FLUID PRESSURE APPARATUS

Abstract: A fluid pressure apparatus to which a plurality of machines are connected via a manifold and which is provided with a controller circuit including a memory that stores control steps. Each controller circuit operates control valves and sensor in accordance with an operation instruction from a sequencer to ascertain the control condition and judge the occurrence of a failure. Therefore, a high-degree control operation can be carried out without laying an overload on the sequencer.

Description: TECHNICAL FIELD The present invention relates to a fluid pressure apparatus wherein, when individual fluid pressure apparatuses connected to one another in plural form are used, controlling means such as controllers are attached to the corresponding fluid pressure apparatuses so as to cause a sequencer to effect only timing control and the like on the fluid pressure apparatuses, so as to detect malfunctions or the like, thereby performing advanced control. BACKGROUND ART A fluid pressure apparatus for supplying and cutting off a fluid pressure to a working device has heretofore been used under various circumstances. For example, a vacuum unit for supplying a vacuum pressure comprises an ejector, a valve for supplying and cutting off the vacuum pressure, etc., all of which are provided inside the vacuum unit. The vacuum unit is coupled to a suction pad, or the like, used as a working device and operated in response to a signal supplied from a sequencer to supply the vacuum pressure to the suction pad, thereby attracting and feeding a workpiece. In the vacuum unit referred to above, it is desirable to prevent the workpiece from falling from the suction pad due to a failure in operation of the ejector by confirming all the operated states. That is, there is now a demand for a system in which operating conditions of an ejector and valve can be rapidly confirmed to detect a failure in operation, which is caused by clogging or the like, and for automatically carrying out a process for coping with such a trouble. However, when such a process is carried out by a sequencer, a problem arises in that when vacuum units are connected to one another by manifolds, the burden imposed on the sequencer is too great to adequately carry out discrete control, such as ON/OFF timing control or the like for each vacuum unit. It is known from the document JP-A-63-154 900 to provide the components of a vacuum generating unit, such as a vacuum generating source, a solenoid operated directional control valve, an air supply source, a flow regulating valve, etc. with a substantially identical shape. At least two of those components are integrally connected by an arbitrary selection. If necessary, a plurality of the integrally connected fluid devices is linearly and proximately provided through a manifold. While the number of processes of piping operations can be reduced, similar problems as mentioned above can arise. The present invention is intended to solve the above problem. It is an object of the present invention to provide a fluid pressure apparatus capable of reducing the burden imposed on a sequencer, and for carrying out discrete control. DISCLOSURE OF THE INVENTION The fluid pressure apparatus of the present invention as set forth in claim 1 can provide advanced control without imposing an excessive burden on a sequencer. When a plurality of fluid pressure apparatuses are connected to one another by manifolds or the like, controlling means, each having a memory inputted with a control step, are attached to the respective fluid pressure apparatuses, and signals detected by detecting means are compared and analyzed to thereby make a decision whether a trouble or the like exists and to display a result thereof. Further, when electrical wires are attached to the inside of the fluid pressure apparatus, connectors comprised of conductive elastic bodies are mounted to their corresponding connecting portions. It is thus unnecessary to consider the accuracy of the position at each connecting portion. Moreover, each of the manifolds has standardized surfaces for causing fluid passages to communicate with each other, and a plurality of different types of fluid pressure devices can be connected to each manifold. It is therefore possible to reduce the space occupied by the whole fluid pressure apparatus, and thus effectively make use of available space. In a fluid pressure apparatus to which blocks having different functions from each other are coupled together, fluid connecting portions, electric signal coupling portions, and block engaging means for connecting the blocks to each other are provided on connecting or joint surfaces thereof or at the same places near such joint surfaces. It is therefore possible to easily connect desired blocks to each other. There is also provided a cover for covering fluid pressure devices, such as a solenoid-controlled or electromagnetic valve devices, ejectors, etc., and integrating them in appearance. Thus, the design of the devices can be decided without being restricted by functions or the like of the fluid pressure devices. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view showing a vacuum unit according to a first embodiment of the present invention; FIG. 2 is a fluid circuit diagram showing the vacuum unit shown in FIG. 1; FIG. 3 is a circuit diagram illustrating a controller of the vacuum unit shown in FIG. 1; FIG. 4 is a view for describing the control of the vacuum unit shown in FIG. 1; FIG. 5 is a view for describing the electrical connections between a vacuum generating unit with a local controller and a sequencer, according to a second embodiment of the present invention. FIG. 6 is a view for describing the electrical connections between a vacuum generating unit with a local controller and a sequencer, according to a third embodiment of the present invention; FIG. 7 is a view for describing the electrical connection made to rubber contactors employed in the third embodiment shown in FIG. 6. BEST MODE FOR CARRYING OUT THE INVENTION A fluid pressure apparatus according to the present invention will hereinafter be described in detail with reference to the accompanying drawings. In the following embodiments, vacuum units are all described as illustrative examples. It should however be borne in mind that this invention is not limited only to vacuum units. The present invention can also be applied to other fluid pressure apparatuses. As shown in FIGS. 1 and 2, a vacuum unit 50 basically comprises a manifold 52, comprising a filter unit 54, an ejector unit 56, a valve unit 58 and a control unit 60, all of which are provided on the manifold 52. The manifold 52 has a feed passage 62, a discharge or exhaust passage 64, and an exhaust passage 66 for a pilot valve, all of which are defined therein. Further, the manifold 52 also includes a connector 68 formed by stacking conductive elastic bodies for electrical connection and non-conductive elastic bodies one after the other. The respective passages 62, 64 and 66 and the connector 68 are provided so as to be mutually connected to the manifold 52. Further, they are also connected to fluid devices mounted on an upper portion of each manifold 52. The filter unit 54 mounted on the manifold 52 has a vacuum port 70 in which a one-touch joint has been incorporated therein so that the vacuum port 70 is connected to a working device such as a suction pad or the like. The vacuum port 70 has passages defined therein, which communicate with a pressure sensor 104, an ejector 80, etc. Further, hydrophobic filters 72 and 74, such as porous fluorine-contained resin membranes, etc., and check valves 76 and 78 are provided so as to extend along their corresponding passages. The filter 72 is so constructed that the elements thereof are shaped in the form of a cartridge, and the cartridge catches dust. As indicated by a two-dot chain line, the filter 72 is also constructed in such a manner that a filter cover thereof can be taken off, and a region or position for the filter 72 can be changed as needed. The check valve 78 closes when a vacuum breakage has occurred in the suction pad. At this time, the check valve 78 prevents a state of vacuum pressure from being gradually released due to the entry of a fluid through a small hole defined in the check valve 78, for example, and prevents the pressure sensor 104 from continuously outputting a signal indicative of an attracted state. The ejector unit 56 mounted to an upper portion of the filter unit 54 is provided with an ejector 80. The valve unit 58 mounted to an upper portion of the ejector unit 56 has a feed valve 82 and a vacuum break valve 84. The control unit 60 mounted to an upper portion of the valve unit 58 has a pressure-switch operation indicating lamp 86, condition setting switches 88 such as a sensors, etc., and a pilot valve operation indicating lamp 90. Inside of the control unit, an auxiliary control substrate 92 for a memory and a timer, a flow control valve 94, a display LCD 96 disposed above the flow control valve 94, an LCD disposed below the display LCD 96, a substrate 98 for the switches, a main control substrate 100, a pressure sensor substrate 102, a pressure sensor 104, a hydrophobic and water-preventing filter 106, solenoid-controlled pilot valves 108a and 108b, and a valve driving/controlling substrate 110 are provided. A controller circuit 111 of the control unit 60 is constructed as shown in FIG. 3. More specifically, the controller circuit 111 comprises a memory 112 comprised of, for example, a ROM for storing therein working procedures, timer settings, condition settings, etc., and the like via switches 88. The switches 88 correspond to a setting means, a CPU 114, I/O units 116a, 116b and drivers 118a, 118b which are respectively disposed between the CPU 114 and the solenoid-controlled pilot valve 108a connected to the controller circuit 111, and between the CPU 114 and the solenoid-controlled pilot valve 108b connected thereto, and an I/O unit 122 provided between the CPU 114 and a pressure sensor circuit 120 provided inside the pressure sensor 104. These components may be incorporated into a single substrate or may be divided so as to be disposed on a plurality of substrates. Alternatively, the majority of these components may be shaped in the form of one chip or may be constructed of a small number of dedicated ICs, ASICs, hybrid ICs or the like. Further, a flexible substrate or the like may be used as the substrate which can be bent to improve spatial efficiency. The electrical connection between each of the substrates and each unit is made by the connector 68 made up of the conductive elastic bodies. However, the electrical connection therebetween may also be performed by means other than the connector 68, such as using a connector or the like provided with male/female pins. The vacuum unit 50 constructed as described above is operated in the following manner. Specifically, an operator first uses the switches 88 in accordance with working conditions to input setting conditions to the memory 112 of the controller circuit 111. In accordance with the conditions set in the memory 112, an electric signal is then supplied to the solenoid-controlled pilot valve 108a via the CPU 114, the I/O unit 116a and the driver 118a, so as to energize the solenoid-controlled pilot valve 108a and thereby enable the feed passage 62 of the manifold 52 to communicate with a pilot chamber of the feed valve 82 so as to open the feed valve 82. Accordingly, the feed passage 62 communicates with the ejector 80 to open the check valve 76 to thereby suck or draw air from the working device such as a suction pad or the like via the vacuum port 70 and the filter 72. The drawn air and the air used in the ejector 80 are discharged from the exhaust passage 64 of the manifold 52. As the pressure sensor 104 made of a silicon diaphragm or the like is easily deteriorated by water, the pressure sensor 104 detects a state of pressure applied to the working device in a state in which water or moisture has been removed by the filters 74 and 106 in order to prevent the pressure sensor 104 from deterioration, and generates a signal for controlling the working device. On the other hand, when a vacuum breakage is to be performed, the controller circuit 111 sends a signal to the solenoid-controlled pilot valve 108a to close the feed valve 82 and transmits a signal to the solenoid-controlled pilot valve 108b to open the vacuum break valve 84. Thus, the vacuum port 70, which is in communication with the working device, communicates with the feed passage 62 to thereby release a vacuum pressure having been applied to the working device. At this time, the check valve 78 is closed to prevent damage to the pressure sensor 104, which can occur due to an abrupt variation in pressure. Further, a small hole defined in the check valve 78 gradually releases the working device from the vacuum pressure, and thereby prevents the pressure sensor 104 from generating an improper operation signal. The entirety or a part of the vacuum unit 50 is formed with a transparent plastic. The filters, the ejector, the valves, coils, the control unit 60, the passages, a silencer, wires, etc. employed in the vacuum unit 50 can be visually inspected and maintained. Further, a unit to which the vacuum pressure is fed from an external vacuum pump can be constructed as the vacuum unit 50 by removing the ejector unit 56 from the vacuum unit 50, and using the feed valve 82 as a vacuum directional control valve, i.e., as a vacuum selector. A description of easing the burden imposed on the sequencer due to the above-described operation of the vacuum unit 50 and individually controlling the components will be made with reference to FIGS. 2 through 4. Incidentally, the operation of the vacuum unit 50 is performed for the purpose of attracting and feeding a workpiece by a suction pad or the like. The sequencer first sends an operating command or instruction to the controller circuit 111 of the vacuum unit 50. The controller circuit 111 causes the CPU 114 to transmit an operation signal to the solenoid-controlled pilot valve 108a via the I/O unit 116a and the driver 118a in accordance with the conditions set in the memory 112. Immediately after the transmission of the operation signal to the solenoid-controlled pilot valve 108a, the CPU 114 also sends an operation signal to the pressure sensor 104 in the same manner as described above. Thus, compressed air is introduced into the ejector 80 provided inside the vacuum unit 50 from the feed valve 82 to thereby produce a vacuum pressure, which is in turn supplied to the suction pad via a tube. During this period, the pressure sensor 104 detects or measures the vacuum pressure in the vacuum port 70, and information about the measured vacuum pressure is displayed on the LCD 96. Thereafter, the pressure sensor 104 supplies the information to the CPU 114 in succession. The CPU 114 compares the information with each of a predetermined vacuum trouble limit and an attraction-confirmative vacuum pressure. The information may be displayed on a display circuit as an alternative to the CPU 114. Here, the predetermined vacuum trouble limit is a vacuum pressure in which the attraction and feeding of the workpiece by the vacuum unit 50 can be impeded. If the vacuum pressure in the vacuum port 70 does not meet the predetermined vacuum trouble limit, then a trouble condition is displayed in the LCD 96 of the control unit 60, and a signal indicative of the trouble is sent to the sequencer simultaneously with the display thereof. The attraction-confirmative vacuum pressure is a vacuum pressure used to confirm that the workpiece has been attracted by the suction pad supplied with the vacuum, and that the vacuum pressure in the vacuum port 70 has reached a desired vacuum pressure. If it is decided based on the result of comparison by the CPU 114 that the detected vacuum pressure of the vacuum port 70 exceeds the attraction-confirmative vacuum pressure set in the memory 112 in advance, then the LCD 96 performs an attraction confirmative display. Thereafter, when the controller circuit 111 receives a work-movement confirmative signal based on a signal supplied from a switch or the like provided on a conveying device such as a cylinder or the like, and after the elapse of a predetermined time interval set by a timer for the feed valve in the memory 112, the CPU 114 sends a signal to the feed valve 82 for stopping the operation thereof in accordance with a program set in the memory 112. The feed valve 82 stops operating in response to the signal supplied from the CPU 114, so that the generation of the vacuum pressure in the ejector 80 is stopped. Simultaneously, the CPU 114 sends a command break to the vacuum break valve 84 to actuate to supply compressed air to the suction pad via the vacuum port 70. As a result, the time required to feed air is controlled by a timer or the like, and vacuum breakage is performed based on a signal supplied from a switch or other external device. During this period, the pressure sensor 104 measures the pressure in the vacuum port 70. Further, information about the measured pressure is displayed on the LCD 96 and sent to the controller circuit 111 in succession. The CPU 114 of the controller circuit 111 compares the information with a breakage confirmative air pressure which has been preset in the memory 112. Here, the breakage confirmative air pressure is an air pressure which is used to confirm that the work has been completely separated from the suction pad, and that an air pressure in the vacuum port 70 has reached the atmospheric pressure. When the air pressure falls below the breakage confirmative air pressure which has been preset in the memory 112, the LCD 96 makes a breakage confirmation display, and at the same time the CPU 114 sends an operation stop signal to the vacuum break valve 84 and the pressure sensor 104. As a result, the vacuum break valve 84 and the pressure sensor 104 stop operating. Thereafter, the controller circuit 111 sends a series of operation completion signals to the sequencer to thereby finish all of the attracting and feeding operations by the vacuum unit 50. In the present embodiment, as shown in FIG. 4, a portion of the control of the sequencer is taken care of by the controller circuit 111 so that the burden imposed on the sequencer is reduced. Control of an increased number of vacuum units connected to one another by a manifold is made possible by the reduction in the burden imposed on the sequencer. Alternatively, assuming the control capacity of the control unit 60 is sufficient, it is then possible to perform fine control of each vacuum unit, which has been unattainable in the prior art. A system for controlling a plurality of control units of this type will be described below as a second embodiment with reference to FIG. 5. FIG. 5 shows a vacuum apparatus 154 comprising a plurality of vacuum generating units 152a through 152e with local controllers, which are connected to one another by a manifold 150. Vacuum generating unit 152a with a local controller, which has been placed on the manifold 150, is made up of a block 156a having an ejector, a compressed-air feed valve 158a, a vacuum break valve 160a, an attraction confirming switch 162a and a controller 164a. The peripheral devices of the vacuum generating unit 152a with the local controller, i.e., the compressed-air feed valve 158a, the vacuum break valve 160a and the attraction confirming switch 162a which is used with either a pressure sensor or a pneumatic bridge, respectively have signal lines or conductors 166a and are individually connected to the controller 164a. The controller 164a has a signal terminal 168a attached to an upper portion thereof and is connected to signal lines 172 via a connector 170a. The other vacuum generating units 152b through 152e with the local controllers are constructed in the same manner as described above. The signal terminals 168a through 168e of the respective controllers 164a through 164e are connected to one another through the connector 170a and connectors 170b through 170e, and through the signal lines 172. Further, the signal terminal 168e provided at an end of the manifold 150 is connected to an unillustrated sequencer. The signal lines 172 are divided into address signal lines which are used to identify the signals supplied from the sequencer and the individual controllers 164a through 164e, and into data signal lines which are used to transmit information. Each of the respective controller-unit pairs has an address setting means. Thus, the lines which are used for the signals produced from the controllers 164a through 164e can be in the form of a bus line by determining or establishing the communication between the sequencer and the individual controllers 164a through 164e. Further, the lines used for the signals referred to above may also be in the form of a single line by setting complete serial communications between the sequencer and each of the controllers 164a through 164e. Further, the transmission of wireless, light, radio waves or similar space transmission may be performed between such a communicating means and the bus line, as well as the signal conductor, from both inside and outside of the apparatus. In the present embodiment, each of the controllers 164a through 164e is disposed between the sequencer and each of the peripheral devices of the vacuum generating units 152a through 152e. Thus, in spite of multiple operations performed by the manifold 150, the burden on the sequencer is reduced and the signal lines are greatly reduced due to the shaping of the signal lines 172 in the form of the bus line. Further, a third embodiment will be described below with reference to FIG. 6. FIG. 6 shows vacuum generating units 200a through 200c with local controllers, each of which is made up of blocks having separate functions. The vacuum generating unit 200a is formed by stacking on top of a manifold block a filter block 204a, an ejector block 206a, a pressure sensor block 208a, a valve block 210a having a compressed-air feed valve and a vacuum break valve, and a control block 216a having a conditions setting portion 212a and a display 214a, wherein the stacked portion is connected to the manifold block 202a by a connecting member 218a. Each of the blocks 202a, 204a, 206a, 208a, 210a and 216a has an electrical connecting portion 220a comprised of a rubber contactor. As shown in FIG. 7, the rubber contactor is formed by stacking conductive elastic bodies 222 and non-conductive elastic bodies 224 one after the other. The electrical connection between the rubber contactor constructed in the above-described manner and adjacent substrates 226 and 228 for the adjacent blocks are established by interposing the rubber contactor between the substrates 226 and 228. Each of the remaining vacuum generating units 200b and 200c is constructed in the same manner as described above. The vacuum generating units 200a through 200c are connected to the blocks adjacent thereto by pairs of locking plates 230a through 230c of the manifold blocks 202a through 202c respectively. When the vacuum generating units are juxtaposed and connected to one another in this way, the manifold block 202a is connected to an unillustrated compressed-air feed source at a side surface thereof which is not in use for connecting other manifold block. On the other hand, a wiring block 232 is connected to the vacuum generating unit 200c and coupled to an unillustrated sequencer through a signal line 234. The wiring block 232 provides parallel communications with each local controller on a pneumatic device or apparatus via an electrical connecting portion 220a using a serial/parallel converter. Further, the wiring block 232 provides communications with a sequencer and an external control device using several signal lines 234. The wiring block 232 also has a display for displaying a state of operation thereon and a signal terminal both of which are mounted thereon. In the present embodiment, the wiring block 232 serves as an intermediate controller for controlling communication with each of the control blocks 216a through 216c. However, the wiring block 232 may also carry out setting, programming, information display and integrated control of each controller. Each of the controllers referred to above, which can reduce a burden imposed on the sequencer, may have various types and functions, not limited to those described in the present embodiment. First of all, as means for realizing the functions of the controller, there may be: a hardware such as an electrical circuit or the like; a programmable software combined with a CPU, memory, etc.; and a combination of both for setting by programs various deciding items to be set, etc. Further, as controlling methods or methods of setting sensors, addresses, programs, etc., there may be: directly setting the above items using dip switches, rotary multi switches, wire matrix switches, etc., and a trimmer or the like on each controller; connecting programming devices such as a teaching box, etc. to each control unit to thereby effect a setting or control process; collectively downloading data such as programs, etc. from a master control apparatus such as a sequencer upon starting, for example; and a direct connection of a storage device such as a ROM, a memory card or the like to thereby effect a desired setting or control process; etc. Next, as methods of displaying information supplied from controllers, there may be: directly displaying information by controllers such as an LCD, an LED, a lamp, a buzzer, etc.; concentratively performing information displays made by a plurality of controllers such as manifolds, etc. using a display unit; and a concentrative and collective display using a master control apparatus such as a sequencer or the like; etc. Further, as functions for controlling the fluid pressure apparatus, there may be: various displays for diagnosing failures in the fluid pressure apparatus illustrated in the present embodiment, and for determining faulty parts at the time of the failure of the fluid pressure apparatus, and the classification of faults and a display for replacing parts to be replaced such as a silencer, a filter, etc. Moreover, there also may be functions such as a self-diagnosis of faults by the controller itself, such as program errors or sequencer errors or the like and self-resetting of the controller; a self-recovering function effected based on reprograms, etc.; a safety stoppage for preventing a workpiece from falling during various fault conditions, such as failure in fluid pressure, stoppage of a power supply, prevention of a fluid from outflow, and the like; recovery of functions for a fluidics system by safety stoppage for preventing of a workpiece from falling during various condition such as failure in fluid pressure, stoppage of a power supply, prevention of a fluid from outflow, and the like, and by providing auxiliary devices such as a power supply, a sensor, a circuit, etc., and selecting any one of them; an address setup made upon execution of either serial or parallel communications with a master control apparatus such as a sequencer or the like; an attachment of a priority to each communication with the master control apparatus; a timer function for setting a time interval required to operate or actuate an operation valve, a break valve or the like; a function for sensing the state and kind of workpiece using a sensor, and controlling the pressure and flow rate of a fluid to thereby correspond to the capability of the fluid pressure apparatus; etc. Even in the case of a combination of a control apparatus such as a sequencer or the like, a controller, and a fluid pressure apparatus, there is considered, for example, a method of hierarchizing control structures based on intermediate (management) control units for controlling a plurality of fluidics systems by a single controller and managing communications between a plurality of controllers by setting the controllers, programming the controllers, or providing information displays for the controllers. INDUSTRIAL APPLICABILITY As has been described above, when a plurality of fluid pressure apparatuses according to the present invention, are connected to one another and controlled by the sequencer, the individual fluid pressure apparatuses are provided with controlling means, and a trouble diagnosis or the like is performed by the controlling means, and suited for use in an automated conveyor line or a production line, without imposing any burden on a sequencer.

Claims: A fluid pressure apparatus for supplying and cutting off positive or negative fluid pressure to a fluid pressure controlled device connected to said apparatus, comprising: detecting means including a sensor (104) for detecting an internal state of said fluid pressure apparatus; control means (111, 216); and display means (96, 214) for displaying a status of said fluid pressure apparatus thereon; characterized in that: said fluid pressure apparatus is constituted of a plurality of blocks having different functions; said detecting means, said control means (111, 216) and said display means (96, 214) are all arranged in one of said blocks, said fluid pressure apparatus comprising another of said blocks having at least one joint surface for connection to another adjacent fluid pressure apparatus block; and said control means (111, 216) includes a memory means (112) in which control steps for said block are stored locally. The fluid pressure apparatus as claimed in claim 1, further comprising: at least one directional control valve (108a) for switching between supply and cut-off of a fluid to said fluid pressure controlled device, wherein said control steps stored locally in said control means (111) control an operation of said at least one directional control valve (108a). The fluid pressure apparatus as claimed in claims 1 or 2, wherein each of said blocks (156, 204, 206, 208, 210, 216) forming said fluid pressure apparatus has at least one connector (164, 220) made of conductive elastic bodies (172, 222), and wherein an electrical connection between adjacent blocks is made through the conductive elastic bodies included in said connector. The fluid pressure apparatus as claimed in claim 3, wherein each of the blocks forming said fluid pressure apparatus has a connector (220) formed by conductive (222) and non-conductive (224) elastic bodies, and wherein the electrical connection between the adjacent blocks is made through the conductive elastic bodies included in said connector. The fluid pressure apparatus as claimed in claim 3 or 4, wherein each of the blocks constituting said fluid pressure apparatus has a connector (200) formed by stacking conductive (222) and non-conductive (224) elastic bodies one after the other, and wherein the electrical connection between the adjacent blocks is made through the conductive elastic bodies included in said connector. The fluid pressure apparatus as claimed in any one of claims 3 through 5, wherein each of the elastic bodies forming said connector of each of the blocks comprised in said fluid pressure apparatus is made of either a synthetic resin or rubber. The fluid pressure apparatus as claimed in any one of claims 1 through 6, wherein said fluid pressure apparatus is a vacuum apparatus (50, 154). An arrangement comprising a plurality of fluid pressure apparatuses as defined in claim 1 or 2 connected with a sequencer said sequencer being externally attached to at least one of said fluid pressure apparatuses (152, 200), wherein said controller (111) and said sequencer are connected so as to communicate signals therebetween. The arrangement as claimed in claim 8, wherein said plurality of fluid pressure apparatuses (152, 200) are connected to one another by manifolds (150, 202), said fluid pressure apparatuses (152, 200) further being connected to each other to communicate signals to and from adjacent apparatuses. The arrangement as claimed in claim 8 or 9, further comprising electrical wires disposed inside said at least one fluid pressure apparatus for providing electrical connections between said control means (111) and said sequencer.

Inventors: NAGAI SHIGEKAZU, SAITOH AKIO, SUZUKI MASAHIKO, NAGAI, SHIGEKAZU, SAITOH, AKIO, SUZUKI, MASAHIKO, NAGAI, Shigekazu, SMC K K Tsukuba Gijitsu Center, SAITOH, Akio, SMC K K Tsukuba GijutsuCenter, SUZUKI, Masahiko, SMC K K Tsukuba Gijutsu Center
Applicants: SMC KK, SMC KABUSHIKI KAISHA
Application year: 1992
Main classification: F04B49
IPC codes: G05B19, F04F5, F15B13, F16K27, G05D16