JP4943126B2 - Emergency shut-off actuator with test moving mechanism - Google Patents

Description

  The present invention relates to an emergency shut-off actuator that is provided in a flow path such as a gas supply line (process line) of a plant or the like, and shuts off the flow path in an emergency, and is operated particularly in a predetermined opening state. The present invention relates to an emergency shut-off actuator with a test moving mechanism for performing functional tests.

Conventionally, an emergency shut-off valve for shutting off a flow path in an emergency is provided in a gas supply line of a plant or the like. The emergency shut-off valve is a valve that rapidly closes the valve body in response to an abnormality in the supply line such as a fire or an electric or air signal rupture.
Since this emergency shut-off valve does not operate during normal operation and is often fixed in a fully opened state, the valve body tends to stick or foreign matter tends to be caught. For this reason, if the valve body is fixed or a foreign object is caught, the valve may malfunction in an emergency, and in this case, reliability is lowered.

  In order to prevent this state, a test called a partial stroke test (hereinafter referred to as PST) for checking the state of the emergency shut-off valve during operation is generally performed on the process line. The PST is a function test of the emergency shut-off valve by partially operating the valve so as not to affect the supply process during operation, and without closing the process line during operation. The operation test of the emergency shut-off valve is performed while controlling the opening of the valve from the fully open state to the intermediate opening so that it can be confirmed that it can be reliably operated.

  By the way, the process line safety standards are set by, for example, international safety standards, the high-pressure gas safety association, and the like, and in order to satisfy these standards, PST is usually performed regularly. As a result, the reliability of the emergency shut-off valve in the process line is increased, so that it can be reliably operated in an emergency.

  As an emergency shut-off valve for a process line capable of confirming the operation of such a valve, there is an emergency shut-off valve of Patent Document 1. This emergency shut-off valve is provided with an engaging part on the valve shaft side and a stopper member on the outside of the valve shaft side. By engaging this engaging part and the stopper member to restrict the rotation of the valve shaft, The valve opening is limited so as not to be less than a predetermined value, and the operation of the valve body can be confirmed after mechanically restricting the rotation of the valve body with a mechanical stopper.

  In addition, as an emergency shutoff valve with the PST function, a drive unit having a pneumatic spring return mechanism is combined with a solenoid valve or pneumatic valve to operate the valve while maintaining the process line open. What has been made possible to confirm the operation is being proposed. This emergency shut-off valve is provided with a compressed air supply / exhaust passage for fully closed and intermediate opening for the cylinder of the drive unit, and controls the solenoid valve etc. connected by the circuit from each supply / exhaust port into the cylinder The rotation of the valve is controlled by sending or exhausting compressed air. When the valve is set to an intermediate opening, compressed air is exhausted from the air supply / exhaust port for the intermediate opening so that the piston is operated to the air supply / exhaust port. The opening degree is determined by the position of the air opening / exhaust port for intermediate opening, and the piston is operated up to this position so that the valve becomes the intermediate opening.

  On the other hand, Patent Document 2 discloses a spring-type two-stage open / close actuator for emergency shut-off that can open and close a valve in a fully closed position, an intermediate position, and a fully open position. In this actuator, when a pressurized fluid is supplied from the fully closed state of the valve, the piston is moved while compressing the spring so that the intermediate opening and the fully opened state can be achieved. In the cylinder device, a main piston and an intermediate opening piston are provided, and pressure fluid is applied to each piston. When the valve is set to an intermediate opening, the pressure fluid is applied to the intermediate opening piston. The intermediate opening piston moves to a moving distance determined by an adjusting bolt for adjusting the moving distance, so that a predetermined intermediate opening is obtained.

  As described above, at the time of a function test such as PST, the function test is performed by operating the emergency shut-off valve from the full open to the intermediate opening while maintaining the open state of the flow path by the emergency shut-off valve. In order to reliably perform a function test such as PST, it is necessary to have a mechanism that allows the emergency shut-off valve to be repeatedly operated from a fully open position to a predetermined intermediate opening degree.

JP-A-2005-163962 Japanese Patent Laid-Open No. 7-269511

  However, the emergency shut-off valve disclosed in Patent Document 1 is operated to an intermediate opening so that the opening of the valve body during the valve operation does not become a predetermined value or less, and the operation is confirmed by stopping in this state. It's just a thing.

Further, the emergency shut-off valve described above is provided with an air supply / exhaust port in the middle of the piston stroke of the drive unit, and the intermediate opening is determined by the position of this air supply / exhaust port, so the piston stroke is fixed at a fixed position. PST could only be performed with a certain stroke. Further, since the air supply / exhaust port is provided in the middle of the stroke of the piston, the diameter of the air port is small, and there is a possibility that the air supply / exhaust port may be clogged with dust or lubricating grease and adversely affect the air supply / exhaust. Further, when the piston passes through the air supply / exhaust port, the sealing O-ring provided on the outer periphery of the piston may be damaged.
In addition, since this emergency shutoff valve has an intermediate opening by moving the piston to the position of the air supply / exhaust port, this piston may exceed the predetermined stroke due to inertial force when moving the piston. The stroke could not be fixed, and there was a possibility that PST could not be performed accurately.

  On the other hand, Patent Document 2 discloses an actuator for setting an intermediate opening in which a compressed fluid is supplied in a fully closed state to operate up to an intermediate opening, and the state of the intermediate opening is maintained and the flow rate can be controlled. It is. For this reason, the adjustment range of the mechanical stroke of the piston of this actuator is the range from the fully closed state (in the spring spring state) to the intermediate opening. However, the emergency shut-off valve with PST function has a structure that operates a predetermined stroke (rotation angle) from the fully open state to the intermediate opening as described above. It was impossible to apply it as an emergency shutoff valve.

Although the circuit for controlling the supply and exhaust of compressed air of this actuator in this Patent Document 2 can control the emergency electromagnetic valve or the like to adjust the flow rate flowing through the valve, or emergency shut off from the valve open state, It is not intended to be able to perform repeated operations from fully open to intermediate opening.
As a result, it is considered that this actuator is used for PST whose main purpose is to repeatedly operate in the operating range from fully open to a predetermined intermediate opening and confirm that the valve operates without any problem. Not.

  The present invention has been developed as a result of diligent research in view of the above circumstances, and the purpose of the present invention is to perform a functional test of the valve by partially operating the valve during operation of the process line. A spring return actuator with a highly durable partial operation inspection mechanism that can perform this function test with high accuracy to prevent malfunction of the valve and reliably shut off the flow path in an emergency etc. Is to provide.

In order to achieve the above object, an invention according to claim 1 is a first piston having a first cylinder chamber in a cylinder, and a second cylinder chamber having a second cylinder chamber at a predetermined gap position via the first piston and a connecting member. the second piston is provided, the second piston is engaged at a predetermined position in the opening adjusting member, the rotation conversion mechanism in the middle of the rod provided in the first piston is provided, setting the spring device to the distal end of the rod The compressed fluid is supplied to and exhausted from the compressed fluid supply source to the first and second cylinder chambers via the first and second solenoid valves, respectively, and the rod is moved to a predetermined opening of the rotation conversion mechanism in an operating state. causes tested movement, a emergency shutoff actuator to allow emergency shutdown in the event of an emergency, and the first and second cylinder chamber first, the compressed fluid circuit a circuit connecting the second solenoid valve, the compression fluid An air actuated valve is disposed in the path between the first cylinder chamber and the first solenoid valve, the first solenoid valve is a switching solenoid valve for test movement, and the air actuated valve is the second solenoid valve. This is an emergency shut-off actuator with a test moving mechanism that is linked to make this second solenoid valve a solenoid valve for operation instruction at the time of emergency shut-off.

  The invention according to claim 2 is the emergency shut-off actuator with a test moving mechanism in which the opening degree of the rotation converting mechanism when the rod is subjected to the test movement is set to a predetermined angle from the fully open position to the approximately 70 degree opening degree.

According to a third aspect of the present invention, a three-way lock-up valve is provided between the first and second cylinder chambers and the first and second electromagnetic valves, respectively, and the three-way lock-up valve is operated by a decrease in air pressure or the like And an emergency shut-off actuator with a test moving mechanism that allows compressed air to be exhausted from the first and second cylinder chambers in accordance with this operation.

According to a fourth aspect of the present invention, an air operated valve is provided between the first cylinder chamber and the first electromagnetic valve, a three-way lockup valve is provided between the second cylinder chamber and the second electromagnetic valve, and the air operated The valve and the three-way lock-up valve are interlocked, and the three-way lock-up valve is operated due to a decrease in air pressure. In conjunction with this operation, the air-operated valve is interlocked to exhaust the compressed air from the first and second cylinder chambers. This is an emergency shut-off actuator with a test moving mechanism.

The invention according to claim 5 is an emergency with a test moving mechanism in which a circuit connecting the first and second cylinder chambers and the first and second electromagnetic valves is a compressed fluid circuit, and a self-excited transmission circuit is attached to the compressed fluid circuit. This is a shut-off actuator.

According to the first aspect of the present invention, it is possible to reliably perform a function test such as PST by partially operating a valve during operation of the process line, and to adjust the opening when partially operating the function test. It is possible to provide a spring return type actuator provided with a partial operation inspection mechanism that can be performed stably and can be stably operated even during PST during the emergency. The actuator of the present invention can be provided at a low cost by reducing the number of solenoid valves in the circuit, or the circuit can be changed according to various specifications. For example, the valve can be closed by changing the circuit. It can also be used as a two-stage open / close actuator that can be held at an intermediate opening when operating from a state to an open state . Furthermore, during a function test or the like, the first solenoid valve can be switched so that the repeated operation of the valve can be accurately performed within a predetermined stroke. On the other hand, when emergency shut-off is necessary, only the second solenoid valve is used. Therefore, it is possible to provide an emergency shut-off actuator with a test moving mechanism that can accurately perform operations at the time of a function test and an emergency shut-off.

  According to the second aspect of the present invention, the opening degree of the valve by the rotation conversion mechanism can be set by a wide adjustment range, and a functional test is performed with an appropriate amount of opening degree according to this implementation, and an emergency shut-off is performed. It is possible to propose an emergency shut-off actuator with a test movement mechanism that can improve the operation reliability.

According to the third and fourth aspects of the invention, when the air pressure decreases, the emergency air can be reliably shut off by exhausting the compressed air from the first and second cylinder chambers even during the test operation. Can do .

According to the fifth aspect of the present invention, a compressed fluid circuit using a self-excited transmission circuit can be provided. By switching the self-excited transmission circuit, it can be operated from an intermediate opening to a full opening, and the switching is repeated. go to facilitate repeated opening and closing of the valve in a predetermined opening range can be achieved on a functional test of the PST and the like.

Hereinafter, embodiments and actions of an emergency shut-off actuator with a test moving mechanism according to the present invention will be described in detail with reference to the drawings.
1 to 3 show a first embodiment of an emergency cutoff actuator according to the present invention. In the figure, the actuator body 1 includes a cylinder device 10, a rotation conversion mechanism 30, and a spring device 40. The cylinder device 10 supplies and exhausts a compressed fluid therein to reciprocate a piston and a piston rod (rod) 11 connected to the piston, and the rotation conversion mechanism 30 performs a reciprocating motion of the rod 11 on the output shaft 31. The spring device 40 is converted into a rotational motion so that the rod 11 can be restored by the elastic force of the spring 41. In the actuator body 1, the cylinder device 10 is connected to one side of the rotation conversion mechanism 30 and the spring device 40 is connected to the other side so as to be integrated. Below, the cylinder apparatus 10, the rotation conversion mechanism 30, and the spring apparatus 40 are each demonstrated in detail. In the embodiment, the case where the rod 12 operates in the direction against the elastic force of the spring 41 is referred to as a forward operation, and the case where the rod 12 operates in the direction of the elastic force of the spring 41 is referred to as a reverse operation.

  In the cylinder device 10, a second piston having a second cylinder chamber 17 at a predetermined gap position via a first piston 12 having a first cylinder chamber 13 and a connecting member 14 comprising the first piston 12 and a pin. 16 is provided. Further, the rod 11 is attached to the first piston 12, a rotation conversion mechanism 30 is provided in the middle of the rod 11, and a spring device 40 is provided at the tip of the rod 11.

  The first piston 12 is fixed to the rod 11 with a nut 15, and is provided so as to slide in the first cylinder chamber 13 in accordance with the reciprocating operation of the rod 11. On the other hand, the second piston 16 is not fixed to the rod 11 but presses the first piston 12 via the connecting member 14 fixed to the first piston 12 (for example, by the number of three or more), and The rod 11 is provided so that it can be pressed. Thereby, the pressure fluid sent to the air supply / exhaust port through the electromagnetic valve from the compressed fluid supply source 50 including a regulator with a filter acts on the second piston 16, and the second piston 16 is connected to the second piston 16 via the connecting member 14. One piston 12 is pressed, and as a result, the rod 11 can move a stroke of a predetermined distance (not shown).

  The center of the second piston 16 is guided by a rod-shaped opening adjusting member 18 and is slidably provided in the second cylinder chamber 17. The opening adjustment member 18 is screwed into an adjustment bush 20 attached to the end cap 10 a of the cylinder device 10 via a nut 21. The position of the adjusting bush 20 can be adjusted by loosening the nut 21 and moving it forward and backward relative to the end cap 10a. That is, the adjustment bush 20 is a stopper device that adjusts the position of the rear end of the second piston 16 when the second piston 16 is operated backward. The adjustment bush 20 enables fine adjustment of the position of the second piston 16 in the fully closed state. Provided. As a result, the fully closed state of the disk (not shown) connected to the output shaft 31 can be finely adjusted, and by this fine adjustment, the actuator of the present invention is applied to all 90 ° opening / closing valves such as a ball valve and a butterfly valve. Can be done.

  The operation of the second piston 16 is stopped by coming into contact with the nut 19 of the opening adjustment member 18 attached to the adjustment bush 20 during the forward operation. The opening adjustment member 18 can adjust its position by loosening the nut 23 and moving it forward and backward. That is, the opening adjusting member 18 is engaged at a predetermined position when the second piston 16 moves forward, and is provided so that the moving distance of the second piston 16 can be adjusted.

  Due to the above structure, the actuator body 1 operates the second piston 16 by the supply of the pressure fluid from the compressed fluid supply source 50 to move the rod 11 by a predetermined distance. By supplying pressurized fluid to the air supply / exhaust port 13a through the valve and acting on the first piston 12, the rod 11 can be moved in the forward direction by the remaining stroke. Further, the pressure fluid acting on the first piston 12 is exhausted by switching the electromagnetic valve, and the rod 11 can be returned in the backward direction by the remaining stroke by the elastic force of the spring 41.

  Further, the supply of air from the compressed fluid supply source 50 to the solenoid valve is shut off, the connection to the supply / exhaust port 17a is opened, and the pressure fluid does not act on the second piston 16, and the supply / exhaust port 13a is opened. The pressure fluid acting on the first piston 12 is released, and the elastic force of the spring 41 allows the rod 11 to move in all directions in multiple directions.

The rotation conversion mechanism 30 includes a pin 32 fixed to the rod 11 and a scotch yoke 34 fixed to the output shaft 31. The rotation conversion mechanism 30 is configured such that the pin 32 is moved back and forth when the rod 11 is reciprocated. The scotch yoke 34 is rotated by pushing and the output shaft 31 is rotated by this rotation, and the discs of the ball valve and the butterfly valve can be rotated to the open or closed state. The rotation conversion mechanism 30 may be other than the mechanism using the pin 32 and the scotch yoke 34 as in the present embodiment. For example, another conversion mechanism such as a mechanism using a rack and pinion (not shown) or a gear mechanism may be used. May be.
The rotation conversion mechanism 30 is housed in a substantially cylindrical body 35, and a cover-like rod guide 36 that can cover the side of the body 35 on the cylinder device 10 side of the body 35, and a body on the spring device 40 side. A rod guide 37 that can cover the other side portions is provided. The cylinder device 10 is connected to the rod guide 36 by a bolt 22.

  The spring device 40 includes a spring case 42 formed in a pipe shape, a spring cover 43, and an adjusting screw 44, and is provided in a state in which the spring 41 is elastically formed. The spring cover 43 is attached to the end side of the spring case 42, and an adjustment screw 44 is attached to the spring cover 43. The tip end side of the rod 11 can abut on the end side of the adjusting screw 44, and the position of the rod 11 during the forward movement can be determined. The adjusting screw 44 can adjust its end position by loosening the nut 45 and screwing in or unscrewing the nut 45. That is, the adjusting screw 44 serves as a stopper device that adjusts the position of the distal end side of the forward movement of the rod 11.

  When the spring device 40 is configured, the spring retainer 46 is fixed in advance to the distal end side of the rod 11 with a nut 47, and the spring 41 is elastically moved between the spring retainer 46 and the spring cover 43, and the spring case 42. The spring cover 43 is temporarily attached to the rod guide 37 of the rotation conversion mechanism 30, and the rod guide 37 and the spring cover 43 are connected by a tie rod 48 to be integrated. Thereby, after integration of the spring device 40 and the rod guide 37 (rotation conversion mechanism 30), the rod 11 is elastically repelled by the spring 41 in the backward operation direction. Although not shown, a plurality of springs can be provided in the spring device 40. In this case, the resilience can be increased.

  Next, a circuit connected to the actuator body will be described. The actuator body 1 is connected with a compressed fluid supply source 50 and two electromagnetic valves, first and second electromagnetic valves 60 and 70. The first and second cylinder chambers 13 and 17 of the cylinder device 10 are connected to the first and second electromagnetic valves 60 and 70 to form a circuit, and this circuit is a compressed fluid circuit 51. In the compressed fluid circuit 51, an air operating valve 52 is disposed between the first cylinder chamber 13 and the first electromagnetic valve 60, and the first electromagnetic valve 60 is a switching electromagnetic valve for test movement. Are interlocked with the second electromagnetic valve 70, and the second electromagnetic valve 70 is used as an operation instruction electromagnetic valve at the time of emergency shut-off. Note that the speed controller 53 in the figure can control the air supply speed of the compressed fluid during operation. By attaching the speed controller 53, the air supply / exhaust ports 13a and 17a can be processed to be large, and an arbitrary air supply speed can be obtained. Can be adjusted. The attachment of the speed controller 53 is optional and can be omitted as shown in FIGS. The same applies to the following embodiments.

The emergency shut-off actuator according to the present invention supplies the compressed fluid to the second cylinder chamber 17 from the compressed fluid supply source 50 via the second electromagnetic valve 70 to open the valve, and in this state, the first cylinder chamber 13 Compressed fluid is supplied / exhausted from the compressed fluid supply source 50 via the first electromagnetic valve 60, and the rod 11 is moved to a predetermined opening degree of the rotation conversion mechanism 30 in an operating state (during operation of a gas supply line not shown). Thus, a function test such as PST can be performed at the predetermined opening.
Further, in the compressed fluid circuit 51, by providing the electromagnetic valves 60 and 70 for function test and the air operated valve 52 of the air operated switching type, the first and second in an emergency even during the function test. This is an emergency shut-off actuator with a test moving mechanism that allows exhaust shut-off by exhausting from the cylinder chambers 13 and 17 and stops operation.

  During operation, the opening degree of the rotation conversion mechanism 30 when the rod 11 is moved by the test is set so as to be a predetermined opening degree from the fully open state in FIG. 3 to the 70 degree opening in FIG. Thus, the function test can be performed by reciprocating repeatedly within the operating range of the intermediate opening from the fully opened position. For this reason, the actuator main body 1 in this embodiment lengthens the full length of the opening degree adjustment member 18 and the cylinder apparatus 10, and the opening degree adjustment range of the rotation conversion mechanism 30 is a wide range from a fully open state to a substantially 70 degree opening degree. I am trying to take it. The adjustment of the opening can be performed by moving the opening adjusting member 18 back and forth with respect to the adjusting bush 20 and can be adjusted to an arbitrary angle from the fully open state to the approximately 70 ° opening.

Next, the operation of the emergency shut-off actuator in FIG. 1 in the compressed fluid circuit will be described. FIG. 1 shows a state in which the compressed fluid circuit 51 of the emergency shut-off actuator of the present invention is turned off and the disc is in the fully closed position.
In this case, since both the first and second electromagnetic valves 60 and 70 are demagnetized (off), the pressure fluid from the compressed fluid supply source 50 is blocked by the first and second electromagnetic valves 60 and 70. The air supply / exhaust ports 13a and 17a are both opened by the first and second electromagnetic valves 60 and 70, and the pressure fluid does not act on any of the first and second pistons 12 and 16. For this reason, the rod 11 connected to the first piston 12 is in the reverse operation state by the elastic force of the spring 41, and the disc is in the fully closed state.

  In FIG. 2, when the first electromagnetic valve 60 is demagnetized (maintaining demagnetization) and the second electromagnetic valve 70 is energized (ON), the compressed fluid is supplied only to the second cylinder chamber 17 and the second piston 16 is compressed. Move in the direction pushed by the fluid. In this case, the 2nd piston 16 presses the 1st piston 12 by pushing the connection member 14 with the movement. The second piston 16 moves until it comes into contact with the nut 19 of the opening adjustment member 18, and when the second piston 16 is stopped by the nut 19, the first piston 12 is also stopped at the same time. By this operation, the rod 11 moves a predetermined distance, the movement of the rod 11 is converted into the rotation of the output shaft 31 by the rotation conversion mechanism 30, the output shaft 31 rotates in the counterclockwise direction in the figure, and the disc has an intermediate opening degree. Stop with the valve open. The opening degree of the rotation conversion mechanism 30 (disk) at this time is a preset angle from a fully open position to a substantially 70 degree opening degree. Further, the spring 41 of the spring device 40 is compressed by the forward movement of the rod 11.

  Next, when the first electromagnetic valve 60 is excited in FIG. 3 while maintaining the supply state of the compressed fluid to the second cylinder chamber 17 (while the excitation of the second electromagnetic valve 70 is maintained), the compressed fluid is Is supplied to the first cylinder chamber 13 from the air supply / exhaust port 13a, and the first piston 12 is pushed by the compressed fluid and moves. The rod 11 is operated by the movement of the first piston 12, and the operation of the rod 11 is converted by the rotation conversion mechanism 30, and the output shaft 31 is further rotated counterclockwise to operate the disc to the fully open state.

  When performing a function test (for example, PST), the excitation / demagnetization of the first solenoid valve 60 is switched in this state. When the first electromagnetic valve 60 is switched to the demagnetization side, the compressed fluid in the first cylinder chamber 13 is exhausted from the first electromagnetic valve 60 via the air operation valve 52. When the compressed fluid is exhausted from the first cylinder chamber 13, the first piston 12 moves in the direction opposite to that when the compressed fluid is supplied by the elastic force of the spring 41, and the tip of the connecting member 14 of the first piston 12. Comes into contact with the second piston 16. At this time, since the supply of the compressed fluid is continued in the second cylinder chamber 17 and maintained in the moved state, the first piston 12 stops at this position. As the first piston 12 moves, the rod 11 moves, and as shown in FIG. 2, the output shaft 31 of the actuator rotates clockwise through the rotation conversion mechanism 30, and the disc operates to a predetermined intermediate opening degree. To do.

  Subsequently, when the first electromagnetic valve 60 is switched to the excitation side, the compressed fluid is supplied again to the first cylinder chamber 13 via the air operating valve 52, and the rotation conversion mechanism 30 returns to the state shown in FIG. By repeatedly demagnetizing and exciting the first electromagnetic valve 60, the supply and exhaust of the compressed fluid to the first cylinder chamber 13 is switched while the operating state of the actuator is maintained, so that the rotation conversion mechanism 30 is fully opened. The function test can be performed by repeatedly performing the test movement at a predetermined opening degree of approximately 70 °. Note that the supply of the compressed fluid to the first cylinder chamber 13 is controlled by the speed controller 53, whereby the operation speed during the function test can be adjusted, and a wide range of function tests can be performed.

  When the emergency shut-off is performed during the operation of the actuator described above, when the second electromagnetic valve 70 is demagnetized as shown in FIG. 1, the compressed fluid is exhausted from the second cylinder chamber 17, and at this time, the second electromagnetic valve 70 and the circuit The compressed fluid in the first cylinder chamber 13 is also exhausted from the connected air operation valve 52. In this way, the air operating valve 52 exhausts the compressed air in the first cylinder chamber 13 in conjunction with the second electromagnetic valve 70, so that the second electromagnetic valve 70 is an operation instruction electromagnetic valve at the time of emergency shut-off. Thus, the compressed fluid can be simultaneously exhausted from both the first and second cylinder chambers 13 and 17 in one step.

When the compressed fluid is exhausted from the first and second cylinder chambers 13 and 17, the first piston 12 operates in the reverse direction opposite to that when the compressed fluid is supplied due to the elastic force of the spring 41. The second piston 16 is pressed via 14, and the two pistons 12, 16 return to the state shown in FIG. 1.
When the first piston 12 is actuated, the rod 11 is also actuated in accordance with this actuating, and the actuating of the rod 11 is converted into a rotating action by the rotation converting mechanism 30, and the output shaft 31 is rotated in the closing direction. By this operation, the disc can be rapidly operated to the closed state by the elastic force of the spring 41, and it is possible to cope with an emergency operation.

The emergency shut-off actuator with a test moving mechanism of the present invention has the circuit configuration as described above, and it is possible to perform a function test such as PST by exciting and demagnetizing only the first electromagnetic valve 60. Since only the operation of is required, the probability of failure is reduced.
Moreover, since the 2nd solenoid valve 70 and the air action valve 52 are utilized in order to fix to an intermediate opening degree, it is almost unnecessary to act | operate except at the time of emergency interruption | blocking.
As a result of the above, it is possible to configure a minimum number of air devices, such as solenoid valves, in the actuator circuit, and to operate a minimum number of air devices both during function tests and during emergency shutdown. Therefore, the probability of failure can be reduced. For this reason, for example, the probability of failure that is strictly regulated by the safety level (SIL) of the High Pressure Gas Safety Association can be reduced.

  Further, the angle of the rotation conversion mechanism 30 during the test movement can be adjusted to an arbitrary angle from the fully open to the 70 ° opening by the opening adjustment member 18, and this angle is adjusted by the mechanical stopper function of the opening adjustment member 18. Therefore, the opening degree during the function test can be set accurately, and when the disc is opened and closed, the stroke of the rod 11 does not change due to the influence of the inertia force of the disc. Therefore, it is possible to prevent the disk from overrunning the operating range and changing the flow rate of the valve.

  When the first and second pistons 12 and 16 are operated, the pistons 12 and 16 do not pass through the air supply / exhaust ports 13a and 17a, so that a large diameter can be provided, and dust and grease for lubrication are clogged. Therefore, smooth air supply / exhaust operation can be maintained. Further, since the O-rings 12a and 16a mounted on the outer peripheral sides of the pistons 12 and 16 do not pass through the air supply / exhaust ports 13a and 17a, the O-rings 12a and 16a are not damaged.

  4 and 5 show a second embodiment of the emergency cutoff actuator of the present invention. In the figure, the actuator main body 1 is the same as that of the first embodiment, and the description thereof is omitted. Also, with respect to the circuit, the same parts as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof is omitted. The same applies to the following embodiments.

  In the actuator according to the second embodiment, a circuit connecting the first and second cylinder chambers 13 and 17 of the actuator body 1 and the first and second electromagnetic valves 60 and 70 is a compressed fluid circuit 55, and the first electromagnetic valve 60 is The switching electromagnetic valve for test movement, the emergency cutoff valve, and the second electromagnetic valve 70 are made to function as an intermediate opening fixing and emergency cutoff valve.

The compressed fluid circuit 55 in this embodiment is a circuit using two electromagnetic valves as described above, and is operated by controlling the circuit in sequence.
Although not shown, when both the first and second solenoid valves 60 and 70 are demagnetized and the compressed fluid circuit 55 is turned off, the rod 11 of the actuator body 1 is elastically springed by the spring 41 as in the above embodiment. , And the disc is fully closed.

  In FIG. 4, when the first electromagnetic valve 60 is demagnetized and the second electromagnetic valve 70 is excited, the compressed fluid is supplied only to the second cylinder chamber 17, and the second piston 16 moves in the direction pushed by the compressed fluid. Similarly to the above, the second piston 16 pushes the connecting member 14 to push the first piston 12 in the same direction. The second piston 16 moves until it contacts the nut 19 of the opening adjustment member 18, and the second piston 16 and the first piston 12 are stopped by the nut 19. As a result, the rod 11 moves a predetermined distance, and the movement of the rod 11 is converted by the rotation conversion mechanism 30 so that the disc has an intermediate opening. The opening degree of the rotation conversion mechanism 30 (disk) at the intermediate opening degree is set to an arbitrary angle from the fully open position to the approximately 70 degree opening degree. At this time, the spring 41 is compressed by the movement of the rod 11.

  Next, when the first electromagnetic valve 60 is excited in FIG. 5 while maintaining the supply state of the compressed fluid to the second cylinder chamber 17, the compressed fluid is also supplied into the first cylinder chamber 13, and the first piston. The rod 11 is actuated by the operation of the first piston 12, the output shaft 31 is rotated by the conversion of the rotation converting mechanism 30, and the disc is fully opened.

  At the time of a function test such as PST, it can be performed by switching excitation / demagnetization of the first solenoid valve 60 from this state. When the first electromagnetic valve 60 is switched to the demagnetizing side, the compressed fluid in the first cylinder chamber 13 is exhausted from the first electromagnetic valve 60. The exhaust causes the first piston 12 to move in the reverse operation direction opposite to that when the compressed fluid is supplied due to the elastic force of the spring 41, as shown in FIG. 4, and the tip of the connecting member 14 comes into contact with the second piston 16. The first piston 12 stops at this position. The rod 11 is moved by the movement of the first piston 12, and the output shaft 31 is rotated clockwise through the rotation conversion mechanism 30 by the movement of the rod 11, so that the disc is operated to a predetermined intermediate opening.

  Subsequently, when the first electromagnetic valve 60 is switched to the excitation side, the compressed fluid is supplied to the first cylinder chamber 13 and returns to the state shown in FIG. By repeatedly demagnetizing and exciting the first electromagnetic valve 60, the test movement at a predetermined opening from the fully open state of the rotation conversion mechanism 30 to about 70 ° is repeatedly performed while maintaining the operating state of the actuator. Functional tests can be performed.

When the emergency shutoff is performed during the operation of the actuator, although not shown, the signal to the first and second electromagnetic valves 60 and 70 is demagnetized. When the first and second electromagnetic valves 60 and 70 are demagnetized, the compressed fluid is exhausted from the first and second cylinder chambers 13 and 17. The spring 41 is repelled by the exhaust of the compressed fluid, and the first piston 12 operates in the reverse operation direction opposite to that when the compressed fluid is supplied. Simultaneously with this operation, the second piston 16 is pushed through the connecting member 14. The first and second pistons 12 and 16 operate in the backward direction.
When the first piston 12 is actuated, the rod 11 is also actuated in accordance with this actuating, and the actuating of the rod 11 is converted into a rotating action by the rotation converting mechanism 30, and the output shaft 31 is rotated in the closing direction.

  6 to 8 show a third embodiment of the emergency cutoff actuator of the present invention. In the figure, this actuator is provided with three-way lock-up valves 57 and 58 between the first and second cylinder chambers 13 and 17 and the first and second electromagnetic valves 60 and 70 in the compressed fluid circuit 56, respectively. Is. When this circuit causes a drop in air pressure or the like in the compressed fluid circuit 56, the three-way lock-up valves 57 and 58 are operated, and the compressed air is supplied from the first and second cylinder chambers 13 and 17 along with this operation. The emergency shutoff can be performed by exhausting the air.

  FIG. 6 shows a state in which the three-way lock-up valves 57 and 58 are operated and exhausted, and the actuator body 1 is provided in a shut-off state by this exhaust. FIG. 7 shows a state in which the first electromagnetic valve 60 is demagnetized and the second electromagnetic valve 70 is excited, and the rotation conversion mechanism 30 is operated to an intermediate opening degree as in the above embodiment. Further, FIG. 8 shows a state where both the first and second electromagnetic valves 60 and 70 are excited and the rotation conversion mechanism 30 is fully opened. By repeating the excitation and demagnetization of the first electromagnetic valve 60 from the intermediate opening state shown in FIG. 7, the test movement of the rotation conversion mechanism 30 can be performed, and thereby the function test of the actuator can be performed.

  Further, when an emergency shut-off is performed during operation of the actuator, the first and second cylinder chambers 13 are demagnetized by demagnetizing the first and second electromagnetic valves 60 and 70 as in the case of the second embodiment. 17, the compressed fluid is exhausted, and the output shaft 31 is rotated in the closing direction in accordance with the return operation of the pistons 12 and 16 by the elastic force of the spring 41, so that the disc can be rotated in the closed state.

9 to 11 show a fourth embodiment of the emergency cutoff actuator of the present invention. In this embodiment, an air operated valve 52 is provided between the first cylinder chamber 13 and the first electromagnetic valve 60, and a three-way lockup valve 57 is provided between the second cylinder chamber 17 and the second electromagnetic valve 70. The air actuated valve 52 and the three-way lockup valve 57 can be interlocked. As a result, when the air pressure in the air pipe decreases due to stoppage of the compressor (not shown), damage to the pipe, etc., and the specified pressure is reached, the three-way lockup valve 57 is operated. The operation valve 52 is interlocked so that compressed air is exhausted from the first and second cylinder chambers 13 and 17 to perform an emergency shut-off. The designated pressure (set pressure) is preferably about 3 kg / cm ² because the spring force of a general spring return actuator is 4 kg / cm ² .

FIG. 9 shows a circuit state at the time of emergency shutoff of the actuator. FIG. 10 shows a state where the first electromagnetic valve 60 is demagnetized and the second electromagnetic valve 70 is excited to operate the rotation conversion mechanism 30 to the intermediate opening. In FIG. FIG. 2 shows a state where both the second electromagnetic valves 60 and 70 are excited to fully open the rotation conversion mechanism 30.
Note that the operations of the actuator body 1 and the first and second electromagnetic valves 60 and 70 during the intermediate opening (functional test) and fully open (emergency shut-off) function in the same manner as in the above-described embodiment, and thus are omitted.

  12 to 15 show a fifth embodiment of the emergency shut-off actuator of the present invention. In this embodiment, a circuit connecting the first and second cylinder chambers 13 and 17 and the first and second electromagnetic valves 60 and 70 is a compressed fluid circuit 71, and a self-excited transmission circuit 72 is attached to the compressed fluid circuit 71. It is a thing.

In the compressed fluid circuit 71, a first air operated valve 74 and a second air operated valve 75 interlocking with the second electromagnetic valve 70 are disposed between the first cylinder chamber 13 and the compressed fluid supply source 50. ing.
Further, an intermediate limit valve 76 and a fully open limit valve 77 are disposed between the first solenoid valve 60 as the test moving switching solenoid valve and the first air operation valve 74. Thus, a self-excited transmission circuit 72 from the compressed fluid supply source 50 to the first electromagnetic valve 60, the intermediate limit valve 76, the fully open limit valve 77, and the first air operation valve 74 is configured.
The limit valves 76 and 77 operate so that the air flow path can be switched when a roller (not shown) of the limit valve is pushed by a cam (not shown) fixed to the output shaft 31.

In FIG. 12, when the second electromagnetic valve 70 is excited in the demagnetized state of the first electromagnetic valve 60 and pressure fluid is supplied to the second cylinder chamber 17, the second piston 16 and the first piston 12 move to rotate the rotation conversion mechanism. 30 operates to an intermediate opening. At this time, the second air operating valve 75 is in an air supply state, but since the first air operation valve 74 is in an exhaust state, the first cylinder chamber 13 is not supplied with air and the intermediate opening degree is increased. Is maintained.
The first electromagnetic valve 60 that turns on and off the self-excited transmission circuit 72 is in a demagnetized state.

  Next, while maintaining the supply state of the compressed fluid to the second cylinder chamber 17, the first electromagnetic valve 60 is excited as shown in FIG. 13, and the compressed air is operated by the first air via the intermediate limit valve 76. Supply to valve 74. As a result, the first air operating valve 74 is switched to enter an air supply state, and compressed air is supplied to the first cylinder chamber 13 via the first and second air operating valves 74 and 75. And the 1st piston 12 moves and operates rotation conversion mechanism 30 to a full open state.

  When the rotation conversion mechanism 30 is operated from the intermediate opening to the fully open state, the intermediate limit valve 76 is switched so as to close the circuit with the first electromagnetic valve 60 and communicate with the fully open limit valve 77. Then, when the rotation changing mechanism 30 is fully opened, the fully open limit valve 77 is switched to the exhaust state as shown in FIG. As a result, the first air operating valve 74 is switched to an exhaust state, and the compressed air is discharged from the first cylinder chamber 13 through the first and second air operating valves 74 and 75. And the 1st piston 12 moves to the direction opposite to the time of compression fluid supply by the elastic force of spring 41, and operates rotation conversion mechanism 30 to an intermediate opening.

When the rotation conversion mechanism 30 is operated from the fully open state to the intermediate opening, the fully open limit valve 77 is switched to close the opening with the intermediate limit valve 76. When the rotation conversion mechanism 30 is in the intermediate opening state, the intermediate limit valve 76 is switched to communicate with the first electromagnetic valve 60 by disconnecting the full-open limit valve 77 as shown in FIG. As a result, the first air operating valve 74 is switched to enter an air supply state, and compressed air is supplied to the first cylinder chamber 13 via the first and second air operating valves 74 and 75. Thereby, the 1st piston 12 moves and operates rotation conversion mechanism 30 to a full open state.
As described above, the rotation conversion mechanism 30 can automatically reciprocate between the fully opened state and the intermediate opening without operating the first and second electromagnetic valves 60 and 70.

As shown in FIG. 15, when the second electromagnetic valve 70 is demagnetized, compressed air is exhausted from the second cylinder chamber 17, and the second air operating valve 75 is switched in conjunction with the second electromagnetic valve 70. The compressed air in the one cylinder chamber 13 is also exhausted. As a result, the spring 41 is repelled and the output shaft 31 is rotated in the closing direction as in the above embodiment.
In FIG. 15, the first solenoid valve 60 that turns on and off the self-excited transmission circuit 72 is in a demagnetized state, but the emergency shut-off operation can be performed even in an excited state.

  The emergency shut-off actuator with a test movement mechanism of the present invention can be provided in a circuit configuration other than the above embodiment, and can be provided in various circuit configurations by combining with an actuator body having a spring return device.

1 is a circuit diagram showing a first embodiment of an emergency cutoff actuator with a test moving mechanism in the present invention. FIG. It is the circuit diagram which showed the intermediate opening state of the rotation conversion mechanism in FIG. It is the circuit diagram which showed the fully open state of the rotation conversion mechanism in FIG. It is the circuit diagram which showed 2nd Embodiment of the actuator for emergency cutoff with a test movement mechanism in this invention. It is the circuit diagram which showed the fully open state of the rotation conversion mechanism in FIG. It is the circuit diagram which showed 3rd Embodiment of the actuator for emergency cutoff with a test movement mechanism in this invention. It is the circuit diagram which showed the intermediate opening state of the rotation conversion mechanism in FIG. It is the circuit diagram which showed the fully open state of the rotation conversion mechanism in FIG. It is the circuit diagram which showed 4th Embodiment of the actuator for emergency cutoff with a test movement mechanism in this invention. FIG. 10 is a circuit diagram showing an intermediate opening state of the rotation conversion mechanism in FIG. 9. FIG. 10 is a circuit diagram showing a fully opened state of the rotation conversion mechanism in FIG. 9. It is the circuit diagram which showed 5th Embodiment of the actuator for emergency cutoff with a test movement mechanism in this invention. It is a circuit diagram which shows the state which excited the 1st solenoid valve in FIG. It is the circuit diagram which showed the full open state of the rotation conversion mechanism in FIG. It is the circuit diagram which showed the fully closed state of the rotation conversion mechanism in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Actuator main body 10 Cylinder apparatus 11 Rod 12 1st piston 13 1st cylinder chamber 14 Connecting member 16 2nd piston 17 2nd cylinder chamber 18 Opening adjustment member 30 Rotation conversion mechanism 40 Spring apparatus 50 Compressed fluid supply source 51 Compressed fluid circuit 52 Air Actuated Valves 57, 58 3-way Lock-up Valve 60 First Electromagnetic Valve 70 Second Electromagnetic Valve 72 Self-Excited Transmission Circuit

Claims (5)

A first piston having a first cylinder chamber is provided in the cylinder, and a second piston having a second cylinder chamber is provided at a predetermined gap position via the first piston and a connecting member. engaged at a predetermined position, the middle provided the rotation conversion mechanism of the rod which is provided in the first piston, set only a spring device on the tip of the rod, said first and second cylinder chamber, a compressed fluid supply source first more respectively, the compressed fluid through a second solenoid valve by supply and exhaust, the rod causes tested moved to a predetermined opening degree of the rotation conversion mechanism in the operating state, emergency that allow emergency shutdown in the event of an emergency A shut-off actuator , wherein a circuit connecting the first and second cylinder chambers and the first and second solenoid valves is a compressed fluid circuit, and the compressed fluid circuit includes the first cylinder chamber and the first solenoid valve. Between An air actuated valve is provided, the first solenoid valve is used as a test moving switching solenoid valve, the air actuated valve is interlocked with the second solenoid valve, and the second solenoid valve is operated as an electromagnetic for instructing operation during emergency shut-off. An emergency shut-off actuator with a test moving mechanism characterized by being a valve .   2. The emergency shut-off actuator with a test moving mechanism according to claim 1, wherein an opening degree of the rotation conversion mechanism when the rod is subjected to the test movement is set to a predetermined angle from a fully open position to a substantially 70 ° opening degree. A three-way lock-up valve is provided between the first and second cylinder chambers and the first and second solenoid valves, respectively, and the three-way lock-up valve is operated due to a decrease in air pressure. It said first test movement mechanism with an emergency shut-off actuator of claim 1, to allow exhaust of compressed air from the second cylinder chamber. An air operated valve is provided between the first cylinder chamber and the first electromagnetic valve, a three-way lockup valve is provided between the second cylinder chamber and the second electromagnetic valve, and the air operated valve and the three-way lock are provided. An up valve is interlocked, the three-way lock-up valve is operated due to a decrease in air pressure, and the compressed air is exhausted from the first and second cylinder chambers by interlocking with the operation of the air operated valve. The emergency shut-off actuator with a test movement mechanism according to 1 . 2. The emergency shutoff with a test moving mechanism according to claim 1 , wherein a circuit connecting the first and second cylinder chambers and the first and second electromagnetic valves is a compressed fluid circuit, and a self-excited transmission circuit is attached to the compressed fluid circuit. Actuator.

Images