shifts the light rays slightly upwards. To compensate for this effect, the cone angle of the output port may be increased to about 47½ degrees. Alternatively, the upper part of coupler wall 16 in the vicinity of output end region 14 can be made cylindrical so no refraction will occur for the axial rays. In this case, the cone may be oriented at 45 degrees from the axis.
In a working example of the embodiment of FIG. 1, a prototype tapered rod with a conical void in the larger end was fashioned from acrylic, with input port 18 of ½-inch diameter, output port 20 of 2-inch diameter, and a length L (FIG. 4) of 8½ inches. While machining of the acrylic was employed, molding would be more economical for large scale production. A 45-foot length of SEL500 large core plastic optical fiber from Lumenyte International and an XMH60P1 lamp from GE Lighting were employed. Output light was measured 20 feet from the tapered rod, indicating an intensity of 560 candela, or 1.4 foot-candles (lumens per square foot) at 20 feet. Since candela equals foot candles times distance squared, the mentioned 560 candela results from 1.4 times (20) 2 . The width of the output beam of light at 20 feet was approximately 6 feet. The tan (half angle) equals 3/20. The half angle equals 8.5 degrees, or more than required.
The dimensions in the foregoing design example are linearly scalable. Thus, if a fiber-optic cable of ¼-inch diameter is used rather than the ½-inch diameter cable mentioned above, the other mentioned dimensions are also halved.
While the invention has been described with respect to specific embodiments by way of illustration, many modifications and changes will occur to those skilled in the art. For instance, while the foregoing refers to a Xenon metal halide light source and a LCPOF, an incandescent illuminator directing light into glass fibers, for example, can be used instead to provide a suitable light pattern where the optical coupler is appropriately dimensioned. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true scope and spirit of the invention. | An optical coupler for distributing light in a 360-degree pattern at a small angle is disclosed. The coupler comprises a solid rod with a first end region for receiving light and a second end region for distributing light. The rod tapers up in cross-sectional dimension between the first and second regions so as to decrease the angular distribution of light reflecting internally from the sides of tapered portions of the rod. An axis extends from the second end region towards the first end region. The second end region includes a generally conically shaped void pointing towards the first end region and defining a surface for deflecting light in a 360-degree pattern about the axis at a small angle compared to light entering into the first end region. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to spray nozzles; more particularly, the invention relates to a nozzle swivel joint capable of conveying pressurized liquids and which is rotatable a full 180° about its axis of swivel.
The invention finds particular utility in systems requiring the delivery of pressurized liquids, such as paint spraying systems, wherein a coating material is delivered under pressure through a spray nozzle, and wherein it is important to selectively position the spray nozzle relative to the workpiece. In such a system, a plurality of paint spray nozzles are typically positioned adjacent a movable conveyor line, and workpieces of various sizes and shapes are placed on the conveyor line for movement past the spraying station. The spray nozzles are controlled by a timing mechanism and/or position-responsive sensors so as to emit a spray pattern when a workpiece passes in front of each particular spray nozzle. At the time of initial setup, it is important that each spray nozzle associated with a spraying station be selectively positioned for optimal coating of the workpieces. Once the spray nozzles have been optimally positioned, it is important that the nozzles remain in the preselected position for so long as the workpieces are moved past the spraying station. Subsequently, other and different batches of workpieces may be placed on a conveyor line and the respective spray nozzles may be repositioned to optimally coat the new workpieces. Therefore, it is important that the spray nozzle have the capability of variable positioning, while at the same time have the capability of remaining in a fixed position after adjustment.
The present invention accomplishes these advantageous purposes, to provide an adjustable nozzle swivel joint which is sealably positionable over a 180° range about a swivel axis.
SUMMARY OF THE INVENTION
The nozzle swivel joint includes two couplings which are joined together at mutually flat interface surfaces. Each coupling has an axial flow passage, and the two couplings are held together in mutually rotatable position by a manifold with a threaded end; the manifold having inlet and outlet ports respectively aligned to the flow passages in the couplings. The manifold is sealably affixed to one of the couplings, with a gasket forming a seal about the threadable manifold. An O-ring is compressed between the respective flat interface surfaces to provide a limited friction seal for restricting relative rotation between the couplings, while at the same time permitting rotation to occur with a limited amount of force.
It is a principal object of the present invention to provide a nozzle swivel joint having liquid sealing capabilities while being rotationally positionable about a swivel axis.
It is another object of the present invention to provide a nozzle swivel joint capable of 180° rotation about a swivel axis.
It is a further object of the present invention to provide a nozzle swivel joint which is rotatably movable about a swivel axis by a predetermined and limited amount of force.
It is another object of the invention to provide a reliable nozzle swivel joint which may be readily and easily assembled.
It is another object of the invention to provide a nozzle swivel joint in which the sealing characteristics and the rotational resistance of the joint is substantially independent of the extent the joint is tightened during assembly.
The foregoing and other objects will become apparent from the following specification and claims, and with reference to the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an isometric view of the invention in one swivel position;
FIG. 2 shows a partial cross-section view of the invention in a second swivel position; and
FIG. 3 shows an exploded view of the invention with portions cut away.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a preferred embodiment of the nozzle swivel joint 10 is shown in an assembled mode with the nozzle swivel joint 10 at an angle of approximately 90°. The three principal structural elements of the nozzle swivel joint 10 are a first coupling 12, a second coupling 14 and an elongate manifold 16. In the preferred embodiment the first coupling 12 is connected to a liquid supply source or line and is designated a supply coupling. Similarly, the second coupling 14 is connected to a spray nozzle and is designated a nozzle coupling. The embodiment shown has a female threaded connector 20 attached to the supply coupling 12 and a male threaded connector 22 attached to the nozzle coupling 14. As best shown in FIG. 2, the elongate manifold 16 extends through the supply coupling 12 to connect with the nozzle coupling 14.
Shown in FIG. 2, positioned between the elongate manifold 16 and the supply coupling 12, are a first sealing O-ring 24 and a second sealing O-ring 26 each made of an elastomeric material such as Teflon. Positioned between the elongate manifold 16 and the nozzle coupling 14 is a gasket 28. The gasket 28 may be made out of nylon or other resilient materials. Positioned between the supply coupling 12 and the nozzle coupling 14 is a frictional O-ring 30. The frictional O-ring is also of an elastomeric material such as rubber.
Details of the elongate manifold 16 are best shown in FIGS. 2 and 3. The elongate manifold 16 is generally bolt-shaped, having a head 32, a midsection 34 and a threaded end 36. A circumferential groove 38 is located at the midsection 34. An inlet port 40 extends diametrically through the midsection 34 at the circumferential groove 38. An outlet port 42 extends diametrically through the elongate manifold 16 at the threaded end 36. The elongate manifold 16 has an axis A1 extending longitudinally and has a connecting passageway 44 extending along the axis A1 from the threaded end 36 up through to the midsection 34 connecting the inlet port 40 with the outlet port 42. Positioned between the midsection 34 and the threaded end 36 is a collar 50 with a collar gasket seat 52.
Still referring to FIGS. 2 and 3, the supply coupling 12 is comprised of a body 54 which has a bore opening 55 and a bore 56 extending through the body 54. An axis A2 runs lengthwise and an axial flow passage 57 extends perpendicularly from the bore 56 to an inlet opening 58. Shown best in FIG. 3, the bore 56 has an inside surface 59 and an O-ring seat 60. Surrounding the bore opening 55 is a flat downward interface surface 62.
The nozzle coupling 14 is comprised of a body 64 with an axis A3 and a flat upward interface surface 66. The upward interface surface 66 has a bore opening 67 and a bore 68 that extends downward from the upward interface surface 66 into an interior chamber 70. An additional gasket seat 71 surrounds the bore at the upward interface surface 66. The bore 68 has an upper threaded portion 72 and a lower threaded portion 74 above and below the interior chamber 70. Extending from the interior chamber 70 through the body 64 is an axial flow passage 76 exiting the nozzle coupling 14 at an outlet opening 78. The flat upward interface surface 66 has a circular groove 69 concentric with the bore 68. In the embodiment shown the cross-section of the groove 69 is rectangular, however, other shapes would also be effective. The frictional O-ring 30 seats in the circular groove 69.
The cooperation of the elements of the assembled nozzle swivel joint 10 is best illustrated in FIG. 2. The elongate manifold 16 secures the supply coupling 12 to the nozzle coupling 14 with the interface surfaces 62, 66 confronting each other.
The sealing engagement of the manifold 16 to the supply coupling 12 is provided by the sealing O-rings 24, 26. The first sealing O-ring 24 is seated in the first O-ring seat 46 and engages the inner surface 59 of the supply coupling 12. The second sealing O-ring 26 is seated in the second O-ring seat 48 and also engages the inner surface 69 of the supply coupling 12 and the O-ring seat 60.
As the elongate manifold 16 is screwed into the nozzle coupling 14, the gasket 28 is compressed sealingly engaging the nozzle coupling 14 and the elongate manifold 16. The insertion and tightening of the elongate manifold 16 in the nozzle coupling bore 68 is limited by engagement of the flange 52 with the upward interface surface 60 or with the gasket 28. Once tightened, the nozzle coupling 14, along with the elongate manifold 16, is adjustably rotatable relative to the supply coupling 12 about axis A1. The axis A1 thus is a swivel axis for nozzle swivel joint 10.
FIG. 2 illustrates the flat downward interface surface 62 of the supply coupling 12 confronting the flat upward interface surface 66 of the nozzle coupling 14 and compressing the frictional O-ring 30 in the circular groove 69. In the preferred embodiment a gap separates the two interface surfaces 62, 66. The rotational resistance of the nozzle swivel joint 10 is principally provided by the friction between the elongate manifold head 18 and the body of the supply coupling 12 and the friction provided by the frictional O-ring 30.
As best shown in FIG. 2, an annular space 80 is located between the inside surface 59 of the bore, the midsection 34 of the manifold 16, and the interface surfaces 62, 66. This annular space 80 may be filled with grease or other suitable lubricative material to reduce the rotational resistance of the joint 10. The first sealing O-ring 24 isolates any such lubricative materials from liquid in the nozzle swivel joint 10.
The configuration of the nozzle swivel joint 10 allows for easy assembly. Additionally, in that the elongate manifold 16 does not rotate with respect to the nozzle coupling 14, wear and stress on the gasket 28 is minimized. Further, the compression of the sealing O-rings 24, 26 is dictated by the positioning of the valve seats 46, 48, 60 and is substantially independent of the extent of the tightening of the elongate manifold 16 in the nozzle coupling 14. Additionally, the rotational resistance of the nozzle coupling 14 with the elongate manifold 16 is substantially independent of the extent of the tightening of the elongate manifold 16. Thus, any critical tightening tolerance of the elongate manifold 16 into the nozzle coupling 14 during assembly is minimized.
The liquid flow through the swivel joint 10 is as follows: The liquid from a supply source (not shown) enters the nozzle swivel joint 10 through the inlet opening 58, passes through the axial flow passage 57 and into the inlet chamber 82 which is defined by the inner surface 59 of the bore 56 and the circumferential groove 38 on the manifold 16, the liquid then travels into the inlet port 40 in the manifold 16, down the passageway and out the outlet port 42, into the interior chamber 70, out the axial flow passage 76 and out the outlet opening 78 to the spray nozzle (not shown).
The structural elements may be machined or otherwise formed out of various rigid materials such as steel, stainless steel, or aluminum. It is also anticipated other materials such as plastics may be suitable in certain applications.
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. | The nozzle swivel joint includes two couplings which are joined together at mutually flat interface surfaces. Each coupling has an axial flow passage, and the two couplings are held together in mutually rotatable position by a manifold with a threaded end; the manifold having inlet and outlet ports respectively aligned to the flow passages in the couplings. The manifold is sealably affixed to one of the couplings, with a gasket forming a seal about the threadable manifold. An O-ring is compressed between the respective flat interface surfaces to provide a limited friction seal for restricting relative rotation between the couplings, while at the same time permitting rotation to occur with a limited amount of force. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to a handgun holster with a pivotable semirigid strap to prevent withdrawal of the handgun from the holster until the strap is released from a detent locking device and pivoted forward to release the handgun for withdrawal.
Law enforcement officers, and particularly competitive shooters who have a need to carry a handgun normally do so in a holster, and it is important that the handgun be secure in the holster against falling out when the wearer is running or otherwise involved in activity, and against the possibility of withdrawal by someone other than the wearer. Various arrangements have been used to prevent inadvertent withdrawals from the holster, such as, cover flaps, restraining straps, spring mechanisms, custom molding of the holster to fit each gun, and the like. Typical of such holsters are those shown in Bianchi U.S. Pat. No. 4,101,060; Rogers U.S. Pat. No. 4,694,980; Rogers U.S. Pat. No. 4,925,075; Rogers and Clifton U.S. Pat. No. 5,018,654, the latter having a restraint device affixed to the inside of the holster, the device having a spring biased catch for engaging the trigger guard of the holstered handgun. The present invention is an improvement over these prior art holsters.
It is an object of the present invention to provide an improved handgun holster. It is another object of this invention to provide an improved holster having a novel means for restraining the handgun from being withdrawn from the holster until the wearer intends to do so. Still other objects will become apparent from the more detailed description which follows.
BRIEF SUMMARY OF THIS INVENTION
This invention relates to a handgun holster having a quick release withdrawal restraint, the holster having inner and outer sidewalls joined together along the back and the lower front portions to define an inner cavity having an open top and shaped to fit the handgun holstered therein, the holster having a restraining strap bridging the sidewalls across the open top and being pivotally attached at the ends of the strap to each of the sidewalls respectively, at least one pivotal attachment including a detent which prevents pivotal movement of the restraining strap until the strap is moved in a predetermined direction at the at least one pivotal attachment.
In specific and preferred embodiments of this invention the restraining strap is a semirigid material functioning as a spring bias to maintain a pawl in a notch in at least one pivotal attachment, and adapted to be pressed downwardly with preferably a thumb to release the pawl and to pivot the strap away from the handgun.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features believed to be characteristic of this invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings in which:
FIG. 1 is a rear elevational view of the handgun holster of this invention;
FIG. 2 is a left side (inside) elevational view of the handgun holster of this invention;
FIG. 3 is a right side (outside) elevational view showing a spring biased plunger used to position the handgun in the holster of this invention;
FIG. 3A is a partial right side elevational view showing a roller for use in positioning the handgun in the holster;
FIG. 4 is a top plan view of the holster of this invention showing the plunger of FIG. 3;
FIG. 4A is a partial top plan view showing the roller of FIG. 3A;
FIG. 5 is a bottom plan view of the handgun holster of this invention;
FIG. 6 is an enlarged side elevational view of one embodiment of the pivotal attachment between the holster and the restraining strap of this invention with the outside wall of the spool removed so as to view the interior mechanism;
FIG. 7 is a cross-sectional view taken at 7--7 of FIG. 6, but with the outside wall replaced;
FIG. 8 is an enlarged side elevational view of a second embodiment of the pivotal attachment between the holster and the restraining strap of this invention with the outside cover of the detent means removed so as to view the interior mechanism; and
FIG. 9 is a cross-sectional view taken at 9--9 of FIG. 8.
DETAILED DESCRIPTION OF THE INVENTION
This invention is best understood by the following description with reference to the accompanying drawings.
FIGS. 1-5 show the handgun holster of this invention from five different views. The handgun holster is a holster preferably molded and shaped to receive and hold any chosen handgun, whether it be a revolver or a pistol, although this particular style is adapted best to holster a semi-automatic pistol. The holster is made by known techniques which involve molding the holster to fit the particular contours of the chosen pistol. The resulting holster is semirigid and may be ornamented on the outside with whatever surface decoration is desired. The inside surface of the holster has a felted texture to provide a smooth nonfrictional movement when inserting or withdrawing the handgun. The holster has an inside (next to the wearer) sidewall 10 and an outside sidewall 11 joined together at a front portion 13 and at lower a back portion 12 to form an interior cavity 14 with an open top 15 and an open bottom 16. It is optional whether the bottom 16 is open or closed, but preferably it is open to provide easy cleaning, absence of a vacuum buildup during withdrawal of the handgun, etc. The holster sidewalls 10 and 11 may be two separate pieces of material joined at the back 12 and the front 13 by stitching, riveting, screws and nuts, or the like. In the instance shown here sidewalls 10 and 11 are portions of one continuous piece of material which is folded along front portion 13 and sewed together along back portion 12 as at 36.
The principal improvement of this invention lies in the structure and operability of bridging strap 17 which swans the open top 15 of the holster and is pivotally attached to the top portions of the sidewalls 10 and 11, respectively. The pivotal attachments of bridging strap 17 to sidewalls 10 and 11, respectively, is by means of bolts or screws 21. Bridging strap 17 is adapted to pivot forwardly or upwardly about screws 21. On one of these attachments (shown here to be the attachment between strap 17 and inside sidewall 10) is a detent mechanism designed to maintain strap 17 in its upright position shown in the drawings until unlocked by thumb pressure and pivoted forward to the broken line position 39 to free the handgun from any restraint against withdrawal.
Bridging strap 17 has a spring portion 18 made of a semirigid material which is bent as shown in FIG. 1 and thereby is biased to straighten its bent portion 18 which translates into a force upward in the direction of arrow 40 for the holster shown herein.
The attachment of strap 17 to screw 21 at the top portion of sidewall 10 is shown in enlarged views of FIGS. 6-9. Bridging strap 17, particularly springy section 18, is attached to vertical leg 24, preferably made of an appropriate plastic or other low friction material. In the embodiment of FIGS. 6-7 leg 24 has an enlarged cutout portion 28 which encircles central body 26 of spool 23. Spool 23 is a thin member, somewhat like the bobbin of a sewing machine, consisting of a central cylindrical body 26 separating two closely spaced end walls 25. These three components, body 26 and end walls 25 are rigidly joined together, in this instance by pins or rivets 34, although other joining methods such as cementing, welding, bolting, etc., may be used. Central body 26 contains a notch 27, and a through bore 41 through which the shaft of screw 21 passes to form the pivot means for bridging strap 17. Cutout opening 28 in leg 24 is fashioned with a pawl or tongue 29 which is sized to slide into and out of notch 27. Notch 27 and pawl 29 are oriented to be on the bottom side of screw 21, that is, on the opposite side of through bore 41 from the juncture of leg 24 and bridging strap 17, 18. The upper end of leg 24 is fastened to bridging strap 17, 18 by rivets 35 and is shaped to form a thumb ledge 19. Cutout opening 28 is larger than central body 26 of spool 23 permitting leg 24 to pivot around central body 26 except when pawl 29 is engaged with notch 27. The spring action of semi-rigid portion 18 of bridging strap 17 acts to maintain leg 24 in its most upward position where pawl 29 is engaged in notch 27. When the wearer's thumb is pressed, in a predetermined direction, herein shown as generally downwardly, on ledge 19, pawl 29 clears notch 27 and frees leg 24 to be rotated from its upright solid line position, shown in FIGS. 2-4, to its unrestraining broken line position 39, shown in FIGS. 2-4. It may be seen that leg 24 is sandwiched between end walls 25 of spool 23, and that spool 23 is positioned against washer 22 fitting around nut 33 that engages screw 21, permitting screw 21 to be tightened without affecting the mobility of leg 24, which is movable up and down in the direction of double arrow 30 and is pivotable in the direction of double arrow 42' when pawl 29 is free of notch 27 spool 23 may be made of plastic or metal.
In the embodiment of FIGS. 8-9 the same general operational features are employed in a different mechanism. A thin metal extension leg 43 depends downwardly from inside leg 24 and is sandwiched between inside cover 45 and outside cover 46. Inside cover 45 is removed in FIG. 8 for illustrative purposes. Leg 43 has a centrally located slot 44 having a vertical lengthwise axis. Slot 44 encircles circular boss 47 projecting inwardly from outside cover 46 and fits into a counterbore 48 in inside cover 45. An aligned bore through boss 47 and counterbore 48 provides a seat for nut 33 which engages screw 21. At the vertically lower portion of leg 43 is a crimped tongue 49, functioning as a pawl, which can slide vertically in the direction of arrow 30 to be engaged in notch 50 in the solid line up position or disengaged from notch 50 in the broken line down position 52. When tongue 49 is disengaged from notch 50 leg 43 can be rotated about boss 47 with tongue 49 sliding in cam groove 53 as restraining strap 17 is moved to forward position 39 (FIG. 2) to release the handgun for withdrawal. The embodiment of FIGS. 8-9 employs a leaf spring 54 around post 55 to maintain an upward force on tongue 49 to assist in keeping it in notch 50 until the wearer releases it by generally downward pressure on inside leg 24 and forward rotation of strap 17. Spring means other than leaf spring 54 can be employed for this purpose.
In order to provide good restraint by strap 17 in preventing unintentional withdrawal of the handgun, it is important to position the handgun so there is no looseness to strap 17 in its contact with the handgun. Two alternate devices are provided for this purpose. In FIGS. 1-5 there is shown a preferred device involving a plunger 20 pushed upwardly by spring 56, contained in a small housing 44 that is fastened in the holster by any convenient means, e.g., by means of screw 37 and nut 38. Plunger 20 presses upwardly against some available surface of the handgun, e.g., the trigger guard. An alternate device is shown in FIGS. 3A and 4A where a horizontal roller 42 is fastened in the interior cavity, e.g., at the location of screw 37 and nut 38. Roller 42 bears against any convenient surface, e.g., the trigger guard. In both instances the purpose of the device is to position the handgun so that restraining strap 17 fits snugly around the rear of the slide or the hammer of the handgun.
It may be seen that the wearer of this holster has the security of the handgun being kept within the holster cavity 14 until the wearer is ready to withdraw the handgun. A single quick movement of part of the hand, preferably the thumb, releases the restraint and permits a rapid draw of the handgun.
While the invention has been described with respect to certain specific embodiments, it will be appreciated that many modifications and changes may be made by those skilled in the art without departing from the spirit of the invention. It is intended, therefore, by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention. | A handgun holster having a pivotable semirigid safety strap which prevents withdrawal of the handgun until the strap is selectively released by a force on the strap from a detent by hand manipulation of the user in drawing the handgun after the strap has been pivoted away from the handgun. | 8 |
BACKGROUND OF THE INVENTION
Field of the Invention
[0001] This invention is directed towards rapidly dispersible absorbent nonwoven fabrics and methods for making and using such products. This invention is especially directed towards rapidly dispersible wet wipes that are flushable through a standard toilet system and disintegrate into easily dispersible fragments that biodegrade after disposal.
[0002] Not-woven textiles are defined with the terminology “nonwoven”. The definition of nonwoven is described in the norm ISO 9092:1988. Absorbent nonwoven fabrics include materials such as dry wipes, wet wipes and cosmetic wipes and masks. They are also materials used in hygiene products like panty liners, sanitary napkins and incontinence products. The nonwoven fabrics used in these applications should fulfil the requirements of European Pharmacopoeia.
[0003] Disposable absorbent wipes such as toilet wet wipes offer high levels of convenience, comfort and efficacy that are greatly appreciated by consumers. However, the popularity of these products has created a need regarding their disposal. General disposal methods used for waste materials such bin disposal for subsequent incineration or landfill are not convenient for the consumers, especially for using of toilet wet wipes. One of the alternative disposal methods is flushing the wet wipes directly into a conventional toilet. Flushing the product in the toilet, dispersing it by mechanical forces and finally biodegrading the material in the sewage system is more convenient and discrete for the consumers. For this disposal method, the suitable material should maintain its structural integrity and strength for use, but also disintegrate readily when flushing into the toilet without causing any blockage in the pumping and drain systems.
[0004] Such products like toilet wipes are pre-moistened wipes. Therefore the nonwoven fabrics used for these applications should maintain their mechanical strength and integrity in the wet state during storage and also be biodegradable in the sewage system.
[0005] Flushable wet wipes are known for example from U.S. Pat. No. 5,629,081 and EP 1 285 985 A1.
SUMMARY OF THE INVENTION
[0006] The object of the invention is to provide a dispersible nonwoven fabric with good tensile strength but which disintegrate readily when flushed.
[0007] By the present invention there is provided a dispersible nonwoven fabric comprising pulp and solvent spun cellulosic fibers characterized in that the solvent spun cellulosic fibers are fibrillated.
DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 shows an unfibrillated Tencel by light microscope,
[0009] FIG. 2 : shows an exemplary fibrillated Tencel by light microscope, and
[0010] FIG. 3 : shows an exemplary fibrillated Tencel by scanning electron microscope.
DETAILED DESCRIPTION OF THE INVENTION
[0011] Especially suited as starting material for the fibrillated fibers are solvent spun short cut cellulosic fibers with a length of 2 to 20 mm, preferably 3 to 12 mm, most preferably 4 to 10 mm. The titer of the solvent spun short cut fibers is 0.9 to 6.7 dtex, preferably 1.3 to 1.7 dtex.
[0012] Preferably the solvent spun short cut fibers are present in the dispersible nonwoven fabric in an amount of 1 to 90 wt.-%, preferably 5 to 40 wt.-%, most preferably 10 to 30 wt.-% based on the fabric.
[0013] A preferred solvent spun short cut fiber is a lyocell fiber, produced according to the Aminoxide-process, which is known e.g. from U.S. Pat. No. 4,246,221 (McCorsley). A suited solvent spun fiber is sold under the trade name “Tencel”.
[0014] The dispersible nonwoven fabric has a weight of 30 to 100 g/m2, preferred of 40 to 60 g/m2 and a thickness of 0.1 to 0.7 mm.
[0015] The dispersible nonwoven fabric may comprise a dispersing aid in an amount of 0.1 to 1% wt.-%, preferably 0.5 to 1 wt.-% based on the fabric.
[0016] To increase the strength, optionally a binder is present in an amount of 0.01 to 5 wt.-%, preferably 0.1 to 0.5 wt.-% based on the fabric, preferably in form of an acrylic resin or epichlorohydrin based resin, such as polyamide-polyamine-epichlorohydrin resins or polyamide-epichlorohydrin resins. Other examples for suited binders are polyethylenimine resins and aminoplast resins.
[0017] Any type of pulps are suited, especially softwood pulps, hardwood pulps or a pulp made from plants like abaca or bamboo.
[0018] The dispersible nonwoven fabric according to the invention has a wet tensile strength in machine direction of 2 to 20 N/5 cm, preferably 3 to 13 N/5 cm and most preferably 3 to 7 N/5 cm based on a basis weight of 60 g/m2 and in cross direction 1 to 10 N/5 cm, preferably 1 to 7 N/5 cm and most preferably 1 to 3 N/5 cm. The wet tensile strength has been measured according to the EDANA Method WSP 110.4 (09) “Standard Test Method for Breaking Force and Elongation of Nonwoven Materials (Strip Method)”.
[0019] One standardized test method for testing the properties of disposable wipes is known from “EDANA Guidance Document for Assessing the Flushability of Nonwoven Consumer Products”. This test is used to assess the dispersibility or physical breakup of a flushable product during its transport through household and municipal conveyance systems (e.g., sewer pipe, pumps and lift stations). This test assesses the rate and extent of disintegration of a test material by turbulent water in a rotating tube. Results from this test are used to evaluate the compatibility of test materials with household and municipal wastewater conveyance systems. The principle of the test method is that the rotation of the tube is used to simulate the physical forces acting to disintegrate a product during passage through household sewage pumps and municipal conveyance systems. In this test the product is placed in a clear plastic tube containing 700 ml of tap water or raw wastewater, which is rotated end-over-end. After a specified number of cycles or rotations, the contents in the tube are passed through a series of screens. The various size fractions retained on the screens are weighed, and the rate and extent of disintegration determined.
[0020] The test material is disintegrating when at least 95% of the size fractions pass a 12 mm screen and the residue is less than 5%.
[0021] The invention also concerns a process for the production of a dispersible nonwoven fabric.
[0022] According to this wet lay process, pulp is dispersed in water and a solvent spun fiber is dispersed in water, either separately or together as a mixture. A dispersing aid such as CMC (Carboxymethyl cellulose) may be added to improve dispersion quality. The dispersions are passed through a refiner either separately or are co-refined. The refining energy is from 20 to 400 kWh/t, prefer 40 to 150 kWh/t. A binder solution may be added to the slurry. In the case of separate refining, the slurries are mixed to form an intimate blend to form one slurry. The slurry is then wet-laid, e.g. on a papermaking machine, to form a sheet. The sheet then passes through a hydroentanglement process either on-line or as a separate off-line process to form a fabric.
[0023] FIG. 1 shows an unfibrillated Tencel (light microscope). Fibrillation or refining is a wet abrasion process that exposes and releases fibrils emerging from the surface region of the filaments. As refining progresses, more fibrils are released from the filaments and the diameter of the residual filaments decreases ( FIG. 2 : light microscope, FIG. 3 : scanning electron microscope).
[0024] In further steps the fabric is sliced into the appropriate format, folded and packed.
[0025] A treatment, preferably an impregnation, with a liquid or lotion can be carried out before packaging.
[0026] The invention is shown by the following examples:
Example 1 and Example 2 (Both Comparative)
[0027] Wetlaid fabrics made of blends of woodpulp (Camfor pulp, a long fiber woodpulp derived from spruce and pine, grown in British Columbia, Canada) with 15% Tencel short cut 1.7 dtex at 6 mm cut length (example 1) or 25% Tencel short cut 1.7 dtex at 6 mm cut length (example 2) without any refining process and without additional of any additives showed a very good dispersibility according to the Tier 1 Test-FG 511.2-Dispersability Tipping Tube Test of the “EDANA Guidance Document for Assessing the Flushability of Nonwoven Consumer Products”. According to example 1, 100% of the disintegrated size fractions pass the 12 mm, the 6 mm and even the 3 mm screen, 21% retain and 79% passes the 1.5 mm screen. But the fabrics did not show a high mechanical strength, both in machine direction (MD) and cross direction (CD) as shown in Table 1.
[0000]
TABLE 1
Dispersibility of samples
Tensile
Mass of each fraction
Thick-
Strength
Elon-
in % in relation
Fabric
ness
wet
gation
to dry mass
Fiber
weight
dry
[N/5 cm]
wet [%]
>12
>6
>3
>1.5
<1.5
Ex
blends
[g/m 2 ]
[mm]
MD
CD
MD
CD
mm
mm
mm
mm
mm
1
15%
60
0.65
2.0
0.9
2.2
8
0
0
0
21
79
Tencel
85%
camfor
pulp
2
25%
57
0.60
1.9
1.2
2.4
5
0
0
0
28
72
Tencel
75%
camfor
pulp
Example 3, 4 and 5
[0028] Blends of woodpulp (Camfor pulp) with 25% Tencel short cut 1.7 dtex at 6 mm cut length including an addition of 0.5% CMC dispersing aid to the slurry. In these trials the pulp/Tencel blend was refined through 1× disc refiner and 4× conical refiners in series to levels of 40 kWh/t and 60 kWh/t. Acrylic dry strength resin was added to the slurry at 1% (based on dry fiber weight). The fabrics were dispersible and the tensile strength of fabrics was improved (Table 2).
Example 6
[0029] A blend of 80% woodpulp (Camfor pulp) with 20% Tencel short cut 1.7 dtex at 6 mm cut length was used to make wetlaid fabrics. Fibers were refined to 100 kWh/t, 1% CMC (based on dry fiber weight) as dispersing aid was added and also 0.5% epichlorhydrin based wet strength resin (based on dry fiber weight) was added to increase the wet strength (Table 2). The fabric was dispersible.
[0000]
TABLE 2
Tensile
Dispersibility of samples
Thick-
Strength
Mass of each fraction in %
Refining
Fabric
ness
wet
Elongation
in relation to dry mass
Fiber
Energy
weight
dry
[N/5 cm]
wet [%]
>12
>6
>3
>1.5
<1.5
Ex
blends
(kWh/t)
[g/m 2 ]
[mm]
MD
CD
MD
CD
mm
mm
mm
mm
mm
3
25%
40
59
0.28
3.6
1.3
4.2
39
0
0
0
55
45
Tencel
75%
camfor
pulp,
4
25%
60
56
0.25
3.3
1.5
5.0
33
0
0
0
53
47
Tencel
75%
camfor
pulp
5
25%
60
60
0.32
3.4
1.5
1.3
6.6
0
0
0
78
22
Tencel
75%
camfor
pulp +
acrylic
resin at
1%
6
20%
100
57
0.23
5.4
2.1
2.8
17
0
11
34
29
26
Tencel
80%
camfor
pulp +
0.5%
epichlor-
ohydrin
Example 7, 8, 9 and 10
[0030] A blend of 75% woodpulp (Camfor) with 25% Tencel short cut 1.7 dtex at 6 mm cut length was used to make wetlaid fabrics. Fibers were refined to 80 kWh/t, 1% CMC as dispersing aid was added and also an epichlorhydrin based wet strength resin was added to increase the wet strength at concentrations of 0.05%, 0.10%, 0.15% and 0.20%. The results, demonstrated in Table 3, show that all samples were dispersible.
[0031] The fabric according to the invention can be used in dry wipes and wet wipes like toilette wipes, facial wipes, cosmetic wipes, baby wipes and sanitary wipes for cleaning and densification as well as in absorbent hygiene products such as panty liners, sanitary napkins and incontinence pads.
[0000]
TABLE 3
Tensile
Dispersibility of samples Mass of
Thick-
Strength
each fraction in % in relation to
Refining
Fabric
ness
wet
Elongation
dry mass
Fiber
Energy
weight
dry
[N/5 cm]
wet [%]
>12
>6
>3
>1.5
<1.5
Ex
blends
(kWh/t)
[g/m 2 ]
[mm]
MD
CD
MD
CD
mm
mm
mm
mm
mm
7
25%
80
58
0.59
3.7
1.6
11
50
0
0
1
64
35
Tencel
75%
camfor
pulp +
0.05%
epichlor-
ohydrin
resin
8
As
80
60
0.53
4.1
1.9
11
50
0
0
4
63
33
Ex. 7
except
with
0.10%
epichlor-
ohydrin
resin
9
As Ex.
80
59
0.29
6.5
2.6
2.9
10
0
27
31
16
26
7
except
with
0.15%
epichlor-
ohydrin
resin
10
As Ex.
80
59
0.42
5.5
2.2
8.8
28
0
2
30
36
32
7
except
with
0.20%
epichlor-
ohydrin
resin | The present invention relates to a dispersible nonwoven fabric comprising pulp and solvent spun cellulosic fibers, characterized in that the solvent spun cellulosic fibers are fibrillated. Furthermore the invention concerns the use of the fabric in dry wipes and wet wipes. | 3 |
This is a continuation-in-part application of application Ser. No. 07/224,467, filed Jul. 26, 1988, U.S. Pat. No. 4,952,314.
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for treating medium consistency pulp in connection with different pulp treatment devices or apparatuses. Washers used for washing pulp are disclosed below as an example.
Several types of washing apparatuses are known from the prior art. Known arrangements include diffusers, drum washers/disc washers and Fourdrinier washers, which clearly differ from each other. Pulp is fed into diffuser washers at a consistency of 10%. The feed consistency for drum washers and Fourdrinier washers is normally between 1 and 3%. Drum washers presently used are, for example, suction washers, wash presses and pressure washers.
A conventional suction washer includes a wire coated drum rotatable in a vat or drum. The casing of the drum includes collecting compartments beneath a perforated plate, which each communicate via their own pipe with the valve system on the shaft at the end of the drum. The filtrate is led from the valve through the drop leg to the filtrate chest. Due to the valve construction the suction effect of the drop leg may be arranged at different positions of the web formation.
Web formation in a suction washer is carried out by arranging--by means of a drop leg--reduced pressure inside the drum rotating in the vat, which reduced pressure draws pulp suspension from the vat and against the drum. The fibers of the pulp thicken on the surface of the drum when the liquid penetrates the drum. The consistency of the fiber suspension in the vat is about 0.5-2%, and the consistency of the pulp layer thickened on the drum is about 10-12%. The web formation zone, in other words the part of the rim of the drum, which in the vat is covered by fiber suspension, is about 140°. The maximum rotational speed of the drum is 2 to 2.5 r/min. If the rotational speed is higher the collecting compartments and pipes of the filtrate are not able to empty.
Washing is carried out as a displacement wash by showering washing liquid on the surface of the drum protruding from the vat, which due to the reduced pressure is absorbed through the pulp layer and displaces a majority of the chemical liquid. The width of the displacement zone is approximately 120°. The typical specific square capacity of the suction washer is about 5 BDMT/m 2 /d, wherein the thickness of the pulp web is about 25 mm. In bleaching, the square capacity of the suction washer is about 8 BDMT/m 2 /d and the thickness of the web is about 30 mm. A washer press comprises a drum with a wire coated or drilled perforated plate casing. The pulp feed is carried out at a consistency of 3 to 4% and the knots, unbeaten particles and respective undesired parts are to be discharged from the pulp prior to the washer. There are compartments on the casing of the drum, from which the filtrate is led out via a chamber at the end rim. The drum may also be open so as to gather the filtrate in the drum and let it flow out through the opening at the end.
The length of the web formation stage is about 90° and that of the displacement stage about 150°. The rotational speed of the drum is about 2 r/min and the specific square capacity about 15 to 20 BDMT/m 2 /d. The consistency of the washed pulp may rise even to 30%, when a press roll is used. The displacement, however, takes place at the consistency of 10%, the thickness of the pulp web being about 50 mm.
As an example of a pressure washer there may be mentioned an apparatus according to Finnish patent publication 71961, which mainly comprises a drilled perforated plate drum having 15 to 20 mm high moldings attached on the surface at the distance of about 200 mm from each other. Filtering compartments are located on the casing of the drum beneath the pulp compartments. The outer rim at the end of the drum includes a valve arrangement through which the filtrate is discharged. The washer may have 3 to 5 stages, in other words the filtrates are led from stage to stage by pumping upstream. The chambers of the washing liquid between different stages are sealed.
Web formation is carried out by feeding pulp into the feed box, the bottom of which is formed of a perforated plate, on which an endless wire cloth is located. The feed box becomes lower towards the washing drum. Liquid is discharged from the pulp in the feed box through the wire cloth and the perforated plate and the pulp is thus thickened on the wire cloth. With the wire cloth moving towards the drum, liquid is continuously discharged from the suspension also due to the pressure caused by the lowered feed box. At the end of the feed box pulp is led to the compartments between the moldings and axial "planks" of length of the drum are thus formed in the compartments. Immediately downstream of the feeding point, the drum has a first washing zone; the apparatus according to said patent publication has five separate zones. A flow of washing liquid is led to each zone, which when pressed through the pulp layer in the compartments of the washing drum displaces the previous liquid there. As mentioned above the filtrates are led upstream from one zone to another. In other words, pure washing liquid is pumped to the last washing zone and the displaced filtrate is led to the second last zone to operate as washing liquid there. Subsequent to the last washing zone the "pulp planks" are removed from the drum, for example, by compressed air blow and are transferred forwards with a screw conveyer.
The specific square capacity of this type of pressure washer when having four stages, is about 2.4 BDMT/m 2 /d. The thickness a "pulp plank" is about 55 mm, and it may reach a consistency of 15 to 17%. The washing water flowing from the compartments, however, dilutes the consistency to 10 to 12%. The consistency of the pulp being fed to the washing drum is 3 to 6%. The rotational speed being used with the drum is about 0.3 rpm.
All said apparatuses, apart from the diffusers are characterized in that the consistency of the pulp being fed to the washer is relatively low, at its maximum 6%. In other words the pulp is to be diluted prior to the washing to less than half of the value of the preceding treating stages, which is 10 to 15%. Thus the amount of liquid in the pulp at least doubles. If it were possible to carry out the washing at high consistency, savings might be gained both in the size of the equipment, in the energy consumption and also in the amount of the filtrate to be led for evaporation. The problem is, however, that there has not been appropriate equipment to feed high consistency, over 6%, pulp to the washer. On the other hand, it is also a known fact that when the pulp thickens the air content of the suspension grows and foam problems arise in the washing. Also other pulp treating devices, such as thickeners, have similar problems.
SUMMARY OF THE INVENTION
The object of the present invention is to eliminate or minimize these problems and to enable the treatment of pulp in the medium consistency zone of approximately 8 to 20%. The apparatus according to the invention feeds the medium consistency pulp in a controlled manner to the treating apparatus.
The object of the invention has been reached by an apparatus comprising means for feeding pulp to said filtering means, said feeding means being formed of a substantially air-tight pressure chamber and a feed duct for supplying pulp to said pressure chamber, said pressure chamber having walls, of which at least one is formed of said filtering means.
The apparatus in accordance with a preferred embodiment of the present invention comprises an outer housing surrounding a stationary liquid pervious cylindrical surface having a rotating liquid pervious cylinder therewithin, said liquid pervious cylindrical surface and said rotating cylinder defining a treatment space for pulp therebetween. Said outer housing and said stationary cylindrical surface form an outer and inner wall of annularly arranged chambers for feeding treating liquid to the pulp in said treatment space. Said treatment space is divided into a number of treatment compartments by means of substantially radial partition walls extending from said rotating cylinder towards said stationary cylindrical surface. The pressure chamber has a bottom wall and a side wall, and is attached by means of its side wall to the outer housing in an air-tight manner so that said rotating cylinder forms said bottom wall of said pressure chamber.
The apparatus in accordance with another preferred embodiment of the invention comprises a feed end, a discharge end, a first wire arranged to travel over a first set of rolls and a second wire arranged to travel over a second set of rolls. The wires form a treatment space therebetween which tapers towards said discharge end and form a wedge shaped gap therebetween at said feed end. The wires have seals at the sides thereof for preventing the pulp from leaking from the sides of said wires. The pressure chamber has a bottom wall and a side wall, said bottom wall being formed partially of said wires and partially of said wedge shaped gap between said wires at said feed end.
The apparatus according to the invention is described in detail below, by way of example and with reference to the enclosed drawings, in which a washer is used as an example.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic sectional view of a preferred embodiment of the present invention arranged in connection with a drum type pulp treating apparatus;
FIG. 2 is a schematic sectional view of another preferred embodiment of the present invention arranged in connection with a belt type pulp treating apparatus;
FIGS. 3, 3a and 4 are schematic illustrations showing alternative locations for feed ducts for introducing pulp into the pressure chamber;
FIG. 5 is a schematic illustration showing a rotor inside the pressure chamber; and
FIG. 6 is a schematic illustration showing an additional device for improving the operation of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following, the invention is mainly disclosed in connection with a pulp washer, but also other pulp treatment apparatuses may come into question. A washer 1 according to FIG. 1 is, in principle, a drum in accordance with U.S. patent application Ser. No. 921,786. The housing 12 of said drum, being preferably pressure-proof, surrounds an annular space divided into chambers 2-6, to which a number of conduits lead. The inner surface of said chambers 2-6 is formed of a cylinder 7 which is permeable to liquid. Inside this cylinder 7 is a rotatably mounted cylinder 8 with an outer surface 18 permeable to liquid. There are axially extending, radial partition walls 9 protruding outwardly from the surface of the rotating perforated liquid pervious cylinder, which partition walls form together with portions of the cylinder surfaces 7 and 18, pulp treating compartments 10, i.e. pulp treating zones or treatment space. To the inside of the outer rim 18 of the cylinder 8, there are arranged liquid chambers 11, from which liquid is led through a valve system (not shown) at the end of the washer from each washing zone (corresponding chambers 2-6) to the preceding zone. In other words, from the last washing zone, from the area of chamber 6 to chamber 5, from the area of chamber 5 to chamber 4, etc. The pulp may be discharged from the apparatus as described in FIG. 1, for instance. The pulp in the form of " planks" 60 falls from the treating compartments 10 along a chute to a screw conveyor 61, which feeds the pulp out of the apparatus. Of course the discharge apparatus shown in the parent patent may also be used.
Compared with the apparatus according to said patent major changes, shown in FIGS. 1-3, have been made to the feed side of the washer. FIG. 1 shows a rough outline of pulp feed means 20, which comprises a feed chamber 22 connected directly to the housing 12 of the apparatus in operative communication with the rotating cylinder surface 18. Such feed means 20 makes possible the feeding of pulp into the washer and the spreading of the pulp into a uniform layer on the rotating cylinder surface 18 at the consistency of the pulp of the immediately preceding mass tower or washing step, in other words air free at a consistency of 8 to 20%. A very important feature of the feed means 20 is its tightness to air. In other words, the feeding of pulp is performed by pumping the medium consistency pulp via duct 24 to a pressure chamber 22 where the pulp is made to spread into a uniform layer in the treatment chambers 10 without contact to outside air. The pulp pumping equipment is preferably provided with gas discharge means so that the pulp introduced into the apparatus is gas free. As the pulp is thick it is advantageous to use a so called MC pump for pumping (MC pumps are manufactured and sold by AHLSTROM PUMPS Inc., Peace Dale, R.I.). The pulp flowing to the pressure chamber 22 does not include harmful amounts of air anymore, neither is there a risk of foaming of the filtrate. As shown in FIG. 1, the pressure chamber 22 may be formed of a substantially semicircular wall portion 26, the axial length of which substantially equals the length of the entire apparatus. However, it is to be noted that other forms of walls may be used, for instance straight walls as described with regard to the embodiment of FIG. 2. It is also possible to divide the pressure chamber into a number of shorter chambers each having an inlet duct for receiving the pulp (see FIG. 3a).
FIG. 2 shows another preferred embodiment in accordance with the invention, where said feed means are arranged in connection with a belt-type dewatering or washing apparatus.
Said belt type treating apparatus is provided with a first wire section 50 having a wire 32 arranged to travel over a first set of rolls, only two rolls being shown, and a second wire section 52 having a wire 34 arranged to travel over a second set of rolls. Said wire sections 50 and 52 have been arranged with respect to each other such that there is a wedge shaped gap between the wires 32 and 34 at both ends of the apparatus, but the gap 54 at the feed end being larger than the one at the discharge end. Thus, the pulp treatment space between the wires 32 and 34 tapers towards the discharge end. The pulp is normally fed between the wires 32 and 34 from a headbox resembling somewhat the feed devices of a paper making machine. A headbox, if used, precludes that the pulp has to be diluted to a low consistency. In addition to the fact that a headbox mentioned cannot be used for treating medium or high consistency pulps, as the pulp would not flow out of the headbox, the pulp would be in contact to outside air, if it were fed in a conventional manner between the wires.
The embodiment shown in FIG. 2 comprises a belt type washer 30 having the upper wire 32 i.e. the first wire section 50, and the lower wire 34 i.e. the second wire section, travelling around end rolls 36 and 38. The sides of the wires 32 and 34 are sealed by means of a side seal 40 so that the pulp between the wires 32 and 34 cannot escape to either side of the apparatus. The side seal 40 is preferably arranged to extend somewhat outside the apparatus at the feed end, where there is arranged a pressure chamber 42 for feeding and spreading the pulp between the wires. The chamber 42 may in principle be of the same structure as the one described in connection with the embodiment of FIG. 1. The chamber 42 shown in FIG. 2 has, however, two planar side walls 44 and 46 tapering towards the feed duct 48. The bottom wall of the chamber 42 is formed of the wires 32 and 34 and the wedge shaped gap 54 therebetween. As the side seals 40 of the apparatus extend preferably at the sides of the pressure chamber 42 forming the side plates thereof, the pressure chamber 42 is sufficiently air tight for not allowing contact of outside air with the pulp to be treated.
In FIGS. 3 and 4 there are shown two ways to arrange the feed of pulp to the pressure chambers 22 and 42. FIG. 3 shows that there may be either one 24, 48 or several ducts 24', 48' for feeding the pulp into the pressure chamber 22, 42. The duct 24 may be located in the center of the apparatus, whereby the pulp is divided in the middle portion of the chamber 22, 42 into two flows flowing in opposite directions thus filling the entire pressure chamber 22, 42. There may, however, be also ducts 24', 48' on both sides of the central duct 24, 48 so that the filling of the pressure chamber is ensured. Similarly, the pressure chamber may be divided in axial partitions (shown in FIG. 3a) such that each one of such partitions is provided with a central feed duct. FIG. 4 shows a duct 24, 48 at the end of the pressure chamber 22, 42, whereby the pulp flows along the pressure chamber 22, 42 all the way to the opposite end of the chamber. It is to be noted that in spite of the fact that only some embodiments have been shown above, also other embodiments are covered by the invention. There may be feed ducts both at the end of the pressure chamber and at the side thereof or, as shown in FIG. 5, there may be a rotating fluidizing rotor 56 arranged in the pressure chamber 22, 42 in case such seems to be needed. Such a rotating rotor may, of course, be used in connection with all kinds of treatment apparatuses, drum-type apparatuses, belt-type apparatuses etc.
Though not shown in the drawings the stationary cylindrical surface 7 shown in FIG. 1 and the chambers 10 may be omitted such that the outer housing of the apparatus faces the rotating cylinder. This is a simplified structure in case the apparatus is used only as a pulp dewatering unit. Also, it is possible to arrange the operation of the apparatus such that the chambers 10 are not used to introduce treatment liquid to the pulp in the treatment space, but to receive filtered liquid therefrom like the chambers 11 inside the rotating cylinder surface.
It is a characterizing feature of the invention that the chambers 22, 42 are limited on one of their sides, called the bottom wall, to a moving surface and its pulp treating compartment. As the pulp is introduced in a highly pressurized state in the pressure chamber the pulp is at least partially fluidized after hitting the walls of the pressure chamber, whereby the pulp is capable of filling the entire space available and forming a uniform pulp layer in the treating compartments. It is necessary for the effective operation of the feed means and for the pressure chamber that it is entirely air-tight so that the pressure or the inertial force of the pulp entering the pressure chamber cannot escape, but is utilized for spreading the pulp in the compartments.
FIG. 6 shows an additional device arranged either in connection with the pressure chamber 22 itself or with the feed duct 24 communicating with the pressure chamber 22. The device 60 comprises a pressure balancing chamber 62 for compensating the pressure pulses created in the apparatus during the feeding of pulp therein. It has been found out that the pressure in the treatment compartment and accordingly in the pressure chamber 22 rises due to the pump pressing pulp towards the chamber. The pressure, however, drops suddenly as a new, empty treatment compartment turns towards the pressure chamber and opens thereto revealing an open space therein. By arranging said pressure balancing chamber 62 as described earlier the pump is able to push pulp into the chamber 62 against gas pressure whereby the pressure in the pressure chamber 22 does not rise that high.
The upper portion 64 of the pressure balancing chamber may be filled with air or some other appropriate gas. Said portion may be in direct communication with the pulp or it may also be separated therefrom by means of rubber bellows or like device 66.
When using the apparatus according to the invention for feeding pulp to a drum type washer, for example, it is possible to utilize the surface of the drum better in the actual washing process, because the feed and discharge apparatuses cover only 60° (degrees) of the entire drum circumference, which leaves thereby 300° (degrees) for washing. Presuming that the thickness of the web of the drum is 30 mm and the rotational speed of the drum 7.5 rpm, the square capacity of the drum becomes more than 32 BDMT/m 2 /d. The outlet consistency may be even 15% without any risk of operational disturbances, because the discharge devices described in the parent application operate reliably at these consistencies. Thus, it is possible to treat the pulp continuously at the consistency of 8 to 20% without a need to dilute it, for example, for the feed to the washer. At the same time it is possible to utilize the feature of a fluidizing centrifugal pump to remove air from high consistency pulp, by means of which the foaming of the filtrates in the washer is prevented or minimized.
As a conclusion, it should be mentioned that the apparatus according to the invention may be applied not only to a washer, but also to other pulp treatment apparatuses, in which pulp is to be fed in the form of a web to the apparatus. Such pulp treatment apparatus may, for example, be a thickener. It must also be understood that although the above description deals only with the application of the invention solely to a drum and belt type of pulp treatment apparatus, it is quite possible to also apply the invention to other types of treatment apparatuses, in other words to all such apparatuses in which the treatment of pulp is carried out on rotating filtering surfaces. Thus, the above described example concerning a washer only has the purpose of showing what a considerable improvement the invention brings relative to the prior art and not that of restricting the invention of what is shown in the enclosed claims, which alone determine the scope of invention. | An appratus for treating medium consistency pulp in connection with different treatment apparatuses, such as washers. According to the prior art the treatment of pulp, for example, the washing process, starts at a low consistency, approximately 1-3% so that it is necessary always to dilute pulp before washing, whereby the water consumption of the plant increases and the need of power in, for example, pumping and in the treatment generally increases. The present invention makes it possible to treat medium consistency pulp, because the feeding means is able to spread the pulp as an even layer on the perforated surface of the treating apparatus. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention pertains to supporting devices such as those used for temporary warning signs and in particular to such support devices which employ adjustable legs and other adjustable components.
2. Description of the Related Art
Frequently, a need arises to provide temporary warnings alongside vehicle roadways, pedestrian walkways and other locations. It has been found convenient to provide temporary warning systems which are readily assembled from a collapsed or small sized storage configuration of relatively small size. Temporary warning signs typically employ ground-engaging legs configured with a base to support an upright mast. Typically, when the sign stand is deployed, the groundengaging legs form an angle with the upright mast that is usually larger than 90°. It is generally preferred that a storage configuration be provided in which the legs are selectively collapsed or folded to a position generally parallel with the upright mast, in order to provide a compact storage and size suitable for construction vehicles and the like. Examples of leg release devices may be found in commonly assigned U.S. Pat. Nos. 4,954,008 and 6,315,253. A collapsible sign stand base for use with an upright fiberglass rib is described in U.S. Pat. No. 4,694,601 and other arrangements are shown in U.S. Pat. Nos. 4,548,379; 4,593,879 and 5,340,068. Despite the favorable acceptance of these designs, improvements are continuously being sought.
SUMMARY OF THE INVENTION
Oftentimes, ground-supporting legs are formed from hollow, rectangular tubing. If possible, it is beneficial to locate components of a leg release assembly within the tubing to prevent unintentional snagging with nearby materials. Furthermore, if most all of the leg release components can be located within the tubing, and optimally a compact storage configuration can be realized. However, until the advent of the present invention, at least some of the leg release components have been mounted outside of the legs, in order to provide a rugged construction, sufficient to adequately retain locking pins in a desired position, despite rough handling associated with construction work, as well as vibrations due to wind gusts. Substantially all of the leg release components employed by the present invention are located within the hollow tubular legs. Exceptions include only the locking pin tip and a smooth actuator button.
It is an object of the present invention to provide a release device for use with support arrangements, such as those found in sign stands.
Another object of the present invention is to provide a release device for use with support legs of collapsible sign systems.
Yet another object of the present invention is to provide leg release devices which can be economically fabricated from a minimum number of inexpensive parts.
These and other objects according to principles of the present invention are provided in a sign stand assembly which is comprises of a sign panel, a support base, an upright mast joining the sign panel and support base. This support base includes a plurality of plate portions which define a locking recess, a plurality of legs that are pivotally connecting the legs to the plate portions. A locking pin carried on one leg, for movement toward and away from the locking recess defined by one leg. An actuator that has an end within said leg for pivotally engaging the pivotal connection. An opposed end with an outwardly protruding button that partially extends outside the leg and a medial portion within the leg that defines an opening for receiving the locking pin in interlocking engagement therewith.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is perspective view of a sign stand assembly with a release mechanism according to principles of the present invention;
FIG. 2 is a perspective view thereof, with the sign stand assembly shown in a collapsed position;
FIG. 3 is a perspective view of the support base portion thereof;
FIG. 4 is a bottom plan view of the arrangement shown in FIG. 2;
FIG. 5 is a cross-sectional view taken along the line 5 — 5 of FIG. 3;
FIG. 6 is a plan view of a spring component thereof;
FIG. 7 is a plan view of a locking pin component thereof;
FIG. 8 is a plan view of an actuator component thereof;
FIG. 9 is an elevational view of the actuator component; and
FIG. 10 is a fragmentary bottom plan view of the sign stand assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, and initially to FIG. 1, the sign stand assembly is generally indicated at 10 . Sign stand assembly includes a sign panel subassembly 12 , which includes a sign panel 14 supported by a horizontal cross member 16 and a vertical cross member 18 , preferably in the form of a fiberglass rib. The bottom portion 24 of the fiberglass rib is mounted in a rib clamping device 34 , which is supported by a vertical body member 30 . Body member 30 is in turn bolted to a bracket 36 resiliently supported by a spring 50 . With reference to FIG. 3, spring 50 is supported by a support assembly 52 including a platform portion 54 supported between side plates 84 . Side plates 84 include ear portions 56 having holes 58 to receive a bolt fastener which provides pivot support for ground-engaging legs 64 (see FIG. 1 ). Ears 56 further include holes 68 which, as will be seen herein, define an extended or operational configuration of the legs as illustrated in FIG. 1 . Ear portions 56 also include holes 72 which define a collapsed storage position for the legs 64 , as illustrated for example in FIG. 2 .
Referring to FIG. 4, ear portions 56 a , 56 b preferably form part of an integral side plate 84 while ear portions 56 c , 56 d form portions of a second side plate 86 . Preferably, side plates 84 , 86 are mirror images of one another although this feature is optional, and can be omitted, if desired. With further reference to FIG. 4, it can be seen that the legs 64 extend outwardly from outer surface portions 84 a , 86 a of side plates 84 , 86 . Pivot members in the form of bolt fasteners 92 pivotally connect legs 64 to the ear portions of side plates 84 , 86 . The legs 64 are located to one side of the ear portions with the bolt fasteners passing through the legs and ear portions. Bolt fasteners 92 have heads located adjacent the inner surfaces 84 b and 86 b . The bolt fasteners 92 extend through legs 64 and are terminated at their free ends by threaded nut fasteners 94 . As can be seen in FIG. 4, the legs 64 comprise hollow tubing and have a preferred generally square cross-sectional shape. If desired, leg 64 can have an elongated, rectangular or non-square cross-sectional shape. With reference to FIGS. 3 and 4, bolts 92 pass through holes 58 formed in the ear portions 56 of plates 84 , 86 .
With reference to FIG. 5, a release assembly is generally indicated at 102 . The release assembly 102 selectively interferes with the legs 64 to lock the legs either in the operational position shown in FIG. 1 or the storage position shown in FIG. 2 . As mentioned, the legs 64 pivot about bolts 92 which are secured to the inner portions of the ears 56 .
With reference to FIG. 3, it can be seen that the holes 58 which receive the bolt fasteners 92 are located at inner portions of the ears 56 while the locking holes 68 , 72 are located at outer portions.
Referring to FIGS. 5 and 10, release assembly 102 includes a locking pin 106 having a head 108 and a tip or free end 110 . The locking pin is carried by leg 64 and preferably extends through the hollow interior of the leg. In FIG. 5, the locking pin is illustrated as extending beyond the outer surface of ear 56 for illustrative purposes. If desired, the locking pin can be configured such that the free end 110 is located at or slightly recessed below the outer surface of ear 56 .
In FIG. 5, the locking pin 106 is shown in a fully extended or locked position. In the preferred embodiment, locking pin 106 has a generally cylindrical body although other cross-sectional shapes can be employed, if desired. Referring to FIG. 7, the medial portion of locking pin 106 defines a pair of opposed locking recesses 114 , the bottom portions of which extend generally parallel to one another. Preferably, locking pin 106 has an elongated generally cylindrical configuration with the recesses 114 being located opposite one another on either side of the longitudinal axis. As will be seen herein, the recesses 114 are dimensioned for interlocking engagement with a keyhole-shaped opening in the actuator.
Referring again to FIG. 5, release assembly 102 further includes a spring member 120 . The spring member 120 is preferably of a flat spring construction having first and second ends and a medial portion between the ends. The first end 122 of the spring defines a relatively shallow recess 124 giving the spring end 122 a forked or stirrup configuration. As schematically indicated in FIG. 6, recess 124 at least partially receives bolt 92 . This arrangement is schematically indicated at the left-hand portion of FIG. 5 with spring end 122 engaging bolt 92 adjacent the threaded nut fastener located at the outside of leg 64 .
Referring again to FIG. 6, the opposed end 128 of spring 120 defines a relatively deeper recess 130 which extends toward spring end 122 . As can be seen in FIG. 6, the recesses 124 , 130 are similar to one another, being located along the longitudinal center line of spring 120 , but differ in their length.
With reference to FIG. 5, the free end 128 of spring 120 is free to move back and forth, toward and away from bolt 92 and locking pin 106 . Recess 130 is made sufficiently long so as to permit locking pin 106 to extend through recess 130 in the manner indicated in FIG. 5 .
Referring again to FIGS. 5, 8 and 9 , release assembly 102 further includes an actuator 150 having a generally flat bar-like body including a first end 152 with a recess 154 for receiving bolt 92 . The opposed end 158 of actuator 150 includes an upstanding button 160 having a rounded free end portion. Button 160 extends from the inside surface 150 a of actuator 150 . In the preferred embodiment, the opposed outside surface 150 b of actuator 150 is relatively flat although outside surface 150 b can take on a non-flat or profiled shape, if desired. The relatively flat surface preferred for the outside 150 b of actuator 150 allows free sliding movement of spring 120 as actuator 150 is moved throughout its range of motion.
Referring again to FIG. 8, the central portion of actuator 150 defines a keyhole-shaped slot 170 . The larger end of keyhole slot 170 receives the body of locking pin 106 allowing the locking pin to be inserted through the actuator to bring recesses 114 in contact with the actuator body. Recesses 1 14 cooperate with the smaller sized end of keyhole slot 170 to allow interlocking engagement between the locking pin and the actuator.
Referring again to FIG. 5, it will now be seen that the actuator 150 and spring 120 are held captive within leg 64 . Button 160 extends slightly beyond the inside surface of leg 64 while the opposite end 152 engages bolt 92 preventing dislocation of actuator 150 toward the left-hand side of FIG. 5 . As button 160 is depressed, locking pin 108 is moved in the direction of arrow 166 , due to the interlocking of actuator 150 and pin 106 . As button 160 is depressed, the outer surface of the actuator pushes against spring 120 causing the spring to compress or flatten slightly, with free end 128 of the spring moving in the direction of arrow 168 . This store spring energy urging actuator 150 to return to its rest position illustrated in FIG. 5 . With button 160 sufficiently depressed, the free end 110 of locking pin 106 is made to clear the plate ear portion 56 , allowing the leg to be pivoted about bolt fastener 92 , with the leg assuming its desired orientation.
The drawings and the foregoing descriptions are not intended to represent the only forms of the invention in regard to the details of its construction and manner of operation. Changes in form and in the proportion of parts, as well as the substitution of equivalents, are contemplated as circumstances may suggest or render expedient; and although specific terms have been employed, they are intended in a generic and descriptive sense only and not for the purposes of limitation, the scope of the invention being delineated by the following claims. | The sign stand assembly includes a sign panel, support base and an upright mast between the two. The support base defines a locking recess and a hollow leg is pivotally connected to a plate portion and extending from the support base. The locking pin and actuator are carried within the hollow leg with the actuator carrying an outward protruding button. The actuator includes a medial portion defining an opening to receive the locking pin in interlocking engagement therewith. | 4 |
BACKGROUND OF THE INVENTION
‘Unicorn’ is a product of a breeding and selection program for outdoor pot mums (garden mums) which had the objective of creating new chrysanthemum cultivars with a decorative type flower, a natural season flower date around August 26-31 ; blooming for a period of 5 weeks. The new plant of the present invention comprises a new and distinct cultivar of Chrysanthemum plant ‘Unicorn’ is a seedling resulting from the open pollination among groups of chrysanthemum cultivars maintained under the control of the inventor for breeding purposes. The new and distinct cultivar was discovered and selected as one flowering plant by Rob Noodelijk on a cultivated field in Rijsenhout Holland in August 2000. The plant has been asexually reproduced by cuttings in greenhouses at Rijsenhout Holland. The new cultivar has been found to retain its distinctive characteristics through successive propagations.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention of a new and distinct variety of chrysanthemum is shown in the accompanying drawings, the color being as nearly true as possible with color photographs of this type.
FIG. 1 shows a plant of the cultivar in full bloom.
FIG. 2 shows the various stages of bloom of the new cultivar.
FIG. 3 shows the petiole and foliage of the new cultivar.
DESCRIPTION OF THE INVENTION
This new variety of chrysanthemum is of the botanical classification Chrysanthemum morifolium. The observations and measurements were gathered from plants grown out door in Rijsenhout, Holland under natural day length and temperature and planted week 22 in 2000 and 2001. The natural blooming date of this crop was August 26-31 (week 35). The average height of the plants was 28 cms. No growth retardants were used. No tests were done on disease or insect resistance or susceptibility. No tests were done on cold or drought tolerance. This new variety produces small sized blooms with white ray florets and a yellow center blooming for a period of 5 weeks.
From the cultivars known to inventor the most similar existing cultivar in comparison to ‘Unicorn’ is ‘Marilyn’(U.S. Plant Pat. No. 11,910). When ‘Marilyn’ and ‘Unicorn’ are being compared the following differences are noticed: The differences of ‘Marilyn’ and ‘Unicorn’ are (1) Flower color. The flowers of ‘Unicorn’ are more pure white. (2) Natural flowering date. ‘Unicorn’ flowers earlier.
The following is a description of the plant and characteristics that distinguish ‘Unicorn’ as a new and distinct variety. The color designations are taken from the plant itself. Accordingly, any discrepancies between the color designations and the colors depicted in the photographs are due to photographic tolerances. The color chart used in this description is: The Royal Horticultural Society Colour Chart, edition 1995.
Table 1. Botanical Description of Cultivar ‘Unicorn’
Bud:
Size.— Medium ;cross-section 1.0 cm, height 1.0 cm.
Outside color.— Yellow 10 D.
Involucral bracts.— 2 rows, length 7 mm, width 3 mm.
Involucral bracts among disc - florets.— Not present.
Involucral bracts color. Green 138 B.
Bloom:
Type.— Decorative.
Height.— Medium. 1.5-2.0 cm.
Size.— Small.
Fully expanded.— 3.5-4.0 cm.
Number of blooms per branch.— Approx. 7-9 blooms per branch.
Performance on the plant.— 5 weeks.
Seeds.— Produced in small quantities, ovate grey-brown 199A, 1½ mm in length.
Fragrance.— Typical chrysanthemum, slightly.
Color:
Center of the flower.— Immature yellow 8 B Mature white 155 D, yellow 8 B at the tips.
Color of upper surface of the ray - florets.— White 155 D.
Color of the lower surface of the ray - florets.— White 155 D.
Tonality from distance.— A garden mum with white flowers and a yellow disc.
Color of the upper surface of the ray - florets after aging of the plant.— White 155 D.
Ray florets:
Texture.— Upper and under side smooth.
Number.— 150-170.
Cross - section.— Convex.
Longitudinal axis of majority.— Reflexing.
Length of corolla tube.— Medium. 0.7-1.0 cm.
Ray - floret margin.— Entire.
Ray - floret length.— 1.8-2.2 cm.
Ray - floret width.— 0.4-0.5 cm.
Ratio length/width.— Medium.
Shape of tip.— Rounded.
Disc florets: (only visible in mature stage).
Disc diameter.— 0.3-0.5 cm.
Distribution of disc florets.— Numerous, sometimes visible at mature stage.
Shape.— Tubular.
Color.— Yellow-green 151 A.
Reproductive shape.— Domed raised.
Reproductive organs:
Stamen ( present in disc florets only ).—Thin. 3 mm in length.
Stamen color.— Yellow-green 144 A.
Pollen.— Sometimes present.
Pollen color.— Yellow 12 A.
Styles.— Thin.
Style color.— Yellow-green 144 A.
Style length.— 3 mm.
Stigma color.— Yellow-green 144 A.
Stigma width.— 1 mm.
Ovaries.— Enclosed in calyx.
Plant:
Shape.— When grown as a spray type pot mum, outdoor mounded and round.
Growth habit.— Vigorous.
Growth rate.— Fast.
Height.— 28 cm.
Width.— 30-34 cm.
Stem color.— Green 138 B.
Stem strength.— Strong.
Stem brittleness.— Absent.
Stem anthocyanin coloration.— Absent.
Length of lateral branch.— From top to bottom 13-14 cm.
Lateral branch color.— Green 138 B.
Lateral branch, attachment.— Flexible.
Branching ( average number of lateral branches ).—Prolific with 8-10 breaks after pinching.
Peduncle length.— 3.5-4.5 cm.
Peduncle color.— Green 138 B.
Natural season blooming date.≧ August 26-31.
Foliage:
Color.— Upper side yellow-green 147 A. Under side yellow-green 147 B.
Size.— Small.; length 4.5 cm, width 4.0 cm.
Quantity ( number per lateral branch ).—8-10.
Shape.— Ovate — round.
Texture upper side.— Glabrous.
Texture under side.— Pubescent.
Venation arrangement.— Palmate.
Shape of the margin.— Serrated.
Shape of base of sinus between lateral lobes.— Acute.
Margin of sinus between lateral lobes.— Diverging.
Shape of base.— Obtuse.
Apex.— Mucronate.
TABLE 2
Differences with the comparison varieties
‘UNICORN’
‘MARILYN’
Color of the upper surface of the ray-
White 155 D
White 155 A
florets
Natural flowering date
August 26-31
September 10-19 | A chrysanthemum plant named ‘Unicorn’ characterized by its small sized blooms with white ray florets and prolific branching; natural season flower date August 26-31; blooming for a period of 5 weeks. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of copending International Application No. PCT/US92/04438 designating the United States and filed Jun. 3, 1992, the entire disclosure of which, except to the extent contrary to any explicit statement herein, is hereby incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to lubricant base stocks, which can also serve as complete lubricants in some cases; compounded lubricants, which include at least one additive for such purposes as improving high pressure resistance, corrosion inhibition, and the like along with the lubricant base stocks which contribute the primary lubricity to the compounded lubricants; refrigerant working fluids including lubricants according to the invention along with primary heat transfer fluids, and methods for using these materials. The lubricants and lubricant base stocks are generally suitable for use with most or all halocarbon refrigerants and are particularly suitable for use with substantially chlorine-free, fluoro-group-containing organic refrigerating heat transfer fluids such as pentafluoroethane, 1,1-difluoroethane, 1,1,1-trifluroethane, and tetrafluoroethanes, most particularly 1,1,1,2-tetrafluoroethane. The lubricants and base stocks, in combination with these heat transfer fluids, are particularly suitable for hermetically sealed compressors for domestic air conditioners and refrigerators, where long lubricant service lifetimes are important because of the difficulty and expense of supplying additional lubricant after the initial assembly of the compressor.
[0004] 2. Statement of Related Art
[0005] Chlorine-free heat transfer fluids are desirable for use in refrigerant systems, because their escape into the atmosphere causes less damage to the environment than the currently most commonly used chlorofluorocarbon heat transfer fluids such as trichlorofluoromethane and dichlorodifluoromethane. The widespread commercial use of chlorine-free refrigerant heat transfer fluids has been hindered, however, by the lack of commercially adequate lubricants. This is particularly true for one of the most desirable working fluids, 1,1,1,2-tetrafluoroethane, commonly known in the art as “Refrigerant 134a” or simply “R134a”. Other fluoro-substituted ethanes are also desirable working fluids.
[0006] Esters of hindered polyols, which are defined for this purpose as organic molecules containing at least five carbon atoms, at least 2 —OH groups, and no hydrogen atoms on any carbon atom directly attached to a carbon atom bearing an —OH group, have already been recognized in the art as high quality lubricant basestocks for almost any type of refrigeration machinery employing a fluorocarbon refrigerant, particularly one free from chlorine. The following patents and published patent applications also teach many general classes and specific examples of polyol esters useful as refrigerant lubricants with chlorine-free fluoro group containing heat transfer fluids: U.S. Pat. No. 4,851,144; UK 2 216 541; U.S. Pat. Nos. 5,021,179; 5,096,606; WO 90/12849 (Lubrizol); EP 0 406 479 (Kyodo Oil); EP 0 430 657 (Asahi Denka KK); EP 0 435 253 (Nippon Oil); EP 0 445 610 and 0 445 611 (Hoechst AG); EP 0449 406; EP 0 458 584 (Unichema Chemie BV); and EP 0 485 979 (Hitachi).
DESCRIPTION OF THE INVENTION
[0007] Except in the claims and the operating examples, or where otherwise expressly indicated, all numerical quantities in this description indicating amounts of material or conditions of reaction and/or use are to be understood as modified by the term “about” in defining the broadest scope of the invention. Practice of the invention within the boundaries corresponding to the exact quantities stated is usually preferable, however.
[0008] More specifically, esters according to this invention should have a viscosity of not more than 44, or with increasing preference in the order given, not more than 42, 40, 38.5, 37.2, 36.6, 36.2, 35.7, or 35.2, centistokes at 40° C. Independently, esters according to this invention should have a viscosity of at least 22.5, or with increasing preference in the order given, at least 23.9, 25.0, 25.9, 26.7, 27.4, 28.0, 28.5, 29.0, 29.4, or 29.8, centistokes at 40° C.
[0009] It has now been found that selected polyol esters provide high quality lubrication for this kind of service. Specifically effective are esters or mixtures of esters made by reacting (i) a mixture of alcohol molecules selected from the group consisting of 2,2-dimethylol-1-butanol (also known as “trimethylolpropane” and often abbreviated hereinafter as “TMP”); di-trimethylolpropane (often abbreviated hereinafter as “DTMP”), a molecule with four hydroxyl groups and one ether linkage, formally derived from two molecules of TMP by removing one hydroxyl group from one of the TMP molecules and one hydrogen atom from a hydroxyl group of the other TMP molecule to form water and join the two remainders of the original TMP molecules with an ether bond; 2,2-dimethylol-1,3-propanediol (also known as “pentaerythritol” and often abbreviated hereinafter as “PE”); and di-pentaerythritol (often abbreviated hereinafter as “DPE”), a molecule with six hydroxyl groups and one ether bond, formally derived from two PE molecules by the same elimination of the elements of water as described above for DTMP, with (ii) a mixture of acid molecules selected from the group consisting of all the straight and branched chain monobasic and dibasic carboxylic acids with from four to twelve carbon atoms each, with the alcohol moieties and acyl groups in the mixture of esters selected subject to the constraints that (a) a total of at least 3%, or, with increasing preference in the order given, at least 7, 10, 14, 16, or 19%, of the acyl groups in the mixture 2-methylbutanoyl or 3-methylbutanoyl groups, which are jointly abbreviated hereinafter as “acyl groups from i-C 5 acid”; (b) the ratio of the % of acyl groups in the mixture that contain 8 or more carbon atoms and are unbranched to the % of acyl groups in the mixture that are both branched and contain not more than six, preferably not more than five, carbon atoms is not greater than 1.56, more preferably not greater than 1.21, or still more preferably not greater than 1.00; (c) the % of acyl groups in the ester mixture that contain at least nine carbon atoms, whether branched or not, is not greater than 81, or increasingly more preferably, not greater than 67 or 49; and (d) not more than 2, more preferably not more than 1, or still more preferably not more than 0.4, % of the acyl groups in the ester mixture are from acid molecules with more than two carboxyl groups each; and either (d)(1) a total of at least 20, or, with increasing preference in the order given, at least 29, 35, or 41% of the acyl groups in the mixture are from one of the trimethylhexanoic acids, most preferably from 3,5,5-trimethylhexanoic acid; and not more than 7.5, or, with increasing preference in the order given, not more than 6.0, 4.5, 3.0, 1.7, 0.9, or 0.4% of the acyl groups in the acid mixture are from dibasic acids; or (d)(2) at least 2.0, or with increasing preference in the order given, at least 2.8, 3.6, 4.1, or 4.9, %, but not more than 13%, preferably not more than 10%, or still more preferably not more than 7.0%, of the acyl groups in the ester mixture are from dibasic acid molecules; and a total of at least 82, or with increasing preference in the order given, at least 85, 89, 93, 96, or 99% of the monobasic acyl groups in the acid mixture have either five or six, or more preferably exactly five, carbon atoms each. In all these percentages, acyl groups are counted as a single group, irrespective of the number of valences they have. For example, each molecule of adipic acid yields a single, dibasic, acyl group when completely esterified.
[0010] (Of course, for all the types of esters described herein as part of the invention, it is possible to obtain the same esters or mixture of esters by reacting acid derivatives such as acid anhydrides, acyl chlorides, and esters of the acids with lower molecular weight alcohols than those desired in the ester products according to this invention, instead of reacting the acids themselves. The acids are generally preferred for economy and are normally specified herein, but it is to be understood that the esters defined herein by reaction with acids can be equally well obtained by reaction of alcohols with the corresponding acid derivatives, or even by other reactions. The only, critical feature is the mixture of acyl groups and alcohol moieties in the final mixture of esters formed.)
[0011] Preferably, with increasing preference in the order given, at least 60, 75, 85, 90, 95, or 98% of the hydroxyl groups in the mixture of alcohols reacted to make esters according to this invention are moieties of PE molecules. Independently, in the mixtures reacted to make the esters according to this invention, with increasing preference in the order given, at least 60, 75, 85, 90, 95, or 98% of the monobasic acid molecules in the acid mixture consist of molecules having no more than ten carbon atoms each and, with increasing preference in the order given, at least 60, 75, 85, 90, 95, or 98% of the dibasic acid molecules in the acid mixture consist of molecules having no more than ten carbon atoms each, or more preferably from five to seven carbon atoms each. Most preferably, with increasing preference in the order given, at least 60, 75, 85, 90, 95, or 98% of the monobasic acid molecules in the acid mixture consist of molecules having either five or nine carbon atoms each.
[0012] These preferences for the acyl groups and alcohol moieties in esters according to this invention are based on empirically determined generalizations. In order to achieve the desired middle range of viscosity, corresponding approximately to ISO grades 22-46, it is advantageous to have a substantial fraction of alcohols with at least four hydroxyl groups. Among the commercially available hindered alcohols that satisfy this criterion, PE is less expensive than DTMP and is free from the ether linkage in DTMP, which increases the hygroscopicity of the esters formed and thereby may promote undesirable corrosion of the metal surfaces lubricated. Alcohols with more than four hydroxyl groups produce esters with higher than optimum viscosities, but some such esters can be tolerated, and mixtures including them may be cheaper. Commercial grade PE often contains a substantial amount of DPE, and costs at least a little less than more purified PE. When cost factors are not severely constraining, removing most or all of the DPE from a predominantly PE mixture of alcohols used to make the esters is preferable, in order to minimize the chance of insolubility of part of the ester mixture at low temperatures.
[0013] In order to obtain esters with adequate viscosity, a considerable fraction of the acid molecules reacted need to have eight or more carbon atoms or be dibasic. Dibasic acids are less desirable. They must be used, if at all, in rather small amounts in order to avoid excessive viscosity, because of the capability of forming very high molecular weight and very viscous oligomers or polymers by reaction between alcohol and acid molecules that both have at least two functional groups. In practice, it has been found that the amount of dibasic acid that can be effectively used in the acid mixture reacted to make esters according to this invention is substantially less than the amount that would be sufficient to provide at least one dibasic acid group to link each two alcohol molecules in the alcohol mixture also reacted. Therefore, when such amounts of dibasic acid are used, some of the alcohol molecules will be joined together in the esters formed and some will not; the esters with two or more alcohol moieties will be much more viscous and normally less readily soluble in the fluorocarbon refrigerant fluids than the other esters in the mixture, those with only one alcohol moiety, thereby increasing the risk of undesirable phase separation in the course of use of the esters. However, limited amounts of dibasic acid may nevertheless be used, as already noted above.
[0014] When substantially only monobasic acids are used to make the esters, as already noted, in order to obtain adequate viscosity in the mixture, a substantial fraction of the acid molecules must have at least eight carbon atoms. With acids of such length, solubility in the fluorocarbon refrigerant fluids is less than for esters with shorter acids, and this reduced solubility is particularly marked for straight chain acids, so that a substantial fraction of the longer acids normally needs to be branched; alternatively, it has been found that these longer straight chain acids can be “balanced” for solubility with an equal or not too much less than equal fraction of branched acids with five or six carbon atoms. When the number of carbon atoms per molecule is nine or more, not even branching is sufficient to produce adequate solubility by itself, so that an upper limit on the fraction of such acids is independently required. In general, a minimum amount of the particularly advantageous i-C 5 acid is specified to aid in solubilizing the parts of the esters in the mixture that contain dibasic acids or those with eight or more carbon atoms.
[0015] For both performance and economic reasons, it has been found that five and nine carbon monobasic acids are the most preferred constituents, and they are very effective in balancing each other to achieve a mix of viscosity and solubility characteristics that is better suited than others to most applications. Trimethylhexanoic acids, with their three methyl branches, produce the most soluble esters among the readily available nine carbon acids. (In general, methyl branches are the most effective in promoting solubility without increasing viscosity excessively, because of the larger number of carbon atoms in other branching groups.) Branches on the carbon alpha to the carboxyl increase the difficulty of esterification and do not appear to be any more effective in increasing solubility than more remotely located branches. The most economical commercially available mixture of branched nine carbon acids, which contains from 88-95 mole % of 3,5,5-trimethylhexanoic acid with all but at most 1 mole % of the remainder being other branched C 9 monobasic acids, appears at least as effective as any other and is therefore preferred for economic reasons as the source of C 9 monobasic acids.
[0016] It is to be understood that only the desired alcohols and acids are explicitly specified, but some amount of the sort of impurities normally present in commercial or industrial grade products can be tolerated in most cases. For example, commercial pentaerythritol normally contains only about 85-90 mole % of pure pentaerythritol, along with 10-15 mole t of di-pentaerythritol, and commercial pentaerythritol is satisfactory for use in making lubricant esters according to this invention in many cases. In general, however, it is preferred, with increasing preference in the order given, that not more than 25, 21, 17, 12, 8, 5, 3, 2, 1, 0.5, or 0.2% of either the hydroxyl groups in the alcohol mixtures specified herein or of the carboxyl groups in the acid mixtures specified herein should be part of any molecules other than those explicitly specified for each type of lubricant base stock. Percentages of specific chemical molecules or moieties specified herein, such as the percentages of carboxyl and hydroxyl groups stated in the preceding sentence, are to be understood as number percentages, which will be mathematically identical to percentages by chemical equivalents, with Avogadro's number of each specified chemical moiety regarded as a single chemical equivalent.
[0017] The above descriptions for each of the acid and alcohol mixtures reacted to produce lubricant esters according to this invention refers only to the mixture of acids or alcohols that actually reacts to form esters and does not necessarily imply that the mixtures of acids or alcohols contacted with each other for the purpose of reaction will have the same composition as the mixture that actually reacts. In fact, it has been found that reaction between the alcohol(s) and the acid(s) used proceeds more effectively if the quantity of acid charged to the reaction mixture initially is enough to provide an excess of 10-25% of equivalents of acid over the equivalents of alcohol reacted with the acid. (An equivalent of acid is defined for the purposes of this specification as the amount containing one gram equivalent weight of carboxyl groups, while an equivalent of alcohol is the amount containing one gram equivalent weight of hydroxyl groups.) The composition of the mixture of acids that actually reacted can be determined by analysis of the product ester mixture for its acyl group content.
[0018] In making most or all of the esters and mixtures of esters preferred according to this invention, the acid(s) reacted will be lower boiling than the alcohol(s) reacted and the product ester(s). When this condition obtains, it is preferred to remove the bulk of any excess acid remaining at the end of the esterification reaction by distillation, most preferably at a low pressure such as 1-5 torr.
[0019] After such vacuum distillation, the product is often ready for use as a lubricant or lubricant base stock according to this invention. If further refinement of the product is desired, the content of free acid in the product after the first vacuum distillation may be further reduced by treatment with epoxy esters as taught in U.S. Pat. No. 3,485,754 or by neutralization with any suitable alkaline material such as lime, alkali metal hydroxide, or alkali metal carbonates. If treatment with epoxy esters is used, excess epoxy ester may be removed by a second distillation under very low pressure, while the products of reaction between the epoxy ester and residual acid may be left behind in the product without harm. If neutralization with alkali is used as the refinement method, subsequent washing with water, to remove any unreacted excess alkali and the small amount of soap formed from the excess fatty acid neutralized by the alkali, is strongly preferred before using the product as a lubricant and/or base stock according to this invention.
[0020] Under some conditions of use, the ester(s) as described herein will function satisfactorily as complete lubricants. It is generally preferable, however, for a complete lubricant to contain other materials generally denoted in the art as additives, such as oxidation resistance and thermal stability improvers, corrosion inhibitors, metal deactivators, lubricity additives, viscosity index improvers, pour and/or floc point depressants, detergents, dispersants, antifoaming agents, anti-wear agents, and extreme pressure resistant additives. Many additives are multifunctional. For example, certain additives may impart both anti-wear and extreme pressure resistance properties, or function both as a metal deactivator and a corrosion inhibitor. Cumulatively, all additives preferably do not exceed 8% by weight, or more preferably do not exceed 5% by weight, of the total compounded lubricant formulation.
[0021] An effective amount of the foregoing additive types is generally in the range from 0.01 to 5% for the anti-oxidant component, 0.01 to 5% for the corrosion inhibitor component, from 0.001 to 0.5% for the metal deactivator component, from 0.5 to 5% for the lubricity additives, from 0.01 to 2% for each of the viscosity index improvers and pour and/or floc point depressants, from 0.1 to 5% for each of the detergents and dispersants, from 0.001 to 0.1% for anti-foam agents, and from 0.1-2% for each of the anti-wear and extreme pressure resistance components. All these percentages are by weight and are based on the total lubricant composition. It is to be understood that more or less than the stated amounts of additives may be more suitable to particular circumstances, and that a single molecular type or a mixture of types may be used for each type of additive component. Also, the examples listed below are intended to be merely illustrative and not limiting, except as described in the appended claims.
[0022] Examples of suitable oxidation resistance and thermal stability improvers are diphenyl-, dinaphthyl-, and phenylnaphthyl-amines, in which the phenyl and naphthyl groups can be substituted, e.g., N,N′-diphenyl phenylenediamine, p-octyldiphenylamine, p,p-dioctyldiphenylamine, N-phenyl-1-naphthyl amine, N-phenyl-2-naphthyl amine, N-(p-dodecyl)phenyl-2-naphthyl amine, di-1-naphthylamine, and di-2-naphthylamine; phenothazines such as N-alkylphenothiazines; imino(bisbenzyl); and hindered phenols such as 6-(t-butyl) phenol, 2,6-di-(t-butyl) phenol, 4-methyl-2,6-di-(t-butyl) phenol, 4,4′-methylenebis(-2,6-di-{t-butyl} phenol), and the like.
[0023] Examples of suitable cuprous metal deactivators are imidazole, benzamidazole, 2-mercaptobenzthiazole, 2,5-di-mercaptothiadiazole, salicylidine-propylenediamine, pyrazole, benzotriazole, tolutriazole, 2-methylbenzamidazole, 3,5-dimethyl pyrazole, and methylene bis-benzotriazole. Benzotriazole derivatives are preferred. Other examples of more general metal deactivators and/or corrosion inhibitors include organic acids and their esters, metal salts, and anhydrides, e.g., N-oleyl-sarcosine, sorbitan monooleate, lead naphthenate, dodecenyl-succinic acid and its partial esters and amides, and 4-nonylphenoxy acetic acid; primary, secondary, and tertiary aliphatic and cycloaliphatic amines and amine salts of organic and inorganic acids, e.g., oil-soluble alkylammonium carboxylates; heterocyclic nitrogen containing compounds, e.g., thiadiazoles, substituted imidazolines, and oxazolines; quinolines, quinones, and anthraquinones; propyl gallate; barium dinonyl naphthalene sulfonate; ester and amide derivatives of alkenyl succinic anhydrides or acids, dithiocarbamates, dithiophosphates; amine salts of alkyl acid phosphates and their derivatives.
[0024] Examples of suitable lubricity additives include long chain derivatives of fatty acids and natural oils, such as esters, amines, amides, imidazolines, and borates.
[0025] Examples of suitable viscosity index improvers include polymethacrylates, copolymers of vinyl pyrrolidone and methacrylates, polybutenes, and styrene-acrylate copolymers.
[0026] Examples of suitable pour point and/or floc point depressants include polymethacrylates such as methacrylateethylene-vinyl acetate terpolymers; alkylated naphthalene derivatives; and products of Friedel-Crafts catalyzed condensation of urea with naphthalene or phenols.
[0027] Examples of suitable detergents and/or dispersants include polybutenylsuccinic acid amides; polybutenyl phosphonic acid derivatives; long chain alkyl substituted aromatic sulfonic acids and their salts; and metal salts of alkyl sulfides, of alkyl phenols, and of condensation products of alkyl phenols and aldehydes.
[0028] Examples of suitable anti-foam agents include silicone polymers and some acrylates.
[0029] Examples of suitable anti-wear and extreme pressure resistance agents include sulfurized fatty acids and fatty acid esters, such as sulfurized octyl tallate; sulfurized terpenes; sulfurized olefins; organopolysulfides; organo phosphorus derivatives including amine phosphates, alkyl acid phosphates, dialkyl phosphates, aminedithiophosphates, trialkyl and triaryl phosphorothionates, trialkyl and triaryl phosphines, and dialkylphosphites, e.g., amine salts of phosphoric acid monohexyl ester, amine salts of dinonylnaphthalene sulfonate, triphenyl phosphate, trinaphthyl phosphate, diphenyl cresyl and dicresyl phenyl phosphates, naphthyl diphenyl phosphate, triphenylphosphorothionate; dithiocarbamates, such as an antimony dialkyl dithiocarbamate; chlorinated and/or fluorinated hydrocarbons, and xanthates.
[0030] Under some conditions of operation, it is believed that the presence in lubricants of the types of polyether polyols that have been prominent constituents of most prior art lubricant base stocks taught as useful with fluorocarbon refrigerant working fluids are less than optimally stable and/or inadequately compatible with some of the most useful lubricant additives. Thus, in one embodiment of this invention, it is preferred that the lubricant base stocks and lubricants be substantially free of such polyether polyols. By “substantially free”, it is meant that the compositions contain no more than about 10% by weight, preferably no more than about 2.6% by weight, and more preferably no more than about 1.2% by weight of the materials noted.
[0031] One major embodiment of the present invention is a refrigerant working fluid comprising both a suitable heat transfer fluid such as a fluorocarbon and a lubricant according to this invention. Preferably, the refrigerant working fluid and the lubricant should have chemical characteristics and be present in such a proportion to each other that the working fluid remains homogeneous, i.e., free from visually detectable phase separations or turbidity, over the entire range of working temperatures to which the working fluid is exposed during operation of a refrigeration system in which the working fluid is used. This working range may vary from −60° C. to as much as +175° C. It is often adequate if the working fluid remains single phase up to +30° C., although it is increasingly more preferable if the single phase behavior is maintained up to 40, 56, 71, 88, or 100° C. Similarly, it is often adequate if the working fluid compositions remains a single phase when chilled to 0° C., although it is increasingly more preferable if the single phase behavior persists to −10, −20, −30, −40, or −55° C. Single phase mixtures with chlorine free hydrofluorocarbon refrigerant working fluids are usually obtained with the suitable and preferred types of esters described above.
[0032] Inasmuch as it is often difficult to predict exactly how much lubricant will be mixed with the heat transfer fluid to form a working fluid, it is most preferable if the lubricant composition forms a single phase in all proportions with the heat transfer fluid over the temperature ranges noted above. This however, is a very stringent requirement, and it is often sufficient if there is single phase behavior over the entire temperature range for a working fluid mixture containing up to 1% by weight of lubricant according to this invention. Single phase behavior over a temperature range for mixtures containing up to 2, 4, 10, and 15% by weight of lubricant is successively more preferable.
[0033] In some cases, single phase behavior is not required. The term “miscible” is used in the refrigeration lubrication art and hereinafter, except when part of the phrase “miscible in all proportions”, when two phases are formed but are readily capable of being mixed into a uniform dispersion that remains stable as long as it is at least moderately agitated mechanically. Some refrigeration (and other) compressors are designed to operate satisfactorily with such miscible mixtures of refrigerant working fluid and lubricant. In contrast, mixtures that lead to coagulation or significant thickening and form two or more phases are unacceptable commercially and are designated herein as “immiscible”. Any such mixture described below is a comparative example and not an embodiment of the present invention.
[0034] Another major embodiment of the invention is the use of a lubricant according to the invention, either as total lubricant or lubricant base stock, in a process of operating refrigerating machinery in such a manner that the lubricant is in contact with the refrigerant working fluid.
[0035] The practice of the invention may be further understood and appreciated by consideration of the following examples and comparative examples.
[0036] General Ester Synthesis Procedure
[0037] The alcohol(s) and acid(s) to be reacted, together with a suitable catalyst such as dibutyltin diacetate, tin oxalate, phosphoric acid, and/or tetrabutyl titanate, were charged into a round bottomed flask equipped with a stirrer, thermometer, nitrogen sparging means, condenser, and a recycle trap. Acid(s) were charged in about a 15% molar excess over the alcohol(s). The amount of catalyst was from 0.02 to 0.1% by weight of the weight of the total acid(s) and alcohol(s) reacted.
[0038] The reaction mixture was heated to a temperature between about 220 and 230° C., and water from the resulting reaction was collected in the trap while refluxing acids were returned to the reaction mixture. Partial vacuum was maintained above the reaction mixture as necessary to achieve a reflux rate of between 8 and 12% of the original reaction mixture volume per hour.
[0039] The reaction mixture was sampled occasionally for determination of hydroxyl number, and after the hydroxyl number had fallen below 5.0 mg of KOH per gram of mixture, the majority of the excess acid was removed by distillation after applying the highest vacuum obtainable with the apparatus used, corresponding to a residual pressure of about 0.05 torr, while maintaining the reaction temperature. The reaction mixture was then cooled, and any residual acidity was removed, if desired, by treatment with lime, sodium hydroxide, or epoxy esters. The resulting lubricant or lubricant base stock was dried and filtered before phase compatibility testing.
[0040] General Procedure for Phase Compatibility Testing
[0041] One milliliter (“ml”) of the lubricant to be tested is placed into a thermal shock resistant, volumetrically graduated glass test tube 17 millimeters (“mm”) in diameter and 145 mm long. The test tube is then stoppered and placed into a cooling bath regulated to −29±0.2° C. After the tube and contents have equilibrated in the cooling bath for 5 minutes (“min”), sufficient refrigerant working fluid is added to give a total volume of 10 ml.
[0042] At least 15 min after the working fluid has been added, during which time the tube and contents have been equilibrating in the cooling bath and the contents may have been agitated if desired, the tube contents are visually examined for evidence of phase separation. If there is any such phase separation, the tube is shaken to determine whether the combination can be rated as miscible or is totally unacceptable.
[0043] If there is no evidence of phase separation at −29° C., the temperature of the cooling bath is usually lowered at a rate of 0.3° per min until phase separation is observed. The temperature of first observation of phase separation, if within the range of the cooling equipment used, is then noted as the insolubility onset temperature.
[0044] Composition of Specific Examples
[0045] A suitable ester mixture as described above was prepared by reacting a mixture of alcohol molecules in which 99.4% were PE molecules, with most of the remainder being DPE molecules, with a mixture of acid molecules that included 46.7% of pentanoic (=n-valeric) acid, 21.5% of 2-methylbutanoic acid, and 31.6% of 3,5,5-trimethylhexanoic acid, with the remainder predominantly other branched C 9 monobasic acids. This ester mixture had an ISO grade of 32.
[0046] A second suitable ester mixture as described above was prepared by reacting a mixture of alcohol molecules in which 99.4% were PE molecules, with most of the remainder being DPE molecules, with a mixture of acid molecules that included 66.8% of pentanoic (=n-valeric) acid, 28.4% of 2-methylbutanoic acid, and 4.6% of adipic acid, with the remainder being predominantly 3-methylbutanoic acid. This lubricant base stock had an ISO grade of 32. | A high quality lubricant for hermetically sealed domestic air conditioner and refrigerator compressors, especially those using chlorine free hydrofluorocarbon refrigerant working fluids, is provided by mixed esters of hindered polyols, most desirably pentaerythritol, with a mixture of carboxylic acids including at least some iso-pentanoic acid along with either or both of iso-nonanoic acid and dibasic acids such as adipic. | 2 |
FIELD OF INVENTION
The present invention relates to “active implantable medical devices” as such devices are defined by the Jun. 20, 1990 directive 90/385/CEE of the Council of the European Communities, and more particularly to cardiac pacemaker, defibrillator and/or cardiovertor devices, including multisite cardiac stimulation devices, that are able to deliver to the heart stimulation pulses of low energy for the treatment of cardiac rhythm disorders.
BACKGROUND OF THE INVENTION
It is known from, for example, in the EP-A-0 970 713 and its corresponding U.S. Pat. No. 6,574,507 B1, commonly assigned herewith to ELA Medical S.A. Montrouge, France, to diagnose and treat respiratory disorders such as the apnea revealing a pathology known as “sleep apnea syndrome” (SAS). In a general manner, this SAS respiratory pathology is characterized by the frequent occurrence of apnea during a phase of sleep of the patient (e.g., at least 10 to 20 events per hour). An “apnea” (also known as a respiratory pause) is defined as a temporary cessation (or stop) of the respiratory function of a duration that is greater than approximately 10 seconds. The SAS pathology also can be characterized by the occurrence of hypopnea under the same frequency conditions. A “hypopnea” is defined as a significant decrease (but without interruption) of the respiratory flow, typically a decrease of more than 50% as compared to a previously acquired respiratory flow reference.
The interruption or the reduction of the respiratory flow involves a reduction in the oxygen concentration of blood (also known as the oxygen saturation), and the occurrence of unconscious, micro waking-up events. This pathology, which is found in more than 50% of those patients patients suffering from a cardiac insufficiency condition, has as a consequence inter alia a diurnal somnolence, a loss of attention, an increase in the risks of road (automobile) accidents, and a higher incidence of hypertension.
The above mentioned EP-A-0 970 713 and U.S. Pat. No. 6,574,507 B1 discloses apparatus and methods for diagnosing the occurrence of an apnea from a minute-ventilation signal (“signal VE,” also designated as “signal Mv”), which is a parameter of physiological preponderance generally obtained by a measurement of intrathoracic impedance. The signal MV provides a continuous indication of the respiration rate and the respiratory flow volume of the patient. If an apnea occurs during a phase (also called a “state”) of sleep of the patient (the sleep state of the patient can be, for example, indicated by an activity sensor of physical preponderance such as an accelerometer), then the device delivers a cardiac stimulation at a frequency that is slightly higher than the natural sinusal rate/rhythm of the patient. This increased frequency is provided to increase the blood flow in order to be able to reduce the incidence of the oxygen desaturation caused by a SAS.
The starting point of this invention lies in the observation by the inventors that a systematic increase of the heart rate in response to a detection of apnea or hypopnea is not always a suitable treatment. Indeed, it has been reported that for certain patients the apnea or hypopnea could be followed by an adrenergic reaction. Such a reaction naturally induces a light tachycardia and a significant increase in blood pressure, sufficient to compensate for the fall of the ventilatory activity. Among these patients, the myocardium thus can react naturally by adapting its contractility so as to increase the blood flow. In this way, the myocardium maintains the blood appreciably at the same level of oxygen saturation.
Ideally, to decide whether or not it is necessary to apply to the myocardium a stimulation at a frequency higher than the natural sinusal rate/rhythm of the patient, the best criterion would be a direct measurement of oxygen saturation in blood. Then, the stimulation would be started only in the event of a proven and significant desaturation. But such a direct measurement of oxygen saturation is difficult to implement in a simple and permanent manner in the context of an active implanted medical device, given the current state of the art.
OBJECTS AND SUMMARY OF THE INVENTION
Broadly, the present invention proposes to overcome the aforementioned deficiency in the treatment of the apnea and the hypopnea by estimating variation of contractility of the myocardium by use of an hemodynamic sensor. Thus, in the event of a detected anomaly in the respiratory activity (i.e., an apnea or hypopnea), before taking any therapeutic action, the device estimates whether or not there was a correlative modification of the myocardium contractility:
1. If the hemodynamic sensor indicates the occurrence of a notable hemodynamic fall, revealing that the myocardium could not naturally adapt its contractility following the anomaly, or did not adapt sufficiently, then the device takes an action in order to compensate for the oxygen desaturation induced by the respiratory disorder. For example, if the hemodynamic fall and associated inadequate myocardium contractility follows an apnea or an hypopnea, then a stimulation is triggered at a frequency that is higher than the natural sinusal rate/rhythm.
2. In the contrary case, i.e., if the hemodynamic sensor delivers a signal indicative of stable or not very evolutionary hemodynamic information, the device does not take an action, because this situation probably reveals that there no was desaturation requiring a recovery by an increase of the blood flow.
In other words, the invention proposes, in the event of a detected respiratory anomaly, to adapt the reaction of the device according to the stabilization of the hemodynamic information, which provides an estimate of the variations of contractility, correlated to the increases in blood pressure. It is noted that the analysis of hemodynamic information can be based on hemodynamic information collected (sensed) before or after the respiratory anomaly.
One aspect of the present invention is therefore directed to a device of the type that is described by the above mentioned EP A 0 970 713 and corresponding U.S. Pat. No. 6,574,507 B1, i.e., an implantable medical device that includes circuit structure and functionality able to measure the respiratory activity and deliver a signal representative of ventilatory activity of the patient, and circuit means for analyzing the ventilatory activity signal to detect the occurrence of a respiratory apnea, a respiratory hypopnea or both.
In accordance with the present invention, the device also includes a hemodynamic sensor that is able to deliver a hemodynamic signal that is representative of the contractility of the myocardium, and circuit means for analyzing the delivered hemodynamic signal and detecting an occurrence of a variation of the myocardium contractility, and means for conditionally modifying an operating parameter of the device in the event of a detected hemodynamic state variation in relation to the detection of an apnea or of a hypopnea (either before or following the detection). In other words, the detection of the variation of the detected hemodynamic state can be performed equally as well after as before the detection of the apnea or the hypopnea. In this regard, the device requires a period of time to declare, e.g., an apnea, such as 10 seconds. During this time, the hemodynamic signal has significantly decreased. Thus, it is possible to respond to the decrease and begin accelerating the pacing to compensate for the fall before the “official” detection of an apnea.
Preferably, hemodynamic sensor includes circuits for measuring an intracardiac impedance, or a sensor for measuring an endocardial acceleration.
Preferably, the conditionally modification means operates to modify in a temporary manner an operating parameter of the device, and then restore this same operating parameter to its previously set value when the analysis of the delivered hemodynamic signal no longer detects any variation of the hemodynamic state. The operating parameter of the device that is conditionally modified can be selected from among the following:
1. The stimulation frequency, where the frequency is increased in the event of a determined variation of the detected hemodynamic state in relation to the detection of an apnea or a hypopnea.
2. The atrio-ventricular delay, wherein the delay is shortened in the event of a determined variation of the detected hemodynamic state in relation to the detection of an apnea or a hypopnea, or
3. For a device including multisite stimulation functionality, the stimulation mode, wherein the means of conditionally modifying means operates to trigger a multisite stimulation in the event of a detected hemodynamic state variation in relation to the detection of an apnea or of a hypopnea. A multisite stimulation mode is known to persons of ordinary skill in the art, as described, for example, in U.S. Pat. No. 6,253,106 B1, which is commonly assigned herewith and the disclosure of which is incorporated herein by reference. A multisite cardiac stimulation device typically includes at least a right and a left ventricular electrode for stimulating the right and left ventricle, as well as a right atrial electrode for delivering an atrial stimulation (and optionally a left atrial electrode for stimulating the left atrium), such that each chamber can be independently stimulated under appropriate control logic implementing known therapies for multisite pacing.
In a preferred embodiment, the hemodynamic signal analyzing means functions to compare the hemodynamic signal measured at the cardiac cycle following the respiratory cycle during which the apnea or hypopnea occurred, with an average of the hemodynamic signals acquired prior to the respiratory cycle during which the apnea or hypopnea occurred.
In another preferred embodiment, the hemodynamic signal analyzing means functions to compare the hemodynamic signal measured after a plurality of cardiac cycles following the respiratory cycle during which the apnea or hypopnea occurred, with an average of the hemodynamic signals acquired prior to the respiratory cycle during which the apnea or hypopnea occurred.
BRIEF DESCRIPTION OF THE DRAWINGS
Further benefits, features and characteristics of the present invention will become apparent to a person of ordinary skill in the art in view of the following detailed description of preferred embodiments of the invention, made with in reference to the annexed drawings, in which:
FIG. 1 is a flowchart of a first embodiment of the invention; and
FIG. 2 is a flow chart of a second embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The device in accordance with the present invention comprises means for detecting an occurrence of apnea or of hypopnea by an analysis of the respiration rate of the patient during his sleep, this rate/rhythm being given by the evolution over the course of the time of the minute ventilation signal (signal MV).
Signal MV is a parameter with physiological preponderance (i.e., predominantly physiological in nature) that is obtained by a measurement of intrathoracic (or intracardiac) impedance. This measurement, in itself well known, is commonly operated between two electrodes laid out in the patient's rib cage, or between an electrode (for example, a stimulation electrode, if the implanted device is a cardiac pacemaker) and the case of the implanted device. The impedance is measured as a voltage in response to an injection of a constant current pulse of a few hundred microamperes, at a frequency of a few Hertz, typically 8 Hz. This technique, for example, is described by Bonnet J L et al., “Measurement of Minute-Ventilation with Different DDDR Pacemaker Electrode Configurations,” PACE , Vol. 21, 98, Part 1, and it is implemented in the Chorus RM 7034 brand pacemaker devices, commercially available from ELA Médical.
In addition, the device comprises means for detecting the phases of sleep of the patient, in order to proceed to the study of the apnea or hypopnea only during the detected sleep phases. This constraint is used because the variations of respiratory activity occurring during a phase of awakening are not normally pathological.
Although the precise manner of detecting a sleep phase is not important to the invention, one suitable technique is to diagnose sleep by using a physiological sensor for measuring the minute ventilation, possibly in combination with a sensor for measuring activity, a parameter having a physical preponderance such as acceleration, as described in the EP-A 0 750 920 and its corresponding U.S. Pat. No. 5,722,996 and EP A-0 770 407 and its corresponding U.S. Pat. No. 5,766,228, each commonly assigned herein to ELA Medical, which U.S. Pat. Nos. 5,722,996 and 5,766,228 are incorporated herein by reference in their entirety.
The device considers that there is apnea when it detects a cessation of respiratory activity of a duration longer than 10 seconds. This is a phenomenon that is simple to detect by monitoring signal MV. To detect hypopnea, the device can, for example, compare different sliding averages of signals MV, which averages are established, for example, over 10 seconds duration. If between two such consecutive averages a significant decrease of the ventilation minute is detected, for example, a decrease of more than 50%, then the device considers that there is hypopnea.
Furthermore, to allow the implementation of the invention, the device comprises an hemodynamic sensor making it possible to estimate the variations of myocardium contractility, which are correlated with the increases in blood pressure. This hemodynamic state parameter is more sensitive and varies more rapidly than the measure of the heart rate variations, to estimate better the consequences of the oxygen desaturation.
The hemodynamic sensor can be in particular an endocardial acceleration sensor of the type PEA (Peak Endocardial Acceleration) as described, for example, in the EP-A 0 515 319 and its corresponding U.S. Pat. No. 5,304,208, EP-A 0 582 162 and its corresponding U.S. Pat. No. 5,454,838, or EP-A 0 655 260 and its corresponding U.S. Pat. No. 5,496,351 (which are assigned to Sorin Biomedica Cardio SpA), and which U.S. patents are incorporated herein by reference in their entirety. A suitable commercial device for measuring heart acceleration is available from Sorin Biomedica Cardio SpA under the trade name Living CHF, and an electrode having an accelerometer at its tip also is available from Sorin under the trade name Best. The hemodynamic sensor can be also a sensor of endocardiac impedance, for example, a sensor of transvalvular bio-impedance, as described by the EP-A 1 116 497 and its corresponding U.S. Pat. No. 6,604,002, or of trans-septum bio-impedance, as described by the EP-A 1 138 346 and its corresponding published U.S. Patent Application US2001/0034540 A1 011029, both in the name of ELA Medical which U.S. patent and publication are incorporated herein by reference in their entirety.
One now will describe more particularly, with reference to the flow chart of FIG. 1 , a first embodiment by which the invention can be implemented. The device, after having awaited the end of a respiratory cycle (stage 10 ), determines whether an apnea or an hypopnea has occurred (stage 12 ), i.e., if it found a cessation of the respiratory cycle of a duration longer than 10 seconds or a fall of the respiratory flow by more than 50%. In the negative case, no action is taken and the device continues to monitor (analyze) the respiration rate (stage 10 ). In the affirmative case, on the other hand, the device analyzes whether or not there were a significant variation of the hemodynamic state consecutive to the detected apnea or this hypopnea (stage 12 ).
To this end, after having awaited the end of the currently running cardiac cycle (stage 14 ), the device determines (stage 16 ) whether the hemodynamic sensor detected a fall of the hemodynamic signal greater than a given reference threshold. This reference threshold is preferably a dynamic threshold made up, for example, by an average, over a plurality of cardiac cycles, of the signal values delivered by the hemodynamic sensor. The average considered is in this embodiment preferably based on values of signals acquired prior to the respiratory cycle presenting the anomaly, i.e., prior to the respiratory cycle detected at the end at stage 10 .
In the event of a demonstrable hemodynamic fall, which one would expect results in a reduction in the oxygen saturation in blood because of the apnea or of the hypopnea, then the device increases the frequency of stimulation by a step (stage 18 ). This small increase in frequency (a step of increase being typically selected from between 1 and 5 bpm) makes it possible to compensate for the oxygen desaturation. In alternative embodiments, or to complement the heart rate, other operating parameters of the pacemaker can be modified: one can thus consider, for example, shortening the AV delay and/or the triggering of a multisite stimulation.
The algorithm is then repeated in the same way as previously. The increase in the stimulation frequency at stage 18 normally results in an improvement of the hemodynamic state of the patient. If this improvement is not sufficient to lead to a stabilization of hemodynamic information, the device will still detect a hemodynamic fall (at stage 16 of the following iteration) and will increase by an additional step the stimulation frequency (at the subsequent stage 18 ).
On the other hand, if the increase in the stimulation frequency, by one or more steps (i.e., after one or more iterations), led to an hemodynamic stabilization of the state, an absence of significant variation of the signal, detected at stage 16 , will lead to a test at stage 20 where the device compares the current stimulation frequency F STIM to a reference frequency F PROG , e.g., a preprogrammed frequency.
If the stimulation frequency F STIM is higher than pre-programmed frequency F PROG , then the device decreases the stimulation frequency by one step (stage 22 ) before returning to the starting point (stage 6 ) of the flow chart. Thus, by successive step adjustments, in increased or decreased directions, the stimulation frequency F STIM could be continuously adjusted to the effective minimum. This in turn makes it possible to obtain a more precise stabilization of the hemodynamic state, without exceeding this value by more than one step.
FIG. 2 illustrates a second embodiment of the present invention, in which the same reference numbers are used for the stages that are the same as the stages described in connection with FIG. 1 . In this alternative embodiment, the device operates the test of stage 16 (same as in FIG. 1 ) on the hemodynamic signal, but not on the cardiac cycle which immediately follows the detected apnea or hypopnea at stage 12 , and rather only after N cardiac cycles following the detected apnea or hypopnea.
For this purpose, the algorithm counts the number of past cycles (stage 24 , counter N) and compares the value of counter N with a programmed value prog (stage 26 ), for example, N=5 cycles (prog=5). Thus, at the start (stage 8 ), the count value N is reset to equal to zero. This embodiment is believed to make it possible for an adrenergic reaction, suitable to induce a significant modification of the hemodynamic state, to express itself naturally without need for taking a therapeutic action.
It should be understood that the test for the sleep state (stage 8 ), illustrated in FIGS. 1 and 2 as outside of the monitoring of the respiratory cycle, equally may be located within the monitoring of the respiratory cycle, as a matter of design choice. Preferably, the patient is known to be in a sleep phase when the present invention is being used.
Suitable devices for which the present invention has application include, for example, the active implantable medical devices available from Ela Médical, Montrouge France. These devices are microprocessor-based systems having circuits for receiving, conditioning and processing detected electrical signals, and that are capable of receiving software instructions by telemetry, storing them in memory, and then executing those instructions to perform the functions described above in implementing the present invention. The creation of suitable software instructions for controlling an implant to perform the aforementioned functions of the present invention are believed to be within the abilities of a person of ordinary skill in the art. The detection circuits used to detect the cardiac signals in the atrium and the ventricle, in the left and/or right chambers, are well known and any suitable design may be used. The circuits used to inject the currents to obtain the bioimpedance measurements are known as well from, for example, EP 1 116 497 and corresponding U.S. Pat. No. 6,604,002 B1 and EP 1 138 346 and corresponding U.S. Published Pat. Application 2001-0034540, and any suitable circuit to may be used. The activity sensor used and the determination of rest phases might be taken from the devices disclosed in, for example, U.S. Pat. No. 5,722,996 and EP1317943 and its corresponding U.S. Published Patent Application 2003-0163059, which disclosures are incorporated herein by reference.
One skilled in the art will appreciate that the present invention can be practiced by other than the described embodiments, which are presented for purposes of illustration and not of limitation. | Improved management of respiratory pauses (apnea) or hypopnea in an active implantable medical device of the cardiac pacemaker, cardiovertor and defibrillator types including multisite devices. This device operates to analyze the patient's respiratory activity, detect the occurrence of respiratory pauses (apnea) or diminutions (hypopnea), analyze the contractility of the myocardium, for example, by measurement of the intracardiac impedance or the endocardial acceleration, and detect the occurrence of a variation of the hemodynamic state. In the event of a significant variation of the hemodynamic state (i.e., contractility) detected in relation to the detection of an apnea or of an hypopnea, the device modifies conditionally and temporarily an operating parameter of the device, for example, the frequency of stimulation, the atrio-ventricular delay or to trigger a multistate stimulation to compensate. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This applications claims the benefit under 35 USC 119(e) of prior U.S. provisional application No. 60/638,389, filed Dec. 27, 2004, the contents of which are herein incorporated by reference.
FIELD OF THE INVENTION
[0002] This invention relates to content-routed networks, and in particular to a method of data logging in content-routed networks.
BACKGROUND OF THE INVENTION
[0003] Content-based networks are described in A Carzaniga, M. J. Rutherford, A. L. Wolf, A routing scheme for content-based networking, Department of Computer Science, University of Colorado, June 2003, the contents of which are incorporated herein by reference.
[0004] In content routed networks, a publish/subscribe data communication is provided; wherein publishers can inject content into the network, and subscribers can subscribe to content from the network. The publishers and subscribers do not require knowledge of each other.
[0005] FIG. 1 depicts an example content-routed network 1 , which consists of a plurality of content routers 2 , 3 , 4 , and 5 interconnected by links 11 , 12 , 15 and 16 ; a publisher 6 (note that a content routed network typically will have a plurality of publishers but only one is shown in FIG. 1 ); a plurality of subscribers 7 , 8 , 9 and 17 (note that a content routed network can contain a large number of subscribers, i.e. millions). A publisher is a computer or user that can insert content into the network. A subscriber is a computer or user who has expressed interest in some specific content. Publisher 6 publishes a document into the content routed network by sending it over link 10 to content router 2 . Content router 2 matches the content of the received document against the subscriptions for the network, which the router learned of through a content routing protocol (refer to co-filed application Ser. No. 11/012,113, the contents of which are incorporated herein by reference) or by some other means. Content router 2 determines that the document is required by a local subscriber on content router 2 , and one or more subscribers on content router 3 and content router 4 , but not by any subscribers on content router 5 . As a result, a single copy of the document is sent over link 11 to content router 3 , since link 11 is the preferred path to content routers 3 and 4 in this example. In addition, a copy of the document is sent over link 18 to local subscriber 17 . Content router 3 delivers the document to all local subscribers which have matching subscriptions, which in this case is subscriber 7 . So, a copy of the document is sent over link 13 to subscriber 7 . In addition, the document is forwarded on to content router 4 over link 12 . In a similar manner, content router 4 delivers the document to any local subscribers with matching subscriptions, which in this case is subscriber 8 . Thus, the document is sent over link 14 to subscriber 8 . Content router 4 also determines that no further content routers require a copy of the document. For full details of the content routing protocol-used, reference is made to U.S. patent application Ser. No. 11/012,113.
[0006] When content routing techniques are applied to the wide area network, such as being deployed in a service provider network, new capabilities are required as opposed to deployment scenarios within an enterprise (known as an Enterprise Service Bus; ESB). A service provider, such as a regional, national or international telecommunication provider, can provide network-resident content routing capability to provide an Extended Enterprise Service Bus (EESB). Such a deployment introduces new requirements onto the content-routed network, such as the requirement to provide data logging facilities for the purpose of billing, performance monitoring, troubleshooting, and security logging. Note also that data collection is also useful for content routing within an enterprise, for example, to be able to bill various departments of the enterprise based on network usage, or to troubleshoot problems, etc.
SUMMARY OF THE INVENTION
[0007] According to the present invention there is provided a method of managing a content routed network, comprising distributing published documents through said network for delivery to subscribers; storing data logs pertaining to said published documents at different points in the network; and correlating said data logs stored at said different points to obtain information about the operation of said network.
[0008] It will be understood that the term document is used in the most general sense in this application and includes any entity containing content, including multimedia content, capable of being published and delivered to subscribers. Another term for document is message.
[0009] Embodiments of the invention can provide the capability to be able to provide flexible billing schemes within a content routed network, such as billing a publisher based on the quantity of documents published or the volume of data published, billing a subscriber based on the quantity of documents received or the volume of data received; billing a publisher based on the quantity of documents or volume of data delivered to subscribers in the content routed network, the capability to bill based on the type of document being published or delivered, etc.
[0010] Embodiments of the invention can provide the capability to measure quality of service within the content routed network, such as the latency of document delivery from the time of publishing to the time of delivery. Latency can also be measured across the group of subscribers receiving a particular document to ensure that delivery across the group of subscribers is fair. For example, for the dissemination of real-time data such as stock quotes, each subscriber should receive the information within a bounded amount of time of each other, as dictated by a service level agreement.
[0011] Embodiments of the invention can provide the capability required to be able to prove or audit delivery of documents to subscribers in order to demonstrate lossless delivery within a specified service level agreement (SLA), for example.
[0012] Embodiments of the invention can provide the capability to log events, such as lack of document delivery, document rejection due to encoding or formatting errors, rejected documents due to lack of entitlement, etc. in order to provide measurement of such events and to provide data logs for troubleshooting.
[0013] Embodiments of the invention can also provide data logging of documents being published and delivered, including a correlation of which published documents have been delivered to which subscribers, for security logs.
[0014] Embodiments of the invention can also provide data logging to track “self serve” publisher/subscriber activity for the purposes of billing or troubleshooting. Logging information about subscribers adding or deleting subscriptions or filters is an example of this type of “self serve” activity.
[0015] Embodiments of the invention allow logging information for each document published to be correlated with separate records recorded elsewhere in the network for each document delivered. A per-document network-wide unique tag (preferentially globally unique) may used for correlating publish and delivery records. Documents may be timestamped at the publishing point in the network, and this time output in the publishing record; similarly, timestamping and outputting a record at each delivery point (requires use of synchronized networks clocks such as from NTP). This provides the ability to correlate publish and subscriber records (via the unique tag above), and then use the timestamps to determine the delivery latency for each subscriber, and among the set of subscribers. This can be used for service-level agreement monitoring.
[0016] Embodiments of the invention can offer the ability to bill on volume of data published, number of documents published (to the publisher), volume of data or number of bytes received (billable to the end subscriber, or to the publisher, or both), in addition to time of day-billing structures etc. Also, records can be output for error conditions, such as documents rejected due to XML errors, firewall restrictions, etc., and integrated into an overall data collection system.
[0017] Embodiments of the invention offer control over what data is output. Also, it is possible just to output summary data on a timed basis, such as 15-minute aggregate records for very high-volume conditions such as market data. In that case, a hybrid method can be employed such that some small % of documents still also have a detailed record emitted at publishing points and each delivery point such that latency can be measured on a sampled basis.
[0018] It is possible to control whether to output a record and the type of record to output based on the configuration of filters (Xpath Expressions (XME) in the case of XML networks) that, when matched, triggers the emission of a data logging record of a certain type. This can be used to override the default logging (e.g. summary) depending on the document content.
[0019] The ability to include information in the logging record based on the content of the document, as indicated by a content match (using an XPE in the case of XML networks).
[0020] Embodiments of the invention allow the publisher to supply a parameter that is logged by router (“userData”). This tag is carried thru the network and delivered to the subscriber. This allows correlation of publisher, router and subscriber logs to validate end-to-end delivery of the document, as well as network latency calculation.
[0021] Since embodiments of the invention employ a generic XML-encoded capture mechanism, the ability to capture other “events” in the network such as subscription add/delete activity on a per-sub basis when subscriber-self-serve is supported.
[0022] A distinction is made between the time that a document could have been delivered to a subscriber (i.e. when it was available for delivery), vs. the time when it was actually delivered so it is possible to differentiate between the two events when a document cannot be delivered right away to a subscriber (e.g. when a subscriber is offline).
[0023] The “code” associated with a subscription that he has registered (in addition to using the code in the log records) may also be provided to the subscriber.
[0024] In another aspect the invention provides a content routed network comprising a plurality of content routers, each content router comprising a central processing unit; a first memory portion storing programs and data; and a second memory portion storing log records of published content passing through the content router.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings, in which:
[0026] FIG. 1 shows an example content routed network;
[0027] FIG. 2 shows a content router;
[0028] FIG. 3 shows data logging processing;
[0029] FIG. 4 shows an example ingress record;
[0030] FIG. 5 shows an example egress record;
[0031] FIG. 6 shows an example traffic log file;
[0032] FIG. 7 shows an example ingress data logging filter table;
[0033] FIG. 8 shows an example egress data logging filter table;
[0034] FIG. 9 shows an example subscription record;
[0035] FIG. 10 shows an example summary ingress record;
[0036] FIG. 11 shows an example summary egress record; and
[0037] FIG. 12 shows data logging between networks of different administrative domains.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0038] In example content routed network 1 of FIG. 1 , data logs are produced for each published document. For example, for each document published into network 1 by publisher 6 , the ingress content router 2 produces an ingress data record 19 to record relevant information about the document being published. Similarly, data logs are produced for each document sent to a subscriber. In network 1 , when an egress content router, such as 3 , delivers a document to subscriber 7 , content router 3 produces an egress data record 21 to record relevant information about the delivered document. Similarly, content router 4 produces an egress data record 22 to record relevant information about the document delivered to subscriber 8 , and content router 2 produces an egress data record 20 to record relevant information about the document delivered to subscriber 17 . Correlation data is provided in the ingress data records 19 and egress data records 20 , 21 and 22 such that it can be determined which subscribers, if any, received a given published document. In addition, the publisher can optionally provide its own opaque data along with the document, which is logged in both the ingress record 19 and egress data records 20 , 21 and 22 for the document.
[0039] FIG. 2 shows a content router 30 . The content router consists of one (or more) processors (central processing unit—CPU) 31 ; a memory 32 (to hold programs and data, as well as to buffer documents being processed); input/output (I/O) ports 33 through which the content router can communicate with publishers, subscribers, other content routers, and management systems; a real-time clock 35 which holds the date and time, preferentially with a millisecond or better accuracy and resolution; and a plurality of disk drives 34 which are used to hold the data log records being produced, as well as configuration information used to control operation of the data logging operation. Note that the disks 34 are preferentially configured in a redundant configuration (RAID), as is known in the art. The I/O ports can utilize various technologies, such as Gigabit Ethernet, 10 Gigabit Ethernet, SONET, etc.
[0040] FIG. 3 shows an example processing flow 40 carried out by a content router for a document 41 sent to the content routed network from a publisher (for example, in FIG. 1 , when publisher 6 publishes a document over link 10 to content router 2 ). In step 42 , a record is created in memory to contain information which will be required for the log to be created. This includes information such as: the identification of the publisher of the published document 41 ; the date and time of document 41 arrival (determined from clock 35 , accurate to a fraction of a second, such as millisecond resolution or even finer resolution); the size of the document 41 in bytes; the priority of the document 41 (for a description of document priority and document quality of service, refer to co-filed patent application Ser. No. 11/182,756, the contents of which are incorporated herein by reference); a unique identifier for the document 41 ; etc.
[0041] At step 43 , a check is made to see if the publisher is entitled to publish documents into the network; if not an ingress record is produced at step 44 to indicate that the document 41 was not processed any further due to a lack of publisher entitlement.
[0042] At step 45 , a check is made to see if the published document 41 was successfully parsed. For example, for Extensible Markup Language (XML) published documents, a check is made to ensure that the XML document is well-formed, and optionally whether it conforms to an expected Document Type Definition (DTD) or XML schema. For a description of XML, refer to “Extensible Markup Language (XML) 1.1”, W3 C Recommendation 15 Apr. 2004, W3C, the contents of which are herein incorporated by reference. If the parsing checks do not pass, an ingress record is produced at step 46 to indicate that the published document 41 was not processed any further due to a parsing error.
[0043] At step 47 , a check is made to see if the published document 41 matches any discard filter rules. These rules are applied against each published document to see if the published document should be discarded. Such rules can be used as firewall checks, for example, to block published content that contains malicious or banned content. The rules can be applied on a per-publisher basis and/or against all publishers. For published documents which are XML, a preferred language to express the filtering rules is XPath Expressions (XPE), which can be used to match the structure and content of XML documents. For a description of XPath, refer to “XML Path Language (XPath) Version 1.0”, W3C Recommendation 16 Nov. 1999, World Wide Web Consortium (W3C), the contents of which are herein incorporated by reference. Should the published document be blocked by a filter rule, an ingress record is produced at step 48 to indicate that the published document 41 was not processed any further due to a matching discard filter. Note that the ingress record can also optionally contain details on which discard filter rule(s) caused the published document to be discarded, such as by providing the discard filter XPE or XPEs that were matched.
[0044] At step 49 , a check is made to see if the published document 41 matches any subscriptions in the network (local to the content router, or on a remote content router). The subscription matching table is populated by having the content router receive subscription registrations from local subscribers, and through the use of a content routing protocol to discover the subscriptions from other content routers in the network. Refer to Ser. No. 11/012,113 for more details. For XML documents, XPath expressions are the preferred manner for expressing subscriptions. If no subscriptions match, then an ingress record is produced at step 50 to indicate that the published document 41 was not processed any further since it did not match any subscriptions in the network.
[0045] At step 51 , the published document is forwarded to any remote destinations (i.e. other contents routers) which require a copy of the document to satisfy their local subscriptions. Note that there may be zero or more of such destinations. A copy 52 of the published document is sent over one or more links to reach the required content routers in the network. Reference is made to Ser. No. 11/012,113 for the manner in which this is done. It should be noted that only a single copy of the document is sent over a link between content routers, and that copy may be used by one or more content routers as described above. Additionally, step 53 is reached if the subscriptions of one or more local subscribers to the content router were matched. There may be zero or more such local subscribers whose subscriptions were matched. At step 53 , a check is made for each matched local subscriber to see if any subscriber filter rules have been matched. Each subscriber may optionally have one or more filter rules which, if matched against a published document, indicate that the subscriber is not to receive that published document, even if one or more subscriptions for that subscriber also match the published document. For XML documents, XPath expressions are preferentially used to express subscriber filters. If a subscriber with a matching subscription is also found to have a filter match, an egress record is produced at step 54 for that subscriber to indicate that that subscriber is not receiving a published document due to a subscriber filter match. Note that this egress record can also optionally contain details on which subscriber filter rule(s) caused the published document to be not delivered to that subscriber, such as by providing the subscriber filter XPE or XPEs that were matched. Note that for egress records, each subscriber is treated independently. If one subscriber is not delivered a document due to a subscriber filter match, other subscribers with matching subscriptions can still be delivered the document.
[0046] At step 55 , a check is made, independently for each subscriber, whether the subscriber is entitled to receive the published document 41 , based on the entitlements of the publisher and the entitlements of the subscriber; if not an egress record is produced at step 56 to indicate that the document 41 was not delivered to the subscriber due to an entitlement mismatch. Entitlements allow a content routed network to provide control over which subscribers can receive published documents from which publishers, and to provide virtual private content routed networks over a shared content routing infrastructure. Reference is made to co-filed patent application Ser. No. 11/012,168, the contents of which are incorporated herein by reference, for more information on entitlements.
[0047] At step 57 , a check is made to see if the subscriber is currently available. Note that a subscriber may be unavailable due to situations such as the subscriber system being offline. If the subscriber is not currently available, an egress record is produced at step 58 to indicate that the document 41 was not currently delivered to the subscriber due to connection setup error to the subscriber. This record is produced so that a record is available that the document would have been delivered to the subscriber if the subscriber had been available. Note that the document can be queued and delivered to the subscriber when it is later available.
[0048] When a copy 60 of a published document is delivered to a subscriber, an egress record 59 is produced. This includes the timestamp (including date and time, with a resolution of 1 millisecond or better) of when the delivery occurred. Thus, the time of delivery of each document to each subscriber is recorded. Note that if a subscriber was not available and an egress record was produced at step 58 , a separate egress record is produced at step 59 , with a separate timestamp, when the document is subsequently delivered. Thus, the time when the delivery could have first been done had the subscriber been available, and the time of eventual delivery, is separately recorded in two separate egress records.
[0049] When a content router receives a published document 61 from another content-router (for example, content router 3 receives a document from content router 2 over link 11 ), the document is processed as follows. At step 62 , a check is made to see if the document was parsed successfully. If not, step 63 is reached and processing of the 10 document stops. Note that at step 63 no record is produced since any document parsing problem should have been detected in step 45 at the content router which first received the published document from the publisher. The data logs are associated either with a publisher or a subscriber, and this situation reflects a corruption of a document between content routers. Another form of a log, such as an event log, should be issued by the content router in this situation to debug this problem. Note that a data log could instead be produced at step 63 .
[0050] At step 64 , a check is made to see if the received document 61 matches any local subscriptions. In the preferred content routing method described in Ser. No. 11/012,113, when a content router receives a document from another content router, only a comparison against local subscriptions must-be performed. Note that as described in Ser. No. 11/012,113, when a document is received over an inter-area link, further subscription matching processing must be performed relating to matching both local subscriptions and network subscriptions other than those from the area from which the document came, but this is not shown. At step 64 , if there is no match against subscriptions, then step 65 is reached and processing of the document stops without producing a data log. Note that this situation can occur when one or more subscriptions are removed from a content router as documents are in progress in the network, such that when a document reaches a content router it no longer has a matching subscription. Also, if non-perfect covering sets are utilized, as described in Ser. No. 11/012,113, a content router may receive a document for which it has no matching subscriptions. Note that FIG. 3 only shows the processing of the document for the purpose of data logging. The document may also be routed onwards to other content routers as explained above and in Ser. No. 11/012,113; this logic is omitted in FIG. 3 for clarity.
[0051] At step 66 , a check is made for subscriber filter matches. This logic has already been described above for step 53 . If a document is not delivered to a given subscriber due to a subscriber filter, then an egress record is produced at step 67 , with the same logic as described above for step 54 . Note that each subscriber with matching subscriptions is treated independently. Control then reaches step 55 , as described above.
[0052] When ingress and egress records are produced, they are written to the current traffic logging file 68 (stored on disk(s) 34 of FIG. 2 ). The current traffic logging file 68 is closed when its size reaches a configurable threshold, or when a configurable amount of time elapses (shown in step 69 ) or for some other reason such as the number of records in the file has exceeded a configurable threshold. This allows this set of records to be available for transfer off of the content router to an external system for processing. The size limit and/or record limit is made configurable since if a large amount of records are being produced, this keeps each record file to a manageable size. The time limit controls when this set of records is made available to external systems. For example, the file size could be limited to 2 Gigabytes, and the time limit can be set to one hour. Note that in FIG. 3 , records are added to the current traffic log 68 at each point that an ingress or egress record is produced, such as at steps 44 , 46 , 48 , 50 , 54 , 56 , 58 , 59 , and 67 . Note also that current records are regularly flushed to disk (vs. being held in memory) to ensure that records are not lost if the content router should crash or lose power. The preferred format for the content of data logging files is XML. Note that other formats could instead be utilized, such as fixed binary records, comma-separated values, etc.
[0053] The disk 34 contains a plurality of archived traffic log files 70 , which are available for use by external administrators of the content router, or external systems (such as a data analysis system or a billing system). The administrator or external system ( 73 and 74 ) can carry out actions on the archived traffic log files, such as retrieving the log file (via a method such as Secure File Transfer Protocol (SFTP)), and can carry out other actions such as displaying the contents of a log file, deleting log files, etc. The content router can optionally be configured to send available log files to an external SFTP server automatically (to a specified IP address, port number and logging in with a specified user name and password). Additionally, when the content router is automatically-transferring the traffic log files to an external server, the files can optionally be automatically removed from the content router once successfully transferred. The content router also monitors the amount of disk space available, and can remove old files if necessary to make room for new log files when disk space is running below a configurable threshold. In addition, at step 71 , the content router can automatically delete (step 72 ) archived log files older than a configurable threshold, such as 30 days.
[0054] The log files 70 may be optionally stored in a compressed format on disk 34 in order to save space on the disk. In addition, this saves bandwidth when the archived log files 70 are transferred to an external system. A compressed scheme such as “gzip” or other methods known in the art can be used for the compression (and later decompression) of the log files 70 .
[0055] The parameters of the data logging system, such as the configurable parameters described above, can-be set by the administrator 73 of the content router through a management interface, such as a Command Line Interface-(CLI), or via another management interface such as Simple Network Management Protocol (SNMP), as is known in the art. Status of the data logging system can also be queried, as well as actions such as listing the available archived traffic files, showing their dates and times, deleting archived files, etc.
[0056] Referring to FIG. 12 , when content routing occurs between different networks 250 and 251 belonging to different administrative domains, it is also beneficial to carry out data logging at the network boundary point (i.e. at content routers 252 and 253 for traffic crossing the link 254 which connects the two networks 250 and 251 ). For example, when a document is leaving a network 250 controlled by one administrative domain and entering network 251 controlled by a different administrative domain, an egress record 255 can be produced by content router 252 in a manner similar to the egress record which is produced for delivery to a subscriber. The egress record 255 produced can indicate the identity of the content-routed network 251 to which the document is being sent into, as opposed to the identity of a subscriber. Similarly, on ingress to a content-routed network 251 from another content-routed network 250 , an ingress record 256 can be produced by content router 253 in a manner similar to the ingress record that is produced when a document is received from a publisher. The ingress record 256 produced can indicate the identity of the content-routed network 250 from which the document is being received from, as opposed to the identity of a publisher. This can allow the tracking of traffic between content-routed networks 250 and 251 under different administrative control, and can be used to allow the network operators to bill each other, debug network problems, etc. Note that such records could also optionally be produced at the interfaces between content routers within the same content routed network for debugging purposes. For example, consider a document being sent from content router 257 to content router 258 over link 259 on its way towards other points in the same network 250 or different network 251 . Content router 257 can produce an egress record 260 indicating the identity of the content router 258 to which the document is being sent to. Note that if a document is forwarded to multiple content routers, then multiple egress records would be produced. Content router 258 can produce an ingress record 261 indicating the identity of the content router 257 from which the document is received.
[0057] FIG. 4 shows an example ingress record 80 , which is preferentially formatted using XML. The “ingRec” field 81 identifies this record as an ingress record. The “ingRec” field 81 has an attribute “num” 97 which provides a unique record sequence number, which is unique across all records produced (of any type) and across the log files produced. The record sequence number increases sequentially (i.e. the first record may be an ingress record with sequence number 1, and the next record in the same-file or in a subsequent file may be an egress record with sequence number 2). This allows an external application which is processing the logs to detect if any records have been missed or lost. For example, if an entire log file is lost, the record sequence number field 97 will allow the number of missing records to be determined. Note that all record types have the “num” field 97 . The “time” field 82 carries the timestamp 83 for the ingress record (i.e. the date/time of receipt of the document from the publisher), which is preferentially formatted as YYYY-MM-DDTHH:MM:SS.SSSZ, where: YYYY is the year, MM is the month (numeric in the range of 1 to 12), DD is the day of the month (1 to 31), HH is the hour of the day (in the range of 0 to 23), MM is the minute of the hour (0 to 59), SS.SSS is the second to 1 millisecond resolution (000.00 to 59.999), and Z indicates zulu time or universal coordinated time. The “docId” field 84 carries a unique document id 85 assigned from the content router when a document is first received from a publisher. This document id is generated in such a way as to be guaranteed unique in the content-routed network, and preferentially globally unique. For example, the document id 85 could be composed of a unique identifier for the content router, followed by a unique document serial number assigned by that content router. Or, the document id 85 can be a Universal Unique Identifier (UUID) as is known in the art. The document id 85 is a key piece of information as it is used to correlate ingress and egress data records in the content routed network. This allows the data logging system to track the disposition of each of each published document. The “size” field 86 carries the size of the document in bytes. The “pri” field 87 carries the document priority. The “user” field 88 carries the user name or other identifier of the publisher associated with the ingress record 80 , such as the example publisher user name of “SolaceSystems” 89 . The “security” field 79 carries an indication of whether a secure connection or a non-secure connection was used to receive the document from the publisher 88 . The value can be “SSL/TLS” to indicate delivery over a secure connection, or “none” to indicate the use of a non-secure connection. Field “security” 79 is optional, and if absent, a non-secure connection is indicated. The optional “userData” field 93 carries optional opaque user data provided by the publisher along with the published document. For example, the opaque user data 94 is the string “12345”. The content router does not interpret this value nor check for its uniqueness. This allows opaque data provided by the document publisher to appear in data logs associated with the document. This could be a unique identifier generated by the publisher for the document, so that there is a common name or handle for the document which can be matched in the data logs, in association with the “user” 88 (publisher)to find the disposition of the document-by the content routed network. The “actionTaken” field 90 carries an attribute “action” 91 which indicates the action taken on the document, such as the example action “discarded” 92 . In addition, the optional attribute “reason” 95 can be used to contain further details on the “action” 91 , such as a reason of “discard filter matched” 96 . This indicates that the published document was dropped by the content router due to match against a discard filter rule. Also, the optional attribute “reasonCode” 98 provides a numeric code 99 for the reason string 96 , such as a code of “5”. This allows the system processing the ingress record 80 to make determinations on a reasonCode numeric value 99 instead of a reason string value 96 . Table 1 below provides example action 91 , reason 95 and reasonCode 98 values for an ingress record 80 .
TABLE 1 Ingress Record 80 fields action 91, reason 95 and reasonCode 98 reasonCode action 91 reason 95 98 Condition “forwarded” The document was forwarded for delivery. The optional “reason” and “reasonCode” attributes are not specified under this condition. “discarded” “document “1” Document was too large for too the router to handle and large” had a correct content-length (incorrect length leads to an “xml error” reason) “no “4” The publisher did not have publisher an entitlement to publish entitlements” the document. “xml error” “3” During the parse of the document, there was an error in the XML of the document, or an internal limit was reached (such a the maximum number of attributes supported for a single XML element). “discard “5” The document matched a filter discard filter rule. matched” “no “6” The document does not match subscriptions any subscriptions in the matched” content router. “internal “7” An internal error occurred error” which prevented the router from property processing the document. “congestion” “10” The document could not be processed due to a congestion condition within the router. “zero-length “2” The document was of zero document” length.
[0058] FIG. 5 shows an example egress record 100 , which is preferentially formatted using XML. The “egRec” tag 101 identifies this record as an egress record. The “time” tag 102 carries the timestamp 114 for the egress record (i.e. the date/time of the action being carried out, such as discarding the document or delivering it to the specified subscriber), which is preferentially formatted as described above for field 83 . The “docId” field 103 carries the unique document id which was assigned to the document as described above for field 84 . The “size” field 104 , “pri” field 105 , and optional “userData” field 106 are as per described above for the ingress data record 80 . Note that the “size” field 104 reflects the document size upon delivery to the subscriber, and this may be different than the value in the ingress record for the document if the document was transformed before delivery. Similarly, the “pri” field 105 could have a different value than the ingress record 80 if the priority was modified due to rules associated with the destination subscriber. The “security” field 119 carries an indication of whether a secure connection or a non-secure connection was used to deliver the document to subscriber 107 , with the same values as described above for field 79 . The “user” field 107 contains the subscriber identity value 108 , indicating which subscriber is involved with the egress record 100 . The “actionTaken” field 109 contains an “action” attribute 110 , with a value such as “discarded” 111 , and an optional “reason” attribute 112 with an example value such as “no_entitlement” 113 , to indicate the disposition of the document with respect to the subscriber indicated by 108 .
[0059] The “actionTaken” field 109 also contains an optional attribute “ack” 118 with a value of “true” or “false”. This indicates whether the subscriber 107 acknowledged delivery of the document. This attribute would normally only be present when the action 110 has a value of “delivered”, and it is still optional since it is assumed to have a value of “true” for a delivered document if the field 118 is not present. The field “ack” 118 allows a egress record 100 to be output when a document is attempted to be delivered to a subscriber but no acknowledgement is received. The content router does not know if the subscriber successfully received the document or not (the subscriber may have received and processed the document, but crashed before an acknowledgement can be sent). If the document is subsequently re-delivered later and acknowledged by the subscriber, a new egress log for the same user 107 and docId 103 can be generated, indicating the new time 102 of delivery, and that the “actionTaken” 109 was “delivered” with “ack” 118 indicating “true”.
[0060] Note that if a document cannot be immediately delivered to a subscriber, then an egress record 100 can be generated to indicate that the document was available for delivery but not yet delivered. For example, if the connection to the subscriber is down when a document arrives, an egress-record 100 can be generated with the time 102 indicating when the document was available for delivery, and the actionTaken field 109 can indicate the reason that the document was-not yet delivered. In this way, the latency of the document through the network can be determined even though it could not be delivered to the specified subscriber 107 . If the document is queued for later delivery, then when the document is subsequently delivered, a second egress record 100 for the same user 107 and docId 103 is generated, indicating that the document was successfully delivered and acknowledged. Thus, if a document is delayed in delivery, the cause of the delay being an off-line subscriber vs. latency delays in the network can be determined through analysis of the egress records 100 .
[0061] Note that the “UserData” field 106 is optionally sent between content routers, such as when a document is sent over link 11 from content router 2 to content router 3 . Since ingress and egress records can be correlated as described above using the “DocumentId” 84 and 103 , the UserData can be associated with each egresss record 101 based on the ingress record 81 via the “DocumentId” field 84 and 103 . However, an advantage of sending the “UserData” along with the document is that it can be optionally delivered to each subscriber receiving the published document. This allows the publisher to send opaque data associated with the document to each subscriber receiving the document. A preferred method for associating meta-data with a document in a content-routed network is described Ser. No. 11/012,168. This meta-data approach is used to carry other associated data along with the document, such as document identifier, priority, etc. Table 2 below provides example action 110 and reason 112 values for an egress record 100 .
TABLE 2 Egress Record 100 fields action 110, reason 112 and reasonCode 116 reasonCode action 110 reason 112 116 Condition “delivery” The document was delivered to the subscriber. “discarded” “no “9” The subscriber does not subscriber have entitlements which entitlements” intersect with the document's entitlements. “subscriber “8” The document matches a filter subscriber filter XPath matched” expression associated with the given subscriber. “connection “11” The subscriber was not error” immediately available when a delivery attempt was made. “secure “13” The subscriber is delivery; configured for secure unsecured delivery, but the client” subscriber registered as unsecured subscriber. “unsecured “14” The subscriber is delivery; configured for unsecured secure client” delivery, but the subscriber registered as a secure subscriber. “internal “7” An internal error occurred error” which prevented the router from properly processing the document. “congestion” “10” The document could not be processed due to a congestion condition within the router.
[0062] FIG. 6 shows an example traffic logging file 120 , preferentially encoded using XML. The field “trafficLog” 121 indicates that the file contains traffic log information, and provides an optional “schemaVersion 136 indicating the version of the schema used for the file. The file starts with a “start” record 122 , then contains zero or more “ingRec” 123 and zero or more “egRec” 124 (the details of which have been explained above), with the ingress records 123 and the egress records 124 being intermingled. Note that other record types could also appear in the file interspersed with “ingRec” 123 and “egRec” 124 as explained below to log other events. At the end of the traffic log 120 is an “end” record 125 . The start record 122 and the end record 125 each contain four fields: “hostname” 126 , “ip” 127 , “radiusDomain” 128 , and “time” ( 129 in “start” record 122 ; 134 in “end” record 125 ). The “hostname” field 126 carries the host name of the content router which produced the traffic log file; an example being the hostname of “content-router-1” 130 . The “IP” field 127 carries the IP address of the content router which produced the traffic log file; an example being the IP version 4 IP address of “10.10.10.1” 131 (note that other address formats such as IP version 6 can be used). The “radiusDomain” field 128 carries the domain associated with the “user” 88 and 107 . This allows the domain name for a large number of publisher and subscriber user names to only be specified once. For example, in the user name example of “jjohnson” 108 and the “radiusDomain” 128 example of“pubsub.solacesystems.com” 132 , the full user name with the domain name applied would be jjohnsongpubsub.solacesystems.com. Note that the “user” 88 and/or 107 could carry the domain name directly, in which case the “radiusDomain” 128 would not be applied. In a “start” record 122 , the “time” field 129 carries the timestamp of the date/time where the traffic log file 120 started to hold records. The start timestamp 133 is formatted in the manner described above. In an “end” record 125 , the “time” 134 contains the timestamp of the date/time when the traffic log file 120 was completed. The timestamp value 135 is formatted as described above.
[0063] In the content routed network 1 , the various content routers, such as 2 , 3 , 4 and 5 should have their internal clocks 35 synchronized in an accurate manner, such as accurate to within a millisecond or better. One method of doing this is to use the Network Time Protocol (NTP); refer to RFC 1305, “Network Time Protocol (Version 3) Specification, Implementation and Analysis”, March 1992, The Internet Society, the contents of which are incorporated herein by reference. Accurate clock synchronization is required in order to be able to measure the latency of a published document traversing the content-routed network from a publisher to a given subscriber by subtracting the timestamp 114 in the egress record 100 from the timestamp 83 in the ingress record 80 ; where the egress and ingress record relate to the same document as determined by matching “docId” values 85 and 115 . In addition, for a given document delivered to a plurality of subscribers, the timestamp values of the various egress records 100 pertaining to the same document ID can be compared to determine the difference in delivery times among the subscribers.
[0064] An extension to the data collection method described above is to add additional data collection filters to allow the content of published documents to be reflected in the ingress records and egress records produced. This allows a further flexible means of identifying the type of content, and can be used in the billing algorithm for publishers and subscribers. This can be accomplished by allowing a configuration of one or more ingress data logging filters and egress data logging filters to be configured on each content router. Each ingress and egress data logging filter is preferentially encoded as an XPath expression when used in a network that is content routing XML documents.
[0065] FIG. 7 shows an example of an ingress data logging filter table 140 containing a plurality of ingress data logging filter rules 144 through 150 . Each rule has an associated publisher ID 141 , which may be a unique number identifying the publisher, or the publisher user name, or any other technique which can match a publisher of a document. A special value of “*” serves as a wildcard to match all publishers. The XPath expression 142 contains the rule used to match against the content of the received document. The data logging code 143 contains a string, which could be alphanumeric, which is the output associated with the rule. In the example table 140 , publisher ID “71” has three matching rules 144 , 145 and 146 ; publisher ID “ 72 ” has two matching rules 147 and 148 ; and rules 149 and 150 are active for all publishers (including publisher ID “71” and “72”). Note that more than one rule can match at the same time against the contents of a published document. For example, if a document is received from publisher ID “71” whose contents match the XPath expression “/cXML//OrderRequestHeader//Money[text( )>100]”, then the ingress data logging filter rules 140 will produce two data logging codes as output: “10” (from rule 144 ) and “20” (from rule 145 ) since both rules apply to publisher ID “71” and both match the contents of the published document.
[0066] The ingress record 80 can be augmented to carry zero or more codes, each code entry resulting from a match from table 140 as described above. In the above example, the following output would be part of the ingress record 80 . Note that zero or more codes can be associated with an ingress record.
<code>10</code> <code>20</code>
[0069] FIG. 8 shows an example egress data logging filter table 160 . In table 160 , data logging filter rules are associated with subscribers, allowing codes to be generated based on the content of the document being delivered to a subscriber. Each table entry is associated with a subscriber ID 161 , which may be a unique number reflecting a subscriber, or the username of the subscriber, or any other method of uniquely identifying subscribers. The Xpath expression 162 indicates the rule to be used to match against the document content, and the data logging code 163 indicates the value to be returned when the rule matches. The subscriber id 161 can be “*”, which indicates a wildcard that matches all subscribers. In the example table 160 , the matching rules are 164 through 170 , where rules 164 , 165 and 166 apply to subscriber ID “91”, rules 167 and 168 apply to subscriber ID “92”, and rules 169 and 170 are wildcard rules that apply to all subscriber IDs (including “91” and “92”).
[0070] As an example, when a document that matches the XPath expression “/cXML//StatusUpdateRequest” is to be delivered to a subscriber with subscriber ID “91”, rule 166 will match. As a result, the egress record 100 will also contain a “code” element as shown below. Note that zero or more code elements can be part of an egress record.
<code>statusUpdateRequest</code>
[0072] Additionally, the data associated with the matching table 160 can also be optionally sent to the subscriber as meta-data associated with the document being delivered, as per Ser. No. 11/012,168. This can provide extra information to the subscriber receiving the document, allowing the subscriber to use the associated code data to more efficiently process the received document, such as relaying the document to the correct processing subsystem or application.
[0073] Table 160 can simply be an extension of the local subscription table that is already maintained-for all local subscribers (refer to Ser. No. 11/012,113) or it can be a completely separate table. In the case where it is part of the subscription table, the Subscribe Request document described in Ser. No. 11/012,113 can be extended to carry a code 163 with each subscription. The local subscription table can then serve to both match published documents against the subscriptions of local subscribers, and to produce data logging codes 163 for placement in egress records 100 , as well as to provide the code(s) to the subscriber along with the document that matched one or more subscriptions. If different applications on the subscriber machine are using different subscriptions, the code can service to indicate which subscription has matched, and the subscriber machine can direct the document to each interested application-based on the code(s) sent by the content router along with the document.
[0074] The data logging mechanism described above can be extended to capture other events occurring in the content-routed network, especially those to which billing may be involved or to aid in the debugging of the content-routed network. For example, a new record type for subscription add or delete can be added, and this record can be generated each time a subscriber adds or deletes a subscription. An example of such a record 200 is shown in FIG. 9 . In FIG. 9 , the “subcriptionRec” field 201 indicates that this record relates to a subscription add or remove. The “time” field 202 contains the timestamp for the subscription add or delete event; the format of the timestamp has been described above. The “user” field 203 provides the username of the subscriber for which the subscription has been added or removed. The “subscription” field 204 indicates the Xpath expression of the subscription that is being added or removed, along with any associated namespace definitions. For a description of XML namespaces, refer to “Namespaces in XML 1.1”, W3C Recommendation 4 Feb. 2004, World Wide Web Consortium (W3C), the contents of which are incorporated herein by reference. In this example the “xpe” attribute 207 contains the subscription “/sol:x/foo:y”; “sol” is a namespace prefix defined in attribute 205 , where the “sol” prefix is mapped to namespace “www.sol.com”; “foo” is a namespace prefix defined in attribute 206 ; where the “foo” prefix is mapped to namespace “www.foo.com”. Note that the xpe 207 may use zero or more namespace prefixes. The optional “isFilter” element 212 indicates whether the subscription 204 is a subscription filter (value of true) or a normal subscription (value of false). If not present, a value of false (not a filter) is assumed. The “code” element 208 indicates the code that is associated with the subscription, as explained above; this field is optional. The “actionTaken” field 209 has an attribute “action” 210 which indicates the action being logged; the “action” attribute 210 can have a value of “added” or “deleted” to indicate whether the record 200 is recording a subscription add event or a subscription delete event respectively. The “result” field 211 contains the result of the operations requested by the user and can have a value of “OK” or some error code indicating the reason for the failure. Such a record allows an external billing system to use an algorithm that includes charging a subscriber for each subscription added for example. The, complexity of the xpe 207 can be factored into the charge, along with the use of a code 208 . The timestamp 202 of the add event, and a possible later delete event, allows the duration of the subscription being present to be determined.
[0075] The above data logging method provides great flexibility in logging records which can be used to debug what is occurring in a content-routed network, to bill publishers and subscribers for use of the content routed network, and to monitor service level agreement parameters such as the delivery latency across the content-routed network, and the variation in latency in the delivery of a published document to a set of subscribers which receive the document.
[0076] A publisher can be charged based on factors such as the number of documents published (determined by the number of ingress records 80 associated with a given publisher username 89 ), the volume of data published (based on the “size” field 86 ), the priority of documents carried by the network, based on the “priority” field 87 , whether or not “userData” was carried with the document, based on the presence of field 93 , and also possibly on the size of the user data 94 , based on the time of day (via timestamp 83 ), and based on whether a secure channel was used or not (via “security” field 79 ). Publishers can also be charged based on the action 92 and the associated reason 96 or reasonCode 99 . Additionally, ingress records 80 and regress records 100 can be correlated based on the unique document ID 84 and 103 as described above. This allows for the possibility of the publisher to be further charged based on factors such as the number of documents published by the publisher delivered to subscribers, the total volume of data published by the publisher delivered to subscribers, etc. Moreover, codes 143 can be used to determine the type of document published, and this can lead to different types of charges to the publisher.
[0077] Similarly, subscribers can be charged based on their usage of the content routed network, based on the number of subscriptions and their complexity, using the subscription record 200 and based on data from the egress record 100 and possibly correlated with the ingress record 80 . For example, a given subscriber (indicated by the subscriber username 108 ), can be charged based on the number of documents received (via a count of the egress records 100 for the subscriber) and/or the total volume of data received (through the sum of the size 104 of egress records 100 for the subscriber); based on the document priority (field 105 ), time of day (via timestamp 115 ), and based on whether a secure channel was used or not (via “security” field 119 ); and through correlation with ingress records based on the document ID 115 , can be further charged based on which publisher the published document came from. The subscriber can also be charged for other services, possibly on a per-use basis, such as the filtering of documents due to a subscriber filter, as indicated by action 111 and reason 113 (or reasonCode 117 ) of the egress record 100 . The subscriber can also be charged for delivery of the user data 106 , as well as for delivery of codes 163 as explained above. Moreover, codes 163 can be used to determine the type of document delivered, and this can lead to different types of charges to the subscriber.
[0078] The content router allows for data logging to be enabled or disabled on a per-publisher basis and on a per-subscriber basis. This is done via management commands, such as via a command line interface or via Simple Network Management Protocol (SNMP), or through a graphical user interface etc. Disabling of record generation for publishers or subscribers who will not be charged based on their content can reduce the total volume of data logged. Even if not used for billing purposes, logging is also useful for debugging, and thus may be enabled always, or may be enabled on demand to debug a problem with a given publisher or subscriber.
[0079] For very high volume applications, such as publish/subscribe dissemination of financial market data (e.g. stock quotes), it may be impractical to emit ingress and egress records for every stock quote published and delivered. In such cases, the logging system can be modified to emit a summary ingress record for a given publisher, for example on a 15 minute interval basis, and a summary egress record for a given subscriber, again on an interval basis such as 15 minutes. Such summary records lose details about the disposition of each individual document, but can still maintain useful information for billing purposes and other statistical purposes.
[0080] An example summary ingress record 220 is shown in FIG. 10 . The “summaryIngRec” field 221 indicates the record type as being a summary ingress record. The “time” field 222 contains the timestamp of the end of the interval duration (when the record was produced), field “intervalDuration” 223 indicates the interval duration is seconds (for example field 224 has a value of 900, which indicates 900 seconds or 15 minutes), and field “security” 235 as described above for field 79 . There can be a plurality of “actionTaken” fields, such as 228 and 229 , each of which indicates:
[0081] A unique action 230 , along with an optional reason 233 and reason code 234 as explained earlier (refer to Table 1);
[0082] A count attribute 231 which indicates the number of published documents 232 from user 227 which had the specified action 230 and reason 233 / 234 applied to them;
[0083] A size attribute 225 which indicates the total size in bytes 226 of published documents from user 227 which had the specified action 230 and reason 233 / 234 applied to them;
[0084] Using similar techniques, a summary egress billing record 270 can be utilized, as shown in FIG. 11 . The “summaryEgRec” field 271 indicates the record type as being a summary egress record. The “time” field 272 contains the timestamp of the end of the interval duration (when the record was produced), field “intervalDuration” 273 indicates the interval duration is seconds, and field “security” 285 as described above for field 119 . There can be a plurality of “actionTaken” fields, such as 278 and 279 , each of which indicates:
[0085] A unique action 280 , along with an optional reason 283 and reason code 284 as explained earlier (refer to Table 2);
[0086] A count attribute 281 which indicates the number of documents 282 for user (subscriber) 227 which had the specified action 280 and reason 283 / 284 applied to them;
[0087] A size attribute 275 which indicates the total size in bytes 276 of documents for user 227 which had the specified action 280 and reason 283 / 284 applied to them.
[0088] The summary ingress record 220 and summary egress record 270 can further be expanded by including summarized counts per data logging code 143 (ingress) and 163 (egress) which can be further used for billing or surveillance based on the type of document and/or the content of the document. Additionally, by using meta-data along with the document (as per Ser. No. 11/012,168) to allow the publisher of a given document to be known at each egress router, the summary egress record 270 can also provide summarized information per publisher, to allow the subscriber to be billed based on traffic received from various publishers (i.e. traffic from a given publisher may be charged differently from traffic received from a different publisher). Another method of doing this function is to summarize traffic based on the entitlement group of the document, so that a subscriber can be charged based on the volume of traffic delivered to the subscriber from each entitlement group.
[0089] A combination of techniques can be utilized. The choice of detailed vs. summary ingress and egress records can be configured on a per-publisher and per-subscriber basis. Or, the type of record to be generated could be based on the type of content published or delivered, using a filter to determine the record treatment. For example, for stock quotes using a outer-most XML element of “mddl”, a filter rule can be defined to indicate that published documents matching “/mddl” should use summary ingress record techniques, and otherwise a detailed ingress record should be instead produced. A similar filter can be applied before delivery to a subscriber to determine whether a summary egress record or a detailed egress record should be produced.
[0090] Another option when using summary ingress 220 and egress 270 records is to produce a detailed record (ingress 80 and egress 100 ) for a small percentage of documents, such as 1 in every 1000 documents. The selected document would still be included in the summary ingress 220 and egress 270 records. The detailed record (ingress 80 and egress 100 ) would be used to measure delivery latency from the publisher to each subscriber who received the document on a sampled basis. In order to ensure that a selected document for a detailed ingress records 80 also has an egress record 100 generated for each copy delivered to various subscribers, the ingress router would attach a meta-data item to the document to indicate that a detailed record 100 is to be produced by each egress router. This special meta-data would be removed before delivery of the document to any subscribers, as explained in Ser. No. 11/012,168.
[0091] It will be appreciated that an exemplary embodiment of the invention has been described, and persons skilled in the art will appreciated that many variants are possible within the scope of the invention.
[0092] All references mentioned above are herein incorporated by reference. | A method of managing a content routed network, involves distributing published documents through said network for delivery to subscribers; maintaining data logs pertaining to said published documents at different points in the network; and correlating the data logs to obtain information about the operation of the network. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority, under 35 U.S.C. §119, of European application No. EP 14165902.9, filed Apr. 24, 2014; the prior application is herewith incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The present disclosure relates to an improved control valve. The present disclosure focuses on a control valve wherein the flow of a fluid is a function of the position of a throttle. More particularly, the control valve as disclosed herein achieves a flow rate that is substantially independent of the pressure at the outlet of the valve.
[0003] Flow control valves are commonly employed in HVAC (heating, ventilation, air conditioning) systems of buildings. These systems typically circulate a fluid such as water through a plurality of conduits in order to provide heating or cooling. The purpose of a flow control valve is to achieve a controlled flow of a fluid through the conduits of the system.
[0004] The amount of water flowing through the valve is essentially governed by the position of the throttle. A separate flow meter measuring the flow of water through the HVAC system may thus be dispensed with.
[0005] The amount of delivered energy is then calculated as the throughput of the fluid multiplied with the temperature drop in the system. The flow of water is determined from the position of the throttle and the temperature drop is measured separately. In the context of HVAC systems, the amount of energy is frequently measured in kWh.
[0006] U.S. Pat. No. 7,128,086 B2 was granted in 2006 and discloses a flow control valve. The valve according to U.S. Pat. No. 7,128,086 B2 contains a hollow piston 110 movable along an axis X 1 . A spring 160 exerts a force on the hollow piston 110 in the direction of the same axis X 1 . A rolling diaphragm is arranged on one side of the piston 110 . The rolling diaphragm is connected to the hollow piston 110 and separates an annular channel 109 from the inside of the hollow piston 110 . The annular channel 109 is in fluid communication with the inlet 106 of the valve through a reference passageway 180 . The inside of the hollow piston 110 is in fluid communication with the outlet 108 of the valve through apertures 192 of the hollow piston 110 . The valve also contains a channel that circumferentially surrounds the hollow piston 110 and is in fluid communication with the flow channel 104 of the valve.
[0007] The pressure in the annular channel 109 of this arrangement is the pressure p 1 at the inlet 106 of the valve. Similarly, the pressure inside the hollow piston 110 equals the pressure p 3 at the outlet 108 of the valve. The pressure p 2 in the chamber surrounding the hollow piston 110 is the same as the pressure inside the flow channel of the valve 104 .
[0008] The hollow piston 110 may move under the influence of the pressures p 1 , p 2 , p 3 and under the influence of the spring 160 . As soon as the corresponding forces are balanced, the difference between the pressures p 1 at the inlet and p 2 inside the flow channel predominantly determines the flow rate through the valve. The influence of the pressure p 3 at the outlet 108 of the valve is largely eliminated.
[0009] The arrangement as disclosed by U.S. Pat. No. 7,128,606 B2 requires an element 118 for guidance of the axial movement of the piston 110 . The piston guide needs to be mounted to the valve body and a seal 130 is necessary to separate the annular channel 109 from the inside of the hollow piston 110 . The seal 130 and the rolling diaphragm separate the annular channel 109 with the highest pressure p 1 from the inside of the piston 110 with the lowest pressure p 3 . The stresses on the seal 130 and on the rolling diaphragm are particularly high along its second convolution 138 . The piston 110 is movable against the guide 118 . Due to the stresses on the seal 130 and on the rolling diaphragm, an adequate choice of materials for these highly stressed parts becomes challenging.
[0010] The gap in between the rim 117 of the guide 118 and the sleeve 114 of the piston 110 needs to be narrow in order to prevent transverse movement of the piston 110 . Yet the fluid from the inside of the hollow piston 110 must reach the space in between the rim 117 and the second convolution 138 . The second convolution 138 will otherwise not be exposed to the pressure drop between the p 1 and p 3 . Extra design measures will be required to overcome the conflicting requirement of precise guidance through the rim 117 and of full pressure drop across the second convolution 138 .
[0011] The aim of the present disclosure is at least to mitigate the aforementioned difficulties and to provide a flow control valve that meets the aforementioned requirements.
SUMMARY OF THE INVENTION
[0012] The present disclosure is based on the discovery that technical constraints on a seal adjacent to a piston can be relaxed through an adequate pressure concept. The valve disclosed herein is configured such that the pressure inside the piston is the same as the pressure of an annular channel adjacent to the piston. This measure mitigates the difficulties involved in configuring a seal in between the annular channel and the piston. Further, the pressure concept of the present disclosure avoids extra measures to ensure an even distribution of pressure around a guide element.
[0013] The above problems are resolved by a pressure independent control valve according to the main claim of this disclosure. Preferred embodiments of the present disclosure are covered by the dependent claims.
[0014] It is a related object of the present disclosure to provide a pressure independent control valve wherein friction between the movable piston and the guide element is minimized.
[0015] It is another related object of the present disclosure to provide a pressure independent control valve wherein any hysteresis affecting the movement of the piston is negligible.
[0016] It is yet another related object of the present disclosure to provide a pressure independent control valve wherein a throttle controls the fluid throughput through the valve to the point where an additional flow meter can be dispensed with.
[0017] It is another object of the present disclosure to provide a pressure independent control valve configured for measuring a temperature drop across the valve.
[0018] It is yet another object of the present disclosure to provide a heating, ventilation and air-conditioning system with a pressure independent control valve according to this disclosure.
[0019] It is another object of the present disclosure to provide a building with a heating, ventilation and air-conditioning system comprising a pressure independent control valve.
[0020] Other features which are considered as characteristic for the invention are set forth in the appended claims.
[0021] Although the invention is illustrated and described herein as embodied in a pressure independent control valve, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
[0022] The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a diagrammatic, sectional view of a pressure independent control valve according to the invention; and
[0024] FIG. 2 is a graph showing a fluid throughput versus a pressure difference.
DETAILED DESCRIPTION OF THE INVENTION
[0025] Referring now to the figures of the drawings in detail and first, particularly to FIG. 1 thereof, there is shown various principal and optional components of a pressure independent control valve as per this disclosure.
[0026] The pressure control valve contains a valve body 1 with openings forming an inlet 2 and an outlet 3 . The inlet 2 and the outlet 3 allow a flow of a fluid through the valve. In a preferred embodiment, the fluid is a liquid. In a particularly preferred embodiment, the fluid flowing through the valve is water or a mixture containing water.
[0027] A flow channel 4 is arranged along the fluid path and in between the inlet 2 and the outlet 3 . At the inlet 2 of the valve, the fluid has a pressure of substantially p 1 . The pressure of the fluid at the outlet 3 of the valve is substantially p 3 . The (overall) pressure of the fluid inside the flow channel 4 substantially is p 2 .
[0028] A throttle 5 is movably mounted inside a seat 27 in between the inlet 2 and the flow channel 4 . The position of the throttle 5 may change by moving a stem 6 back and forth along the direction indicated by arrow 7 . In a particular embodiment, the stem 6 is rotatable around the axis indicated by the arrow 7 . In an alternate embodiment, the stem 6 is not rotatable around the axis indicated by the arrow 7 .
[0029] The throttle 5 effectively varies and limits the flow of the fluid through the pressure independent control valve. To that end, the body of the throttle 5 is permeable to the fluid.
[0030] A bearing 8 restricts the movement of the stem 6 against the valve body 1 . Accordingly, the walls of the valve body surrounding the throttle 5 and the bearing 8 act as guide elements for the throttle 5 .
[0031] The bearing 8 may be of the ball-bearing type and/or of the friction-bearing type. It is envisaged that the bearing 8 also seals the pressure independent control valve, so that no fluid will leak from the valve.
[0032] A hollow piston 9 is movably mounted inside another seat in the valve body 1 . The hollow piston 9 has a cover 10 that is exposed to the pressure p 2 in the flow channel 4 . It is envisaged that the shape of the cover may be uneven or may be substantially flat. Those parts of the hollow piston 9 that are exposed to the pressure p 2 inside the flow channel 4 are impermeable to fluid. Consequently, no fluid coming from the flow channel 4 will enter the hollow piston 9 .
[0033] It is envisaged that the cross-section of the hollow piston 9 may be circular, oval, triangular, quadratic, rectangular. The cross-section of the hollow piston may actually have any shape 9 that technically makes sense.
[0034] Any movement of the hollow piston 9 is restricted by the seat in the valve body. Preferably, the seat for the hollow piston 9 effectively restricts the movement of the piston 9 to directions towards or away from the throttle 5 . The walls of the seat may hold the hollow piston 9 either through a friction-type bearing and/or through a ball-bearing. It is envisaged that the bearing will allow essentially no fluid to flow through the passage in between the hollow piston 9 and the walls of the seat in the valve body 1 . It is also envisaged that the same bearing is optimized for low friction and/or for minimum hysteresis.
[0035] The pressure independent control valve contains a further guide element 11 for the hollow piston 9 . The guide element 11 is arranged opposite to a cover 10 and penetrates a bore through the hollow piston 9 . The bore through the hollow piston 9 provides a sleeve 12 that is substantially parallel to the wall of the guide element 11 . The sleeve 12 and the guide elements 11 essentially form a bearing. This bearing may be of the ball-bearing or of the friction bearing type. The passage between the guide element 11 and the sleeve 12 needs not be fluid-tight. It is envisaged that the bearing formed by the sleeve 12 and the guide element 11 is optimized for minimum friction and/or for minimum hysteresis.
[0036] The sleeve 12 and the guide element 11 restrict the movement of the hollow piston 9 in the same manner as the aforementioned seat in the valve body 1 . It follows that technical constraints as the accuracy of guidance either through the sleeve 12 or through the seat in the valve body 1 may be relaxed to some extent.
[0037] The guide element 11 is surrounded by a biasing member 13 . In a preferred embodiment, the biasing member 13 is a spring. In a yet more preferred embodiment, the biasing member 13 is a helical spring, in particular a helical compression spring. The biasing member 13 is mounted to an end 14 of the guide element 11 . In a preferred embodiment, the guide element 11 provides a head 14 with a substantially flat surface that compresses the biasing member 13 .
[0038] An annular channel 15 , in general terms a reservoir 15 , is arranged adjacent to the hollow piston 9 . The annular channel 15 is in fluid communication with the inlet 2 of the pressure independent control valve through a passageway 16 . The annular channel 15 is also in fluid communication with the inside of the hollow piston 9 . The inside of the hollow piston 9 and the reservoir 15 in this context form a chamber. The hollow piston 9 is in general terms a displaceable element 9 or part of a displaceable element that separates the chamber from the flow channel 4 . According to a particular embodiment, the displaceable element provides no holes, orifices or apertures that allow the chamber to be in fluid communication with the flow channel 4 . In other words, the displaceable element provides a simply connected surface within the topological meaning of the term simply connected.
[0039] One or several apertures 17 are located in the wall of the hollow piston 9 that separates the annular channel 15 and the inside of the hollow piston 9 . Since the inlet 2 , the hollow piston 9 , and the annular channel 15 are all in fluid communication, these parts ( 9 , 15 , 2 , 16 , 17 ) are exposed to substantially the same pressure p 1 .
[0040] A rolling diaphragm 18 contributes to separating the pressure p 1 inside the annular channel and the pressure p 2 inside the flow channel 4 of the valve. The rolling diaphragm 18 provides a seal in addition to the aforementioned bearing formed by the hollow piston 9 and the seat in the valve body 1 . In a preferred embodiment, the presence of the two seals implies that the technical constraints for each of the two seals may be relaxed to some extent. If the sealing effect of the rolling diaphragm 18 is sufficient, the interface between the piston 9 and the valve body 1 may be permeable to some extent. Consequently, a ball bearing may be arranged in between the hollow piston 9 and the valve body 1 . The arrangement will then experience even less friction and/or less hysteresis as the hollow piston 9 moves.
[0041] The rolling diaphragm 18 may be made of any suitable flexible material. In particular embodiments, the rolling diaphragm 18 is made of rubber and/or fabric coated rubber and/or biaxially-oriented polyethylene terephthalate (MYLAR®) and/or polyester film and/or metal foil.
[0042] During operation, the pressure p 1 will exert a force to drive the hollow piston 9 towards the throttle 5 . The biasing member 13 will urge the piston 9 in the opposite direction away from the throttle 5 . A width of a gap between a rim 28 and (the cover 10 of) the piston 9 is thus allowed to vary to some extent. The amplitude of the movement of the hollow piston 9 depends on the pressure difference between the inlet 2 and the flow channel 4 .
[0043] The position of the throttle 5 relative to its seat 27 and position of the hollow piston 9 relative to the rim 28 determine the throughput of fluid through the valve. These positions are substantially independent of outlet pressure p 3 , so that the valve achieves a flow rate which is essentially independent of outlet pressure p 3 . The same is indicated on FIG. 2 , where typical fluid throughput (axis 21 ) is plotted versus pressure difference (axis 22 ). The flow of fluid is essentially constant on the right hand side of a pressure difference 23 .
[0044] Preferably, the piston 9 provides a surface 10 to separate the chamber from the flow channel 4 and the same surface is larger than the corresponding surface provided by the diaphragm 18 . In a yet more preferred embodiment, the area of the separating surface 10 of the piston 9 is at least twice the separating surface of the diaphragm 18 . In a yet more preferred embodiment, the area of the separating surface 10 of the piston 9 is at least five times larger than the area of the separating surface of the diaphragm 18 .
[0045] In a particular embodiment, the pressure independent control valve also contains an adjusting bolt 19 . The adjusting bolt 19 connects to a head 14 of the guide element 11 via a telescopic stem 20 . By turning the bolt 19 it is possible to adjust the position of the head 14 of the guide element 11 . Since the head 14 also connects to the biasing member 13 , the bolt 19 can be used to adjust the bias applied by the member 13 .
[0046] The bolt 19 is employed to alter the balance between the pressure inside the piston 9 , the pressure in the flow channel 4 and the force applied by the biasing member 13 . An adjustment of the bias applied by the member 13 has an effect on the maximum throughput of fluid through the valve. The flow of fluid through the valve will depend on the gap between the hollow piston 9 and the rim 28 . By altering the balance of pressures and forces inside the valve, this gap will also change. Consequently, an adjustment of the bias will affect the maximum flow of fluid through the pressure independent control valve. Arrow 24 on FIG. 2 indicates possible changes in the rate of fluid flow due to an adjustment of bias.
[0047] Actually, the flow of fluid through the valve is independent of outlet pressure p 3 as soon as the pressure difference between input 2 and output 3 exceeds a threshold. Any difference between p 1 and p 2 is limited to the difference between p 1 and p 3 . The pressure difference p 1 -p 2 between the inlet 2 and the flow channel 4 cannot exceed that value. If the difference between p 1 and p 2 becomes too small, the flow of fluid through the valve will depend on the pressure difference between inlet p 1 and outlet p 3 . FIG. 2 illustrates this regime as a line 25 with positive slope.
[0048] As soon as the pressure difference 22 reaches the onset 23 of constant flow, the throughput of fluid through the valve will essentially be independent of outlet pressure p 3 . By changing the position of the adjusting bolt 19 , the pressure difference required to achieve constant flow will also change.
[0049] An adjustment of the onset 23 of constant flow and of maximum throughput offers distinct benefits where pressure independent control valves need be accurate within certain limits. This is often the case in applications where a control valve renders a separate flow meter obsolete. Pressure independent control valves are then required to produce constant flow over a given range of pressure differences. Constant in this context means that the flow of fluid through the valve is determined by the position of the throttle 5 .
[0050] In yet another embodiment, a pressure independent control valve provides a plurality of temperature sensors to determine temperature drop. The temperature sensors can, for instance, be arranged at the inlet and/or at the outlet of the valve. This particular embodiment is particularly useful for metering.
[0051] By changing the position of an adjusting bolt 19 , the onset of constant flow and hence the useful range of pressure differences of a control valves is set. Likewise, the maximum throughput of fluid through a valve will affect accuracy. Also, for a given building the maximum flow of fluid will depend on the characteristics of the HVAC system employed in that building. The adjusting bolt 19 thus allows a pressure independent control valve to be adapted to the particular HVAC system of a building.
[0052] It should be understood that the foregoing relates only to certain embodiments of the invention and that numerous changes may be made therein without departing from the spirit and the scope of the invention as defined by the following claims. It should also be understood that the invention is not restricted to the illustrated embodiments and that various modifications can be made within the scope of the following claims.
[0053] The following is a summary list of reference numerals and the corresponding structure used in the above description of the invention:
REFERENCE NUMERALS
[0000]
1 valve body
2 inlet
3 outlet
4 flow channel
5 throttle
6 stem
7 arrow indicating possible movements of the stem 6
8 bearing surrounding the stem 6
9 hollow piston
10 cover
11 guide element
12 sleeve
13 bias element
14 head
15 annular channel
16 passageway
17 aperture
18 rolling diaphragm
19 adjusting bolt
20 telescopic stem
21 axis for the flow rate through the valve
22 axis for the pressure difference
23 onset of constant flow
24 variation of maximum flow
25 proportional regime of flow rate versus pressure difference
26 variation of onset of constant flow
27 seat of the throttle 5
28 rim | A pressure independent control valve contains a valve body with an inlet, an outlet and a flow channel coupling the inlet to the outlet. A hollow piston is arranged in a seat in the valve body, such that the hollow piston is configured to move. The hollow piston has an enclosure, such that the pressure independent control valve maintains different fluid pressures in the flow channel and inside the hollow piston. The pressure independent control valve contains a chamber and a biasing member to urge the hollow piston towards the chamber. The chamber is in fluid communication with the inlet and with the inside of the hollow piston, such that the valve applies substantially the same pressure inside the annular channel, at the inlet and inside the hollow piston. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This non-provisional application claims priority claim under 35 U.S.C. §119(a) on Taiwan Patent Application No. 104117170 filed on May 28, 2015, the entire contents of which are hereby incorporated by reference.
BACKGROUND
[0002] 1. Technical Field
[0003] This disclosure relates to a switch device and the controlling method of the switch device, in particular, to an electrical dual control switch device and the controlling method thereof.
[0004] 2. Related Art
[0005] Switch is an electrical element for opening the circuit, stopping the current or redirecting the current to other circuit. Therefore, switch is one of the commonly used electrical devices nowadays. While the switch is set on the ON status, the current could pass through and while the switch is set on the OFF status, the circuit will be set as an open circuit that block the current.
[0006] At first, most of the switches applied in the electrical device are one way switch (single control switch). The structure of the one way switch is relatively simple, and the characteristic of one way switch is that one switch could only control one or one set of electrical device thus make one way switch is could be control and design in a straightforward manner. With the advantage of simply use and easy to set up, one way switch is widely used in housewares, companies and for particular electric need.
[0007] FIG. 1 is a perspective view of the conventional dual switch device. The conventional dual switch device 10 includes a first switch 11 , a second switch 13 , an AC power device 15 and a loading device 17 . The first switch 11 has a first switcher 111 , a first junction 113 and a second junction 115 . The second switch 13 has a second switcher 131 , a third junction 133 and a fourth junction 135 . The first junction 113 is electrically connects with the third junction 133 , and the second junction 115 is electrically connects with the fourth junction. One end of the switcher 111 is electrically connects with the AC power device 15 , and the other end of the AC power device 15 is connected to the loading device 17 . At the other end of the loading device 17 connects the second switcher 131 . The loading device 17 could be any of the below electric device, such as lamp, exhaust fan or heater.
[0008] The switcher 111 of the first switch 11 could be switched to connect with the first junction 113 or the second junction 115 . The second switcher 131 of the second switch 13 could be switched to connect with the third junction 133 or the fourth junction 135 .
[0009] While the first switcher 11 is connected with the first junction 113 , and the second switcher 131 is connected with the third junction 133 , the current could be driven through the circuit. That is, the power from the AC power device 15 could drive through the first switch 11 , the second switch 13 to the loading device 17 . The loading device 17 is then activated. When the first switcher 111 connects with the second junction 115 , the second switcher 131 connects with the fourth junction 135 ; the current could also drive through the circuit and activate the loading device 17 .
[0010] When the first switcher 111 connects with the first junction 113 , the second switcher 131 connects with the fourth junction 135 , the circuit between the first switch 11 and the second switch 13 is opened. The current will be interrupted and the loading device 17 therefore will be shut down. When the first switcher 111 connects with the first junction 113 , the second switcher 131 connects with the third junction 133 , the circuit between the first switch 11 and the second switch 13 is also regarded as open. Therefore, the loading device 17 will be shutoff. By controlling the first switch 11 and the second switch 13 , the user could control the particular loading device 17 at different position.
[0011] There are still some limitations and improvement to be made for conventional dual electrical switch device, for instance, the loading device could not be remotely control, the usage of the power could not be calculated, there is no design for protecting against overload, and the conventional dual electrical switch device might not capable to work with touch device or sets a timer for automatically shut down the power, etc.
SUMMARY
[0012] The objection of the present invention is to provide an electrical dual control switch and the method of controlling thereof. By using the conventional wire connecting method could realize the objection of controlling the loading device via electrical. The loading device could be remotely control and the usage of the power could also effectively calculate. Further the present invention could also protected against overload, work with touch device and sets a timer for automatically shut down the power.
[0013] The present invention discloses an electrical dual control switch device applying with an AC power device and a loading device. The electrical dual control switch device could turn ON and OFF the loading device. The electrical dual control switch device comprises a first electrical switch and a second electrical switch.
[0014] The first electrical switch comprises a power connecting module, a control module and a switch. The control module respectively connects the power connecting module and the switch. The power connecting module electrically connects with the AC power device, and the control module controls the OFF or ON status of the switch. The operating status of the first electrical switch is corresponding with the operating status of the switch. One end of the power connecting module is defined as a first junction and the other end of the power connecting module is defined as a second junction.
[0015] The second electrical switch comprises a power connecting module, the control module respectively connecting the power connecting module and the switch. The power connecting module electrically connects with the AC power device. The control module controls the OFF or ON status of the switch. The operating status of the second electrical switch is corresponding with the operating status of the switch. One end of the power connecting module is defined as a third junction and the other end of the power connecting module is defined as a fourth junction. The fourth junction is connected with the second junction and the third junction is connected with the first junction.
[0016] According to the one embodiment of the present invention, between the first junction of the first electrical switch and the fourth junction of the second electrical switch disposed the AC power device and the loading device.
[0017] According to the one embodiment of the present invention, wherein only one of the first electrical switch and the second electrical switch is at ON status.
[0018] According to the one embodiment of the present invention, wherein both of the first electrical switch and the second electrical switch are at OFF status
[0019] According to the one embodiment of the present invention, wherein the switch is Power BJT, Power MOS, FET amplifiers, SCR or TRIAC.
[0020] This disclosure further discloses a method of controlling the electrical switch. The method comprises the following steps. A control module of one of the electrical switches examines whether if the power state of the AC of the AC power device is in the positive period. If the AC power device is in the positive period, the control module examines whether if the AC power of the AC power device is sufficient. If the AC power is sufficient, the control module turns on one of the switches of the electrical switches. The control module of one of the electrical switches examines whether if the power state of the AC of the AC power device is in a negative period. If the AC power device is in the negative period, proceeding a 100˜2000 s delay, then the control module turning on the switch again.
[0021] According to the one embodiment of the present invention, the electrical switches comprising a first electrical switch and a second electrical switch, and the first electrical switch is set on an ON status, the method further comprising the following step. If the first electrical switch is in a positive period, calculates the integrated area of the positive period. The control module determines whether the integrated area of the positive period exceeds a threshold value. If the integrated area of the positive period exceeds the threshold value, the second electrical switch is at an OFF status. If the integrated area of the positive period does not exceed the threshold value, the second electrical switch is at an ON status.
[0022] According to the one embodiment of the present invention, the electrical switches comprise a first electrical switch and a second electrical switch. The first electrical switch is set at an OFF status. The method further comprising the following step: the control module of the first electrical switch examines whether if the power state of the AC of the first electrical switch is in a negative period. If the first electrical switch is in the negative period, calculates the integrated area of the negative period. The control module determines whether the integrated area of the negative period exceeds a threshold value. If the integrated area of the negative period exceeds the threshold value, the second electrical switch is at an OFF status.
[0023] According to the one embodiment of the present invention, the electrical switches comprise a first electrical switch and a second electrical switch. The first electrical switch is set on an OFF status. The method further comprising the following step: the control module of the first electrical switch examines whether if the power state of the AC of the first electrical switch is in the negative period. If the first electrical switch is in the negative period, calculates the integrated area of the negative period. The control module determines whether the integrated area of the negative period exceeds a threshold value. If the integrated area of the negative period exceeds the threshold value, the second electrical switch is at an OFF status.
[0024] This disclosure further discloses a method of controlling the dual electrical switch to shut off the other electric switch. The method comprising the steps of: setting the first electrical switch at an OFF status. The control module of the first electrical switch examines whether if the power state of the AC of the first electrical switch is in the negative period. If the AC power device is in the negative period, the control module of the first electrical switch transmits a shutting down instruction. Sets the second electrical switch at an OFF status. The control module of the second electrical switch examines whether if the power state of the AC of the second electrical switch is in the positive period. If the AC power device is in the positive period, a power connecting module of the second electrical switch receives the power from the AC power device. The control module of the second electrical switch examines whether there exists a shutting down instruction on the power wire. If the shutting down instruction is detected, the control module of the second electrical switch shuts down the switch of the second electrical switch.
[0025] According to the one embodiment of the present invention, further comprise the following steps. If the control module of the first electrical switch examines the power state is in the negative period. The control module of the first electrical switch sets the first electrical switch at an ON status and interrupting the power of the power wire. If the power state of the AC of the second electrical switch is in the positive period, the control module examines whether the power on the power wire is sufficient. If the power is sufficient, the power connecting module of the second electrical switch receives the power from the AC power device. If not, the control module of the second electrical switch shuts the switch off.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] This disclosure will become more fully understood from the detailed description given herein below for illustration only, and thus not limitative of this disclosure, wherein:
[0027] FIG. 1 is a perspective view of the conventional dual switch device.
[0028] FIG. 2 is a perspective view of the dual electrical switch in accordance with one embodiment of the present invention.
[0029] FIG. 3 is a perspective view of the dual electrical switch in accordance with one embodiment of the present invention.
[0030] FIG. 4 illustrates a graph of the AC wave of the AC power device.
[0031] FIG. 5 illustrates flowchart of the operation of the dual electrical switch of one of the embodiment of the present invention.
[0032] FIG. 6 illustrates a graph of waveform of the AC wave of the two electrical devices.
[0033] FIG. 7 illustrates flowchart of controlling the dual electrical switch to shut off the other electric switch of the present invention.
[0034] FIG. 8 also illustrates flowchart of controlling the dual electrical switch to shut off the other electric switch of the present invention.
[0035] FIG. 9 illustrates another flowchart of controlling the dual electrical switch to shut off the other electric switch of the present invention.
[0036] FIG. 10 illustrates flowchart of controlling the dual electrical switch to shut off the other electric switch of the present invention.
[0037] FIG. 11 illustrates flowchart of controlling the dual electrical switch to shut off the other electric switch of the present invention.
DETAILED DESCRIPTION
[0038] The term “couple” and “connect” are intended to mean either an indirect or direct electrical connection in the specification. In other words, the wording of “a first electric switch is coupled to a second electric switch.” disclosed in the specification or the claims section means that the first electric switch is directly electrically connected to the second electric switch, or the first electric switch is indirectly electrically connected to the second electric switch via some other means or devices.
[0039] The present invention will be explained with the following embodiments, for those in art will be easy to realize and exercise with these embodiments. It should be noted that, these embodiments shall not be interpreted as limitations. For the clarity purpose, same elements will share same reference numbers.
[0040] Please refer to FIGS. 2-4 , where FIG. 2 and FIG. 3 illustrate the perspective view of the dual electrical switch in accordance with embodiments of the present invention. FIG. 4 illustrates a graph of the AC wave of the AC power device.
[0041] The electrical dual control switch device 20 applying with an AC power device 25 and a loading device 27 . The electrical dual control switch device 20 comprises a first electrical switch 21 and a second electrical switch 23 . The first electrical switch 21 comprises a power connecting module 215 , a control module 217 and a switch 219 . The second electrical switch 23 comprises a power connecting module 235 , the control module 237 and the switch 239 . One end of the power connecting module 215 is defined as a first junction 211 and the other end of the power connecting module 215 is defined as a second junction 213 . Similarly, One end of the power connecting module 235 is defined as a third junction 231 and the other end of the power connecting module 235 is defined as a fourth junction 233 . The fourth junction 233 is connected with the second junction 213 and the third junction 231 is connected with the first junction 211 . The AC power device 25 is disposed between the first junction 211 and the loading device 17 . The loading device 17 will be disposed between the AC power device 25 and the fourth junction 233 . In addition, the loading device 17 could be any of the below electric device but not limit to, such as lamp, exhaust fan or heater.
[0042] The first electrical switch 21 and the second electrical switch 23 respectively detect the AC waveform of the power wire to understand the operating status of the particular switch. The operating status hereinafter is referring to the ON and OFF status. The steps will be discussed in details at FIG. 7 to FIG. 9 . When the loading device 27 turns on, only one of the first electrical switch 21 and the second electrical switch 23 will be turn on, and the other will be turn off. For example, in one embodiment the first electrical switch 21 will be turned on and the second electrical switch 23 will be turn off, vice versa, The controlling mechanic will be described in at the following passage along with FIG. 10 and FIG. 11 .
[0043] When the first electrical switch 21 turns on and the second electrical switch 23 turns off, the power provided by the AC power device 25 will go through the first electrical switch 21 and transmit to the loading device 27 , then drive the loading device 27 . In different condition, while the second electrical switch 23 is turn on (the first electrical switch 21 is off), the power provided by the AC power device 25 thus will go through the second electrical switch 27 . Since the first and second electrical switches are electrical switches, these switches could be easily control via circuit design and internet to realize the objection of remote control the loading device. Furthermore, it also makes it more easily to calculate and collects the power usage of the loading device. Thus could monitor the overall power to protecting against overload. Also, it could also capable to work with touch device or sets a timer for automatically shut down the power.
[0044] According to the one embodiment of the present invention, wherein the switches in the present invention could be Power BJT, Power MOS, FET amplifiers, SCR or TRIAC.
[0045] Please refer to FIG. 3 and FIG. 4 , the first electrical switch 21 of the present invention comprises a power connecting module 215 , a control module 217 and a switch 219 . One end of the power connecting module 215 is defined as a first junction 211 and the other end of the power connecting module 215 is connected with the switch 219 . The other end of the switch 219 is defines as a second junction 213 . The control module 217 respectively connects with the power connecting module 21 and the switch 219 .
[0046] FIG. 4 illustrates a graph of the AC wave of the AC power device. AC power 40 includes two portions: positive period power 41 and negative period power 43 . When the first electrical switch 21 turns on, the control module 217 will examine whether the AC power is sufficient. If the power is sufficient, the power connecting module 215 will gather some of the power from the positive period power 41 (as shown in FIG. 4 ). Then, the control module 217 turns on the switch 219 and transmits the power 411 to the loading device 27 .
[0047] The detail operation of the electrical switch will be shown in FIG. 5 . The operation of the second electrical switch will be similar to the first electrical switch, thus will not be description again.
[0048] Please refer to FIG. 5 , which illustrates flowchart of the operation of the dual electrical switch of one of the embodiment of the present invention. At step S 501 , the control module 217 of the first electrical switch 21 examines whether if the power state of the AC of the AC power device 25 is in the positive period. If the AC power device 25 is in the positive period, then proceed to step S 503 . If not, then proceed back to step S 501 to re-examine the power state of the AC power device 25 . At step S 503 , the control module 217 continues examining whether if the AC power of the AC power device 25 is sufficient. If the AC power is sufficient, then proceed to step S 505 , if not then proceed back to step S 503 . At step S 505 , the control module 217 turns on the switch 219 and transmits the power to the loading de vice 27 . Then, in step 507 , the control module 217 of the first electrical switch 21 examines whether if the power state of the AC of the AC power device 25 is in a negative period. If the AC power device 25 is in the negative period, then proceeds to step S 509 , if no then proceed back to S 507 . At step S 509 , proceeds a 100˜2000 μs delay, then proceed to step S 511 . At step S 511 , the control module 217 turns the switch 219 on again.
[0049] Please refer to FIG. 6 to FIG. 9 , these figures illustrate a graph of waveform of the AC wave of the two electrical devices. FIG. 6 illustrates a graph of waveform of the AC wave of the two electrical devices. The AC waveform 61 illustrates the waveform 61 of the electrical switch at the ON status, and the waveform 63 depicts the other electrical switch at the OFF status.
[0050] FIG. 7 illustrates flowchart of controlling the dual electrical switch to shut off the other electric switch of the present invention. Furthermore, FIG. 7 shows how one of the switches in dual electrical switch detects the other electrical switch, and while detecting the switch is set at an OFF status. First, step S 701 , the control module 217 of the electrical switch 21 detects whether the AC power of the electrical switch 21 is in a positive period. If it is in a positive period, then proceed to step S 703 . If not, then proceed back to step S 701 keep detecting. At step S 703 , the control module 217 calculates the integrated area of the positive period. Then proceed to step S 705 , does the integrated area of the positive period exceeds a threshold value? If the integrated area of the positive period exceeds the threshold value, indicates that the other electrical switch 23 is at an OFF status (step S 707 ). If the integrated area of the positive period does not exceed the threshold value, then indicates that the other electrical switch 23 is at an ON status (step S 709 ).
[0051] FIG. 8 also illustrates flowchart of controlling the dual electrical switch to shut off the other electric switch of the present invention. Furthermore, FIG. 8 also shows how one of the switches in dual electrical switch detects the other electrical switch, and while detecting the switch is set at an OFF status. First, step S 801 , the control module 217 of the electrical switch 21 detects whether the AC power of the electrical switch 21 is in a negative period. If it is in a negative period, then proceed to step S 803 . If not, then proceed back to step S 801 . At step S 803 , the control module 217 calculates the integrated area of the negative period. Then proceed to step S 805 , does the integrated area of the negative period exceeds a threshold value? If the integrated area of the negative period exceeds the threshold value, indicates that the other electrical switch 23 is at an OFF status (step S 807 ). If the integrated area of the negative period does not exceed the threshold value, then indicates that the other electrical switch 23 is at an ON status (step S 809 ).
[0052] The first electrical switch is set at an OFF status. The method further comprising the following step: the control module of the first electrical switch examines whether if the power state of the AC of the first electrical switch is in a negative period. If the first electrical switch is in the negative period, calculates the integrated area of the negative period. The control module determines whether the integrated area of the negative period exceeds a threshold value. If the integrated area of the negative period exceeds the threshold value, the second electrical switch is at an OFF status.
[0053] FIG. 9 illustrates another flowchart of controlling the dual electrical switch to shut off the other electric switch of the present invention. The present method combines the methods that shown in previous FIG. 7 & FIG. 8 , wherein in this method while detecting the status of other electrical switch (such as electrical switch 23 ), the detecting electrical switch (such as electrical switch 21 ) will be set at the OFF status. First of all, in step S 901 , the control module 217 of the electrical switch 21 detects whether the electrical switch 21 itself is in a positive period. If the electrical switch 21 itself is in a positive period, then proceeds to step S 903 . If not, then process back to step S 901 . At step S 903 , the control module 217 calculates the integrated area of the positive period. Then, proceed to step S 905 , the control module 217 determines whether the integrated area of the positive period exceeds a threshold value. If the integrated area of the positive period exceeds the threshold value, states that the other electrical switch 23 is at an OFF status (step S 907 ). If the integrated area of the positive period does not exceed the threshold value, then proceed to step S 909 . At step S 909 , the control module 217 of the electrical switch 21 detects whether the AC power is in a negative period. If the AC power is in a negative period, then proceed to step S 911 . If not, then proceed back to step S 909 keep detecting. At step S 911 , the control module 217 calculates the integrated area of the negative period. Then proceed to step S 913 , the control module 217 determines whether the integrated area of the negative period exceeds a threshold value. If the negative period exceeds a threshold value, then states that the other electrical switch 23 is set at an ON status (step 917 ).
[0054] The first electrical switch is set on an OFF status. The method further comprising the following step: the control module of the first electrical switch examines whether if the power state of the AC of the first electrical switch is in the negative period. If the first electrical switch is in the negative period, calculates the integrated area of the negative period. The control module determines whether the integrated area of the negative period exceeds a threshold value. If the integrated area of the negative period exceeds the threshold value, the second electrical switch is at an OFF status.
[0055] FIG. 10 illustrates flowchart of controlling the dual electrical switch to shut off the other electric switch of the present invention. In the present invention, it could be control via the conventional power transmitting wire, and the switch that turns on will be set at the starting point of the positive period of negative period.
[0056] As shown in the figure, the electrical switch is setting at on. At step S 1101 , the control module examines whether if the power state of the AC is in the positive period. If the AC is in the positive period, then go to step S 1003 . At step S 1003 , the power connecting module will receive the power from the AC power device. If the AC is not in the positive period, then go back to step S 1005 . At step S 1005 , the control module of examines whether there exists a shutting down instruction on the power wire. If the shutting down instruction is detected, the control module shuts down the switch (step S 1007 ). If there is no the shutting down instruction, then the control module turns on the switch (step S 1009 ).
[0057] Meanwhile, the electric switch at OFF status could proceed to step S 1002 , which the control module will examine whether if the power state of the AC is in the negative period. If the AC power device is in the negative period, then proceed to step S 1004 . At step S 1004 , the control module transmits a shutting down instruction to the power wire. If the AC power device is not in the negative period, then proceed back to step S 1002 . Then, proceed to step S 1006 , the control module examines whether if the other switch in at the OFF status. If the other switch is OFF, then finish the process. If the other switch is ON, then proceed to step S 1002 .
[0058] As shown in FIG. 11 , FIG. 11 illustrates flowchart of controlling the dual electrical switch to shut off the other electric switch of the present invention. The method is practice through conventional power wire, the electrical switch that turns on must be at the start of the positive period or negative period.
[0059] In FIG. 11 , the electrical switch at ON status and continue to proceed to step S 1101 . The control module examines whether the power state is in the negative period. If the power state is in the negative period then proceed to step S 1103 , if not proceed to back to step S 1101 . At step S 1101 the control module detects whether there is any power on the power wire, if there is power exist then continue to step S 1105 , if not then go back to step S 1107 , the electrical switch will be set to OFF. At the step S 1105 , the power connecting module receives the power from the AC power device. Then, in step S 1109 , the electrical switch is set on the ON status.
[0060] At the meanwhile, the electrical switch set on the OFF status and proceeding to the step S 1102 . The control module examines whether the power state is in the negative period. If the the power state is in the negative period then proceed to step S 1104 , if not proceed back to step S 1102 .
[0061] At the step S 1104 , the other electric switch is shut off and then proceeds to step S 1106 . At step S 1106 , the control module examines whether the other electric switch is shut off If the other electric switch is turn off, then finish the process. If not, proceed back to step S 1102 .
[0062] The foregoing description of the exemplary embodiments of the disclosure has been presented only for the purposes of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations are possible in light of everything above. The embodiments were chosen and described in order to explain the principles of the disclosure and their practical application so as to enable others of ordinary skill in the art to utilize the disclosure and various embodiments and with various modifications as are suited to the particular use contemplated. Alternative embodiments will become apparent to those of ordinary skills in the art to which the present disclosure pertains without departing from its spirit and scope.
[0063] Accordingly, the scope of the present disclosure is defined by the appended claims rather than the foregoing description and the exemplary embodiments described therein. | The present invention disclosed an electrical dual control switch device and the method of controlling thereof. By applying two electrical switches with connection method of conventional mechanical type dual control switch device. The operating status of the electrical switch could be detected by the AC waveform of the power transmission line of the other electrical switch. Therefore, the objection of electrical controlling the loading device will be realized. The loading device could be remotely control and the usage of the power could also effectively calculate. Further the present invention could also protected against overload, work with touch device and sets a timer for automatically shut down the power. | 7 |
RIGHTS OF THE GOVERNMENT
The invention described herein may be manufactured and used by or for the Government of the United States for all governmental purposes without the payment of any royalty.
FIELD OF THE INVENTION
The present invention relates to sintering ceramics, and more particularly to laser sintering of ceramic fibers.
BACKGROUND OF THE INVENTION
Lasing media in fiber format enjoys an advantage of high surface-to-volume ratio, resulting in efficient cooling, and consequent preference over other geometries for high power applications. Thus, fiber lasers rank prominently among the highest power lasers in existence today, with some producing beams of over ten kilowatts in power. Further, a fiber wave-guiding configuration can be structured to allow only a single mode of light output from the laser, resulting in superior beam quality relative to other geometries. Additional advantages of fiber waveguide laser geometry, insofar as the use of free-space optics is reduced or even eliminated, can include resistance to misalignment due to vibration or temperature fluctuations, ease of alignment, and compactness.
Having arrived at such high powers from the contemporary fiber laser material, i.e., silica, the ability to produce even higher powers has begun to become limited by the fundamental material properties of that lasing media. Thus, other materials possessing qualities superior to those of silica for purposes of fashioning fiber lasers are needed. Ceramic materials are strong candidates for this purpose. Several compounds are prominent among this class of materials as having unique potential to serve as useful high-power laser materials, for example, lutetium oxide (or Lutetia), yttria, and yttrium aluminum garnet (Y 3 Al 5 O 12 or YAG). These materials are expected to be preferable to silica as fiber lasing media for two reasons related to their inherent material properties. First, the thermal conductivities of these materials are higher than those of silica. A higher thermal conductivity allows for waste heat to be extracted from the active lasing media more efficiently. Second, these materials typically permit higher levels of dopant to be introduced into their matrices than does silica. Higher dopant levels may result in achieving the same degree of absorption as in silica, while using shorter lengths of fiber relative to silica. This may be useful due to the fact that Stimulated Brilloiun Scattering, or SBS, a phenomenon which is deletrious to efficient high-power laser operation, is more prone to occur in longer lengths of fiber. SBS is a major concern to producers of higher power fiber lasers.
Presently, optical-quality YAG fiber has been created in single crystal form, only. However, ceramic fibers of these materials may be more desirable. The single crystal forms of these materials are more limited in their ability to incorporate high concentrations of certain dopants such as Neodymium, than the polycrystalline ceramic forms. Additionally, the methods by which single crystal fibers are produced—such as Laser Heated Pedestal Growth (LHPG), and Edge-Defined Film-Fed Growth (EDF, or EDFG)—generally cannot produce a fiber of diameter much less than 100 microns. This is due primarily to the fact that growth of single-crystals passes through a liquid phase, and when liquid phases of these materials are created with such small dimensions, capillary instabilities cause the liquid neck to collapse into a drop. However, in order to create fibers capable of delivering single mode beams, fibers with diameters on the order of 20 microns or less are desirable. Extrusion, may be one practical method to create ceramic fibers of such small diameters.
In any optical material, optical loss due to scatter must be minimized. In a ceramic optical material, scatter typically originates at the grain boundaries. Optical scattering at grain boundaries of a ceramic depends on three things: index isotropy, homogeneity or absence of additional phases, and porosity. If the optical indicatrix is nonspherical, scatter will generally occur at grain boundaries as the light moves from one domain to another and experiences a change in the index of refraction. Therefore, hexagonally-close-packed materials, such as Sapphire, are typically unattractive as optical ceramics. However, for materials of cubic symmetry, such as those mentioned earlier, the light sees the same index of refraction as it moves from one domain to another, and so no refractive scatter is produced. Any optical inhomogeneity present at the grain boundary, such as a pore, or a different phase, will cause scatter.
Using appropriate preparation for both oxide and non-oxide bulk polycrystalline laser materials, a ceramic optic can be made of sufficiently low scatter as to be useful as a laser optical component. Commercially available examples include ZnSe and YAG. While the size of the grains themselves are irrelevant to scatter, they may have implications for the physical strength of the material, with smaller grains typically resulting in ceramic parts of greater strength and larger grains producing weaker strengths. For purposes of fabricating a fiber, smaller grains may also result in a smoother surface on the fiber than larger grains. Insofar as light can scatter from index inhomogeneities on the waveguide surface, large grain sizes in ceramic waveguides will be likely to “indirectly” result in increased scatter, in the absence of a polishing technique for smoothing the waveguide surface.
However, preparation of a pore-free ceramic is not trivial. Due to the thermodynamics of atomic mass-transport, the grains of a ceramic will change in size and shape when the material is heated. Depending on the initial porosity of the ceramic, and in consideration of various other factors such as the surface tension of the material's liquid phases, the possible presence of eutectics, the ambient pressure, and the heating rate, a given heating regimen may cause pores to either grow and increase in size, or to shrink and perhaps even to disappear entirely. Which direction the material takes depends on the details of that material's thermodynamics, in relation to the particulars of the heating regimen employed. The technical term used to describe such a pore-closing heating regimen is “sintering”. During sintering, the pores are more likely to disappear if the initial pre-sintering porosity of the ceramic is lower. Pores are generally less likely to disappear if the pre-sinter porosity is high. The initial grain size may also be a factor in pore elimination, with smaller grains being more likely to result in pore elimination than larger grains for identical initial porosities.
Creating a ceramic part of low initial, pre-sinter porosity involves considerable optimization of material chemistry and initial grain size. The net result of those preparations is an object termed a green body, which is a ceramic part in the approximate shape of the desired final geometry. This green body may have appropriately low initial porosity, and may also contain the presence of binders, or chemical materials needed solely for the purpose of holding the initial grains together, in their “green”, pre-sintered, state.
Generally, heating for the sintering process is accomplished using a furnace. One of the factors which promotes the elimination of pores during a sinter is pressure of a gas or air around the part. In some cases, it has been found that sintering a part, while the part is “immersed” in a high-pressure gas, is beneficial for elimination of the pores. An explanation for this phenomenon is not so much that the pressure simply presses the grains closer together. Rather, the pressure provides a thermodynamic potential which motivates pore elimination. In order to harness this reality for the purpose of effective sintering, a Hot Isostatic Press, or HIP furnace may be utilized. A HIP is a furnace equipped with a high-pressure enclosure.
In other cases it has been found that sintering the ceramic in a vacuum may also be beneficial for pore elimination. An explanation for pore elimination in a vacuum is that if the ceramic part is in a vacuum, then the pores within the ceramic part should be empty of gas. If there were no vacuum, then the gasses in the pores must at some point dissolve into the solid in order for the pore to be eliminated. However, if a vacuum is present, then there is no gas or other matter that requires dissolution into the solid, so pore closure should occur more readily. In the event that vacuum sintering is found to be preferable, one would typically use a vacuum furnace.
However, high costs are associated with using such furnaces, including replacement costs of heating elements with finite life spans. Additionally, processing chambers sizes of these furnaces, which provide the high pressures or vacuums, limit the sizes of fibers that may be processed. What is needed, therefore, is a low cost system and method for generating ceramic fibers for laser or other applications without the limitations and challenges set out above and using processes that may be performed at atmospheric pressure.
SUMMARY OF THE INVENTION
Embodiments of the invention address the need in the art by providing a method of generating an optical fiber. A green fiber consisting primarily of a ceramic material is created. The green fiber is then sintered with a laser by moving the green fiber through a beam of the laser to increase the density of the fiber after sintering. The resulting density of the fiber after sintering is greater than 99 percent dense.
In some embodiments, creating the green fiber includes spinning a viscous pre-ceramic polymer/nanopowder mixture to create the green fiber. In other embodiments, creating the green fiber includes creating a slurry consisting of the ceramic material and extruding the slurry through a die to create the green fiber. The slurry in some embodiments includes a ceramic nanopower, a binder, and a liquid. The ceramic nanopowder may include YAG or both YAG and a dopant. The binder may include polyethylenimine. In some embodiments, prior to sintering the green fiber, the green fiber may be processed to remove the binder and the liquid.
As the green fiber is moved through the beam of the laser, a portion of the green fiber is held in the beam of the laser for an amount of time to sinter the portion of the green fiber before moving a next portion of the green fiber into the beam of the laser. In some embodiments, the amount of time is approximately one minute.
Embodiments of the invention also provide a system for creating a continuous optical fiber. In these embodiments, the system includes an extruder configured to extrude a ceramic slurry as a green fiber, a processing chamber configured to receive the green fiber, and a laser configured to direct a laser spot on the green fiber exiting the processing chamber to sinter the green fiber. The processing chamber is configured to process the green fiber to remove the binder and the liquid. In some embodiments, the system further includes an additional laser configured to direct a laser spot in conjunction with laser spot of the first laser on the green fiber exiting the processing chamber to sinter the green fiber.
In an alternate embodiment of the system for creating a continuous optical fiber, a first laser is configured to direct a first laser spot on the green fiber exiting the extruder and further configured to create a first temperature for calcining the green fiber. Subsequently, a second laser may be configured to direct a second laser spot on the green fiber after calcining and may further be configured to create a second temperature for sintering the green fiber. As with previous embodiments, the density of the fiber after sintering is greater than 99 percent dense. Additional laser spots from additional lasers may be used in conjunction with second laser spot of the second laser on the green fiber for sintering the green fiber.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given above, and the detailed description given below, serve to explain the invention.
FIG. 1 is a schematic diagram of an extrusion process for generating green fibers.
FIG. 2 is a diagrammatic cross section of the extruded green fiber of FIG. 1 .
FIG. 3 is a schematic diagram of a processing step for the extruded green fiber of FIG. 1 .
FIGS. 4A and 4B are reproductions of scanning electron microscope images of green fibers after sintering.
FIG. 5 is a schematic diagram of an exemplary laser configuration for sintering the green fiber in FIG. 1 .
FIG. 6 is a schematic diagram of an alternate laser configuration for sintering the green fiber in FIG. 1 .
FIG. 7 is a schematic diagram of another laser configuration for sintering the green fiber in FIG. 1 .
FIG. 8 is a schematic diagram of still another laser configuration for sintering the green fiber in FIG. 1 .
FIG. 9 is a schematic diagram of an embodiment of a system that could be used for a continuous fiber production.
FIG. 10 is a schematic diagram of an alternate embodiment of a system that could be used for a continuous fiber production.
It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the sequence of operations as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes of various illustrated components, will be determined in part by the particular intended application and use environment. Certain features of the illustrated embodiments have been enlarged or distorted relative to others to facilitate visualization and clear understanding. In particular, thin features may be thickened, for example, for clarity or illustration.
DETAILED DESCRIPTION OF THE INVENTION
Single crystal YAG has been a commercial material of choice as a laser host for neodymium (Nd) and other active ions. Ceramic (dense polycrystalline) YAG is known to have significant benefits over single crystal forms, such as, for example, a high doping concentration. Fibers are known to be ideal geometries for laser hosts, as they offer a maximal surface area to volume ratio for efficient heat extraction. A ceramic YAG in fiber geometry would combine both these advantages for fiber laser applications. Embodiments of the invention provide a system and method capable of creating a ceramic YAG body in fiber geometry.
Conventional approaches to sintering ceramics include atmospheric furnaces, Hot Isostatic Press (HIP) furnaces, and vacuum sintering. All three of these sintering options require expensive devices. Lifetimes of furnace heating elements are finite, and once worn out, they are expensive to replace. A typical furnace in a laboratory setting, used daily to 1500 C, will probably need its elements replaced every six months. HIP and Vacuum furnaces are also large, requiring room for pumps and/or gas storage and compression. Lasers are advantageous in all these respects. The footprint of a CO 2 laser, for example, can be less than one square foot in some configurations, and it's price may be less than one tenth that of a HIP. CO 2 lasers have lifetimes of tens of thousands of hours. Furthermore, while laser sintering may be performed at ambient atmospheric pressures, if it should ever be desired, lasers may also be used for sintering a part under vacuum or pressure, by feeding the beam into a pressure or vacuum vessel with an appropriate window.
Besides the advantages in space and cost, a laser offers other advantages as well. Whereas the heating rate in conventional furnaces using resistive heating elements is at most a few degrees per minute, use of a laser to heat a fiber allows heating rates of hundreds of degrees per second. Sintering under such rapid heating rates is empirically known to result in improved results in bulk samples, and has been implemented in a technique known variously as spark-plasma-sintering (SPS), current-assisted sintering, or field assisted sintering. In this bulk sintering technique the part is pressed between two graphite dies, and a large current is run through the dies. Thus, the part is heated by the die. This methodology does often produce distinctively advantageous results: very fast full, densification (for example, 10 minutes instead of 10 hours), with negligible grain growth.
Utilizing embodiments of the invention, densification of an extruded fiber green body is possible by laser action at atmospheric pressure. These embodiments provide the possibility of creating a fully dense fiber with a low cost and easily implemented method. Laser sintering also offers the possibility if minimizing contamination of the fiber, as other sintering techniques require the large surface areas of furnaces and presses to be heated and exposed to the fiber, whereas with laser processing it is only the fiber itself, which is heated. Laser sintering also lends itself easily to implementation in a vacuum environment, to achieve vacuum laser sintering. This sintering method may also be applicable to fibers of other ceramic systems as well, such as lutetia and many others.
In some embodiments, short lengths of low scatter material with cladding and doping may be produced, demonstrating efficient lasing. In this context, two specific embodiments define processes to produce fine diameter (less than 75 μm) polycrystalline ceramic fibers. In a first embodiment and referring to FIGS. 1 and 2 , high purity commercially available YAG nanopowders 10 , such as those produced by Nanocerox, Inc. of Ann Arbor, Mich., are mixed with binder 12 and liquid 14 to form a slurry 16 . The liquid 14 may include water, hydrocarbon solvents, or other liquids known in the art. Binders 12 may include polyethylenimine, such as that produced by Sigma-Aldrich, Co. of St. Louis, Mo., though other binders may also be used. A rheology of the slurry 16 may be adjusted to a high viscosity shear-thinning state. The extrusion mix showed favorable shear thinning behavior when it contained approximately 25 wt % to 35 wt % water. A resulting paste is then extruded by extruder 18 through a small diameter (30-100 μm) die 20 to produce a green fiber 22 .
Alternately, and in a second embodiment, high purity commercially available YAG nanopowder 10 may be added to a preceramic polymer consisting essentially of a high molecular weight polymer, a chelating agent, and an yttrium salt. Additionally, an alumina sol may be added to this mix to maintain approximately a 3:5 ratio of yttrium to aluminum cations. The mixture may then be heated and cooked down to a tacky high viscosity mass suitable for spinning fibers in order to generate green fibers 22 . Conversely, the green fiber 22 may also be drawn from a suitable mixture.
Traditional methods of densifying green bodies usually include applying high isostatic pressures and temperatures for periods of several hours. Prior to this sintering process, and in some embodiments, the green fiber 22 may be placed in one or more processing chambers 30 for evaporating the liquid and calcining the green fiber 22 to remove the binding agent, leaving only the YAG material and any dopants in the green fiber 32 as illustrated in FIG. 3 . Sintering assists in densifying the fiber material, essentially eliminating the gaps as can be seen in FIGS. 4A and 4B . However, due to the limited volume of traditional high pressure chambers, these methods are not well suited to densification of fiber lengths greater than a few centimeters at most.
Green fiber 32 was sintered by heating in a 10 micron CO 2 laser beam, to which YAG is entirely opaque, impinging the beam perpendicular to the fiber's axis as illustrated in the diagram in FIG. 5 . In the exemplary embodiment illustrated in FIG. 5 , a beam 34 from a CO 2 laser 36 is split with beam splitters 38 , 40 toward mirrors 42 - 48 , which are used to direct the split beams 50 , 52 toward a common spot 54 through ZnSe optics 56 - 60 to obtain a circular spot 54 size of approximately 1.4 mm in diameter. Additional components such as a beam blocker 62 , detector 64 , and additional mirrors 66 may also be used in the configuration. It will be appreciated that other laser configurations and types may be employed. Additionally, spot sizes may be adjusted to accommodate the diameters and sizes of the green fibers 32 . The green fiber 32 travels through the beam's spot 54 such that sintering times are approximately one minute, though sintering times may vary again based on the diameters and sizes of the green fibers 32 .
One or more continuous wave lasers may be utilized in other embodiments, such as those illustrated in the schematic diagrams of FIGS. 6 and 7 . Multiple lasers 68 - 72 may be used in place of the optics of FIG. 5 as seen in FIG. 6 , or the majority of the optics may be eliminated with a single laser 36 configuration as illustrated in the schematic in FIG. 7 . Alternatively other methods may be employed, such as configurations used with laser heated pedestal growth as illustrated in the schematic diagram in FIG. 8 where laser 36 directs a beam to axicon 74 generating a circular pattern 76 . The circular beam pattern 76 may be reflected off of reflecting mirror 78 , in some embodiments, toward a focusing mirror 80 , which focuses the circular pattern 76 on the beam spot 54 in order to sinter fiber 32 . The configuration just described is similar to that used by Laser Heated Pedestal Growth (LHPG) for growing single crystal fibers. While the LHPG configuration is usually used to melt the material in order to create a single crystal, in embodiments of the invention where the lasers are used for sintering, the temperature of the beam spot 54 in FIG. 8 is always kept below the melting point of the fiber 32 , but hot enough for the sintering process. Lasers other than continuous wave lasers may also be used depending on the composition of the green fibers and the ceramics used, such as lutetia, YAG, Scandia, or Yttria, for example. The sintering process results in fibers that are better than 99 percent dense with impurities on the order of parts per million, which assists in reducing scatter and loss.
Since the green fiber 32 is being moved through the laser spot 54 , the components set forth above may be used together in order to form a continuous YAG fiber, rather than fibers of set length. Turning now to the embodiment illustrated in the schematic diagram in FIG. 9 , the process again begins with a YAG slurry 16 , which as set forth above may consist of YAG nanopower 10 , a binder 12 , and a liquid 14 . The slurry may then be fed into the extruder 18 which extrudes a green fiber 22 from die 20 . As set forth above, the diameter of the green fiber may be determined based on the die, which also affects the extrusion pressure. The green fiber 22 may then be sent through a processing chamber 30 to remove any of the fluid or binder materials. Processing chamber 30 may be a single chamber or multiple chambers depending on the requirements for eliminating both the liquid and binding agent. After passing through the processing chamber 30 , the green fiber 32 may then be directed through the laser spot 54 for sintering. The laser configuration may include any number of lasers and appropriate optics as discussed above. The resulting sintered YAG fiber 82 may then coiled or otherwise cut to desired lengths for laser and other applications utilizing optical fibers.
In an alternate embodiment for continuous extrusion, as illustrated in the schematic diagram of FIG. 10 , the process again begins with a YAG slurry 16 , which as set forth above may consist of YAG nanopower 10 , a binder 12 , and a liquid 14 . The slurry may then be fed into the extruder 18 which extrudes a green fiber 22 from die 20 . As set forth above with the other embodiment, the diameter of the green fiber may be determined based on the die, which also affects the extrusion pressure. The green fiber 22 may then be passed through a first laser spot 84 produced by a first laser 86 using appropriate optics 88 . This first laser 86 may be used in place of the processing chamber 30 in the embodiment above, calcining the fiber 22 eliminating both the liquid and binding agent, though other embodiments may employ a combination of a processing chamber 30 and the first laser 86 . After passing through the first laser spot 84 , the green fiber 32 may then be directed through a second laser spot 90 for sintering. The second laser spot 90 may be produced by a second laser 92 using appropriate optics 94 . In other variations of this embodiment, either of the laser configurations may include any number of lasers and appropriate optics as discussed above. The resulting sintered YAG fiber 82 may then be coiled or otherwise cut to desired lengths for laser and other applications utilizing optical fibers.
While the present invention has been illustrated by a description of one or more embodiments thereof and while these embodiments have been described in considerable detail, they are not intended to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and method, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the scope of the general inventive concept. | A method and system for generating an optical fiber is provided. The method includes creating a green fiber consisting primarily of a ceramic material and sintering the green fiber with a laser by moving the green fiber through a beam of the laser to increase the density of the fiber after sintering. The system for creating a continuous optical fiber includes an extruder, a processing chamber and a laser. The extruder is configured to extrude a ceramic slurry as a green fiber. The processing chamber is configured to receive and process the green fiber. And, the laser is configured to direct a laser spot on the green fiber exiting the processing chamber to sinter the green fiber. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Provisional Patent Application Ser. No. 60/749,611, filed Dec. 13, 2005, the disclosure of which is hereby incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to systems and methods to process royalties based on existing information as soon as it becomes available. Sales records are processed on a transaction basis rather than in batch mode. This process also allows correction of information retroactively, rather than delaying the entire processing of the information.
2. Description of Related Art
Royalty management for audio and video content products is a very complex area. Recent years have witnessed a tremendous growth of audio and video product publishers, with new product labels springing up and old labels being acquired. These factors alone have made the management of royalties extremely complicated, but furthermore, the volume of product transactions has increased greatly and is expected to explode with the advent of new media and delivery methods, such as product file downloads, pay-per-listen, pay-per-view, etc. As a result, current batch-type processing of royalty earning calculations is badly bottlenecked and soon will be so inadequate to handle the volume of transactions that it will be unusable. If it takes more than 24 hours to process a batch that means that the batch cannot be processed daily and thus must be processed less frequently, typically weekly. And once the run time for a batch process exceeds seven days, the batch may only be processed once a month, and the resulting data will so out of date that it is useless. In particular, royalty data that is older than one month does not allow publishers to view sales activity within the month. The resulting data has only historic value, which makes it very hard for publishers and sales forces to react to changes in acquisitions and royalty income. An additional problem is that royalty rates often depend on the volume of either transactions, dollars, or both, and therefore, the more delays in the processing of this information, the more convoluted and problematic the batch processes are. Thus, the delays will be even greater.
Thus, a need exists for a new shared royalty platform (SRP) that allows real-time processing of royalties, based on existing information as soon as it becomes available.
SUMMARY OF THE INVENTION
The invention relates to systems and methods for processing royalties based on existing information as soon as it becomes available. A distinguishing characteristic of the present invention is its movement over time from state to state, progressing from milestone to milestone, supporting dynamic royalty calculation processes.
Sales records may be processed on a transaction basis rather than in batch mode. This process may also allow correction of information retroactively, rather than delaying the entire processing of the information.
One embodiment includes a system for royalty management comprising a message broker in communication with a plurality of clients and services, at least a first state machine in communication with the message broker, at least a first processor in communication with the message broker and a time manager in communication with the message broker. The message broker interacts with the at least first processor to execute at least a first common service based on events produced by the at least first state machine.
Another embodiment includes a method for royalty management comprising providing at least a first rate matrix, receiving a sales record from a database, loading the received sales record to a processor, publishing an initialization event message based on the sales record, activating a state machine with the initialization event message, transferring the state of the record, updating the state of the record in the database, validating the sales record, publishing a validation event message, activating the state machine with the validation event message, transferring the state of the record, updating the state of the record in the database, publishing a matching event message, matching the sales record with a product sales agreement and calculating a royalty payment using the matched sales record and the at least first rate matrix. Yet another embodiment includes validating a license on a product that is the subject of the product sales agreement.
As will be realized, this invention is capable of other and different embodiments, and its details are capable of modification in various obvious respects, all without departing from this invention. Accordingly, the drawings and descriptions are to be regarded as illustrative in nature and not as restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an overview of the environment of the shared royalty platform (SRP) in one embodiment of the present invention.
FIG. 2 shows an example of a product with related copyright obligations.
FIG. 3 shows an overview of the royalty calculation processes of the SRP.
FIG. 4 shows a top-level view of the interlinking of the SRP with the Repertoire Management System (RMS).
FIG. 5 shows a generic architecture of one embodiment that allows SRP to replace batch royalty calculation processes with a Royalty Calculation Process.
FIG. 6 is an illustration of the main SRP Royalty Calculation Process.
FIG. 7 shows an example of a State Machine.
FIG. 8 shows an example of a Rate Matrix (RM).
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an overview of the environment 100 of the shared royalty platform (SRP) 101 in one embodiment of the present invention. FIG. 1 shows that the SRP 101 may interact with four different business perspectives that correspond to different views on the royalty generation products from four worlds, and also that each of these four worlds have their own areas of overlap and interactions. There may be a Sales World 111 , which includes the business perspective from the sales and marketing side; and the Repertoire Owners' World 113 , which is mostly comprised of artists and rights holders. There may also be a Publishing/Licensing World 110 , which comprises the people producing and publishing the actual copyrighted works of art; and the Accounting World 112 , which is a fourth business perspective, and from the SRP point of view may be an accumulator of the royalty calculation results, which are royalty amounts with explanations and a keeper of the accounting information, such as accounts, and payee, for all royalty recipients. At the center of all these worlds is the SRP 101 interacting with all four worlds.
The typical product subject to processing by the SRP could be, for example, albums 120 a - n . Each album 120 a . . . n may contain multiple tracks. Some albums may be a compilation where each track is made by a different artist and may then have one common or multiple separate publishing ownerships. FIG. 2 shows an example of a product with related copyright obligations. An album 200 may have multiple tracks 201 a - n . Each track may have one or more recordings 202 a - n , and each recording may have one or more songs 203 a - n , or versions of a song, and each song may have one or more publishers 204 a - n and one or more writers 205 a - n who have royalty rights. In some cases details of the multiple songs within a track are shown. For example, Track 2 contains a medley of existing songs, so both Song 1 and Song 2 are shown. In other cases, such as Track 3 , a track contains a new song that is a cover of an existing song, so both songs and all their respective rights holders are shown. Track 4 comprises samples of songs from various tracks from other recordings, and again, all the songs and all their respective rights holders are shown. In general, a product can be considered as a composite object that is an unlimited hierarchy of multiple embedded components. As a result, the end product may have a very complicated royalty earnings calculation model.
The SRP may be designed following the principles of Service Oriented Architecture (SOA). In this architecture, services may be oriented around a message bus that is responsible for passing messages from one service to the next. A presentation layer may be responsible for creating task-oriented GUI for different types of users (business roles) of SRP.
An application layer may represent the business logic of the system. It may be based on a set of loosely coupled services whose orchestration and execution may be driven by a Finite State Machine-based business process model (BPM) engine. The BPM engine and the services may communicate with each other through a message broker using a publish/subscribe mechanism. In one embodiment, the message broker may be based on the Java Message Service (JMS) specification. Types of business logic in the SRP may include Declarative, which may be defined either as a Finite State Machine for major business entities that implement BPM engine or business rules-based, as implemented for Royalty Calculation Services; Procedural, which may be services that have straightforward logic that is not subject to change by business users and may be implemented by Java classes; and Workflow, which may control distribution and management of analysts' tasks and approval processes, as well as time management functions.
A data layer may provide the storage of information within the SRP. In one embodiment, operational data may be stored in databases containing data for royalty processing and reporting data may be stored in a different database for performance reasons. In one embodiment, the databases may use ORACLE PL/SQL technology. In one embodiment, data stored in files may be stored in XML format and SRP interfaces may use XML documents to represent data for transfer.
Instead of making the processors and other participants of the business processes aware of exactly which events to which they are subscribed and which events they publish, one embodiment of the invention moves this knowledge to special lightweight publishers/subscribers. Different combinations of these publisher/subscribers can specify a highly efficient batch processing. Whenever necessary, the clients, processors and state machines can play the roles of being their own publisher/subscribers.
Royalty calculations are the core of the SRP 101 . Most SRP business processes may be built around royalty calculation services, feeding them with sales data and royalty calculation rates from the contracts for all related royally recipients. Many intermediate events could happen before SRP decides that royalty calculation results are accurate and can be passed to the accounting system. FIG. 3 shows an overview of the royalty calculation processes 300 of the SRP 101 . In this embodiment, the flow Sales Information 301 triggers a flow of calculations in three paths, with data coming from the Repertoire Owners World 113 and the Publishing/Licensing World 110 . The first data path is Union Calculations 302 , drawn from Union Rates 303 . The second path is Artist Calculations 304 , drawn from Artist Rates 305 and Product Lifecycle Information 306 . The third path is Copyright Calculations 307 , drawn from Copyright Rates 308 and License Lifecycle Information 309 . The flow of data from these three paths combines into a stream of information that may be used to accumulate Royalty Earnings 310 in Accounting World 112 . The fact that not all information necessary for royalty calculations comes into the system at the same time adds an additional complexity and may force the SRP to make intermediate decisions, wait for information to become available, and then make recalculations.
The SRP 101 lives in a complex world communicating with other systems. In particular, it may receive all products and product updates from a Repertoire Management System (RMS) 401 . FIG. 4 shows one embodiment of a top-level view 400 of the interlinking of the SRP with the RMS, from which it may receive all products and product updates. The RMS may contain data about who owns rights to and who publishes each product. The RMS may interact with different aspects of the Publishing World 110 , including Manufacturing 110 a , Digital Partners 110 b , and SOP/WMS 110 c (SOP is an abbreviation for Sales Order Processing and WMS is an abbreviation for Warehouse Management System). The Repertoire Owners 423 may have stakes in the both the RMS and the SRP, as shown by the dotted line of Product Links 422 connecting those entities.
FIG. 5 presents a generic architecture of one embodiment that allows SRP to replace batch royalty calculation processes with one process, a Royalty Calculation Process that may be always active and processes sales records on a transaction basis rather than in batch mode. The Royalty Calculation Process may react to all system events using an event managing mechanism 500 . The Message Broker 530 may provide a generic event management mechanism with publish/subscribe facilities. Events may travel between clients (publishers/subscribers) in the form of messages. This allows different SRP clients, such as processors and state machines, to produce and consume system events, such as “new sales records came” or “a rate matrix has been changed.” Message Broker 530 may interact with Processors 521 a through 521 n to execute Common Services, such as a royalty calculation service, 520 a through 520 n based on events produced by State Machines 501 . The messages associated with events usually contain the event type, an object ID on which the event happened, and other event-specific information. SRP services, called Processors, may communicate using a publish/subscribe mechanism. They may be invoked when they receive messages to which they are subscribed that are emitted by the State Machines or by other Processors. They can also publish messages that can cause state transition or invocation of other Processors that subscribe to these mechanisms.
State Machines 501 through 505 a - n may be defined for all types (not instances) of business objects whose life cycles are maintained by SRP. They may specify process- or company-specific reactions to the state changes of the major SRP entities. SRP may maintain separate state machines for sales records, products, contracts, licenses, sub-ledgers, and other major entity types. State Machines may define and control how these objects change their states when certain events occur. State Machines may subscribe to receive all their events, and they may publish all their state transitions as events as well. A state machine may be envisioned as a table with a list of possible states as rows and a list of possible events as columns. Each cell may define how the proper event changes the proper state. A state machine may subscribe to receive all its events. At the same time, it may publish all state transitions that actually happened as other events. An example of a state machine is presented in FIG. 7 . The state machines may govern which pre- and post-processing logic is executed on every transition and what messages are emitted.
Time Manager 510 may be a special processor that is responsible for handling temporal events. Time Manager 510 may publish different temporal events at pre-defined time. Many SRP royalty calculation and reporting processes may be initiated on certain dates via the Time Manager. Time manager may also be subscribed to all SRP temporal events like “Delay this record calculation for 10 days” during which some missing copyright data can be provided. Process- or company-specific time delays are defined as temporal events. Use of the Time Manager 510 may allow the system to time-stamp events and may prevent events from being lost or overlooked.
FIG. 6 is a snapshot of one embodiment of the main SRP Royalty Calculation Process 600 described above. In this example, an initial Processor “Load” 603 may receive the sales records from database 602 and then publishes event “Initialize” 620 in Message Broker 530 . Message Broker 530 activates the State Machine “Sales Record” 601 , which is subscribed to this type of event. In this example, the State Machine 601 is further defined in FIG. 7 . State Machine 601 transfers the record from the state “New” to the state “Waiting for Validation,” makes the proper changes in the database 602 , and publishes a new event “A record is waiting for validation.” Message Broker 530 activates Processor “Validate” 604 which is subscribed to this type of events. Processor “Validate” 604 validates the content of the sales record and publishes a new event “Validated” with a parameter True or False. In this example, let us assume the validation was successful. Message Broker 530 again activates the State Machine 601 . State Machine 601 transfers the record from the state “Waiting for Validation” to the state “Waiting for Matching,” makes the proper changes in the database 602 , and publishes a new event “A record is waiting for matching.” Again, another Processor, for example, one that could be called “Match Record with Rate Matrix” that is subscribed to this event will be activated, and the process will continue until there are no events to handle.
Thus, the proposed architecture 500 may eliminate the need to run different royalty calculation processes on a daily, weekly, monthly or quarterly basis. Every royalty calculation process may be implemented as a sequence of special processors that are always running or waiting to run. The processors may be activated at any time when the related objects, such as sales records, contracts, licenses or rate matrices, are changed. Therefore, the resulting sub-ledgers in the Accounting World may always have the latest calculation results. The scheduled accrual and statements run may be initiated by the proper time events, and can merely summarize the latest calculation results already saved in sub-ledgers.
Business rules that define the royalty calculation logic may be expressed using various royalty keys and factors (rates) that implement the established policies of different repertoire owners. This logic is usually defined in contracts and licenses. SRP proposes a generic way to define, maintain and execute Rate Matrices (RM) that corresponds to the different contracts and licenses. The RM may specify the following, non-exclusive list of factors:
different royalty calculation factors
different combinations of royalty keys that specify conditions under which these royalty factors should be applied
calculation methods and algorithms that should be used to calculate royalties.
FIG. 8 shows an example of a rate matrix. The data may be broken down into Royalty Keys, such as medium, the product type, the price level, etc. Various different royalty streams may flow from each track of each item, and each separate entry in the record may have a different royalty allocation. Additionally, percentages for the artist, the copyright owners, and all other parties with some rights to the product may be added and layered on top, and the royalty rates may change depending on volume reached per time unit, such as albums per month or per year, or on total volume, or on geographical distribution, or any of many other variables.
Different SRP business processes at different points of time may launch the appropriate royalty calculation service. A business process may feed the service with the related sales data and may receive back from the service the calculated royalty amount or rejections with explanation on how it was calculated or why input was rejected. The service may use the corresponding RMs to do the actual calculation. While the calculation logic may reside inside each RM, the major service development efforts may be directed to a unified way to specify the service's input and output, bring the corresponding RMs to the picture and then efficiently execute them. A royalty calculation service may receive as input a record with sales-related information that may include sales information corresponding to a sales record, links to the associated contract/product/licenses and links to a specific execution environment, such as repertoire owner, seller, etc. A royalty calculation service may match the sales record with a product sales agreement and process the input record and related information to calculate the royalty amount. In one embodiment, a license on a product that is the subject of a product sales agreement may be validated as part of the process of royalty calculation and management. In one embodiment, there can be two types of processing results. The first, Positive, is where the service may return the calculated amount and, if requested, explanations of how this amount was calculated. The second, Negative, is where explanations are offered as to why the royalty cannot be calculated. A business process that launched this royalty calculation service may be able to interpret the results, making the process-specific changes in the major SRP repositories.
In one embodiment, a royalty payment is the amount due for a sales transaction based on the calculation method specified for the sales transaction and the calculation variables returned from the RM. In general, a default royalty can be calculated using the following generic formula: Royalty=Adjusted Units×Adjusted Base×Adjusted Rate. In one embodiment, the RM specifies the base, rate and unit values, and the adjustments for possible situations related to different types of products and sales. In one embodiment, the rules by which the calculation methods can be applied are not hard-coded, and can be configured or redefined directly inside RMs. At the same time, the default definition of the calculation methods can be used without requiring the attention of royalty analysts. The actual selection of the methods or algorithms can be done on the level of RM templates.
The above description is presented to enable a person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the preferred embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Thus, this invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein. | Systems and methods for the dynamic processing of royalties are disclosed. Sales records are processed on a transaction basis rather than in batch mode. This process also allows correction of information retroactively, rather than delaying the entire processing of the information. One embodiment includes a system comprising a message broker in communication with a plurality of clients and services, a state machine, a processor and a time manager. The message broker interacts with the processor to execute a common service based on events produced by the state machine. Another embodiment includes a method comprising providing a rate matrix, receiving a sales record from a database and calculating a royalty payment using the sales record and the rate matrix. | 6 |
RELATED APPLICATIONS
[0001] The present invention claims priority to co-pending U.S. Provisional Patent Application Ser. No. 61/526,320, filed 23 Aug. 2011.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to plow blades and particularly to guard attachments for the blade cutting edge. A traditional snow plow blade includes a cutting edge formed or attached at the lower edge of the plow blade. The function of the cutting edge is to scrape or cut through the snow or ice to remove them from the surface being plowed, such as a road or driveway. The cutting edge is traditionally formed from a hardened piece of steel and is typically attached to the lower edge of the plow blade by way of bolts or the like. Since cutting edges wear over time and need to be replaced, the cutting edge is preferably attached to the plow blade in a manner that permits facile removal. Thus the cutting edge can be replaced as needed while the rest of the plow blade, which is subject to much less wear, has a longer life span.
[0003] A typical cutting edge is somewhat sharp and therefore will tend to cut or dig into surfaces that are not sufficiently hard. For example, if the snowplow is used on a grassy surface or dirt surface, the cutting edge will cut into the grass or dirt and thereby damage the surface. A similar result may occur when the plow is used on a gravel surface. When used on a gravel surface, a typical cutting edge will tend to push the loose gravel, along with the snow, along the plow path. In these situations, subsequent repair of the grass, dirt or gravel is required due to damage done by a typical plow cutting edge.
[0004] Standard cutting edges have also been known to damage surfaces made from brick or paver blocks since the relatively sharp cutting edge has a tendency to chip or break the bricks and blocks. Further, if a surface to be plowed has been coated with paint or an epoxy coating, which is common in parking structures, the plow cutting edge is likely to scrape the paint or coating from the surface. Additional damage may be done to surfaces having speed-bumps or similar structures since the cutting edge is likely to damage these structures as well.
[0005] Plow damage to the mentioned environments is costly to repair and further add to annual grounds maintenance since the repairs must be repeated annually after the end of each plowing season. Therefore, there is a need for a device for use in conjunction with a plow blade that will enable the plow to be used in the mentioned plow environments without creating damage to the plowed environment.
SUMMARY OF THE INVENTION
[0006] The present invention allows the user to plow a path on diverse paved or non-paved surfaces without causing damage to the plow, vehicle equipment, or to the ground surface. The present invention includes a removable plow blade guard having a unique, rounded cross section to therefore allow it and the attached plow to glide across a variety of terrains or obstacles such as rocks or bumps without damage to the underlying terrain. The invention is adapted to fit most manufactured plows and to be easily attached and removed by one individual.
[0007] The invention can be fabricated in a variety of sizes to meet user needs. It may be used in conjunction with residential snowplows, commercial snowplows, split plows, wing plows, all terrain vehicle snowplows, tractor plows, and grader blades.
[0008] The blade guard of the present invention preferably includes a tubular member having an elongated open slot formed along its top surface. Optional end caps may be attached at each end of the member. One or more handles may be affixed along the outer surface of the tubular member.
[0009] A pair of brackets may be attached to the outer surface of the tubular member with the first end of a chain being connected to each bracket. A buckle or clamp may be connected to the opposite end of each chain.
[0010] In use, a plow blade and cutting edge to be used in conjunction with the invention is inserted into the elongated slot. The blade guard is then secured to the plow blade by way of a chain and clamp arrangement which is adapted to attach to an upper portion of the plow blade and/or its frame. The invention can be easily attached by one individual and removed by one individual. One or more handles are attached in locations along the tubular member for easy installation and removal.
[0011] The benefit to the user includes the ability to plow a path through the snow using existing plow equipment without causing damage to the plow equipment or the ground surface. This ability allows the user to access areas of property once unavailable during snow cover. Examples of difficult to plow residential areas include: paths to barns or outbuildings during winter months, or access to livestock pens or farm fields. The invention also allows the user to clear snow from the terrain when the ground is not frozen during early winter and spring months by lessening damage to grassy areas and avoiding time-consuming and costly repairs to the property. Some commercial applications of the invention include use on snowplows used to plow lots with speed bumps, or use on municipal plows having wing plows. Use of the invention on wing plows helps avoid moving gravel on the shoulder of the road or damage to grassy shoulder areas. In addition, the invention may be used on gravel or dirt roadways. The novel blade guard can be used on all terrain vehicles as well as garden or lawn tractors to create a variety of paths for a variety of needs. Residential users can use the invention to plow custom driveways, brick driveways or patios. States and governmental agencies can utilize the device in parts of the United States or Canada with unpaved roadways without causing damage to the ground surface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a perspective view of a device according to the present invention.
[0013] FIG. 2 is another perspective view of the present invention.
[0014] FIG. 3 is a perspective view of the invention attached to a traditional snow plow.
[0015] FIG. 4 is a fragmentary side perspective view showing the device attached to a plow.
[0016] FIG. 5 is a cross sectional view of the invention as illustrated in FIG. 3 and taken along lines 5 - 5 thereof.
[0017] FIGS. 6A-6C illustrate a method of attaching the device to a plow blade.
[0018] FIG. 7 is a perspective view of an alternative embodiment and illustrating a clamp, chain and bracket with the device engaged with a plow blade.
[0019] FIGS. 8A-8C illustrate a method of attaching the device illustrated in FIG. 7 to a plow blade.
[0020] FIG. 9 is a side view showing an embodiment having an alternative attachment means.
[0021] FIGS. 10A and 10B illustrate the device in use while in place on a plow blade.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0022] Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structures. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.
[0023] With reference now to FIG. 1 , a plow blade guard 10 according to the present invention may be seen. As illustrated, the guard 10 preferably includes a tubular member 12 having a tubular member top surface 14 and a tubular member bottom surface 16 . As seen, an elongated open slot 18 may be formed along the tubular member top surface 14 . The guard 10 may further include end caps 20 at each end 22 of the tubular member 12 , although FIGS. 5 , 6 , and 8 A- 10 B illustrate the invention with end caps 20 removed for ease of viewing. Further, one or more handles 24 may be affixed along an outer surface 26 of the tubular member 12 . The handles 24 aid the user in attaching and detaching the guard 10 from a selected plow blade 28 , as will be discussed in detail.
[0024] With further reference to FIGS. 1 , 2 , and 4 , it may be seen that the plow guard 10 preferably includes attachment means to further secure the blade guard 10 to a selected plow blade 28 . The attachment illustrated in FIGS. 1-6C preferably includes a pair of brackets 30 A, 30 B. As seen, the brackets 30 A, 30 B may be attached to the outer surface 26 of the tubular member 12 by welding or other secure means. Each bracket 30 A, 30 B may include at least one pin aperture 32 for receipt of a link pin 34 therethrough. As seen particularly in the view of FIG. 4 , the pin is adapted to engage a first end 36 of a chain member 38 . The number of pin apertures 32 may vary according the specific application and as desired to provide a variety of link pin 34 positioning points. The ability to position the chain member 38 at various locations along a selected bracket 30 A, 30 B allows the user flexibility in the tension adjustment and angle of the chain 38 length.
[0025] With reference now to FIGS. 1 , 4 , and 6 A- 6 C, a buckle or clamp 40 may be seen. Clamp 40 is connected to an opposite, second end 42 of each chain 38 by way of a clamp bracket 44 . As illustrated, the clamp 40 may be a toggle type clamp, such as the latch action toggle clamp shown. The clamp 40 may include a handle member 46 and U-bolt portion 48 . In use, the U bolt portion 48 is adapted to engage an upstanding latch 50 on latch plate bracket 52 . Clamps 40 for use with the present invention may include latch action toggle clamps such as those manufactured by Carr Lane Manufacturing Company or De-Sta-Co, by way of non-limiting example. As viewed particularly in FIG. 6A-6C , a latch plate bracket 52 may be attached to an upper edge 54 of plow blade 28 through use of the bolt 56 arrangement shown or other suitable means.
[0026] With particular attention to FIGS. 6A-6C , attachment of the blade guard 10 to a selected plow blade 28 may be seen. As illustrated, the plow blade 28 , including a cutting edge 58 is inserted into the elongated slot 18 in the direction of arrow A. The blade guard 10 is then secured to the plow blade 28 by way of a chain 38 and clamp 40 , each of which is respectively attached to an upper portion 54 of the plow blade 28 by latch plate bracket 52 and upstanding latch 50 . As shown, the u-bolt portion 48 of the toggle clamp 40 engages the upstanding latch 50 . The handle 46 of the toggle clamp 40 is then rotated in the direction of arrow B wherein a clamping force locks the blade guard 10 on the plow 28 cutting edge 58 . The blade guard 10 may be further provided with rod members 60 (see particularly FIG. 5 ) extending longitudinally along portion of the inside surface 62 of tubular member 12 . The rod members 60 provide further stability and aid in secure attachment of the guard 10 to a plow blade 28 . Other stability measures may include the use of additional strapping, such as the bungee cords 64 shown, to thereby prevent plow jostling during use to move the toggle handles 46 to an unlatched position and thereby inadvertently release the guard 10 from the blade 28 .
[0027] With reference now to FIG. 7 , an alternative embodiment of the blade guard 100 may be seen. Similar to the embodiment shown in FIGS. 1-6C , the blade guard 100 illustrated in FIG. 7 includes a tubular member 12 having a tubular member top surface 14 and a tubular member bottom surface 16 . As seen, the blade guard 100 further includes an elongated open slot 18 which is formed along the tubular member top surface 14 . One or more handles 24 may be affixed along an outer surface 26 of the tubular member 12 to aid the user in maneuvering and placing the blade guard 100 on a selected plow blade 28 . The blade guard 100 shown in FIG. 7 further includes attachment means to secure the blade guard 100 to a selected plow blade 28 . The attachment illustrated in FIG. 7 , similar to that of the blade guard 10 illustrated in FIGS. 1-6C , preferably includes a pair of brackets 30 A, 30 B. The brackets 30 A, 30 B may be attached to the outer surface 26 of the tubular member 12 by welding or other secure means. As does the blade guard 10 , each bracket 30 A, 30 B of the blade guard 100 may include at least one pin aperture 32 for receipt of a link pin 34 therethrough. The link pin 34 is adapted to engage a first end 36 of a chain member 38 , with each chain member 38 being connected to a respective bracket 30 a, 30 b. As may be further seen, a buckle or clamp 40 is connected to the opposite, second end 42 of each chain 38 . As illustrated, the clamp 40 may be a toggle type clamp, such as the latch action toggle clamp shown, and include a handle member 46 and a u-bolt portion 48 , the u-bolt portion 48 being attached to a link of the chain 38 . In the embodiment shown in FIG. 7 , the clamp bracket 144 of clamp 40 includes an angled edge 66 adapted to fit over and engage an upper support edge 70 of blade member 28 .
[0028] With particular attention to FIGS. 8A-8C , attachment of the blade guard 100 to a selected plow blade 28 may be seen. Similar to the device illustrated in FIGS. 6A-6C , the plow blade 28 , including a cutting edge 58 is inserted into the elongated slot 18 in the direction of arrow A. The blade guard 100 is then secured to the plow blade 28 by chain 38 and clamp 40 , each of which is respectively attached to an upper support edge 70 of the plow blade 28 by engagement of the angled edge 66 of clamp bracket 144 and the upper support edge 70 . As shown, the u-bolt portion 48 of the toggle clamp 40 engages the second end 42 of chain 38 . Unlike the installation shown in FIG. 6A-6C , the handle 46 of the toggle clamp 40 is then rotated in the direction of arrow C wherein a clamping force engages the angled edge 66 and upper support edge 70 , thereby locking the blade guard 100 on the plow 28 cutting edge 58 . The blade guard 100 may be further provided with rod members 60 extending longitudinally along portion of the inside surface 62 of tubular member 12 to provide further stability and aid in secure attachment of the guard 100 to a plow blade 28 .
[0029] With reference now to FIG. 9 , an alternative embodiment of the blade guard 200 may be seen. Similar to the embodiments shown in FIGS. 1-8C , the blade guard 200 illustrated in FIG. 9 includes a tubular member 12 having a tubular member top surface 14 and a tubular member bottom surface 16 . As seen, the blade guard 200 further includes an elongated open slot 18 which is formed along the tubular member top surface 14 . One or more handles 24 may be affixed along an outer surface 26 of the tubular member 12 to aid the user in maneuvering and placing the blade guard 200 on a selected plow blade 28 . The blade guard 200 shown in FIG. 9 further includes alternative attachment means to secure the blade guard 200 to a selected plow blade 28 . The attachment illustrated in FIG. 9 preferably includes a screw 68 , or other like device, that is adapted to pinch the tubular member 12 and rod 60 to thereby engage the guard 200 with the plow blade cutting edge 58 . The blade guard 200 may be further provided with rod members 60 extending longitudinally along portion of the inside surface 62 of tubular member 12 to provide further stability and aid in secure attachment of the guard 200 to a plow blade 28 .
[0030] The present invention further includes a method of plowing a selected surface 72 (see FIGS. 10A , 10 B) including the steps of attaching a plow guard 10 , 100 , 200 to the lower edge of a plow blade 28 , plowing a surface and removing the plow guard 10 , 100 , 200 . More specifically, a method may include the steps of:
[0031] providing a plow blade 28 having an upper edge 54 and a lower edge; providing a plow blade guard 10 , the plow blade guard 10 having a tubular member 12 , the tubular member 12 including a tubular member top surface 14 , a tubular member bottom surface 16 , and an inside surface 62 , the tubular member top surface 14 further including an elongated open slot 18 formed therein, the tubular member bottom surface including at least one bracket member 30 A, 30 B, an attachment mechanism, the attachment mechanism including at least one chain member 38 and at least one clamp member 40 ;
[0032] inserting the lower edge of the plow blade 28 into the elongated slot 18 ;
[0033] attaching at least one latch plate bracket 52 to an upper edge 54 of the plow blade 28 ;
[0034] attaching a first end 36 of the at least one chain member 38 to the at least one bracket member 30 A, 30 B;
[0035] attaching a second end 42 of the at least one chain member 38 to the at least one clamp member 40 ;
[0036] clamping the clamp member 40 to the at least one latch plate bracket 52 ; and
[0037] plowing a selected surface with the plow blade 28 and attached plow blade guard 10 .
[0038] An alternative method may include the steps of:
[0039] providing a plow blade 28 having an upper edge 54 and a lower edge; providing a plow blade guard 100 the plow blade guard 100 having a tubular member 12 , the tubular member 12 including a tubular member top surface 14 , a tubular member bottom surface 16 , and an inside surface 62 ; the tubular member top surface 14 further including an elongated open slot 18 formed therein; the tubular member bottom surface including at least one bracket member 30 A, 30 B; an attachment mechanism, the attachment mechanism including at least one chain member 38 , at least one clamp member 40 having a rotatable handle 46 , and a least one clamp bracket 144 ;
[0040] inserting the lower edge of the plow blade 28 into the elongated slot 18 ;
[0041] attaching a first end 36 of the at least one chain member 38 to the at least one bracket member 30 A, 30 B;
[0042] attaching a second end 42 of the at least one chain member 38 to the at least one clamp member 40 ;
[0043] attaching the at least one clamp bracket 144 to an upper support edge 70 of the plow blade 28 ;
[0044] rotating the handle 46 of the clamp member 44 to thereby clamp the clamp bracket 144 and tubular member 12 to the plow blade 28 ; and
[0045] plowing a selected surface with the plow blade 28 and attached plow blade guard 100 .
[0046] A method may further include the step of providing the tubular member 14 with at least one handle.
[0047] A method may further include the step of providing the tubular member 14 inside surface 62 with at least one rod member 60 extending longitudinally along portion of the inside surface 62 .
[0048] The foregoing is considered as illustrative only of the principles of the invention. Furthermore, 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. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims. | A plow blade guard adapted for attachment to a selected plow blade and method of use is disclosed. The plow blade guard includes an elongated tubular member having an elongated slot formed along its length, the elongated slot is adapted to receive the cutting edge or lower edge of a selected plow blade. The plow blade guard is held place by brackets, chains and clamps. The guard may include handles to facilitate installation and removal. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from commonly owned U.S. Provisional Patent Applications 60/306,155, titled SYSTEM AND METHOD FOR MULTIDIMENSIONAL DATA COMPRESSION, 60/306,188, titled SYSTEM AND METHOD FOR VIRTUAL PACKET REASSEMBLY and 60/306,193, titled SYSTEM AND METHOD FOR STRING FILTERING all of which were filed on Jul. 17, 2001 and are presently pending, and are hereby incorporated by reference in their entirety.
CROSS-RELATED APPLICATIONS
[0002] This application is related to utility patent applications U.S. application Ser. No. ______ (Atty. Docket No. 1956-2-3) titled SYSTEM AND METHOD FOR STRING FILTERING and U.S. application Ser. No. ______ (Atty. Docket No. 1956-1-3) titled SYSTEM AND METHOD FOR VIRTUAL PACKET REASSEMBLY, which were filed on the same day as this application and which are hereby incorporated by reference in their entirety.
TECHNICAL FIELD OF THE INVENTION
[0003] The present invention relates generally to signal processing systems and methods in which multiple types of data are processed to arrive at an outcome. The present invention may comprise a system and method for generating compressed representations of data packets, and for processing such compressed data packet representations to perform packet and/or header filtering operations.
BACKGROUND OF THE INVENTION
[0004] Multidimensional data comprises multiple types of information upon which particular processing sequences may be performed to arrive at a given outcome. Portions of such processing sequences may be dependent upon the characteristics of constituent information within the multidimensional data itself. Examples of multidimensional data include vectors, informational databases, and mathematic matrices.
[0005] One type of multidimensional data is a networking datagram or packet. A packet comprises a self-contained messaging unit having fields specified or defined in accordance with one or more network transport protocols, for example, Transmission Control Protocol in conjunction with the Internet Protocol (TCP/IP). Particular fields may be reserved for source and/or destination routing information, while other fields may be reserved for data content. The routing information is sufficient to enable elements within a transporting network to deliver the packet to a target destination.
[0006] Packets flowing upon a computer network, and/or flowing from one computer network to another, may contain information directed toward compromising network security and/or performing malicious or destructive operations upon one or more computer systems. Such packets are typically associated with an attempted hacker intrusion.
[0007] An Intrusion Detection System (IDS) comprises software that performs packet filtering operations. During packet filtering operations, the IDS examines packets flowing upon a computer network, and determines whether any given packet exhibits characteristics associated with known types of network intrusions and/or hacker attacks. The packet filtering operations may include header filtering operations directed toward examining packet headers; and string filtering operations directed toward examining packet data content.
[0008] In header filtering operations, an IDS compares various field values within a protocol header with values associated with known hacker attacks, commonly referred to as attack signatures. Unfortunately, hacker attacks may span multiple fields, where field values may be combined as Boolean expressions, thereby complicating header filtering operations. Furthermore, hundreds of known hacker attacks exist, and thus an IDS may need to examine thousands of field value combinations to accurately determine whether a given packet or packet sequence corresponds to an attack signature.
[0009] Traditional packet filtering systems and methods typically rely upon tree search algorithms, in which a result of a given field value test narrows a number of possible attack signatures for subsequent consideration. However, such tree search algorithms are performed serially, and are therefore significantly slower than desired. Moreover, their performance degrades as additional attack signatures are discovered.
[0010] An additional problem arises because modern networks continue to evolve toward ever-higher data transfer rates. For example, high speed Local Area Networks (LANs) may operate at 1000 Megabits per second (Mbits/sec). Similarly, internet access points commonly operate at 155 Mbits/sec and 622 Mbits/sec; higher operating speeds are likely in the future. Present day systems and methods for packet filtering and/or network intrusion detection are capable of examining only a fraction of the packets traversing such networks, thereby significantly limiting their usefulness. There exists no present day IDS capable of providing adequate packet filtering in high-speed network environments exists.
SUMMARY OF THE INVENTION
[0011] An embodiment of the present invention is directed to a computer-based method and system for performing header filtering of data. The method comprises compressing the header of a data packet to obtain a header signature and determining if the header signature matches a known header signature. If the header signature is determined to have a match, then the header signature is identified as a known header signature. A header signature may be generated using a multidimensional data compression algorithm.
[0012] In another embodiment of the invention, a compression algorithm comprises obtaining the data bits contained in each field of a typical header. Then, a header-field group that corresponds uniquely to each field is determined. Each field is replaced with the header-field group of the corresponding data bits of the field and concatenated to create a header signature.
[0013] In contrast to prior systems and methods, the multidimensional data compression provided by the above-described embodiments of the invention eliminates the need to rely upon slow and/or inefficient tree search algorithms. Additionally, these embodiments may be characterized by the generation of a header signature via a constant or essentially constant number of operations. As a number of known signatures associated with hacker attacks increases, the sizes of one or more header-field groups may increase, yet the number of operations required to perform header or packet filtering may remain unchanged. Furthermore, these embodiments may be implemented using hardware. As a result, these embodiments are well-suited for providing packet filtering in high-speed network environments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] [0014]FIG. 1 is a block diagram of a system incorporating hardware and/or software elements for implementing or performing header filtering operations in accordance with an embodiment of the invention.
[0015] [0015]FIG. 2 is a flowchart of a method for performing header filtering operations in accordance with an embodiment of the invention.
[0016] [0016]FIG. 3 is a lookup table addressed in accordance with signature values and storing associated processing outcomes corresponding to a compression of exemplary multidimensional size and color data in accordance with an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0017] The following discussion is presented to enable a person skilled in the art to make and use the invention. The general principles described herein may be applied to embodiments and applications other than those detailed below without departing from the spirit and scope of the present invention. The present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed or suggested herein.
[0018] Embodiments of the present invention may be applied in the context of header filtering for the purpose of network-intrusion detection. But the following description is not intended to limit the use of the invention in other applications that use header filtering, such as word processors, signal processors, and/or database management tools.
[0019] [0019]FIG. 1 is a block diagram of a system 100 for header filtering constructed in accordance with an embodiment of the invention. The system 100 may be part of an overall Intrusion Detection System (IDS). The system 100 may comprise a processing unit 102 , an input/output unit 104 , a data storage unit 106 , a display device 108 , a system memory 120 , and a network-interface unit 130 , each of which may be coupled to a common bus 190 .
[0020] The network-interface unit 130 may interface the system 100 to a computer network upon which packet-filtering operations are required. The network-interface unit 130 may comprise conventional network communication or interface elements, as well as a packet-filtering unit 140 and an associated lookup table 150 constructed and/or operating in accordance with an embodiment of the invention. The lookup table 150 may reside in a local memory (not shown) on the network-interface unit 130 or in the system memory 120 . The network interface unit 130 may serve as an interface between the system 100 and a network upon which packet-filtering operations are required. The packet filtering unit 140 may comprise a state machine coupled to the lookup table 150 and/or the system memory 120 . One or more sequences of program instruction sets residing in the system memory 120 and executable by the processing unit 102 may operate in conjunction with and/or support operations performed by the packet filtering unit 140 . In an exemplary embodiment, the state machine may be implemented using a Field Programmable Gate Array (FPGA).
[0021] The packet-filtering unit 140 , in conjunction with the lookup table 150 , may perform two filtering operations. The first filtering operation performs header filtering of each data packet received which is described in detail below. The second filtering operation performs string filtering of the payload of each data packet received. Various string filtering operations of payloads are well known to those in the art and will not be described further herein.
[0022] An IDS constructed or implemented in accordance with the present invention may operate in a variety of network environments. For example, an IDS capable of performing header or packet filtering operations in a manner disclosed herein may monitor network traffic 1) within a LAN; 2) between a LAN and an external network such as the Internet, where the IDS may form a portion of a firewall system; or 3) between subnetworks within a system of networks.
[0023] There are several standard and well known protocols for data packet transmission a computer network. Examples include Internet Control Message Protocol (ICMP), User Datagram Protocol (UDP), and Transmission Control Protocol (TCP). These examples differ in the manner in which group identifiers may be combined to form ICMP, UDP, and TCP header signatures. Header signatures are compared to a list of known header signatures in the lookup table 150 to determine if a specific header signature is known to be from a malicious source. Each header signature, regardless of the protocol from which it was created spans 21 bits, and thus the lookup table 150 requires 2,097,152 (2 21 ) entries.
[0024] [0024]FIG. 2 is a flowchart of a method for performing header and/or packet filtering operations in accordance with an embodiment of the invention. The method may be performed via hardware and/or software. In one embodiment, the method may be performed and/or directed by a packet filtering unit 140 within a system 100 such as that shown in FIG. 1.
[0025] All data packets contain headers that have a plurality of groupings of data bits to indicate data-packet parameters such as, for example, source, destination, protocol, etc. of the data packet. The described method compresses, the header into a header signature. A header signature comprises a compressed representation of the data bits within a received data packet header. Typically, the header signature comprises a set of header-field groups appropriately generated in accordance with protocol type, as detailed below. The compression of data bits in field groups is known as multidimensional data compression. Multidimensional data compression will be described below after a general description of the overall method for generating a header signature.
[0026] A method for generating a header signature begins at step 200 where the packet-filtering unit 140 receives the entire header of a particular data packet.
[0027] Next, at step 202 , the packet-filtering unit 140 retrieves a destination Internet Protocol (IP) address as specified within the data-packet header which is typically 32 bits in length. Once retrieved, the destination IP address is compressed into a first header-field group which is typically 3 bits in length. In one embodiment, compression of the destination IP address into the first header-field group comprises a memory lookup operation using the lookup table 150 .
[0028] Next, at step 204 , the packet-filtering unit 140 retrieves a source Internet Protocol (IP) address as specified within the data-packet header which is also typically 32 bits in length. Once retrieved, the source IP address is compressed into a second header field group which is typically also 3 bits in length, in a manner analogous to step 202 . Compression of the source IP address into the second header-field group may also comprise a memory lookup operation using the lookup table 150 .
[0029] Next, at step 206 , the packet filtering unit 140 retrieves a transport protocol as specified within a data packet header which is typically 8-bits in length. Once retrieved, the transport protocol is compressed into a third header-field—field group which is typically 2 bits in length. Similarly, compression of the transport protocol into the third header-field group may also comprise a memory lookup operation such as that of the lookup table 150 .
[0030] At step 208 , a determination is made as to which particular protocol the data packet is using. In this embodiment, there are three possible protocol choices: ICMP, UDP, and TCP. Depending on which protocol is present, additional header-field groups may also be generated in the header signature by implementing a memory lookup operation using the lookup table 150 .
[0031] In the event that the protocol corresponds to TCP, the method moves to step 210 where a destination port address is retrieved and compressed into a fourth header-field group. Typically, the destination port address is 16 bits in length and compressed into 6 bits. Next, if the protocol is determined to be TCP, the method moves to step 212 where a source port address is retrieved and compressed into a fifth header-field group. Typically, the source port address is 16 bits in length and compressed into 7 bits. The method then moves to step 230 (described below) as the header signature has been assembled with five header-field groups for TCP.
[0032] In the event that the protocol corresponds to UDP, the method moves to step 214 and 216 . These steps are analogous to steps 210 and 212 for TCP protocol and generate a fourth and fifth header-group field as described above. Again, once the header signature for UDP has been assembled with five header-field groups the method then moves to step 230
[0033] In the event that the protocol corresponds to ICMP, the method moves to step 220 . At step 220 , a fourth header-field group may be generated by using the lookup table 150 . Two related sets of data bits are used to generate the fourth header-field group for ICMP. First, a set of bits corresponding to an ICMP type (typically 8-bits) is compressed into typically 3-bits. Second, a set of bits corresponding to an ICMP code (also typically 8-bits), is compressed into typically 3-bits. The method then moves to step 230 (described below) as the header signature has been assembled with four header-field groups for ICMP.
[0034] At step 230 , the newly created header signature is compared to known header signatures in the lookup table 150 . As was previously stated, the header signature comprises a compressed representation of information within a received data packet, and may comprise a set of header-field groups appropriately generated in accordance with protocol type, as detailed in steps 202 through 220 . Following any of steps 212 , 216 , or 220 , the header signature for a particular data packet has been completely assembled and a memory lookup operation is performed at step 230 . At step 240 , the lookup operation will return a threat code according to whether a match was determined in the lookup table 150 .
[0035] A threat code may comprise 1 byte and is an indication of whether no match has been determined, a match which requires further analysis has been determined, or a match which indicates a known header signature has been determined. Each threat code determines an outcome associated with or corresponding to a data packet. For example, if no match is found, the data packet is passed along to the system 100 from the network interface unit 130 . In direct contrast, if there is a definitive match, the data packet is captured and not allowed to pass to the system 100 . However, there may be many instances in which the method described above performed by the header filtering unit 140 alone may not determine a final outcome. For these cases, a signature group identifier may be returned as part of the threat code, which summarizes the results of the performed filtering method. Signature group identifiers may be similar to field group identifiers in that they are designed to retain all information necessary to support the header filter's contribution to a final outcome. The signature group identifier may be provided to a separate process (not described herein) that determines a final outcome.
[0036] Multidimensional data comprises multiple data elements that convey multiple types of information. Complex relationships between the data elements or portions thereof may exist. During multidimensional data processing operations, such relationships may require analysis to arrive at an outcome or result. In many situations, the number of possible outcomes may be quite limited, perhaps to a few or several choices.
[0037] As described above in one embodiment, multidimensional data is used to generate a corresponding header signature. The signature conveys all information necessary to determine the contribution that each data element within the uncompressed multidimensional data makes to a final outcome or result.
[0038] For example, a data element may have 65,536 possible values, but its final contribution may be to determine one of four possible outcomes. Each of the 65,536 possible values can be mapped into one of four possible groups, where the group determines one of the four possible outcomes. For example, in data processing terms, a 16-bit value can be represented by a 2-bit value, giving a compression ratio of 8:1.
[0039] Each data element within a multidimensional data set can be compressed in an analogous manner. The compression of each data element may be determined by a number of possible outcomes that it affects. The data can then be represented by a collection of groups that comprise the signature, which conveys all information necessary to determine a final outcome. Processing operations directed toward determining interrelationships between groups can be replaced with a simple lookup table operation, where the signature may be used as an index into the lookup table, and each table entry defines a final outcome. Complex relationships between data types may be defined in the programming of the lookup table.
[0040] The following example illustrates how two data types may be compressed in accordance with an embodiment of the present invention such that a single signature may correspond to six conditions resulting in one of four possible outcomes.
[0041] Data Elements:
[0042] a. size: 0,1, 2, . . . ,255
[0043] b. color: blue, brown, yellow, red, green, orange, black, white, purple,
[0044] i. salmon
[0045] Conditions:
[0046] c. Condition 1: If size=3 .AND. color=green, then Outcome 1
[0047] d. Condition 2: If size=7 .AND. color=(yellow .OR. black), then Outcome 2
[0048] e. Condition 3: If size!=100 .AND. color=blue, then Outcome 3
[0049] f. Condition 4: If size=(255 .OR. 34) .AND. color=black, then Outcome 1
[0050] g. Condition 5: If size=100 .OR. color=red, then Outcome 2
[0051] h. Condition 6: If none of the above, then Outcome 4
[0052] Each outcome in this example is the result of 5 unique sizes and 5 unique colors. The two data types may be grouped as follows:
[0053] Size grouping:
[0054] 3 belongs to Size Group 1 (S1)
[0055] 7 belongs to Size Group 2 (S2)
[0056] 255 belongs to Size Group 3 (S3)
[0057] 34 belongs to Size Group 4 (S4)
[0058] 100 belongs to Size Group 5 (S5)
[0059] All other sizes belong to Size Group 6 (S6)
[0060] Color grouping:
[0061] green belongs to Color Group 1 (C1)
[0062] yellow belongs to Color Group 2 (C2)
[0063] black belongs to Color Group 3 (C3)
[0064] blue belongs to Color Group 4 (C4)
[0065] red belongs to Color Group 5 (C5)
[0066] All other colors belong to Color Group 6 (C6)
[0067] Raw data in the form (size, color) may now be replaced by a compressed signature (S, C), where S and C are the group identifiers for the size and color data elements, respectively. The size group identifier has 6 possible values, and may therefore be represented by a 3-bit binary value. The color group identifier also has 6 possible values, and may therefore be represented by a 3-bit binary value. These two 3-bit values may be concatenated to form a 6-bit signature, with the size group identifier being the 3 most significant bits. The group identifier value assignments may be defined as follows:
a. S1 = = 0 C1 = = 0 b. S2 = = 1 C2 = = 1 c. S3 = = 2 C3 = = 2 d. S4 = = 3 C4 = = 3 e. S5 = = 4 C5 = = 4 f. S6 = = 5 C6 = = 5 g. not used = = 6 not used = = 6 h. not used = = 7 not used = = 7
[0068] A data set ( 100 , black) may be replaced with the signature ( 4 , 2 ) that has the 6-bit binary representation 100010 . A lookup table may be used to determine which condition a data set matches and what the outcome should be. The table may have as many entries as there are possible combinations of size and color groups. The signature in this example spans 6-bits, representing 64 possible combinations. Therefore, the lookup table includes 64 entries. The index into the lookup table comprises the signature value. Each entry in the table may be programmed with the outcome that corresponds to the group combination defined by the associated signature.
[0069] It may be the case that more than one signature represents a single filter condition. This may occur when “don't cares” or the Boolean operator “OR” appear in the filter condition. The filter condition outcome may be programmed into every table entry where the outcome signature satisfies the condition. For example, a filter condition that specifies only a color and no size has eight possible size values that can appear with the color that satisfy the condition. The condition's outcome may be programmed into all eight entries associated with the specified color.
[0070] [0070]FIG. 3 represents a lookup table 150 corresponding to the above example, addressed in accordance with signature values and storing associated processing outcomes corresponding to size and color data elements. The lookup table 150 is presented in the format “binary signature 300 : outcome/condition 302 ”. The condition number would not necessarily be entered into the lookup table 150 , but is shown to clarify which condition caused the outcome.
[0071] The raw data format in the example corresponding to FIG. 3 may be represented by a 12-bit uncompressed signature value, i.e., 8 bits to identify the size and 4 bits to identify the color. Such an uncompressed signature would require a lookup table 150 with 4,096 entries. This is a modest size that can be realized without compression. However, there are many applications in which a lookup table 150 would be so large that implementation without compression would not be feasible. | A computer-based method and system for performing header filtering of data is presented The method comprises compressing the header of a data packet to obtain a header signature and determining if the header signature matches a known header signature. If the header signature is determined to have a match, then the header signature is identified as a known header signature. A header signature may be generated using a multidimensional data compression algorithm. A compression algorithm comprises obtaining the data bits contained in each field of a typical header. Then, a header-field group that corresponds uniquely to each field is determined. Each field is replaced with the header-field group of the corresponding data bits of the field and concatenated to create a header signature. | 7 |
STATEMENT OF GOVERNMENT INTEREST
The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The present invention relates generally to the field of submarine simulators. In particular, it is a system for simulating the analog and digital inputs, outputs, or interfaces of submarine based sensor systems.
(2) Description of the Prior Art
Submarine simulators were developed many years ago to provide a realistic operating environment for training while minimizing the real hardware costs involved. These simulators have been constructed in a modular fashion, wherein one unit provides low level own ship sensor outputs. A second unit interprets these outputs and provides a realistic human interface for the operator. One example of this type of technology is the AN/BSY-1(V) Maintenance Trainer. The maintenance trainer relies upon a separate discreet Sensor Simulator Unit to provide low level ship sensor data, such that the trainer emulates deployed tactical hardware.
In the prior art, the low level ship sensor simulator has been an extremely computer intensive component. Because of this requirement, previous simulators have been based on the combination of mainframe computer hardware and software. Mainframe computer technology, first introduced in the 1960's, is expensive and unreliable due to the high degree of complexity of the computational architecture. Prior art ship sensor simulators have inherited these weaknesses from the technology upon which they are based.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an own ship sensor simulator capable of providing the sensor interfaces necessary for a submarine trainer.
It is a further object of the present invention to provide this system using low cost, high reliability components.
Another object of the present invention is to base the computing core of the system upon personal computer technology.
In accordance with the foregoing and other objects of the invention, a complete system for generating own ship sensor interfaces for a trainer is provided. The system provides own ship sensor interfaces from the following simulated devices: Ship Control Panel, Electrostatically Suspended Gyro Navigator, Gyrocompass, Periscopes, Ballast Control Panel, Depth Indicators, and Ship Radar. In addition, signals are provided for ship speed, bow plane angle, stern plane angle, and rudder angle. The simulator provides the system operator with an interface for monitoring and altering the sensor outputs.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing objects and other advantages of the present invention will be more fully understood from the following detailed description and reference to the appended drawings wherein:
FIG. 1 is a block diagram of the complete own ship sensor simulator system;
FIG. 2 is a block diagram of the components of each personal computer system in the system;
FIG. 3 is a circuit diagram of the digital input/output unit;
FIG. 4 is a table of the ship sensor signals provided by each component of the own ship sensor simulator;
FIG. 5 is a block diagram of the software modules of the own ship sensor simulator system;
FIG. 6 is a table of the sensor input configurable values provided by the man-machine interface module; and
FIG. 7 is a table of the sensor output values which can be monitored through the man-machine interface module.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, and in particular to FIG. 1, one embodiment is shown of the own ship sensor simulation system. The system comprises five computational engines 200, 300, 400, 500, and 600. In the preferred embodiment, five INTEL-80386 based single board computers are used. These personal computers are interconnected through an Internal Computer Network 100. This network allows the personal computers to exchange data and function as one integrated unit to provide own ship sensor signals to the external trainer unit through the output sensor lines 204, 206, 304, 306, 406, 412, 418, 424, 504, and 616. External input is accepted from the external trainer unit through input sensor lines 203, 205, 303, 305, 403, 409, 415, 421, 503, 506 and 615. Digital multiplexed input/output lines 603 and 606 drive digital input/output circuitry 700 which provides output and accepts input on bi-directional digital input/output lines 703, 706, 709, 712. Synchro multiplexed input/output lines 609 and 612 drive resolver to synchro converter 800 which provides synchro output and accepts synchro input through bi-directional synchro lines 803, 806, 809, and 812. The external trainer unit is not part of the present invention and is depicted in FIG. 1 only to show its relation to the present invention.
Referring now to FIG. 2, the internal configuration for each personal computer in the complete system is detailed. Personal computer 200 contains two Standard NATO Agreement (STANAG) interface cards. STANAG card 209 drives input line 203 and output line 204. STANAG card 212 drives input line 205 and output line 206. Personal computer 200 also contains single port communications card 215 which connects through Internal Computer Network 100 to personal computer 600.
Personal computer 300 contains two STANAG interface cards 309 and 312 which drive STANAG input line 303/output line 304 and STANAG input line 305/output line 306 respectively. Single port communications card 315 connects personal computer 300 to personal computer 600 through Internal Computer Network 100.
Personal computer 400 contains four Navy Tactical Data System (NTDS) interface cards 427, 430, 433, and 436. Each of these cards provides one input line and one output line with lines 403 and 406 being connected to card 427, lines 409 and 412 being connected to card 430, lines 415 and 418 being connected to card 433 and lines 421 and 424 being connected to card 436. Personal computer 400 is connected by single port communications card 439 through Internal Computer Network 100 to personal computer 600.
Personal computer 500 contains two STANAG interface cards 509 and 512 which drive STANAG input line 503 and output line 504 and STANAG input line 506. Single port communications card 515 provides connectivity through Internal Computer Network 100 to personal computer 600.
Personal computer 600 contains digital input/output card 618 which drives two multiplexed digital input/output lines 603 and 606. Personal computer 600 also contains two DIGITAL-SYNCHRO input/output cards 621 and 624 which drive synchro multiplexed input/output lines 609 and 612 respectively. A single STANAG interface card 627 drives STANAG input line 615/output line 616. Finally, cards are provided to communicate with all other personal computers in the system through Internal Computer Network 100. Two single port communication cards 630 and 633 interconnect to personal computers 200 and 300 respectively. A dual port communications card 636 interconnects to the remaining personal computers 400 and 500.
Referring now to FIG. 3, a circuit diagram of the digital input/output circuitry 700 is provided. Two multiplexed digital input/output lines 603 and 606 connect digital input/output circuitry 700 to the rest of the system. The purpose of this circuit is to simulate discreet analog switches contained in various submarine sensors. These two lines terminate on 24 channel output blocks 715 and 742. The output signals are jumpered from 24 channel output blocks 715 and 742 through output cabling 727 and 754 to output terminal blocks 733 and 757 on terminal connectors 730 and 772. Internally, terminal connector 730 connects output terminal block 733 to external terminal block 736. Digital I/O line 703 is directly connected to external terminal block 736. Internally, terminal connector 772 connects output terminal block 757 to each external terminal block 760, 763, and 766. Digital I/O lines 706, 709, and 712 are connected to external terminal blocks 760, 763, and 766 respectively.
Referring now to FIG. 4, the signals provided by each component in the complete system are summarized. Personal computer 200 provides Standard NATO Agreement Interface (STANAG) data input lines 203 and 205 and data output lines 204 and 206, simulating the own ship primary Indicator Drive Unit (IDU). Personal computer 300 provides STANAG data input lines 303 and 305 and data output lines 304 and 306 simulating the own ship secondary IDU. Input lines 203, 205, 303 and 305 accept input corresponding to the ship heading, speed, roll, pitch, plane/rudder angle, and bottom sound depth. Output lines 204, 206, 304 and 306, provide sensor outputs corresponding to the three strain gauge readings, processed depth, and ordered depth. Personal computer 400 provides Navy Tactical Data System (NTDS) input lines 403, 409, 415 and 421 and NTDS output lines 406, 412, 418 and 424. These eight lines simulate the inputs and outputs of the ship Electrostatically Suspended Gyro Navigation system (ESGN) to onboard ship's central computer (designated as the UYK-7 or UYK-43). The ESGN provides roll, pitch, heading, and speed signals to the trainer and accepts depth and synchronization inputs. Personal computer 500 provides two STANAG input lines. Input line 503 accepts input corresponding to ownship speed for the (WSN-2A) Gyrocompass. Output line 504 provides gyrocompass outputs corresponding to roll, pitch and heading. Input line 506 accepts input for the Electronic Depth Indicator. Personal computer 600 provides two multiplexed digital input/output lines 603 and 606, multiplexed synchro input/output lines 609 and 612, and STANAG input/output lines 615 and 616. The two multiplexed digital input/output lines 603 and 606 are divided into four digital input/output lines 703, 706, 709, and 712 by digital input/output circuitry 700. Digital I/O line 703 provides mast, bow, and radar mark sensor signals. Digital I/O line 706 provides periscope 18B mast, periscope 2F mast, and periscope 2F mark sensor signals. Digital I/O line 709 provides periscope 18B mark sensor signals. Finally, digital I/O line 712 provides EM LOG signals and rodmeter simulation. The two multiplexed synchro input/output lines 609 and 612 are divided into four synchro input/output lines 803, 806, 809, and 812 by resolver to synchro converter 800. Synchro I/O line 803 provides stern and rudder sensor signals. Synchro I/O line 806 provides the 2F1X, 36X, radar range and radar bearing signals. Synchro I/O line 809 provides bow and EM LOG 40 sensor signals. Synchro I/O line 812 provides the 18B1X, 36X, and EM LOG 100 sensor signals.
Referring now to FIG. 5, a block diagram of the software modules within the complete own ship sensor simulator system is provided. Flow of data is bi-directional from computer 600 to each secondary computer and on to its simulation. The arrows on the figure show the module that controls the passing and/or requesting of data from other modules within the data flow path. Each of the personal computers 200, 300, 400, 500, and 600 contain a software module responsible for reading and writing data across the internal computer network. These modules 227, 327 451, 527, and 648 execute the proper RS-232 network protocol and manages the message transfer across the RS-232 hardware interface. This data is retrieved by the primary managing software module within each computer where the data is properly interpreted and passed to the proper data repository region. Modules 230, 330, 454, and 530 control this function for computers 200, 300, 400 and 500 respectively. In computer 600, module 650 controls this function along with the man-machine interface functionality which allows the sensor input and output values for each component to be manually configured or monitored by an operator. Computer 600 also includes a network manager, software module 649, that codes or decodes the data for its final designation. The data repository regions are controlled by modules 233, 333,457, 533 and 653. These modules allow the dynamic simulations 240, 340, 460, 480, 540, 560, and 680 access to operator inputs and requests. Computer 600 manages the synchro analog signals through module 660 and digital switch signals through module 670. Computer 600 also simulates the WSN-2B gyrocompass via module 680. Module 680 contains two separate modules 683 and 685, that collectively manage the message traffic across a STANAG 4156 hardware interface: 683 receives input data and 685 sends output data. Modules 240 and 340 operate as an Indicator Drive Unit (IDU) within computer 200 and 300, respectively. These modules contain two modules (241 and 243) and (341 and 343) respectively that retrieve data from the trainer unit via STANAG 4156 interface cards. Modules 245 and 345 provide data to the trainer unit across the dynamically selected STANAG hardware interface. Computer 400 provides two identical ESGN dynamic simulations, modules 460 and 480. Modules 463, 465, 483 and 485 control the timing sequence inherent in an ESGN component. They alert their respective channel control modules 468, 469, 488, and 489 who manage the appropriate input/output data sequence from and to the trainer unit. Computer 500 provides a WSN-2A gyrocompass simulation via software module 540 and an Electronic Depth Indicator simulation via software module 560. Module 540 contains two separate modules 543 and 545, that collectively manage the message traffic across a STANAG 4156 hardware interface. Module 543 receives input data and module 545 sends output data. Module 560 reads the input data supplied to it by the trainer unit.
Referring now to FIG. 6, a table of the sensor input signals controlled by the man-machine interface module and their accepted values are detailed. Each of these values may be selected and manually set, independent of actual incoming data, through the man-machine interface. The man-machine interface can also be used to monitor the values of the output sensor data. The output sensor data is summarized in FIG. 7.
The STANAG, NTDS, DIGITAL I/O, and I/O cards are all standard personal computer cards readily available in the prior art, and do not comprise novel features of the present invention. The Resolver to Synchro Converter is readily available in the prior art and does not comprise a novel feature of the present invention. However, the placement and utilization of each of these components within the present invention represent novel features of the present invention. It will be understood that many additional changes in the details, materials, steps, and arrangement of parts, which have been herein described and illustrated in order to explain the nature of the invention may be made by those skilled in the art within the principal and scope of the invention as expressed in the appended claims. | A system for simulating own ship sensor outputs for submarine trainers is ovided. The system comprises of five personal computer systems operating together. These computers are interconnected such that the individual computers can exchange data and function as one integrated unit. The system provides sensor output to an external trainer through multiple STANAG, NTDS, DIGITAL™ I/O, and DIGITAL-SYNCHRO™ I/O cards. The system also accepts trainer inputs on these lines. Software modules on the personal computer systems allow the operator to configure and monitor the sensor systems as well as providing processing of inputs received at multiple sources to generate a coherent output signal. | 6 |
This application is a divisional of Ser. No. 09/995,593 filed Nov. 29, 2001, which is a divisional of Ser. No. 09/068,740 filed Jun. 18, 1998 now U.S. Pat. No. 6,337,387, which is the National Stage of PCT/JP96/03356 filed Nov. 15, 1996, which claims priority from Japanese Applications No. 7-299611 filed Nov. 17, 1995 and No. 7-311811 filed Nov. 30, 1995.
BACKGROUND OF THE INVENTION
This invention relates to a novel bioactive substance which suppresses differentiation of undifferentiated cells.
DESCRIPTION OF THE RELATED ART
Human blood and lymph contain various types of cells and each cell plays important roles. For example, the erythrocyte carries oxygen; platelets have hemostatic action; and lymphocytes prevent infection. These various cells originate from hematopoietic stem cells in the bone marrow. Recently, it has been clarified that the hematopoietic stem cells are differentiated to various blood cells Osteoclasts and mast cells by stimulation of various cytokines in vivo and environmental factors. In the cytokines, there have been found, for example, erythropoietin (EPO) for differentiation to erythrocytes; granulocyte colony stimulating factor (G-CSF) for differentiation to leukocytes; and platelet growth factor (mpl ligand) for differentiation to megakaryocytes which are platelet producing cells, and the former two have already been clinically applied.
The undifferentiated blood cells are generally classified into two groups consisting of blood precursor cells which are destined to differentiate to specific blood series and hematopoietic stem cells which have differentiation ability to all series and self-replication activity. The blood precursor cells can be identified by various colony assays. However, identification method for the hematopoietic stem cells have not been established. In these cells, stem cell factor (SCF), interleukin-3 (IL-3), granulocyte-macrophage colony stimulating factor (GM-CSF), interleukin-6 (IL-6), interleukin-1 (IL-1) granulocyte colony stimulating factor (G-CSF) and oncostatin M have been reported to stimulate cell differentiation and proliferation. Trials for expansion of hematopoietic stem cells in vitro have been examined in order to replace bone marrow transplantation for applying hematopoietic stem cell transplantation therapy or gene therapy. However, when the hematopoietic stem cells are cultured in the presence of the above mentioned cytokines, multi-differentiation activities and self-replication activities, which are originally in the position of the hematopoietic stem cells, gradually disappeared and are changed to the blood cell precursors which are only to differentiate to specific series after 5 weeks of cultivation, and multi-differentiation activity which is one of the specific features of the hematopoietic stem cells, is lost (Wagner et al., Blood 86. 512–523, 1995).
For proliferation of the blood precursor cells, a single cytokine is not sufficient, but the synergistic action of several cytokines are important. Consequently, in order to proliferate the hematopoietic stem cells while maintaining specific features of the hematopoietic stem cells, it is necessary to add cytokines which suppress differentiation together with the cytokines which proliferate and differentiate the undifferentiated blood cells. In general, may cytokines which stimulate proliferation or differentiation of cells are known, but small numbers of cytokines which suppressed cell differentiation are known. For example, leukemia inhibitory factor (LIF) has an action of proliferation of mouse embryonic stem cells without differentiation, but it has no action against the hematopoietic stem cells or blood precursor cells. Transforming growth factor (TGF-β) has suppressive action for proliferation against various cells, but no fixed actions against the hematopoietic stem cells or blood precursor cells.
Not only blood cells but also undifferentiated cells, especially stem cells, are thought to be involved in tissue regeneration. These regeneration of tissues and proliferation of undifferentiated cells in each tissue can be applied in various ways by referring to the known reference (Katsutoshi Yoshizato, Regeneration—a mechanism of regeneration, 1996, Yodosha Publ. Co.).
Notch is a receptor type membrane protein which is involved in regulation of nerve cells differentiation found in Drosophia . Homologues of the Notch are found in various animal kinds exceeding to the invertebrate and vertebrate including nematoda (Lin-12). Xenopus laevis (Xotch), mouse (Motch) or human (TAN-2). Ligand of the Notch in Drosophila are known. These are Drosophila Delta (Delta) and Drosophila Serrate (Serrate). Notch ligand homologues are found in various animal kinds as similar to the Notch of receptors (Artavanis-Tsakonas et al., Science 268, 225–232, 1995).
Human Notch homologue, TAN-1 is found widely in the tissues in vivo (Ellisen et al., Cell 66. 649–661, 1991). Two Notch analogous molecules other than TAN-1 are reported (Artavanis-Tsakonas et al., Science 268, 225–232, 1995). Expression of TAN-1 was also observed in CD34 positive cells in blood cells by PCR (Polymerase Chain Reaction) (Milner et al., Blood 83, 2057–2062, 1994). However, in relation to humans, gene cloning of human Delta and human Serrate, which are thought to be the Notch ligand, have not been reported.
In Drosophila Notch, binding with the ligand was studied and investigated in detail, and it was found that the Notch can be bound to the ligand with Ca** at the binding region, which is a repeated amino acid sequence No. 11 and No. 12 in the amino acid sequence repeat of Epidemal Growth Factor (EGF) like repeating (Fehon et al., Cell 61. 523–534, 1990, Rebay et al., ibid. 67, 687–699, 1991 and Japan. Patent PCT Unexam. Publ. 7-503123). EGF-like repeated sequences are conserved in Notch homologues of the other species. Consequently, the same mechanism in binding with ligand is estimated. An amino acid sequence which is called DSL (Delta-Serrate-Lag-2) near the amino acid terminal, and EGF-like repeated sequence as in the receptor are conserved in the ligand (Artavanis-Tsakonas et al.), Science 268, 225–232, 1995).
The sequence of DSL domain is not found except for the Notch ligand molecules, and is specific to Notch ligand molecule. A common sequence of DSL domain is shown in the sequence listing, SEQ ID NO: 1 in general formula, and comparison with human Delta-1 and human Serrate-1 of the present invention and known Notch ligand molecules are shown in FIG. 1 .
EGF-like sequence has been found in thrombomodulin (Jackman et al., Proc. Natl. Acad. Sci. USA 83, 8834–8838, 1986), low density lipoprotein (LDL) receptor (Russell et al., Cell 37, 577–585, 1984), and blood coagulating factor (Furie et al., Cell 53, 505–518, 1988), and is thought to play important roles in extracellular coagulation and adhesion.
Recently, the vertebrate homologues of the cloned Drosophila Delta were found in chicken (C-Delta-1) and Xenopus laevis (X-Delta-1), and it was reported that X-Delta-1 had acted through Notch in the generation of the protoneuron (Henrique et al., Nature 375, 787–790, 1995 and Chitnis et al., ibid. 375, 761–766, 1995). Vertebrate homologue of Drosophila Serrate was found in rat as rat Jagged (Jagged) (Lindsell et al., Cell 80, 909–917, 1995). According to the Lindsell et al., mRNA of the rat Jagged is detected in the spinal cord of fetal rats. As a result of cocultivation of a myoblast cell line is found. However, the rat Jagged has no action against the myoblast cell line without forced expression of the rat Notch.
Considering the above reports, the Notch and ligand thereof may be involved in the differentiation regulation of the nerve cells, however, except for some myoblast cells, their actions against cells including blood cells, especially primary cells, are unknown.
In the Notch ligand molecule, from the viewpoint of the prior studies on Drosophila and nematodae, the Notch ligand has specifically a structure of DSL domain which is not found other than in the Notch ligand. Consequently, the fact of having DSL domain means equivalent to ligand molecule for the Notch receptor.
SUMMARY AND OBJECTS OF THE INVENTION
As mentioned above, concerning undifferentiated cells, proliferation that maintains their specificies has not been achieved. Major reasons are that factors suppressing differentiation of the undifferentiated cells are not sufficiently known. An object of the present invention is to provide a compound originated from novel factors which can suppress differentiation of the undifferentiated cells.
We have set up a hypothesis that the Notch and its ligand have action of differential regulation not only for neuroblasts and myoblasts but also for various undifferentiated cells, especially blood undifferentiated cells. However, in case of clinical application in the humans, prior known different species such as chicken or Xenopus laevos type notch ligand have problems of species specificities and antigenicities. Consequently, to obtain previously unknown human Notch ligand is essentially required. We had an idea that a molecule having DSL domain and EGF-like domain which are common to Notch ligand molecules and a ligand of the human Notch (TAN-1 etc.), which is a human Delta Homologue (hereinafter designated as human Delta) and human Serrate homologue (hereinafter designated as human Serrate), may be found. Also we have an idea that these findings may be a candidate for drugs useful for differential regulation of the undifferentiated cells, and we have tried to find out the same.
In order to find out human Notch ligands, we have analyzed amino acid sequences which are conserved in animals other than humans, and tried to find out genes by PCR using mixed primers of the corresponding DNA sequence. As a result of extensive studies, we have succeeded in isolation of cDNAs coding amino acid sequences of two new molecules, novel human Delta-1 and novel human Serrate-1, and have prepared the expression systems of protein having various forms using these cDNAs. Also we have established purification method of the proteins which were purified and isolated.
Amino acid sequences of novel human Delta-1 are shown in the sequence listings, SEQ ID NO: 2–4. DNA sequence coding these sequence is shown in the sequence listing, SEQ ID NO: 8. Amino acid sequence of novel human Serrate-1 is shown in the sequence listings, SEQ ID NO: 5–7. DNA sequence coding these sequence is shown in the sequence listing. SEQ ID NO: 10.
Physiological actions of the these prepared proteins were searched by using nerve undifferentiated cells, preadipocytes, hepatocytes, myoblasts, skin undifferentiated cells, blood undifferentiated cells and immuno undifferentiated cells. As a result, we have found that novel human Delta-1 and novel human Serrate-1 had an action of differentiation-suppressive action to primary blood undifferentiated cells, and had a physiological action to maintain undifferentiated state.
Such actions to the blood undifferentiated cells have never been reported previously, and is a new discovery. No significant toxic actions were noted in the toxicity studies on mice, and useful pharmaceutical effects were suggested. Consequently, the pharmaceutical preparations containing the molecule of the present invention, medium containing the molecule of the present invention, and the device having immobilized thereon the molecule of the present invention are novel drugs and medical materials which can maintain the blood undifferentiated cells in the undifferentiated conditions. Antibodies against human Delta-1 and human Serrate-1 are prepared by using antigens of the said human Delta-1 and human Serrate-1, and purification method of the said antibodies are established. The present invention has been completed accordingly.
The present invention further related relates to a polypeptide comprising amino acid sequence of SEQ ID NO: 1 of the sequence listing encoded in a gene of human origin, a polypeptide comprising at least amino acid sequence of SEQ ID NO: 2 or NO: 5 of the sequence listing, the polypeptide comprising amino acid sequence of SEQ ID NO: 3 of the sequence listing, the polypeptide comprising amino acid sequence of SEQ ID NO: 4 of the sequence listing, the polypeptide comprising amino acid sequence of SEQ ID NO: 6 of the sequence listing, the polypeptide comprising amino acid sequence of SEQ ID NO: 7 of the sequence listing, the polypeptide having differentiation suppressive action against undifferentiated cells, the polypeptide in which undifferentiated cells are undifferentiated cells other than those of the brain and nervous system or muscular system cells, and the polypeptide in which undifferentiated cells are the undifferentiated blood cells. The present invention also relates to a pharmaceutical composition containing the polypeptides, and the pharmaceutical composition in which use there is as a hematopoietic activator. The present invention further relates to a cell culture medium containing the polypeptides, and the cell culture medium in which the cell is the undifferentiated blood cell. The present invention still further relates to a DNA coding a polypeptide at least having amino acid sequence of SEQ ID NO: 2 or NO: 5 of the sequence listing, the DNA having DNA sequence 242–841 of SEQ ID NO: 8 or DNA sequence 502–1095 of SEQ ID NO: 10 of the sequence listing, the DNA coding the polypeptide having amino acid sequence of SEQ ID NO: 3 of the sequence listing, the DNA coding the polypeptide having amino acid sequence of SEQ ID NO: 4 of the sequence listing, the DNA having DNA sequence 242–2347 of the SEQ ID NO: 8 of the sequence listing, the DNA coding the polypeptide having amino acid sequence of SEQ ID NO: 6 of the sequence listing, the DNA having DNA sequence 502–3609 of SEQ ID. NO: 10 of the sequence listing, the DNA coding the polypeptide having amino acid sequence of SEQ ID NO: 7 of the sequence listing, and the DNA having DNA sequence 502–4062 of SEQ ID NO: 10 of the sequence listing. The present invention still further relates to a recombinant DNA made by ligating a DNA selected from the groups of DNA hereinabove and a vector DNA which can express in the host cell, a cell transformed by the recombinant DNA, and a process for production of polypeptide by culturing cells and isolating the thus produced compound. The present invention still further relates to an antibody specifically recognizing the polypeptide having the amino acid sequence of SEQ ID NO: 7 of the sequence listing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is explained in details in the following:
Preparation of cDNA necessary for gene manipulation, expression analysis by Northern blotting, screening by hybridization, preparation of recombinant DNA, determination of DNA base sequence and preparation of cDNA library, all of which are series of molecular biological experiments, can be performed according to a description of the conventional textbook for the experiments. The above conventional textbook of the experiments is, for example, Maniatis et al. ed. Molecular Cloning, A laboratory manual, 1989, Eds., Sambrook, J., Fritsch, E. F. and Maniatis, T., Cold Spring Harbor Laboratory Press.
A polypeptide of the present invention has at least one of the polypeptides in the sequence listing SEQ ID NO: 1–7. A mutant and allele which naturally occur in the nature are included in the polypeptide of the present invention unless the polypeptides of the sequence listing, SEQ ID NO: 1–7 lose their properties. Modification and substitution of amino acids are described in details in the patent application by the name of Benntt et al. (National Unexam. Publ., WO96/2645) and can be prepared according to the description thereof.
A DNA sequence coding polypeptides of the sequence listing, SEQ ID NO: 2–4 is shown in the sequence listing, SEQ ID NO: 8, and a DNA sequence coding polypeptides of the sequence listing, SEQ ID NO: 5–7 is show in the sequence listing, SEQ ID NO: 10, together with their amino acid sequences. In these DNA sequences, even if amino acid level mutation is not generated, naturally isolated chromosomal DNA or cDNA thereof may have a possibility to mutate in the DNA base sequence as a result of degeneracy of genetic code without changing amino acid sequence coded by the DNA. A 5′-untranslated region and 3′-untranslated region are not involved in amino acid sequence determination of the polypeptide, so DNA sequences of these regions are easily mutated. The base sequence obtained by these degeneracies of genetic codes is included in the DNA of the present invention.
Undifferentiated cells in the present invention are defined as cells which can grow by specific stimulation, and cells which can be differentiated to the cells having specific functions as a result of the specific stimulations. These include undifferentiated cells of the skin tissues, undifferentiated cells of the brain and nervous systems, undifferentiated cells of the muscular systems and undifferentiated cells of the blood cells. These cells include the cells of self-replication activity which are called stem cells, and the cells having an ability to generate the cells of these lines. The differentiation-suppressive action means suppressive action for autonomous or heteronomous differentiation of the undifferentiated cells, and is an action for maintaining undifferentiated condition. The brain and nervous undifferentiated cells can be defined as cells having ability to differentiate to the cells of the brain or nerve having specific functions by specific stimulation. The undifferentiated cells of the muscular systems can be defined as cells having ability to differentiate to the muscular cells having specific functions by specific stimulation. The blood undifferentiated cells in the present invention can be defined as cell groups consisting of the blood precursor cells which are differentiated to the specific blood series identified by blood colony assay, and hematopoietic stem cells having differentiation to every series and self-replication activities.
In the sequence listing, amino acid sequence in SEQ ID NO: 1 shows general formula of common amino acid sequence of DSL domain which is a common domain structure of the Notch ligand molecules, and at least this domain structure corresponds to the sequence listing, AMINO ACIDS 158–200 of the human Delta-1, or the sequence listing AMINO ACIDS 156–198 of the human Serrate-1.
The amino acid sequence in the sequence listing, SEQ ID NO: 2 is a sequence of the active center of the present invention of human Delta-1 minus the signal peptide, i.e. amino acid sequence from the amino terminal to DSL domain, and corresponds to an amino acid No. 1 to 200 in SEQ ID NO: 4 of the mature full length amino acid sequence of human Delta-1 of the present invention. The amino acid sequence in SEQ ID NO: 3 is amino acid sequence of extracellular domain of the present invention of human Delta-1 minus the signal peptide, and corresponds to an amino acid No. 1 to 520 in SEQ ID NO: 4 of the mature full length amino acid sequence of human Delta-1 of the present invention. The amino acid sequence of SEQ ID NO: 4 is the mature frill length amino acid sequence of the human Delta-1 of the present invention.
The amino acid sequence in the sequence listing, SEQ ID NO: 5 is a sequence of the active center of the present invention of human Serrate-1 minus the signal peptide, i.e. amino acid sequence from the amino terminal to DSL domain, and corresponds to an amino acid No. 1 to 198 in SEQ ID NO: 7 of the mature full length amino acid sequence of human Serrate-1 of the present invention. The amino acid sequence in SEQ ID NO: 6 is amino acid sequence of extracellular domain of the present invention of human Serrate-1 minus the signal peptide, and corresponds to an amino acid No. 1 to 1036 in SEQ ID NO: 7 of the mature full length amino acid sequence of human Serrate-1 of the present invention. The amino acid sequence of SEQ ID NO: 7 is the mature full length amino acid sequence of the human Serrate-1 of the present invention.
The sequence of SEQ ID NO: 8 is the total amino acid sequence of human Delta-1 of the present invention and cDNA coding the same, and the sequence of SEQ ID NO: 10 is total amino acid sequence of human Serrate-1 of the present invention and cDNA coding the same.
The left and right ends of the amino acid sequences in the sequence listing indicate amino terminal (hereinafter designated as N-terminal) and carboxyl terminal (hereinafter designated as C-terminal), respectively, and the left and right ends of the nucleotide sequences are 5′-terminal and 3′-terminal, respectively.
Cloning of human Notch ligand gene can be performed by the following method. During the evolution of the organisms, a part of amino acids sequences of the human Notch ligand is conserved. DNA sequence corresponding to the conserved amino acid sequence is designed, and is used as a primer of RT-PCR (Reverse Transcription Polymerase Chain reaction), then a PCR template of the human origin is amplified by PCR reaction, thereby fragments of human Notch ligand can be obtainable. Furthermore, RT-PCR primer is prepared by applying the known DNA sequence information of the Notch ligand homologue of the organisms other than humans, and the known gene fragments can be possibly obtained from PCR template of the said organisms.
In order to perform PCR for obtaining fragments of human Notch ligand, PCR for DSL sequence is considered, but a large number of combinations of DNA sequence corresponding to amino acid sequence conserved in this region can be expected, and a design for PCR is difficult. As a result, PCR of the EGF-like sequence has to be selected. As explained hereinbefore, since EFG-like sequence is conserved in a large number of molecules, to obtain the fragments and identification are extremely difficult.
We have designed and prepared about 50 PCR primer sets, for example, the primer set of the sequence shown in Example 1, PCR was performed with these primer sets by using PCR template of cDNA prepared from poly A+ RNA of various tissues of human origin, and more than 10 PCR products from each tissue were subcloned, as well as performing sequencing for more than 500 types. A clone having a desired sequence could be identified. Namely, the obtained PCR product is cloned in the cloning vector, transforming the host cells by using recombinant plasmid which contains the PCR product, culturing the host cells containing the recombinant plasmid on a large scale, purifying and isolating the recombinant plasmid, checking the DNA sequence of PCR product which is inserted into the cloning vector, and trying to obtain the gene fragment which may have a sequence of human Delta-1 by comparing with the sequence of the known Delta of other species. We have succeeded to find out the gene fragment which contains a part of cDNA of human Delta-1, the same sequence of DNA sequence from 1012 to 1375 described in the sequence listing, SEQ ID NO: 8.
We have also designed and prepared about 50 PCR primer sets, for example, the primer set of the sequence shown in Example 3, and PCR was performed with these primer sets by using PCR template of cDNA prepared from poly A+ RNA of various tissues of human origin, and more than 10 PCR products from each tissue were subcloned, as well as performing sequencing for more that 500 types. A clone having a desired sequence could be identified. Namely, the obtained PCR product is cloned in the cloning vector, transforming the host cells by using recombinant plasmid which contains the PCR product, culturing the host cells containing the recombinant plasmid on a large scale, purifying and isolating the recombinant plasmic, checking the DNA sequence of PCR product which is inserted into the cloning vector, and trying to obtain the gene fragment which may have a sequence of human Serrate-1 by comparing with the sequence of the known Serrate of other species. We have succeeded to find out the gene fragment which contains a part of cDNA of human Serrate-1, the same sequence of DNA sequence from 1272 to 1737 described in the sequence listing, SEQ ID NO: 10.
A full length of the objective gene can be obtained form the human genomic gene library or cDNA library by using the thus obtained human Delta-1 fragment or human Serrate-1 gene fragment. The full length cloning can be made by isotope labeling and non-isotope labeling with the partial cloning gene, and screening the library by hybridization or other method. Isotope labeling can be performed by, for example, terminal labeling by using [ 32 P] γ-ATP and T4 polynucleotide kinase, or other labeling methods such as nick translation or primer extension method can be applied. In another method, human originated cDNA library is ligated into the expression vector, expressing by COS-7 or other cells, and screening the objective gene by expression cloning to isolate cDNA of the ligand. In the expression cloning, a cell sorter fractionation method which is applied with binding with polypeptide containing amino acid sequence of prior known 4 Notches such as TAN-1, and a detection method by film emulsion using radioisotope can be mentioned. In this specification, methods for obtaining genes of human Delta-1 and human Serrate-1 are explained, and in addition to that obtaining the Notch ligand homologue gene of the other organism is important for analysis of ligand action. This may be made by the same treatment. The obtained gene is subjected to DNA sequence determination and amino acid sequence can be estimated.
As shown in Example 2, gene fragments containing human Delta-1 PCR product are labeled with radioisotope to prepare hybridization probe screening is performed using cDNA of human placenta origin as the screening library. DNA sequences of the thus obtained clones are determined, and the clone is obtained containing DNA nucleotide sequence shown in the sequence listing. SEQ ID NO: 8, and shown to have the amino acid sequence coded in the sequence listing. SEQ ID NO: 4. We have succeeded in cloning cDNA coding full length of amino acids sequence of human Delta-1.
These sequences were compared with the data base (Genbank release 89, June, 1995), and found that these were novel sequences. The said amino acid sequence was analyzed in hydrophilic part and hydrophobic part according to a method by Kyte-Doolittle (J. Mol. Biol. 157: 105, 1982). A result indicated that human Delta-1 of the present invention is expressed on cells as a cellular membrane protein having a transmembrane domain.
As shown in Example 4, gene fragments containing human Serrate-1 PCR product are labeled with radioisotope to prepare hybridization probe, screening is performed using cDNA of human placenta origin as the screening library, DNA sequences of the thus obtained clones are determined and the clone is obtained containing DNA nucleotide sequence shown in the sequence listing, SEQ ID NO: 10, and shown to have the amino acid sequence coded in the sequence listing, SEQ ID NO: 7. In this screening, an intracellular part of gene sequence coding a full length of amino acids sequence, namely a peripheral part of termination codon cannot be cloned. Consequently, as shown in Example 4, gene cloning is performed by RACE method (rapid amplification of cDNA ends, Frohman et al., Proc. Natl. Acad. Sci. U.S.A. 85, 8998–9002, 1988) and finally succeeded in cloning of cDNA coding full length of amino acid sequence of human Serrate-1.
These sequences were compared with the data base (Genbank release 89, June, 1995, and found that these were novel sequences. The said amino acid sequence was analyzed in hydrophilic part and hydrophobic part according to a method by Kyte-Doolittle (J. Mol. Biol. 157: 105, 1982). A result indicated that human Serrate-1 of the present invention is expressed on cells as a cellular membrane protein having a transmembrane domain.
Examples of plasmids integrated with cDNA are, for example, E. coli originated pBR322, pUC18, pUC19, pUC118 and pUC119 (Talkara Shuzo Co., Japan), but other plasmids can be used if they can replicate and proliferate in the host cells. Examples of phage vectors integrated with cDNA are, for example, λgt10 and λgt11, but other vectors can be used if they can grow in the host cells. The thus obtained plasmids are transducted into suitable host cells such as genus Escherichia and genus Bacillus using calcium chloride method. Examples of the above genus Escherichia are Escherichia coli K12HB101, MC1061, LE392 and HM109. Example of the above genus Bacillus is Bacillus subtilis MI114. Phage vector can be introduced into the proliferated E. coli by the in vitro packaging method (Enquist and Sternberg, Meth. Enzymol., 68, 281-, 1979).
According to the analysis of amino acid sequence of the human Delta-1, amino acid sequence of a precursor of human Delta-1 consists of 723 amino acids residue shown in the sequence listing, SEQ ID NO: 8, and the signal peptide domain is estimated to correspond to an amino acid sequence of 21 amino acids residue from No. −21 methionine to No. −1 serine of the sequence listing; extracellular domain: 520 amino acids residue from No. 521 proline to No. 552 leucine; and intracellular domain: 150 amino acids region from No. 553 glutamine to No. 702 valine. These domains are estimated domain construction from amino acid sequences, and actual presence form may differ from the above structure, and constitutional amino acids of each domain hereinabove defined may have possibility to change 5 to 10 amino acids sequence.
According to a comparison in amino acid sequence of human Delta-1 and Delta homologue of the other organisms, the homologies with Drosophila Delta, chick Delta and Xenopus laevis are 47.6%, 83.3% and 76.2%, respectively. The human Delta-1 of the present invention is different from these Deltas and is novel substance which is clarified at first by the present inventors. Search from all of organisms in the above data base indicated that polypeptides having the identical sequence of the human Delta-1 could not be found.
The homologues of Notch ligand have evolutinally conserved common sequence, i.e. repeated DSL sequence and EGF-like sequence. As a result of comparison with amino acid sequence of human Delta-1, these conserved sequence is estimated. Namely, DSL sequence corresponds to 43 amino acids residue from No. 158 cysteine to No. 200 cysteine of the amino acid sequence in the sequence listing, SEQ ID NO: 4. EGF-like sequence exists with 8 repeats wherein, in the amino acid sequence in the sequence listing SEQ ID NO: 4, the first EGF-like sequence from No. 205 cysteine to No. 233 cysteine; the second EGF-like sequence from No. 236 cysteine to No. 264 cysteine; the third EGF-like sequence from No. 271 cysteine to No. 304 cysteine; the fourth EGF-like sequence from No. 311 cysteine to No. 342 cysteine; the fifth EGF-like sequence from No. 349 cysteine to No. 381 cysteine; the sixth EGF-like sequence from No. 388 cysteine to No. 419 cysteine; the seventh EGF-like sequence from No. 426 cysteine to No. 457 cysteine; and the eighth EGF-like sequence from No. 464 cysteine to No. 495 cysteine.
A part of sugar chain attached is estimated from amino acid sequence of the human Delta-1 may be No. 456 asparagine residue in the sequence listing, SEQ ID NO: 4 as a possible binding site of N-glycoside bonding for N-acetyl-D-glucosamine. O-glycoside bond of N-acetyl-D-galactosamine is estimated to be a serine or threonine residue rich part. Protein bound with sugar chain is generally thought to be stable in vivo and to have strong physiological activity. Consequently, in the amino acid sequence of polypeptide having sequence of the sequence listing, SEQ ID NO: 2, 3 or 4, polypeptides having N-glucoside or O-glucoside bond with sugar chain of N-acetyl-D-glucosamine or N-acetyl-D-galactosamine is included in the present invention.
According to the analysis of amino acid sequence of the human Serrate-1, amino acid sequence of a precursor of human Serrate-1 consists of 1218 amino acids residue shown in the sequence listing, SEQ ID NO: 10, and the signal peptide domain is estimated to correspond 31 amino acids residue in the amino acid sequence from No. −31 methionine to No. −1 alanine of the sequence listing; extracellular domain: 10366 amino acids residue from No. 1 serine to No. 1036 asparagine; transmembrane domain: 26 amino acids residue from No. 1037 phenylalanine to No. 1062 leucine; and intracellular domain: 106 amino acids domain from No. 1063 arginine to No. 1187 valine. These domains are estimated domain construction from amino acid sequences, and actual presence form may differ from the above structure, and constitutional amino acids of each domain hereinabove defined may have possibility to change 5 to 10 amino acids sequence.
According to a comparison in amino acid sequence of human serrate-1 and Serrate homologue of the other organisms, the homologies with Drosophila Serrate, and rat Jagged are 32.1% and 95.30%, respectively. The human Serrate-1 of the present invention is different from these Serrates and is novel substance which is clarified at first by the present inventors. Search from all of organisms in the above data base indicated that polypeptides having the identical sequence of the human Serrate-1 could not find out.
The homologues of Notch ligand have evolutionally conserved common sequence, i.e. repeated DSL sequence and EGF-like sequence. As a result of comparison with amino acid sequence of human Serrate-1 and other Notch ligand homologues, these conserved sequence is estimated. Namely, DSL sequence corresponds to 43 amino acids residue from No. 156 cysteine to No. 198 cysteine of the amino acid sequence in the sequence listing, SEQ ID NO: 7. EGF-like sequence exists with 16 repeats wherein, in the amino acid sequence in the sequence listing, SEQ ID NO: 7, the first EGF-like sequence from No. 205 cysteine to No. 231 cysteine; the second EGF-like sequence from No. 234 cysteine to No. 262 cysteine; the third EGF-like sequence from No. 269 cysteine to No. 302 cysteine; the fourth EGF-like sequence from No. 309 cysteine to No. 340 cysteine; the fifth EGF-like sequence from No. 356 cysteine to No. 378 cysteine; the sixth EGF-like sequence from No. 423 cysteine to No. 453 cysteine; the eighth EGF-like sequence from No. 462 cysteine to No. 453 cysteine; the nineth EGF-like sequence from No. 498 cysteine to No. 529 cysteine; the 10 th EGF-like sequence from No. 536 cysteine to No. 595 cysteine; the 11th EGF-like sequence from No. 602 cysteine to No. 633 cysteine; the 12 th EGF-like sequence from No. 640 cysteine to No. 671 cysteine; the 13 th EGF-like sequence from No. 678 cysteine to No. 709 cysteine; the 14 th EGF-like sequence from No. 717 cysteine to No. 748 cysteine; and the 16 th EGF-like sequence from No. 793 cysteine to No. 824 cysteine. However, the 10 th EGF-like sequence has irregular sequence containing 10 residues of cysteine.
A part of sugar chain attached is estimated from amino acid Sequence of the human Serrate-1 may be No. 112, 131, 186, 351, 528, 554, 714, 1014 and 1033 asparagine residue in the sequence listing. SEQ ID NO: 7 as a possible binding site of N-glycoside bonding for N-acetyl-D-glycosamine. O-glycoside bond of N-acetyl-D-galactosamine is estimated to be a serine or threonine residue rich part, Protein bound with sugar chain is generally thought to be stable in vivo and to have strong physiological activity. Consequently, in the amino acid sequence of polypeptide having sequence of the sequence listing, SEQ ID NO: 5, 6 or 7, polypeptides having N-glucoside or O-glucoside bond with sugar chain of N-acetyl-D-glucosamine or N-acetyl-D-galactosamine is included in the present invention.
As a result of studies on binding of Drosophila Notch and its ligand, amino acid region necessary for binding with ligand of Drosophila Notch with the Notch is from N-terminal to DSL sequence of the matured protein, in which signal peptide is removed (Japan. Pat. PCT Unexam. Publ. No. 7-503121). This fact indicates that a domain necessary for expression of ligand action of human Notch ligand molecule is at least the DSL domain. i.e. a domain containing amino acid sequence of the sequence listing, SEQ ID NO: 1, and a domain at least necessary for expression of ligand action of human Delta-1 is novel amino acid sequence shown in the sequence listing, SEQ ID NO: 2, and further a domain at least necessary for expression of ligand action of human Serrate-1 is novel amino acid sequence shown in the sequence listing. SEQ ID NO: 5.
An mRNA of human Delta-1 can be detected by using DNA coding a part or all of gene sequence in the sequence listing, SEQ ID NO: 8, and an mRNA of human Serrate-1 can be detected by using DNA coding a part or all of gene sequence in the sequence listing, SEQ ID NO: 10. For example, a method for detection of expression of these genes can be achieved by applying with hybridization or PCR by using complementary nucleic acids of above 12 mer or above 16 mer, preferably above 18 mer having nucleic acid sequence of a part of sequence in the sequence listing, SEQ ID NO: 8 or 10, i.e. antisense DNA or antisense RNA, its methylated, methylphosphated, deaminated, or thiophosphated derivatives. By the same method, detection of homologues of the gene of other organisms such as mice or gene cloning can be achieved. Further cloning of genes in the genome including humans can be made. Using these genes cloned by such like methods, further detailed functions of the human Delta-1 or human Serrate-1 of the present invention can be clarified. For example, using the modern gene manipuration techniques, every methods including transgenic mouse, gene targeting mouse or double knockout mouse in which genes relating to the gene of the present invention are inactivated, can be applied. If abnomalities in the genome of the present gene is found, application to gene diagnosis and gene therapy can be made.
A transformant in which vector pUCDL-1F, which contains cDNA coding total animo acid sequence of human Delta-1 of the present invention, is transformed into E. coli JM109, has been deposited in the National Institute of Bioscience and Human-Technology, Agency of industrial Science and Technology, MITI, of 1-1-3, Higasi, Tsukuba-shi, Ibaragi-ken, Japan, as E. coli : JM109-pUCDL-1F. Date of deposit was Oct. 28, 1996, and deposition No. is FBRM BP-5728. A transformant in which vector pUCSR-1, which contains cDNA coding total animo acid sequence of human Serrate-1 of the present invention, is transformed into E. coli JM109, has been deposited in the National Institute of Bioscience and Human-Technology, Agency of Industrial Science and Technology, MITI, of 1-1-3. Higasi, Tsukuba-shi, Ibaragi-ken, Japan, as E. coli : JM109-pUCSR-1. Date of deposit was Oct. 28, 1996, and deposition No. is FBRM BP-5726.
Expression and purification of various forms of human Delta-1 and human Serrate-1 using cDNA coding amino acid sequence of human Delta-1 and human Serrate-1 isolated by the above methods are known in the references (Kriegler, Gene Transfer and Expression—A Laboratory Manual Stockton Press, 1990 and Yokota et al. Biomanual Series 4, Gene transfer and expression and analysis, Yodosha Co., 1994). A cDNA coding the amino acid sequence of the isolated said human Delta-1 and human Serrate-1 is ligated to preferable expression vector and is produced in the host cells of eukaryotic cells such as animal cells and insect cells or prokaryotic cells such as bacteria.
In the expression of human Delta-1 and human Serrate-1 of the present invention, DNA coding polypeptide of the present invention may have the translation initiation codon in 5′-terminal and translation termination codon in 3′-terminal. These translation initiation codon and translation termination codon can be added by using preferable synthetic DNA adapter. Further for expression of the said DNA, promoter is linkaged in the upstream of the DNA sequence. Examples of vector are plasmid originated from Bacillus , plasmid originated from yeast or bacteriophage such as λ-phage and animal virus such as retrovirus and vaccinia virus.
Examples of promoters used in the present invention are any promoters preferable for corresponding to the host cells used in gene expression.
In case that the host cell in the transformation is genus Escherichia , tac-promoter, trp-promoter and lac-promoter are preferable, and in case of host of genus Bacillus , SPO1 promoter and SP02 promoter are preferable, and in case of host of yeast, PGK promoter, GAP promoter and ADH promoter are preferable.
In case that the host cell is animal cells, a promoter originated from SV40 such as SRα promoter as described in Example 51 promoter of retrovirus, metallothionein promoter and heatshock promoter can be applied.
Polypeptide of the present invention can be expressed by using the expression vector having ability to be used by any person skilled in the arts.
Expression of the polypeptide of the present invention can be made by using only DNA coding the amino acid sequence of the sequence listing, SEQ ID NO: 2, 3, 4, 5, 6 or 7. However, the protein added with specific function can be produced by using DNA, to which added cDNA coding the known antigen epitope for easier detection of the produced polypeptide or added cDNA coding the immunoglobulin Fc for forming multimer.
As shown in Example 5, we have prepared expression vectors, which express extracellular proteins of human Delta-1, as follows:
1) DNA coding the amino acids from No. 1 to 520 in amino acid sequence in the sequence listing, SEQ ID NO: 3, 2) DNA coding chimera protein to which added polypeptide having 8 amino acid, i.e. an amino acid sequence consisting of Asp Tyr Lys Asp Asp Asp Asp Lys (hereinafter, designates FLAG sequence, the sequence listing. SEQ ID NO: 12), in the C-terminal of the amino acids from No. 1 to 520 in amino acid sequence in the sequence listing, SEQ ID NO: 3, and 3) DNA coding chimera protein to which added Fc sequence below the hinge region of human IgG1 (refer to International Patent Publ. WO96/11221 in the C-terminal of the amino acids from No. 1 to 520 in amino acid sequence in the sequence listing. SEQ ID NO:3, and to have dimer structure by disulfide bond in the hinge region,
are ligated individually with the expression vector pMKITNeo (Maruyama et al. Japan Molecular Biology Soc. Meeting Preliminary lecture record, obtainable from Dr. Maruyama in Tokyo Medical and Dental College, containing promoter SRα) to prepare extracellular expression vectors of human Delta-1.
The full-length expression vectors of the human Delta-1 as the expression vectors, which express full-length proteins of the human Delta-1, can be prepared as follows.
4) DNA coding amino acids from No. 1 to 702 in the sequence listing. SEQ ID NO: 4 and 5) DNA coding chimera protein to which added polypeptide having FLAG sequence in the C-terminal of amino acids from No. 1 to 702 in the sequence listing, SEQ ID NO: 4
are ligated individually with the expression vector pMIKITNeo to prepare the full-length expression vectors of human Delta-1. The transformant is prepared by using expression plasmid containing DNA coding the thus constructed said human Delta-1.
As shown in Example 6, we have prepared expression vectors, which express extracellular proteins of human Serrate-1, as follows.
6) DNA coding the amino acids from No. 1 to 1036 in amino acid sequence in the sequence listing, SEQ ID NO: 6, 7) DNA coding chimera protein to which added polypeptide having FLAG sequence in the C-terminal of the amino acids from No. 1 to 1036 in amino acid sequence in the sequence listing, SEQ ID NO: 6, and 8) DNA coding chimera protein to which added said Fc sequence in the C-terminal of the amino acids from No. 1 to 1036 in amino acid sequence in the sequence listing, SEQ ID NO: 6, and to have dimer structure by disulfide bond in the hinge region,
are ligated individually with the expression vector pMKITNeo to prepare extracellular expression vectors of human Serrate-1.
The full-length expression vectors of the human Serrate-1 as the expression vectors, which express full-length proteins of the human Serrate-1, can be prepared as follows.
9) DNA coding amino acids from No. 1 to 1187 in the sequence listing, SEQ ID NO: 7 and 10) DNA coding chimera protein to which added polypeptide having FLAG sequence in the C-terminal of amino acids from No. 1 to 1187 in the sequence listing, SEQ ID NO: 7
are ligated individually with the expression vector pMKITNeo to prepare the full-length expression vectors of human Serrate-1. The transformant is prepared by using expression plasmid containing DNA coding the thus constructed said human Serrate-1.
Examples of the host are genus Escherichia , genus Bacillus , yeast and animal cells. Examples of animal cells are simian cell COS-7 and Vero, Chinese hamster cell CHO and silk worm cell SF9.
As shown in Example 7, the above expression vectors 1)–10) are transduced individually; the human Delta-1 or human Serrate-1 are expressed in COS-7 cell (obtainable from the Institute of Physical and Chemical Research, Cell Development Bank, RCB0539), and the transformants which were transformed by these expression plasmids, can be obtained. Further, human Delta-1 polypeptide and human Serrate-1 polypeptide can be produced by culturing the transformants under preferable culture condition in medium by known culture method.
As shown in Example 8, human Delta-1 polypeptide and human Serrate-1 polypeptide can be isolated and purified from the above cultured mass, in general, by the following methods.
For extraction of the substance from cultured microbial cells or cells, microbial cells or cells are collected by known method such as centrifugation after the cultivation, suspended in preferable buffer solution, disrupted the microbial cells or cells by means of ultrasonication, lysozyme and/or freeze-thawing and collected crude extract by centrifugation or filtration. The buffer solution may contain protein-denaturing agents such as urea and guanidine hydrochloride or surface active agents such as Triton-X. In case of secretion in the cultured solution, the cultured mass is separated by the known method such as centrifugation to separate from microbial cells or cells and the supernatant solution is collected.
The thus obtained human Delta-1 or human Serrate-1, which are contained in the cell extracts or cell supernatants, can be purified by known protein purification methods. During the purification process, for confirmation of existence of the protein, in case of the fused proteins of the above FLAG and human IgGFc, they can be detected by immunoassay using antibody against known antigen epitope and can be purified. In case of not to express as such the fused protein, the antibody in Example 9 can be used for detection.
Antibodies, which specifically recognize human Delta-1 and human Serrate-1, can be prepared as shown in Example 9. Antibodies can be prepared by the methods described in the reference (Antibodies a laboratory manual, E. Harlow et al., Cold Spring Harbor Laboratory) or recombinant antibodies expressed in cells by using immunoglobulin genes isolated by gene cloning method. The thus prepared antibodies can be used for purification of human Delta-1 and human Serrate-1. The human Delta-1 or human Serrate-1 can be detected and assayed by using antibodies which recognize specifically human Delta-1 or human Serrate-1 as shown in Example 9, and can be used for diagnostic agents for diseases accompanied with abnormal differentiation of cells such as malignant tumors.
More useful purification method is the affinity chromatography using antibody. Antibodies used in this case are antibodies described in Example 9. For fused protein, antibodies against FLAG in the case of FLAG, and protein G or protein A in the case of human IgGFc as shown in Example 8.
Any fused protein other than the protein as shown hereinabove can be used. For example, histidine Tag and myc-tag can be mentioned. Any fused proteins can be prepared by using methods of present day genetic engineering techniques other than the known methods, and peptides of the present invention derived from those fused proteins are in the scope of the present invention.
Physiological functions of the thus purified human Delta-1 and human Serrate-1 proteins can be identified by various assay methods, for example, physiological activity assaying methods using cell lines and animals such as mice and rats, assay methods of intracellular signal transduction based on molecular biological means, binding with Notch receptor etc.
We have observed actions for blood undifferentiated cells by using IgG1 chimera proteins of human Delta-1 and human Serrate-1.
As a result, we have found that, as shown in Example 10, in the umbilical cord blood derived blood undifferentiated cells, in which CD34 positive cell fraction is concentrated, polypeptides of the present invention have suppressive action of colony forming action against blood undifferentiated cells, which shows colony formation in the presence of cytokines. The suppressive action is only observed in the presence of SCF. This kind of effect has never been known.
As shown in Example 11, we have found that a maintenance of colony forming cells is significantly extended by addition of IgG1 chimera protein of human Delta-1 or human Serrate-1 in the long term (8 weeks) liquid culture in the presence of cytokines such as SCF. IL-3, IL-6. GM-CSF and Epo. Further we have found that the polypeptides of the present invention had an action not to suppress growth of the colony forming cells. A cytokine, MIP-1α having migration and differentiation suppressive action of blood cells (Verfaillie et al., J. Exp. Med. 179, 643–649, 1994), has no action for maintaining undifferentiation for blood undifferentiated cells.
Further as shown in Example 12, we have found that as a result of adding IgG1 chimera protein of human Delta-1 or human Serrate-1 to the liquid culture in the presence of cytokines, the human Delta-1 and human Serrate-1 had activities for significantly maintaining LTC-IC (Long-Term Culture-Initiating Cells) number, which is positioned most undifferentiated blood stem cells in the human blood undifferentiated cells.
These results indicate that the human Delta-1 and human Serrate-1 suppress differentiation of blood undifferentiated cells, and these actions spread from blood stem cells to colony forming cells. These physiological actions are essential for in vitro expansion of blood undifferentiated cells. Cells cultured in the medium containing human Delta-1 or human Serrate-1 are efficient in recovery of suppresion of bone marrow after administration of antitumor agents, accordingly in vitro growth of hemopoietic stem cells may be possible if other conditions would be completed. Further pharmaceuticals containing the polypeptide of the present invention have action protection and release of the bone marrow suppressive action, which is observed in adverse effects of antitumor agents.
Suppressive action for differentiation of cells in the undifferentiated cells other than blood cells is expected and stimulating action for tissue regeneration can be expected.
In the pharmaceutical use, polypeptides of the present invention are lyophilized with adding preferable stabilizing agents such as human serum albumin, and is used in dissolved or suspended condition with distilled water for injection when it is in use. For example, preparation for injection or infusion at the concentration of 0.1–1000 μg/ml may be provided. A mixture of the compound of the present invention 1 mg/ml and human serum albumin 1 mg/ml divided in a vial could maintain activity of the said compound for long term. For culturing and activating cells in vitro, lyophilized preparation or liquid preparation of the polypeptide of the present invention are prepared and are added to the medium or immobilized in the vessel for culture. Toxicity of the polypeptide of the present invention was tested. Any polypeptide, 10 mg/kg was administered intraperitoneally in mice, but no death of mice was observed.
In vitro physiological activity of the polypeptide of the present invention can be evaluated by administering to disease model mice or its resembled disease-rats or monkeys, and examining recovery of physical and physiological functions and abnormal findings. For example, in case of searching abnormality in relation to hemopoietic cells, bone marrow suppressive model mice are prepared by administering 5-FU series of antitumor agents, and bone marrow cell counts, peripheral blood cell counts and physiological functions are examined in the administered group or the non administered group of mice. Further, in case of searching in vitro cultivation and growth of hemopoietic undifferentiated cells including hemopoietic stem cells, the bone marrow cells of mice are cultured in the groups with or without addition of the compound of the present invention, and the cultured cells are transferred into the lethal dose irradiated mice. Result of recovery is observed with the indications of survival rate and variation of blood counts. These results can be extrapolated to the humans, and accordingly useful effective data for evaluation of the pharmacological activities of the compound of the present invention can be obtained.
Applications of the compound of the present invention for pharmaceuticals include diseases with abnormal differentiation of cells, for example leukemia and malignant tumors. These are cell therapy, which is performed by culturing human derived cells in vitro while maintaining their original functions or adding new functions, and a therapy, which is performed by regenerating without damaging the functions originally existing in the tissues by administering the compound of the present invention under the regeneration after tissue injury. Amount of administration may differ in the type of preparation and ranges from 10 μg/kg to 10 mg/kg.
Further strong physiological activity can be achieved by expression of forming multimer of the polypeptide of the present invention.
As shown in Example 10, since the suppressive action of human Delta-1 and human Serrate-1 is stronger in the IgG chimera protein having dimer structure, a form of stronger physiological activity is preferably expressed in the form of multimer formation.
Human Delta-1 and human Serrate-1 having multimer structure can be produced by a method of expressing chimera protein with human IgG Fc region as described in the example and expressing the multimer having disulfide bond with hinge region of the antibody, or a method expressing chimera protein, in which antibody recognition region is expressed in the C-terminal or N-terminal, and reacting with the polypeptide containing extracellular part of the thus said Delta-1 and Human Serrate-1 and/the antibody which recognize specifically the antibody recognition region in the C-terminal or N-terminal. In the other methods, a method, in which a fused protein expressed with only the hinge region of the antibody and the dimerized by disulfide bond, can be mentioned. The multimer of human Delta-1 and human Serrate-1 having higher specific activity than the dimer can be obtained. The said multimer is constructed by fused protein which is prepared for expressing the peptide in the C-terminal, N-terminal or other region. The protein is prepared in the form of forming disulfide bond without effecting in any activities of the other human Delta-1 or human Serrate-1. The multimer structure can also be expressed by arranging one or more peptide, which is selected from polypeptides containing amino acids sequence of the sequence listing, SEQ ID NO: 2, 3, 5 or 6, with genetic engineering method in series or in parallel. Other known methods for providing multimer structure having dimer or higher can be applied. Accordingly, the present invention includes any polypeptides containing amino acid sequences described in the sequence listing, SEQ ID NO: 2, 3, 5 or 6 in the form of dimer or higher more structure prepared by genetic engineering technique.
Further in the other method, multimerization method using chemical cross-linker can be mentioned. For example, dimethylsuberimidate dihydrochloride for cross-linking lysine residue, N-(γ-maleimidebutyryloxy) succinimide for cross-linking thiol group of cysteine residue and glutaraldehyde for cross-linking between amino groups can be mentioned. The multimer with dimer or more can be synthesized by applying these cross-linking reactions. Accordingly, the present invention includes any polypeptides containing amino acid sequences described in the sequence listing. SEQ ID NO: 2, 3, 5 or 6 in the form of dimer or more structure prepared by chemical cross-linking agents.
In application of medical care in which cells are proliferated and activated in vitro and are returned to the body, human Delta-1 or human Serrate-1 of the form hereinabove can be added directly in the medium, but immobilization can also be made. Immobilization method includes applying amino group or carboxyl group in the peptide using suitable spacers or the above mentioned cross-linkers, and the polypeptide can be covalently bound to the culture vessels. Accordingly, the present invention includes any polypeptides containing amino acid sequences described in the sequence listing, SEQ ID NO: 2, 3, 5 or 6 in the form of existing on the solid surface.
Since the natural human Delta-1 and human Serrate-1 are cell membrane proteins, differentiation suppressive action in the Examples can be expressed by cocultivating with cells expressing these molecules and blood undifferentiated cells. Consequently, this invention includes cocultivation method with transformed cells by using DNA coding amino acid sequences in the sequence listing, SEQ ID NO: 2–7 and undifferentiated cells.
Expressed cell may be COS-7 cell as shown in Examples, but cells of human origin are preferable, and further expressed cells may be cell line or any of human in vivo blood cells and somatic cells. Consequently, the polypeptide can be expressed in vivo by integrated into vectors for gene therapy.
As shown in Example 10, FLAG chimera protein of human Delta-1 or human Serrate-1, both of which are low concentrated monomer, shows not a colony formation suppressive action but a colony formation stimulating action. This action may be involved in expressing Notch receptor and Notch ligand in the occasion of cell division of blood undifferentiated cells and acting the polypeptide of the present invention as an antagonist for that action. This suggests that the polypeptide having amino acid sequence of the sequence listing, SEQ ID NO: 1, 2, 4 or 5, shows colony formation stimulation action by controlling the concentration of its action.
This fact suggests that inhibition of binding the polypeptide having amino acid sequence in the sequence listing, SEQ ID NO: 2–7 and these receptors can be used for finding out molecules and compounds for stimulating cell differentiation. The methods include binding experiment using radio isotope, luciferase assay using transcriptional control factors, a down stream molecule of the Notch receptor, and simulation on the computer by X-ray structural analysis. Accordingly, the present invention includes screening method for pharmaceuticals using polypeptide in the sequence listing, SEQ ID NO: 2–7.
As shown in Example 13, specific leukemia cells can be differentiated by using IgG chimera protein of human Delta-1 or human Serrate-1. Consequently, the present invention can be applied for diagnostic reagents for leukemia or isolation of specific blood cells. This result indicates that human Delta-1 or human Serrate-1 molecule binds specifically with its receptor, a Notch receptor molecule. For example, expression of Notch receptor can be detected by using fused protein with the above extracellular region and human IgGFc. Notch is known to involve in some type of leukemia (Ellisen et al., Cell 66, 649–661, 1991). Accordingly, the polypeptide having amino acids sequence in the sequence listing. SEQ ID NO: 2, 3, 5 and 6 can be used for diagnostic reagents for in vitro or in vivo.
BRIEF EXPLANATION OF THE DRAWINGS
FIG. 1 : Alignment of DSL domain of Notch ligand identified in various organisms including the molecules of the present invention, wherein the consensus sequence is SEQ ID NO: 40, hDelta-1.DSL is SEQ ID NO: 41, dDelta.DSL is SEQ ID NO: 42, xDelta.DSL is SEQ ID NO: 43, cDelta-1.DSL is SEQ ID NO: 44, mDelta-1.DSL is SEQ ID NO: 45, hSerrate-1.DSL is SEQ ID NO: 46, dSerrate.DSL is SEQ ID NO: 47, and rJagged.DSL is SEQ ID NO: 48.
FIGS. 2A and 2B : Suppression of colony formation of the blood undifferentiated cells using the molecules of the present invention.
FIG. 3 : Concentration dependency of colony formation suppression of the blood undifferentiated cells using the molecules of the present invention.
FIG. 4 : A graph showing calculation of LTC-1 after liquid culture using the molecules of the present invention.
FIGS. 5A and 5B : Cells stained by the molecules of the present invention.
EXAMPLES
Following examples illustrate the embodiments of the present invention but are not construed as limiting these examples.
Example 1
Cloning of PCR Products Using Human Delta-1 Primer and Determination of Base Sequence
A mixed primer corresponding to amino acid sequence conserved in C-Delta-1 and X-Delta-1, i.e. sense primer DLTS1 (sequence listing, SEQ ID NO: 14) and antisense primer DLTA2 (sequence listing, SEQ ID NO: 15), were used.
A synthetic oligonucleotide was prepared by using automatic DNA synthesizer with the principle of immobilized method. The automatic DNA synthesizer used was 391PCR-MATE of Applied Biosystems Inc., U.S.A. Nucleotide, carrier immobilized with 3′-nucleotide, solution and reagents are used according to the instructions by the same corporation. Oligonucleotide was isolated from the carrier after finishing the designated coupling reaction and treating the oligonucleotide carrier from which protective group of 5′-terminal was removed, with concentrated liquid ammonia at room temperature for one hour. For removing the protective groups of nucleic acid and phosphoric acid, the reactant solution containing nucleic acid was allowed to stand in the concentrated ammonium solution in the sealed vial at 55° C. for over 14 hours. Each oligonucleotide, from which the carrier and protective groups were removed, was purified by using OPC cartridge of the Applied Biosystems Inc., and detritylated by using 2% trifluoracetic acid. Primer was dissolved in deionized water to set final concentration of 100 pmol/μl after purification.
Amplification of these primers by PCR was performed as follows. Human fetal brain originated cDNA mixed solution (QUICK-Clone cDNA, CLONTECH Inc., U.S.A.) 1 μl was used. 10× buffer solution [500 mM KCl, 100 mM Tris-HCl (pH 8.3), 15 mM MgCl 2 , 0.01% gelatin] 5 μl, dNTP mixture (Takara Shuzo Co., Japan) 4 μl, sense primer DLTS1 (100 pmol/μl) 5 μl which was specific to the above vertebrates and antisense primer DLTA2 (100 pmol/μl) 5 μl and TaqDNA polymerase (AmpliTaq, Takara Shuzo Co., Japan, 5 U/μl) 0.2 μl were added thereto, and finally deionized water was added to set up total 50 μl. PCR was performed by 5 cycles of a cycle consisting of treatment at 95° C. for 45 seconds, at 42° C. for 45 seconds and 72° C. for 2 minutes, further 35 cycles of a cycle consisting of treatment at 95° C. for 45 seconds, at 50° C. for 45 seconds and 72° C. for 2 minutes, and finally allowed to stand at 72° C. for 7 minutes. A part of the PCR products was subjected to 2% agarose gel electrophoresis, stained with ethidium bromide (Nippon Gene Co., Japan), and observed under ultraviolet light to confirm amplification of about 400 bp DNA.
Total amount of PCR product was subjected to electrophoresis with 2% agarose gel prepared by low melting point agarose (GIBCO BRL Inc., U.S.A.), stained by ethidium bromide, cutting out about 400 bp bands of PCR products by the Delta primer under the UV light, adding distilled water of the same volume of the gel, heating at 65° C. for 10 minutes, and completely dissolving the gel. The dissolved gel was centrifuged at 15000 rpm for 5 minutes to separate supernatant solution after adding equal volume of TE saturated phenol (Nippon Gene Co., Japan) and the same separation operation was performed after adding TE saturated phenol: chloroform (1:1) solution and chloroform. DNA was recovered from the final solution by ethanol precipitation.
A vector, pCRII vector (Invitorogen Inc., U.S.A., hereinafter designates as pCRII) was used. The vector and the above DNA in molar ratio of 1:3 were mixed and DNA was ligated into the vector by using T4 DNA ligase (Invitorogen Inc., U.S.A.). The pCRII, to which DNA was integrated, was subjected to gene transduction into E. coli one shot competent cells (Invitorogen Inc., U.S.A.) and was spread on the semi-solid medium plate of L-Broth (Takara Shuzo Co., Japan) containing ampicillin (Sigma Corp., U.S.A.) 50 μg/ml and allowed to stand at 37° C. for about 12 hours. The resulting colonies were randomly selected, inoculated in the L-Broth liquid medium 2 ml containing same concentration of ampicillin and shake cultured at 37° C. for about 18 hours. The cultured bacterial cells were recovered and the plasmid was separated by using Wizard Miniprep (Promega Inc., U.S.A.) according to the attached explanation sheet. The plasmid was digested by restriction enzyme EcoRI. Integration of the said PCR product was confirmed by incision of about 400 bp DNA. Base sequence of the incorporated DNA in the confirmed clone was determined by the fluorescent DNA sequencer (Model 373S. Applied System Inc., U.S.A.)
Example 2
Cloning of Full Length Novel Human Delta-1 and its Analysis
A screening of clones having full length cDNA was performed by hybridization from human placenta origin cDNA library (inserted cDNA in λgt-11, CLONTECH Inc., U.S.A.) in plaques corresponding to 1×10 6 plaques. Generated plaques were transfered onto nylon filter (Hybond N+: Amersham Inc., U.S.A.). The transcribed nylon filter was subjected to alkaline treatment [allow to stand for 7 minutes on the filter paper permeated with a mixture of 1.5 M NaCl and 0.5 M NaOH], followed by two neutralizing treatments [allow to stand for 3 minutes on the filter paper permeated with a mixture of 1.5 M NaCl, 0.5 M Tris-HCl (pH 7.2) and 1 mM EDTA]. Subsequently, the filter was shaken for 5 minutes in the 2-fold concentrated SSPE solution [0.36 M NaCl, 0.02 M sodium phosphate (pH 7.7) and 2 mM EDTA], washed and air-dried. Then the filter was allowed to stand for 20 minutes on the filter paper, which was permeated with 0.4 M NaOH, shaken for 5 minutes with 5-fold concentrated SSPE solution and washed, then again air-dried. Screening was conducted in the human Delta-1 probe labeled with radioisotope 32 P using these filters.
DNA probe prepared in Example 1 was labeled with 32 P as follows. A DNA fragment was cutted out by EcoRI from pCRII , inserted a purified PCR product (about 400 bp) by human Delta-1 primer and determined gene sequence, and was isolated from low melting point agarose gel. The thus obtained DNA fragment was labeled by DNA labeling kit (Megaprime DNA labeling system: Amersham, U.S.A.). The primer solution 5 μl and deionized water were added to DNA 25 ng to set up total volume of 33 μl, which was treated for 5 minutes in boiling water bath. Reaction buffer solution 10 μl containing dNTP, α- 32 P-dCTP 5 μl and T4 DNA polynucleotide kinase solution 2 μl were added thereto, treated at 37° C. for 10 minutes in water bath. Subsequently, the mixture was purified by Sephadex column (Quick Spin Column Sephadex G-50: Boehringer Mannheim Inc., Germany), then treated for 5 minutes in boiling water bath and ice-cooled for 2 minutes for use.
Hybridization was performed as follows. The prepared filter hereinabove was immersed into the prehybridization solution consisting of SSPE solution, in which final concentration of each component is set at 5-fold concentration, 5-fold concentration of Denhardt's solution (Wako Pure Chemicals, Japan), 0.5% SDS (sodium dodecyl sulfate, Wako Pure Chemicals, Japan) and salmon sperm DNA (Sigma, U.S.A.) 10 μg/ml denatured by boiling water, and shaken at 65° C. for 2 hours, then the filter was immersed into the hybridization solution of the same composition with the above prehybridization solution with the 32 P-labeled probe above mentioned and shaken at 65° C. for 2 hours for 16 hours to perform hybridization.
The filter was immersed into SSPE solution containing 0.1% SDS, shaken at 55° C. and washed twice, further immersed into 10-fold dilution of SSPE solution containing 0.1% SDS and washed four times at 55° C. An autoradiography of the washed filter was performed using intensified screen. Clones of strongly exposed part were collected and the plaques obtained were again spread and screened by the same method hereinbefore to separate complete single clones.
The thus isolated phage clones were seven clones. Phage of all of these clones was prepared to about 1×10 9 pfu, purified the phage DNA, digested by restriction enzyme EcoRI and inserted into pBluescript (Stratagene Inc., U.S.A.) which was digested EcoRI in the same way. DNA sequences of the both ends of these clones were analyzed by DNA sequencer. Three clones of D5, D6 and D7 were the clone containing DNA sequence from No. 1 to 2244 in the sequence listing, SEQ ID NO: 8. A clone D4 was a clone containing DNA sequence from No. 999 to 2663 in the sequence listing, SEQ ID NO: 8. The clones D5 and D4 prepared the deletion mutant by using kilosequence deletion kit (Takara Shuzo Co., Japan) according to a description of the attached paper. Full-length cDNA base sequence of the present invention was determined using the DNA sequencer from both direction of 5′-direction and 3′-direction.
By applying with XhoI site at No. 1214 in DNA sequence in the sequence listing, SEQ ID NO: 8, D4 and D5 were digested by restriction enzyme XhoI to prepare plasmid pBSDel-1 containing full length of DNA sequence in the sequence listing, SEQ ID NO: 8.
Example 3
Cloning of Human Serrate-1 Specific PCR Product and Determination of Base Sequence
A mixed primer, which corresponded to amino acid sequence conserved in Drosophila Serrate and rat Jagged, i.e. sense primer SRTS 1 (the sequence listing, SEQ ID NO:16) and antisense primer SRTA2 (the sequence listing, SEQ ID NO:17), was used. Preparation was conducted by the same way as described in Example 1.
Amplification by PCR using these primers was performed as follows. To the human fetal brain originated cDNA mixed solution hereinbefore 1 μl was added 10× buffer solution (described in Example 1) 5 μl, said dNTP mixture 4 μl, sense primer SRTS1 (100 pmol/μl) 5 μl and antisense primer SRTA2 (100 pmol/μl) 5 μl specific to Serrate-1 homologue hereinbefore, and said TaqDNA polymerase 0.2 μl, and finally added deionized water to set up total volume 50 μl. The mixture was treated for 5 cycles of a cycle consisting of at 95° C. for 45 seconds, at 42° C. for 45 seconds and 72° C. for 2 minutes, and 35 cycles of a cycle consisting of at 95° C. for 45 seconds, at 50° C. for 45 seconds and 72° C. for 2 minutes, and finally allowed to stand at 72° C. for 7 minutes to perform PCR. A part of the PCR product was subjected to 2% agarose gel elctrophoresis, stained by ethidium bromide, and observed under ultraviolet light to confirm amplification of about 500 bp cDNA.
Total amount of PCR product was subjected to electrophoresis with 2% agarose gel prepared by low melting point agarose, stained by ethidium bromide, cutting out about 500 bp bands under the UV light, adding distilled water of the equal volume of the gel, heating at 65° C. for 10 minutes, and completely dissolving the gel. The dissolved gel was centrifuged at 15000 rpm for 5 minutes to separate supernatant solution after adding equal volume of TE saturated phenol and the same separation operation was performed after adding TE saturated phenol:chloroform (1:1) solution and chloroform. DNA was recovered from the final solution by ethanol precipitation.
A vector, pCRII vector was used. The vector and the above DNA were mixed in molar ratio of 1:3 and DNA fragment was ligated into the vector pCRII by the same method in Example 1. The pCRII, to which DNA was integrated, was subjected to gene transduction into E. coli . The resulting colonies were randomly selected and were inoculated in liquid medium L-Broth 2 ml containing the same concentration of ampicillin and shake cultured at 37° C. for about 18 hours. The cultured bacterial cells were recovered and the plasmid was separated by using the Wizard Miniprep according to the attached explanatory sheet. The plasmid was digested by restriction enzyme EcoRI. Integration of the said PCR product was confirmed by incision of about 500 bp DNA. Base sequence of the incorporated DNA in the confirmed clone was determined by the fluorescent DNA sequencer.
Example 4
Cloning of Full Length Novel Human Serrate-1 and its Analysis
A screening of clones having full length cDNA was performed by hybridization from the human placenta origin cDNA library hereinbefore in plaques corresponding to 1×10 6 plaques. Preparation of the filter was performed by the same method as described in Example 2. Screening was conducted in the human Serrate-1 probe labeled with radioisotope 32 P using the filter.
The above DNA probe labeled with 32 P was prepared by a method described in Example 2, and hybridization, washing of the filter and isolation of the clone were performed by the description in Example 2.
The thus isolated phage clones were 22 clones. Phage of all of these clones was prepared to about 1×10 9 pfu, purified the phage DNA, digested by restriction enzyme EcoRI and inserted into pBluescript which was digested EcoRI in the same way. DNA sequences of the both ends of these clones were analyzed by DNA sequencer. Two clones of S16 and S20 were the clone containing DNA sequence from No. 1 to 1873 in the sequence listing, SEQ ID NO: 10. Two clones S5 and S14 were the clones containing DNA sequence from No. 990 to 4005 in the sequence listing, SEQ ID NO:10. These clones prepared the deletion mutants by using the kilosequence deletion kit according to a description of the attached leaflet. The cDNA base sequence coding the polypeptide of the present invention was determined using the DNA sequencer from both direction of 5′-direction and 3′-direction.
By applying with BglII site at No. 1293 in DNA sequence in the sequence listing, SEQ ID NO: 10. S20 and S5 were digested by restriction enzyme BglII, and DNA of gene sequence from No. 1 to 4005 in the sequence listing SEQ ID NO: 10 was subcloned in E. coli vector pBluescript. This plasmid is named as pBSSRT.
Since the termination codon was not found in the C-terminal and the intracellular region coding C-terminal amino acids was not cloned, cloning of the full length gene was performed using the 3′ RACE system kit, GIBCO-BRL, U.S.A., according to the description of the attached leaflet. The cloning of cDNA gene for 3′-direction was performed in polyA + RNA (CLONTECH Inc., U.S.A.) originated from human placenta to determine the gene sequence.
The thus cloned three gene fragments by applying with BglII site in DNA sequence No. 1293 and AccI site in DNA sequence No. 3943 and a plasmid containing full length of DNA sequence in the sequence listing, SEQ ID NO: 5 were inserted between EcoRI and XbaI in the multi-cloning site of pUC18 to prepare pUCSR-1 containing full length gene of human Serrate-1. This gene sequence as well as its amino acid sequence is shown in the sequence listing, SEQ ID NO: 10.
Example 5
Preparation of Expression Vectors of Human Delta-1
Using the gene consisting of DNA sequence described in the sequence listing, SEQ ID NO: 7, expression vectors of human Delta-1 protein mentioned in the following 1)–5) were prepared. Addition of restriction enzyme sites and insertion of short gene sequence were performed using ExSite PCR-Based Site-Directed Mutagenesis Kit (Stratagene Inc., U.S.A.) according to the operating manual.
1) Expression Vector of Soluble Human Delta-1 Protein (HDEX)
The cDNA coding polypeptide of amino acid sequence form No. 1 to 520 in the sequence listing, SEQ ID NO: 3 was ligated with expression vector pMKITNeo containing SRα promoter and neomycin resistance gene to prepare expression vector.
For preparation of expression vector of human Delta-1, in order to stable expression from gene product, EcoRI site was added in the 20 bp upper stream for 5′-direction of the initiation codon (gene sequence No. 179 in the sequence listing, SEQ ID NO: 8). Using the above Mutagenesis Kit, a plasmid pBSDel-1, which contained DNA sequence in sequence listing, SEQ ID NO: 8 and full length cDNA of human Delta-1 were set as the template, and oligonucleotides having gene sequence in sequence listing, SEQ ID NO:18 and SEQ ID NO:19 was set as the primers. Then DNA adding EcoRI site in the 20 bp upper stream for 5′-direction was prepared. Hereinafter this plasmid is designated as pBS/Eco-Delta.
The pBS/Eco-Delta was used as a template. In order to add the termination codon and restriction enzyme MluI site after a C-terminal position, using the Mutagenesis Kit, and setting oligonucleotides having gene sequences in the sequence listing, SEQ ID NO:20 and SEQ ID NO: 21 as primers, addition of the termination codon and MluI site were performed. The resulted vector was digested by EcoRI and MluI, and about 1600 bp splitted gene fragment was ligated in pMKITNeo, which was treated by the same restriction enzyme, to construct the expression vector. This vector was designated as pHDEX.
2) Expression Vector of FLAG Chimera Protein of Soluble Human Delta-1 (HDEXFLAG)
The cDNA coding chimera protein, to which cDNA coding FLAG sequence was added to the C-terminal of polypeptide from No. 1 to 520 of amino acid sequence in the sequence listing, SEQ ID NO: 3, was ligated to the expression vector pMKITNeo containing SRα promoter and neomycin resistance gene to prepare the expression vector.
Using pBS/Eco-Delta as template, FLAG sequence was added in the extracellular C-terminal, i.e. after Gly at No. 520 in the sequence listing, SEQ ID NO: 3. In order to add the termination condon and restriction enzyme MluI site, using the Mutagenesis Kit, and setting oligonucleotides having gene sequence in the sequence listing, SEQ ID NO:22 and SEQ ID NO:21 as primers, a gene coding FLAG sequence and termination codon and MluI site were added in the C-terminal. This vector was digested by EcoRI and MluI, and about 1700 bp splitted gene fragment was ligated to the similarly restriction enzyme treated pMKITNeo to construct the expression vector. This vector was designated as pHDEXFLAG.
3) Expression Vector of IgG1Fc Chimera Protein of Soluble Human Delta-1 (HDEXIg)
A gene sequence coding polypeptide, to which amino acid sequence of Fc region below the hinge part of human IgG1 was added to the C-terminal of polypeptide having amino acid sequence in the sequence listing, SEQ ID NO: 3.
Preparation of fused protein with immunoglobulin Fc protein was performed according to the method of Zettlmeissl et al. (Zettlmeissl et al., DNA cell Biol., 9, 347–354, 1990). A gene using genome DNA with intron was applied and the said gene was prepared by using PCR. Human genome was used as a template. An oligonucleotide of the sequence in the sequence listing, SEQ ID NO: 23 with restriction enzyme BamHI site and an oligonucleotide of the sequence in the sequence listing, SEQ ID NO: 24 with restriction enzyme XbaI site were used as primers. PCR was performed using the primers and human genomic DNA as template. About 1.4 kbp band was purified, treated by restriction enzyme BamHI and XbaI (Takara Shuzo Co., Japan), and genes were ligated to pBluescript, which was similarly treated by restriction enzyme, by using T4 DNA ligase to prepare subcloning. Later, the plasmid DNA was purified and sequenced to confirm gene sequence, then the said gene sequence was confirmed as genomic DNA in the hinge region of heavy chain of the human IgG1. (The sequence is referred to Kabat et al., Sequence of Immunological Interest, NIH Publication No. 91-3242, 1991). Hereinafter this plasmid is designated as pBShIgFc.
Using the said pBS/Eco-Delta as template, and using the Mutagenesis Kit, restriction enzyme BamHI site was added in the extracellular C-terminal, i.e. after Gly at No. 520 in the sequence listing, SEQ ID NO: 3. Furthermore, in order to add restriction enzyme XbaI and MluI sites to the downstream, and setting the oligonucleotides having gene sequence in the sequence listing, SEQ ID NO: 25 and SEQ ID NO: 26, using the Mutagenesis Kit, BamHI, XbaI and MluI sites were added. This vector digested by XbaI and BamHI and about 1200 bp of gene fragment digested from the above pBShIgFc by XbaI and BamHI were ligated to prepare vector containing gene fragments coding the final objective soluble human Delta-1 IgG1Fc chimera protein. Finally, this vector was digested by EcoRI and MluI and about 3000 bp splitted gene fragments were ligated with the similarly restriction enzyme treated pMKITNeo to construct the expression vector. This vector was designated as pHDEXIg.
4) Expression Vector of Full Length Human Delta-1 Protein (HDF)
The cDNA coding polypeptide from No. 1 to 702 of amino acid sequence in the sequence listing, SEQ ID NO: 4, was ligated to the expression vector pMKITNeo containing SRα promoter and neomycin resistance gene to prepare the expression vector.
In order to add the termination codon in C-terminal of the full length sequence, i.e. after Val at No. 702 in the sequence listing, SEQ ID NO: 4 and restriction enzyme MluI site, using the Mutagenesis Kit and pBS/Eco-Delta as template and setting oligonucleotides having gene sequence in the sequence listing, SEQ ID NO: 27 and SEQ ID NO: 28 as primers, the termination codon and MluI site were added in the C-terminal. This vector was digested by EcoRI and MluI, and about 2200 bp splitted gene fragment was ligated to the similar restriction enzyme treated pMKITNeo to construct the expression vector. This vector was designated as pHDF.
5) Expression Vector of FLAG Chimera Protein (HDFLAG) of Full Length Human Delta-1
The cDNA coding chimera protein, to which cDNA coding FLAG sequence was added to the C-terminal of polypeptide from No. 1 to 702 of amino acid sequence in the sequence listing, SEQ ID NO: 4, was ligated to the expression vector pMKITNeo containing SRα promoter and neomycin resistance gene to prepare the expression vector.
In order to add FLAG sequence in the C-terminal, the termination codon and restriction enzyme MluI site, setting oligonucleotides having gene sequence in the sequence listing, SEQ ID NO: 29 and SEQ ID NO: 28 as primers and using pBS/Eco-Delta as template, a gene coding FLAG sequence and termination codon and MluI site were added in the C-terminal. From this vector, DNA coding full length of human Delta-1 was cloned in E. coli vector PUC19 to prepare vector pUCDL-1F coding full length of human Delta-1. This vector was digested by EcoRI and MluI, and about 2200 bp splitted gene fragments were ligated to the similar restriction enzyme treated pMKITNeo to construct the expression vector. This vector was designated as pHDFLAG.
Example 6
Preparation of Expression Vectors of Human Serrate-1
Using the gene consisting of DNA sequence described in the sequence listing, SEQ ID NO: 10 expression vectors of human Serrate-1 protein mentioned in the following 6)–10) were prepared. Addition of restriction enzyme sites and insertion of short gene sequence were performed by using the ExSite PCR-Based Site-Directed Mutagenesis Kit as well as according to the operating manual.
6) Expression Vector of Soluble Human Serrate-1 Protein (HSEX)
The cDNA coding polypeptide of amino acid sequence form No. 1 to 1036 in the sequence listing, SEQ ID NO: 6 was ligated with expression vector pMKITNeo to prepare expression vector.
For preparation of expression vector of polypeptide expression cells having amino acid sequence from No. 1 to 1036 in the sequence listing, SEQ ID NO: 6, in order to express gene product more stably EcoRI site was added in the 10 bp upper stream region for 5′-direction of the initiation codon (gene sequence No. 409 in the sequence listing, SEQ ID NO; 10). Using the above Mutagenesis Kit, a plasmid pBSSRT, which contained cDNA of human Serrate-1 from No. 1 to 4005 of DNA sequence in the sequence listing, SEQ ID NO:10, was set as the template, and oligonucleotide having gene sequence in sequence listing, SEQ ID NO:30 and oligonucleotide having gene sequence in sequence listing, SEQ ID NO:31 were set as the primers. Then DNA adding EcoRI site in the 10 bp upper stream for 5′- direction was prepared.
The thus prepared vector (hereinafter designates as pBS/Eco-Serrate-1) was used as a template. In order to add the termination codon and further restriction-enzyme MluI site in the extracellular C-terminal region, i.e. C-terminal of polypeptide in the sequence listing, SEQ ID NO: 6, using the Mutagenesis Kit, and setting oligonucleotide having gene sequence in the sequence listing, SEQ ID NO: 32 and oligonucleotide having gene sequence in the sequence listing, SEQ ID NO: 33, as primers, the termination codon and MluI site were added. The resulting vector was digested by EcoRI and MluI, and about 3200 bp splitted gene fragment was ligated in pMKITNeo, which was treated by the same restriction enzyme, to construct the expression vector. This vector was designated as pHSEX.
7) Expression Vector of FLAG Chimera Protein of Soluble Human Serrate-1 (HSEXFLAG)
The cDNA-coding FLAG chimera protein, which had FLAG sequence in the C-terminal of polypeptide from No. 1 to 1036 of amino acid sequence in the sequence listing, SEQ ID NO: 6, was ligated to the expression vector pMKITNeo containing SRα promoter and neomycin resistance gene to prepare the expression vector.
Using pBS/Eco-Serrate-1 as a template, FLAG sequence was added in the extracellular C-terminal, i.e. the C-terminal of polypeptide in the sequence listing, SEQ ID NO: 6. In order to add the termination codon and further restriction enzyme MluI site, using the Mutagenesis Kit, and setting oligonucleotide having gene sequence in the sequence listing, SEQ ID NO: 34 and oligonucleotide having gene sequence in the sequence listing, SEQ ID NO: 33 as primers, a gene coding FLAG sequence and termination codon and MluI site were added in the C-terminal. This vector was digested by EcoRI and MluI, and about 3200 bp splitted gene fragment was ligated to the similarly restriction enzyme treated pMKITNeo to construct the exprssion vector. This vector was designated as pHSEXFLAG.
8) Expression Vector of IgG1Fc Chimera Protein of Soluble Human Serrate-1 (HSEXIg)
A gene sequence coding polypeptide, to which amino acid sequence of Fc region below the hinge part of human IgG1 was added to the C-terminal of polypeptide having amino acid sequence in the sequence listing, SEQ ID NO: 6.
In order to add restriction enzyme BamHI site in the extracellular C-terminal, i.e. after the polypeptide having the sequence in the sequence listing, SEQ ID NO: 6 and further restriction enzyme XbaI and MluI sites to its downstream, BamHI, XbaI and MluI sites were added Using PBS/Eco-Serrate-1 as a template by the Mutagenesis Kit, using oligonucleotide having gene sequence in the sequence listing, SEQ ID NO:35 and oligonucleotide having gene sequence in the sequence listing, SEQ ID NO: .36 as primers. This vector digested by XbaI and BamHI and about 1200 bp of gene fragment digested from the above pBShIgFc by Xba-I and BamHI were ligated to finally prepare a vector, which contained gene fragments coding IgG1Fc chimera protein of the soluble human Serrate-1. Finally, this vector was digested by EcoRI and MluI, and splitted about 4400 bp gene fragment was ligated to pMKITNeo to construct the expression vector. This vector was designated as pHSEXIg.
9) Expression Vector of Full Length Human Serrate-1 Protein (HSF)
The cDNA coding polypeptide from No. 1 to 1187 of amino acid sequence in the sequence listing, SEQ ID NO: 7 was ligated with expression vector pMKITNeo containing SRα promoter and neomycin resistance gene to prepare expression vector.
For preparation of the full length expression vector about 900 bp splitted gene fragment from pBS/Eco-Serrate-1 digested by restriction enzyme EcoRI and BglII, and pUCSR-1 digested by the same restriction enzyme were ligated, and a vector pUC/Eco-Serrate-1 coding full length gene of human Serrate-1 was prepared.
In order to add the termination codon to the site after Val at No. 1187 in the sequence listing, SEQ ID NO: 7, and further add the restriction enzyme MluI site, using the Mutagenesis Kit, the termination codon and MluI site were added to the C-terminal using oligonucleotides having gene sequence in the sequence listing, SEQ ID NO:37 and SEQ ID NO:38 as primers and the pBS/Eco-Serrate-1 as a template. The resulting vector was digested by EcoRI and MulI, and about 3700 bp splitted gene fragments were ligated in pMKITNeo, which was treated by the same restriction enzyme, to construct the expression vector. This vector was designated as pHSF.
10) Expression Vector of FLAG Chimera Protein of Full Length Human Serrate-1 (HSFLAG)
The cDNA coding chimera protein, to which cDNA coding FLAG sequence was added in the C-terminal of polypeptide from No. 1 to 1187 of amino acid sequence in the sequence listing, SEQ ID NO: 7, was ligated to the expression vector pMKITNeo containing SRα promoter and neomycin resistance gene to prepare the expression vector.
In order to add FLAG sequence in the C-terminal the termination codon and further restriction enzyme MluI site, setting oligonucleotides having gene sequence in the sequence listing, SEQ ID NO: 39 and SEQ ID NO: 38 as primers, using pBS/Eco-Serrate-1 as a template a gene coding FLAG sequence, the termination codon and the MluI site were added in the C-terminal as same as similar manner. This vector was digested by EcoRI and MluI, and about 3700 bp splitted gene fragments were ligated to the similarly restriction enzyme treated pMKITNeo to construct the expression vector. This vector was designated as pHSFLAG.
Example 7
Expression and Gene Transfer of the Expression Vectors into Cells
The expression vectors prepared in Examples 5 and 6 were transduced into COS-7 cell (obtained from RIKEN Cell Bank, Physical and Chemical Research Institute, Japan, RCB0539).
Cell culture before gene transduction was performed by culturing in D-MEM (Dulbecco modified Eagle's medium, GIBCO-BRL Inc. U.S.A.) 10% FCS. On a day before gene transduction, medium of cells was changed to set cell counts 5×10 5 cells/ml and cultured for overnight. On the day of gene transduction, cells were sedimented by centrifugation, centrifugally washed twice with PBS(−) and prepared the cells to 1×10 7 cells/ml in 1 mN MgCl 2 and PBS(−). Gene transfer was performed by electroporation using gene transduction device Gene-pulsar (Bio-Rad Inc., U.S.A.). The above cell suspension 500 μl was collected in the cell for electroporation (0.4 cm), added expression vector 20 μg, and allowed to stand in ice for 5 minutes. Electroporation was performed under the condition 3 μF. 450 V twice, during the twice electroporation cell mixture was allowed to stand at room temperature. After 5 minutes stayed in ice, cells were spread in the culture medium, diameter 10 cm previously added 10 ml of medium, and cultured at 37° C. in 5% carbon dioxide incubator.
The next day, the culture supernatant solution was removed, washed the cells adhered to the dish twice with PBS(−) 10 ml. In case of expression vector pHDEX, pHDEXFLAG, pHDEXIg, pHSEX, pHSEXFLAG, and pHSEXIg, serum-free D-MEM 10 ml was added and cultured for 7 days. Culture supernatant solution was recovered and was replaced the buffer to PBS(−) by Centricon 30 (Amicon Inc., U.S.A.) and simultaneously the solution was concentrated to 10-fold to obtain cell culture supernatant solution.
In case of pHDF, pHDFLAG, pHSF, and pHSFLAG, medium was changed by D-MEM containing 10% FCS, and cultured further 3 days to prepare cell lysate. Thus, 2×10 6 cells were suspended in the cell lysis buffer [50 mN Hepes (pH 7.5), 1% Triton X100, 10% glycerol, 4 mN EDTA, 50 μg/ml Aprotinin, 100 μM Leupeptin, 25 μM Pepstatin A and 1 mM PMSF] 200 μl, allowed to stand in ice for 20 minutes and centrifuged at 14000 rpm for 20 minutes to remove supernatant solution to obtain cell lysate.
Expression of proteins were detected by Western blotting.
Concentrated cultured supernatants or cell lysates were subjected to SDS-PAGE using an electrophoresis tank and polyacrylamide gel for SDS-PAGE (gradient gel 5–15%) (ACI Japan Inc., Japan) according to the manufacturer's construction. Samples were prepared by treatment in boiling water for 5 min. with 2-mercaptoethanol (2-ME) for reduction, and non-reduced condition without taking the above treatment. As a marker, Rainbow Marker (high molecular weight, Amersham Inc.) was used. Sample buffer solution and electrophoresis buffer were prepared with reference to the attached leaflet. When the SDS-PAGE was finished, acrylamide gel was transcribed to PVDF membrane filter (BioRad Inc., U.S.A.) using the Mini Trans Blot Cell (BioRad Inc.).
The thus prepared filter was shaken overnight at 4° C. in the Blockace (Dainippon Pharm. Co., Japan), TBS-T [20 mM Tris, 137 mM NaCl (pH 7.6) and 0.1% Tween 20] to blocking. According to the explanation of the attached leaflet of ECL Western blotting detection system (Amersham Inc., U.S.A.); in case that the objective protein was human Delta-1 origin, anti-human Delta-1 mouse monoclonal antibody described in Example 9 was used as primary antibody; in case that protein was human Serrate-1 origin, anti-human Serrate-1 mouse monoclonal antibody described in Example 9 was used as primary antibody; and in case that protein was FLAG chimera, anti-FLAG M2 mouse monoclonal antibody (Eastman Kodak, U.S.A.) was used as primary antibody, and peroxidase labeled anti-mouse Ig sheep antibodies (Amersham Inc., U.S.A.) was reacted. In case of IgG chimera, peroxidase labeled anti-human Ig sheep antibodies (Amersham Inc., U.S.A.) was reacted.
Reaction time for antibodies was 1 hour at room temperature, and at an interval of each reaction, washing was performed by shaking in TBS-T at room temperature for 10 minutes for three times. After the final washing, the filter was immersed in the reaction solution of ECL-Western blotting detection system (Amersham Inc., U.S.A.) for 5 minutes, and wrapped in polyvinylidene chloride wrap to expose X-ray film.
As the result, in the sample with treatment of reduction, the bands showing protein obtained by transduction of pHDEX and pHDEXFLAG was deteted about 65 kD; protein obtained by transduction of pHDEXIg was detected about 95 kD, and protein obtained by transduction of pHDF and pHDFLAG was detected about 85 kD. In the non-reduced sample, the bands showing protein obtained by transduction of pHDEXIg was detected slightly smeared bands at 120 kD to 200 kD, mainly about 180 kD, which showed about 2-fold of the reduction stage, consequently, dimer was formed.
And also, in the sample with treatment of reduction, the bands showing protein obtained by transduction of pHSEX and pHSEXFLAG was detected about 140 kD; protein obtained by transduction of pHSEXIg was detected about 170 kD, and protein obtained by transduction of pHSF and pHSFLAG was detected about 150 kD. In the non-reduced sample, the bands showing protein obtained by transduction of pHSEXIg was detected slightly smeared bands at 250 kD to 400 kD, mainly about 300 kD, which showed about 2-fold of the reduction stage, consequently, dimer was formed.
In these experiments, however cell lysate and cultured supernatant of COS-7 cells, to which pMKITNeo vector was transduced as a control was tested, no bands reacted against anti-human Delta-1 mouse monoclonal antibody, anti-human Serrate-1 mouse monoclonal antibody, anti-FLAG antibody, and anti-human Ig antibody were detected.
Therefore, this ten-expression vector can produce the objective polypeptides.
Example 8
Purification of Soluble Human Delta-1 and Human Serrate-1 Proteins of Gene Transduction Cells
Cultured supernatant of COS-7 cells consisting of HDBXFLAG, HDBXIg, HSEXFLAG and HSEXIg, all of which expression was detected by a method in Example 7, were prepared on large scale, and each chimera protein was purified by affinity column chromatography.
In case of HDEXFLAG and HSEXFLAG, 2 liter of the cultured supernatant obtained by the method in Example 7 was passed through a column packed with Anti-FLAG M2 Affinity Gel (Eastman Kodak, U.S.A.). The chimera protein was adsorbed in a column by a reaction of affinity of anti-FLAG antibody of the gel and FLAG sequence of the chimera protein. Column, inner diameter 10 mm, disposable column (BioRad Inc., U.S.A.) was used with packing the above gel 5 ml. A circulation system consisting of medium bottle→column→peristaltic pump→medium bottle was set up. The circulation was run by a flow 1 ml/min. for 72 hours. Thereafter the column was washed with PBS (−) 35 ml and eluted by 0.5 M Tris-glycine (pH 3.0) 50 ml. The eluate of 25 fractions, each 2 ml, was collected into the tube, and each fraction was neutralized by 200 μl of 0.5 M Tris-HCl (pH 9.5) previously added in each tube.
The eluate fraction, each 10 μl of the secretor FLAG chimera protein which was purified by the above method was subjected to reduction treatment described in Example 7. SDS-PAGE electrophoresis by 5–10% gradient polyacrylamide gel was performed. After finishing the electrophoresis, silver staining was conducted by using Wako silver stain kit II (Wako Pure Chemicals, Japan) according to the explanation of the attached leaflet. Fractions from No. 4 to 8 showed detectable bands in HSFLAG. The size is identical with the result of Western blotting of anti-FLAG antibody obtained in Example 6 in both of HDEXFLAG and HSEXFLAG. Therefore, purified HDEXFLAG and HSEFLAG were obtained.
In the IgG1Fc chimera protein, i.e. HDEXIg and HSEXIg, the cultured supernatant solution 2 liter was adsorbed in Protein A Sepharose colulnn (Pharmacia Inc., Sweden) according to the same method as of FLAG chimera protein to collect the eluate fractions. Using a part of eluate as same as in FLAG chimera protein, a determination of the eluate fraction, identification of the size and detection of the purity were performed by SDS-PAGE electrophoresis and silver staining in the reduced condition. Therefore, the eluate fraction from No. 4 to 15 were the detected bands. The size thereof is identical with the result of Western blotting using anti-human Ig antibody in both of HDEXIg and HSEXIg. Therefore, purified HDEXIg and HSEXIg were obtained.
Example 9
Preparation of Antibodies Recognizing Human Delta-1 and Human Serrate-1
HDEXFLAG and HSEXFLAG, purified by the method in Example 8, were used as immunogen, and rabbits were immunized. After assaying antibody titer, whole blood was collected and serum was obtained. Anti-human Delta-1 rabbit polyclonal antibody and anti-human Serrate-1 rabbit polyclonal antibody were purified by using the econopack serum IgG purification kit (BioRad Inc., U.S.A.) with reference to the attached explanation leaflet.
HDEXFLAG and HSEXFLAG purified by a method described in Example 8 were used as Immunogens, and mouse monoclonal antibodies were prepared according to the explanation of the textbook. The purified HDEXFLAG or HSEXFLAG was administered in Balb/c mice (Nippon SLC CO., Japan) separately, 10 μg/mouse, immunized intracutaneously and subcutaneously. After second immunization increased serum titer was confirmed by collecting blood ophthalmologically, the third immunization was performed. Subsequently, the spleen of mice was collected and fused with mouse myeloma cells P3×63Ag8 (ATCC TIB9) using polyethylene glycol. Hybridoma was selected by HAT medium (Immunological and Biological Research Institute, Japan), and the hybridoma strains which produced antibody specifically recognizing extracellular region of human Delta-1 or human Serrate-1 in the medium, were isolated by enzyme immunoassay. The hybridoma strains producing mouse monoclonal antibody, which specifically recognized human Delta-1 or human Serrate-1 were established.
Anti-human Delta-1 monoclonal antibody and anti-human Serrate-1 monoclonal antibody were purified and prepared by using Mab Trap GII (Pharmacia Inc. Sweden) and according to the explanation of the leaflet, from the supernatant of the thus established hybridoma.
Affinity column was prepared by using these monoclonal antibodies. Preparation of the affinity column was performed according to the explanation attached to the CNBr activated Sephadex 4B (Pharmacia Inc., Sweden). A column, 2 cm 2 ×1 cm. containing gel 2 ml, was prepared.
A concentrated solution of the supernatant of the cultured COS-7 cells, to which pHDEX was gene transduced, was passed through the column for which anti-human Delta-1 monoclonal antibody was bound. A concentrated solution of the supernatant of the cultured COS-7 cells, to which pHSEX was gene transduced, was passed through the column, for which anti-human Serrate-1 monoclonal antibody was bound. Each supernatant solution was passed at 20 ml/hr, subsequently PBS (−) 15 ml was passed at the same flow rate and washed the column. Finally, the products were eluted by a mixture of 0.1 M sodium acetate and 0.5 M NaCl (pH 4.0). The eluate, each 1 ml fraction, was collected, and was neutralized by adding 1M Tris-HCl (pH 9.1) 200 μl for each fraction.
SDS-PAGE of each purified protein was conducted under reduced condition according to the method described in Example 8, followed by silver staining and Western blotting to estimate molecular weight. HDEX, about 65 kD, was purified from concentrated supernatant of the cultured COS-7 cells, to which pHDEX was gene transduced, and HDSEX, about 140 kD, was purified from concentrated supernatant of the cultured COS-7 cells, to which pHSEX was gene transduced. Consequently, human Delta-1 and human Serrate-1 can be purified by these affinity columns.
Example 10
Effects of HDEXIg and HSEXIg to Colony Formation of Blood Undifferentiated Cells
In order to observe physiological action of HDEXIg and HSEXIg on blood undifferentiated cells, CD34 positive cells were cultured in the serum-free semi solid medium in the presence of HDEXIg and HSEXIg and known cytokines, and number of colony forming cells were observed.
Human umbilical cord blood or adult human normal bone marrow blood was treated by the silica solution (Immunological and Biological Research Institute, Japan) according to the attached explanation leaflet. Thereafter the low density cellular fraction (<1.077 g/ml) was fractionated by densitometric centrifugation of Ficoll pack (Pharmacia Inc., Sweden) to prepare mononuclear cells. CD34 positive cells of human umbilical cord blood or human normal bone marrow blood was isolated from the mononuclear cells.
Separation of CD34 positive cells was performed by using Micro-Selector System (AIS Inc., U.S.A.) or Dynabeads M-450 CD34 and DETACHa-BEADS CD34 (Dynal Inc., Norway) according to attached explanation leaflets. After separation, the purity was measured as follows. Cells were stained by FITC labeled CD34 antibody HPCA2 (Beckton-Deckinson Inc., U.S.A.) and examined by a flow-cytometer (FACSCalibur, Beckton-Deckinson. U.S.A.). Purity above 85% was confirmed for use.
The thus isolated CD34 positive cells were suspended homogeneously to form 400 cells/ml of the medium hereinbelow, and spread in the 35 mm dish (Falcon Inc., U.S.A.), then cultured for 2-weeks in carbon dioxide incubator at 37° C. under 5% carbon dioxide, 5% oxygen, 90% nitrogen and 100% humidity. The formed blood colonies were counted under the invert microscope.
A medium used is α-medium (GIBCO-BRL, U.S.A.), containing 2% deionized bovine serum albumin (BSA, Sigma, U.S.A.), 10 μg/ml human insulin (Sigma, U.S.A.) 200 μg/ml transferrin (Sigma, U.S.A.). 10 −5 M 2-mercaptoethanol (Nakarai Tesk Co., Japan), 160 μg/ml soybean lectin (Sigma, U.S.A.), 96 μg/ml cholesterol (Sigma, U.S.A.) and 0.9% methylcellulose (Wako Pure Chemicals, Japan).
To the above medium under the following three conditions of cytokines, human Delta-1 extracellular Ig chimera protein (HDEXIg) or human Serrate-1 extracellular Ig chimera protein (HSEXIg) were added to the final concentration of 1 μg/ml. For control, human IgG1 (Ahens Research and Technology Inc., U.S.A.) was added with the same concentration in order to observe effect of IgGFc region.
Conditions of cytokines are as follows.
1: 100 μg/ml, human SCF (Intergen Inc., U.S.A.), 10 ng/ml human IL-3 (Intergen Inc., U.S.A.), 100 ng/ml human IL-6 (Intergen Inc., U.S.A.) 2: 100 ng/ml human SCF, 10 ng/ml human IL-3, 4 ng/ml human thrombopoietin (Pepro Tech Inc., U.S.A.) 3: 100 ng/ml human SCF, 10 ng/ml human IL-3, 100 ng/ml-human IL-6, 2 U/ml Epo (Chugai Seiyaku Co., Japan) 10 ng/ml human G-CSF (Chugai Seiyaku Co., Japan)
Results are shown in FIG. 2 . In FIG. 2 , A is a case of human Delta-1 extracellular Ig chimera protein (HDEXIg), and B is a case of human Serrate-1 extracellular Ig chimera protein (HSEXIg). For A and B, each different origin human umbilical cord blood CD34 positive cell was used. The vertical axis: number of colonies. White: control, black: HDEXIg or HSEXIg. Both HDEXIg and HSEXIg have suppressive action of colony formation. No differences of the activities on the types of colonies were noted. Therefore, the molecular of the present invention has suppressive action for colony formation against colony forming cells of blood undifferentiated cells, i.e. diferentiation-suppressive action. Comparison with or without SCF on the activity indicated that the suppressive action tended to occur only in the presence of SCF.
Dose-dependent manner of the activity was studied. Comparison with dimer HSEXIg and monomer HSEXFLAG was performed. Result is shown in FIG. 3 . Concentration in this case is indicated as molar concentration. For comparison with dimer and monomer, dimer HSEXIg was indicated by exact two molar concentrations, and was plotted equivalent molar concentration of the human Serrate-1. Vertical axis indicates colony forming counts and horizontal axis indicates molar concentration. Colony forming counts without Notch ligand were plotted on the vertical axis in the zero concentration. For comparison, colony forming counts of human IgG1 1 μg/ml, was about 100 colonies.
This result indicated that HSEXIg and HSEXFLAG suppressed colony formation in dose-dependent manner. Activity of dimer HSEXIg was stronger than the monomer. A monomer HSEXFLAG showed stimulative action for colony formation in the low concentration area.
Example 11
Actions of HDEXIg and HSEXIg on Long Term Liquid Culture of Colony Forming Blood Undifferentiated Cells
For observing physiological action of HDEXIg and HSEXIg on the blood undifferentiated cells, umbilical cord blood CD34-positive cells were culture for long term in the serum-free liquid medium in the presence of HDEXIg or HSEXIg and known cytokines, and numbers of colony forming cells were observed.
The umbilical cord blood mononuclear CD34 positive cells separated by a method described in Example 10 were liquid cultured at 1000 cells/well in the 24 well cell culture plate (Falcon Inc., U.S.A.). Culture was performed at 37° C. in the carbon dioxide incubator under 5% carbon dioxide and 100% humidity. Liquid culture medium was Iscove's modified Dulbecco's medium (IMDM, GIBCO-BRL, U.S.A.) added with 2% BSA, 10 μg/ml human insulin, 200 μg/ml transferrin. 40 μg/ml low density lipoprotein (GIBCO-BRL, U.S.A.), 10 −5 M 2-mercaptoethanol, 50 ng/ml human SCF, 5 ng/ml human IL-3, 10 ng/ml human IL-6, 5 ng/ml human GM-CSF (Intergen Inc., U.S.A.), and 3 U/ml Epo. If necessary XDEXIg-500 ng HSEX1g or 50 ng/ml MIP-1 α (Intergen Inc., U.S.A.) was added. The medium was added 1 ml/well and half of the medium was changed three times in a week. After culturing 2, 4, 6 and 8 weeks, all cells were collected from wells by using cell scraper in 1.5 ml micro tube. Cells were precipitated by centrifugation and resuspended in a fresh IMDM 1 ml, counted the cell counts by using hemocytometer, and in 5000 cells/ml, blood cell colony forming assay was performed.
Blood cell colony forming assay was performed using the Iscove's methylcellulose complete ready mix (Stem Cell Technologies Inc., Canada), and each 1 ml was inoculated in two plates of 35 mm dish (Falcon Inc., U.S.A.) and incubated for 2 weeks in the carbon dioxide incubator. Blood colonies were counted CFU-GM and BFU-E in the invert microscope, and total was counted as CFU-C. CFU-C counts and cell counts obtained by hemocytometer were multiplied to obtain CFU-C count/1000 cells inoculated in the liquid culture.
In Table 1, result of HDEXIg and in Table 2, result of HSEXIg are shown. Experiments were conducted at n=3, values obtained were shown by (mean±SD). In the table, ND means no detection of colony.
TABLE 1
Colony forming cell maintenance action in the long-term
liquid culture of human Delta-1 of the present invention
Cytokines
Week
—
MIP-1 α
HDEXIg
0
69 ± 9
68 ± 9
68 ± 9
2
1440 ± 120
720 ± 110
1280 ± 230
4
340 ± 40
420 ± 80
410 ± 90
6
28 ± 6
96 ± 17
290 ± 60
8
ND
ND
88 ± 13
TABLE 2
Colony forming cell maintenance action in the long-term
liquid culture of human Serrate-1 of the present invention
Cytokines
Week
—
MIP-1 α
HSEXIg
0
68 ± 9
68 ± 9
68 ± 9
2
1440 ± 120
720 ± 110
1360 ± 280
4
340 ± 40
420 ± 80
560 ± 70
6
28 ± 6
96 ± 17
220 ± 50
8
ND
ND
130 ± 50
CFU-C could only be observed until 6 th week of cultivation under the condition without cytokines for maintaining undifferentiated condition, and under the condition with MIP-1α. It could be observed at 8 th week in the presence of HDEXIg or HSEXIg. In comparison with MIP-1α and HDEXIg and HSEXIg, MIP-1α strongly suppressed colony formation at 2 weeks of culture, however no suppression in HDEXIg and HSEXIg were observed. In maintenance of CFU-C counts at 6 and 8 weeks of culture, HDBXIg and HSEXIg were superior.
Example 12
Effects of HDEXIg and HSEXIg on Liquid Culture of Blood Undifferentiated Cell LTC-IC
In order to observing physiological action of HDEXIg and HSEXIg on the blood undifferentiated cells, umbilical cord blood CD34 positive cells were cultured for two weeks in the serum-free liquid medium in the presence of HDEXIg or HSEXIg and known cytokines, and numbers of LTC-IC, which was thought to be most undifferentiated blood cells at present were observed.
The umbilical cord blood monocyte CD34 positive cells, 100000 to 20000 cells, separated by a method described in Example 10 were cultured in the following medium for 2 weeks. Numbers of LTC-IC in 4 experimental groups, which include a group before cultivation, a group of HDEXIg, a group of HSEXIg and a control group, were determined. Media used in liquid culture medium were α-medium added with 2% BSA, 10 μg/ml human insulin, 200 μg/ml transferrin, 40 μg/ml low density lipoprotein, and 10 −5 M 2-mercaptoethanol, further added with 100 ng/ml human SCF, 10 ng/ml human IL-3, and 100 ng/ml human IL-6, HDEXIg or HSEXIg 1 μg/ml were added to the above medium. In the control group, human IgG1 was added in the equal concentration.
Preparation of human bone marrow stromal cell layer used for LTC-IC, and quantitative assay of frequency of LTC-IC by a limit dilution were performed according to a method of Sutherland et al. (Blood. 74, 1563-, 1989 and Proc, Natl. Acad. Sci, USA. 87, 3584-, 1990)
The bone marrow mononuclear cells, 1–2×10 7 cells, obtained in Example 10 before the separation and without the silica solution treatment, were cultured in LTC medium (MyeloCul, Stem Cell Technologies Inc., Canada) 5 ml added with hydrocortisone 1 μM (Upjohn Japan Co., Japan) in T-25 flask (Falcon Inc., U.S.A.) at 37° C. under 5% carbon dioxide and 100% humidity in the carbon dioxide incubator. Culture was conducted until the adhesive cell layers of the stromal cell formation spread more than 80% of the bottom area of the culture. Detachment of the cell layer was performed by treating with EDTA solution (Cosmobio Co., Japan). Cells were plated in the 96 well plate (Beckton-Deckinson Inc., U.S.A.), about 2×10 4 cells/well and re-cultivation was continued in the same medium. X-ray, 15Gy, 250 KV peak was irradiated after reconstituted stromal cell layer. Growth of stromal cells was stopped and blood cells in the stromal cells were removed by this treatment. The thus prepared stromal cells were used as stromal cell layer for the experiments.
In the assay of LTC-IC, cell counts in each group were adjusted within the ranges of 25–400 cells/well for CD34 positive cells before the cultivation, and 625–20000 cells/well for the cells after the cultivation, and cells were diluted for six step-dilution within these ranges. Each dilution step of cells was co-cultured with the above stromal cell layer in the 96 well plate, for 16 wells/cells of one dilution step. Culture was performed in the same medium as used in stromal formation, at 37° C. under 5% carbon dioxide and 100% humidity in the carbon dioxide gas incubator for 5 weeks. Cells in suspension and in attachment after cultivation were recovered in each well. Collected cells were transferred to the semi-solid culture medium consisting of α-medium added with 0.9% methylcellulose, 30% fetal calf serum (FCS, ICN Biomedical Japan), 1% BSA, 10 −5 M 2-mercaptoethanol, 100 ng/ml human SCF, 10 ng/ml human IL-3, 100 ng/ml human IL-6, 2 U/ml Epo and 10 ng/ml human G-CSF. After 2 weeks of cultivation, colony forming cells were detected as the same was as described in Example 10 and 11, and numbers of well, in which colony forming cells were found, were detected. Incidence of LTC-IC was calculated according to the method of Taswell et al. (J. Immunol. 126, 1614-, 1981) based on the above data.
Graph used for calculation is shown in FIG. 4 . In FIG. 4 , calculation curves after liquid culture is shown. A vertical axis shows ratio of well for no colonies were observed, and a horizontal axis shows number of cells/well. In each experimental group, numbers of well, for which colonies were not observed, and numbers of cells were plotted, then regression curve was calculated by the least square method. Number of cells corresponding to number of 0.37 (a reciprocal of a base of natural logarithm) for which colonies did not appeared, was calculated. A reciprocal of that number of cells is a frequency of LTC-IC. Further, absolute number of LTC-IC was calculated from initial number of cells and frequency of LTC-IC.
The result indicated that 243 LTC-IC were found in 25000 cells before the liquid culture. In the control group number of cells during 2 weeks of cultivation increased to 1,510,000 cells, and LTC-IC was decreased to 49 cells. However, culturing with human Delta-1, i.e. HDEXIg or human Serrate-1, i.e. HSEXIg, numbers of cells were maintained in 1,310,000 and 1,140,000, respectively, and numbers of LTC-IC were slightly decreased to 115 and 53. Consequently, polypeptide of the present invention, especially human Delta-1 could have an activity for maintenance of number of LTC-IC in the liquid culture.
Example 13
Binding of HDEXIg and HSEXIg for Blood Cells
Binding of Notch ligands with various blood cells was studied using specific binding of Notch ligands to Notch receptors.
Blood cell lines tested were Jurkat (ATCC TIB-152), Namalwa (ATCC CRL-1432), HL-60 (ATCC CRL-1964), K562 (ATCC CCL-243), THO-1 (ATCC TIB-2 02), UT-7 (Komatsu et al., Cancer Res., 51, 341–348, 1991), Mo7e (Avanzi et al. Br. J. Haematol., 69, 359-, 1988) and CMK (Sato et al. Exp. Hematol., 15, 495–502, 1987). Culturing media for these cells were found in the reference or ATCC CELL LIMES & HYBRIDOMAS, 8 th Ed. (1994).
Cells, 1×10 6 cells, were suspended in Hank's balanced salt solution containing 2% FCS and 10 mM Hepes. HDEXIg or HSEXIg 1 μg/ml were added therein and allowed to stand at 4° C. for overnight. Cells were washed twice with the Hank's solution. PE labeled sheep anti-human IgG monoclonal antibody 1 μg/ml was added, allow to stand in ice-cooling for 30 minutes, washed twice with the Hank's solution, and suspended in the Hank's solution 1 ml. Analysis was performed using the flow cytometer (FACSCalibur). Control groups were used with human IgG1 staining in place of HDEXIg or HSEXIg staining.
Results are shown in FIG. 5 . A vertical axis indicates cell counts and a horizontal axis indicates fluorescence intensity. Staining with HDEXIg or HSEXIg is shown by solid line and control, a staining with human IgG1 is shown by a broken line. In FIG. 5 , the left column shows HDEXIg and the right column shows HSEXIg. As shown in FIG. 5 , results indicate that Jurkat: reacted, Namalwa: non-reacted. HL-60: non-reacted, K562: non-reacted. THP-1: non-reacted, UT-7: reacted, Mo7e: non-reacted and CMK: reacted. Since the same results in HDEXIg and HSEXIg were obtained, both recognized the identical molecule and these cells can be differentiated.
EFFECT OF THE INVENTION
Notch ligand molecules of the present invention can be used for maintenance of undifferentiated-suppressive substances, and in the prepration of pharmaceuticals. | A polypeptide which contains the amino acid sequence described in SEQ ID NO: 1 in the Sequence Listing encoded by a gene originating in human being. Because of serving as a chemical efficacious in the suppression of the proliferation and differentiation of undifferentiated blood cells, this polypeptide is expected to be usable in medicines and medical supplies. | 0 |
FIELD OF INVENTION
This invention relates to a gearbox. It has particular, but not exclusive, application for use in a high-performance motor vehicle such as a sports car or a racing car.
BACKGROUND
A conventional manual automotive gearbox has one particular disadvantage when applied to a vehicle from which maximum performance is to be extracted: it is necessary to remove engine torque from the input to the gearbox when the gear ratio is to be changed, typically by interrupting drive through a friction clutch. This results in the acceleration of the vehicle being interrupted during the period for which the clutch is open. In a conventional gearbox, it is necessary to remove torque from immediately before a currently-selected gear is disengaged until a new gear is selected.
The most common arrangement in general automotive use mounts a gear onto a hub using a bearing or bush arrangement. The hub is joined to the gear shaft through a splined or similar coupling. Mounted on the hub is a sliding ring system which can slide on the hub to engage a gear in order to couple that gear to the hub for rotation, thus permitting drive to pass from the gear to the shaft. In some instances the hub may be integral with the gear shaft. The sliding ring system can be either a dog clutch ring or a synchronizer ring assembly; many different sizes and types are available. In a sequential gearbox, the sliding ring system is actuated by a selector fork, which in turn is actuated by the rotation of a gearchange barrel upon which is a cam profile. As the barrel is rotated the cam profile causes the correct selector fork to move at the correct time.
In operation of such a system, to effect a gearchange, one gear is de-selected, and then the subsequent gear selected. In order for the sliding ring system to engage and disengage with the gear the drive torque needs to be cut, this is typically done through the engine to gearbox clutch and/or an electronic engine cut. A cut in the engine torque for the required time to allow the gear to disengage results in the rate of vehicle acceleration being reduced. In certain applications, for example in motor sport, it is not desirable for the vehicle acceleration rate to reduce during a gear change.
A gearbox that allows a driver to make a gear change without the requirement to remove drive torque was disclosed by the present applicant in EP-A-1 736 678. Such a gearbox allows a driver to perform gear changes without interrupting drive power by arranging for drive hubs to be selectively connected to and disconnected from a drive gear in accordance with the rotational direction of torque between the hub and the gear: in other words, in accordance with whether the gear is tending to drive the hub or the gear is overrunning the hub.
SUMMARY
An aim of this invention is to improve the operation of the gearbox disclosed in EP-A-1 736 678.
To this end, from a first aspect, this invention provides a mainshaft for a gearbox assembly, the mainshaft assembly comprising:
a mainshaft; a first and a second drive gear, each carried for rotation about the mainshaft, each drive gear having a different number of teeth; a first and a second hub, each hub being associated with a respective drive gear, each hub having engagement means operable to selectively couple with the drive gear causing it to rotate with the hub or uncouple from the drive gear to allow the drive gear to rotate with respect to the hub; respective drive connection means associated with each hub being operative to connect the hub to the mainshaft for rotation with it or to allow rotation with respect to it, the connection means including connection elements having a deployed position in which they prevent relative movement between the hub and the mainshaft and a withdrawn position in which such relative movement is allowed; in which, upon connection of both first and second hub by their respective engagement means to each corresponding drive gear, the drive connection means operates to connect one of the hubs to the mainshaft when torque is applied to the mainshaft through the hub and to connect the other one of the hubs to the mainshaft when torque is applied to the hub through the mainshaft; wherein the drive connection means includes control means which, in an engaged condition, causes the connection elements to adopt their deployed position, and in a disengaged condition, allows the connection elements to be moved against a biasing force to their withdrawn position.
The presence of the biasing force ensures rapid engagement of the drive connection means when they are required to transmit drive.
Each connection element is typically a generally cylindrical pawl.
In a typical embodiment, in the withdrawn position, each connection element can be received within a respective recess in one of the mainshaft and the hub.
At least part of the biasing force may be provided by one or more springs within the hub. For example, each spring may be generally C-shaped and extend circumferentially partly around the mainshaft. Preferably, each spring is prevented from rotating about the mainshaft by one of the connection elements. Alternatively or additionally, at least part of biasing force may be provided by a helper assembly located within the mainshaft. The helper assembly may comprise a resiliently biased plunger that acts upon a pawl.
The control means may comprise a hollow cylindrical cage that surrounds the mainshaft and which extends between the hubs and the mainshaft. The cage typically includes slots within each of which a connection element is located. The cage may be formed of two coaxial components interconnected such that limited backlash movement can take place between them. In such embodiments, the slots may have a circumferential extent that is marginally greater than the diameter of the connection elements. Alternatively, the cage may formed of two coaxial components interconnected such that minimal backlash movement can take place between them or of a single coaxial component. In such embodiments, the slots may have a circumferential extent that is greater than the diameter of the connection elements to allow backlash movement between the cage and the connection elements.
Each engagement means typically includes a dog clutch that can engage with or disengage from dogs on a drive gear.
From a second embodiment, the invention provides a gearbox that includes a mainshaft assembly embodying the first aspect of the invention.
In such a gearbox, the drive gears of the mainshaft assembly may be in mesh with a respective laygear. The laygears are typically constrained to rotate together on a layshaft.
BRIEF DESCRIPTION OF DRAWINGS
Embodiments of the invention will now be described in detail, by way of example, and with reference to the accompanying drawings, in which:
FIG. 1 is a longitudinal cross-section of layshaft and mainshaft assemblies of a six-speed gearbox being a first embodiment of the invention;
FIG. 2 is an exploded view of the mainshaft assembly shown in FIG. 1 ;
FIG. 3 is an exploded view of a hub assembly shown in FIG. 2 ;
FIG. 4 is a section on B-B of FIG. 1 , showing the odd-speed hub of the first embodiment in a drive condition;
FIG. 5 is a section on C-C of FIG. 1 , showing the even-speed hub of the first embodiment in a ratchet condition;
FIGS. 6 and 7 show cage assemblies being two alternative components of the embodiment of FIG. 1 ;
FIG. 8 shows a helper assembly for use in embodiments of the invention; and
FIG. 9 shows the helper assembly of FIG. 8 installed in a mainshaft.
DETAILED DESCRIPTION
The embodiments described are five-speed or six-speed gearboxes intended for competition use. However, it will be seen that the principles of its construction could be extended in a straightforward manner to a gearbox having a smaller or larger number of speeds and different applications. The embodiments described may also provide some forward speeds in a gearbox in which further forward speeds are provided using conventional means.
With reference first to FIGS. 1 to 3 , the gearbox comprises two principal shaft assemblies—a mainshaft assembly 10 and a layshaft assembly 12 . Drive from the engine passes through the clutch and enters the gearbox to drive the layshaft assembly 12 . The output of the gearbox is taken from the mainshaft assembly 10 . Ratio selection is performed on the mainshaft and is controlled by a selector assembly.
The layshaft assembly 12 comprises six differently-sized forward-speed spur laygears 21 . . . 26 and a reverse spur laygear 27 carried upon a rotatable shaft 80 for rotation about an axis within the gearbox. The spur gears 21 . . . 27 and the layshaft 80 are coupled by splines so that they rotate together; that is to say, relative rotation between the spur gears is prevented.
The mainshaft assembly 10 has six forward-speed spur gears 31 . . . 36 each of which is in mesh with a respective spur laygear 21 . . . 26 of the layshaft assembly 12 , and a reverse-speed spur gear 37 that can be brought into mesh with the reverse spur laygear 27 through an idler gear (not shown) when reverse gear is selected. The sizes of the spur gears 31 . . . 37 are such that they are arranged along the straight axis of a mainshaft 44 that is parallel to the axis of the layshaft 80 . The mainshaft assembly is central to the operation of this embodiment, so it will now be described in detail with reference to FIGS. 2 and 3 .
The six forward-speed spur gears 31 . . . 36 of the mainshaft assembly provide 1 st to 6 th speeds, the six speeds being each incrementally higher in ratio than the previous gear, i.e., 6 th is higher than 5 th , and so forth. The gears are not arranged in ratio-order as is common in most gearboxes. Rather, they are arranged such that a first adjacent pair of gears 31 , 36 provide 1 st and 6 th gears, a second adjacent pair of gears (referred to as the even-speed pair) 32 , 34 provide 4 th and 2 nd gears respectively, while a third pair (referred to as the odd-speed pair) 33 , 35 provide 3 rd and 5 th gears respectively. The requirement in general is that adjacent speeds should not share a hub so that a speed change can be effected by changing which one of two hubs is transmitting drive to the mainshaft.
Note that, in this embodiment, the pair of gears 31 , 36 that provide the 1 st and 6 th speeds are connected to the mainshaft 44 using a conventional selector hub 38 , and do not make use of the change system provided by this invention; nor does the reverse gear 37 . Therefore, the following description will describe the operation of the odd-speed pair and the even-speed pair, which do benefit from the arrangement of the present invention.
Each spur gear 32 . . . 35 is supported on a respective bearing 40 , 40 ′ which in turn is mounted on a two-component cage 42 , 42 ′ that extends under all four gears. The cage 42 is carried on the rotatable mainshaft 44 . (The bearings 40 , 40 ′ could be bushes rather than rotating element bearings, as in this embodiment.) The components 42 , 42 ′ of the cage are carried on bearings 46 mounted on the mainshaft 44 such that they can rotate upon the mainshaft 44 . In alternative embodiments, bushes might replace the bearings, or the cage may be carried directly upon the mainshaft 44 .
Mounted on each component 42 , 42 ′ of the cage between the gears of the odd-speed pair and the even-speed pair, concentric to the mainshaft 44 , is a respective hub 50 , 50 ′. Mounted on each hub 50 , 50 ′ is a respective dog ring 54 , 54 ′ which, in this embodiment, is connected to the hub through a spline drive. Thus, the dog rings 54 , 54 ′ can slide axially with respective to the corresponding hub 50 , 50 ′, but cannot rotate with respect to it. Each dog ring 54 , 54 ′ can slide between three operative positions: a central neutral position in which it is spaced axially from both of the corresponding spur gears, or displaced from the central position in one or other direction to a respective drive position to engage one or other spur gear. When in a drive position, the dog ring 54 , 54 ′ engages with dog formations on the corresponding spur gear to lock that gear to the corresponding hub 50 , 50 ′ upon which it is carried such that the hub and the gear rotate together. This sliding movement is effected by selector forks of the selector assembly.
Each hub 50 , 50 ′ has a series of internal axially-aligned grooves 58 and is mounted on a respective component of the cage 42 , 42 ′. In this example, there are five such grooves, but other embodiments may have more or fewer. Each cage component 42 , 42 ′ has a series of rectangular slots 60 , each slot 60 being disposed approximately radially inwardly from a respective one of the grooves 58 . Likewise, the mainshaft 44 has a series of grooves 62 , each being disposed approximately radially inwardly from a respective one of the slots 60 . Thus, a space is enclosed between the internal grooves 58 of the hubs 50 , 50 ′, the slots 60 and the grooves 62 of the mainshaft 44 and located within each space is a respective pawl 64 , 66 of generally cylindrical outer shape.
The cage may be in several configurations, two of which are shown in FIGS. 6 and 7 respectively. Proximal end faces of the components 42 , 42 ′ of the cage have castellated formations at 74 that couple them together. In the first arrangement, shown in FIG. 6 , the slots 60 have a width just greater than the diameter of the pawls 64 , 66 . Thus, the pawls 64 , 66 are constrained to rotate about the mainshaft 44 along with the cage component 42 , 42 ′ in which they are located. The castellated formations 74 are configured to allow some limited rotational backlash movement between the components 42 , 42 ′ of the cage. In the second arrangement, shown in FIG. 7 , the slots 60 have a width somewhat greater than the diameter of the pawls 64 , 66 . Thus, the pawls 64 , 66 are caused to rotate about the mainshaft 44 along with the cage component 42 , 42 ′ in which they are located, with some backlash as the pawls 64 , 66 move from one side of their slots 60 to the other. The castellated formations 74 are configured to minimise rotational backlash movement between the components 42 , 42 ′ of the cage.
The grooves 58 of the hubs 50 , 50 ′ are curved such that each pawl 64 , 66 fits closely to the base of its groove 58 . The bases of the grooves 62 of the mainshaft 44 are also curved with a radius similar to that of the pawls 64 , 66 . However, each of the grooves 62 of the mainshaft 44 has sloping sidewalls upon which the pawls 64 , 66 can slide, thus allowing the pawls 64 , 66 a small amount of angular rotation around the mainshaft. The width of each slot 60 is slightly greater than the diameter of a pawl 64 , 66 . When a pawl is located in the base of its mainshaft groove 62 , its radially outermost extent does not project beyond the radially outer surface of the components 42 , 42 ′ of the cage.
Each pawl 64 , 66 is generally cylindrical, and has a transverse slot 90 , 92 formed in it. Two of the pawls 66 have a slot 90 that is of width approximately a quarter of the length of the pawl 66 , and offset such that one transverse edge of the slot 90 is approximately at the mid-point of the length of the pawl 66 . These are referred to as “anti-rotation pawls”. The remaining pawls 64 have a slot 92 that is of width approximately a half of the length of the pawl 64 , and is substantially mid-way along of the length of the pawl 64 . These are referred to as “locking pawls”. When assembled, the anti-rotation pawls 66 are separated from one another by at least one locking pawl 64 , and the slots 90 of the anti-rotation pawls are offset in axially opposite directions along the mainshaft 44 .
A pair of C-shaped springs 68 surrounds the mainshaft 44 . The natural diameter of the springs 68 is somewhat larger than that of the mainshaft 44 . When compressed to closely surround the mainshaft 44 , the free ends of the springs 68 are spaced from one another by a distance greater than the diameter of the pawls 64 , 66 . Both springs 68 pass within the slots 92 of all of the locking pawls 64 . However, the slots 90 of the anti-rotation pawls 66 are wide enough to receive just one spring 68 . Thus, each spring 68 passes through the slot 90 of one anti-rotation pawl 66 , and its free ends are disposed on opposite sides of the other anti-rotation pawl 66 . This prevents rotation of the springs 68 about the mainshaft 44 .
The slots 60 in the components 42 , 42 ′ of the cage are sized to allow the pawls 64 , 66 to disengage from the hubs 50 , 50 ′ as required during operation. The cage ensures that all of the pawls 64 under any one hub 50 , 50 ′ are aligned on the same side of the grooves 62 in the mainshaft 44 as required during operation of the system. The purpose of the pawls 64 , 66 is to allow the hubs 50 , 50 ′ to be coupled to or uncoupled from the mainshaft 44 , whereby when coupled, a hub 50 , 50 ′ is caused to rotate with the mainshaft 44 and when uncoupled can rotate with respect to it. The mechanism by which this occurs will now be described.
Consider first the state of the mainshaft assembly 10 as shown in FIG. 1 . Both dog rings 54 , 54 ′ are in their central positions, so all of the spur gears 31 . . . 36 are free to rotate with respect to the mainshaft 44 , and the cage components 42 , 42 ′ and pawls 64 , 66 are free. Thus, the gearbox is in neutral, no drive being transmitted from the layshaft assembly 12 to the mainshaft assembly 10 .
When driving in 4 th gear, the dog ring 54 ′ of the even-speed pair is located in its drive position with respect to the 4th spur gear 34 . Section B-B through 4th gear in FIG. 4 shows the drive where the torque is taken through the even-speed hub 50 ′ and the pawls 64 , 66 into the mainshaft 44 . The cage 42 is rotated fully in the direction of the drive torque by the pawls 64 , 66 .
If the vehicle is accelerating, it may be necessary to change up a gear, for example from 3 rd gear to 4 th gear. Initially, the 3 rd gear 33 will be engaged through the odd-speed hub 50 . To perform the gearchange, the 4 th spur gear 34 is engaged on drive by dog ring 54 ′ of the even-speed pair. Note that 3 rd gear 36 is also still engaged by the dog ring 54 of the odd-speed pair. Section B-B through the even speed hub 50 ′ shows that as the 4 th gear is engaged the drive torque is taken through the even-speed hub 50 ′ and pawls 64 , 66 to the mainshaft 44 . The pawls 64 , 66 have rotated the cage 42 , 42 ′ fully in the direction of the drive torque due to the drive torque. Section C-C in FIG. 5 through the odd-speed hub 50 shows that, due to the fact that the mainshaft 44 is now rotating faster than 3 rd gear (which is still engaged) the odd-speed hub 50 is now rotating slower than the even-speed hub 50 ′. As the cage 42 is forced fully in the direction of the drive torque by the even-speed hub 50 ′ and pawls 64 , 66 there is now sufficient space for the 3 rd gear pawls 64 , 66 to be forced into the grooves in the mainshaft 44 against the action of the springs 68 . This allows the odd-speed hub 50 to rotate slower than even-speed hub 50 ′ and therefore not transmit drive. Thus, 4 th gear has been engaged without the need to disengage 3 rd gear.
Once 4 th gear has been engaged, as described above, the dog ring 54 of the odd-speed pair is withdrawn from engagement with the 3 rd forward-speed spur gear 33 to its central neutral position. The even-speed hub dog ring 54 ′ remains in engagement with the 4 th spur gear 34 . The 3 rd spur gear 33 is now free to rotate on its bearing 40 as it is no longer joined to the odd-speed hub 50 by dog ring 54 —this is essential because there is no relative rotational motion between the odd-speed hub 52 and mainshaft 44 .
The sequence of operation to accomplish downchanges, with the example being from 4 th to 3 rd speeds, will now be described.
Before a downchange, engine torque is reduced such that it is now imposing a drag on the vehicle—that is, the direction of torque being transmitted by the gearbox is reversed. Once drive torque is removed, the even-speed hub will move rotationally in the opposite direction to the direction of rotation relative to the mainshaft 44 , and this will also rotate the pawls 64 , 66 in the same relative direction. The pawls 64 , 66 are urged radially outwardly by the springs 68 , ready to transmit drive. The coast torque is transmitted from the mainshaft 44 through the pawls 64 , 66 into the even-speed hub 50 ′ and thence to the even-speed dog ring 54 ′ and the 4 th speed spur gear 34 . The change in torque direction also forces the cage 42 to move to a coast position. The coast torque is now being taken by the slower gear, the torque path being from 3 rd gear 33 , through the odd-speed dog ring 54 , the odd-speed hub 50 and the pawls 64 , 66 into the mainshaft 44 . The pawls 64 , 66 are forced in the opposite direction to the direction of rotation by the odd-speed hub 50 . The cage 42 is already in the coast position because of the drive direction. The even-speed hub 50 ′ is rotating faster than the odd-speed hub 50 and therefore forces the pawls 64 , 66 into the grooves 62 in mainshaft 44 against the action of the springs 68 which allows the hub to rotate with respect to the mainshaft 44 , as shown in section C-C.
A helper assembly 70 that can be incorporated into the mainshaft 44 is shown in FIGS. 8 and 9 . This helper assembly 70 serves to apply a radial force to the pawls 64 , 66 additional to that of the springs 68 .
The helper assembly 70 comprises a tubular casing 72 that has an axial through bore and that is symmetrical about a centre plane normal to the axis. The bore has a central region of reduced diameter, and its end portions are internally threaded. The casing has an external diameter that is a close fit within the mainshaft 44 . A ball-spring plunger 92 is located centrally in the casing 72 , projecting radially outwardly from it. The ball-spring plunger cooperates with an internal groove of the mainshaft 44 to resist axial movement of the helper assembly 70 within the bore of the mainshaft 44 .
At positions that are radially inward of the pawls 64 , 66 when the helper assembly is installed for use, radial apertures 76 are formed through the casing 72 to communicate with the bore. A respective plunger 80 is located within each radial aperture 76 . Each plunger 80 has a tapered portion that is directed into the bore of the mainshaft 44 .
Each plunger 80 is acted upon by two expander elements 84 that are located to slide within the bore of the casing 72 . Each of the two expander elements 84 has a chamfered axial face that face one another and which bear upon the tapered portions of the plungers 80 . Each expander element 84 is acted upon by a pair of coaxial helical springs or a series of Belleville compression springs 86 , 88 , whereby the two expander elements 84 that are associated with each plunger 80 are urged towards one another. The compression springs 86 , 88 that are associated with the expander elements 84 closest to the centre plane of the casing 72 bear upon the central region of reduced diameter. The compression springs 86 , 88 that are associated with the expander elements 84 furthest from the centre plane of the casing 72 are retained by plugs 90 secured within the threaded end portions of the bore of the casing 72 . Alternatively, the bore might have a groove within which a circlip can be located to retain the springs. The action of the expander elements 84 acting on the plungers 80 causes the plungers 80 to be urged radially outwardly from the housing to bear upon the pawls 64 , 66 , thereby urging the pawls radially outwardly to supplement the action of the springs 68 . | A mainshaft assembly for a gearbox includes a mainshaft ( 44 ) and drive gears ( 31, 36 ) carried for rotation about the mainshaft. First and second hubs ( 50, 50 ′) are associated with respective drive gears, each hub being operable to selectively couple or uncouple with the drive gear causing it to rotate with the hub or with respect to the hub. A drive connection mechanism ( 42, 64, 66 ) associated with each hub selectively connects the hub to the mainshaft. Upon connection of the hubs to the drive gears, the drive connection operates to connect one or other of the hubs to the mainshaft when torque is applied to the mainshaft in a first direction or an opposite direction. This enables a gear ratio to be selected by reversing the torque being handled by the gearbox. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the field of power converters of switched-mode type. Such converters use an inductive element, associated with a power switch and with a free wheel diode, to perform a power conversion and a correction of the power factor, generally based on a D.C. input voltage. Voltage step-down converters (BUCK), voltage step-up converters (BOOST), and buck-boost converters are known.
The present invention more specifically relates to a circuit for helping the switching of the power switch of a switched-mode converter.
2. Discussion of the Related Art
FIG. 1 shows the simplified diagram of a conventional step-up converter 1 . Such a converter includes an inductance L 0 in series with a free wheel diode DL between two positive input and output terminals 2 and 3 of the converter, the cathode of diode DL being connected to terminal 3 . A power switch K connects the midpoint 4 of this series connection to a terminal 5 of application of a negative or reference voltage (generally, the ground) common to the converter input and output. A D.C. supply voltage source 6 provides a voltage V E across terminals 2 and 5 . On the output side, a storage capacitor C 0 generally connects terminals 3 and 5 and provides a voltage V S to a load Q. Load Q has been shown in FIG. 1 by dotted lines integrating capacitor C 0 , which may or not belong to the load. Switch K is controlled by a circuit 7 (CTRL), for example, in pulse-width modulation (PWM).
The operation of a step-up converter will now be described. When switch K is on, power is stored in inductance L 0 and load Q is supplied by the power stored in capacitor C 0 . When switch K is off, inductance L 0 gives back the stored power to capacitor C 0 via free wheel diode DL.
FIG. 2 shows the simplified electric diagram of a step-down converter 1 ′. It shows the same components as in FIG. 1 . However, here, switch K is connected in series with inductance L 0 between positive input and output terminals 2 and 3 . Free wheel diode DL grounds the junction point 4 ′ of switch K and inductance L 0 , its cathode being connected to point 4 ′. Switch K may also be provided between the negative terminal of source 6 and the anode of diode DL.
The operating principle is the same. Power is stored in inductance L 0 during the on periods of switch K. During periods when switch K is off, this power is given back to capacitor C 0 , free wheel diode DL being used to loop back the circuit.
A problem which arises with switched-mode converters, also called hard-switching converters, in which the current and the voltage cross each other upon each switching, is linked to the switch turning-on.
Indeed, upon each turning-on of switch K, free wheel diode DL must block. Now, at the blocking of a diode, especially of a PN junction diode, a recovered charge phenomenon occurs.
This phenomenon is illustrated by FIGS. 3A to 3C , which show, in relation with the circuit of FIG. 1 , an example of the shape of current I DL in the free wheel diode, of output voltage V S and of current I T in switch K.
Switch K is initially assumed to be off. Accordingly, a current I Lf flows through diode DL. This current corresponds to the power given back by inductance L 0 . The output voltage is at a level V 0 . As for switch K, the current I T flowing therethrough is null.
It is assumed that at a time t 1 , control circuit 7 turns switch K on. During the switching, current I L in the inductance, which corresponds to the sum of currents I DL and I T is a constant. Accordingly, the current which, during the switching, increases in the switch, translates as a decrease with an inverse slope of the current in diode DL.
At a time t 2 , the current in diode DL becomes zero and the current in the switch reaches level I Lf . At this time starts the recovered charge phenomenon of diode DL. This known phenomenon translates as an inversion of the current through the diode to reach a level I RM corresponding to the maximum recovery current of the diode. Current I RM is reached at a time t 3 from which the current through the diode tends towards zero again, reaching it at a time t 4 . Since the current in inductance L 0 is, during the switching, substantially constant, the negative current peak on the diode side translates as an overcurrent in switch K, the maximum value of which corresponds to current I Lf plus value I RM . On the side of voltage V S , the voltage decrease in practice intervenes from time t 3 , that is, from the inversion of the current slope in diode DL. In other words, the voltage across the diode is zero between times t 2 and t 3 corresponding to the first recovery phase ta. It can be considered that the diode then transiently conducts in reverse. Between times t 3 and t 4 (second recovery phase tb), voltage V S decreases from V 0 to a zero voltage. The voltage provided to capacitor C 0 is here considered. Indeed, the presence of the capacitor in practice results in output voltage V S remaining approximately stable.
The slope between times t 1 and t 3 of the current decrease in diode DL depends on the turn-on speed of the switch and thus on its di/dt at the turning-on. The higher this di/dt, which favors an abrupt switching, the higher amplitude I RM is for a PN-junction diode. However, the smaller di/dt, the longer the recovery time at the blocking (trr=t 4 −t 2 ).
The losses in a diode according to the di/dt value have a parabolic shape. There is an optimal point where the surface area of the current shape between times t 2 and t 4 is minimum, which results in minimum losses of recovered charges in the diode.
For switch K, the recovered charge phenomenon of the diode is particularly disturbing. Indeed, for a step-up converter, the switch then sees across its terminals, between times t 2 and t 3 , output voltage V S . In the case of a step-down converter, the voltage seen by the switch across its terminals corresponds to the voltage of generator 6 . In all cases, it is the highest voltage between voltages V E and V S .
High losses can then be observed in switch K. In FIGS. 3A to 3C , the loss periods have been symbolized by hatching on the various timing diagrams.
In practice, the losses in switch K (generally, a power transistor) at its turning-on (times t 1 to t 4 ) form most of the switching losses of the converter. In particular, the losses due to the actual blocking of the diode and the turn-off losses of the switch are negligible with respect to the losses generated at its turning-on.
A first solution to reduce this disadvantage consists of using diodes with no recovered charges, for example, Schottky or SIC-type diodes.
A first disadvantage of this solution is that diodes with no recovered charges are often limited to a breakdown voltage of some hundred volts. This solution is thus not applicable to converters operating under voltages of several hundreds of volts, which is in practice current in power electronics. Several diodes in series must then be provided to increase the breakdown voltage.
Another disadvantage of this solution is that, even if it decreases losses linked to recovered charges (times t 2 to t 4 ), the most significant losses linked to the sole switch turning-on are not avoided. Referring to the example of FIGS. 3A to 3C , the use of a diode with no recovered charges results in an zero voltage V S from time t 2 . There thus remain the losses linked to the surface areas located between times t 1 and t 2 .
Another disadvantage of diodes with no recovered charges is that they are particularly expensive as compared to PN diodes. Presently, the cost ratio is greater than 20.
A second solution to attempt solving recovered charge problems is to provide a circuit for helping the switching of the power switch of the converter.
FIG. 4 shows a conventional example of such an aid circuit, applied to a step-up converter such as shown in FIG. 1 . FIG. 4 shows all elements of FIG. 1 , to which is added a circuit 8 for helping the switching of switch K. This circuit is formed of an inductance L, associated in parallel with a resistor R and a diode D, between point 4 and switch K. The function of inductance L is to control the switch di/dt. By decreasing this di/dt value, amplitude I RM is decreased.
A problem which arises is that resistor R must be provided to dissipate a reverse overvoltage in inductance L. Indeed, upon the turn-on switching of switch K, the voltage across inductance L takes the value of output voltage V S . The same losses occur at the transistor turning-off. These are resistive losses which are all the greater as the di/dt value is high. In other conventional examples, dissipation element R is replaced with a capacitor, a zener diode, etc.
Thus, this second solution has the same disadvantages as the use of a diode with no recovered charges.
A third known solution (not shown) consists of a circuit for helping the switching using the transient switching resonance. Such a circuit uses, like the circuit of FIG. 4 , an additional inductance. However, to avoid resistive loss problems, a second switch, the control of which is desynchronized with respect to that of switch K, is used.
An example of a switching aid circuit of this type is described in paper “An overview of soft switching technics for PWM convertors” by G. Hua and F. Lee, published in EPE Journal, Vol. 3, March 1993.
Such a solution provides satisfactory results, but has a particularly complex and expensive implementation. In particular, a control system desynchronized from the used switches must be provided. Further, as compared to the circuit of FIG. 4 , it is necessary to have an additional power switch, two additional diodes and, above all, a high-voltage capacitor.
The present invention aims at overcoming the disadvantages of known switching aid circuits.
SUMMARY OF THE INVENTION
The present invention more specifically aims at providing a switching aid circuit which reduces losses due to the turning-on of a power switch.
The present invention also aims at providing a solution requiring no additional switch in a lightly dissipative circuit.
The present invention also aims at providing a particularly simple and inexpensive solution.
The present invention also aims at providing a solution which is compatible with the use of diodes with recovered charges (PN diodes).
The present invention also aims at preserving the control of the di/dt value upon turning-on of the power transistor.
To achieve these objects, the present invention provides a circuit for helping the switching of a switched-mode converter, which includes a first inductive power storage element in series with a free wheel diode and a switch, and a second inductive element for controlling the di/dt value upon turning-on of the switch, including:
a magnetic circuit having a main winding formed, at least partially, by the first inductive element;
means for discharging the second inductive element at the switch turning-off and turning-on; and
means for transferring the power corresponding to the turning-on to said main winding.
According to an embodiment of the present invention, said discharge means include:
a first circuit including a first switching diode; and
a second circuit including a first secondary winding of the magnetic circuit.
According to an embodiment of the present invention, said transfer means include the first secondary winding of the magnetic circuit and a second switching diode.
According to an embodiment of the present invention, the second discharge circuit includes the second inductive element in series with the first secondary winding, the second switching diode, and the switch.
According to an embodiment of the present invention, the switching aid circuit further includes a second secondary winding of the magnetic circuit in series with the free wheel diode.
According to an embodiment of the present invention, the secondary windings have a same number of turns.
According to an embodiment of the present invention, the number of turns of the main winding is greater than the numbers of turns of the secondary windings.
The present invention also provides a switched-mode converter of the type including a first inductive power storage element in series with a free wheel diode and a storage element of capacitive type, and a second inductive element for controlling the di/dt value upon turning-on of a switch for cutting-off a supply voltage, including a switching aid circuit.
According to an embodiment of the present invention, the converter is of voltage step-up type, the first inductive element forming the main winding of the magnetic circuit being in series with the second inductive element and the switch between two terminals of application of the supply voltage.
According to an embodiment of the present invention, the converter is of voltage step-down type, the switch being in series with, among other, the second inductive element and the free wheel diode, between two terminals of application of the supply voltage.
The foregoing objects, features and advantages of the present invention will be discussed in detail in the following non-limiting description of specific embodiments in connection with the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 , previously described, shows a conventional example of a voltage step-up switched-mode converter;
FIG. 2 , previously described, shows a conventional example of a voltage step-down switched-mode converter;
FIGS. 3A , 3 B, and 3 C, previously described, illustrate in the form of timing diagrams a problem posed by the circuits of FIGS. 1 and 2 ;
FIG. 4 , previously described, shows another conventional example of a voltage step-up switched-mode converter;
FIG. 5 shows an embodiment of a switching aid circuit according to the present invention applied to a voltage step-up converter;
FIGS. 6A , 6 B, 6 C, 6 D, 6 E, 6 F, and 6 G illustrate, in the form of timing diagrams, the operation of the circuit of FIG. 5 ;
FIGS. 7A , 7 B, 7 C, 7 D, 7 E, and 7 F show the equivalent electric diagrams of the circuit of FIG. 5 at the different switching phases; and
FIG. 8 shows a first embodiment of a switching aid circuit according to the present invention applied to a voltage step-down converter.
DETAILED DESCRIPTION
The same elements have been designated with the same references in the different drawings. For clarity, only those components which are necessary to the understanding of the present invention have been shown in the drawings and will be described hereafter. In particular, the structure of the power switch control circuit has not been detailed and is not part of the present invention, its implementation being within the abilities of those skilled in the art based on the functional indications given in the present description.
A feature of the present invention is to provide a magnetic circuit for organizing the discharge of an inductance for controlling the di/dt value, especially, upon closing of the power switch of a switched-mode converter.
Another feature of the present invention is to use this magnetic circuit to temporarily store the power generally lost upon switching of the power switch and for storing this power in the converter to the benefit of the load.
Another feature of the present invention is to use the inductive element of the circuit for correcting the power factor of the switched-mode converter as an element of the magnetic circuit.
FIG. 5 shows the electric diagram of a first embodiment of a voltage step-up switched-mode converter, equipped with a switching aid circuit according to the present invention.
As previously, power converter 10 includes a switch K controlled by a circuit (not shown), for example, a pulse-width modulation control circuit (PWM). A power storage inductance L 0 is connected, by a first terminal, to a positive terminal 2 of application of an input voltage V E provided by a source 6 (for example, a D.C. source). Switch K is in series with an inductance L for controlling the di/dt value, connected to the second terminal 4 of inductance L 0 . The other terminal of switch K is connected to a reference terminal 5 (generally, the ground). Conventionally still, a free wheel diode DL is placed between point 4 and a positive output terminal 3 of the converter. This positive terminal is connected to a first electrode of a storage capacitor C 0 (which may belong to the load Q to be supplied) across which is present output voltage V S . The other terminal of capacitor C 0 is grounded and the anode of diode DL is on the side of terminal 3 .
According to the present invention, inductance L 0 belongs to a magnetic circuit 11 , of which it forms the main winding. Magnetic circuit 11 includes two secondary windings L 1 and L 2 having respective numbers of spirals or turns N 1 and N 2 smaller than number N 0 of spirals of inductance L 0 . A first winding L 1 of magnetic circuit 11 is connected in series with diode DL across terminals 3 and 4 . In the example of FIG. 5 , this inductance has been shown between point 4 and the anode of diode DL. It may also be placed between the cathode of diode DL and terminal 3 , the anode of diode DL being then directly connected to point 4 . A second winding L 2 connects point 4 to terminal 5 by being associated in series with a diode D 2 , the anode of diode D 2 being directed towards ground 5 . As for inductance L 1 and diode D 1 , diode D 2 may be, conversely to what has been shown, connected to point 4 . Finally, a diode D 1 connects point 12 to terminal 3 between inductance L and switch K, the cathode of diode D 1 being connected to point 12 .
The function of winding L 1 is, upon turning-off of switch K, to impose a negative voltage across inductance L, to enable it transfer the power that it contains to capacitor C 0 . Diode D 1 is then forward biased.
Winding L 2 has the function, upon turning-on of switch K, of imposing a negative voltage across inductance L, to transfer the power that it contains into winding L 2 of the magnetic circuit. This power is recovered by winding L 0 which gives it back to capacitor C 0 at the next switch turning-off.
To respect these functionalities, the respective phase points of the windings are chosen as follows. Assuming that the phase point of winding L 0 is connected to terminal 2 as illustrated in FIG. 5 , the phase point of winding L 1 must be on the side of point 4 and the phase point of winding L 2 must be on the side of ground 5 . Conversely, if the phase point of winding L 0 is connected to point 4 , the phase point of winding L 1 must be on the side of terminal 3 and the phase point of winding L 2 must be on the side of point 4 .
The operation of the switching aid circuit shown in FIG. 5 will be described hereafter in relation with FIGS. 6A to 6G and 7 A to 7 F. FIGS. 6A to 6G show, in the form of timing diagrams with no scale consideration, an example of a switching cycle of switch K. FIGS. 7A to 7F show the equivalent electric diagrams of the circuit of FIG. 5 in the different switching phases.
FIG. 6A shows voltage V DL across free wheel diode DL. FIG. 6B shows current I DL in diode DL. FIG. 6C shows voltage V K across switch 4 . FIG. 6D shows current I K in the switch. FIG. 6E shows voltage V L across di/dt-control inductance L. FIG. 6F shows current I D1 in diode D 1 . FIG. 6G shows current I D2 in diode D 2 . The signs of the currents and voltages shown in FIGS. 6A to 6G are taken in relation with the directions indicated in FIG. 5 . In FIGS. 7A to 7F , the current flows have been symbolized by arrows.
It is assumed that before a time t 10 , switch K is off, the converter then being in free wheel (phase A). During this free wheel period, a current I 0 assumed to be constant flows through diode DL, being given back by inductances L 0 and L 1 . During this phase A where switch K is off, the equivalent diagram of the converter ( FIG. 7A ) only includes inductance L 0 in series with inductance L 1 and diode DL between terminals 2 and 3 to provide the power to the load and to capacitor C 0 . In FIG. 7A , forward-biased diode DL has been symbolized by a short-circuit. Voltage V DL across this diode is slightly positive and corresponds to the voltage drop in the forward PN junction (on the order of 0.7 V). Switch K sees across its terminals a voltage V 0 corresponding to voltage V S plus voltage V DL and decreased by the voltage drop in winding L 1 . Voltage V L in inductance L is indeed zero during this period, as will be seen hereafter in relation with the end of the timing diagrams. Diodes D 1 and D 2 are blocked and the currents flowing therethrough are accordingly null. Current I K in off switch K is of course null.
At time t 10 , the turning-on of switch K is controlled. This thus starts a turn-on beginning phase B, the equivalent diagram of which is shown in FIG. 7B . As compared to FIG. 7A , the only difference is that inductance L in series with on switch K (short-circuit) is interposed between point 4 and ground 5 . The di/dt value upon turning-on of switch K essentially depends on inductance L. Indeed, this di/dt value depends on voltage V S , on voltage V E , on the mutual inductance of the magnetic circuit and on the off-load inductances L 11 and L 22 of the transformer formed by primary winding L 0 , and secondary windings L 1 and L 2 . Due to the chosen spiral ratio, value L 11 is very large as compared to value L 22 . The mutual inductance is moreover small as compared to value L 11 . As a result, slope (di/dt) is, as a first approximation, equal to V S /L. Current I DL through diode DL thus decreases with this slope until a time t 12 . Since a PN junction is used, the diode exhibits a recovered charge area. Accordingly, current I DL annuls at a time t 11 , intermediary between times t 10 and t 12 . Time t 11 corresponds to the time when the current in switch K reaches value I 0 . Between times t 10 and t 12 , diodes D 1 and D 2 remain blocked. Voltage V L across inductance L becomes approximately equal to voltage V S .
At time t 12 , the current through diode DL reaches value I RM corresponding to the maximum recovered charges. From time t 12 , the charges recovered by diode DL decrease. Diode DL then behaves as a capacitor. The equivalent diagram of this operating phase C is shown in FIG. 7C where diode DL has been symbolized in the form of a capacitor. The rest of the elements are the same as in FIG. 7B . Since the number of spirals of inductance L 1 is small as compared to the number of spirals of inductance L 0 , voltage V L1 thereacross is small. As a result, the capacitance formed by diode DL charges negatively. This phenomenon is illustrated in FIG. 6B by a pursuit of the decrease of current I DL until a time t 13 in the form of a capacitor charge. The current decreases to a current I r conditioned by inductance L 2 . Indeed, voltage V L , which decreases during this phase C, becomes negative until diode D 2 is turned on when voltage V L becomes sufficiently negative (time t 13 ). As for diode DL, voltage V DL reaches, at time t 13 , value −(V S +V L1 +V L2 +V D2 ). Voltage V L reaches, at time t 13 , value −(V K +V L2 +V D2 ).
At time t 13 when diode D 2 turns on, current I DL through diode DL abruptly stops and the corresponding current is injected back into inductance L 2 . The excess current (I r ) gives the maximum amplitude of the current in inductance L 2 . This current depends on the numbers of spirals N 0 and N 2 of inductances L 0 and L 2 . From time t 13 , diode D 2 conducts (phase D). The equivalent diagram is illustrated in FIG. 7D . Since diode DL is blocked (non-conducting), capacitor C 0 is disconnected. The magnetic circuit is, during phase D, dissociated from load Q. Diode D 2 is then used as a free wheel element to transfer the power stored by inductance L into the magnetic circuit via winding L 2 . The voltages across diode DL and inductance L remain unchanged. Similarly, switch K being on, the voltage thereacross is zero. Diode D 1 is blocked. When the current is entirely transferred into the magnetic circuit by inductance L 2 , the current therein goes to zero (time t 14 ), which causes a natural blocking of diode D 2 , that is, with a small di/dt. Winding L 2 enables decreasing of the current in switch K by transferring the power to the magnetic circuit which will give it back through inductance L 0 . Between times t 13 and t 14 , the current in switch K will decrease from level I 0 +I r to level I 0 .
At time t 14 , the voltage across inductance L goes to zero, all the power that it contained having been transferred to the magnetic circuit. The voltage across diode DL slightly rises back while remaining negative and takes a value −(V S +V L1 )+V L +V K . It should be reminded that voltages V L and V K are negligible (considered as null) with respect to voltages V S and V L1 .
Time t 14 is the beginning of a phase E where the switch is on and where the switching is over. The equivalent diagram is shown in FIG. 7E . It only includes source 6 , inductances L 0 and L, and switch K. Current I K is stable at level I 0 , as well as voltage V DL , the free wheel diode being blocked. The voltage across switch K of course is zero, as well as the voltage across inductance L and the currents in diodes D 1 and D 2 . During phase E, inductance L 0 is loaded through inductance L and switch K.
At a time t 15 when switch K is turned off, a negative voltage is imposed across inductance L, due to the presence of winding L 1 . It should be noted that, in this case, it is not necessary to control the di/dt value upon turning-off of the transistor (conventionally). The current abruptly stops in switch K. The inversion of the voltage across inductance L 1 causes the discharge, through diode D 1 , of the power stored during phase E in inductance L. At time t 15 , current I D1 thus abruptly takes value I 0 and this current decreases to reach value zero at a time t 16 . The decrease slope of current I D1 is a function of the value of inductance L and approximately corresponds to V L1 /L. The current through inductance L goes to zero at time t 16 and all the current accumulated in winding L 0 then flows through winding L 1 and diode DL. The equivalent diagram of phase F is illustrated in FIG. 7F . It should be noted that diodes DL and D 1 are on at the same time, but the current through diode DL starts from zero at time t 15 .
Time t 16 starts a new phase A where the switch is off.
An advantage of the present invention is that it enables recovering the losses due to the turn-on switching of the power switch to inject them back into the load by means of the magnetic circuit. The reinjection of the current into the converter, during turn-on switching phase D of the switch, enables decreasing the duty cycle. The controller (control circuit of switch K) generally automatically decreases this duty cycle by a regulation means which is not part of the present invention. A significant improvement of the converter efficiency is thus here obtained.
Another advantage of the present invention is that the provided solution is particularly simple. As compared to the conventional circuit of FIG. 4 , one power switch and, above all, a complex control circuit, are spared.
Another advantage of the present invention is that it requires no modification of the power switch control circuit, provided that said circuit performs (which is generally the case) a regulation. The implementation of the present invention requires adding one magnetic circuit L 0 , L 1 , L 2 , which can be obtained by means of a single three-winding inductance. Such a magnetic circuit is considerably less expensive than the required complexity of the control circuit of FIG. 4 and than a diode with no recovered charges. On this regard, it should be noted that the solution of a diode with no recovered charges does not enable recovering the losses in the switch.
FIG. 8 shows another embodiment of a switching aid circuit 10 ′ of the present invention, applied to a voltage step-down converter. The diagram of FIG. 8 should be compared to that of FIG. 2 . As compared to the diagram of FIG. 2 , inductance L is interposed between point 4 ′ and switch K. Inductance L 2 in series with diode D 2 is connected between terminal 2 and point 4 ′, the anode of diode D 2 being on the side of terminal 2 . Winding L 1 is connected in series with diode DL between point 4 ′ and ground 5 , the anode of diode DL being on the ground side. Finally, diode D 1 connects to ground 5 point 12 between switch K and inductance L, the anode of diode D 1 being grounded. In the example of FIG. 8 , the phase point of winding L 0 is connected to point 4 ′. Accordingly, to fulfill the described functions of magnetic circuit 11 ′, the phase point of winding L 1 is on the side of ground terminal 5 and the phase point of winding L 2 is on the side of terminal 2 .
The operation of the switching aid circuit illustrated in FIG. 8 can be deduced from the discussion of FIGS. 5 to 7 .
Of course, the present invention is likely to have various alterations, modifications, and improvements which will readily occur to those skilled in the art. In particular, the sizing of the different windings of the magnetic circuit may be modified, provided to respect a winding L 0 having a number of spirals much greater than windings L 1 and L 2 . Preferably, the numbers of spirals of windings L 1 and L 2 are equal, and the number of spirals of winding L 0 is approximately 10 times greater than that of windings N 1 and N 2 .
Further, adapting the present invention to a buck-boost converter is within the abilities of those skilled in the art based on the indications given hereabove.
Further, the present invention applies to any converter assembly, provided that it is a switched-mode converter. In particular, if in the case of a step-down converter ( FIG. 8 ), the switch has been shown with a terminal connected to the most positive voltage, there also exist assemblies in which this switch has a grounded terminal. The present invention also applies to this type of assembly. It is sufficient to invert the respective positions of series associations K–L and L 1 –DL with respect to point 4 ′, to connect diode D 1 by its cathode to terminal 2 , and to place series association L 2 –D 2 in parallel on association K–L, the cathode of diode D 2 remaining connected to node 4 ′. Inductance L 0 still is connected on the cathode side of free wheel diode DL in series with capacitor C 0 .
Finally, among the possible alternatives, inductance L 0 may be divided into a (main) element of the magnetic circuit in series with a distinct inductance that does not belong to the magnetic circuit. The switching speeds of the diodes may also be adapted although, to obtain the advantages of the present invention, these diodes need not be fast.
Having thus described at least one illustrative embodiment of the invention, various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be within and scope of the invention. Accordingly, the foregoing description is by way of example only and is not as limiting. The invention is limited only as defined in the following claims and the equivalents thereto. | The invention relates to an auxiliary switching circuit ( 10 ) for a chopping converter comprising a first inductive element (L 0 ) for serial energy storage with a free-wheel diode (DL) and a switch (K), in addition to a second inductive element (L) for di/dt control when the switch is closed, the auxialiary switching circuit comprising a magnetic circuit ( 11 ) whereby a main winding thereof is formed at least partially by the first inductive element (L 0 ), also comprising means (L 1 , D 1 , L 2 , D 2 ) for discharging the second inductive element when the switch is opened or closed, and means (L 2 , D 2 ) for transferring the energy corresponding to the closure vis a vis said main winding. | 7 |
BACKGROUND OF THE INVENTION
The invention relates to the field of carton forming, and more particularly to apparatus for forming and adhesively bonding a carton formed from a coated paperboard blank.
Many types of cartons formed from folded paperboard or the like have been developed over the years. These cartons fall into two major groups, namely cartons which use interlocking corners and tabs to secure the carton in the erected position, and cartons which have an adhesive coating applied to selected portions of the paperboard blank. The latter cartons when erected, are secured in their erected position by the adhesive bond which forms between the panels.
Carton blanks which are to be adhesively bonded generally include at least a base panel, wall panels attached to the base panel, and gussets or panels formed at the corners of the wall panels. Adhesive is coated on the corner panels, or alternatively on portions of the wall panels adjacent the corner panels, and the carton walls and corner panels erected and folded into contact with one another and secured together for a time sufficient to allow the adhesive to set.
Prior art machines for performing such carton forming and gluing operations are exemplified by the patent to Hoyrup, U.S. Pat. No. 3,626,819 issued on Dec. 14, 1971 and assigned to the assignee of the present invention. This patent shows a vertically reciprocating plunger disposed above a carton forming die. A movable carrier having a suction cup transfers the carton blank from a stack into contacting registration with the upper surface of the carton forming die. The die includes a number of vertical posts for controllably erecting and folding wall panels of a carton blank disposed over the die when the carton blank is forced therein by the motion of the plunger. Spots or strips of adhesive are applied to the under surface of the blank at the die mouth by a daubing applicator which rises from a pool of adhesive disposed next to the die. One disadvantage of this prior art type of apparatus is that when a number of spots of adhesive must be applied to a carton blank, such as a clam-shell type blank, the large number of adhesive applicators and associated mechanisms which would be required would interfere with the carton folding process. Also, the daubers are known to have to be cleaned frequently and this adds to the overall costs of the packaging operation.
An alternative method of coating portions of a carton blank with adhesive involves the use of a spring-biased ball dispenser attached to a pivoting arm mounted adjacent the forming head, as shown in the patent to Zanetti, U.S. Pat. No. 1,965,274, issued on June 2, 1917. Adhesive applicators have also been placed on a separate glueing frame which swings across the carton blank before die forming, as shown in U.S. Pat. Application Ser. No. 3,854,385, issued on Nov. 14, 1961.
Finally, the patent to Mosse, U.S. Pat. No. 3,008,386, shows a moving carrier for transferring a carton blank from a stack into registration over a carton forming die in which the carrier includes a resistance heater for activating a thermoplastic adhesive coating applied to portions of the blank.
In order to increase the "throughput", or number of cartons which can be formed and glued within a given amount of time, it would be desirable to provide carton forming apparatus of the type described with some means for accurately and economically applying adhesive to a carton blank which would not interfere in any way with the carton forming apparatus itself. It is desirable to have such adhesive application means light in weight and relatively simple and inexpensive to construct and maintain. It is also desirable that such adhesive application means include some means to prevent application of adhesive when a carton blank is not registered over the mouth of the carton forming die.
It is therefore an object of the invention to provide apparatus for rapidly forming an adhesive bonded carton having improved adhesive application means.
It is another object to provide apparatus for rapidly forming an adhesive bonded carton having adhesive application means attached directly to the carton blank transfer frame.
It is a further object to provide apparatus for rapidly forming an adhesive bonded carton having means for securing the adhesively bonded joints of a carton after forming.
It is yet a further object to provide apparatus for rapidly forming an adhesive bonded carton including means for preventing actuation of the adhesive applicator means when no carton blank is attached to the carton blank transfer frame.
These and other objects are achieved by the present invention wherein there is provided improved apparatus for adhesively bonding a carton. The paperboard clam-shell blank from which the carton is formed includes at least a base panel, wall panels attached to the base panel, and corner panels formed at the corners of the wall panels. The apparatus includes a carton forming die for receiving a paperboard blank, a reciprocating plunger mounted above the die for forcing the carton blank into the die to erect and form the carton, a movable frame having one or more vacuum assisted suction cups mounted thereto for lifting a carton blank from a stack, and means for moving the frame to transfer the carton blank held by the suction cups from the stack into registration over the forming die and for pressing the carton blank into contact with the die. The adhesive applying means includes one or more spring-loaded adhesive applicators connected to a pressurized source of liquid adhesive for applying adhesive to a selected portion of the carton blank when the carton blank is pressed into contacting registration with the die. A stacking cage disposed beneath the carton forming die receives and retains the erected and formed carton in a vertically stacked, nested arrangement, whereby the adhesive coated corners of the carton are retained in contact with adjacent carton wall panels by the pressure applied from the previous nested carton, for a time sufficient to allow an adhesive bond to form therebetween.
The spring-loaded adhesive applicator of the invention, includes a hollow cylindrical feed tube connected to a source of pressurized liquid adhesive, a constricted opening formed in the feed tube, and a spring-biased ball valve disposed in the constricted feed tube opening. When the carton blank, carried by the movable frame, is pressed into contacting registration with the forming die, the spring biased ball valve is displaced by contact with the carton blank and pressurized adhesive flows therethrough onto the carton blank. Openings formed on the surface of the die cooperate with the adhesive applicators when no carton blank is secured to the movable transfer frame. As will be understood more fully below, the carton blank forms a bridge over the openings in order to lift the ball in the valve off the seat thereby providing the desired controlled spot of adhesive.
The adhesive applicators of the present invention are small in size and light in weight, permitting a number of such applicators to be mounted on the carton blank transfer frame without unduly burdening the frame with excessive weight that would otherwise limit speed. These small size applicators can be used in the limited space available on the transfer frames in modern carton folding apparatus with a minimum amount of modification.
The spring-loaded applicators are self-opening when contacting the carton, thus eliminating the need for complex and heavy solenoid or air-actuated adhesive valves. The adhesive applicators accurately dispense the proper amount of liquid adhesive to selected areas of the carton blank with little or no wastage or spilling of adhesive.
The adhesively coated carton is rapidly set up by the reciprocating plunger of the apparatus of the present invention which forces the carton through the die to erect the carton walls and fold the corner panels of the carton into contact with adhesive coated portions of adjacent carton walls. When the reciprocating plunger reaches its lowest point of harmonic motion with respect to the forming die, the erected carton is ejected from the lower portion of the forming die into a stacking cage which retains the cartons in a stacked arrangement. The cartons are nested one above the other to secure the adhesive coated portions of the wall panels against the corner panels for a time sufficient to allow an adhesive bond to form therebetween. Since the adhesive sets while the erected carton is securely retained in the stacking cage by the pressure applied from neighboring nested cartons, the throughput of the carton forming apparatus is independent of the adhesive setting time. Thus, the number of cartons which can be set up and bonded within a given period of time depends mainly on how quickly a carton blank can be fed into the registration with the die and then forced therethrough by the reciprocating plunger.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
These and other objects and features of the present invention are presented in the following detailed description taken in conjunction with the accompanying drawing figures, wherein:
FIG. 1 is a plan view of a preferred type of clam-shell carton blank for use with the apparatus of the present invention;
FIG. 2 is a perspective view of the carton blank of FIG. 1 showing it in its folded and erected position;
FIG. 3 is a perspective view of the carton of FIG. 2 showing it in its final, assembled and closed position;
FIG. 4 is a right side cross-sectional view of a preferred apparatus for forming the carton of FIGS. 1 through 3;
FIG. 5 is a top view of a carton blank transfer frame shown in its unactuated position holding a carton blank;
FIG. 6 shows the carton blank transfer frame of FIG. 5 in its actuated position for initiating the folding of the articulated hinge of the clam-shell carton of FIG. 1;
FIG. 7 is a cross sectional view of the transfer frame of FIG. 5 taken along lines 7--7;
FIG. 8 is a cross sectional view of the carton blank transfer frame of FIG. 6 taken along lines 8--8;
FIG. 9 is a detailed cross-sectional view of the spring-loaded adhesive applicators which are mounted to the carton blank carrier frame shown in FIG. 8 taken along lines 9--9;
FIG. 10 is a top view of the carton forming die shown in FIG. 4, illustrating the arrangement of the die, corner panel folding posts, and carton blank in its initial position; and
FIG. 11 shows the carton blank of FIG. 10 as it is being progressively folded and erected in the carton forming die.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred form of a carton blank for use with the apparatus of the present invention is shown in FIG. 1 and includes a lefthand base panel 3, and a righthand base panel 5 connected to base panel 3 by a "living" (articulated) hinge 7. Hinge 7 is formed by lefthand hinge panel 9 and righthand hinge panel 11, which are respectively connected to base panels 3 and 5. Hinge panels 9 and 11 each include a pair of tabs 13 formed on opposite ends thereof. A pair of side wall panels 15 are attached to opposite sides of base panel 3. An end wall panel 17 is also attached to the remaining side of base panel 3. A locking flap 19, including a locking slit 21, is formed on the outer portion of wall panel 17. A pair of folding corner panels 23 are formed between left side wall panels 15 and left end panels 17.
Similarly, a pair of wall panels 25 are attached to righthand base panel 5. A righthand end panel 27 is also attached to the remaining side of righthand base panel 5 and includes a locking tongue 29 which is adapted to fit into locking slit 21 when the carton blank is erected as shown in FIG. 3. A pair of folding corner panels 31 are formed between righthand wall panels 25 and righthand end panel 27. Corner panels 23 and 31 are separated from their respective adjacent wall panels 15 and 25 by a cut or slit, shown in solid lines in FIG. 1. The dashed lines in FIG. 1 indicate prescored areas of the carton blank adapted to be folded.
It will be appreciated that a number of folding and gluing operations must be performed in order to form the paperboard blank of FIG. 1 into the completed, clam shell type carton shown in FIG. 2. The line between hinge panels 9 and 11 of hinge 7 must be properly prebroken and then folded, glue applied to areas of wall panels 15 and 25 adjacent tabs 13 and corner panels 23 and 31, and then the side and end walls of the carton folded and erected into the position shown in FIG. 2. Contact between tabs 13 and corner panels 23 and 31 and the bonded areas on the carton side walls must be maintained for a time sufficient to allow an adhesive bond to form therebetween. Because adhesive must be applied to at least eight areas of carton 1, it is desirable for the carton forming apparatus to include relatively simple means for precisely applying the adhesive to selected areas of the carton. Of primary importance is to insure that the operation does not substantially interfere with the speed of operation of the carton forming apparatus. To this end the carton forming apparatus of the present invention includes a paperboard blank carrier frame 33 to which is mounted a number of spring-loaded adhesive applicator assemblies 35 for applying a liquid adhesive under pressure to selected areas of the carton blanks as shown in FIG. 4 in conjunction with FIGS. 7-9, and will be described in detail below.
The carton forming apparatus shown in FIGS. 4 through 11 includes a vertically reciprocating plunger 37, a carton forming head or die assembly 39 disposed directly beneath plunger 37 for receiving a carton blank, such as shown in FIG. 1, and a stacking cage 41 disposed beneath die 39. The cage 41 comprises a number of vertically disposed rails for receiving and retaining the carton blanks after they are erected.
Carton blanks to be folded and erected are sequentially transferred from a stack of carton blanks 43 by means of one or more vacuum assisted suction cups 45 connected to the underside of carton blank carrier frame 33. A source of negative air pressure V (FIG. 7) is connected to suction cups 45 to pick up a carton blank from stack 43 (FIG. 4). Carton blank carrier frame 33 is mounted to a drive (not shown) for movement about an axis to transfer a single carton blank from stack 43, as shown by solid lines in FIG. 4, into registration directly over forming die assembly 39, as shown by broken lines in FIG. 4. Movable carton blank carrier frame 33 is then moved downwardly toward the upper face of die assembly 39.
As shown clearly in FIG. 7, the carton blank carrier frame 33 includes a number of spring-loaded control plungers 47 designed to prevent the surface of the carton blank from applying unwanted pressure to spring-loaded adhesive applicators 35 before the die 39 is engaged. Also, spring-loaded plungers 47 cause carton blank 1 to be held in a slightly bowed position with respect to frame 33. Plungers 47 prevent carton blank 1 from contacting the tips of adhesive applicators 35 until the carrier frame and carton blank are fully registered into contact with the upper surface of forming die 39, as shown in FIG. 8. As frame 33 approaches the upper surface of forming die assembly 39, a pair of hinge folding blades 49 are pivoted into the position shown by solid lines in FIG. 4. Openings are formed in the side walls of die assembly 39 to allow for the pivoting motion of blades 49.
Just prior to the point at which carton blank 1 is fully registered in contact with the surface of carton forming die 39 (FIG. 8), hinge 7 of carton blank 1 contacts the upper edge of hinge prebreaking blades 49. The continued downward motion of the frame carrier carton blank 1 causes hinge portion 7 of blank 1 to be folded into an inverted V-shape as shown in FIG. 8.
As carton blank 1 is pressed into contact with the upper surface of forming die 39, as shown in FIG. 8, corner panels 25 and 31 of carton blank 1 are urged upwardly through contact with respective left and right hand erecting posts 55 and 57. Hinge 7 of carton blank 1 is formed through the downward motion of transfer frame 33 which forces hinge area 7 against blades 49. As a result, the outer edges of end panels 17 and 27 of carton blank 1 are drawn into engagement with respective left and right hand carton registration posts 69 and 61. Registration posts 59 and 61 include threaded portions formed thereon which engage the outer edges of carton blank end panels 17 and 27 to prevent misalignment or dislocation of the carton blank after carrier frame 33 is removed from contact therewith.
Nearly simultaneously with the contacting engagement of carton blank 1 with the upper surface of forming die 39, respective left and right hand bumpers 67 and 69 causing the spring-loaded suction cups 45 carried on spring-biased pivoting activator arms 63 and 65, to be disengaged from contact with the surface of tray blank 1, as shown in FIG. 8. At this time the spring-loaded adhesive applicators 35 contact the surface of carton blank 1 and are activated.
As shown clearly in FIG. 9, each adhesive applicator 35 comprises a hollow cylindrical feed tube 71 having a constricted opening or seat 73 formed at one end thereof. Each adhesive applicator 35 further includes a ball valve comprising a circular ball 75 biased by a spring 77 on the seat 73 to keep the applicator normally closed. Feed tube 71 of adhesive applicator 35 is connected to a manifold 70 which in turn is connected through a hose 81 to source of adhesive 83. The adhesive contained in pressurized adhesive source 83 preferably is a liquid adhesive, such as polyvinyl acetate. Thus, the downward motion of adhesive applicators 35, attached to movable carrier frame 33, causes ball 75 of applicators 35 to contact the upper surface of carton blank 1 and displace ball 75 upwardly to open the ball valve. The adhesive under pressure flows through tube 71 and nozzle 73 of applicator 35 to apply the adhesive to a selected area of carton blank 1 (shown as spots 87 in FIG. 10) directly below each applicator 35.
As mentioned above, the apertures 85, disposed beneath each applicator 35, are formed in the upper surface of die 39 adjacent the mouth of the die. In the event that no carton blank 1 is secured to carrier frame 33, or if a carton blank is improperly registered on top of die 39, applicators 35 are received within apertures 85 to prevent the actuation of the adhesive applicator ball valve. Alternatively, an apertured backup plate can be placed directly over the upper surface of die 39 to serve the same purpose. In either case, accidental or unwanted actuation of adhesive applicators 35 is prevented without the need for complicated carton registration sensing apparatus, as is common in the prior art. This technique for preventing unwanted actuation of adhesive applicators 35 constitutes an important feature of the present invention.
After adhesive has been applied to carton blank 1, the motion of movable frame 33 is reversed, drawing the frame upwardly away from die 39. Ball valves of adhesive applicators 35 automatically close and the movable frame 33 is pivoted into position (as shown in solid lines in FIG. 4) to pick up and transfer the next carton blank in stack 43.
In FIG. 10, carton blank 1 is shown aligned in full contacting registration with the upper surface of die 39 and subsequent to the application of adhesive to selected areas 87 of the carton blank and removal of carrier frame 33. Side wall panels 15 and 25 of carton 1 are secured in a relatively horizontal position over die 39 by T-bar retaining devices 89 and 91.
Once the blank is in the operative position with adhesive applied, as just described, blades 49 are pivoted downwardly into a standby position, shown by dashed lines in FIG. 4. Reciprocating plunger 37 is then actuated to move downwardly into contact with the upper surface of carton blank 1 disposed over die 39. The downward motion of plunger 37 forces carton blank 1 into the mouth of die 39 with corner panels 23 and 31 being fully folded and erected through contact with posts 55 and 57. As carton blank 1 is further urged into die 39, side and end panels 15, 25, 17 and 27 are erected. When carton 1 is fully erected, carton panels 23 and 31 and hinge tabs 13 are disposed adjacent to and in contact with the previously applied spots of adhesive 87 as shown in FIG. 11 (with plunger 37 removed for clarity).
When plunger 37 reaches its lowest point of reciprocating harmonic motion with respect to die 39, the erected carton is ejected into a stacking cage 41, as shown in FIG. 4. Stacking cage 41 comprises a number of vertically disposed guide rails. Stacking cage 41 receives and retains the erected cartons in a nested fashion, one within the other. The exterior of a nested carton is in intimate contact with the interior of its next lower carton. This arrangement causes corner panels 23, 31 and tabs 13 to be securely held against glued areas 87 of wall panels 15 and 25 while the adhesive sets. Thus, the nested stacked arrangement of cartons 1 in stacking cage 41 allows the glued joints of carton 1 to be secured for a time sufficient to allow the adhesive to set without hindering the operating speed of the reciprocating plunger and carrier frame assembly. An important advantage of this arrangement is that the "throughput" or number of cartons which can be formed in a given amount of time by the present invention is independent of the adhesive setting time. In addition, no auxiliary apparatus is needed to clamp or hold the glued joints of the cartons since the stacking cage performs this function.
Cartons 1 are reasily removed from the bottom of stacking cage 41 one by one or as needed.
It can thus be seen that the present invention has many advantages over prior art adhesive bonding apparatus for cartons. The adhesive applicators of the present invention are small in size and light in weight which allow their use directly on a movable carton blank carrier frame. The small size of the adhesive applicators allows their use within the confined areas present on modern day carton forming apparatus. The spring-loaded ball valve of the adhesive applicators enables a precise quantity of liquid adhesive to be applied to selected areas of a carton blank without wastage or spillage of the adhesive.
The adhesive applicators of the present invention are useful for applying adhesive to a wide variety of paperboard blanks. Any number of the adhesive applicators can be arranged about a carton blank carrier frame to accommodate different size cartons or particular gluing needs. The apertures formed around the periphery of the forming die advantageously prevent accidental or unwanted actuation of the adhesive applicators in the event that a carton blank has not been picked up by carrier 33 or if the carton blank is misregistered over the forming die. The nested stacking arrangement of the cartons in the stacking cage of the present invention allows the glued joints of the formed and erected carton to be securely held by the pressure of adjacent cartons for a time sufficient to allow the glued joints to set, thus dispensing with the need for auxiliary clamping apparatus which might interfere with the carton folding process.
While the adhesive bonding apparatus of the present invention has been described in considerable detail, it is understood that various changes and modifications may occur to persons of ordinary skill in the art without departing from the spirit and scope of the appended claims. | Apparatus for adhesively bonding a clam-shell type carton formed from a paperboard blank includes a carton forming die for receiving the paperboard blank, a movable frame for transferring the carton blank from a stack into registration over the die and a reciprocating plunger mounted above the die for forcing the carton blank into the die to fold and erect the carton. The movable frame includes a number of vacuum assisted suction cups for lifting the carton blank from the stack and a plurality of spring-loaded adhesive applicators, connected to a pressurized source of adhesive, for applying a spot of adhesive to selected portions of the carton blank when the blank, carried by the movable frame, is pressed into registration over the forming die. A stacking cage is disposed beneath the carton forming die to receive and retain the erected and folded cartons in a vertically stacked, nested arrangement, with adjacent cartons bearing against one another so that the adhesive coated portions of each nested carton are retained in contact with adjacent panels of the carton for a time sufficient to allow an adhesive bond to form therebetween. | 1 |
FIELD OF THE INVENTION
THIS INVENTION relates to signalling devices and in particular to a signalling device which can be used underwater to signal to and between divers.
BACKGROUND TO INVENTION
Various means have been devised by which acoustic signals may be generated underwater. Generally these comprise pistons impacting against a diaphragm in contact with water. U.S. Pat. Specification No. 4,095,667 to Mahig and Allen describes a portable underwater signalling device. Other acoustic signal generators are described in U.S. specifications 3,433,202 to Sharp et al and 3,277,437 to Bouyoucos.
In Mahig and Allen, U.S. Pat. No. 4,095,667, the valving to drive the piston and the piston involve complex shapes and sealing arrangements.
In Sharp, U.S. Pat. No. 3,433,202, and Bouycousos, U.S. Pat. No. 3,277,437, valving is achieved externally of the device such that these devices are not useful to divers needing a small hand held acoustic generator.
OBJECT OF THE INVENTION
It is an object of the invention to provide a signalling device by which communication between divers is possible with an acoustic generator of simple construction which is able to be hand held or incorporated into other equipment such as buoyancy control devices and which is a unit requiring only a high pressure air line connected thereto.
The invention achieves its object in providing a signalling device for underwater use comprising:
a main body part having a bore therein to form a cylinder with at least one open end thereto;
a diaphragm fitted to the main body part over the at least one open end of the cylinder, the diaphragm being, in use, in contact with water;
a piston contained within the cylinder, for movement to and fro therein;
an inlet to the cylinder on the main body part whereat a pressurised gas may be supplied; and
a valve means mounted in the main body part between the inlet and the cylinder; and
the valve means, in use, switching pressurised gas to opposite ends of the piston to repetitively drive the piston against the diaphragm.
In a particular form of the invention there is provided a pneumatic signalling device for hand held use by divers when underwater, said signalling device comprising:
a main body part having a bore therein to form a cylinder with an open end thereto;
a diaphragm fitted to the main body part over the open end of the cylinder, the diaphragm being, in use, in contact with the water;
a piston with first and second pressure faces at opposite ends thereto contained within the cylinder for movement to and fro therein, to impact the end associated with the first pressure face against the diaphragm;
an inlet to the cylinder on the main body part whereat an air line may be attached to feed air under pressure to a flapper valve; and
a flapper valve mounted in the main body part between the inlet and the cylinder;
action of the flapper valve under pressure of air serving to switch pressurised air repetitively to first the second pressure face and then the first pressure face to drive the piston to and from the diaphragm to repeatedly impact thereagainst and generate, in use, an acoustic signal in the water.
In this specification the terms bistable and flapper valve are to include any valve suitable to switching an inlet to either of two outlets, the state of the valve being switchable to either of the two outlets by any suitable means.
BRIEF DESCRIPTION OF DRAWINGS
The invention will now be described with reference to a preferred embodiment as shown in the accompanying drawings in which:
FIG. 1 is an exploded view of the main body part or cylinder, end cap, locking ring and diaphragm of a signalling device in accordance with the present invention;
FIG. 2 is a view of the end plug at the inlet end of the signalling device as seen in FIG. 1;
FIG. 3 is a view of the cylinder of FIG. 1 looking at the inlet end;
FIG. 4 is a view of the cylinder of FIG. 1 looking at the diaphragm end;
FIG. 5 is a sectional view through the parts of a valve which may be employed in the signalling device of FIGS. 1 to 4;
FIG. 6 is a view of a piston which may be employed in the signalling device of FIGS. 1 to 4;
FIG. 7 is a schematic drawing setting out the internal geometry of an alternate signalling device in accordance with the invention;
FIGS. 8 and 9 are axial sections through further embodiments of a signalling device in accordance with the invention;
FIGS. 10 and 11 are axial sections taken at right angles to each other of a further signalling device in accordance with the invention;
FIGS. 12 and 13 are exploded views of the signalling device of FIGS. 10 and 11; and
FIGS. 14A and 14B are sectional views through diaphragms showing how diaphragms might be adapted for greater output.
The drawings are meant to be schematic representations only. Relative proportions are varied to accord with a need to explain the invention and do not necessarily represent what would be used in practice.
DETAILED DESCRIPTION
In FIGS. 1 to 4, signalling device 10 comprises a main body part 11 which is bored therethrough to serve as a cylinder for a piston of the type shown in FIG. 6. The bore in the main body part is closed at an air inlet end by an end cap 12. A locking ring 13 holds a diaphragm 22 at the other open end of the bore against the end of the main body part. End cap 12 may be provided with an external thread 14 which when in place engages in internal thread 15 of the main body part 10. An internal thread 16 on locking ring 13 may be used to engage with an external thread 17 on the main body part. End cap 12 may be provided with two externally accessible, shallow, closed bores 18 and 19 at which a suitable tool may be fitted to enable end plug 12 to be screwed into place. End cap 12 may be provided with a threaded bore 20 at which a compressed air line might be removably coupled. Any other suitable means of coupling a compressed air line may be used such as the well-known clip-on disconnectable couplings. Compressed air inlet 20 communicates in this embodiment with a transverse bore 21 which serves to pass compressed air which is supplied at the inlet by the air line to the chamber 33. At the other end of the main body part 11, the diaphragm 22 is held by a shoulder 23 on the locking ring 16 onto the inner edge of the outermost shoulder of the recess 24 at the end of the main body part 11. The recess 24 is provided to allow the diaphragm freedom to "ring", or rebound, after the initial piston (see FIG. 6) impact. The diaphragm 22 is held this way only at its periphery. Operation of the device is described below. The main body part 11 is provided with an axial bore 25 to communicate compressed air which axial bore 25 is in parallel with cylinder bore 26 in which a piston such as in FIG. 6 reciprocates. The main body part 11 is also provided with radial bores 27 and 28 as in FIG. 1 which each may have companion radial bores 29, 30 as seen in FIG. 4 which communicate the cylinder bore 26 with the outside of the main body part 11. A flapper valve as described with reference to FIG. 5 is located in chamber 33 between shoulder 31 and rear face 32 of end plug 12.
In the signalling device as set out above, a disc 109 of a material such as an ACETAL polymer might be fitted into the recess 24 behind diaphragm 22. This disc acts as a buffer between piston and diaphragm, spreading the piston impact over a larger surface area of the diaphragm.
The flapper valve of FIG. 5 is shown in an exploded view. The valve comprises a front case 35 and a rear case 34 which come together with a disc 36 in place therebetween in chamber 37. Disc 36 is free to move axially in chamber 37 to open or close various ports so as to create two separate flows of compressed air, 38, 39 depending upon the position of the piston of FIG. 6 as will be described below.
The piston 40 of FIG. 6 is cylindrical in section and it is provided with a rearward section 41 having a diameter which is a close sliding fit in cylinder bore 26. The piston 40 has a forward section 42 with a reduced diameter by which a chamber is created between the piston 40 and the main body part 11. The forward end 43 of piston 40 is, in use, driven against diaphragm 22 to generate an acoustic signal.
The piston of FIG. 6 might be designed for multiple impacts per stroke. This could be achieved by inclusion of a piston(s) within the main piston The diaphragm could then complete one or more complete cycles of oscillation following the initial piston impact before the second and subsequent pistons impact.
In operation of the above device, compressed air can be fed from a scuba diver's tank via a suitable line connected at inlet 20 of end plug 12. Compressed air will be permitted to follow one or the other of the flow patterns 38, 39 depending on the position of disc 36 which in turn depends on the position of piston 40. Ultimately the compressed air is vented to the outside through radial bores 27, 28, 29, 30. Flow 38 is communicated to axial bore 25 and via a cutaway at 44 to the front end faces 45, 43 of piston 40. Flow 39 is communicated to axial bore 26 and end face 46 of piston 40. If the piston is at rest on the diaphragm then lower port 28 is closed. The length of piston 40 is such that upper exhaust port 27 is open. When compressed air is turned on there is a pressure difference across the valve disc 36; a low pressure via path 39 to the open exhaust port 27; and a high pressure via path 38 to the closed lower exhaust port 28. In this circumstance disc 36 is driven hard against front case 35 shutting off path 39. The air supply is now direct=d via path 38 to the front end of piston 40 via bore 25 and opening 44 to act first on face 45 and then additionally 43 as piston 40 moves away from the diaphragm 22. When piston 40 is at the top of bore 26, lower exhaust port 28 opens causing a pressure drop in path 38. The piston closes upper exhaust port 29 creating a high pressure in path 39. The valve disc 36 is now driven hard against rear case 34 and the air supply drives piston 40 via path 39. The piston 40 now travels down cylinder 26 to bang against diaphragm 22 and generate an acoustic impulse when the cycle is repeated to create a pulsed output lasting as long as the air supply is switched to the signalling device.
A study of the drawings will show that the main body part, end plug, locking ring, diaphragm and piston may be manufactured using common fabrication techniques requiring little more than bores and threads for straight screwed connections. With the illustrated structure, there is no requirement for sealing of the piston. The main body part may be machined from a noncorrosive material, as might the end plug and locking ring. The diaphragm is preferably a plate of spring grade stainless steel and a 48 mm diameter diaphragm might be 0.56 mm thick. The piston may be machined from a block of engineering grade plastic and a PTFE material is preferable. Alternately the piston might be a metal/plastic combination.
FIG. 7 is a schematic layout of a double ended acoustic generator 47. A flapper valve is positioned at 52. It is positioned radially to control an air supply at line 53 feeding pressurised air alternately to inlet ports at the end of passages 112, 113. Opposed diaphragms 48, 49 are at each end of cylinder bore 50 wherein piston 51 is set to oscillate from one end to the other opening and closing exhaust ports 110, 111. Such an arrangement is topologically equivalent to the device of FIG. 1 so far as porting is concerned, a diaphragm replacing end plug 12. The axial valve of FIG. 1 is displaced sideways to a radial disposition. Such an arrangement can provide greater efficiency and a higher pitched and higher level acoustic output.
The signalling device of FIG. 8 has a main body part 54 which is bored to provide a cylinder 55 in which a piston (not shown) reciprocates as described with respect to the previous embodiments. End 56 is open for insertion of a flapper valve and a locking closure with air inlet of the same type as set out above in the foregoing embodiments. The opposite end of the cylinder is closed by diaphragm 57 which is clamped to shoulder 58 by locking ring 59. In this embodiment the locking ring 59 is provided with a skirt or sleeve 60 which encircles the main body part 54 to create an annular space 61 which is vented at 62 to the outside. Air which causes the piston to reciprocate is exhausted into annular space 61. The rearward vent 62 causes exhaust air to leave the device rearwardly, away from the diaphragm so as to avoid any power loss which would occur if the diaphragm was to act on water containing air bubbles.
In the embodiment of FIG. 9, like parts as seen in FIG. 8 are numbered similarly. In FIG. 9, the diaphragm 63 is larger and attached at its periphery to a flange 64, being held thereto by clamping ring 65 which might be held by screws such as 66 to flange 64. Flange 64 is integral with sleeve 67 which supports skirt 60. The larger diaphragm provides a means to generate more powerful acoustic signals.
The efficiency of the signalling device might be improved by placing a spring washer (spring steel, rubber, or other resilient material) between the diaphragm and locking ring.
FIGS. 10 and 11 are sections taken at right angles to each other through the same signalling device. The main body part 69 and a cylinder part 70 (seen in FIG. 11 only) are screwed together to establish the configuration of previous embodiments. The cylinder part 70 is threaded externally at both ends. The cylinder part 70 is screwed into the main body part 69 with, in use, a flapper valve (not shown) between the cylinder part 70 and the base of the bore in the main body part 69. A locking ring 71 screws onto the end of the cylinder part 70 to clamp a diaphragm 90 to the end of the cylinder. Piston 72 is seen in FIG. 11, reciprocating in the cylinder to open and close ports 73, 74 to exhaust pressurised air from the device. The ports 73, 74 exhaust air into space 75 which is enclosed by two skirts 91, 92 which meet at a gap at 76 over which a seal 93 may be applied. The seal 93 may be a round-sectioned ring of suitably resilient material such as an O-ring.
The signalling device of FIGS. 10 and 11 is provided with a push button 77 by which pressurised air fed to inlet 78 may be ported to passage 79 to the space 94 in which the flapper valve (not shown) is mounted. The push button 77 acts on a valve body 80 which is biassed by a spring 81 to engage against a valve seat 82. A pressurised air line may be attached at 107 by way of a snap-on or quick-connect valved coupling, e.g. SCUBA buoyancy compensating device (BCD) inflator hose and coupling. Outlet 83 with thread 84 may be either sealed with a screw-on cap or screwed into a variety of SCUBA BCD's to allow the use of a common pressure line for both BCD and signalling device. The outlet could also be a quick connector snap on type of coupling. The inlet 108 leads to a passage 85 which opens into space 86 which is sealed at each end by seals 87, 88 about an insert providing the coupling which is locked into a bore in the main body part by a lock nut or spring clip (circlip) 95. Space 86 opens into passage 89 in the main body part in which the valve body 80 is contained. Space 86 opens upstream of valve seat 82 and its operation vents pressurised air into passage 79 to the flapper valve to effect operation of the piston. The stem of FIG. 10 with the snap-on connector at one end and the screw connector at the other provides dual connectors for an in-line connection of the signalling device between tank and BCD to do away with a need for extra lines.
FIGS. 12 and 13 are exploded views of the parts of the device of FIGS. 10 and 11 shown in section view, the sections being orthogonal as with FIGS. 10 and 11. Like parts are numbered the same. The push button 77 has a seal 97 applied at 96 to seal its stem to the main body part 69. The stem is threaded at 98 to engage the valve body 80 at 99. The valve body 80 is provided with a seal 100 between it and the main body part and the spring 81 is captured in lock body 102 screwed into the main body part 69 and sealed thereto by seal 101.
The amount of power generated by the diaphragm might be set by the size of the diaphragm. Alternately, the diaphragm might be provided with concentric grooves or a spring washer between diaphragm 90 and locking cap 92 (diaphragm 22 and lock cap 13 of FIG. 1). FIGS. 14A and 14B are a sectional views through diaphragms 103, 104 showing cross-sections of possible grooves 105, 106. In practice, the diaphragm is a disc and the grooves or ribs would be provided concentrically in the disc with one or more grooves or ribs at different radii from the disc centre.
Devices in accordance with the invention can be run on a range pressures, typically 30 PSI to 3,000 PSI. This enables them to be run directly from a typical scuba tank where the flow volume is limited by the tank valve (even with the valve fully open) The smaller units of FIGS. 10 to 13 are designed to run at pressures up to 160 psi, specifically connected to the low pressure outlet of a scuba first stage.
The above described invention provides a device that may be used to signal between divers or between a surface boat and divers, etc, to create a signal as might be used to warn of problems.
The invention described above comprises a structure that is readily realised utilising readily machinable parts with a minimum of working parts by which to generate underwater signals It will be clear to those skilled in the art that the specific constructional details may be varied within the scope of the invention as set out in the following claims.
In the above embodiments, either of an axial input or a radial input is disclosed as set out in the drawings. It should be clear that this is optional and the alternate form of input might be used. Thus the embodiments of FIGS. 10 to 12 is readily redesigned with an axial input. | A signalling device for scuba divers uses their compressed air supply to drive a piston (42, 51, 72) against a diaphragm (22, 48, 49, 57, 63, 90) to generate sound in water against the diaphragm. A bistable valve 34, 52) switches pressurised air alternately to opposite ends of the piston (42, 51, 72) to cause it to reciprocate and repeatedly impact against the diaphragm (22, 48, 49, 57, 63, 90). Air is exhausted from the cylinder (11, 54, 70) through ports (27, 28, 29, 30, 110, 111, 73, 74), the ports being valved by movement of the piston. | 1 |
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to novel derivatives of pyrazine (substituted biphenyl pyrazines), to processes for preparing them, to compositions which contain the novel compounds, and to the use of said compositions for a wide variety of end use applications.
Related Applications
The present patent application is commonly owned by the same Assignee as the following cases:
(a) Ser. No. 08/326,104 filed Oct. 19, 1994, entitled "Polymer Compositions Containing Substituted Biphenyl Pyrazines".
Description of Related Art
The following prior art references are disclosed in accordance with the terms 37 CFR 1.56, 1.97, and 1.98.
Japanese patent publication no. 02-138267 (issued May 28, 1990) discloses the preparation of pyrazine derivatives for liquid crystals.
Japanese patent publication no. 02-072370 (issued Mar. 12, 1990) discloses electrophotographic photoreceptors containing pyrazine derivatives.
U.S. Pat. No. 3,761,477 discloses pyrazine-acetic acids, acetates, and acetamides which may be used as ultraviolet absorbers in plastics and resins.
U.S. Pat. No. 3,963,715 (issued Jun. 15, 1976) discloses various substituted pyrazines useful as dyes and pigments.
U.S. Pat. No. 5,099,344 (issued Mar. 24, 1992) discloses various substituted pyrazines useful in a ferroelectric liquid crystal device.
Bull. Soc. Chem. Fr., (12), 4970-4 (N. Vinot/J. Pinson) discloses various pyrazine derivatives.
Bull. Soc. Chem. Fr., p. 533 (1949) (G. Muller et al.) discloses the preparation of various pyrazine derivatives.
J. Chem. Soc. 97, p. 2495 (1910) discloses the preparation of various pyrazine derivatives.
Chemical Abstracts, Vol. 108, 1988, ( 151196t) discloses the use of various pyrazines for polyimides.
Chemical Abstracts, Vol. 108, 1988, (223028q) discloses the manufacture of polyester-polycarbonates using various pyrazines.
Chemical Abstracts, Vol. 114, 1988, (165442f) discloses polyaramids having incorporated therein various pyrazines.
Chemical Abstracts, Vol. 115, 1991, (49064f) discloses the preparation of various pyrazines useful as monomers and hardening agents for epoxy resins and urethane polymers.
Ueta et al., Polymer Journal, Vol. 24, No. 12, pp. 1429-1436 (1992) discloses the synthesis and properties of novel p-aramid including pyrazine ring.
All of the above-cited prior art patents and articles (and any others cited herein) are incorporated herein by reference in their entirety.
SUMMARY OF THE INVENTION
The present invention provides novel substituted biphenyl pyrazines or biphenyl pyrazine derivatives ("BPD") which are functional and have useful application as a monomer (co-monomer) for a variety of high performance polymers such as polyester, polyarylate, polycarbonate, polyetherketones, epoxides, polyimides, polyamides, and polyamides-imides; and as dyes and pigments for coating compositions such as paints. These BPD have the general formula: ##STR2## wherein R 1-8 and n are defined below.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides novel biphenyl pyrazine derivatives ("BPD") which are derivatives of substituted and unsubstituted acetophenone, e.g. 4-hydroxyacetophenone (4-HAP), which is a well-known basic building block for numerous organic chemicals. BPD, in turn, are building blocks for high performance polymers, heretofore mentioned, and pigment compositions. These BPD have the general formula: ##STR3## wherein n is 1 or 3, with the proviso that: A) where n is 1,
(i) R 1 and R 7 are each independently selected from the group consisting of H and --CH 2 C 6 H 5 ,
(ii) R 2 , R 3 , R 6 , and R 8 are each independently selected from the group consisting of H, halogen, NO 2 , NH 2 , N 2 ⊕, SO 3 H, SO 3 M (where m is an alkali metal such as sodium, potassium), C 6 H 5 , --OR 1 (R'═C 1-8 ), ##STR4## where R 9 and R 10 are each H, C 1 -C 6 , COOCH 3 , and COOC 2 H 5 , and Q 1 is NH or O; ##STR5## where R 11 is C 1 -C 6 ; ##STR6## where R 12 and R 13 are each independently selected from the group consisting of H, NO 2 , CN, halogen (eg. Cl), OCH 3 , COOH, COOCH 3 , NH 2 , ##STR7## with the proviso that at least one of R 2 , R 3 , R 6 , and R 8 must be other than H;
B) where n is 3, ##STR8## and R 2 , R 3 , R 6 , R 7 , and R 8 are the same as in (A) above;
C) where n is 1 or 3, R 4 and R 5 are each independently selected from the group consisting of H, NO 2 , NH 2 , and ##STR9##
Various BPD are set forth below to illustrate the compounds falling within Formula I above: ##STR10## where x and y are each independent and are either 0, 1, or 2, with the proviso that at least x or y must be 1 or 2 when the other is 0. ##STR11## where x is halogen such as chlorine, fluorine, or bromine; ##STR12## wherein R 14 , R 15 , R 16 , and R 17 are each independently selected from the group consisting of H, alkyl C 1 -C 6 , COOCH 3 , and COOC 2 H 5 , and Q 2 is NH or O. ##STR13## wherein R 18 and R 19 are each independently selected from the group consisting of H, alkyl C 1 -C 6 , COOCH 3 and COOC 2 H 5 .
In general, the substituted biphenyl pyrazines are prepared by self condensing a substituted alpha keto amine to form a substituted dihydropyrazine and then oxidizing the substituted dihydropyrazine to form the corresponding substituted biphenyl pyrazine. The substituted alpha keto amines, also called arylketoamines such as aminohydroxyacetophenone ("AHAP"), can be prepared by the methods described in copending U.S. patent application Ser. No. 08/191,849, now U.S. Pat. No. 5,349,090, entitled "Process for Preparing Arylketoamines" filed Feb. 4, 1994. The substituted alpha keto amines may also be prepared by those processes set forth in U.S. Pat. Nos. 1,995,709; 2,567,906; 2,505,645; 2,784,228; 3,028,429; 3,966,813; 5,124,489; and 5,198,585. All of these references are incorporated herein by reference in their entirety.
Where one so desires to start the preparation of the substituted biphenyl pyrazines or novel biphenyl pyrazine derivatives (all BPD) from a commercially available material such as a substituted or unsubstituted acetophenone (such as 4-hydroxyacetophenone, "4-HAP"), such acetophenone can be subjected to nitrite oxidation conditions to form the substituted or unsubstituted phenylglyoxal which, in turn, is oximated with a substituted amine to form the substituted or unsubstituted alpha-keto-oxime. This oxime is catalytically hydrogenated to form the corresponding substituted or unsubstituted alpha-keto-amine. The overall five-step method is set forth below in Scheme 1. Examples of materials used to facilitate the basic reaction are shown. In Scheme 1, Ar is representative of substituted phenyl groups in Formula I above. ##STR14##
In step (1), Scheme 1 above, an acetophenone, substituted or unsubstituted, is subjected to nitrite oxidation conditions to form the substituted or unsubstituted phenylglyoxal. The nitrite oxidation conditions consist of reacting such acetophenone (e.g. 4-HAP) in an aqueous medium with nitrosyl chloride (NOCl) to form the corresponding phenylglyoxal.
In step (2), Scheme 1 above, the phenylglyoxal is oximated with a substituted amine, such as NH 2 OH, to form the substituted or unsubstituted alpha keto oxime, such as 4-hydroxy-α-isonitrosoacetophenone ("HINAP").
In step (3), Scheme 1 above, the substituted or unsubstituted alpha keto oxime (e.g. HINAP) is subjected to catalytical hydrogenation to form the corresponding substituted or unsubstituted alpha keto amine. Such hydrogenation is effected by the use of hydrogen in the presence of a transition metal catalyst and a liquid carboxylic acid at a temperature of less than about 50° C., preferably from about 10° C. to about 35° C. Generally this reaction is conducted in the absence of a dipolar aprotic solvent. The liquid carboxylic acid is selected from the group consisting of formic, acetic, propanoic, butyric, valeric, caproic, heptanoic, octanoic, nonanoic, undecanoic, isobutyric, isovaleric, cyclohexane carboxylic acid, and mixtures thereof. The liquid carboxylic acid is further characterized by one which is capable of substantially dissolving the alpha keto oxime therein. The transition metal (catalyst) is selected from the group consisting of platinum, palladium, nickel, rhodium, and combinations thereof. This transition metal catalyst is preferably on an inert support such as carbon and/or barium sulfate. Where the aryl group is halogenated, it is desirable to use a Lindlar catalyst (e.g. palladium on barium sulfate) to insure halogen stability.
In step (4), Scheme 1 above, the substituted or unsubstituted alpha keto amine such as amino-hydroxyacetophenone (AHAP), are subject to self-condensing conditions to form the corresponding substituted or unsubstituted dihydropyrazine. These condensation conditions include the use of a dipolar aprotic solvent and a base material such as sodium or potassium hydroxide. Such dipolar aprotic solvents employed are solvents which have a high dielectric constant and a high dipole moment but no acid hydrogen atoms. Such solvents include, without limitation, dimethylsulfoxide (DMSO), acetonitrile, n-methyl-pyrrolidone (NMP), dimethylformamide (DMF), dimethylacetamide, and hexamethylphosphoric acid triamide (HMPT).
In step (5), Scheme 1 above, the substituted or unsubstituted dihydropyrazine is subjected to oxidation conditions to produce the substituted or unsubstituted pyrazines of the present invention. This oxidation reaction can employ any means to facilitate an oxidation of the dihydropyrazine to form the desired end product, i.e. BPD. This oxidation is generally conducted at a temperature less than those temperatures employed in step (4) above regarding the self-condensing action.
In conjunction with step 5 (Scheme I), the resultant product (starting from 4-HAP) will be 2,5-bis(4-hydroxyphenyl)pyrazine (sometimes referred to herein as "pyrazine") which has the following structure: ##STR15##
Since this can be easily made, it is preferred that this material be used as the starting material for the preparation of the novel substituted biphenyl pyrazines (BPD) of the present invention. The following schemes will illustrate the preparation of the various BPD following within Formula I above.
With reference to Scheme 2, the basic starting material, i.e. "pyrazine" (Formula VIII) can be subjected to nitration to form the dinitro "pyrazine" (Formula IX). The general reaction conditions are conducted at temperatures less than about 100° C., and preferably from about 0° C. to about 50° C. The reaction pressures can be subatmospheric, atmospheric, or super atmospheric. Where one so desires, suitable solvents can be employed to facilitate the reaction and used in place of water or as a co-solvent with water. The mononitro "pyrazine" (Formula X) can be prepared by the partial hydrolysis of the ester of pyrazine followed by partial nitration and partial hydrolysis as shown in the bottom portion of Scheme 2. The tetranitro "pyrazine" (Formula III, x=2 and y=2) can be prepared via nitration under more aggressive conditions, such as with mixtures of nitric and sulfuric acids. ##STR16##
Once the nitro compounds of Scheme 2 are prepared, these may be subjected to the following steps to form a wide variety of BPD as shown in Scheme 3.
______________________________________1) Reduction of nitro compounds preparation of amines2) Diazotization preparation of diazonium salts3) Diazo coupling preparation of pigments______________________________________ ##STR17##
The diazonium salts (Formula XII) can undergo additional coupling reactions as shown in Scheme 4 below. ##STR18##
As can be seen in Schemes 3 and 4 above, these process steps permit the preparation of BPD which fall within Formulae VI and VII set forth above.
Referring to Formula XII, the diazonium salts may be used in a similar manner to provide additional substrates for diazo coupling to the pyrazine. These substrates and the location of coupling are shown in Scheme 5 below (the arrow is the place of coupling). ##STR19##
The following process (Scheme 6) discloses the preparation of ring substituted amines and diazonium salts. ##STR20##
Scheme 7 shows the preparation of BPD wherein the pyrazine ring contains a halogen atom such as chlorine. In oxidizing the pyrazine ring, this is conducted with a peracid or perester, with or without a solvent. The most preferred oxidizing agent is hydrogen peroxide. Others, non-exclusively, include peracetic acid, alkyl peroxides, chloroperacetic acid, peroxybenzoic acid, and meta-chloroperoxybenzoic acid and trifluoro-peroxyacetic acid. Various solvents can be used in the overall reaction and these include, non-exclusively, water, alcohol, or polar aprotic solvents (e.g. ketones, ethers, nitriles, and sulfides), halogenated hydrocarbons, and carboxylic acids such as acetic acid. The reaction may take place at from about 0.01 to about 24 hours, or more preferably, from about 0.1 to about ten hours at a temperature of from about 0° C. to about 100° C., or more preferably, from about 25° C. to about 75°. The reaction may take place at either elevated or reduced pressures, in addition to atmospheric pressure. Where heat is generated during the reaction, it may be desirable to conduct the reaction at a reduced pressure in order to remove heat by evaporation of the solvent.
In Scheme 7, the chlorination can be conducted using any means to supply chlorine as long as such means do not prevent the basic reaction from taking place and/or promote the formation of undesirable by-products or the incorrect product. Scheme 7 shows the use of POCl 3 , but other chlorinating agents can be used. Likewise, other halogens can be similarly attached directly to the pyrazine ring. The reaction conditions are generally disclosed immediately above in describing the oxidation step.
In the third step in Scheme 7, the halogenated pyrazine ring compound (XVI) can then be subjected to a self-condensation step, under basic conditions, in order to add a second "pyrazine" substituent. This self-condensation step can be carried out in the same manner as described in step 4 of Scheme 1 above. ##STR21##
Scheme 8 discloses the preparation of BPD wherein n=3. In general, the process comprises reacting a trihalocyanurate, such as trichlorocyanurate, with the basic "pyrazine" (Formula VIII) in a base material, such as sodium hydroxide, with or without a suitable solvent (the temperatures and pressures are not critical). The temperature is generally in the range of from about 0° C. to about 150° C. ##STR22##
Scheme 9 discloses the preparation of BPD by the diazo coupling of pyrazine with anilines. The scheme 9 chart also discloses other anilines that can be used for the diazo coupling. Examples of anilines and substituted anilines are as follows: ##STR23## where R and R' are each independently selected from the group consisting of H, NO 2 , Cl, CH 3 , OCH 3 , COOH, COOCH 3 , NH 2 , C(O)N(H)C 6 H 5 , and --C 6 H 4 NH 2 . ##STR24## where R 20 , R 21 , R 22 , and R 23 are each independently selected from the group consisting of H, Cl, CH 3 , and OCH 3 .
The diazo coupling outlined herein and with reference to Scheme 9 can be carried out by those processes well-known in the an and also as outlined in Organic Chemistry, 3rd Edition, Morrison & Boyd, 1973, Allyn & Bacon, Inc. (Boston), p. 765-775, which book is incorporated herein by reference in its entirety.
The BPD can be incorporated into various polymers, either chemically or mechanically, by those methods disclosed in the references herein before cited and also U.S. Pat. Nos. 4,665,178; 3,882,122; 5,099,027; 4,508,882; and 3,862,087; all of which are incorporated herein by reference in their entirety.
The BPD can be incorporated into various materials, including polymers, as pigments therefor by processes described in U.S. Pat. Nos. 3,97,386; 4,053,463; 4,053,464; 4,334,932; 4,082,741; 4,070,353; 4,065,448; 4,062,838; 4,024,124; 4,006,162; and 4,367,173; all of which patents are incorporated herein by reference in their entirety.
The following specific examples are supplied for the purpose of better illustrating the invention. These examples are not intended, however, to limit or restrict the scope of the invention in any way and should not be construed as providing conditions, parameters, or values which must be utilized exclusively in order to practice the present invention.
EXAMPLE 1
Preparation of 2,5,-Bis(4-hydroxyphenyl)pyrazine (Formula VIII)
A 500 ml three-neck round-bottom flask is fitted with a magnetic stirrer, nitrogen inlet, heating mantle, thermometer, and an upright water-cooled condenser. The vessel is charged with α-amino-4-hydroxyacetophenone acetate salt (AHAP.AcOH), 10.0 g (containing 6.69 g AHAP free base). Potassium acetate, 11.6 g, is added, followed by 160 g DMSO.
The contents of the vessel are heated to 70° C. and the temperature is maintained at 70° C. with stirring for three hours. The reaction is allowed to cool to 50° C. and the nitrogen is discontinued. Air is bubbled into the reaction overnight (16 hours) at 50° C. A dark red solution is observed and is obtained by filtering hot and the filtrate is diluted with 508.5 g distilled water which creates an exotherm. The aqueous reaction mixture is allowed to cool to ambient temperature (i.e. about 20° C.) and crystallization is allowed to continue for six hours. The dark supernatant liquid is syphoned off and the remaining slurry is gradually and gently suction-filtered on a Buchner filter.
The filtrate is rinsed with 150 g of deionized water. The product is air-dried for four hours, then is dried at house vacuum at 60° C. overnight. The residual yellow solid (4.1 g) is submitted for liquid chromatograph (LC) analysis. Purity by LC is 94.8%. FTIR, 1 H and 13 C-NMR are consistent with the assigned structure of 2,5-bis(4-hydroxyphenyl)pyrazine. Mass spectroscopy confirms the expected MW 264. The yield of the pyrazine, based on AHAP, is 66.7%
EXAMPLE 2
Preparation of 2.,5-Bis(4-hydroxyphenyl)pyrazine from 4-Hydroxyacetophenone
A two liter five-neck round-bottom flask is charged with 4-hydroxyacetophenone (4-HAP) (100 g, 0.74 mol) followed by the addition of 286 g water and 31% of aqueous HCl (383.3 g, 3.31 mole). The reaction mixture is stirred and heated to 55° C. Aqueous solution of 42% NaNO 2 (286 g, 1.62 mol) is added to the generator at a rate of 2.9 grams per minute (100 minute addition). The temperature is maintained at 55° C. After NaNO 2 addition is complete, the reaction is continued for another thirty minutes to remove the remaining NOCl. Analysis of the reaction mixture indicates the presence of 9.89 weight percent HPGO (hydroxyphenyl glyoxal) which corresponds to a HPGO yield of 83.3%. The reaction mixture is then cooled to 40° C. and then hydroxylamine free base (112 g, 0.882 mol) is added over a period of ninety minutes. After the addition is complete, the reaction mixture is cooled to 5° C. Filtration affords a solid (114 g). Analysis indicates that the solid contains 14% H 2 O, 76% HINAP (4-hydroxyisonitrosoacetophenone), 3% HPGO, 2% 4-HAP and 4% unknown. This corresponds to isolated HINAP to be 72%.
Dry HINAP (13.8 g, 0.082 mol, from the above procedure) is added to a 300 ml autoclave, which is charged with 1.38 g of 50% wet (5% palladium on carbon) and 175 ml of dry EtOH and catalytic amount of HOAc (1 ml). The reactor is sealed then degassed three times with nitrogen and three times with hydrogen. The reactor is then pressurized to 50 psi with hydrogen and stirred at 1200 rpm. The reaction consumes two equivalents of hydrogen. The rate of hydrogen consumption is very slow. The reaction is allowed to react a ambient temperature for 19 hours. The reaction heats itself from 22° C. to 27.6° C. The reaction mixture at the end of the reaction is a slurry. Air is bubbled through the reaction mixture to aromatize the dihydropyrazine to pyrazine. The insoluble mixture of the pyrazine monomer and the palladium catalyst are treated with 10% NaOH to pH=8. The reaction mixture is stirred until all the pyrazine is dissolved and only then is the catalyst filtered. The reaction mixture is treated with acid to pH=6 and the mixture is concentrated under reduced pressure. Analysis indicates the presence of the pyrazine [2,5-bis(4-hydroxyphenyl)pyrazine] as the major product in 60% yield (75% selectivity).
This example shows the preparation of a substituted pyrazine via the "in-situ" formation of AHAP without the necessity of actually having to form the AHAP, separating it and then reacting it in the presence of a dipolar aprotic solvent and a base material as shown in step (4), Scheme 1 above.
EXAMPLE 3
Preparation of 2,5-Bis(4-hydroxy-3-nitrophenyl)pyrazine (Formula III, x=1 and y=1)
To a three-neck two-liter round-bottom flask equipped with a magnetic stirrer there is charged 883 grams (9.88 moles) HNO 3 (70.5%). The contents are continuously stirred and maintained at 5° C. with the provision of an ice bath. Fifty-three grams of 2,5-bis(4-hydroxyphenyl) pyrazine (Example 2 ) are added to said flask, in ten-gram portions, in order to maintain a 10° C. temperature level of the flask contents. Upon the addition of pyrazine, the solution turns red. After the pyrazine addition is complete, the ice bath is removed and the flask contents are allowed to warm to room temperature (approximately 20° C.). Stirring is continued at room temperature for an additional hour. The product is precipitated by slowly pouring it into four liters of deionized water. The resultant mass is stirred for thirty minutes and then is filtered. The product crystals are washed with four liters of deionized water. The crystals are air-dried with suction on a fritted funnel and placed in an oven at 100° C. under vacuum overnight. NMR identifies the material to be the compound of Formula IX above.
EXAMPLE 4
Preparation of2,5-Bis(4-hydroxy,3,5-nitrophenyl)pyrazine (Formula III, x=2 and y=2)
To an eight-ounce screw cap bottle fitted with a magnetic stirrer there is charged 72 grams (0.81 moles) HNO 3 . Four grams of pyrazine are added in portions in order to maintain the resultant mixture at less than 10° C. The mixture becomes red upon addition of 2,5-bis(4-hydroxyphenyl)pyrazine (Example 2). After the pyrazine addition is complete, the ice bath is removed and the overall reaction mass is allowed to warm to room temperature (approximately 20° C.). The contents are then stirred at 20° C. for 16 hours. The contents are then cooled to 5° C. by the use of an ice bath and then 36 grams concentrated sulfuric acid is added, dropwise, to the reaction mass while continuously stirring. The dropwise addition facilitates maintaining the contents' temperature at less than 12° C. The resultant mixture becomes orange upon addition of sulfuric acid. The reaction mixture is then stirred for an additional 16 hours. The product is precipitated by slowly pouring it into 380 grams of ice water. The overall mixture is stirred for 20 minutes and then vacuum filtered. The resultant crystals are then rinsed with an additional 380 grams of deionized water. The crystals are air-dried with suction on a fritted funnel and dried in an oven at 100° C. under vacuum overnight. NMR identifies the material to be the compound of Formula III above where x=2 and y=2.
EXAMPLE 5
Sulfonation of 2,5-Bis(4-hydroxyphenyl)pyrazine
To a three-neck 100 ml round-bottom flask fitted with an ice bath and mechanical stirrer there is charged 60 grams of fuming sulfuric acid (30% oleum) while stirring. Ten grams of2,5-bis(4-hydroxyphenyl)pyrazine is added in portions and the temperature is maintained at 50° C. Stirring is then conducted for four hours at 50° C. The product is precipitated by pouring the contents into 30 grams of deionized water. The overall mixture is filtered via vacuum and air-dried. NMR identifies the material to be 2,5-bis(4-hydroxy-3-sulfonic acid phenyl)pyrazine.
EXAMPLE 6
Hydrogenation of 2,5-Bis(4-hydroxy-3-nitro phenyl)pyrazine (Formula IX)
To a 100 cc autoclave equipped with a hydrogen inlet and a heating jacket there is charged 5.0 grams (0.01 moles) of dinitro "pyrazine", 0.2 grams of Pd/C catalyst and 47.0 grams of DMF. The autoclave is heated to the temperatures indicated below for the period of time set forth below and hydrogen gas supplied at the pressures indicated below:
______________________________________Temp °C. Time (Hours) H.sub.2 Pressure (psi)______________________________________50 0.5 175 1.5 1100 2.5 100100 1.0 200100 0.5 300100 1.0 425______________________________________
At the end of this 7.0 hour run, the autoclave is cooled by removing the heating fluid and then the contents removed and filtered over celite. The autoclave is washed with DMF and combined with the overall reaction mass which is then filtered. The filtrate is precipitated via pouring in water. The overall mixture is filtered via vacuum and the solids are air-dried on a fritted funnel. NMR identifies the material to be a compound having the Formula XI above.
EXAMPLE 7
Preparation of 2,4,6-tri[2,5-Bis(p-hydroxyphenyl pyrazine]-1,3,5-Triazine
To a two-liter, three-neck, round-bottom flask equipped with a magnetic stirrer there is charged 18.3 grams (0.1 mole) trichlorocyanurate, 79.2 grams (0.3 moles) 2,5-bis(4-hydroxyphenyl) pyrazine, 12.0 grams (0.3 moles) NaOH, and 60 milliliters of NMP. With continuous stirring, the resultant reaction mass is heated to 100° C. and maintained at this temperature for 7.5 hours. At the end of this time, heating is discontinued and the reaction mass is allowed to cool to room temperature (approximately 20° C.). Stirring is continued at room temperature for one additional hour. The product is precipitated by slowly pouring it into four liters of deionized water. The resultant mass is stirred for 30 minutes and then filtered. The product crystals are washed with four liters of deionized water. The crystals are air-dried with suction on a fritted funnel and placed in an oven at 100° C. under vacuum overnight. NMR identifies the material to be the compound of Formula II, i.e. the above-described triazene.
EXAMPLE 8
Preparation of2.,5-Bis[4'-hydroxy-3'-(2-nitrophenyl azo)phenyl]pyrazine
To a two-liter, thee-neck, round bottom flask equipped with a mechanical stirrer, digital thermometer, heating mantle, and nitrogen inlet there is charged (a) 260 ml tap water; (b) 16 ml of a 50% by weight solution of sodium hydroxide (0.2 moles); (c) 15.0 grams (0.1416 moles) of sodium carbonate (soda ash); and (d) 83.4 grams (0.20 moles) of 2,5-bis(4-hydroxyphenyl)pyrazine The resultant mass is stirred overnight. Two hundred grams of ice is added to the flask and the overall contents are stirred for 30 minutes (the internal temperature is 0° C.). The diazo compound (166.8 grams) and the orthonitroaniline (converted to a diazonium solution) are placed in an addition funnel and are added dropwise to the contents of the flask over period of two hours, The temperature rises to 15° C. toward the end of the addition and the resultant mass contents are stirred overnight without temperature control. The azo dye product precipitates and is removed from the solution by suction filtration using a course-sintered glass funnel. The wetcake is approximately 30% by weight solids and is dried in a vacuum oven overnight at 100° C. NMR analyses show the product to have the formula: ##STR25##
In addition to the chemical name set forth in the title of Example 8, the product also has the name 4,4'-(2,5-Pyrazinediyl)Bis[2-[(2-Nitrophenyl)Azo]-Phenol].
EXAMPLE 9
Preparation of a Polysulfone Copolymer Using 2,5-Bis(4-hydroxy-3-aminophenyl) pyrazine
To a three-neck, one-liter flask fitted with a thermowell, mechanical stirrer, and distillation head there is added bisphenol-A (22.8 g, 0.10 mol), 4-fluorophenylsulfone (29 g, 0.10 mol), 2,5-bis(4-hydroxy-3-aminophenyl)pyrazine (0.267 g, 0.001 mol) and potassium carbonate (27.88 g, 0.20 mol). Once all the reactants are added, 150 g of N-methylpyrrolidinone and 50 g of toluene are added, and the mixture is stirred at room temperature until most of the reactants dissolve. The pale yellow solution is stirred while the temperature is increased from 25° C. to 165° C. over a two-hour ramp. Removal of the water is accomplished by azeotroping with toluene. The temperature is held at 165° C. for sixteen hours, then ramped to 175° C. in five minutes and is held there for two hours. A dark brown solution forms and is allowed to cool to room temperature. The solution is decanted from the residual salts and precipitates into isopropanol/acidified water, 75/25. The resulting solid is filtered, re-dissolved into THF, and precipitated again into isopropanol. The resulting white polymer is filtered and dried in a vacuum oven at 100° C., yield 48 g. The intrinsic viscosity, measured in 1,1,2,2-tetrachloroethane at 30° C., is 0.35. This polymer shows an increase in thermal properties and chemical resistance.
EXAMPLE 10
Preparation of a Polyarylate Copolymer Using 2,5-Bis(4-hydroxy-3-aminophenyl)pyrazine
A heterogeneous solution of 2,5-bis(4-hydroxy-3-aminophenyl)pyrazine (2.99 g, 8.7 mmol), bisphenol-A diacetate (2.68 g, 8.6 mmol), terephthalic acid (0.71 g, 4.3 mmol) and isophthalic acid (2.14, 12.9 mmol) is heated to 240° C. in 50 g Dowtherm A (a 50:50 weight ratio of bisphenol A diacetate to pyrazine). The reactants dissolve at 240° C. to form a clear yellow solution. A white precipitate forms with prolonged heating. Heating is continued for an additional four hours at 260° C. A white precipitate is recovered by filtration and washed several times with acetone to remove any residual Dowtherm A, yield 75%. The white polymer melts at 266° C., as measured by DSC. This polymer displays an increase in crystalline structure and strength and exhibits liquid crystal properties.
EXAMPLE 11
The procedure set forth in Example 10 is repeated, however, the ratio of bisphenol-A to pyrazine is changed to 80:20, respectively. A melting point is detected at 266° C., along with a broad exotherm centered at 400° C. Properties of this polymer are similar to those of the polymer in Example 10.
EXAMPLE 12 (COMPARATIVE)
The procedure set forth in Example 11 above is used to make a bisphenol-A based polyarylate without the incorporation of the pyrazine therein. Thermal analysis of this polymer shows only a glass transition temperature at 195° C., no melting point is observed. This polymer is inferior than that polymer of Example 11 which incorporates the pyrazine.
EXAMPLES 13-27
Preparation of Polymer Compositions
Various polymer compositions comprising the particular polymer having incorporated therein the specific substituted pyrazine are prepared using known methods in the polymer composition art (such as U.S. Pat. No. 4,716,234). The specific polymers are set forth in Table 1. The pyrazine formula is that compound which is disclosed herein above in structural formula. The polymers listed in Table 1 are those polymers which are found to be suitable to have the pyrazines (listed) used therein. Each of these pyrazines are found to be suitable in the (listed) polymers and enhance the physical and chemical properties thereof.
TABLE 1______________________________________ Pyrazine Comments*Example No. Formula Polymer 1 2 3______________________________________13 II Polyester + + +14 III (x & y = 2) Polyester + + +15 IV Epoxide + + +16 V Polyetherketone + + +17 VI (R.sub.14-17 = H) Polycarbonate + + +18 VII (R.sub.18-19 = H) Epoxide + + +19 IX Polyimide + + +20 X Polyamide + + +21 IX Polyamide-imide + + +22 XI Polyarylate + + +23 II Polyetherketone + + +24 XIII Polycarbonate + + +25 XIV Polyamide + + +26 XVII Epoxide + + +27 XVI Epoxide + + +______________________________________ *1. Increase in thermal properties (over base polymer) 2. Increase in tensile strength (over base polymer) 3. Increase in modulus (over base polymer)
The novel substituted biphenyl pyrazines of this invention are highly colored materials and suitable for use as dyes and pigments.
EXAMPLES 28-32
The novel compounds are useful as dyes, particularly for hydrophobic fibers, e.g., polyester fiber and blends of polyester with cotton, polyacrylonitrile fiber, etc. The dyeing procedure frequently employed is the thermosol dry heat process. For example, a dye paste is prepared by sand milling a mixture of 7.6% (2,5-bis(4-hydroxy-3-nitrophenyl) pyrazine (from example 3 above) and 15.2% lignin sulfonic acid dispersing agent in water. A sample of a 65/35 polyester/cotton blend fabric is padded at room temperature to 50% pickup, based on the dry fabric weight, in a dye bath prepared by addition of the dye paste to water at the rate of 5.9 g paste to 1 liter of water. The padded material is passed through an infrared pre-drier, dried further in a dry box at 180° F., and then heated at 415° F. for 90 seconds. The fabric is then padded at 100° F. in a bath containing 40 g per liter of sodium hydrosulfite and 50 g/liter of sodium hydroxide. The material is steamed for 30 seconds at 212°-220° F., rinsed in water at 80° F. for two minutes, and oxidized for ten minutes in a bath at 120° F. containing 2.5 g/liter of sodium perborate and 1 g/liter of acetic acid. The fabric is then rinsed in water at 80° F. and soaped for five minutes at 200° F. in a bath containing two g/liter of a sodium ether-alcohol sulfate and 1 g/liter of sodium carbonate. Finally, the cloth is rinsed in water at 80° F. and air-dried at 180° F. The cloth is dyed a yellow. The dye exhibits excellent sublimation fastness. In a similar manner, the substituted biphenyl pyrazines (from examples 4, 5, 6, and 7 above) are successfully used to dye the polyester in a fabric of 65/35 polyester/cotton blend.
EXAMPLE 33
To a solution of 0.02 g of the sulfonic acid-paste product of Example 28 in 2 ml of water is added 0.41 g of multifabric swatch. The pH is about 2-3. The fabric is heated at 51° C. for 15 minutes, removed, rinsed three times with water, and dried at 100° C. in a vacuum oven. Nylon is dyed bright yellow; flanking sections of polyester and polyacrylonitrile remain white; silk is dyed medium yellow-brown; wool, yellow; acetate, Acrilan 1656 and Arnel pale yellow; cotton, Verel T5, and viscose very pale yellow.
When the pH is adjusted to above pH 11 with 0.2 ml 1N NaOH and the dyeing process repeated, no dyeing of the cloth occurs.
EXAMPLE 34
A small sample of the product of Example 3 is ground between glass plates using toluene as a lubricant. Then Datakoat (a toluene-soluble, plasticized acrylic resin in a spray can by Datak Corp., Pasaic, N.J.) is sprayed on the finely divided mixture and thoroughly mixed by rubbing between glass plates and scraping with a razor blade. The yellow mixture is applied to paper and dried to give a bright yellow smudge-proof finish.
In another facet of the present invention, it has been found that the novel BPD are useful as pH-sensitive pigments. In these cases, the BPD are one color in their original form but when exposed to a basic material (such as NA 2 CO 3 and/or NaHCO 3 ) turn a different color and then, upon further exposure to an acidic material (such as HCL), they return to their original color. Thus, where one incorporates such BPD in a crating composition along with a basic material and the color turns different and this crating composition is applied to a pipe carrying acid, if such pipe were to leak acid, the crating composition would turn a different color (i.e. back to the original BPD color) and be indicative (or an indicator) that the pipe was leaking acid. The utility of this facet of the present invention is quite unique.
Although the invention has been illustrated by certain of the preceding examples, it is not to be construed as being limited thereby; but rather, the invention encompasses the generic area as hereinbefore disclosed. Various modifications and embodiments can be made without departing from the spirit and scope thereof. | The present invention provides novel substituted biphenyl pyrazines or pyrazine derivatives ("BPD") which are functional and have useful application as a monomer for a variety of high performance polymers such as polyester, polyarylate, polycarbonate, polyetherketones, epoxides, polyimides, polyamides, and polyamides-imides; and as pigments for coating compositions such as paints. These BPD have the formula: ##STR1## | 2 |
This application is a continuation-in-part of Ser. No. 07/691,201 filed Apr. 25, 1991, now U.S. Pat. No. 5,200,034.
BACKGROUND OF THE INVENTION
Dry toner electrostatic printing inks, including laser and xerographic inks, are important and growing contaminants in the area of waste paper recycling. Traditionally, paper has been printed with water or oil-based inks which were adequately removed by conventional deinking procedures. In these methods, secondary fiber is mechanically pulped and contacted with an aqueous medium containing a surfactant. Ink is separated from pulp fibers as a result of mechanical pulping and the action of the surfactant. The dispersed ink is separated from pulp fibers by such means as washing or flotation.
Conventional deinking processes have shown minimal success in dealing with dry toner electrostatic printing inks, with the necessary chemical and mechanical treatments of the furnish proving to be time consuming and often rendering a furnish which is unacceptable for many applications. The development of a deinking program for office waste contaminated with electrostatic printed copy will make this furnish more amenable to the recycling process.
The ability to recycle office waste will prove commercially advantageous and will have a significant impact on the conservation of virgin fiber resources. Although electrostatic printed waste has not reached the volume of impact printed waste commonly seen in the industry, indications are such that usage of electrostatic print is increasing steadily and that waste copies available to the recycling industry will also increase.
The present invention enhances the aggregation and subsequent removal of electrostatic toner particles through centrifugal cleaners by using specific commercially available raw materials. This can be accomplished at a wide range of pH levels (5.0 to 11.0) and will render a furnish that is virtually free of electrostatic printing ink after subsequent mechanical treatment. The invention allows for the separation of ink particles and associated binder from pulp fibers, and causes the particles to aggregate to a critical range of size and density, which affords their most efficient removal from the pulp slurry by centrifugal cleaners.
The present invention demonstrates that specific surfactants with low HLBs enhance the aggregation of electrostatic toner particles, allowing removal through centrifugal cleaning and/or screening. HLB is an abbreviation for hydrophile-lipophile balance as related to the oil and water solubility of a material. A high HLB indicates that the hydrophilic portion of the molecule is dominant, while a low HLB indicates that the hydrophobic portion of the molecule is dominant. The water solubility of materials increases with increasing HLB. Traditional deinking processes utilize a wide variety of high HLB (generally greater than 10) nonionic and/or anionic surfactants or dispersants to wet and disperse ink particles to a range of size (about 0.5 to 15 microns) which allows for their most efficient subsequent removal by washing and/or froth flotation processes.
Aggregation is seen at pH levels ranging from 5.0 to 11.0, with no significant deposition of ink present on pulping equipment. The advantage of the present invention is that it allows for aggregation at an ambient pH, alleviating the need for caustic or acid tanks in the mill environment.
SUMMARY OF THE INVENTION
The components of the present invention comprise individual surfactants with hydrophile/lipophile balances of from about 0.5 to 10.0. These components will also be effective when combined with aliphatic petroleum distillates (solvents). (The solvents are saturated hydrocarbons having carbon numbers in the range of C9-C12). All components are commercially available.
DETAILED DESCRIPTION OF THE INVENTION
The present inventors have discovered that the addition to an aqueous slurry of electrostatic printed wastepaper of a surfactant with a hydrophile/lipophile balance of from about 0.5 to 10.0 significantly enhances the aggregation of electrostatic toner particles, allowing for their separation from fiber through centrifugal cleaning and/or screening. This aggregation takes place at pH levels ranging from about 5.0 to 11.0, with no significant deposition of ink present on pulping equipment. (A pH higher than 11.0 or lower than 5.0 is also believed to be effective).
During initial testing, the phenomenon was termed agglomeration (i.e., a bringing together of particles, the surface area of the whole remaining the sum of each individual part). The inventors now feel that a more accurate term to describe the phenomenon is aggregation (i.e., a changing of surface area, the total surface area being less than the sum of the individual particles). Aggregation is a result of this densification, or reduction of void areas.
The individual surfactants (e.g., ethoxylated, propoxylated, ethoxylated/propoxylated, esterified or alkanolamide) allow for aggregation at an ambient pH, alleviating the need for caustic or acid tanks in the mill environment. The raw materials which are effective in this invention include:
1. Alkylphenol ethoxylates
2. Block copolymers of ethylene oxide and propylene oxide
3. Alcohol ethoxylates
4. Glycerol esters
5. Alkoxylated fatty esters
6. Sorbitan esters
7. Fatty acid alkanolamides
8. Amine ethoxylates
9. Dimethylpolysiloxane alkoxylates
The chemical structures of the raw materials are as follows:
______________________________________Alkylphenol ethoxylatesEthoxylated OctylphenolsC.sub.8 H.sub.17 C.sub.6 H.sub.4 O(CH.sub.2 CH.sub.2 O).sub.n Hn = 1-6Ethoxylated NonylphenolsC.sub.9 H.sub.19 C.sub.6 H.sub.4 O(CH.sub.2 CH.sub.2 O).sub.n Hn = 1-6Dodecylphenol EthoxylatesC.sub.12 H.sub.25 C.sub.6 H.sub.4 O(CH.sub.2 CH.sub.2 O).sub.n Hn = 1-6Dialkylphenol Ethoxylates ##STR1##n = 1-9R.sub.1, R.sub.2 = C.sub.8 H.sub.17, C.sub.9 H.sub.19 or C.sub.12H.sub.25Block copolymers of ethylene oxide and propylene oxideEthoxylated Polyoxypropylene Glycols ##STR2##n = 1-45m = 14-77Propoxylated Polyoxyethylene Glycols ##STR3##n = 14-77m = 1-45Alcohol EthoxylatesPrimary Alcohol EthoxylatesCH.sub.3 (CH.sub.2).sub.x CH.sub.2 O(CH.sub.2 CH.sub.2 O).sub.n Hx = 4-16n = 1-10Secondary Alcohol Ethoxylates ##STR4##n = 1-8m = 9-12Glycerol EstersGlycerol Esters of Fatty Acids ##STR5##R, R.sup.1, R.sup.2 = caprylic, capric, lauric, myristic,palmitic, palmitoleic, stearic, oleic, linoleic, linolenic,alpha-eleostearic, ricinoleic, gadoleic, arachidonic,behenic, pelargonic, iso-oleic, or iso-stearicR.sup.1, R.sup.2 = HAlkoxylated Fatty EstersEthoxylated Fatty Esters ##STR6##n = 1-9R, R.sup.1 = caprylic, capric, lauric, myristic, palmitic,palmitoleic, stearic, oleic, linoleic, linolenic, alpha-eleostearic, ricinoleic, gadoleic, arachidonic, behenic,pelargonic, iso-oleic, or iso-stearicR.sup.1 = HPropoxylated Fatty Esters ##STR7##n = 1-10R, R.sup.1 = caprylic, capric, lauric, myristic, palmitic,palmitoleic, stearic, oleic, linoleic, linolenic, alpha-eleostearic, ricinoleic, gadoleic, arachidonic, behenic,pelargonic, iso-oleic, or iso-stearicR.sup.1 = HSorbitan Esters ##STR8##R = caprylic, capric, lauric, myristic, palmitic,palmitoleic, stearic, oleic, linoleic, linolenic,alpha-eleostearic, ricinoleic, gadoleic, arachidonic,behenic, pelargonic, iso-oleic, or iso-stearicFatty Acid AlkanolamidesFatty Acid Diethanolamides ##STR9##R = caprylic, capric, lauric, myristic, palmitic,palmitoleic, stearic, oleic, linoleic, linolenic,alpha-eleostearic, ricinoleic, gadoleic, arachidonic,behenic, pelargonic, iso-oleic, or iso-stearicR.sup.1, R.sup.2 = H, CH.sub.2 CH.sub.2 OH, or ##STR10##Amine EthoxylatesEthoxylated Tertiary Amines ##STR11##R = caprylic, capric, lauric, myristic, palmitic, palmitoleic,stearic, oleic, linoleic, linolenic, alpha-eleostearic,ricinoleic, gadoleic, arachidonic, behenic, pelargonic,iso-oleic, iso-stearic, or rosinx = 1-6y = 1-6______________________________________
Dimethylpolysiloxane ethoxylates and propoxylates (molecular weight=600-20,000), as well as sorbitan ester ethoxylates are also anticipated to be effective surfactants in the aggregation of electrostatic toner particles.
For the application of electrostatic toner particle aggregation, the effective hydrophile - lipophile balance of the tested surfactants is from about 0.5 to 10, preferably from about 0.5 to 5. It is believed that the effective temperature range for the aggregation of electrostatic toner particles is from about 110°-190° F.
A beaker test method was utilized to determine the impact of various raw materials on toner aggregation without the presence of fiber. This method allowed for the visual evaluation of toner configuration after treatment and permitted the particles to be sized using the Brinkmann Particle Size Analyzer. When raw materials were screened using this method, those demonstrating significant particle aggregation were advanced to the Dsinking/Repulping Apparatus (the pulper) for an evaluation of performance in the presence of fiber.
The experimental procedure was as follows: Approximately 0.01 grams of toner was added to a beaker containing 100 milliliters of deionized water. Each solution of toner and water was mixed on a magnetic stirrer at a pH of 7.0, a temperature of 150° F. and a contact time of 60 minutes. About 514 parts of raw material per million parts of solution was added to the beaker. Upon completion of contact time, particle configurations were noted, and solutions were filtered and held for size evaluation using the Brinkmann Particle Size Analyzer.
The pulper was then used to evaluate selected raw materials. This apparatus consists of a Waring blender jar with the blades reversed to provide a mixing action of the fibers. The stirring of the blender is controlled by a motor connected to a Servodyne controller. Temperature of the pulp in the blender is provided by a heating mat attached to a temperature controller. The typical furnish consistency in the laboratory pulper is 5%, and a stirring speed of 750 rpm is used to simulate the mechanical action of a hydropulper.
Electrostatic printed wood-free fiber was used as the furnish. Twenty pounds of raw material per ton of fiber were added to the pulper (5-20 pounds material/ton of fiber the preferred range, 10-20 pounds/ton most preferred) at a temperature of 150° F., a pH of 7.0, and a pulping time of 60 minutes. In Table 1, toner particle aggregation or the lack thereof through the use of individual surfactants is listed.
TABLE 1__________________________________________________________________________Toner Particle AggregationFUNCTIONAL TONER PARTICLEGROUP HLB APPEARANCE*__________________________________________________________________________Ethoxylated 3.6 aggregated n = 1.5Octylphenols 15.8 no effect n = 10.0Ethoxylated 4.6 aggregated n = 1.5Nonylphenols 12.9 no effect n = 9.5 17.2 no effect n = 49Ethoxylated 0.5 aggregated n = 9 m = 69Polyoxy- 1.0 aggregated n = 13 m = 56propylene 18.5 no effect n = 3 m = 15Glycols 1.0 aggregated n = 13 m = 56 12.0 no effect n = 3 m = 16Primary 4.6 aggregated n = 2.0 x = 16Alcohol 12.2 no effect n = 9.0 x = 16Ethoxylates 6.0 aggregated n = 4.0 x = 6-8Glycerol 0.8 aggregated R = R' = OleicEsters of 1.6 aggregated R = Oleic, R' = HFatty Acids 2.5 aggregated R = Oleic, R' = H 2.7 aggregated R = Oleic, R' = H 2.7 aggregated R = Stearic, R' = H 2.9 aggregated R = Isostearic, R' = H 2.8 aggregated R, R' = Fatty AcidEthoxylated 8.0 aggregated n = 5 R = Oleic, R' = HFatty Esters 13.5 no effect n = 14 R = Oleic, R' = H 2.0 aggregated n = 1 R = Stearic, R' = H 3.0 aggregated n = 1 R = Stearic, R' = H 18.0 no effect n = 40 R = Stearic, R' = HPropoxylated 1.8 aggregated R = Stearic, R' = H(monoester)Fatty 1.8 aggregated R = Stearic, R' = H & StearicEsters (at least 95% monoester) 3.5 aggregated R = Stearic, R' = H & Stearic (at least 67% monoester)Sorbitan 1.8 aggregated R = TrioleicEsters 2.1 aggregated R = Tristearic 2.7 aggregated R = Sesquioleic 14.9 no effect R = StearicFatty Acid Diethanol- amides 1-7 aggregated ##STR12## >10.0 no effect R = Coco R' = R.sup.2 = CH.sub.2 CH.sub.2 OH >10.0 no effect R = Coco R' = R.sup.2 = CH.sub.2 CH.sub.2 OHEthoxylated 5.0 aggregated R = tallow x + y = 2Tertiary 12.0 no effect R = tallow x + y = 7AminesOrganic 13-15 no effectPhosphate 13-15 no effectEstersPolyethoxylated 5.0 aggregatedand polypropoxy- 9.0 aggregatedlated polydimethyl 17.0 no effectsiloxanes__________________________________________________________________________ *aggregation: particle size > approx. 10 microns no effect: particle size < approx. 10 microns
While this invention has been described with respect to particular embodiments thereof, it is apparent that numerous other forms and modifications of this invention will be obvious to those skilled in the art. The appended claims and this invention generally should be construed to cover all such obvious forms and modifications which are within the true spirit and scope of the present invention. | A method for deinking dry toner electrostatic printed wastepaper is disclosed. The method comprises administering a sufficient amount of a surfactant with a hydrophile/lipophile balance of from about 0.5 to 10.0 to a sample of electrostatic printed wastepaper for which treatment is desired. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to refrigeration apparatus and, more particularly, to an adjustable, foldable shelf suspended from cantilevered shelf support brackets in a refrigeration apparatus.
2. Description of the Prior Art
In an effort to make the interior space of a refrigerator more usable, manufacturers have provided shelves that are either foldable to a nonuse position or removable to give maximum flexibility. Vertically adjustable cantilevered refrigerator shelves are popular because they are very versatile and attractive in appearance. While various forms of foldable shelves are known, none of them are appropriate for suspension from a glass cantilevered refrigerator shelf.
Another limitation of most foldable shelves is that they are usually limited in size, not being useful across the full width of the interior of the refrigerator cabinet. In addition, most foldable refrigerator shelves suffer from being difficult to employ and expensive to manufacture.
Pivotal suspension links for foldable shelves are shown in U.S. Pat. Nos. 2,082,672; 2,598,266; 2,808,310; and 2,146,199. However, none of these prior patents discloses a foldable shelf in which a lower shelf member can be folded up underneath an upper shelf member in a stored position and can be unfolded into a plurality of positions for various uses by means of slidable pivotal links.
SUMMARY OF THE INVENTION
The present invention provides a multiple position refrigerator shelf that can be folded to a storage position immediately under the shelf above it, to minimize wasted space when not in use, but is readily movable to a spaced, suspended use position. The invention comprehends a foldable shelf having a third position tilted towards the rear of a refrigerator for storage of wine bottles. The suspended shelf is gravity biased against the rear wall of the refrigerator liner to add stability to the shelf. Further, the folded shelf is suspended from conventional vertically adjustable cantilevered brackets in the refrigerator and is useful with either glass or wire cantilevered shelves.
The present invention provides that the multiple position shelf is substantially the same size as the shelf above it, thus filling essentially the full interior width and depth of the refrigerator compartment. Further, the invention provides for a means for retaining the shelf in a folded storage position, against the force of gravity, which is very secure and avoids the use of conventional friction latching means, such that the effectiveness of the retaining means is relatively unaffected by wear over the life of the product.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the interior of a refrigerator employing the present invention.
FIG. 2 is a partial front view of the foldable refrigerator shelf of the present invention shown in its folded position.
FIG. 3 is a side sectional view taken generally along the lines III--III of FIG. 2.
FIG. 4 is a side sectional view, similar to FIG. 3, showing the foldable shelf in a partially opened position.
FIG. 5 is a side sectional view, similar to FIG. 3, showing the complete opening movement of the foldable shelf.
FIG. 6 is a side sectional view, similar to FIG. 3, showing the foldable shelf in a locked intermediate use position.
FIG. 7 is a sectional view of the link members taken generally along the lines VII--VII of FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1, there is seen a refrigerator 10, commonly referred to as a side-by-side unit, with a refrigeration compartment 12 and a freezer compartment 14 separated by a dividing wall 15. Conventionally, the interior of refrigerator 10 is cooled by an evaporator (not shown) located in the freezer compartment and a compressor and a condenser (not shown) located in the machinery compartment 19. The refrigerator has openable doors 16 and 17 providing access to the interior of the refrigeration and freezer compartments, respectively. The refrigeration compartment is provided with a number of drawers 18 for storing food and also a plurality of vertically adjustable shelves 20. The shelves 20 are supported in cantilevered fashion by support members or ladders 22 which are secured to a rear liner wall 24 of the refrigeration compartment. A foldable shelf assembly 26 is shown in FIG. 1 and is shown in greater detail in FIGS. 2-7.
FIGS. 2 and 3 show the foldable shelf assembly 26 in the completely folded and locked position in which there is an upper glass or wire shelf member 28 supported on a pair of shelf support brackets 30, each having a projecting finger 32 at a rear end thereof which engages with the support ladder 22 such that the support bracket 30 is secured in a cantilevered position in a conventional manner.
The support brackets 30 are connected by a plurality of lateral connecting members 34 to maintain the supports in spaced parallel relationship and to add rigidity to the shelf support. A piece of front trim 36 extends across the front width of the upper shelf to provide a grasping surface for inserting the shelf and to provide a finished appearance.
A lower horizontal support surface, or shelf, 38 is movably carried on a support cradle 40. In the illustrated embodiment, shelf 38 is of wire construction but could also be made of glass. In the illustrated embodiment, cradle 40 is comprised of a pair of elongated arm members 41, each of which supports an opposite side edge of shelf 38. Arm members 41 are held in spaced parallel relationship by a plurality of cross-connecting members 42 transversely spanning the arm members 41. Wire members 43 attach to members 42 to support items placed on shelf 38. Each arm member 41 is suspended from, and is disposed directly below, one of the support brackets 30 (FIG. 7).
Hereinafter, the invention will be described in relation to one arm member 41, and associated structure, it being understood that in the preferred embodiment duplicate structure is provided to support an opposite side of shelf 38, as illustrated in FIG. 1.
Each arm member 41 has a front upstanding tab 44 and a rear upstanding tab 46. As shown in FIG. 7, the front tab 44 has a guide or pivot pin 48 extending perpendicularly therethrough at a top end thereof, the guide pin having an enlarged head 50. The guide pin is received within a slot 52 in a link member 54 which is pivotally secured at pivot pin 56 to the shelf support bracket 30. The enlarged head 50 ensures that the guide pin 48 will remain engaged within the slot 52. The slot 52 has a distal portion 58 which extends away from the pivot pin 56 toward the opposite end of the link 54. A step 60, sized to receive and retain the guide pin 48, is provided centrally along a bottom edge of the slot 52.
The rear upstanding tab 46 has a pivot pin 62 near a top end thereof to which is pivotally connected a rear link member 64. The shelf support bracket 30 has a guide or pivot pin 66 projecting therefrom which extends into a slot 68 in the rear link member 64. The guide pin 66 has an enlarged head 70 to ensure that the guide pin 66 remains engaged within the slot 68. The slot 68 is of a uniform width throughout its length.
The rear link 64 has a shoe member 72 affixed to a distal end 65 from pin 62 of the link 64. Shoe member 72 engages a fixed stop 73, which is attached to shelf support bracket 30, when the lower shelf 38 is in the folded position, shown in FIG. 3. The engagement of the shoe member 72 with fixed stop 73 prevents rotation of link member 64 about guide pin 66, thereby securely retaining or locking the lower shelf 38 in the folded storage position.
To move the lower shelf 38 to the open use position, the first step is to pull the lower shelf forwardly toward the user (or to the left as seen in FIGS. 3 and 4) until the shelf is pulled all the way out as seen in FIG. 4. During this operation, the guide pin 48 on tab 44 slides along slot 52, while link member 54 remains essentially stationary, and the link member 64 is pulled forwardly through its pivot pin 62 at tab 46 such that the link member 64 slides relative to guide pin 66. When the lower shelf 38 is pulled all of the way forward, as seen in FIG. 4, link member 64 may be pivoted about pin 66 which has moved relative to slot 68 such that it is near the distal end 65 of link member 64, and pivoting movement of link member 64 can occur without the shoe member 72 engaging stop 73.
Once the lower shelf 38 has been pulled completely forward, then it can swing downwardly as seen in FIG. 5. At this point, the link members 54, 64 pivot at each end around pins 48, 56 and 62, 66 respectively. The lower shelf 38 continues to swing downwardly until a bumper member 74 engages the rear liner wall 24 of the refrigeration compartment. The distance 76 from the rear liner wall 24 to the rear guide pin 66 attached to the shelf support bracket 30 is less than the distance 78 from the rear liner wall 24 to the pivot pin 62 secured to the rear upstanding tab 46 on the arm member 41 such that there is a continuing gravity bias downwardly and rearwardly to hold the lower shelf member 38 securely against the liner wall 24 of the refrigeration compartment, thereby stabilizing the lower shelf 38. The pins 56 and 48 have a similar relationship to the rear liner wall 24 to further aid in stabilizing the shelf member 38 against wall 24. Thus, in the use position shown in FIG. 5, the lower shelf 38 is securely held in a spaced, parallel position relative to the upper shelf 28.
In FIG. 6, the lower shelf 38 is shown in an alternative use position relative to the upper shelf member 28. In this position, the lower shelf 38 is angled upwardly toward the front of the refrigerator by means of guide pin 48 being captured within step 60 in slot 52. This angled position is convenient for storing wine bottles and other similar containers. Again, in this position, the lower shelf 38 is stably held against the rear liner wall 24 by gravity bias produced by the positioning of pins 66 and 56 on the shelf support bracket relative to pivot pins 62 and 48 on the arm member.
To refold the lower shelf 38 up to the storage position adjacent upper shelf 28, a reverse procedure of that described above is conducted. That is, the bottom shelf 38 is pivoted forwardly and upwardly to the position shown in FIG. 4 and then is slid directly back under the upper shelf to the folded and locked position of FIG. 3.
It is thus seen that a fold-down refrigerator shelf is provided which is suspended by a set of slidable pivotal link members 54, 64 in which each link member is allowed to slide along its longitudinal axis with respect to one of its pivots. The rearward link member 64 is slidable with respect to the fixed upper guide pin 66 to selectively interact with a fixed stop member 73 and the forward link member 54 is slidable with respect to the lower guide pin 48 attached to arm member 41.
As is apparent from the foregoing specification, the invention is susceptible of being embodied with various alterations and modifications which may differ particularly from those that have been described in the preceeding specification and description. It should be understood that I wish to embody within the scope of the patent warrented hereon all such modifications as reasonably and properly come within the scope of my contribution to the art. | A foldable refrigerator shelf is provided in which a lower shelf is nested directly beneath an upper shelf in a locked position and can be moved to a plurality of positions spaced from the upper shelf by means of sliding and pivoting links. The shelf is positively locked while in a folded position and is continuously biased into a stable position when in the open position. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention concerns a process for the currentless metallization of electrically non-conductive substrates on polymer base with a layer of UV hardenable lacquer, containing an organo-metallic palladium compound.
2. Description of the Related Art
Processes for the currentless metallization of electrically non-conductive substrates are known. Such a process is explained, for example, in the EP-PS 0 255 012 B1. For this process, an activator formulation containing a bonding agent is deposited on the electrically non-conductive substrate as carrier layer for the metallization. The solvent is removed from the activator formulation, which contains metal compounds in addition to bonding agents and solvents. The activator formulation is then reduced, and the substrate is metallized without current in a generally known metallization bath. The disadvantage of the known process is that the adhesion of the metallization on the substrate is not sufficient for all application cases, e.g. for the production of strip conductors with an extremely small reference grid.
SUMMARY OF THE INVENTION
In contrast, the advantage of the process according to the invention is that it is possible to obtain a metallization of extremely fine structures with high adhesiveness when the substrate is treated with UV radiation, for which the wavelength, time interval and radiation intensity can be selected, such that oxygen compounds of the polymer or the polymers develop on the substrate surface. Owing to the fact that a positive lacquer containing organic metal compounds is applied to the substrate, that the positive lacquer is subsequently irradiated with UV light and the metallization is precipitated onto the irradiated positive lacquer, it is advantageously possible to produce metallization structures with high adhesiveness, which can be reproduced in large piece numbers. The process according to the invention does not include a heat-intensive process step, so that even heat-sensitive substrates onto which the metallization is deposited can be used.
One preferred embodiment of the invention provides that the irradiation with UV light occurs at a specific wave length that can be selected and/or during a specific time interval that can be selected. The subsequent precipitating of the metallization onto the irradiated positive lacquer can be influenced advantageously through the selection of the wave length and the time interval for the irradiation. The metallization can thus be adjusted in such a way that an intermediate metal oxide layer is deposited first, on which the actual metallization then builds up. In this way, a high adhesiveness of the metallization on the substrate is achieved without requiring an additional intermediate step, meaning the intermediate layer and the main layer are precipitated during one operation. Metallization layers that adhere particularly well can be produced on the substrate, especially with use of a short-wave UV light according to the invention.
Another preferred embodiment of the invention provides that electrical strip conductors are produced through metallization in a copper bath. Owing to the high adhesiveness of the metallizations on the substrate, it is possible to produce extremely complex circuits, which can have a high cross-linkage in a small space. A distance between two strip conductors can be kept very small. It is furthermore preferable if electrical resistors are produced through metallization in a nickel or nickel-alloy bath. It is easy to produce highly adhesive electrical resistors in circuit arrangements with this method, which can be incorporated in the total production process for a printed circuit board by using a process step that is easily mastered.
Further advantageous embodiments of the invention follow from the remaining features specified in the dependent claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained in the following in more detail with the embodiments and the associated drawings. Shown in:
FIG. 1 is a flow chart of the process sequence according to the invention;
FIG. 2 is a reaction sequence for fixing the positive lacquer during the irradiation with UV light and
FIG. 3 are various examples for the use of organic metal compounds in the positive lacquer.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is intended to illustrate the process according to the invention with the aid of a diagram. In a first process step 10, an electrically non-conductive substrate is provided with a carrier layer for the metallization that is still to be explained. Any optional organic or inorganic molded article, which can have a rigid as well as a flexible design, can be used as substrate.
A polyimide foil (Kapton) is used according to a concrete exemplary embodiment. The positive lacquer can be applied to the substrate with generally known process steps, e.g. through spraying on, painting on, rolling on, offset print, screen print, tampon print (gravure printing), dipping, etc. It is not necessary to prepare the substrate prior to applying the positive lacquer. Depending on the process for applying it to the substrate, the positive lacquer has a composition that is specially adjusted to this process. This concerns, for example, the solvents contained in the positive lacquer, which must be selected differently for the tampon print than for the screen print, owing to the varied technological sequence. The positive lacquer furthermore contains organic metal compounds, which serve as activators (germinating cells) for the subsequent metallization.
In accordance with a concrete embodiment, soluble palladium compounds are used as organic metal compounds in organic solvents. These can be the compounds having the chemical formulas as shown in FIG. 3, for example.
The following can be used as palladium compounds:
______________________________________according to a) palladium acetylacetonate (R═CH.sub.3) and phenyl derivative (R═C.sub.6 H.sub.5);according to b) palladium glyoximate;according to c) dichloro(1,3-butadienyl)palladium (II);according to d) dichlorocyclooctadienyl-(1,5)-palladium (II)according to e) dichlorobis-(acetonitrile)palladium (II);according to f) π allyl complex andaccording to g) tetrakis-(triphenylphosphine)palladium (O).______________________________________
This positive lacquer containing the palladium compounds and solvents, bonding agents, coloring agents etc, which will not be examined in more detail here, is applied to the substrate with a layout that can be selected. In this case, the lacquer can be applied to the substrate surface either over a large region or to selective locations. A positive lacquer within the meaning of the invention is understood to be a lacquer containing light-active components that effect a chemical change in the positive lacquer composition under the influence of light.
The substrate coated with the positive lacquer is irradiated in a subsequent process step 12 with light from an UV light source. The irradiation with the UV light triggers a reaction in the positive lacquer, which is illustrated with the aid of FIG. 2. The light-active component of the positive lacquer is a diazoketone, for example, which forms a ketene when irradiated with UV light by separating out nitrogen in accordance with the so-called Wolf rearrangement. This ketene then stabilizes based on the Arndt-Eistert Reaction in the presence of humidity (H 2 O) by forming a carboxylic acid. The palladium compound contained in the positive lacquer as activator is fixed during the here occurring complexation reaction. Following irradiation with the UV light, the positive lacquer together with the palladium compound results in a stable compound that is fixed well on the substrate surface. Illuminating the positive lacquer with the UV light results in the formation of oxygen compounds, which have a decisive effect on the subsequent metallization.
The illumination with the UV light can be varied for coordination with the subsequent metallization. Thus, it is possible to select for the UV light illumination a time interval and/or a UV light with an optional wavelength. Based on a concrete embodiment, for example, an illumination with a UV light source lasts for 10 minutes at an irradiation of 15 . . . 150 mW/cm 2 and has wavelengths that are coordinated with the total lacquer system, including the palladium components. Wavelengths of 222, 308, 356 and 400 nm, for example, are suitable. It is possible to influence the formation of the oxygen compounds on the surface of the substrate by varying the irradiation, the wavelength of the UV light and the treatment duration. A varied metallization of the substrate results, depending on the number and type of existing oxygen compounds.
The substrate surface coated with the palladium compounds is subjected in a subsequent process step 14 to a reduction. For this, the substrate is dipped into a reduction bath, for example, preferably a NaBH 4 solution, so that the palladium compounds present in an oxidation stage are reduced and a zerovalent palladium is subsequently present. The oxygen compounds on the substrate surface are not changed during this process step.
During a final process step 16, the substrate is placed into a metallization bath. The metallization bath can, for example, be a copper bath. In that case, the substrate regions previously coated with the palladium-containing positive lacquer are copper-plated without current. A currentless copperplating takes place in the copper bath in that copper precipitated from the copper bath reacts with the positive lacquer that is irradiated with the UV light. The copper in this case combines with the oxygen compounds present on the substrate surface to form initially copper oxide CuO, which is deposited on the substrate surface. This copper oxide forms an intermediate layer, which functions to promote adhesion between the substrate and the subsequent actual metallization. Once the free oxygen compounds on the substrate surface are used up for the copper oxide layer formation, pure metallic copper is deposited there. Thus, the precipitating of an adhesive layer and the precipitating of the actual metallization layer occur simultaneously during one process step. As a result, the metallization layer adheres extremely well to the substrate. Depending on the selected layout, with which the positive lacquer enriched with the palladium compounds was deposited on the substrate, the substrates can be provided with strip conductors or larger metallization regions (copper in this case) with an optional geometry. For example, it is possible to obtain strip conductors that adhere extremely well, e.g. with a width of 65 μm or smaller, a thickness of 2 . . . 3 μm and also a spacing between them of 65 μm or smaller. As a result of the excellent adhesion of the metallization, it is possible to achieve a high quality for these small reference grids. A galvanic strengthening of the strip conductors owing to a subsequent galvanic depositing of copper can be achieved if necessary.
According to another embodiment, a nickel or nickel-alloy bath, for example, can be used in place of the copper bath. By doing this, metallization layers of nickel or nickel alloy can be realized on the substrate, which can be integrated favorably into existing circuit arrangements as electrical resistance layers.
Owing to a quite favorable combination of the treatment for the substrates, it is possible to create circuit arrangements having electrical strip conductors as well as electrical resistors. It is possible, for example, to initially structure strip conductors on the substrate and subsequently provide the respective resistance layers by combining or repeating the sequence of the individual process steps. For this, the palladium-containing positive lacquer can be applied several times to the substrate, meaning that after the positive lacquer is applied for the first time, is illuminated with UV light and copper-plated in a copper bath, another layer of palladium-containing positive lacquer can be applied in a following process step to the substrate that already has strip conductors. This layer is then correspondingly illuminated and provided with the resistance layers.
The coating of the substrate with copper or nickel or nickel alloys is only an example. Thus, a metallization with any other suitable metal is of course possible as well. On the whole, it is critical for the process according to the invention that all process steps are performed at room temperature, so that no allowances have to be made for heat-sensitive substrates. However, it is quite possible to perform individual process steps also at higher temperatures. Furthermore, additional heat sources, e.g. for heating up the metallization baths and/or for applying the positive lacquer layer, are not necessary, so that energy can be saved as compared to traditional processes. Extremely fine and highly adhesive structures can be obtained with the process according to the invention for the currentless metallization. In particular the successive depositing of the adhesive layer and the actual metallization layer in one process step result in excellent adhesion values for the metallization on the substrate. | A process for the currentless metallization of electrically non-conductive substrates, includes providing a substrate which is electrically non-conductive; depositing on the substrate a positive lacquer comprising at least one polymer which is UV hardenable, at least one organo-metalllic compound, and a substance which is light-active to provide a positive lacquer coated substrate; irradiating the positive lacquer coated substrate with UV radiation to provide an irradiated coated substrate; and precipitating a metal layer onto the irradiated coated substrate by currentless metallization in a bath effective therefore. | 2 |
TECHNICAL FIELD
The present invention relates to a process for producing a β-amino-α-hydroxy acid derivative by the hydrolysis, in the presence of a base, of an α-amino-α', α'-dihaloketone derivative derived from the corresponding α-amino acid. More minutely, the present invention relates to a process for producing an optically active β-amino-α-hydroxycarboxylic acid derivative which comprises deriving an optically active α-amino acid, such as L-phenylalanine, into an α-amino-α', α'-dihaloketone derivative and then hydrolyzing the latter in the presence of a base, in particular to a process for producing a β-amino-α-hydroxycarboxylic acid derivative having the so-called erythro configuration. The "erythro configuration" herein indicates that the a -hydroxy and β-amino groups show the following relative arrangement: ##STR2##
BACKGROUND ART
Among the so-far known processes for producing an optically active β-amino-α-hydroxycarboxylic acid derivative, there may be mentioned, for instance, the process comprising cyanizing an N-protected phenyl-alaninal derivative and then hydrolyzing the resultant derivative ((1) Synthesis, 1989, page 709; (2) Journal of Medicinal Chemistry, vol. 37, page 2918, 1994; (3) Journal of Medicinal Chemistry, vol. 20, page 510, 1977).
However, the process comprising cyanizing an N-protected phenylalaninal derivative and then hydrolyzing the resultant derivative is not suited for the production of an erythro-form β-amino-α-hydroxy acid derivative since the stereoselectivity is of the so-called threo-selective type or almost no stereoselectivity is found. It has a problem in that the use of a strongly toxic cyanizing agent is required. Said threo configuration indicates a relative configuration opposite to the erythro configuration mentioned above.
A process is also known which comprises stereoselectively adding N-benzyl-α-phenethylamine to α, β-unsaturated esters in the manner of Michael addition, followed by hydroxylation (Synlett, vol. 10, page 731, 1993), for instance. However, it has a problem in that not less than equivalent amounts of the optically active amine and oxidizing agent have to be used.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a process for producing a β-amino-α-hydroxy acid derivative via steps feasible efficiently and industrially.
The gist of the present invention lies in that a βamino-α-hydroxy acid derivative of the general formula (2): ##STR3## (wherein R 1 represents a substituted or unsubstituted alkyl group containing 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group containing 7 to 30 carbon atoms, or a substituted or unsubstituted aryl group containing 6 to 30 carbon atoms; Q 1 and Q 2 each independently represents a hydrogen atom or an amino-protecting group or Q 1 and Q 2 combinedly represent a phthaloyl group) is produced by hydrolyzing an α-amino-α', α'-dihaloketone derivative of the general formula (1): ##STR4## (wherein R 1 is as defined above; X 1 and X 2 each independently represents a halogen atom; P 1 and P 2 each independently represents a hydrogen atom or an amino-protecting group or P 1 and P 2 combinedly represent a phthaloyl group) in the presence of a base, followed by protecting the amino group or without protecting the same.
In another aspect, the gist of the present invention also consists in that the β-amino-α-hydroxy acid derivative of the general formula (2) given above is produced by treating an α-amino-α'-monohaloketone derivative of the general formula (3) ##STR5## (wherein R 1 represents a substituted or unsubstituted alkyl group containing 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group containing 7 to 30 carbon atoms, or a substituted or unsubstituted aryl group containing 6 to 30 carbon atoms; X 1 represents a halogen atom; P 1 and P 2 each independently represents a hydrogen atom or an amino-protecting group or P 1 and P 2 combinedly represent a phthaloyl group) with a halogenating agent to give an α-amino-α', α'-dihaloketone derivative of the general formula (1) given above and then hydrolyzing the resultant derivative in the presence of a base, followed by protecting the amino group or without protecting the same.
The gist of the present invention further lies in that the β-amino-α-hydroxy acid derivative of the general formula (2) given above is produced by converting an α-amino acid derivative of the general formula (4): ##STR6## (wherein R 1 represents a substituted or unsubstituted alkyl group containing 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group containing 7 to 30 carbon atoms, or a substituted or unsubstituted aryl group containing 6 to 30 carbon atoms; R 2 represents a substituted or unsubstituted alkyl group containing 1 to 10 carbon atoms, a substituted or unsubstituted aralkyl group containing 6 to 15 carbon atoms, a substituted or unsubstituted aryl group containing 7 to 21 carbon atoms, or a hydrogen atom; P 1 and P 2 each independently represents a hydrogen atom or an amino-protecting group or P 1 and P 2 combinedly represent a phthaloyl group) to an α-amino-α-monohaloketone derivative of the general formula (3) given above, further treating the resultant derivative with a halogenating agent to give an α-amino-α', α'-dihaloketone derivative of the general formula (1) given above and further hydrolyzing the same in the presence of a base, followed by protecting the amino group or without protecting the same.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is now described in further detail.
The α-amino-α', α'-dihaloketone derivative, which is used in the practice of the present invention is a compound of the general formula (1) given above. The above-mentioned R 1 represents a substituted or unsubstituted alkyl group containing 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group containing 7 to 30 carbon atoms, or a substituted or unsubstituted aryl group containing 6 to 30 carbon atoms.
Said substituted or unsubstituted alkyl group containing 1 to 20 carbon atoms is not limited to any particular species but there may be mentioned, for example, methyl, ethyl, isopropyl, isobutyl, t-butyl, hydroxymethyl, 1-hydroxyethyl, mercaptomethyl, methylthiomethyl and the like.
The above-mentioned substituted or unsubstituted aralkyl group containing 7 to 30 carbon atoms is not limited to any particular species but includes, for example, benzyl, p-hydroxybenzyl, p-methoxybenzyl, phenylthiomethyl, α-phenethyl and the like.
The above-mentioned substituted or unsubstituted aryl group containing 6 to 30 carbon atoms is not limited to any particular species but includes, for example, phenyl, p-hydroxyphenyl, p-methoxyphenyl and the like.
The above-mentioned R 1 is the side chain of a common α-amino acid or the side chain of an α-amino acid derivative obtained by processing a common α-amino acid and may be any of substituted or unsubstituted alkyl groups containing 1 to 20 carbon atoms, substituted or unsubstituted aralkyl groups containing 7 to 30 carbon atoms and substituted or unsubstituted aryl groups containing 6 to 30 carbon atoms, without any particular limitation.
The above-mentioned P 1 and P 2 each independently represents a hydrogen atom or an amino-protecting group or P 1 and P 2 combinedly represent a phthaloyl group. The case in which each of P 1 and P 2 is a hydrogen atom is also included.
The amino-protecting group mentioned above is not limited to any particular species but there may be mentioned, for example, ethoxycarbonyl, methoxy-carbonyl, t-butoxycarbonyl, benzyloxycarbonyl, acetyl, trifluoroacetyl, benzyl, dibenzyl, tosyl, benzoyl, phthaloyl and the like, as described in Theodora W. Green: Protective Group In Organic Synthesis, 2nd Edition, JOHN WILEY & SONS, 1990, pages 309 to 384.
While the protective group mentioned above is selected taking into consideration of the reactivity and stereoselectivity in each step and other factors, there may be mentioned, as most preferred protective groups to be used in the synthesis of each compound represented by the general formula (4), (3), (1) or (2) mentioned above, ethoxycarbonyl, methoxycarbonyl, t-butoxycarbonyl, benzyloxycarbonyl and the like carbamate-forming groups, in particular ethoxycarbonyl. Carbamate-forming groups such as ethoxycarbonyl generally tend to preferentially give erythro stereoisomers, which are useful as an intermediate for HIV protease inhibitors, in the stage of the formation of compounds of general formula (2) from compounds of general formula (1).
The above-mentioned X 1 and X 2 each represents a halogen atom, such as fluorine, chlorine, bromine or iodine. It is preferred that each of X 1 and X 2 be chlorine.
As the above-mentioned α-amino-α', α'-dihalo-ketone derivative of general formula (1), there may be mentioned, for example, optically active ethyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, ethyl (R)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, methyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)-carbamate, methyl (R)-(l-benzyl-3,3-dichloro-2-oxopropyl)carbamate, benzyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, benzyl (R)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, t-butyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, t-butyl (R)-(1-benzyl-3,3-dichloro-2-oxopropyl)-carbamate, ethyl (S)-(1-phenyl-3,3-dichloro-2-oxopropyl)carbamate, ethyl (R)-(1-phenyl-3,3-dichloro-2-oxopropyl)carbamate, ethyl (S)-(1-benzyl-3,3-dibromo-2-oxopropyl)carbamate, ethyl (R)-(1-benzyl-3,3-dibromo-2-oxopropyl)carbamate, ethyl (S)-(1-benzyl-3,3-dibromo-2-oxopropyl)carbamate, ethyl (S)-(1-phenyl-3,3-dichloro-2-oxopropyl)carbamate, N-(3,3-dichloro-1-methylacetonyl)phthalimide, 3-(N,N-dibenzylamino)-1,1-dichloro-2-oxo-4-phenylbutane and the like. Among these, some compounds, such as N-(3,3-dichloro-1-methylacetonyl)-phthalimide, are already known (Spisy Prirodoved. Fak. Univ. J. E. Purkyne Brne, (1968), No. 489, 1 to 7). However, an α-amino-α', α'-dichloroketone derivative of the general formula (5): ##STR7## (wherein R 1 represents a substituted or unsubstituted alkyl group containing 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group containing 7 to 30 carbon atoms or a substituted or unsubstituted aryl group containing 6 to 30 carbon atoms and R 3 represents a substituted or unsubstituted alkyl group containing 1 to 10 carbon atoms, a substituted or unsubstituted aralkyl group containing 7 to 20 carbon atoms or a substituted or unsubstituted aryl group containing 6 to 20 carbon atoms), in particular an α-amino-α', α'-dichloroketone derivative of the general formula (6): ##STR8## (wherein R 3 represents a substituted or unsubstituted alkyl group containing 1 to 10 carbon atoms, a substituted or unsubstituted aralkyl group containing 7 to 20 carbon atoms or a substituted or unsubstituted aryl group containing 6 to 20 carbon atoms) are novel compounds for which the method of production as well as the compounds themselves has not yet been described in the literature.
Referring to R 3 in the above general formula (5), the substituted or unsubstituted alkyl group containing 1 to 10 carbon atoms is, for example, methyl, ethyl, isopropyl, isobutyl, t-butyl or allyl, the substituted or unsubstituted aralkyl group containing 7 to 20 carbon atoms is benzyl, p-methoxybenzyl, p-nitrobenzyl or the like, and the substituted or unsubstituted aryl group containing 6 to 20 carbon atoms is phenyl, m-nitrophenyl or the like.
As the above-mentioned compound of general formula (5), there may be mentioned, for example, ethyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, ethyl (R)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, methyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, methyl (R)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, benzyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, benzyl (R)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, t-butyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, t-butyl (R)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, ethyl (S)-(1-phenyl-3,3-dichloro-2-oxopropyl)carbamate, ethyl (R)-(1-phenylphenyl-3,3-dichloro-2-oxopropyl)carbamate, ethyl (S)-(1-benzyl-3,3-dibromo-2-oxopropyl)carbamate, ethyl (R)-(1-benzyl-3,3-dibromo-2-oxopropyl)carbamate, ethyl (S)-(1-methyl-3,3-dichloro-2-oxopropyl)carbamate, ethyl (S)-(1-phenylisobutyl-3,3-dichloro-2-oxopropyl)carbamate, ethyl (S)-(1-phenylisopropyl-3,3-dichloro-2-oxopropyl)-carbamate, etc.
As the above-mentioned compound of general formula (6), there may be mentioned, for example, ethyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, ethyl (R)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, methyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, methyl (R)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, benzyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, benzyl (R)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, t-butyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, t-butyl (R)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, etc.
The hydrolysis reaction of the above-mentioned α-amino-α', α'-dihaloketone derivative in the presence of a base is preferably carried out in water or a mixed solvent composed of water and an organic solvent in the presence of a base.
Said organic solvent is not limited to any particular species but there may be mentioned, for example, of toluene, chlorobenzene, benzene, methylene chloride, methanol, ethanol, n-butanol, tetrahydrofuran, N,N-dimethylformamide and the like. Toluene, chlorobenzene and benzene are preferred, and toluene is more preferred.
Said base is not limited to any particular species but there may be mentioned, for example, of sodium hydroxide, potassium hydroxide, lithium hydroxide, barium hydroxide, magnesium hydroxide, calcium hydroxide, sodium carbonate, potassium carbonate, tetra-n-butylammonium hydroxide, tetramethylammonium hydroxide, trimethylbenzylammonium hydroxide, tetra-n-butylammonium hydroxide and the like. Sodium hydroxide is preferred, however.
While the reaction temperature in the above reaction may vary depending on the combination of substrate, solvent and base and other factors, the range of -30 to 100° C. is preferred and the range of -10 to 60° C. is more preferred. The reaction temperature influences the stereoselectivity and rate of reaction in the hydrolysis reaction. In the case of ethyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate, for instance, lower temperatures tend to cause a decrease in the rate of reaction but an increase in erythro selectivity.
The reaction time may vary depending on the combination of substrate and base, the reaction temperature and other factors. Generally, however, 1 to 80 hours is preferred, and 3 to 20 hours is more preferred.
In the above-mentioned compound of general formula (2), Q 1 and Q 2 each independently represents a hydrogen atom or an amino-protecting group or Q 1 and Q 2 combinedly represent a phthaloyl group. When the compound of general formula (1) is hydrolyzed in the presence of a base, the amino group, if protected, may be deprotected or not be deprotected according to the combination of reaction conditions and protective group species. In the case of the hydrolysis of ethyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)carbamate in an aqueous solution of sodium hydroxide, for instance, the amino deprotection tends to occur with ease. In this case, an oxazolidone derivative of the formula (7): ##STR9## may be formed as a reaction intermediate. The resultant derivative , however, can be converted to a β-amino-α-hydroxy derivative of the general formula (2) given above in which R 1 is benzyl and Q 1 and Q 2 each is a hydrogen atom by further hydrolyzing under the reaction conditions. In cases where deprotection occurs in the reaction system, the product may be isolated in a protective group-free state or a new protective group may be introduced. Therefore, Q 1 and Q 2 each represents a hydrogen atom, or the same protective group as P 1 and P 2 , or a protective group newly introduced. Like P 1 and/or P 2 , the group to be newly introduced is not limited to any particular species provided that it is a protective group generally used as an amino-protecting group. A t-butoxycarbonyl group is preferred, however.
In cases that a protective group is newly introduced, it is also possible, for example, to isolate the product of hydrolysis of the above-mentioned compound of general formula (1) by using a purification technique commonly used in isolating α-amino acids, such as crystallization or purification with an ion exchange resin, and then subject it to an amino group protection reaction, or subject the α-amino hydroxy acid in the aqueous layer, without isolation, to an amino group protection reaction.
When the above-mentioned compound of general formula (1) is subjected to said hydrolysis reaction, it is possible for the product to have any of four configurations. However, in cases where an optically active α-amino-α', α'-dihaloketone derivative such as ethyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl)-carbamate is used, it is surprising that racemization hardly proceeds and there is a tendency toward preferential formation of the erythro form of the two diastereomers that can possibly be formed. As a so-far known method of producing an α-hydroxy acid by alkali hydrolysis of an α-dihaloketone, there may be mentioned the method of producing mandelic acid using α-dichloroacetophenone (Organic Syntheses, Collective Volume 3, page 538), for instance. However, no technology has been known for producing an α-hydroxy acid derivative from an α', α'-dihaloketone having an optically active site in the a position of a carbonyl group with retaining the optical activity and stereoselectively.
The above-mentioned compound of general formula (1) can be produced by various methods. For instance, it can be produced by halogenating an α-amino-α'-monohaloketone derivative of the general formula (3): ##STR10## (wherein R 1 , X 1 , P 1 and P 2 are as defined above). The halogenating agent is not limited to any particular species but sulfuryl chloride or chlorine/carbon tetrachloride, for instance, may be used (Synthetic Communication, vol. 21, No. 1, page 111, 1991). From the viewpoint of economy and operability, among others, sulfuryl chloride is preferred.
The above-mentioned compound of general formula (3) can be produced by various methods. For Instance, it can be produced by converting an α-amino acid derivative of the general formula (4): ##STR11## (wherein R 2 , P 1 and P 2 are as defined above). As for the method of conversion, It can be produced, for instance, by reacting an ester derivative with the magnesium enolate of α-chloroacetic acid or the like (Japanese Patent Application Hei-07-273547).
(2S,3S)-3-[(t-butoxycarbonyl)amino]-2-hydroxy-4-phenylbutyric acid produced by the process of the present invention is a compound useful as an intermediate for the production of an HIV protease inhibitor (Japanese Kokai Publication Hei-05-170722).
BEST MODES FOR CARRYING OUT THE INVENTION
The following examples illustrate the present invention in further detail. They are, however, by no means limitative of the scope of the present invention.
EXAMPLE 1
Production of ethyl (S)-(1-benzyl-3-chloro-2-oxo-propyl)carbamate (I) ##STR12##
In a nitrogen gas atmosphere, a solution composed of (S)-N-(ethoxycarbonyl)phenylalanine methyl ester (35.0 g, 139 mmol), sodium monochloroacetate (24.2 g, 208 mmol), magnesium chloride (19.9 g, 208 mmol) and tetrahydrofuran (125 ml) was stirred at 40° C. for 3 hours (solution A). Separately, in a nitrogen atmosphere, diisopropylamine (65.0 g, 642 mmol) was added dropwise at 40° C. over 30 minutes to n-butylmagnesium chloride (2 M THF solution, 278 ml, 556 mmol) and the resulting mixture was further stirred at 40° C. for 2 hours (solution B). Solution B was added at about 10° C. (inside temperature) over about 30 minutes to solution A. After completion of the addition, the inside temperature was raised to 40° C. and stirring was continued for further 2 hours. Then, the reaction mixture was mixed with 900 ml of an ice-cooled mixed solution composed of 10% (w/v) aqueous solution of sulfuric acid and 550 ml of ethyl acetate with stirring. After thorough mixing, the mixture was allowed to separate into layers. The organic layer was washed in sequence with a saturated aqueous solution of sodium hydrogen carbonate (300 ml) and a saturated solution of sodium chloride (300 ml) and then dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, 30 ml of isopropanol was added to the residue, the mixture was heated to 60 to effect dissolution, 600 ml of hexane was then added, and the mixture was gradually cooled to 5° C. for allowing crystallization. The precipitate crystals were collected by filtration, washed with hexane and dried under reduced pressure to give 28.5 g of white needle crystals. 1 H NMR (400 MHz, CDCl 3 ): δ7.35 to 7.16 (m, 5H), 5.17 (d, 1H), 4.75 (q, 1H), 4.17 to 4.08 (m, 2H), 4.00 to 3.96 (ds, 2H), 3.09 to 3.07 (m, 2H), 1.23 (t, 3H)
EXAMPLE 2
Production of ethyl (S)-(1-benzyl-3,3-dichloro-2-oxopropyl) carbamate (II) ##STR13##
The compound (I) obtained in Example 1 (25.0 g, 92.7 mmol) was dissolved in ethyl acetate (250 ml), and sulfuryl chloride (38.8 g, 287 mmol) and p-toluenesulfonyl chloride monohydrate (1.8 g, 9.5 mmol) were added, and the mixture was stirred at 45° C. for 40 hours. The reaction mixture was cooled to room temperature and added to a solution composed of water (150 ml) and toluene (200 ml) while the pH was adjusted to about 3 with a 2 M aqueous solution of sodium hydroxide. After thorough stirring, the organic layer was separated and concentrated to a volume of about 50 ml. That toluene solution was warmed to 60° C., hexane (300 ml) was added, and the mixture was gradually cooled to 5° C. for allowing crystallization. The crystals were collected by filtration, washed with hexane and dried under reduced pressure to give compound (II) (22.8 g, 75.0 mmol). 1 H NMR (400 MHz, CDCl 3 ): δ7.36 to 7.18 (m, 5H), 6.05 (s, 1H), 5.09 (d, 1H), 4.95 (q, 1H), 4.12 to 4.07 (q, 2H), 3.24 to 3.19 (dd, 1H), 3.07 to 3.02 (dd, 1H), 1.22 (t, 3H). IR (KBr): 3450, 1746, 1690, 1551, 1266, 1048 cm -1 .
EXAMPLE 3
Production of (2RS,3S)-3-amino-2-hydroxy-4-phenyl-butyric acid (III) ##STR14##
Toluene (120 ml) and a 2 M aqueous solution of sodium hydroxide (120 ml) were added to the compound (II) obtained in Example 2 (15 g, 49.3 mmol), and the mixture was stirred at 40° C. for 48 hours. The reaction mixture was allowed to cool to room temperature, and the aqueous layer was separated. This aqueous layer was adjusted to pH 7 and then passed through a column packed with 600 cm 3 of a synthetic adsorbent (Diaion SP207, product of Mitsubishi Chemical Corp.), the column was washed with water and elution was effected with 50% methanol. The eluate was concentrated to give the compound (III) (8.3 g, 86%).
Analysis of the compound (III) obtained by HPLC revealed that the proportion of the (2S,3S) isomer to the (2R,3S) isomer was 84:16. For (2S,3S) isomer; 1H NMR (400 MHz, D 2 O): δ7.25 to 7.13 (m, 5H), 4.10 (d, 1H), 3.66 (m, 1H), 2.79 to 2.76 (ddd, 1H), 2.70 to 2.64 (ddd, 1H). For (2R,3S) isomer; H NMR (400 MHz, D 2 O): δ7.25to 7.13 (m, 5H), 3.87 (d, 1H), 3.61 (m, 1H), 3.00 to 2.95 (dd, 1H), 2.79 to 2.76 (ddd, 1H).
EXAMPLE 4
Production of (2RS,3S)-3-amino-2-hydroxy-4-phenyl-butyric acid (III)
The compound (II) (5.0 g, 16.4 mmol) was added to a 2 M aqueous solution of sodium hydroxide (50 ml) under ice cooling, and the mixture was stirred at 0° C. for 3 hours. Thereafter, the temperature was raised to 40° C. and stirring was continued for further 6 hours. The reaction mixture was allowed to cool to room temperature and then adjusted to pH 7 with 2 M aqueous hydrochloric acid. The thus-treated reaction mixture was passed through a 200 cm 3 column of a synthetic adsorbent (Diaion SP207, product of Mitsubishi Chemical Corp.), the column was washed with water and elution was effected with 50% aqueous methanol. The eluate was concentrated to give the compound (III) (2.6 g, 82%). Analysis of the compound (III) obtained by HPLC revealed that the proportion of the (2S,3S) isomer to the (2R,3S) isomer was 90:10.
EXAMPLE 5
Production of (2S,3S)-3-[(t-butoxycarbonyl)-amino]-2-hydroxy-4-phenylbutyric acid (IV) ##STR15##
The reaction was carried out in the same manner as in Example 3. The aqueous solution of (2RS,3S)-3-amino-2-hydroxy-4-phenylbutyric acid (III) (4.69 g, 24.0 mmol, erythro/threo=84/16) as obtained without synthetic adsorbent treatment was adjusted to pH 9 by adding 1 N aqueous NaOH and, after addition of 17.6 ml of THF, the mixed solution was cooled to an inside temperature not higher than 10° C.
After addition of sodium carbonate (3.35 g, 31.6 mmol) to the mixed solution, di-t-butyl dicarbonate (6.94 g, 31.8 mmol) was added dropwise. After completion of the dropping, the reaction mixture was stirred at room temperature for 8 hours. The reaction mixture was diluted with 120 ml of ethyl acetate and adjusted to pH 2 with 6 N hydrochloric acid, followed by phase separation.
The organic layer was washed with 50 ml of 10% citric acid and concentrated under reduced pressure to give a pale yellow solid. Acetonitrile (50 ml) was added and the mixture was heated to effect dissolution and then cooled to give 3.15 g (10.7 mmol, yield 44%) of the title compound as white crystals. 1 H NMR (400 MHz, DMSO-d 6 ): δ7.24 to 7.16 (m, 5H), 6.71 (d, 1H), 3.99 (d, 1H), 3.91 (m, 1H), 2.67 (d, 2H), 1.26 (s, 7H), 1.14 (s, 2H).
The result that the title compound obtained was in a (2S,3S) form was confirmed by converting to the corresponding methyl ester, followed by HPLC analysis on an optical dissolution column. Analysis: retention time in HPLC: (2S,3S) form 20.1 minutes, (2R,3R) form 21.9 minutes.
The HPLC analysis was performed under the following conditions: Column: DAICEL Chiralcel ODH 4.6 mm ID×250 mm (Daicel Chemical Industries) Eluant: hexane/i-propanol=98/2; Rate of flow: 1.0 ml/min.; Temperature: 40° C.; Detection wavelength: 210 nm.
EXAMPLE 6
Production of (2RS,3S)-3-[(p-toluenesulfonyl)-amino]-2-hydroxy-4-phenylbutyric acid (V) ##STR16##
3-[(p-toluenesulfonyl)-amino]-1,1-dichloro-2-oxo-4-phenylbutane (55.6 mg, 0.1444 mmol) was dissolved in 3 ml of toluene, and an aqueous solution of sodium hydroxide (89 mg) in water (3 ml) was added while cooling the aqueous solution to 10° C. or below (inside temperature). After completion of the addition, the temperature of the reaction mixture was gradually raised to room temperature and the mixture was stirred for 19 hours.
Water (5 ml) and toluene (5 ml) were added to the reaction mixture, followed by phase separation. The aqueous layer was diluted with 10 ml of ethyl acetate and the pH was adjusted to 2 with 6 N hydrochloric acid, followed by phase separation. The organic layer was washed with 3 ml of 10% citric acid and concentrated under reduced pressure to give the title compound (V) as a roughly purified pale yellow oil (69 mg).
Analysis of the thus-obtained product (V) by HPLC revealed that the proportion of the (2S,3S) isomer to the (2R,3S) isomer was 70:30. For (2S,3S) isomer; 1 H NMR (400 MHz, CDCl 3 ): δ7.40 to 6.86 (m, 9H), 5.90 (d, 1H), 4.58 (d, 1H), 3.79 (m, 1H), 2.86 to 2.52 (m, 2H), 2.34 (s, 3H). For (2R,3S) isomer; 1 H NMR (400 MHz, CDCl 3 ): δ7.40 to 6.86 (m, 9H), 5.95 (d, 1H), 4.12 (d, 1H), 3.90 (m, 1H), 2.86 to 2.52 (m, 2H), 2.38 (s, 3H).
INDUSTRIAL APPLICABILITY
A (2S,3S)-3-amino-2-hydroxy-4-phenylbutyric acid derivative obtained by the production process of the present invention is a compound which is important as an intermediate for the production of medicinals such as antivirus agents and therefore, the present invention is very useful as a process for producing intermediates for the production of medicinals. | An object of the present invention is to provide a process for producing a β-amino-α-hydroxy acid derivative via efficient and industrially utilizable steps.
The present invention provides a process for producing a β-amino-α-hydroxy acid derivative represented by the general formula (2) given below which comprises hydrolyzing an α-amino-α', α'-dihaloketone derivative of the general formula (1) given below in the presence of a base, followed by protecting the amino group or without protecting the same. ##STR1## | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention pertains to the field of forming splined surfaces particularly on sheet metal components and more particularly to producing splines having shallow pressure angles produced by successive passes through forming dies.
2. Description of the Prior Art
Currently automatic transmissions have heavy cast or forged clutch and brake cylinders formed with splines on their outer surfaces. The splines permit axial movement in a guided relationship upon being pressurized by the hydraulic system of the transmission. The clutch and brake cylinders have walls that are thick and strong enough so that internal and external splines can be machined on their cylindrical surfaces. Lighter weight clutch and brake cylinders for an automatic transmission could be made if the splines could be formed by cold working processes such as by drawing the spline contour on sheet metal cups. Accurately controlled spline contours must be produced by the process for use in an automatic transmission, however.
It is a requirement, particularly in automatic transmission applications of a sheet metal splined cylinder, that the pressure angle be kept low and the corner radii of the splines be fairly tight. In this way, reliable positive engagement between internal and external meshing splines can be assured. If the pressure angle is too shallow, the height of the splines must be made correspondingly greater in order to maintain the contact pressures produced by the torque being transmitted between the splines at an acceptable level. This is a particularly important problem when the splined surfaces are formed on sheet metal whose dimensional stability under the radial loads produced by the torque is considerably less than that of the conventional cast or forged clutch and brake cylinders.
SUMMARY OF THE INVENTION
The process for forming dimensionally precise external and internal splines on a preformed sheet metal cup according to this invention produces parts that are lightweight and dimensionally accurate. The sheet metal thicknesses, which are closely controlled, may vary at selected portions of the spline contour. Splines can be formed in high volume by a simple drawing operation that can be automated to minimize labor costs. It is a further object of this invention that the splines so formed be made without machining.
The method according to this invention forms longitudinal splines on the peripheral surface of a cup made from a sheet metal blank in the form of a circular disc. A die having a splined inner surface that is conjugate and complementary to the outer spline surface of a male punch is arranged to permit the sheet metal to be located in an annular space provided between the surfaces as the punch is moved within the die. In this way, the disc attains a generally cylindrical configuration having internal and external splines defined by the annular space provided between the contours of the punch and of the die. This annular space has a radial dimension that is less than the thickness of the sheet. Accordingly, the metal forming the circumferential length of the disk near its outer diameter that would otherwise exceed the circumferential length of the cylinder is displaced longitudinally to produce a somewhat increased length spline. The thickness of the cylinder can be closely controlled by the radial dimension of the annular space.
Another aspect of this invention provides for a sheet metal cylinder, whose spline contour has a shallow pressure angle and tight bend radii at the corners of the spline to be formed in a drawing operation that includes at least two passes. The first pass produces a subtle, perhaps sinusoidal spline contour. Next, the splines are reformed to have a smaller pressure angle and sharp corner radii by a second drawing pass through a second die. The cylinder upon which the first spline contour is formed by this process may originate either as a sheet metal disc or as a circular cylindrical cup. The major diameter of the splines formed by the first pass is greater than the major diameter formed by the subsequent pass through the second die, which reforms the original spline contours to the reduced pressure angle configuration.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross section through a diametrical plane of a sheet metal cup formed with splines according to the principles of this invention.
FIG. 2 is a partial cross section taken at axial plane II--II of the sheet metal cup of FIG. 1.
FIG. 3 is a partial cross sectional view showing a partially formed part located between an axial punch and a forming die.
FIG. 4 is a partial cross sectional view taken on a diametrical plane showing the sheet metal cup of FIG. 3 in position between the punch and the forming dies after the punch has been moved into the die to form the splines.
FIG. 5 is a partial cross section taken on an axial plane similar to II--II of FIG. 1 showing the contour of a spline formed on a sheet metal cup after a first stage and a final stage forming process, the first stage producing a more subtle contour at a larger diameter than the final contour.
FIG. 6 is a cross section through a diametrical plane showing a punch, die and a sheet metal cup after the first stage and final stage forming processes, the contours of which are shown in FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIGS. 1 and 2 of the drawing, a finished sheet metal cup 10 includes a hub portion 12 and an axial extending cylindrical portion 14 in which a spline contour has been formed. The splined cup may be a component of an automatic transmission clutch assembly. The pressure angle of the teeth may be about eighteen degrees. The corner radii are much tighter than those commonly formed by drawing. Because of these geometric changes, the pressure between the spline teeth and the mating part is less than would result from torque transfer between the parts if the pressure angle were greater.
FIGS. 3 and 4 illustrate the apparatus for forming the splines on the cup shown in FIGS. 1 and 2. The die assembly comprises a punch 18 connected to the movable member of a hydraulic press and a die 20 suitably secured to the fixed or table portion 22 of the press. A blank holder ring 24 is held by the stem 26 of hydraulic cylinder 28 against the upper surface of a planar sheet metal disk portion 30 of the preformed sheet metal cup 10. An additional blank holder ring 32 holds the sheet against the lower surface of the punch 18 due to the effect of hydraulic pressure applied to the cylinder 34 that moves cylinder stems 36.
The punch 18 is an elongated member having a spline surface formed on its outer contour. The die through which the punch passes has an inner surface conjugate to that of the punch that cooperates with the splined surface of the punch to form splines on the cup 10. The die may have the configuration shown in FIG. 6 that includes an inner cylindrical surface 38, a transition zone 40 and the splined surface 42 that is complementary to the splines of the punch. An alternate die may be made as shown in FIGS. 3 and 4.
Initially the cylindrical surface 14 of the cup is located between the diameter at the base of the punch and the inner diameter of the cylindrical surface 38 of the die. As the press moves the punch through the die, the splines begin to be formed in the transition zone 40 wherein the tooth surfaces appear gradually on the die radially and circumferentially. Finally, when the press has forced the punch and cup through the die, the splines are entirely formed on the cup and the disk portion of the cup has been transformed to the cylindrical longitudinally splined surface 44 shown in FIG. 4.
The diameters of the splined surfaces of the punch and die are established so that an annular space 46 exists bounded by the outer surface of the punch and the inner surface of the splines on the die. Space 46 has a radial dimension that is less than the original thickness of the sheet from which the cup is made. Consequently, when the splines are formed the excess sheet material thickness is moved along the length of the longitudinal portion of the cup in the direction of the axis of the spline. In addition, because the splines are formed on the portion of the cup that was originally a disk and is drawn to a lesser diameter than the outer diameter of the disk, the excess material that would appear at the circumference of the longitudinal splines is forced axially along the axis of the cup in the direction of the splines.
The process for forming the splines may be worked in stages. FIG. 6 shows a sheet metal cup 48 after having been formed with splines whose profile is more subtle than the trapezoidally shaped teeth shown in FIG. 2. For example, a sinusoidally shaped tooth profile may be formed by the process that produces the preformed cup 48. The preferred tooth shape shown in FIG. 2, one having a pressure angle of approximately eighteen degrees with sharp corner radii, may be formed on cup 48 after at least one additional pass of a punch through a second die 52. The second pass begins when the major diameter of the teeth of cup 48 contacts the cylindrical surface 54 of the die 52. The splines on the outer surface of the punch 50 have the preferred shallow pressure angle and are nested within the splines on the preformed cup 48. As the press moves the punch and cup longitudinally into the inner space of die 52, the transition region 56 operates to reform the sinusoidal splines radially and circumferentially. When the punch 50 and cup 48 have passed into the forming region 42 of the die 52 the teeth are formed to the preferred shape of FIG. 2 on the forming surface 58.
Again, an annular space 46 is provided between the outside surface of punch 50 and the inner surface of the forming region 42 of the die. The space 46 has a radial dimension somewhat less than the thickness of the preformed cup 48 so that the final thickness of the cup in the condition shown in FIG. 6 at 60 is closely controlled within a minimum tolerance.
The process for forming the splines on the cup includes at least two passes through forming dies. According to this method, the spline profiles are produced on the cups in two passes that produce the profile shown in FIG. 5. The spline surfaces of the preformed cup 48 are shown in FIG. 5 having a major diameter greater than the major diameter of the final tooth profile shown at 60. It can be seen that the pressure angle of the spline 48 formed on the cup is greater than the pressure angle of the splines 60 and that the corner radii are more generous than those of the final configuration. Preferably, the inside diameter of the cup formed by the first pass and of the splines 60 formed by the second pass are identical, as can be seen in FIG. 5. Furthermore, the thickness of the sheet metal in the region of the crest of the spline can be made different from the thickness of the sheet at the root of the spline. This results because the splined surfaces of the punch 50 and die 52 are established so that the annular space 46 between inner surface of the punch and the outer surface of the die that form the crest of the spline and between the outer surface of the punch and the inner surface of the die that form the root of the spline has a radial dimension that differs between the crest and root areas. Furthermore, the radial dimension of space 46 is less than the sheet thickness of the preformed cup 48. In this way, the final thickness of the sheet can be controlled within a close tolerance to the varying radial dimension of the space.
It is possible that all of the forming operations from which a sheet metal blank is formed to the preferred shapes of FIGS. 2 and 5 may be made on one press during one stroke of the punch through several dies. This process would first draw the sheet metal blank into the form of a cup without splines similar to that shown in FIG. 1 with the use of perhaps five dies. The spline drawing operation would require perhaps two later passes through forming dies similar to dies 52 or 18, and would produce the preferred spline contours in stages by the process described with respect to FIGS. 5 and 6. | A sheet metal blank is placed at the entrance of a die having a splined interior contour. A punch having a conjugate splined surface enters and passes longitudinally through the die. The splines are formed by passing the blank and punch through the die within an annular space whose contour defines the final spline configuration. Alternatively, preformed splines having a large pressure angle and full corner radii are reformed by multiple passes through dies whose configurations vary to produce shallow pressure angle splines and tight corner radii. | 1 |
BACKGROUND OF THE INVENTION (new)
There presently exists in the field of locomotive repair and maintenance the need to safely and quickly remove oil coolers from diesel locomotives, such coolers being of large size, relatively heavy, and well above the floor of the locomotive. Due to the fact that such a cooler is positioned in an oil cooler "pocket" within the locomotive at an acute angle, with access to it being from the side of the locomotive, the cooler must maintain position at near such an acute angle when being removed from the locomotive. Because of this, and because the cooler is well above the floor level, the most commonly used means of removing the cooler is with a "home-made" pulling device that is suspended by a crane or other such means and secured to the side of the cooler, in a laterally extending manner, through a centered hole in the top of the cooler, with the said pulling device having a counterweight on its outer extremity that balances the load. Because the center of balance of the said pulling device differs between the loaded and unloaded status, it must of necessity have two suspension points, and before the cooler can be removed from the locomotive, the pulling device must be secured to the side of the cooler, after which the suspension joints are changed; then, while one man works with "jimmy bars" or other such leveraging tools in an effort to approximately maintain the acute angle of the cooler, the pulling device and the cooler are suspended as one and the cooler is removed laterally out of the oil cooler pocket of the locomotive. Due to the fact that the pulling device is secured to the cooler through the centered hole in top of the cooler, the cooler tends to gravitate toward a vertical position when the pulling device with its load is suspended. Thus it is apparent to someone skilled in the art that considerable physical strain is endured by the person attempting to force the said acute angle of the cooler that is needed to work the cooler laterally out of its pocket. Also, it is apparent that the spatial requirements of the laterally extending pulling device attached to the side of the cooler are such that a wall or other such obstruction located too close to the locomotive being repaired often prevents workers from removing the cooler from the locomotive. Other than make-do contrivances such as that described above, there is no dependable and safe invention for removing an oil cooler from a locomotive without removing the locomotive's hatch.
SUMMARY OF THE INVENTION
The locomotive oil cooler puller has one suspension point central to the load, with said load being attached to the locomotive oil cooler puller in swivel fashion by means of a set of angle adapter plates, which shift the oil cooler from what would be a normally vertical position when suspended to an acute angle when suspended. The said acute angle of the suspended oil cooler allows workers to remove said cooler from a locomotive with a minimum of effort and the solitary suspension point of the said puller allows the workers to remove the oil cooler without changing suspension points. Also, the position of the counterweight of the said puller, being above the oil cooler as opposed to the side of the oil cooler, allows for greater range of lateral movement of the oil cooler as it is being removed from the locomotive.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of an oil cooler in an upright and vertical position, seen from its left side and along a vertical axis relative to its width.
FIG. 2 is a frontal view of an oil cooler as seen taken on line 2 in FIG. 1, showing the horizontal axis relative to the length of the oil cooler with parts pertinent to the invention.
FIG. 3 is a left side view of an oil cooler as it sits in its pocket in a locomotive before the oil cooler puller is attached, showing the pocket angle and parts pertinent to the invention.
FIG. 4 is a left side view of an oil cooler as it sits in its pocket in a locomotive and showing the left angle adapter portion of the invention attached.
FIG. 5 is a left side view of the invention showing the puller applied and the angle adapters secured and hoisting an oil cooler in its pocket in the locomotive.
FIG. 6 is a frontal view of an oil cooler puller as seen from line 6 of FIG. 5 and attached to an oil cooler via the adapter plates and with the oil cooler hoisted in its pocket in a locomotive.
FIG. 7 is a frontal view of the puller detached from the oil cooler and angle adapters portion of the invention, and sharing a common vertical centerline, as they would when connected; showing dimensions vital to the invention.
FIG. 8 is a side view of an angle adapter, showing dimensions vital to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 6 of the drawings, an oil cooler puller 20 for a diesel locomotive 50 consists of a frame 21 that is suspended by means of a clevis 27 attached to a hoist plate 26 that is strategically centered over the oil cooler 1 on a vertical axis 3 of the oil cooler 1 relative to its length (and relative to the width of the locomotive). On the inner end of the upper arm 22 is affixed a counterweight 25 in such a manner that it will not foul against the locomotive 50, said counterweight 25 being the device that balances the oil cooler puller 20 on vertical axis 3 and horizontal axis 4. The lower arm 24 and outer arm 23 of the puller frame 21 has flanges 33 and 34 that are drilled at 30 and 31 to accommodate a probe 32, and all three corners of the frame 21 should have reinforcements 28, as these are critical stress areas. The above-mentioned probe 32 is a replaceable but otherwise a permanent attachment that is secured to the frame 21 by means of applying the probe 32 through the frame probe holes 30 and 31 until the probe flange 29 contacts the inner puller flange 33, at which point the outer probe nut 38 is tightened against the outer frame flange 34 on the outer threaded end 36 of the probe 32. Said probe 32 can thus be removed when it becomes necessary to renovate or replace it. Being, as stated above, a normally permanent attachment to the puller 20, the probe 32 is guided through a pair of angle adapters 39 and 40 that are secured to the oil cooler 1 in lieu of the water intake flanges 7 (as seen in FIGS. 1-3), and which provide a swivel point for the puller probe 32, with the left adapter 39 being mated flush with the probe flange 29, and the right adapter 40 being mated flush against the inner probe nut 37. When suspended, the invention will provide a balanced horizontal axis 4 of the oil cooler 1 relative to its length, which is necessary in removing the oil cooler 1 laterally from its pocket 11 in the locomotive 50. Referring more specifically to FIG. 5 of the drawings, said puller 20 is also designed so that the oil cooler 1 approximates the angle 12 of its pocket 11 in the locomotive 50 when said puller 20 and oil cooler 1 are suspended, such angle 12 being approximately 45 degrees from the vertical position along line 2 of the oil cooler 1 (as seen in FIG. 1). This is accomplished by transferring the customary hoist point at the water intake ears 5 approximately 11 inches toward the front 67 of the oil cooler 1 by means of the adapter plates 39 and 40, said adapter plates 39 and 40 having probe holes 41 (FIG. 4) at their forward ends that accommodate the probe 32 and that are of slightly larger dimension than said probe 32, thus creating a hoist point for the probe 32 that allows a swivel action, with the rear portions of the adapter plates 39 and 40 having a large hole 46 that is designed to accommodate the water intake ears 5 of the oil cooler 1 as seen in FIGS. 4 and 5 of the drawings, with the studs 10 passing through appropriately measured holes 43 (FIG. 8) in the angle adapters 39 and 40 and being secured to said angle adapters 39 and 40 by means of the water intake flange nuts 8, as seen in FIGS. 4 and 5.
Referring to FIG. 7 and thus the dimensions of the invention, it is essential that the measurements listed below are adhered to in order to assure the balances of the oil cooler 1 and the oil cooler puller 20 and thus the success of the invention. A general view of an oil cooler 1 with parts appurtenant to the invention are seen in FIGS. 1 and 2. FIG. 7 shows the oil cooler 1 separate from the puller 20, but with the vertical centerline and center of gravity 3 of the oil cooler 1 being in the same plane as the centerline 3 of the hoist plate 26, as indeed it would be when attached properly to the oil cooler puller 20 shown. This vertical centerline 3 of the oil cooler 1 is based on dimension 69, which is 387/8 inches from plane 57 to plane 68, said dimension 69 allowing for the adapter plates 39 and 40 after their attachment to the oil cooler 1, said adapter plates 39 and 40 being 3/8 inch each and shown as dimension 82 in FIG. 7 as taken from planes 68 and 81. Halving the total of dimension 69, the centerline 3 of the oil cooler 1 is established as being 19 7/16 inches from plane 57 to plane 3, being shown as dimension 59 on the puller 20 and dimension 70 on the oil cooler 1. The probe 32 must be of such construction that its outer end 36, the end that is inserted into the lower arm 24 of the puller 20, will have ample thread protruding beyond the outer frame flange 34 to firmly secure the outer probe nut 38 to the probe 32, and dimension 61 should be 387/8 inches or thereabouts, said dimension being taken from plane 57, which represents the inner surface of the probe flange 29 to plane 60, which represents the beginning of the threaded surface 35 of the inner end of the probe 32. The probe 32 should extend from plane 60 enough to insure that the inner probe nut 37 can be safely snugged up against the right angle adapter 40 when the probe 32 is positioned through the angle adapters 39 and 40 in preparation to hoist the oil cooler 1. The probe 32 also should be of such dimension that it can be positioned into the probe holes 41 of the angle adapters 39 and 40 in a non-binding fashion, and should be constructed of such material and design that maximizes both strength and light weight for suspending a locomotive oil cooler 1 (some versions of these are as much as 800 lbs.), and the diameter of the probe flange 29 should be of such dimension that it is wider than the angle adapter probe holes 41 and the inner arm probe hole 30, and should be firmly affixed to the probe 32. The frame 21 of the puller 20 is to be of a strong and lightweight metal and of such design as to maximize its strength, with reinforcements 28 at its corners as per FIG. 7 and with dimension 55 being 27 inches and extending from plane 57 to plane 52, with plane 52 representing the inner surface of the outer arm 23 of the puller 20, said plane 52 having ample clearance between it and the outer edge of the locomotive hatch 49 (FIG. 6) when hooking the puller 20 to an oil cooler 1. Dimension 56 of FIG. 7 is 55 inches, taken from planes 53 and 54, with plane 53 representing the top of the probe 32 and plane 54 representing the bottom of the upper arm 22 of the puller 20, said dimension 56 also being necessary to assure clearance of the puller frame 21 from the locomotive 50 (FIG. 6) when connecting it to the cooler 1. The counterweight 25 should be constructed in such manner that all of its portions are attached to the upper arm 22 above plane 54 to insure locomotive 50 clearance (FIG. 6), and said counterweight 25 should be of such weight as to perfectly balance the puller 20 when the probe 32 is inserted into the lower arm 24 of the puller 20 and secured with the outer probe nut 38 and with the inner probe nut 37 threaded onto the inner probe threads 35 to a point abutting plane 60 of FIG. 7 and with the puller 20 suspended at 15 in solitary from its clevis 27.
Referring to FIG. 8 of the drawings, the angle adapter 39 or 40 is based on a water intake ear hole 46 that is 53/8 inches in diameter and is centered on vertical axis 63 and horizontal axis 64, which axes 63 and 64 in combination create center axis 62. Because there are two basic types of oil coolers 1 in use in most locomotives 50, it is necessary for convenience to design one basic angle adapter 39 and 40 that will fit both types of oil coolers 1, with the one angle adapter 39 and 40 design providing for the two differing water intake 5 flange stud patterns 72 and 73, one such pattern being the more common 5 5/16 inch stud pattern 73 and the other being a less common 4 15/16 inch stud pattern 72, with both types 72 and 73 using four studs 10 as seen in FIG. 1-5, centered around center axis 62 of the water intake ear 5; therefore, the angle adapter 39 or 40 will have eight stud holes 43, 13/32 inches in diameter, drilled in accordance to stud hole patterns 72 and 73, centered around axis 62, as seen in FIG. 8. The angle adapters 39 and 40 are equipped with two suspension points 41 and 42, said suspension points 41 and 42 being the probe hole 41 for use with the puller 20 and the vertical hoist hole 42 which can be utilized for suspending the oil cooler 1 in a vertical position without use of the puller 20. The bottom of the probe hole 41 should be positioned on plane 66 which is taken from the center of stud hole 44 across the center of stud hole 45, and the centerline 75 of the probe hole 41 should be 7 inches from plane 74, being seen as dimension 76 in FIG. 8 of the drawings. The bottom of the vertical hoist hole 42 should be on the same plane as the top 65 of the oil cooler 1 and the top of the vertical hoist hole 42 should be on horizontal plane 79 with dimension 80 being 21/2 inches. Dimension 78, taken between planes 65 and 77, should be 2 inches. The angle adapters 39 and 40 are of identical dimensions, the only difference between them being their markings 47 and 48, which prevents the workers from hooking them to the oil cooler 1 in an incorrect manner. These markings 47 and 48 are determined by positioning the angle adapter 39 or 40 over the oil cooler's 1 water intake flange studs 10 with the angle adapter 39 and 40 probe holes 41 pointing toward the front 67 of the oil cooler 1 and the angle adapter 39 and 40 vertical hoist hole 42 pointing toward the top 65 of the oil cooler 1 and stamped accordingly as the viewer would stand facing the respective right or left side of the oil cooler 1. | This invention is a device for removing an oil cooler from a diesel locomotive, having one suspension point, and having a laterally extending upper arm, a vertical arm, and a laterally extending lower arm that cradles and supports a laterally extending probe, which is attached in pivotal fashion to a pair of lifting plates that are removably affixed to the oil cooler. The upper arm has a lifting clevice attached to a point central to the load, and a counterweight that balances the device from that central point. When the device is lifted by crane or other methods from the lifting clevis, the oil cooler is balanced laterally while at the same time maintaining an acute angle similar to the angle that the oil cooler maintains when secured in the locomotive. | 5 |
CROSS-REFERENCES TO RELATED APPLICATIONS
This application is the U.S. national phase of International PCT Application No. PCT/US2005/010833, filed Mar. 30, 2005, which designated the United States. PCT/US2005/010833 claims the benefit of U.S. Provisional Patent Application Ser. No. 60/557,418, filed Mar. 30, 2004. The entire contents of these applications are herein incorporated by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
(NOT APPLICABLE)
BACKGROUND OF THE INVENTION
The present invention relates to an attachment for a telescopic material handler and, more particularly, to such an attachment for manipulating a load with five degrees of freedom.
Modern construction technologies utilize several types of materials delivered in the form of long panels. The panels have great advantages from aesthetic (less visible joints, high quality of finish), safety (high fire resistance) and economical (minimal number of construction steps, good insulation, air tight) points of view. Installation, however, requires special equipment and processes to install them in a safe, efficient way with minimal losses due to damage.
There are known at least two products for telescoping material handlers and vertical mast forklifts. In one version, the attachments are designed for work with different carriers—supported by forks of a forklifts and designed to connect to a boom of a telescoping material handler. Usually, telescoping handler attachments have an operator platform. The attachments are fully self-contained. A vacuum pump, a hydraulic system for lift functions and a control system are powered by batteries built into the attachment base. The attachments slip over forks of the telehandler making them easy to apply on different types of machines. Another attachment is designed to hang from a crane.
Another version uses a quick attachment change connection usually used with rotating models of telehandlers. Rotating machines have the boom mounted on its rotating upper structure (turntable), very similar to mobile cranes and excavators. Additional mechanisms effect fine adjustment and positioning of the panel.
BRIEF SUMMARY OF THE INVENTION
The present device is a telescopic telehandler (e.g., forklift) attachment that is to be used to pick, manipulate, transport and aid in the installation of both vertical and horizontal building panels (cladding) and other construction materials such as pipes and the like. These tasks will be achieved through wireless control over five degrees of freedom and the interaction of an additional operator in an aerial work platform (AWP).
The device is able to handle variety of cladding panels and other construction materials. Exemplary panels have dimensions up to 1.3×8.0 meters in size and a mass of 350 kg or more. Panels are preferably handled by means of an onboard vacuum system and are manipulated and controlled over five degrees of freedom by the construction of the attachment.
In an exemplary embodiment of the invention, an attachment for a telescopic material handler enables support and manipulation of a load. The attachment includes a gripping system that securely holds the load, and a manipulation assembly supporting the gripping system. The manipulation assembly is movable in at least five degrees of freedom. An operator-controlled wireless control system effects control of the manipulation assembly. Preferably, the load is either building panels or pipes.
In one arrangement, the manipulation assembly is preferably pivotable about a first axis generally perpendicular to a ground plane, defining a first degree of freedom; the manipulation assembly includes a main arm supporting the gripping system, wherein the main arm is pivotable about a second axis generally parallel to the ground plane, defining a second degree of freedom; the manipulation assembly also includes a panel rotator assembly attached to the main arm via a four bar mechanism, wherein the four bar mechanism pivots the panel rotator assembly about a third axis generally parallel to the ground plane and the second axis, defining a third degree of freedom and effecting rotation of the load; wherein the panel rotator assembly rotates the gripping system relative to the main arm about a fourth axis generally parallel to the ground plane and perpendicular to the second and third axes, defining a fourth degree of freedom and effecting rotation of the load about a normal axis; and wherein the gripping system is translatable relative to the main arm, defining a fifth degree of freedom.
The gripping system may include a vacuum pump, a plurality of vacuum cups, and a vacuum reservoir. In this context, the vacuum cups may be divided into at least two independent circuits, where each independent circuit includes a vacuum reservoir. Each independent circuit of the gripping system may further include a manifold valve that separates its respective vacuum reservoir from the vacuum pump, wherein upon failure of the vacuum pump, each of the manifold valves closes to preserve vacuum in its respective reservoir. The gripping system may further include a vacuum switch that measures a vacuum level, where the attachment further includes a first signal coupled with the vacuum switch, the first signal indicating that sufficient vacuum has been achieved. The attachment may also include a system controller receiving input from the vacuum switch and opening and closing the manifold valves based on the vacuum level. Preferably, the system controller controls the vacuum pump and the first signal, where the attachment further includes at least a second signal activated by the system controller when the vacuum level is below a predetermined level. In one arrangement, the gripping system additionally includes a clamp. Still further, the vacuum cups may be provided with a soft touch attachment including isolation and suspension components that protect the load.
The operator-controlled control system may include a primary radio transmitter and a secondary radio transmitter, where control of the load i& transferable between the primary and secondary radio transmitters. The attachment preferably also includes a visual indication of which radio transmitter is in control of the load.
In another exemplary embodiment of the invention, a method of manipulating a load includes the steps of holding the load with a gripping system; and supporting the gripping system with a manipulation assembly for movement in at least five degrees of freedom via an operator-controlled control system. If the load is a cladding panel, the method may further include flipping the cladding panel over prior to installation. The flipping step may include the steps of attaching the gripping system to a first side of the cladding panel, rotating the cladding panel about an axis generally parallel to a longitudinal axis of the cladding panel, releasing the cladding panel onto a support member, and attaching the gripping system to a second side of the cladding panel.
In yet another exemplary embodiment of the invention, an attachment for a telescopic material handler enabling support and manipulation of a load includes a gripping system that securely holds the load, the gripping system including a vacuum pump, a plurality of vacuum cups, and a vacuum reservoir, wherein the vacuum cups are divided into at least two independent circuits, and wherein each independent circuit includes a vacuum reservoir; a manipulation assembly supporting the gripping system, the manipulation assembly being movable in at least five degrees of freedom; an operator-controlled control system effecting control of the manipulation assembly; and a plurality of indicators signaling a status of the attachment.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other aspects and advantages of the present invention will be described in detail with reference to the accompanying drawings, in which:
FIG. 1 illustrates the wireless controllers to effect manipulation of the load;
FIG. 2 is a plan view of the attachment showing panel swing;
FIG. 3 is a side view of the attachment showing panel lift;
FIG. 4 is a side view of the attachment showing panel tilt;
FIG. 5 is an end view of the attachment showing rotation of a panel;
FIG. 6 is a side view of the attachment showing panel shift;
FIG. 7 is a schematic illustration of the electrical and control system;
FIG. 8 is a schematic illustration of the vacuum system;
FIGS. 9 and 10 illustrate an alternative arrangement of the gripping system including a clamp;
FIGS. 11-14 illustrate a process for flipping a panel; and
FIG. 15 illustrates a soft touch attachment for the suction cup array.
DETAILED DESCRIPTION OF THE INVENTION
Manipulation of the load is accomplished with five powered degrees of freedom (DOF), and the hydraulic power for these motions may be obtained from the telehandler auxiliary circuit. The structure and its motions are described below from the telehandler attachment out to the vacuum cups. All of the device's degrees of freedom are controlled via a wireless system (described below). The controls can be sees in FIG. 1 .
FIG. 2 is a plan view of the telehandler attachment 10 of the present invention. The attachment 10 includes a coupling section 12 coupleable with the telehandler via any suitable means. FIG. 3 is a side view of the attachment 10 showing the coupling section 12 fixed to a portion of the telehandler T.
The attachment 10 includes a gripping system 13 for securely holding the load and a manipulation assembly 14 supporting the gripping system 13 . As described in more detail below, the manipulation assembly 14 is movable in at least five degrees of freedom.
In this context, the manipulation assembly 14 is secured to the coupling section 12 via a first pivot 18 having an axis generally perpendicular to a ground plane (i.e., the plane of the page in FIG. 2 ), defining a first DOF. The first DOF allows for plus/minus rotation (for example +/−90°) of the entire manipulation assembly 14 with respect to the telehandler boom. This rotation can be seen via arrows in FIG. 2 and is used to position the manipulation assembly 14 normal (in the horizontal/ground plane) to the cladding surface.
With reference to FIG. 3 , the manipulation assembly 14 includes a base arm 15 secured to the coupling section 12 and a main arm 16 pivotally attached to the base arm 15 via a second pivot 20 . The main arm 16 supports the gripping system 13 as shown. Pivoting of the main arm 16 about the second pivot 20 defines a second DOF. The pivot 20 is oriented with its axis generally parallel to the ground plane. The second DOF rotates the main arm 16 of the device from horizontal to vertical, as shown via arrows in FIG. 3 . In a preferred embodiment, this motion in effect allows for 900 mm of horizontal and vertical (albeit interdependent due to the traversed are) adjustment of the panel.
With reference to FIG. 4 , the manipulation assembly 14 additionally includes a four-bar mechanism 21 that moves a panel rotator assembly 23 installed between the main arm 16 and the gripping system 13 . The panel rotator assembly 23 is attached through the four bar mechanism 21 to the main arm 16 via a third pivot 22 oriented with its axis generally parallel to the ground plane and the axis of the second pivot 20 . Pivoting about the third pivot 22 defines a third DOF. The third DOF is achieved by powering the panel rotator assembly 23 through the four-bar mechanism 21 and allows for rotation of the panel, for example 180° rotation, as seen via arrows in FIG. 4 , in order to un-nest the packaged panels and/or flip the panels delivered packaged in the wrong orientation.
FIG. 5 is an end view of the attachment showing the gripping system 13 rotatable relative to the main arm 16 by means of the panel rotator assembly 23 about a fourth pivot 24 whose axis is oriented generally parallel to the ground plane and perpendicular to the axes of the second and third pivots 20 , 22 , defining a fourth DOF. As shown by the arrows in FIG. 5 , the fourth DOF effects rotation (for example plus/minus 100 degrees) about the panel normal axis from a transport position of horizontal to provide for either horizontal or vertical cladding operations. FIG. 5 shows the gripping system 13 supporting a cladding panel P as a load. The load is exemplary as other construction materials such as pipes or the like may also be supported by the gripping system 13 .
With reference to FIG. 6 , the gripping system 13 is also translatable relative to the main arm 16 as shown via the arrows in FIG. 6 . This translation defines a fifth DOF, which provides panel translation (for example plus/minus 150 mm) in a direction normal to the panel edge. This motion seats the ‘tongue and groove’ seal that is incorporated on the cladding panels P.
The structure of the device also includes a compartment 25 with a lockable, hinged hood that houses the majority of the electronic, pneumatic and hydraulic components. The device also provides for some flexibility in its transport package size. The wings 27 ( FIG. 2 ) that support the outer two vacuum reservoirs can be folded back to reduce the package width.
With reference to FIGS. 2 , 7 and 8 , the gripping system 13 includes a vacuum pump 26 , vacuum cups 28 divided into independent circuits, each circuit with its own vacuum reservoir 30 , and manifold valves 32 . In an exemplary embodiment, twenty vacuum cups 28 are divided into six independent circuits, four circuits with three vacuum cups 28 and two circuits with four vacuum cups 28 . As shown in FIG. 2 , there are three groups of vacuum cups; four circuits with three vacuum cups in a central cluster 28 a and two circuits 28 b with four vacuum cups to the right and left of the central cluster 28 a . Each group of vacuum cups is connected to a vacuum reservoir 30 , storing vacuum in the event of a vacuum system failure. A normally closed manifold valve 32 separates each vacuum reservoir 30 from the rest of the vacuum system. The vacuum pump 26 , mounted in the compartment, creates the vacuum in the system.
The vacuum level in the system is measured using a vacuum switch 34 . A signal such as a green light will illuminate on the device when sufficient vacuum is achieved. Upon sufficient vacuum, the cladding panel P can be manipulated into the appropriate mounting position and fastened to the building. Once the cladding panel P is attached to the building, the vacuum pressure is released from all circuits. The vacuum release is initiated by an operator through a switch selection on the wireless control system.
In the event of a failure in the vacuum system (as indicated by the vacuum switch 34 ), an alarm will sound, and the sufficient vacuum indicator will go off. The manifold valves 32 on each of the vacuum reservoirs 30 will close, preserving vacuum in each reservoir 30 . This remaining vacuum will hold the panel P for a period of time, so the operator can lower the panel into a safe position. A failure in the electrical system or vacuum pump will also cause these valves 32 to close, holding the panel. Upon restart of the vacuum system, the vacuum switch 34 will check for vacuum and assume there is a panel if sufficient vacuum is established by means of the vacuum switch 34 , in which case the manifold valves 32 will reopen, and the sufficient vacuum indicator will go on.
The electrical and control system allows wireless radio remote control of the device, handles failures, stops the operator from moving into an unsafe orientation of the device, and increases the safety of the product. The user will control the device with two preferably differently-colored battery powered radio transmitters (e.g., blue and yellow). The blue transmitter, for example, will be the primary, and the yellow transmitter will be the secondary. One or zero transmitters have control of the device at any time. A pitch/catch system is used to transfer control between transmitters. As shown in FIG. 1 , each transmitter includes seven toggle switches, a proportional trigger, and an emergency stop (e-stop). The toggle switches control the vacuum pump, transferring control, releasing the panel, and toggling between the five degrees of freedom. The proportional trigger activates the selected function. The e-stop turns the transmitter off. When the e-stop is pressed, the device shuts down the movement functions, although the vacuum pump status does not change.
The electrical and control system preferably includes two proximity sensors 50 a , 50 b —one for each panel lift and tilt, two vacuum switches 51 , and one radio receiver 52 with a logic controller (PLC). The system controls the hydraulic block 53 , the vacuum pump 26 , the audible alarm 55 , the manifold valves 32 , the panel release valve 57 , and three indicators 58 . The indicators are preferably differently-colored lights, such as blue, yellow and green. The radio receiver controls the hydraulic block 53 , with the exception of the two proximity sensor cutouts, which are controlled via relay logic. The radio receiver also controls the vacuum pump power relay, the panel release valve, and the blue and yellow control lights. The receiver along with relay logic, controls the audible alarm 55 , which is enabled when the vacuum pressure holding a panel is unexpectedly lost. Whenever the audible alarm 55 is enabled, the manifold valves 32 are disabled by relay control, causing them to close. The tilt up motion is limited by relay logic to prevent the panel from being tilted beyond 15 degrees from the vertical reference frame of the main lift arm 16 when the lift arm 16 is raised above horizontal. The lift up motion is disabled by relay logic when the panel is tilted back over 15 degrees from the vertical reference frame of the lift arm 16 . These cut outs are triggered by the proximity sensors 50 a , 50 b . The pump side vacuum switch 51 controls the green light, which is enabled when the system has reached the appropriate vacuum level.
The electrical power to the system is generated by either a hydraulic or engine-powered generator 60 . Preferably, power is generated by the generator 60 at 120 VAC and is converted to 12 VDC with a step down transformer 61 and a rectifier. On the 12 VDC circuit, in the preferred arrangement, there are three lights 58 , six manifold valves 32 , the audible alarm 55 , four relays, ten hydraulic valves 53 including a proportional valve, two proximity switches 50 a , 50 b , two vacuum switches 51 , and the radio controller 52 . On the 120 VAC circuit, there are the vacuum pump 26 and the transformer 61 .
The electrical and control system increases the safety of the device with proximity sensor 50 a , 50 b cutouts, as described above, with the audible alarm 55 and closing the manifold valves 32 on a loss of vacuum, and with the indicator lights 58 to signal the status of the device. When the vacuum holding a panel is unexpectedly lost, the manifold valves 32 close and use a small reservoir of vacuum to hold the panel in place for some time. This allows the panel to be safely lowered to the ground before the vacuum falls unsafely. The blue light flashes when the blue transmitter is in control of the device, and the yellow light flashes when the yellow light is in control. Both lights will flash when neither is in control. The green light flashes when there is enough vacuum to safely maneuver the panel. The lights quickly show the operators who is in control of the system and if the panel is safe to move.
FIGS. 9 and 10 illustrate an alternative arrangement of the gripping system 13 with additional gripping structure. In this arrangement, two pairs of clamps 80 are provided on the center array of vacuum cups. The clamps 80 are preferably hydraulically actuated via a cylinder 82 and pivot 84 and secure the panel P during transport.
An exemplary application of the invention including installation of cladding panels P will be described with reference to FIGS. 11-14 . The invention advantageously provides construction crews with a method of installing cladding panels and other construction materials using two machines: (1) a telehandler with two attachments including (i) a fork and (ii) the telehandler attachment 10 of the invention, and (2) an aerial work platform (AWP).
In installing cladding panels on a building, a material handler with forks initially unloads the delivery truck and stacks panel bundles in a staging area. The material handler with forks moves the panel bundles from the staging area to an area in close proximity to the building. The fork attachment is then changed to the telehandler attachment 10 of the invention.
Since all panels for installation have to be picked up on the finished outside surface for installation, no matter how they are delivered, the machine performs panel sorting and flipping as necessary. With reference to FIGS. 11-14 , the panel bundle PB rests on a storage shelf 102 of a saw horse accessory 100 . The storage shelf 102 serves to prevent the panels from possible damage if they would rest on uneven ground. The accessory also includes a higher surface 104 on which the panel rests during a flipping process. The panel needing to be flipped is picked up by the gripping system 13 of the attachment 10 ( FIG. 11 ), then flipped over by pivoting the four bar mechanism 21 ( FIG. 12 ). The flipped panel is then lowered into engagement with the higher surface 104 of the saw horse accessory 100 and released ( FIG. 13 ). The attachment 10 is then positioned with the gripping system 13 adjacent the opposite side of the panel, and the panel is captured for installation ( FIG. 14 ). The panels are flipped one by one as needed and immediately delivered to the building and installed either in a vertical or a horizontal orientation.
The ability of the device to mechanize sorting and flipping of the panels is of importance for avoiding panel damage and eliminates hand labor after the panel is delivered to the building and positioned in close proximity to its final position.
Cooperation between the operator of telehandler and a worker on the AWP for installing the panel on a building will be described. The worker on the AWP has a better ability to check for proper alignment between the panel being installed and previously-installed panels and to supervise making a joint. The primary and secondary radio control units and signaling method allows the worker on the AWP to take control of some positioning functions of the telehandler attachment 10 to precisely position the panel, prevent damage, and facilitate installation.
After the panel is located in place, and at least some fasteners are placed to keep the newly installed panel temporarily fastened to the building, the attachment 10 releases the panel, and the telehandler is moved to start a new cycle. In the meantime, the worker on the AWP completes installation including installing all fasteners, removing protective film from surface of the panel, and preparing the joint for the next panel.
Another exemplary application utilizes the attachment 10 of the invention along with a cladding installation system coupled with a scissors lift or the like, such as the system described in U.S. patent application Ser. No. 10/834,103, the contents of which are hereby incorporated by reference. In this application, the attachment 10 is utilized to sort and flip the panels as necessary, then deliver the panels to the installation system.
With reference to FIG. 15 , the system may be provided with a soft touch attachment for the suction cup array. This could include, but is not limited to, isolation and suspension components to protect the medium being handled by the device. This component allows for four inches of motion for the panel to reduce the likelihood of material damage during the installation process. The soft touch variation allows the device to be used in the glass and stone fascia installation markets.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. | An attachment for a telescopic material handler supplies five degrees of freedom (DOF) for the task of picking, manipulating and aiding in the installation of vertical and horizontal wall cladding and other construction materials. The cladding can be of a size up to 1.3×8.0 m and a mass of 350 kg. The control and positioning of the load is accomplished through standard operation of the telehandler in conjunction with wireless control of the five DOF of the device. Hydraulic power for the device functions may be supplied through the telehandler auxiliary circuit. The auxiliary flow also powers a hydraulic generator, which supplies the device with electrical power for both system logic and control and vacuum generation. The cladding panels are handled by the vacuum system. | 4 |
TECHNICAL FIELD
The present invention relates to Session Initiation Protocol message handling in a communications network.
BACKGROUND
IP Multimedia Subsystem (IMS) is the technology defined by the Third Generation Partnership Project (3GPP) to provide IP Multimedia services over mobile communication networks (3GPP TS 22.228). IMS provides key features to enrich the end-user person-to-person communication experience through the integration and interaction of services. IMS allows new rich person-to-person (client-to-client) as well as person-to-content (client-to-server) communications over an IP-based network.
The IMS makes use of the Session Initiation Protocol (SIP) to set up and control calls or sessions between user terminals (UEs) or between UEs and application servers (ASs). SIP is described in RFC3261. The Session Description Protocol (SDP), carried by SIP signalling, is used to describe and negotiate the media components of the session. Whilst SIP was created as a user-to-user protocol, IMS allows operators and service providers to control user access to services and to charge users accordingly.
Within an IMS network, Call/Session Control Functions (CSCFs) operate as SIP entities within the IMS. The 3GPP architecture defines three types of CSCFs: the Proxy CSCF (P-CSCF) which is the first point of contact within the IMS for a SIP terminal; the Serving CSCF (S-CSCF) which provides services to the user that the user is subscribed to; and the Interrogating CSCF (I-CSCF) whose role is to identify the correct S-CSCF and to forward to that S-CSCF a request received from a SIP terminal via a P-CSCF.
IMS service functionality is implemented using application servers (ASs). For any given UE, one or more ASs may be associated with that terminal. ASs communicate with an S-CSCF via the IMS Service Control (ISC) interface and are linked into a SIP messaging route as required (e.g. as a result of the triggering of IFCs downloaded into the S-CSCF for a given UE).
A user registers in the IMS using the specified SIP REGISTER method. This is a mechanism for attaching to the IMS and announcing to the IMS the address at which a SIP user identity can be reached. In 3GPP, when a SIP terminal performs a registration, the IMS authenticates the user using subscription information stored in a Home Subscriber Server (HSS), and allocates a S-CSCF to that user from the set of available S-CSCFs. Whilst the criteria for allocating S-CSCFs is not specified by 3GPP, these may include load sharing and service requirements. It is noted that the allocation of an S-CSCF is key to controlling, and charging for, user access to IMS-based services. Operators may provide a mechanism for preventing direct user-to-user SIP sessions that would otherwise bypass the S-CSCF.
Further signalling sent to and from the user is also controlled using SIP signalling. Each SIP client between the two end-points of the signalling uses the Domain Name System (DNS) to route the signalling and find the next hop to route the request. SIP uses several mechanisms for routing requests between hops. One of the key mechanisms used is rewriting the Request-URI in he header of the SIP message to the next hop to which the request will be routed. This will cause the original target identity in the header to be replaced with an address of an intermediate hop. The original target address is lost, and this can cause problems in scenarios where the receiver requires knowledge about the target address that was used to address that receiver.
For example, in the case where a single User Agent (UA) has multiple addresses associated with it, a single address is registered and the UA would accept incoming signalling sent to any of the associated addresses. It is desirable for the UE to know which of the addresses is being used when it receives, for example, a call, as it may play different ring tones depending on which address was used by the originator of the call. However, if the Request-URI is re-written then UA will not know which address was used to make the call.
Another example where the problem arises is in making a call for emergency services using Voice over IP (VoIP). A SIP INVITE request for an emergency must be marked to indicate that it is an emergency call in order that it can receive priority treatment. The marking is made to the target address of the request itself, to identify the target as being a recipient of emergency service calls. The Request-URI contains an SOS URN, which must remain in the Request-URO as the request is routed towards the emergency services target. However, this is lost if any of the intermediate nodes re-write the Request-URI.
More examples of scenarios where re-writing the request causes a problem can be found in internet draft IETF draft-rosenberg-sip-ua-loose-route-01. The cases where Request-URI rewrites occur are as follows:
Retarget: In this case, the Request URI contains a new target address, and so the end target is no longer the original end target; Reroute: In this case, the target address remains the same but a different or intermediary route is chosen to reach the same user, and so the Request-URI is rewritten to contain the routing address Translation: In this case a name (URN) is translated to an address.
The problem described above has been partly addressed by using the Route header, together with loose routing (http://tools.ietf.org/html/rfc3261). According to loose routing, the Request-URI is not overwritten, and so it will always contains the URI of the target UA. The SIP request is sent to the URI in the topmost Route header field, and so the Request-URI does not always contain the URI of the next hop to which the request will be sent. Effectively, the request target and the next route destination are kept separate in the SIP request header.
Another part of the problem has been solved on the last hop from a home proxy to the UA, in which a P-Called-Party-ID header retains the Request-URI value which had been replaced by the contact address of the registered user (see http://tools.ietf.org/html/rfc3455).
The internet draft (http://tools.ietf.org/html/draft-rosenberg-sip-ua-loose-route-01) proposes to extend the routing mechanism by extending the loose routing concept to the UE. However, there are several problems with this that need to be addressed. A simple extension of loose routing to UEs would not work unless the target node for the next physical hop supports loose routing. Each entity in the path must therefore know that the next-hop entity supports loose routing. If previous entities in the signalling path have used the loose routing mechanism, and an entity realizes that the next hop does not support it, it must “fix” the message by restoring the correct value back into the R-URI in order for that next hop to be able to process and route the message correctly.
Furthermore there are services that rely on receiving entities having knowledge of the “previous” R-URI that will only work if entities (which have nothing to do with the service as such) in the message path support the mechanism, which makes the usage of such services very limited and unpredictable.
Examples of scenarios in which the application of the loose routing mechanism to UEs would make the SIP routing fail include the following:
1. An intermediate SIP proxy (such as a Call Session Control Function in an IMS network) that does not support the loose routing mechanism. Such a SIP proxy would receive a Route header with one entry representing the proxy, and remove the Route entry. The proxy would then attempt to route the message based on the Request URI, using RFC 3263 procedures, and find the first proxy that the target identity resolves to. This would result in a loop back to the first proxy that the target normally resolves to, and so consequently routing would fail.
2. A Home SIP proxy that does not support the mechanism. In this case the home SIP proxy would receive a Route header with one entry representing the Home SIP proxy and remove the Route entry. The Home proxy would then analyse the Request URI to see if it is a registered Address of Record (AoR). Of course, it will not be and so the Home SIP proxy will attempt to route the message based on the Request URI, using RFC 3263 procedures. It will find the first proxy that the target identity resolves to, resulting in a loop back to the first proxy that the target normally resolves to, and so consequently routing would fail.
3. A Media Gateway Control Function (MGCF) that receives a request that has been routed using the loose routing mechanism may find a Uniform Resource Name (URN) in the Request URI. The MGCF cannot interwork with the URN and so call setup fails.
SUMMARY
The inventors have realised the problems associated with extending the loose routing mechanism, and devised a method and apparatus to address this.
According to a first aspect of the invention, there is provided a method of handling Session Initiation Protocol message in a communications network. A network node receives a Session Initiation Protocol (SIP) message, which comprises Request-URI header. The node rewrites the Request-URI header in the SIP message, and adds information to the SIP message useable by a remote node to determine the current target address of the message. The SIP message is then sent to a further node. In this way, any remote node that receives the message can determine the current target in the SIP message, even if the target has been re-written in the Request-URI as the result of a translation or re-routing operation. The information may include, for example, information identifying the current target identity or information identifying where a Request-URI has been re-written as a result of a re-target operation. The current target address may optionally be the original target address of the message or, in the case where the Request-URI has been re-written owing to a retarget operation, the current target address is the address as re-written by the retarget operation.
Optionally the information useable by the remote node to determine the current target address of the message comprises a new message header, the header including the current target identity. This is referred to herein as a “Target” header. In an alternative embodiment, the information useable by the remote node to determine the current target address of the message comprises a tag associated with the entry in a History-Info header of the message. The tag indicates that the entry arose from a re-target operation. In this case, the node optionally removes existing tags associated with previous target address entered in the History-Info header, and associates a tag with the current target address entered in the History-Info header. This reduces the size of the SIP message.
According to a second aspect of the invention, there is provided an intermediate node for use in a communications network. The intermediate node, which may be a SIP proxy such as an IMS Call Session Control Function, comprises a receiver for receiving a Session Initiation Protocol message. A processor is provided for rewriting a Request-URI header in the SIP message and adding information to SIP message useable by a remote node to determine the current target address of the message. The intermediate node further comprises a transmitter for sending the SIP message to a further node. By providing the information, a remote node can determine the current target address even if the target has been re-written in the Request-URI as the result of a translation or re-routing operation.
The processor is optionally arranged to insert a new message header in the SIP message, the header including the current target identity. Alternatively, the processor is optionally arranged to add a tag to an address entry in a History-Info header of the message, the tag indicating that the entry arose from a re-target operation. In a further alternative, the processor is arranged to add a tag to an address entry in a History-Info header of the message, the tag indicating that the entry contains a target address of the message.
According to a third aspect of the invention, there is provided a node for use in a communications network, the node comprising a receiver for receiving a SIP message, and a processor for determining, on the basis of information added to the message by an intermediate node between an originating node and the node, the current target address of the message. The node can therefore determine the current target address of the SIP message even if the target has been re-written in the Request-URI as the result of a translation or re-routing operation by an intermediate node. The node may be a terminating node such as User Equipment, or may be an intermediate node such as an Application Server.
Optionally, the processor is arranged to determine the current target address of the message by determining the contents of a target header inserted in the message by the intermediate node prior to sending the message to the node. In an alternative option, the processor is arranged to determine the current target address of the message by analysing tagged entries in a History-Info header of the message.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow diagram illustrating the basic steps of an embodiment of the invention;
FIG. 2 is a signalling diagram showing example signalling according to embodiments of the invention;
FIG. 3 illustrates schematically in a block diagram an intermediate node in a SIP signalling path according to an embodiment of the invention; and
FIG. 4 illustrates schematically in a block diagram a terminating node according to an embodiment of the invention.
DETAILED DESCRIPTION
In order to overcome the problems described above, it is proposed that a SIP message retains the original target information in a separate information element from the Request-URI. Ways in which this can be achieved include introducing a new SIP header, and extending the usage of the existing History-Info header.
New Target SIP Header
A new header, referred to herein as a “Target” header, is inserted into a SIP message by a SIP entity whenever the Request-URI is rewritten by the SIP entity (assuming that a Target header is not already present in the SIP message), and the rewriting is due to a rerouting of the request. If the Target header is already present in the SIP message, and the Request-URI is rewritten due to a retarget operation, then the Target header is rewritten with the new target. The Target header includes the initial target identity that was used to generate the message. In a further alternative, the Target header is removed in the case of retargeting.
If the Target header is available on the request and the Request-URI is rewritten due to a re-route or translation operation, the Target header will be left unchanged.
For all alternatives in this embodiment, a receiving entity that receives a SIP message containing a Target header can determine the current target from the Target header field.
Furthermore, for all alternatives in this embodiment a receiving entity that receives a SIP message not containing a Target header can determine the current target from the Request-URI.
If a SIP entity, which acts as registrar/home proxy for the terminating user, re-writes the Request-URI with the contact address of the registered UA it may additionally insert a P-Called-Party-ID header field with the previous value of the Request-URI, as described in RFC3455.
Note that the Target header field and P-Called-Party-ID header fields have different semantics. Where the Target header field represents the initial target identity that was used to initiate a session to the target, the P-Called-Party-ID represents the last AoR used to reach the user before Request-URI value for cases where the last route taken presents significant information.
Extending History-Info Usage
The History-Info header (RFC4244) is a blind record of values that a Request URI has had in the course of the message being routed. Consequently this header also contains the target for the current request.
An alternative to the new Target header solution described above is to extend the use of the History-Info header by marking the entry in the History-Info header recording the current target of the request. When a SIP message traverses a SIP entity supporting this extension and the SIP entity re-writes the Request-URI value due to a retarget operation, the SIP entity adds the previous Request-URI value into an entry of the History-Info header field and additionally it tags that entry as a retarget entry. In order for a receiving entity to determine which History-Info header entry is pointing towards the intended target, it can lookup the last History-Info entry that is tagged as being due to a retarget operation, or when no entry is tagged, to use the first entry. The sequence of tagged entries provides a target trail as a meta level in the history.
In a further alternative, only the current target of the request is marked. When a SIP message traverses a SIP entity supporting this extension and the SIP entity re-writes the Request-URI value due to a retarget operation, the SIP entity adds the previous Request-URI value into an entry of the History-Info header field and additionally it tags that entry as a retarget entry. The SIP entity additionally removes such tags from previous History-Info elements. In order for a receiving entity to determine which History-Info header entry is pointing towards the intended target, it can lookup the last History-Info entry that is tagged as being due to a retarget operation, or when no entry is tagged to take the first entry.
In a further alternative mechanism, only re-targets are recorded in the History-Info header, although that may be incompatible with SIP elements that implement the current RFC4244. In order for a receiving entity to determine the current target, it looks up the last History-Info entry.
For all alternatives in this embodiment, a receiving entity that receives a SIP message not containing a History-Info header can determine the current target from the Request-URI.
If the SIP entity acts as registrar/home proxy for the terminating user, it re-writes the Request-URI with the contact address of the registered UA and it may additionally insert a P-Called-Party-ID header field with the previous value of the Request-URI, as described in RFC3455.
The alternative embodiments described above can be summarized in the flow diagram of FIG. 1 , with the following numbering corresponding to the numbering in the Figure:
1. A SIP message is received at a SIP proxy node, for example a CSCF in an IMS network; 2. The node re-writes the Request-URI header of the SIP message; 3. The node checks to see if the Request-URI rewrite is due to a retarget operation. If so, then move to step 4 , if the retarget is due to a reroute or translation operation, then move to step 6 ; 4. Where the target header embodiment is used, check to see if a target header is already present in the SIP message. If so, then move to step 5 , if not then move to step 8 . Where the History-Info header embodiment is used, the node checks to see if the current recorded target is tagged in the History-Info header. If so, then move to step 5 , if not then move to step 8 ; 5. Where the target header embodiment is used, the target header is either removed or rewritten with the new target, then move to step 8 . Where the History-Info header embodiment is used, the history entry that represents the new current target is tagged. Additionally a tag may be removed from a previously tagged entry. Then move to step 8 ; 6. Where the target header embodiment is used, check to see if a target header is already present in the SIP message. If so, then move to step 8 , if not then move to step 7 . Where the History-Info header embodiment is used, the node checks to see if the current recorded target is tagged in the History-Info header. If so, then move to step 8 , if not then move to step 7 ; 7. Where the target header embodiment is used, a target header is inserted into the SIP message with the Request URI value before the retarget operation. Where the History-Info header embodiment is used, no further action is required. 8. The SIP message is sent to a further node in the communications network.
Referring to FIG. 2 , an example signalling diagram is shown. Where the target header embodiment is used, message 1 from UEA to rerouting intermediary 1 is a SIP INVITE message including target1 in the Request URI. The following correspond to the route and target for each message in the signalling sequence:
m1
INVITE
target1
m2
INVITE route1
Target: target1
m3
INVITE route2
Target: target 1
m4
INVITE target2
m5
INVITE route3
Target: target2
In another target header embodiment, the signalling sequence shown in FIG. 2 is as follows:
m1
INVITE
target1
m2
INVITE route1
Target: target1
m3
INVITE route2
Target: target 1
m4
INVITE target2
Target: target 2
m5
INVITE route3
Target: target2
Where the History-Info header is used, an example the signalling sequence according to FIG. 2 is as follows:
m1
INVITE
target1
m2
INVITE route1
History-Info:
<target1>;index=1; targetentry,
<route1>;index=1.1
m3
INVITE route2
History-Info:
<target1>;index=1; targetentry,
<route1>;index=1.1
<route2>;index=1.1.1
m4
INVITE target2
History-Info:
<target1>;index=1; targetentry,
<route1>;index=1.1
<route2>;index=1.1.1
<target2>;index=1.1.1.1;targetentry
m5
INVITE route3
History-Info:
<target1>;index=1; targetentry,
<route1>;index=1.1
<route2>;index=1.1.1
<target2>;index=1.1.1.1;targetentry
<route3>;index=1.1.1.1.1
In another History-Info header embodiment, an example the signalling sequence according to FIG. 2 is as follows:
m1
INVITE
target1
m2
INVITE route1
History-Info:
<target1>;index=1; targetentry,
<route1>;index=1.1
m3
INVITE route2
History-Info:
<target1>;index=1; targetentry,
<route1>;index=1.1
<route2>;index=1.1.1
m4
INVITE target2
History-Info:
<target1>;index=1; [Note the target entry tag has been removed]
<route1>;index=1.1
<route2>;index=1.1.1
<target2>;index=1.1.1.1;targetentry
m5
INVITE route3
History-Info:
<target1>;index=1;
<route1>;index=1.1
<route2>;index=1.1.1
<target2>;index=1.1.1.1;targetentry
<route3>;index=1.1.1.1.1
Referring to FIG. 3 , there is illustrated schematically a node for use in a communications network. The node 6 could be, for example, a SIP proxy node in an IMS network, such as a CSCF. The node 6 has a receiver 7 for receiving a SIP message, and a processor 9 for rewriting the Request-URI header in the SIP message and adding information (either a new target header or tagging entries in the History-Info header as described above). The node further comprises a transmitter 8 for transmitting the SIP message to a further node.
Referring to FIG. 4 , there is illustrated schematically a terminating node, such as a UE. The terminating node 10 comprises a receiver 11 for receiving a SIP message, and a processor 12 for determining whether the contents of the Request-URI header included in the received SIP message are different from the contents of the Request-URI of the message as originally sent. In this way the terminating node can determine the original target address, and use this for executing policies on behalf of the user or services to the user.
EXAMPLES
The following are examples of how the new Target header described above can be used. However, the extended History-Info usage could be used in the following examples in a similar manner.
1. Unknown Aliases:
A single UA may have multiple AoRs associated with it, for example to use as aliases. It would be desirable for the recipient of a call to know which alias the call was addressed to. The P-Called-Party-ID header field (RFC3455) was introduced to address the scenario of unknown aliases, and the new Target header field would also address this issue.
2. Unknown Globally Routable User Agent URI (GRUU)
A GRUU is a URI assigned to a UA which has many of the same properties as the AoR, but causes requests to be routed only to that specific instance. In some circumstances it may be desirable for a recipient of a call to know whether the call was addressed using its GRUU or its AoR. This is a variant of the “Unknown Aliases” problem, and is addressed by RFC3455. The new Target header field also solves this issue for GRUU's used as initial target.
3. Limited Use Addresses
A limited use address is a SIP URI that is created and provided to a UA on demand. Incoming calls are only accepted whilst the UA desires communications addressed to that URI. Limited use addresses are used in particular to combat voice spam. This is another variant of the “Unknown Aliases” problem, and is addressed by RFC3455. The new Target header field also solves this issue.
4. Sub-Addressing
A sub-address is an address within a sub-domain that is multiplexed with other sub-addresses into a single address with a parent domain. This is used, for example, by employees of small companies, or family groups that wish to have separate sub-addresses by which they can be contacted. The sub-addressing feature is not currently available using SIP because a SIP URI parameter used to convey the sub-address would be lost at the home proxy, due to the fact that the Request-URI is rewritten there. This problem is overcome using the new Target header field.
5. Service Invocation
A URI can be used to address a service within the network rather than a subscriber. The URIs can include parameters that control the behaviour of the service. However, when a proxy has re-written the Request-URI to point to the service, there is no guarantee that the Request-URI will not be re-written by a further proxy in the signal path. The new Target header field would solve this scenario as it will retain the original complex URI, containing all the service invocation information.
6. Emergency Services
A key requirement of systems supporting emergency calling is that a SIP INVITE request for an emergency call is ‘marked’ in some way to ensure that the network knows that the SIP INVITE relates to an emergency call, and accord a priority to the SIP signalling. To avoid abuse by attackers, the marking is applied to the target address of the request itself. This mechanism will not work if any of the proxies along the way try to rewrite the Request-URI for the purposes of directing the call to a proxy or UA that will handle the call. However, the new Target header field solves this scenario as it will retain the emergency URN.
7. Freephone Numbers
Freephone numbers allow a user to call a number without being charged. If an intermediate node in the signalling path re-writes the Request-URI, a charging function may not recognize that the user should not be charged for the call. The new Target header field would solve this scenario as it retains the Freephone Number.
Whilst beyond the scope of this specification, it should be noted that the invention reveals to the UA the target address used to contact the UA, which was previously hidden. There may be circumstances in which it would be undesirable to reveal this information to the UA, in which case the home proxy should remove the header (or other indication) containing the target address.
The invention allows corporate networks and receiving UEs to know under which target identity a request was forwarded. Only the relevant target identity need be retained, and not a history of Request URI rewrites. This improves the efficiency of bandwidth usage and processing. Furthermore, the invention does not interfere with the existing routing mechanism and is compatible with home proxies that do not support loose routing. There is no need for entities using the mechanism to have knowledge whether the next hop supports it, and there is no need for the terminating UA to inform its home proxy whether it supports the mechanism or not. The invention does not require the terminal to support loose routing, and so is backwards compatible. In a scenario in which one of the traversed proxies does not understand the mechanism, routing will still succeed as the routing mechanism of SIP itself is not changed. The worst thing that can happen is that a terminating UA might receive incorrect information about the intended target identity by which it has been reached. The Target header might carry information identifying a forwarding party, where the forwarding party does not want to reveal its identity.
The invention is fully backward compatible with MGCFs that use the Request-URI value for mapping and routing towards a PSTN network, according to the interworking procedures described in RFC3398, 3GPP TS 29.163 and ITU-T Recommendation Q.1912.5.
It will be appreciated by the person of skill in the art that various modifications may be made to the embodiments described above without departing from the scope of the present invention. For example, many of the examples provided above use IMS as an example network, but it will be appreciated that the invention applies to any communications network that uses SIP signalling. | A method and apparatus for handling a Session Initiation Protocol message in a communications network. When a network node receives a Session Initiation Protocol message, which comprises Request-URI header, the node rewrites the Request-URI header in the SIP message, and adds information to the SIP message useable by a remote node to determine the current target address of the message. The SIP message is then sent to a further node. In this way, the remote node that receives the message can determine the current target in the SIP message, even if the target has been re-written in the Request-URI as the result of, for example, a translation or re-routing operation. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to teletypewriter machines and more specifically to such machines which can be used on a portable basis without external power.
2. Prior Art
Teletypewriter machines have been in widespread use for more than a quarter of a century. Generally, they have been large, heavy fixed machines located in business offices and used for national and international business transactions. They have served, more recently, as data input and output equipment for computers, i.e., as peripheral equipment.
In recent years there has been an increasing need for remote terminals for teletypewriter systems and for computer networks. The most recent entrants into the portable terminal field (to applicant's knowledge) are the machines manufactured by Micon Industries of Oakland, CA 94607. These machines weigh 6-14 pounds, cost approximately $1,000 and are intended primarily for computer I/O applications. To the best of applicant's knowledge the printer version of the Micon devices weighs 14 lbs. and is motor powered, which raises the machine's weight and power consumption. Further, it uses thermal printing which further increases power consumption and battery capacity requirements.
Attention is also directed to U.S. Pat. No. 3,493,091 (Kapp) which shows multiple solenoids used in shifting a printing head so that one of two type bands thereon is moved selectively, into an operative position. A stepping motor (of relatively high current consumption) is used for moving the printing drum.
SUMMARY OF THE INVENTION
It is one object of this invention to overcome the general disadvantages of problems set forth hereinbefore.
It is an additional object of this invention to provide a teletypewriter which is lightweight, of low power consumption and is particularly well adapted to portable use away from sources of power, such as the power mains found in offices.
Stated succinctly, by eliminating the synchronous motor normally used to provide mechanical power for head shifting and paper feeding and substituting two solenoids which operate only momentarily in accomplishing the required mechanical motion, providing electronic and electro-mechanical control of the printing head motion and printing functions so as to assure consistent font characteristics, and synchronizing related operations by a central electronic clock, a lightweight, portable printing teletypewriter may be realized. It may be provided with storage to simulate the paper tape storage available with present teletypewriting machines, without the attendant weight and power consumption.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features of my invention are set forth in the appended claims. The manner of operation of my invention can best be understood by referring to the following drawings, in which:
FIG. 1 is a cut-away drawing of a teletypewriter according to my invention;
FIG. 2 is a plan view of a keyboard to be used in my invention;
FIG. 3 is a diagram showing the intercoupling of two teletypewriters, according to my invention;
FIG. 4 is a plot of a possible binary encoding scheme for letters and symbols of the keyboard of FIG. 2;
FIG. 5 is a diagram showing the composition of a letter or symbol printed by the teletypewriter built according to my invention;
FIG. 6 is a perspective drawing of a printer timing system utilized in my invention;
FIG. 7 is a perspective view, partially exploded, showing the printing head shifting mechanism, according to my invention;
FIG. 8 is a perspective view of a portion of the head shifting mechanism of FIG. 7:
FIG. 9 is a perspective view, partially exploded, showing the paper advance mechanism according to my invention;
FIG. 10 is a perspective view of a portion of the printing head carriage mechanism, according to my invention;
FIG. 11 is an elevation view of a portion of the head carriage mechanism of FIG. 10;
FIG. 12 is a perspective view of an alternative mechanism for driving the printing head, according to this invention.
FIG. 13 is a block diagram of the electrical and electronic portions of the teletypewriter according to my invention; and
FIG. 14 is a diagram showing certain time-amplitude-frequency relationships utilized in my invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1, teletypewriter 10 includes case 12 with top plate 14 secured to case 12 by bolts, or other securing, means 16. Case 12 carries P-C board 18 on which are mounted the various I-C's 20 utilized in my teletypewriter, as described more fully hereinafter. Carried in cover or top-plate 14 is the keyboard 22 made up, for example, of fourty-two character keys, one shift key, one space key and four memory keys. Paper drum 24, which can be manually rotated by paper-feed knob 26 is positioned adjacent paper slot 30. Slot 30 is provided for the feeding of paper 28 from drum 24 to the outside of teletypewriter 10. Cover 32 encloses the battery compartment in case 12. Various input connectors, such as microphone and speaker connectors 54 and 40, respectively, and indicators are also provided in top-plate 14.
The keyboard 22 is shown in more detail in FIG. 2. The Roman alphabet, Arabic numerals and commonly used symbols are shown, in addition to shift key 34, space key 36 and head return-paper feed key 38. Obviously, other alphabets or syllabaries may be used, for example Katakana or Farsi.
In FIG. 3, acoustic coupling in and out of two, coupled teletypewriters, according to my invention, is shown. Character tones generated within teletypewriter 10 may be taken from jack 40 and feed through loudspeaker 42 to the transmitter 44 of a conventional telephone which is coupled by the regular telephone system trunks to the receiver portion 46 of a second telephone instrument. The tones received by receiver 46 are coupled to a microphone 48, which, in turn, is coupled to a second teletypewriter 50 through connector 54 and, if desired, to an audio tape recorder 52. First machine 10 may be internally powered (i.e. battery operated) and second machine 50 may be operated from the a.c. mains.
The binary addresses of the characters of keyboard 22 are shown in FIG. 4. For example the letter "A" has the address of 000,001. Those addresses in the matrix which show "O"'s are addresses in memory of automatic machine instructions.
The characters utilized according to one embodiment of my invention, are of standard ASCII font such as are generated by MOS chip 3257 which is available from Fairchild Semiconductor Corporation, 464 Ellis Ct., Mountain View, CA 94042.
Each letter is formed within a 7×5 dot matrix, such as is shown in FIG. 5. In this particular embodiment the printing is by means of electrical discharge from a 35-pin head to be described more fully hereinafter. The total horizontal space assigned to a character is, for example, 2.4 mm. If that space is divided into 9 equal segments the results are as shown in FIG. 5, with five spaces assigned to character formation, one to "ready-print" information and four to blank space.
To keep these spaces equal in width despite speed variations in the driving mechanism a timing wheel 60 is provided. It has six slots 62 spaced 40° apart over two-thirds of the periphery of wheel 60. These slots permit passage of light from light-source 64 to photo-sensor 66. Thus, as wheel 60 rotates in response to the depression of letter or character keys, wheel 60 rotates through 360° and generates six "on" periods at the output terminals 68, 70 of photo-sensor 66. These "on" periods control when discharge may occur from the dot-matrix discharge head 72 (see FIGS. 9, 10, 11, 12) and tend to produce equal spacing of rows 74 in dot matrix 76 of FIG. 5, despite speed variations in the electro-mechanical drive to the printing head.
The overall head-moving electro-mechanical system, with low power consumption, is shown in FIG. 7. In FIG. 7, solenoid 80 is the prime-mover for the system which moves printing head 72. When solenoid 80 is energized through leads 82 and 84 in response to a character or space key's being depressed in keyboard 22 plunger 83 moves to the right (in the direction of arrow 88) in FIG. 7, carrying with it rod 90 which drives cam assembly 92 and pitch pin 94 causing pitch rotor 96 to move an angular amount (60°) equivalent to one pitch distance in the direction of arrow 98. Pitch wheel 100, which is fixed to a common shaft with pitch rotor 96, is stopped accurately at one pitch-equivalent motion by pitch cam-stopper 102. Pawl 104 engages gear 106 to prevent its reverse rotation. Support bearings 101, 103 and 105 are also provided.
The ratio of the gear train including gears 108, and 110 and pinion 112 is such as to produce one, 360° rotation of pinion 112, (and, hence of worm 114) for each one pitch movement of rotor 96. Such one, 360° rotation of worm 114 advances printing head 72 one letter space (about 2.4 mm), by reason of the engagement of tracking pin 116 in the track of worm 114.
The details of the head driving by screw or worm 114 may be seen more clearly in FIG. 8. Foot 120 of head assembly 122 (which includes printing head 72 and tracking pin 116) rides in rail 124 (supported by roller 202). Tracking pin 116 engages helical groove 126 in worm or screw 114. When worm 114 rotates 360°, head assembly 122 is moved a total of one letter space (to the right in this drawing). At the same time it is moving, head 72 is energized according to a predetermined pattern set by the key which was depressed in keyboard 22.
Timing wheel 60 (See FIG. 6) permits electrical discharge from pins 130 when slots 62 are aligned with the light path from light source 24 to sensor 66 (FIG. 6). An appropriate pattern is burnt onto aluminum (or other conductor) backed paper 132.
The return of plunger 82 (FIG. 7) to its original position following de-energization is assured by spring 140 and by the fact that there is cam-coupling (not solid coupling) between shaft 90 and pitch rotor 96.
The apparatus by which the sole remaining electromechanical drive element (solenoid 158) effects all remaining necessary mechanical motion is set forth in FIGS. 9, 10 and 11.
In FIG. 9, yoke 150, when in operating position, engages, in releasable fashion, pins 152 and 154 on plunger 156 of solenoid 158 and is free to rotate about shaft 160 over which it is positioned. Ratchet pin 162 moves in concert with yoke 150 and, if solenoid 158 is energized, pin 162 engages gear 164 in feed wheel 166. Wheel 166 is fixed on shaft 160 or an extension thereof, and motion of wheel 166 by reason of engagement between pin 162 and gear 164 and energization of solenoid 158 results in rotation of shaft 160 and rollers 170 (in combination with roller 172) causing paper 132 to be fed out by a length equal to the desired distance between printed lines.
When paper feeding is occurring it is desirable to disengage head 72 from the paper 132. To achieve that end, solenoid 158, which also activates the paper feeding, is utilized. Pin 180 connects plunger 156 pivotally to swing-lever 182 which is pivoted about central hole 184. Pivot pin 186, in the remote end of swing-lever 182, is coupled through linkage 188 to rail 124. (See also FIGS. 8, 10 and 11). Foot 120 of head assembly 122 (FIG. 8) rides in rail 124. When solenoid 158 is energized to feed paper 132, swing-lever 182 pivots about point 184 causing rail 124 to move away from worm 114, disengaging tracking pin 116 from the grooves of worm 114 and pivoting head assembly 122 around rod 190 (FIG. 11).
The return of head assembly 122 to the left margin during the paper-feed step is assured by spring 200 attached to assembly 122 and biasing it to the left, as shown in FIG. 10. Foot 120 of head assembly 122 is surrounded by roller 202 which slides in rail 124.
Linear solenoids 80 and 158 may be replaced by rotary solenoids.
To replace solenoid 80 by a rotary solenoid the structure of FIG. 12 may be utilized. In FIG. 12 worm 126 of FIG. 8 has been replaced by toothed belt 210 which receives its motivation from rotary solenoid 212 through a gear train 214. Tracking pin 116 is positioned between two adjacent teeth, for example teeth 216 and 218, and is moved thereby as belt 210 moves.
FIG. 13 is an overall block diagram of the electronic portion of the teletypewriter incorporating my invention.
The keyboard 250 is a standard ASCII board. Its key matrix is coupled to an ASCII encoder 252 of the type widely available, as for example, from Fairchild Semiconductor Co., 464 Ellis Ct., Mountain View, CA. 94042.
The encoded signals enter buffer register 254 from which they may be read out to FSK modulator 256 and thence to loudspeaker 258 for coupling to a telephone transmitter, as shown in FIG. 3. Alternatively they may be read out to character generator and output drive 260 which may be Fairchild MOS Type No. 3257.
Instead of immediately transmitting each character signal as it is generated it may be stored in RAM 262 which is made up of six Fairchild Type 2102 I-C chips. This gives 1000 letter storage. Such capability replaces the paper tape capability of standard teletypewriters.
Solenoids 80 and 158 get their printing instructions either directly from buffer register 254 or from microphone 264 acoustically coupled to a telephone receiver and electrically coupled to demodulator 266 which translates the received FSK signal 268 (shown in FIG. 14) into "zeroes" and "ones" (binary signals) to operate the logic circuits and, ultimately, drive solenoids 80 and 158 to print alphanumeric information. A central clock 270 maintains synchronism in the circuit. This clock may be included in demodulator chip 266 or in control circuit 272.
In FIG. 14, pulse signal 280 translates into a frequency-shift signal 282 with "ones" becoming high frequency signals (say, 2000 Hz) and "zeroes" being low frequency signals (say 500 Hz).
While a particular embodiment of my invention has been shown and described, it will be apparent to one skilled in the art that variations and modifications may be made without departing from the spirit or scope of my invention. It is the intention of the appended claims to cover all such variations and modifications. | By utilizing as the driving elements for paper positioning and printing head positioning two solenoids, only, with appropriate electrical and mechanical timing control apparatus to assure synchronization of printing and related functions a low cost, portable, low weight, low-power-consumption teletypewriter can be realized. | 1 |
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