JP2007232018A - Valve mechanism, pressurized fluid device operation maintaining mechanism and bellows valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve mechanism for controlling suitably a fluid stream and a pressurized fluid device operation maintaining mechanism equipped with the valve mechanism, which maintains suitably an operation of a pressurized fluid device at a given case and further to provide a bellows valve as a pressurized fluid device equipped with the operation maintaining mechanism. <P>SOLUTION: The valve mechanisms 80, 90 are equipped with: valve main bodies 81, 91; valve bodies 82, 92; compression springs 83, 93; piston rods 84, 94; and pistons 85, 95, respectively. First ports 816, 916 are coupled to a pressurized fluid supply means, second ports 817, 917 are coupled to a first cylinder chamber and a second cylinder chamber, respectively, which are inside piston cylinders of the bellows valve, a third port 818 is coupled to a fourth port 919, and a fourth port 819 is coupled to a third port 918. When pressurized air is urgently stopped from being supplied, valve seats 813, 913 are closed in the valve bodies 82, 92, respectively, thus allowing the operation of the bellows valve to be held in a state of its emergency stop. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a valve mechanism that controls the flow of fluid, an operation maintaining mechanism for a pressure fluid device that can maintain the operation of the pressure fluid device in a predetermined case by including the valve mechanism, and a pressure that includes the operation maintaining mechanism. The present invention relates to a bellows valve as a fluid device.

Conventionally, various valve mechanisms have been applied to equipment using fluid. As such a valve mechanism, there is a mechanism that directly opens and closes a flow path, and a mechanism that controls a valve mechanism that opens and closes the flow path. For example, as the former valve mechanism, there is known a bellows valve that prevents the outflow of a fluid having characteristics such as toxicity, volatility, and flammability.
A specific example of such a bellows valve is shown in FIG. In FIG. 1, the bellows valve 100 includes a valve main body 110, and an operating piston rod 130 is slidably supported by a protruding portion 111 of the valve main body 110 via a bonnet portion 120. A disk part 140 as a valve body is attached to the tip of the operating piston rod 130, and this disk part 140 can be brought into contact with and separated from a valve seat 112 provided inside the valve body 110. The road can be opened and closed. A bellows 150 is provided between the disk portion 140 and the bonnet portion 120 in the valve body 110 so as to cover the working piston rod 130. The bellows 150 protects the working piston rod 130 from the fluid flowing in the valve body 110, and can prevent impurities and lubricating oil from flowing into the valve body 110 from the working piston rod 130 side. Yes.

  In addition, a drive unit 160 that moves the piston rod 130 back and forth in the axial direction is fixed to the bonnet unit 120. The drive unit 160 includes a main cylinder 161 and a piston 162 slidably provided in the main cylinder 161, and a base end portion of a piston rod 130 is connected to the piston 162. In the main cylinder 161, a first cylinder chamber 163 and a second cylinder chamber 164 are provided adjacent to each other with the piston 162 interposed therebetween. The first cylinder chamber 163 is provided with a compression spring 165 that urges the disk portion 140 in a direction to close the valve seat 112 via the piston 162 and the piston rod 130. The second cylinder chamber 164 is supplied with pressure fluid from a pressure fluid supply source (not shown) via a pressure fluid introduction path 166 provided in the main cylinder 161.

In such a bellows valve 100, when the pressure fluid from the pressure fluid supply source is not supplied to the second cylinder chamber 164, the disk portion 140 is urged by the compression spring 165 via the piston 162 and the operation piston rod 130. The valve seat 112 is closed, and the flow path in the valve main body 110 is closed.
On the other hand, when the pressure fluid from the pressure fluid supply source is supplied to the second cylinder chamber 164 via the pressure fluid introduction path 166, the piston 162 slides to the first cylinder chamber 163 side, and the disk unit 140 operates. Retreats together with the piston rod 130 to open the valve seat 112. As a result, the flow path in the valve body 110 is opened, and fluid flows through the valve body 110.
When the supply of the pressure fluid from the pressure fluid supply source is urgently stopped for some reason, the disk portion 140 is urged by the compression spring 165 via the piston 162 and the operating piston rod 130, and the valve seat 112 is moved. It is supposed to block.

  Here, the above-described bellows valve 100 is a so-called single-acting bellows valve that supplies the pressure fluid from the pressure fluid supply source only to the second cylinder chamber 164 to advance and retract the working piston rod 130. However, in such a single-acting bellows valve, the urging force of the compression spring 165 must be strengthened in order to reliably close the flow path of the high pressure fluid inside the valve body 110 at the disc portion 140. . As a result, the size of the compression spring 165 is increased, and the size of the main cylinder 161 that accommodates the compression spring 165 is also increased. As a result, the weight of the entire bellows valve increases and the manufacturing cost also increases. There is a problem.

  In this respect, a so-called double-acting bellows valve in which a pressure fluid supply source is connected to both the first cylinder chamber 163 and the second cylinder chamber 164 and the pressure fluid is switched and supplied to any one of the cylinder chambers. The drive unit 160 is compact, and the above problem can be solved. In other words, this double-acting bellows valve has a pressure for supplying pressure fluid into the first cylinder chamber 163 in addition to the pressure fluid introduction passage 166 supplying pressure fluid into the second cylinder chamber 164 to the main cylinder 161. The fluid introduction path is provided. For this reason, the double-acting bellows valve does not need to be provided with the compression spring 165 described above, and the main cylinder 161 is made more compact, so that the entire apparatus can be reduced in weight and cost.

  However, this double-acting bellows valve has no means for restricting the sliding of the piston 162 when the supply of the pressure fluid from the pressure fluid supply source is urgently stopped. Will move to. For this reason, it is necessary to prevent the outflow of harmful fluid by closing the valve seat 112 in the emergency when the fluid of high pressure (for example, 1.0 MPa) is circulating in the valve body 110. Even in such a case, the operating piston rod 130 may easily slide due to the fluid pressure, and the valve seat 112 may be opened. In order to prevent such a problem, a technique for locking the sliding of the working piston rod 130 in the double-acting bellows valve in the emergency is required.

Here, as a technique for locking the working piston rod 130, for example, a brake device that mechanically locks the sliding of the working piston rod 130 is known (see, for example, Patent Document 1).
The brake device described in Patent Document 1 is disposed at a rod end portion of a pneumatic cylinder, and slides on an outer peripheral surface of the substantially cylindrical brake metal fitted on the outer periphery of the piston rod. And a slide bush provided so as to be fitted and movable in a direction different from the axial direction of the brake metal. When pressure is applied from the air supply / exhaust port provided in the brake device, the slide bush moves in a predetermined direction, whereby the brake metal is not pressed against the piston rod and the brake is released. On the other hand, when the air is exhausted from the air supply / exhaust port, the slide bush moves in the reverse direction due to the bias of the spring provided in the brake device, and the brake metal is pressed against the piston rod, and the piston rod is locked. It will be in the state. In this way, the sliding of the working piston rod 130 can be mechanically locked.

As another technique for locking the operating piston rod 130, for example, the one shown in FIG. 2 is known. FIG. 2 shows a brake device 200 disposed at the rod end portion of a pneumatic cylinder, which mechanically locks the sliding of the piston rod, similarly to the configuration described in Patent Document 1 above. It is.
That is, the brake device 200 includes a housing 210 provided with a circular hole 211 through which the operating piston rod 130 is inserted, and a pair interposed between the inner peripheral surface of the circular hole 211 and the outer peripheral surface of the operating piston rod 130. Brake metals 220 and 230 are provided. At this time, the central axis of the working piston rod 130 is eccentric from the central axis of the circular hole 211. Therefore, each of the pair of brake metals 220 and 230 is formed in a substantially semi-cylindrical shape as a whole, and has a wedge shape with a curved cross-sectional shape in the direction perpendicular to the axis. Further, levers 221, 222, 231, and 232 protruding outward in the radial direction are provided at both side ends of the pair of brake metals 220 and 230, respectively. Between the lever 231 of the brake metal 230 facing the lever 221, a compression spring 240 for biasing the levers 221 and 231 in a direction away from each other is interposed. A brake release piston 250 is interposed between the other lever 222 of the brake metal 220 and the lever 232 of the brake metal 230 facing the lever 222.

In such a configuration, as shown in FIG. 2A, when pressurized gas is supplied from a brake release port 260 provided in the brake release piston 250, the levers 222 and 232 are separated from each other by the brake release piston 250. And the compression spring 240 is contracted. In this state, the pair of brake metals 220 and 230 are moved in the direction of arrow A toward the wider side of the eccentric cylindrical space formed by the operating piston rod 130 and the circular hole 211. As a result, a slight gap is formed between the inner peripheral surfaces of both brake metals 220 and 230 and the outer peripheral surface of the working piston rod 130, and the working piston rod 130 can move in the axial direction.
On the other hand, as shown in FIG. 2B, in a state where no pressurized gas is supplied from the brake release port 260, the levers 221 and 231 are moved away from each other by the compression spring 240, and a pair of brake metals 220 and 230 move in the direction of the wedge-shaped tip, that is, in the direction of arrow B. As a result, the inner peripheral surfaces of the pair of brake metals 220 and 230 come into contact with the outer peripheral surface of the working piston rod 130, and the movement of the working piston rod 130 in the axial direction is restricted.

Further, as another technique for locking the working piston rod 130, for example, one shown in FIG. 3 is known. FIG. 3 shows a brake device 300 disposed at the rod end portion of the pneumatic cylinder, which mechanically locks the sliding of the piston rod, similarly to the configuration described in Patent Document 1 above. It is.
That is, the brake device 300 includes a housing 310 into which the operating piston rod 130 is inserted, and a ring-shaped brake metal 320 that is provided in the housing 310 and is fitted on the outer periphery of the operating piston rod 130. One end side of the outer peripheral edge of the brake metal 320 is supported in the housing 310 so as to be inclined. Further, a compression spring 340 is interposed between the other end side of the outer peripheral edge of the brake metal 320 and a plate 330 provided in the housing 310, and the brake metal 320 is always attached by the compression spring 340. It is biased in a tilting direction.

In such a configuration, as shown in FIG. 3A, when pressurized gas is supplied from a brake release port 350 provided in the housing 310, the brake metal 320 is pushed toward the plate 330 by the pressurized gas. Thus, the cylindrical shaft on the inner peripheral surface of the brake metal 320 is in a state where it substantially coincides with the axis of the working piston rod 130. In this state, a gap is formed between the inner peripheral surface of the brake metal 320 and the outer peripheral surface of the operating piston rod 130, and the operating piston rod 130 can move in the axial direction.
On the other hand, as shown in FIG. 3B, when no pressurized gas is supplied from the brake release port 350, the brake metal 320 is inclined by the bias of the compression spring 340, and the axial direction of the working piston rod 130 It becomes a state which is not orthogonal to. In this state, the inner peripheral surface of the brake metal 320 and the outer peripheral surface of the working piston rod 130 are in contact with each other, and the movement of the working piston rod 130 in the axial direction is restricted.

  As described above, in any of the brake devices described in Patent Document 1, FIG. 2, and FIG. 3, the pressure fluid from the pressure fluid supply source in the double-acting bellows valve is supplied to each air supply / exhaust port and brake release port. If it is set as the structure supplied to 260,350, the action | operation piston rod 130 can be locked in the said emergency.

JP 59-223551 A

However, in each brake device described above, it is premised that the friction of the brake metal acts on the piston rod reliably by the action of the pressure fluid and the bias of the compression spring. There is a risk that the locking operation may be defective due to metal processing quality and wear of the brake metal due to long-term use.
In addition, in each brake device described above, when applied to piston rods having different diameter sizes, since brake metals of respective sizes suitable for the diameter sizes of these piston rods are required, the versatility is poor. There is a risk that.
Further, when each of the above-described brake devices is provided for a double-acting bellows valve, since each brake device itself is large, the double-acting bellows valve, which is compact, is large overall. There is a problem that there is a possibility that it will be converted.

  By the way, a valve mechanism is currently known which is provided on a flow path connecting a pressure fluid supply source and a pressure fluid device and controls the flow of pressure fluid in the flow path. As such a valve mechanism, there is a demand for a valve mechanism that allows the flow of pressure fluid in one direction, prevents the reverse flow in the reverse direction, and allows the reverse flow in the reverse direction as necessary. ing. In addition, a valve mechanism that can connect a plurality of pressure fluid devices to a predetermined state to form a pressure fluid circuit and control the operation of each pressure fluid device to a predetermined state is desired. Under such circumstances, there is a demand for a valve mechanism that can suitably control the flow of pressure fluid even by itself, and that can connect a plurality of pressure fluid devices for a predetermined control purpose by combining a plurality of pressure fluids.

  The present invention provides a valve mechanism that can suitably control the flow of fluid, an operation maintaining mechanism for a pressure fluid device that includes this valve mechanism and that can appropriately maintain the operation of the pressure fluid device, and a mechanism for maintaining this operation. It aims at providing the bellows valve as a provided pressure fluid apparatus.

  The invention according to claim 1 includes a valve body having a pressure fluid introduction chamber, a pressure fluid discharge chamber, and a valve seat provided at a position where the pressure fluid introduction chamber and the pressure fluid discharge chamber communicate with each other. And a valve body that is disposed opposite to the valve seat of the valve body and that can be opened and closed, and is supported by the valve body and biases the valve body in the valve seat closing direction. Urging means, a first port communicating with the pressure fluid introduction chamber of the valve body and introducing pressure fluid from the outside, and a first port communicating with the pressure fluid discharge chamber of the valve body and discharging pressure fluid to the outside. Two ports, a cylinder chamber provided in a position opposite to the valve seat in the valve body with the pressure fluid introduction chamber interposed therebetween, and a cylinder chamber in a sealed state with the pressure fluid introduction chamber, and one end of the valve body The other side is fixed while the side is fixed A piston rod extending through the body introduction chamber to the cylinder chamber in a sealed state and supported by the valve body so as to be slidable in the axial direction is connected to the other end side of the piston rod, A piston slidably provided in the cylinder chamber, and a third port for introducing a pressure fluid into a chamber divided by the piston of the cylinder chamber and opposite to the side where the piston rod is inserted. The valve body is configured to open the valve seat against the biasing means when the pressure fluid introduced from the first port acts on the valve body, and the piston The valve is configured to open the valve body against the biasing means via the rod when a pressure fluid introduced from the third port acts on the piston. It is a structure.

According to the present invention, the flow of the pressure fluid can be suitably controlled even with a single unit, and further, one or a plurality of pressure fluid devices can be controlled to a predetermined state by using a plurality of them.
That is, when the valve mechanism of the present invention is provided alone on the flow path connecting the pressure fluid supply source and the pressure fluid device, the first port is connected to the pressure fluid supply source side, and the second port is connected to the pressure fluid device side. And connect. When the pressure fluid is supplied from the pressure fluid supply source to the first port, the valve body opens the valve seat against the biasing means, so that the pressure fluid is supplied to the pressure fluid device and the pressure fluid device. Can be driven. When the pressure fluid flows backward from the pressure fluid device side to the second port, the valve body is urged by the urging means to close the valve seat, so that the pressure fluid can be prevented from flowing backward. Also, if pressure fluid is supplied to the third port, the piston moves and the valve body opens the valve seat via the rod, so the backflow of pressure fluid from the pressure fluid device side to the second port is required. The control which accept | permits according to can be performed. Therefore, the valve mechanism of the present invention can control the flow of the pressure fluid according to a predetermined purpose even when it is a single unit, and can control the operation of the pressure fluid device to a predetermined state.
When applying a plurality of valve mechanisms of the present invention to a pressure fluid circuit provided with one or a plurality of pressure fluid devices, each of the first to third ports of the plurality of valve mechanisms of the present invention has a predetermined By connecting to the flow path, the operation of one or more pressure fluid devices can be controlled to a predetermined state.
In addition, if the third port is used after being closed with a closing plug, it can be effectively used when it is desired to completely prevent the backflow of the pressure fluid from the pressure fluid device side to the pressure fluid supply source.

  The invention according to claim 2 is the valve mechanism according to claim 1, wherein the pressure fluid introduction chamber is provided with a fourth port connectable to the outside.

According to this invention, since the pressure fluid introduced into the first port can be supplied to both the second port and the fourth port, the first pressure fluid device is driven by the pressure fluid flowing out from the second port, And the 2nd pressure fluid apparatus can be driven with the pressure fluid which flowed out from the 4th port, or it can supply to the 1st thru / or the 4th port in other valve mechanisms. If a plurality of such valve mechanisms are used and each of the four ports is connected to a predetermined state, the number of combinations increases as compared with a valve mechanism having three ports, and more diverse control can be realized.
In addition, if the fourth port is used with an obstruction plug, only the first to third ports will function, and if each of the third and fourth ports is obstructed with an obstruction plug, A valve mechanism is obtained in which only the first and second ports function. That is, since the valve mechanism of the present invention can control the flow of the pressure fluid in various states, it can be installed at various positions on the pressure fluid circuit.

  According to a third aspect of the present invention, two valve mechanisms according to the second aspect are prepared, and each of the two valve mechanisms has a first fluid port connected to the pressure fluid supply means. Each of the second ports is connected to a pressure fluid device driven by pressure fluid from the pressure fluid supply means, and the fourth port of one valve mechanism is connected to the third port of the other valve mechanism. An operation maintaining mechanism for a pressure fluid device, characterized in that it is configured to be connected.

  According to the present invention, when the pressure fluid is supplied from the pressure fluid supply means to the first port of one valve mechanism, the pressure fluid device is driven by the pressure fluid flowing out from the second port, and the fourth The valve seat can be opened to the valve body in another valve mechanism by the pressure fluid flowing out from the port. On the contrary, if the pressure fluid is supplied from the pressure fluid supply means to the first port of the other valve mechanism, the pressure fluid device is driven by the pressure fluid flowing out from the second port and flows out from the fourth port. The valve seat can be opened to the valve body in one of the valve mechanisms by the pressurized fluid. Therefore, when pressure fluid is supplied from the pressure fluid supply means to one valve mechanism, the other valve mechanism is opened, and the pressure fluid from the pressure fluid device passes through the other valve mechanism to the pressure fluid supply means side. Can be distributed. When the supply of pressure fluid from the pressure fluid supply means to one valve mechanism is stopped, the other valve mechanism is closed, and the flow of pressure fluid from the pressure fluid device to the pressure fluid supply means side is stopped. Can be made. Thereby, when the supply of the pressure fluid from the pressure fluid supply source is urgently stopped under some condition, it is possible to realize the control for maintaining the operation of the pressure fluid device in the stopped state.

  According to a fourth aspect of the present invention, in the operation maintaining mechanism for the pressure fluid device according to the third aspect, the pressure fluid device includes a main cylinder and an operation piston slidably provided in the main cylinder, An operating piston rod coupled to the piston and driving a driven portion, and each cylinder chamber partitioned by the operating piston of the main cylinder has a different valve mechanism of the two valve mechanisms. An operation maintaining mechanism for a pressure fluid device, wherein the second ports are connected to each other.

According to the present invention, when the pressure fluid from the pressure fluid supply source is selectively supplied to one of the two valve mechanisms, the pressure fluid is introduced into one cylinder chamber of the pressure fluid device, and the other cylinder The pressure fluid in the chamber is discharged to the pressure fluid supply source side. Therefore, the drive piston can be driven by moving the working piston and the working piston rod in two directions.
When the supply of the pressure fluid from the pressure fluid supply source is urgently stopped for some reason, both of the two valve mechanisms are in the valve-closed state, and the pressure is increased in both cylinder chambers in the main cylinder of the pressure fluid device. Since the fluid does not go in and out, sliding of the working piston can be prevented. Therefore, the position of the working piston in the pressure fluid device can be maintained in the state at the time of the stop, and the drive of the driven part can also be stopped, thereby preventing the sudden operation of the pressure fluid device that the user does not intend at the time of the stop. it can.
The valve mechanism is compact because each part is housed in the valve body, and the pressure fluid device can be prevented from becoming large. Furthermore, since the operation of the operating piston rod in pressure fluid equipment can be stopped without using a brake metal as in the past, the machining quality of each part of the valve mechanism relative to the shape of the operating piston rod becomes a problem, and long-term use Therefore, each part of the valve mechanism is not worn. It can also be applied to any working piston rod with a different diameter size.

  The invention according to claim 5 is a bellows valve for controlling the flow of fluid, which is formed in a tubular shape having open ends in three directions, and the fluid flows inside from one open end to the second open end. A bellows valve body having a bellows valve seat provided opposite to the three opening ends on the channel, and a bonnet portion for closing the three opening ends of the bellows valve body, A disk part provided inside the bellows valve body so as to be able to open and close the bellows valve seat; a bellows provided between the disk part and the bonnet part inside the bellows valve body; and the bonnet part A main cylinder fixed to the outside of the main cylinder, a working piston slidably provided in the main cylinder, a base end portion connected to the working piston, and a tip side of the bellows and An operation piston rod that penetrates the bonnet portion and is connected to the disk portion to drive the disk portion, and an operation maintaining mechanism for the pressure fluid device according to claim 3 attached to the main cylinder. The second port of a different valve mechanism of the two valve mechanisms is connected to each cylinder chamber partitioned by the operating piston of the main cylinder, respectively. .

The bellows valve of the present invention is a so-called double-acting bellows valve, so it is small in size. When the pressure fluid from the pressure fluid supply means is selectively introduced into the first cylinder chamber or the second cylinder chamber, the operating piston In addition, the bellows valve seat can be opened and closed at the disc portion via the operating piston rod. Since this bellows valve is provided with the above-described operation maintaining mechanism, when the supply of the pressure fluid from the pressure fluid supply source is urgently stopped under some condition, both of the two valve mechanisms are in the valve closed state. The flow of pressure fluid in both cylinder chambers of the main cylinder can be stopped. Thereby, since the movement of the working piston and the working piston rod is stopped, the opening / closing operation of the bellows valve seat by the disk portion can be maintained in the state at the time of the stop. Therefore, sudden operation of the bellows valve that is not intended by the user at the time of stoppage can be prevented.
Further, the two valve mechanisms in the operation maintaining mechanism are compact because each part is housed inside the valve body, and the bellows valve can be prevented from being enlarged.
Furthermore, the operation maintenance mechanism can stop the operation of the bellows valve without using a brake metal as in the past, so the machining quality of each part of the valve mechanism relative to the shape of the operating piston rod becomes a problem, and it can be used for a long time. Therefore, each part of the valve mechanism is not worn. It can also be applied to any working piston rod with a different diameter size.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a side sectional view showing a bellows valve and an operation maintaining mechanism according to an embodiment of the present invention.

[Configuration of bellows valve 1]
In FIG. 4, reference numeral 1 denotes a bellows valve. This bellows valve 1 is applied to equipment using fluids in fields such as the petroleum industry and the chemical industry, and has a characteristic such as toxicity, volatility, and flammability. This is a valve mechanism that directly opens and closes a flow path (hereinafter referred to as a controlled fluid).
Note that the bellows valve 1 of the present embodiment is configured such that the pressurized air (pressure fluid) is selectively supplied to one of the first cylinder chamber 514 and the second cylinder chamber 516 so that the disc portion 30 has a bellows valve seat. This is a so-called air-actuated double-acting bellows valve that opens and closes 14.
Such a bellows valve 1 includes a bellows valve main body 10 shown in the lower part of the figure, a bonnet part 20 provided at the upper end of the bellows valve main body 10 in the figure, and a disk part 30 provided inside the bellows valve main body 10. (Driven part) and bellows 40, drive part 50 provided in the upper right of the bonnet part 20 in the figure, and working piston provided between the inside of the bellows valve body 10 and the inside of the drive part 50 The rod 60 and an operation maintaining mechanism 70 provided in the drive unit 50 are provided.

  The bellows valve body 10 is formed in a substantially Y-shaped tube having open ends in three directions, and a flow path forming port 11 (left end in the figure) as one open end and a flow path forming port as a second open end. 12 (the right end in the figure) and a drive unit attachment port 13 (the upper end in the figure) as three opening ends. Inside the bellows valve main body 10, a flow path through which the controlled fluid flows is formed between the flow path forming port 11 and the flow path forming port 12. A bellows valve seat 14 is provided at a position facing the part mounting port 13.

  The bonnet portion 20 has a substantially annular fixed plate portion 21 fixed to the drive portion attachment port 13 and a substantially cylindrical shape in which one end side (the left end side in the figure) is fixed to the inner peripheral surface of the fixed plate portion 21. A rod guide 22 and a substantially cylindrical support member 23 fixed to the inner peripheral surface on the other end side (right end side in the figure) of the rod guide 22 are provided. The rod guide 22 has an operating piston rod 60 inserted therein, and supports the operating piston rod 60 so as to be slidable in the axial direction. The support member 23 seals between the outer peripheral surface of the operating piston rod 60 and the inner peripheral surface of the rod guide 22 and supports the operating piston rod 60 so as to be slidable in the axial direction.

  The disc portion 30 is a substantially cylindrical disc stem ring 31 fixed to the tip end portion (left end portion in the figure) of the working piston rod 60, and a substantially fixed portion fixed to the tip end portion (left end in the figure) of the disc stem ring 31. A disk-shaped disk part main body 32 and a resin member 33 which is formed in a substantially disk shape with, for example, tetrafluoroethylene resin or the like and is provided on one end surface (left end surface in the figure) of the disk part main body 32 are provided. . Such a disk portion 30 moves forward and backward together with the operating piston rod 60 so as to be able to contact and separate from the bellows valve seat 14 inside the bellows valve body 10, and opens and closes the flow path in the bellows valve body 10.

  The bellows 40 is formed, for example, of a stainless cylindrical material in a bellows shape, and is provided to extend and contract in the axial direction between the disk portion 30 and the bonnet portion 20 in the bellows valve main body 10. The front end (left end in the figure) of the bellows 40 is fixed to the disc stem ring 31, and the base end (right end in the figure) is fixed to a substantially annular bellows flange 41. The bellows flange 41 is sandwiched between the drive portion attachment port 13 and the fixed plate portion 21 with one end side (left end side in the figure) of the rod guide 22 inserted through the center hole. With such a bellows 40, the inside of the bellows valve body 10 and the operating piston rod 60 side are completely cut off, and the controlled fluid can be prevented from flowing out from the inside of the bellows valve body 10 to the operating piston rod 60 side. In addition, it is possible to prevent impurities and lubricating oil from flowing into the bellows valve body 10 from the working piston rod 60 side.

The drive unit 50 includes a main cylinder 51 fixed to the outside of the bonnet unit 20 and an operating piston 52 slidably provided in the main cylinder 51. The main cylinder 51 has a substantially annular cylinder flange 511 in which the outer peripheral surface of the other end (right end in the figure) of the rod guide 22 is fixed to the center hole, and one axial end (left end in the figure) is fixed to the cylinder flange 511. And a substantially disc-shaped cylinder cover 513 fixed to the other axial end portion (right end in the figure) of the cylindrical portion 512. The working piston 52 is formed in a disk shape having a diameter substantially equal to the inner diameter of the cylindrical portion 512 and is slidable along the axial direction of the cylindrical portion 512.
The inside of the main cylinder 51 is partitioned into two cylinder chambers by an operating piston 52. The first cylinder chamber 514 is a space between the operating piston 52 and the cylinder cover 513, and the pressurized air is supplied to the first cylinder chamber 514 through a pressure fluid introduction passage 515 provided in the cylinder cover 513. Is to be supplied. The second cylinder chamber 516 is a space between the operating piston 52 and the cylinder flange 511, and pressurized air is supplied to the second cylinder chamber 516 via a pressure fluid introduction path 517 provided in the cylinder flange 511. It has come to be.

  The working piston rod 60 is formed in a solid round bar shape, and the disk portion 30 is fixed to the tip portion (left end in the figure) as described above. The intermediate portion of the operating piston rod 60 is disposed on the inner peripheral side of the bellows 40 and the rod guide 22 and is supported by the rod guide 22 and the support member 23 so as to be slidable in the axial direction. Further, the base end side (right end side in the figure) of the working piston rod 60 passes through the center hole of the cylinder flange 511 and is fixed to the working piston 52. As a result, the working piston rod 60 moves forward and backward in the axial direction together with the working piston 52, and the bellows valve seat 14 is opened and closed by the disc portion 30.

[Configuration of Operation Maintenance Mechanism 70]
Next, the operation maintaining mechanism 70 will be described.
The operation maintaining mechanism 70 is a valve mechanism that controls the opening / closing operation of the bellows valve seat 14 of the disc portion 30. As shown in FIG. 4, the first valve mechanism 80 (right in the figure) and the second valve mechanism 90 ( This is a combination of the two valve mechanisms (left in the figure). In the first valve mechanism 80 and the second valve mechanism 90, the first ports 816 and 916 are connected to the pressure fluid supply means via the connecting pipes 80A and 90A. The second port 817 of the first valve mechanism 80 is connected to the first cylinder chamber 514 via a connecting pipe 80B, and the second port 917 of the second valve mechanism 90 is connected to the second cylinder via the connecting pipe 90B. Connected to chamber 516. Further, the fourth port 819 of the first valve mechanism 80 is connected to the third port 918 of the second valve mechanism 90 via the connecting pipe 80C, and the fourth port 919 of the second valve mechanism 90 is connected via the connecting pipe 90C. It is connected to the third port 818 of the first valve mechanism 80.

  Although not shown, the pressurized fluid supply means includes a pressurized air supply unit, an atmosphere release unit, an electromagnetic valve connected to the pressurized air supply unit, the atmosphere release unit, the connection pipe 80A, and the connection pipe 90A. It is provided with a flow path switching means so that the flow path of the pressurized air can be switched to a predetermined state. That is, when the flow path of the pressurized air is switched to one state by the flow path switching means, the pressurized air from the pressurized air supply unit is supplied to the first cylinder chamber 514 via the connecting pipe 80A and the like. In addition, the pressurized air inside the second cylinder chamber 516 is circulated to the atmosphere release section via the connecting pipe 90A and the like, and is released to the atmosphere. When the flow path switching means is switched to the second state, the pressurized air from the pressurized air supply unit is supplied to the second cylinder chamber 516 via the connecting pipe 90A and the like, and the first cylinder Pressurized air inside the chamber 514 is circulated to the atmosphere release portion via the connecting pipe 80A and the like, and is released to the atmosphere.

The first valve mechanism 80 and the second valve mechanism 90 have the same structure. Hereinafter, the corresponding constituent elements will be described using reference numerals 80 and 800 in the first valve mechanism 80, and reference numerals 90 and 900 in the second valve mechanism 90.
First, a specific configuration of the first valve mechanism 80 will be described mainly based on FIGS. FIG. 5 is a side sectional view showing the operation maintaining mechanism, and FIG. 6 is a plan view thereof.
The first valve mechanism 80 includes a valve main body 81 formed in a substantially rectangular parallelepiped shape, and a valve body 82, a compression spring 83, a piston rod 84, and a piston 85 provided inside the valve main body 81.

  The valve main body 81 has a substantially rectangular parallelepiped main body 86 in which circular holes are respectively formed in both end surface portions in the longitudinal direction, and a substantially square first lid portion 87 fixed to the upper end surface portion of the main body 86 in FIG. And a substantially square second lid portion 88 fixed to the lower end surface portion of the main body portion 86 in FIG. A gasket 871 is provided between the main body portion 86 and the first lid portion 87, and a gasket 881 is provided between the main body portion 86 and the second lid portion 88 so that the inside of the valve main body 81 is sealed. Has been.

  In the valve body 81, a pressure fluid introduction chamber 811 positioned substantially at the center of the body portion 86, a pressure fluid discharge chamber 812 adjacent to the pressure fluid introduction chamber 811, the pressure fluid introduction chamber 811, and A valve seat 813 located between the pressure fluid discharge chambers 812 is provided.

  The pressure fluid introduction chamber 811 is a substantially cylindrical space whose axial direction is along the longitudinal direction of the main body portion 86, and is provided in communication with the first port 816 and the fourth port 819. The inner diameter dimension of the pressure fluid introduction chamber 811 is set larger than the diameter dimension of the piston rod 84, and the piston rod 84 is inserted therein. In the state in which the piston rod 84 is inserted, a gap is formed between the pressure fluid introduction chamber 811 and the piston rod 84, whereby the first port 816 and the fourth port 819 are connected via the pressure fluid introduction chamber 811. Communication is secured.

  The valve seat 813 is formed in a tapered shape whose diameter increases from the pressure fluid introduction chamber 811 toward the pressure fluid discharge chamber 812. A valve element 82 is detachably provided at a position facing the valve seat 813. The taper surface portion 821 of the valve body 82 abuts on the valve seat 813, so that the flow path of pressurized air between the pressure fluid introduction chamber 811 and the pressure fluid discharge chamber 812 is closed. An O-ring 822 is provided on the tapered surface portion 821 of the valve body 82 so that the flow path is more reliably closed.

The pressure fluid discharge chamber 812 is a substantially cylindrical space coaxial with the pressure fluid introduction chamber 811, and between the lower end side in FIG. Two ports 817 are provided in communication. The inner diameter dimension of the pressure fluid discharge chamber 812 is set to be larger than the diameter dimension of the valve body 82, and a space in which the valve body 82 moves is secured inside.
In addition, a compression spring 83 is accommodated in the pressure fluid discharge chamber 812, and this compression spring 83 is supported by a substantially cylindrical spring support portion 882 formed integrally on the inner surface of the second lid portion 88. ing. Thereby, the compression spring 83 biases the valve body 82 in the valve seat closing direction. The inner peripheral surface of the spring support portion 882 is a support hole 883 into which the base end portion of the piston rod 84 is inserted and supports the piston rod 84 slidably in the axial direction.

  When the pressurized air introduced into the pressure fluid introduction chamber 811 via the first port 816 acts on the valve body 82 by the valve body 82 and the compression spring 83 having the above-described configuration, the valve body 82 is a compression spring. The valve seat 813 is opened by moving in the valve opening direction (downward in FIG. 5) against the urging force of 83. When the pressurized air flows backward from the pressure fluid discharge chamber 812 to the pressure fluid introduction chamber 811, the valve body 82 moves in the valve closing direction (upward in FIG. 5) by the bias of the compression spring 83. Thus, the valve seat 813 is closed.

  A cylinder chamber 814 is located at a position opposite to the valve seat 813 across the pressure fluid introduction chamber 811 inside the main body 86, that is, between the upper end side of the main body 86 in FIG. 5 and the first lid 87. Is provided. Further, a connecting hole 815 is provided between the cylinder chamber 814 and the pressure fluid introduction chamber 811 inside the main body 86.

The cylinder chamber 814 is a substantially cylindrical space coaxial with the pressure fluid introduction chamber 811 and is provided in communication with the third port 818.
A piston 85 is slidably housed in the cylinder chamber 814, and good sliding performance is secured by a slide ring 851 provided on the outer peripheral surface of the piston 85. Further, an O-ring 852 is provided on the outer peripheral surface of the piston 85, and the cylinder chamber 814 is partitioned into two spaces by such a piston 85, and a sealed state between the spaces is ensured.

One space 814 </ b> A in the cylinder chamber 814, that is, a space between the first lid portion 87 and the piston 85 is supplied with pressurized air via a third port 818. And it is comprised so that the pressure fluid introduce | transduced from the 3rd port 818 may act on the upper end surface in FIG.
On the other hand, in the other space 814 </ b> B of the cylinder chamber 814, the tip end portion (upper end in FIG. 5) of the piston rod 84 extends through the pressure fluid introduction chamber 811 and the connection hole 815. It is coaxially connected to the lower end surface in FIG.
As a result, when the pressurized air introduced from the third port 818 acts on the piston 85, the piston 85 moves to the space 814B side and opens the valve seat 813 by the valve element 82 via the piston rod 84. It is like that.

The other space 814B of the cylinder chamber 814 communicates with the outside through an air hole 814C provided in the side surface portion of the main body 86, and air in the other space 814B can enter and exit. Thus, even when the piston 85 slides, the pressure in the other space 814B is made equal to the atmospheric pressure.
Further, the diameter of the piston 85 is formed larger than the diameter of the piston rod 84. For this reason, even when the pressure of the pressurized air introduced from the third port 818 is low, the piston 85 is surely slid to open the valve seat 813 by the valve element 82. That is, high responsiveness of the piston 85 is ensured.

  The connection hole 815 is a substantially cylindrical space coaxial with the pressure fluid introduction chamber 811, and the inner diameter dimension thereof is set to be substantially equal to the diameter dimension of the piston rod 84. The connecting hole 815 supports the piston rod 84 inserted therein so as to be slidable in the axial direction. Further, an O-ring 815C fixed by a washer 815A and a snap ring 815B is provided on the inner peripheral surface of the connection hole 815, and the cylinder chamber 814 and the pressure fluid introduction chamber 811 are sealed.

In FIG. 5, a first port 816 is formed in the center of the right side surface portion of the main body 86 in the drawing so as to communicate with the pressure fluid introduction chamber 811, and the male screw formed in the first port 816 includes A connecting pipe 80A (see FIG. 4) is connected.
In addition, a second port 817 is bored below the left side surface portion of the main body 86 in the drawing so as to communicate with the pressure fluid discharge chamber 812, and a female pipe formed in the second port 817 has a connecting pipe 80B. (See FIG. 4) are connected.
As a result, the pressurized air supplied from the pressure fluid supply means to the first port 816 via the connection pipe 80A is supplied to the pressure fluid introduction chamber 811, the pressure fluid discharge chamber 812, the second port 817, and the connection pipe 80B. And the pressure fluid introduction path 515 to be supplied to the first cylinder chamber 514.

  Further, as shown in FIG. 5, a third port 818 is formed in the center of the first lid portion 87 so as to communicate with the cylinder chamber 814, and a female pipe formed in the third port 818 is connected to a connecting pipe. 90C is connected. The connecting pipe 90C is also connected to the fourth port 919 in the second valve mechanism 90. For this reason, the pressurized air supplied from the second valve mechanism 90 via the connecting pipe 90 </ b> C and the third port 818 is introduced into one space 814 </ b> A of the cylinder chamber 814.

  Further, as shown in FIG. 6, a fourth port 819 is bored at the center of the lower side surface portion of the main body portion 86 in the drawing so as to communicate with the pressure fluid introduction chamber 811. A connecting pipe 80C is connected to the internal thread formed in the fourth port 819, and this connecting pipe 80C is also connected to the third port 918 in the second valve mechanism 90. As a result, the pressurized air supplied from the pressure fluid supply means to the first port 816 via the connection pipe 80A is supplied to the pressure fluid introduction chamber 811, the fourth port 819, the connection pipe 80C, and the second valve mechanism 90. The third port 918 is also introduced into the cylinder chamber 914 of the second valve mechanism 90.

Next, a specific configuration of the second valve mechanism 90 will be described mainly based on FIGS. As described above, the second valve mechanism 90 has the same configuration as that of the first valve mechanism 80, and therefore a specific description of each component will be omitted as appropriate.
The second valve mechanism 90 includes a main body 96, a first lid 97 and a second lid 98, a valve main body 91, a valve body 92, a compression spring 93, a piston rod 94, and a piston 95. It is configured with.
The valve body 91 includes a pressure fluid introduction chamber 911, a pressure fluid discharge chamber 912, a valve seat 913, a cylinder chamber 914, a connection hole 915, a first port 916, a second port 917, and a third port 918. And a fourth port 919. The cylinder chamber 914 is partitioned into two spaces 914A and 914B by a piston 95, and the space 914B communicates with an air hole 914C provided in the main body portion 96. The connection hole 915 includes a washer 915A, a snap ring 915B, and a ring 915C. The valve body 92 has a tapered surface portion 921 and an O-ring 922. The piston 95 includes a slide ring 951 and an O-ring 952. The first lid portion 97 includes a gasket 971, and the second lid portion 98 includes a gasket 981, a spring support portion 982, and a support hole 983.

[Bellows valve operation]
The operation of the bellows valve 1 configured as described above will be described with reference to the drawings.
First, the operation of closing the bellows valve seat of the bellows valve 1 during normal operation will be described mainly with reference to FIG.

As an initial state, the bellows valve seat 14 is opened by the disk portion 30, and the controlled fluid is flowing from the flow path forming port 11 toward the flow path forming port 12, as indicated by an arrow A in the figure. Illustrate. The controlled fluid may flow from the flow path forming port 12 toward the flow path forming port 11.
In order to close the bellows valve seat 14 with the disc part 30 from this initial state, the working piston 52 and the working piston rod 60 are moved to the left in the figure.

Specifically, as shown by an arrow B on the upper right in the figure, pressurized air is supplied from the pressurized air supply unit of the pressurized fluid supply means to the first port 816 in the first valve mechanism 80 via the connecting pipe 80A. Supply. As a result, the valve body 82 moves to the right in the drawing against the bias of the compression spring 83 by the action of the pressurized air introduced into the first port 816, and the valve seat 813 is opened by the valve body 82. . Therefore, the pressurized air flows to the second port 817 as indicated by an arrow C in the figure. At the same time, the pressurized air also flows to the fourth port 819 as indicated by the arrow D in the figure, and further passes through the connecting pipe 80C to the second valve mechanism 90 as indicated by the arrow E in the figure. Introduced into the three port 918.
The pressurized air supplied to the second port 817 flows to the first cylinder chamber 514 via the connecting pipe 80B and the pressure fluid introduction path 515 as indicated by an arrow F in the drawing. For this reason, the disk part 30 moves to the left side in the figure via the working piston 52 and the working piston rod 60 and is in a state of closing the bellows valve seat 14 as indicated by a two-dot chain line in the figure.

  During such movement of the disk portion 30, the second cylinder chamber 516 shrinks, and as shown by arrows G and H in the figure, the pressurized air inside the second cylinder chamber 516 is supplied to the pressure fluid introduction path 517 and It is introduced into the second port 917 of the second valve mechanism 90 through the connecting pipe 90B. Here, since the pressurized air is introduced into the third port 918 of the second valve mechanism 90 from the fourth port 819 of the first valve mechanism 80, the valve body 92 causes the valve seat 913 to be moved by the action of the piston 95. It is in an open state. Accordingly, the pressurized air flows to the first port 916 as shown by an arrow I in the figure, and is aired at the atmosphere opening portion of the pressurized fluid supply means via the connecting pipe 90A as shown by an arrow J in the figure. To be released.

Next, the operation of opening the bellows valve seat of the bellows valve 1 during normal operation will be described mainly with reference to FIG.
As an initial state, as shown by a two-dot chain line in FIG. 7, a state where the bellows valve seat 14 is closed by the disk portion 30 and the flow of the controlled fluid is regulated is illustrated.
In order to open the bellows valve seat 14 from the initial state in the disk portion 30, the operating piston 52 and the operating piston rod 60 are moved to the right in the drawing.

Specifically, as indicated by an arrow K in the figure, pressurized air is supplied from the pressurized air supply unit of the pressurized fluid supply means to the first port 916 in the second valve mechanism 90 via the connecting pipe 90A. As a result, the valve body 92 moves to the left in the figure against the bias of the compression spring 93 by the action of the pressurized air introduced into the first port 916, and the valve seat 92 opens the valve seat 913. . Accordingly, the pressurized air flows to the second port 917 as indicated by an arrow L in the figure. At the same time, the pressurized air also flows to the fourth port 919 as shown by an arrow M in the figure, and further passes through the connecting pipe 90C to the first valve mechanism 80 in the first valve mechanism 80 as shown by an arrow N in the figure. Introduced into three ports 818.
Then, the pressurized air supplied to the second port 917 flows into the second cylinder chamber 516 through the connecting pipe 90B and the pressure fluid introduction path 517 as indicated by an arrow O in the drawing. For this reason, the disc part 30 moves to the right side in the figure via the working piston 52 and the working piston rod 60, stops at the position indicated by the two-dot chain line in the figure, and opens the bellows valve seat 14 It becomes.

  During the movement of the disk portion 30, the first cylinder chamber 514 shrinks, and as shown by arrows P and Q in the figure, the pressurized air inside the first cylinder chamber 514 is transferred to the pressure fluid introduction path 515 and It is introduced into the second port 817 of the first valve mechanism 80 via the connecting pipe 80B. Here, since pressurized air is introduced into the third port 818 of the first valve mechanism 80 from the fourth port 919 of the second valve mechanism 90, the valve body 82 moves the valve seat 813 by the action of the piston 85. It is in an open state. Therefore, the pressurized air flows to the first port 816 as indicated by an arrow R in the figure, and is aired at the atmosphere opening portion of the pressurized fluid supply means via the connecting pipe 80A as indicated by the arrow S in the figure. To be released.

Next, the operation of the bellows valve 1 when the supply of pressurized air from the pressurized fluid supply means is urgently stopped under some conditions will be described mainly based on FIG.
As an initial state, as shown by a two-dot chain line in FIG. 7, a state where the bellows valve seat 14 is closed by the disk portion 30 and the flow of the controlled fluid is regulated is illustrated. Note that the initial state may be a state in which the controlled fluid is circulated by the bellows valve seat 14 being opened by the disk portion 30 as indicated by a two-dot chain line in FIG.
When the supply of pressurized air from the pressurized fluid supply means is urgently stopped under any condition from this initial state, the operating piston 52 and the operating piston rod 60 are held at the positions at the time of the emergency stop as shown in FIG. Thus, the closed state of the bellows valve seat 14 by the disk portion 30 is maintained.

  That is, in FIG. 9, when the supply of pressurized air to the first port 816 is stopped, the valve body 82 of the first valve mechanism 80 is urged leftward in the figure by the compression spring 83, and the valve seat 813 is closed. At the same time, the valve body 92 of the second valve mechanism 90 is also urged rightward in the drawing by the compression spring 93 to close the valve seat 913. As a result, both the first valve mechanism 80 and the second valve mechanism 90 are in the valve closed state, so that the flow of pressurized air is stopped in both the first cylinder chamber 514 and the second cylinder chamber 516. Therefore, the movement of the actuating piston 52 in the left direction in the figure is restricted by the second valve mechanism 90, and the movement in the right direction in the figure is restricted by the first valve mechanism 80. Therefore, even when the disk portion 30 receives a pushing force in the right direction in the figure by the controlled fluid from the flow path forming port 11, it does not displace from the state shown in FIG. The closed state is maintained.

  At the time of the emergency stop, the introduction of pressurized air from the fourth port 919 of the second valve mechanism 90 to the third port 818 of the first valve mechanism 80 is stopped, and at the same time, the fourth of the first valve mechanism 80 is stopped. The introduction of pressurized air from the port 819 to the third port 918 of the second valve mechanism 90 is also stopped. For this reason, since pressurized air does not act on the pistons 85 and 95, the valve bodies 82 and 92 move in the valve closing direction without resistance.

[Effect of the embodiment]
According to the above-described embodiment, the following effects can be achieved.

In the operation maintaining mechanism 70, when pressurized air is supplied to the first ports 816 and 916 from the pressure fluid supply means, the valve bodies 82 and 92 open the valve seats 813 and 913 simultaneously with the action of the pressurized air. The pistons 85 and 95 cause the valve bodies 82 and 92 to open the valve seats 813 and 913 under the action of pressurized air. For this reason, the disk portion 30 can be advanced and retracted via the operating piston 52 and the operating piston rod 60.
When the supply of pressurized air from the pressure fluid supply means to the first ports 816 and 916 is urgently stopped in some situation, the valve bodies 82 and 92 are moved by the urging of the compression springs 83 and 93 to The seats 813 and 913 are closed. Therefore, the backflow of the pressurized air from the pressure fluid discharge chamber 812 to the pressure fluid introduction chamber 811 is prevented, and the flow of the pressurized air in the first cylinder chamber 514 and the second cylinder chamber 516 is stopped. The part 30 stops at the position at the time of emergency stop, and the operation of the bellows valve 1 can be maintained in the state at the time of emergency stop. At this time, since the pistons 85 and 95 are not subjected to the action of the pressurized air, the valve bodies 82 and 92 can move in the valve closing direction without resistance. Therefore, sudden operation of the bellows valve 1 that is not intended by the user during the emergency stop can be prevented.

  Since the first valve mechanism 80 and the second valve mechanism 90 have the same structure, mass production can be achieved, and the operation maintaining mechanism 70 and the bellows valve 1 can be manufactured at low cost. For example, even if one of the first valve mechanism 80 and the second valve mechanism 90 is damaged, the operation maintaining mechanism 70 can be repaired by replacing only the damaged side, so that the repair cost can be kept low.

Since the piston rods 84 and 94, the valve bodies 82 and 92, and the pistons 85 and 95 are provided inside the valve bodies 81 and 91, the first valve mechanism 80 and the second valve mechanism 90 can be made compact. . Therefore, providing the first valve mechanism 80 and the second valve mechanism 90 in the bellows valve 1 can prevent the bellows valve 1 from becoming large.
In addition, pressure fluid introduction chambers 811, 911, pressure fluid discharge chambers 812 and 912, valve seats 813 and 913, cylinder chambers 814 and 914, connection holes 815 and 915, first port 816 , 916, second ports 817 and 917, third ports 818 and 918, fourth ports 819 and 919 and air holes 814C and 914C, so that the main body portions 86 and 96 can be easily formed. Can be manufactured. Therefore, the first valve mechanism 80 and the second valve mechanism 90 can be manufactured at low cost.
Since the body portions 86 and 96 are provided with air holes 814C and 914C communicating with the other spaces 814B and 914B of the cylinder chambers 814 and 914, the pistons 85 and 95 can be slid smoothly.

  Since the O-rings 815C and 915C are provided in the connection holes 815 and 915, the cylinder chambers 814 and 914 and the pressure fluid introduction chambers 811 and 911 can be sealed. For this reason, it is possible to prevent the pressurized air from entering the cylinder chambers 814 and 914 from the pressure fluid introducing chambers 811 and 911, and to prevent problems such as leakage of the pressurized air from the air holes 814C and 914C. Also, since the O-rings 815C and 915C can be mounted with a simple configuration of being fixed to the washers 815A and 915A and the snap rings 815B and 915B, the first valve mechanism 80 and the second valve mechanism 90 can be easily made at low cost. Can be manufactured.

  Since the O-rings 822 and 922 are provided in the tapered surface portions 821 and 921 of the valve bodies 82 and 92, the pressure fluid introduction chamber 811 is in a state where the tapered surface portions 821 and 921 are in contact with the valve seats 813 and 913. 911 and the pressure fluid discharge chambers 812 and 912 can be more reliably shut off. Therefore, the operation of the bellows valve 1 can be more reliably maintained.

  Since the O-rings 852 and 952 are provided on the outer peripheral surfaces of the pistons 85 and 95, the one space 814A and 914A and the other space 814B and 914B in the cylinder chamber 814 can be sealed. For this reason, it is possible to prevent the occurrence of problems such as the pressurized air introduced into the third ports 818 and 918 leaking out from the air holes 814C and 914C.

  Since the second lid portions 88 and 98 are provided with spring support portions 882 and 982, the compression springs 83 and 93 can be surely installed, and the compression is performed inside the valve bodies 81 and 91 in some circumstances. The springs 83 and 93 can be prevented from falling over. Further, since the inner peripheral surfaces of the spring support portions 882 and 982 in the second lid portions 88 and 98 are formed as support holes 883 and 983 that are slidably supported at the base end portions of the piston rods 84 and 94, the piston rod 84, 94 good sliding motions can be obtained.

[Modification of Embodiment]
It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.

  In the above-described embodiment, the bellows valve main body is a substantially Y-shaped tubular air-operated bellows valve 1 as an example of the pressure fluid device, but is not limited thereto. That is, for example, a hydraulically actuated bellows valve, a bellows valve having a substantially T-shaped tubular valve body, and the like are further included. Any pressure fluid device such as a cylinder can be targeted.

  In the said embodiment, although the operation | movement maintenance mechanism 70 was comprised combining the 1st valve mechanism 80 and the 2nd valve mechanism 90, and the structure provided with respect to one bellows valve 1 was illustrated, it is not restricted to this. That is, the valve mechanism of the present invention may be installed alone in a flow path connecting a pressure fluid supply source and a pressure fluid device, and further, a predetermined arrangement is provided in a pressure fluid circuit provided with a plurality of pressure fluid devices. It is good also as a structure which installs 3 or more.

  In the said embodiment, although the structure which uses all the 1st thru | or 4th ports in the valve mechanism of this invention was illustrated, the usage method of the valve mechanism of this invention is not restricted to this. In other words, a valve mechanism in which only the first to third ports function can be obtained if the fourth port is blocked with a blocking plug, and each of the third and fourth ports is blocked with a blocking plug. Then, a valve mechanism in which only the first and second ports function can be obtained. Therefore, the valve mechanism of the present invention can be installed at various positions on the pressure fluid circuit, and the flow of pressurized air can be controlled in various states.

It is the sectional side view which showed the conventional single acting Y-type bellows valve. It is the figure which showed typically the cross section in the axial orthogonal direction of the action | operation piston rod in the brake device of the conventional pneumatic cylinder, (A) shows a brake release state, (B) shows a brake state. It is the figure which showed typically the side cross section of the conventional pneumatic cylinder and the brake device provided in this, (A) shows a brake release state, (B) shows a brake state. It is the sectional side view which showed the bellows valve and operation | movement maintenance mechanism which concern on one Embodiment of this invention. It is the sectional side view which showed the operation | movement maintenance mechanism in the said embodiment. It is the top view which showed the operation | movement maintenance mechanism in the said embodiment. It is the sectional side view which showed typically the operation | movement which obstruct | occludes the bellows valve seat of the bellows valve in the said embodiment. It is the sectional side view which showed typically the operation | movement which open | releases the bellows valve seat of the bellows valve in the said embodiment. It is the sectional side view which showed typically the state of the bellows valve when supply of the pressurized air in the said embodiment stopped.

Explanation of symbols

1 ... Bellows valve (pressure fluid equipment)
10 ... Bellows valve body 11 ... Channel formation port (one open end)
12 ... Channel formation port (second open end)
13 ... Driver mounting port (third open end)
14 ... Bellows valve seat 20 ... Bonnet part 30 ... Disk part (driven part)
40 ... Bellows 51 ... Main cylinder 514 ... First cylinder chamber 516 ... Second cylinder chamber 52 ... Operating piston 60 ... Operating piston rod 70 ... Operation maintaining mechanism 80 ... First valve mechanism 90 ... Second valve mechanism 81, 91 ... Valve Body 811, 911 ... Pressure fluid introduction chamber 812, 912 ... Pressure fluid discharge chamber 813, 913 ... Valve seat 814, 914 ... Cylinder chamber 816, 916 ... First port 817, 917 ... Second port 818, 918 ... Third port 819, 919 ... fourth ports 82, 92 ... valve bodies 83, 93 ... compression springs (biasing means)
84, 94 ... piston rod 85, 95 ... piston

Claims (5)

A valve body having a pressure fluid introduction chamber, a pressure fluid discharge chamber, and a valve seat provided at a position where the pressure fluid introduction chamber and the pressure fluid discharge chamber communicate with each other;
A valve body disposed opposite to the valve seat of the valve body, and provided to be able to open and close the valve seat;
An urging means that is supported by the valve body and urges the valve body in a valve seat closing direction;
A first port that communicates with the pressure fluid introduction chamber of the valve body and introduces a pressure fluid from the outside;
A second port communicating with the pressure fluid discharge chamber of the valve body and discharging pressure fluid to the outside;
In the valve body, a cylinder chamber is provided at a position opposite to the valve seat across the pressure fluid introduction chamber, and the pressure fluid introduction chamber is sealed.
One end side is fixed to the valve body, the other end side extends through the pressure fluid introduction chamber to the cylinder chamber in a sealed state, and is supported by the valve body so as to be slidable in the axial direction. A piston rod;
A piston connected to the other end of the piston rod and slidably provided in the cylinder chamber;
A third port for introducing a pressure fluid into a chamber divided by the piston of the cylinder chamber and opposite to the side where the piston rod is inserted;
The valve body is configured to open the valve seat against the biasing means when the pressure fluid introduced from the first port acts on the valve body,
Furthermore, the piston is configured to open the valve body against the biasing means via the rod when a pressure fluid introduced from the third port acts on the piston. A valve mechanism characterized by. The valve mechanism according to claim 1, wherein
The pressure fluid introduction chamber is provided with a fourth port connectable to the outside. The two valve mechanisms according to claim 2 are prepared, and each of the two valve mechanisms is connected to the pressure fluid supply means, and each of the second ports is connected to the pressure port. It is connected to a pressure fluid device driven by a pressure fluid from a fluid supply means, and further, each of the fourth ports of one valve mechanism is connected to the third port of the other valve mechanism. The operation maintenance mechanism of pressure fluid equipment. In the operation maintenance mechanism of the pressure fluid apparatus according to claim 3,
The pressure fluid device includes a main cylinder, an operation piston slidably provided in the main cylinder, and an operation piston rod connected to the piston and driving a driven portion.
The operation of the pressure fluid device is characterized in that each of the cylinder chambers partitioned by the operating piston of the main cylinder is connected to the second port of a different valve mechanism of the two valve mechanisms. Maintenance mechanism. A bellows valve for controlling the flow of fluid,
Formed in a tubular shape with open ends on three sides, a flow path is formed inside which a fluid flows from one open end to the second open end, and is provided on the flow path so as to face the three open ends. A bellows valve body having a bellows valve seat,
A bonnet portion that closes the three open ends of the bellows valve body;
A disk portion provided to be capable of opening and closing the bellows valve seat inside the bellows valve body;
A bellows provided between the disk portion and the bonnet portion inside the bellows valve body;
A main cylinder fixed to the outside of the bonnet portion;
An operating piston slidably provided in the main cylinder;
A base end portion is connected to the operating piston, and a front end side is connected to the disk portion through the bellows and the bonnet portion, and an operating piston rod for driving the disk portion;
An operation maintaining mechanism for the pressure fluid device according to claim 3 attached to the main cylinder,
A bellows valve characterized in that the second ports of different valve mechanisms of the two valve mechanisms are respectively connected to the cylinder chambers partitioned by the operating piston of the main cylinder.

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