Pressure Control Device

Abstract

No explosion-proof structure is required, allowing for greater design freedom, and the rotation angle can be adjusted with relatively high precision while allowing for operation with simple controls. [Solution] The rotation angle setting mechanism K includes a second ratchet gear G2 that can rotate the pressure adjustment screw in a second rotation direction X2a that is opposite to the first rotation direction X1a, and a second engagement claw EF2 that enters an engaged state in which it engages with the second ratchet gear G2 when it moves forward in the second direction along the second direction X2, causing the second ratchet gear G2 to rotate in the second rotation direction X2a, and enters a disengaged state in which it does not engage with the second ratchet gear G2 when it moves backward in the second direction along the second direction X2.

Description

[Technical Field]

[0001] The present invention relates to a pressure control device comprising a pressure control valve that controls the secondary pressure of a fluid flow path through which a fluid flows to a set pressure, and a pressure setting unit that changes and sets the set pressure, wherein the pressure setting unit has a pressure setting spring that can change and set the set pressure by adjusting the spring load, a rotation angle setting mechanism that can set the rotation angle of a pressure adjustment screw that can adjust the spring load, and a control unit that controls the rotation angle setting mechanism. [Background technology]

[0002] When controlling the set pressure of a pressure regulator, as described in Patent Document 1, a common method is to control the rotation of the pressure adjusting screw of the pressure regulator with an electric motor (for example, a servo motor, a stepping motor, an AC motor, or a brushless DC motor). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-107971 Summary of the Invention [Problem to be solved by the invention]

[0004] The technology disclosed in Patent Document 1 uses an electric motor, so it requires an explosion-proof structure in environments where flammable gas (for example, fuel gas such as city gas 13A) may be floating, making the design difficult. Designing and adopting a dedicated explosion-proof motor from scratch is often not profitable as a final product, so a more realistic approach is to use a commercially available explosion-proof motor. However, when using an explosion-proof electric motor, there is a limited lineup of commercially available motors, so there are many cases where the specifications (torque, rotation speed, power consumption, size, cost, etc.) do not match the design. Even if a commercially available explosion-proof motor that matches the specifications is found, there is still a risk that the product will be discontinued. On the other hand, if a non-explosion-proof commercially available electric motor is used, measures such as enclosing it in a pressure-resistant explosion-proof case are required, and special technology and know-how are required for explosion-proof design, which requires special certification.

[0005] If an air motor is used as the motor, there is no need to make the drive section explosion-proof. However, because it is more difficult to accurately control the rotation angle of an air motor than with an electric motor, feedback control using the rotation angle signal of the pressure adjustment screw, etc., is required, which complicates the control design.

[0006] The present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide a pressure control device that does not require an explosion-proof structure, allows for improved design freedom, and allows operation with simple control while being able to adjust the rotation angle with relatively high precision. [Means for solving the problem]

[0007] The pressure control device for achieving the above object comprises: a pressure control valve that controls a secondary pressure of a fluid flow path through which the fluid flows to a set pressure; a pressure setting unit that changes and sets the set pressure, The pressure setting unit is a pressure control device including a pressure setting spring that can freely change and set the set pressure by adjusting the spring load, a rotation angle setting mechanism that can set the rotation angle of a pressure adjustment screw that can freely adjust the spring load, and a control unit that controls the rotation angle setting mechanism, and its characteristic configuration is as follows: The rotation angle setting mechanism includes: a first ratchet gear that can rotate the pressure adjusting screw in a first rotation direction; a first engagement pawl that, when moving forward in a first direction along the first direction, is in an engaged state in which it engages with the first ratchet gear, causing the first ratchet gear to rotate in the first rotational direction, and that, when moving backward in the first direction along the first direction, is in a disengaged state in which it does not engage with the first ratchet gear; a second ratchet gear that can rotate the pressure adjusting screw in a second rotation direction that is opposite to the first rotation direction; a second engagement pawl that, when moving forward in the second direction along the second direction, is brought into an engaged state in which it engages with the second ratchet gear, causing the second ratchet gear to rotate in the second rotational direction, and that, when moving backward in the second direction along the second direction, is brought into a disengaged state in which it does not engage with the second ratchet gear; a first gas cylinder that is capable of projecting and sending the first engagement claw forward in the first direction and retracting and pulling the first engagement claw back in the first direction; and a second gas cylinder that is capable of projecting and sending the second engagement claw forward in the second direction and retracting and pulling the second engagement claw back in the second direction. The device is characterized in that it is equipped with a gas flow adjustment unit that adjusts the pressure supply of gas to the first gas cylinder when the device moves forward and the discharge of gas from the first gas cylinder when the device moves backward, and that adjusts the pressure supply of gas to the second gas cylinder when the device moves forward and the discharge of gas from the second gas cylinder when the device moves backward.

[0008] According to the above characteristic configuration, the rotation angle setting mechanism does not use an electric motor (e.g., servo motor, stepping motor, AC motor, brushless DC motor) that requires explosion-proofing. Therefore, in the design, there is no need to use special technology or know-how associated with explosion-proof design that requires special certification, making the design easier than before. Furthermore, even if the fluid to be controlled by the pressure control device in the rotation angle setting mechanism is a fluid that requires explosion protection, such as city gas, the ratchet gear and the gas cylinder that drives the ratchet gear do not need to be explosion-proof, so they can be installed near the pressure control valve without requiring an explosion-proof structure, thereby improving the flexibility of installation.

[0009] Furthermore, with the above rotation angle setting mechanism, the pressure adjusting screw is rotated by a predetermined rotation angle with a simple configuration in which the pawl engages with the ratchet gear and moves in the first or second direction, so the rotation angle can be set with relatively high precision. This eliminates the need to acquire rotation angle information of the pressure adjusting screw and perform feedback control based on the acquired information, as is the case when an air motor is used, and enables highly accurate setting of the rotation angle with simple control.

[0010] As a result, it is possible to realize a pressure control device that does not require an explosion-proof structure, thereby improving design freedom, and that can be operated with simple control while still being able to adjust the rotation angle with relatively high precision.

[0011] Further characteristic features of the pressure control device include: As the gas flow adjusting unit, a first gas flow path that pressurizes the gas to the first gas cylinder so as to move the first engagement claw forward in the first direction, and a first electromagnetic valve that can open and close the first gas flow path; a second gas flow path that pressurizes the gas to the second gas cylinder so as to move the second engagement claw forward in the second direction, and a second electromagnetic valve that can open and close the second gas flow path; the control unit controls the first solenoid valve to be in an open state when the first engagement claw is moved forward in the first direction, In addition, when the second engagement claw is moved forward in the second direction, the second electromagnetic valve is controlled to be in an open state.

[0012] When a gas cylinder is used to drive a ratchet gear as in the above configuration, a solenoid valve must be used to control the pressure supply of gas to the gas cylinder. If the fluid to be controlled is a flammable gas (for example, a fuel gas such as city gas 13A), when the solenoid valve is placed near the pressure control valve, it is necessary to use a relatively expensive solenoid valve with an explosion-proof structure.

[0013] According to the above characteristic configuration, for example, by configuring the gas cylinder into which gas has been pressurized to return (discharge the pressurized gas) by the biasing force of a spring or the like, it is possible to effectively configure the system with two solenoid valves, a first solenoid valve and a second solenoid valve.If a configuration is adopted in which the first solenoid valve and the second solenoid valve are located near the pressure control valve, the number of expensive explosion-proof solenoid valves can be reduced, providing economic benefits.

[0014] Further characteristic features of the pressure control device include: The first solenoid valve and the second solenoid valve have an explosion-proof structure.

[0015] With this configuration, the first solenoid valve and the second solenoid valve can be installed near the pressure control valve, and the pressure control device can be made compact.

[0016] Further characteristic features of the pressure control device include: The rotation angle setting mechanism has a rotation resistance portion on the rotation shaft of the pressure adjusting screw that resists rotation of the pressure adjusting screw in the first rotation direction or the second rotation direction.

[0017] According to the rotation angle setting mechanism described above, the engaging pawl engages with the ratchet gear, causing the ratchet gear to rotate and thereby rotate the pressure adjustment screw. Therefore, depending on the speed at which the engaging pawl moves, it is conceivable that the rotation angle of the ratchet gear may become larger than necessary. According to the above characteristic configuration, the rotation resistance portion provides resistance against rotation of the pressure adjustment screw in the first rotation direction or the second rotation direction, so even if the movement speed of the engagement pawl is relatively high, the ratchet gear and the pressure adjustment screw can be preferably prevented from rotating after the engagement pawl and the ratchet gear change from an engaged state to a disengaged state, and the rotation angle of the pressure adjustment screw can be adjusted relatively accurately while appropriately matching the movement amount of the engagement pawl (movement amount forward in the first direction or forward in the second direction) and the rotation angle of the ratchet gear (rotation angle in the first rotation direction or the second rotation direction).

[0018] Further characteristic features of the pressure control device include: the rotation angle setting mechanism is provided between the first ratchet gear and the pressure adjusting screw, and between the second ratchet gear and the pressure adjusting screw, without interposing a clutch therebetween; The pressure adjusting screw is provided with a rotation operating part that can be manually rotated in the first rotation direction and the second rotation direction.

[0019] As explained above, according to the present invention, when the first engagement claw is disengaged from the first ratchet gear and the second engagement claw is disengaged from the second ratchet gear, the pressure adjustment screw can rotate freely. Therefore, even with a simple configuration that does not include a clutch, the administrator can set the rotation angle of the pressure adjustment screw by manually rotating the rotation operating part, thereby improving the operability of setting the rotation angle.

[0020] Further characteristic features of the pressure control device include: The gas supply system is configured so that air compressed by a compressor can be pressure-fed to the first gas cylinder and the second gas cylinder.

[0021] According to the above characteristic configuration, the first gas cylinder and the second gas cylinder can be driven using air that is not flammable, and therefore the device can be operated relatively safely.

[0022] Further characteristic features of the pressure control device include: The fuel gas, which is the fluid to be controlled to the set pressure, is configured so that the fuel gas on the primary side of the pressure control valve can be pressurized as the gas to the first gas cylinder and the second gas cylinder.

[0023] According to the above characteristic configuration, the first gas cylinder and the second gas cylinder can be driven using the pressure of the fuel gas to be controlled, which is reduced from the primary pressure to the secondary pressure, as a power source. Therefore, there is no need to prepare separately pressurized air, etc., and therefore the configuration of a compressor, etc. for compressing air, etc. can be omitted, which simplifies the configuration and reduces the power required to drive compressors, etc., thereby improving energy efficiency.

[0024] Further characteristic features of the pressure control device include: a temporary storage tank capable of storing the fuel gas as the gas discharged from the first gas cylinder and the second gas cylinder after being pressure-fed to the first gas cylinder and the second gas cylinder; a discharge flow path connecting the temporary storage tank and a secondary side of the fluid flow path; a discharge flow path opening / closing valve that opens and closes the discharge flow path; a secondary pressure measuring unit capable of measuring the pressure on the secondary side of the pressure control valve, When the pressure measured by the secondary pressure measuring unit is less than a predetermined dischargeable threshold, the control unit changes the discharge flow path opening / closing valve from a closed state to an open state, and executes discharge control to discharge the fuel gas stored in the temporary storage tank to the secondary side of the fluid flow path.

[0025] According to the above characteristic configuration, the fuel gas used to drive the first gas cylinder and the second gas cylinder can be guided to the secondary side of the fluid flow path without being dispersed into the atmosphere, and used for combustion on the secondary side.This improves safety compared to when the gas is dispersed into the atmosphere, and makes it possible to realize a device with less energy loss. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a schematic configuration diagram of a pressure control device according to an embodiment. [Figure 2] FIG. 2 is a schematic configuration diagram of a rotation angle setting mechanism of the pressure control device according to the embodiment. [Figure 3] FIG. 10 is a schematic configuration diagram of a pressure control device according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0027] The pressure control device 100 according to the embodiment of the present invention does not require an explosion-proof structure, allowing for improved design freedom, and is capable of adjusting the rotation angle with relatively high precision while enabling operation with simple control. A pressure control device 100 according to an embodiment will be described below with reference to FIGS.

[0028] 1, the pressure control device 100 includes a pressure control valve Vc that adjusts the secondary pressure of a fluid flow path 1 to a set pressure, and a pressure setting unit that changes and sets the set pressure, the pressure setting unit comprising a pressure setting spring 2 that can change and set the set pressure by adjusting the spring load, a rotation angle setting mechanism K that can set the rotation angle of a pressure adjustment screw 3 that can adjust the spring load, and a control device S (an example of a control unit) that controls the rotation angle setting mechanism K. In this embodiment, the fluid flowing through the fluid flow path 1 is a fuel gas (e.g., city gas 13A) whose main component is methane. Incidentally, in the pressure control device 100 according to this embodiment, from the viewpoint of explosion prevention, all components other than the control device S are set inside a building BK3 having an explosion-proof structure.

[0029] Furthermore, this pressure control device 100 is provided with a pilot valve Vp that supplies drive pressure to the pressure control valve Vc so that the secondary pressure becomes the set pressure, and the pressure setting unit is configured to change and set the set pressure by controlling the operation of this pilot valve Vp.

[0030] The pressure control valve Vc is provided in the fluid flow path 1, and the pilot valve Vp is provided in a branching and merging flow path 5 that branches off from a point upstream of the installation location of the pressure control valve Vc in the fluid flow path 1 and joins at a point downstream of the installation location of the pressure control valve Vc in the fluid flow path 1. Although not shown in the drawings, for example, the fluid flow path 1 is configured to branch into a plurality of branch paths downstream of the pressure control valve Vc, and each of the plurality of branch paths is connected to each consumer, thereby supplying a fluid such as natural gas to a plurality of consumers. The pressure control valve Vc is configured to adjust the secondary pressure downstream to a set pressure that is lower than the primary pressure upstream.

[0031] As shown in Fig. 1, the pressure control valve Vc is configured so that a valve element 8 is moved by a diaphragm 7 to open and close the valve element 8. The diaphragm 7 is biased by a pressure adjustment spring 9 made of a compression coil spring so as to move the valve element 8 to the opening side. A throttle 10 is provided in the upstream flow path section 5u upstream of the installation location of the pilot valve Vp in the branch and junction flow path 5, and a driving pressure supply path 11 branches off from the section downstream of the installation location of the throttle 10 in the upstream flow path section 5u. The driving pressure supply passage 11 is connected to a driving pressure introduction chamber 12 that faces the surface of the diaphragm 7 opposite to the surface pressed by the pressure adjustment spring 9, among the chambers defined by the diaphragm 7.

[0032] The pilot valve Vp has the same configuration as the pressure control valve Vc, and is configured so that a pilot valve element 14 is moved by a pilot diaphragm 13 to open and close the pilot valve element 14. The pilot diaphragm 13 is biased by a pressure setting spring 2 made of a compression coil spring so as to move the pilot valve element 14 to the opening side. Of the chambers partitioned by the pilot diaphragm 13, the secondary pressure introduction chamber 15 faces the side of the pilot diaphragm 13 opposite to the side pressed by the pressure setting spring 2. The downstream flow path portion 5d downstream of the installation location of the pilot valve Vp in the branch and junction flow path 5 is connected to the secondary pressure introduction chamber 15, and secondary pressure is introduced into the secondary pressure introduction chamber 15.

[0033] When the secondary pressure adjusted by the pressure control valve Vc is higher than the set pressure, the pressure in the secondary pressure introducing chamber 15 in the pilot valve Vp is high, and this pressure causes the pilot valve element 14 to move to the closing side against the biasing force of the pressure setting spring 2. As a result, the pressure in the driving pressure introducing chamber 12 of the pressure control valve Vc becomes the high primary pressure upstream of the pressure control valve Vc in the fluid flow path 1, and the valve element 8 moves to the closing side against the biasing force of the pressure adjustment spring 9, causing the secondary pressure to drop and be adjusted to the set pressure. Conversely, when the secondary pressure adjusted by the pressure control valve Vc is lower than the set pressure, the pilot valve element 14 moves toward the opening side due to the biasing force of the pressure setting spring 2. As a result, the flow rate of fluid in the branching and merging passage 5 is restricted by the restrictor 10, so the fluid in the driving pressure introducing chamber 12 flows toward the pilot valve Vp. Therefore, the pressure in the driving pressure introducing chamber 12 decreases, and the biasing force of the pressure adjusting spring 9 moves the valve element 8 toward the opening side, causing the secondary pressure to rise and be adjusted to the set pressure.

[0034] The set pressure of the pressure control valve Vc is not always kept constant, but is adjusted to a target set pressure that changes depending on the load. For example, in the fluid flow path 1, the load is high during times when high demand is expected, so the set pressure is adjusted to a high target set pressure, and during other times when the load is low, so the set pressure is adjusted to a low target set pressure.

[0035] As shown in FIG. 1, the pressure adjustment screw 3, which is rotated by a rotation angle setting mechanism K described later, is threaded into a spring bearing 16 that abuts the end of the pressure setting spring 2 opposite the side that abuts against the pilot diaphragm 13, and by adjusting the rotation angle of the pressure adjustment screw 3 with the rotation angle setting mechanism K, the spring bearing 16 is moved along the axial direction of the pressure adjustment screw 3 (the direction along arrow Y in FIG. 2), thereby adjusting the compression amount of the pressure setting spring 2 and adjusting the spring load of the pressure setting spring 2. In other words, the pilot valve Vp is configured to change and set the set pressure in a manner that changes the secondary pressure when the pilot valve element 14 opens and closes by adjusting the rotation angle of the pressure adjusting screw 3 with the rotation angle setting mechanism K to adjust the compression amount of the pressure setting spring 2. For example, the set pressure can be changed and set to a higher pressure as the rotation angle of the pressure adjusting screw 3 is increased in the direction in which the pressure setting spring 2 is compressed.

[0036] As shown in FIGS. 1 and 2, the rotation angle setting mechanism K comprises a mechanical drive unit K1 that rotates the pressure adjusting screw 3 of the pilot valve Vp, and a gas flow adjusting unit K2 that transmits driving force to the mechanical drive unit K1.

[0037] As shown in FIG. 2, the mechanical drive unit K1 includes a first ratchet gear G1 that can rotate the pressure adjusting screw 3 in a first rotation direction X1a, a first engagement pawl NL1 that is in an engaged state where it engages with the first ratchet gear G1 when it moves forward in a first direction (toward the arrow X1) along the first direction X1, thereby rotating the first ratchet gear G1 in the first rotation direction X1a, and is in a disengaged state where it does not engage with the first ratchet gear G1 when it moves backward in the first direction X1 (toward the base end of the arrow X1) along the first direction X1, a second ratchet gear G2 that can rotate the pressure adjusting screw 3 in a second rotation direction X2a that is the opposite rotation direction to the first rotation direction X1a, and a second engagement pawl NL1 that is in a disengaged state where it does not engage with the first ratchet gear G1 when it moves backward in the first direction X1 (toward the base end of the arrow X1) along the first direction X1, The first engaging claw NL1 is provided with a second engaging claw NL2 which, when moving forward in the first direction (toward the arrow X2), is in an engaged state in which it engages with the second ratchet gear G2, causing the second ratchet gear G2 to rotate in the second rotation direction X2a, and which, when moving backward in the second direction along the second direction X2 (toward the base end of the arrow X2), is in a disengaged state in which it does not engage with the second ratchet gear G2; a first gas cylinder AS1 which is capable of extending to send the first engaging claw NL1 forward in the first direction and of retracting to pull it back backward in the first direction; and a second gas cylinder AS2 which is capable of extending to send the second engaging claw NL2 forward in the second direction and of retracting to pull it back backward in the second direction. In this embodiment, the first ratchet gear G1 and the second ratchet gear G2 are provided in a form that rotates together with the pressure adjusting screw 3. To further explain, the first ratchet gear G1 is fitted and fixed to the pressure adjusting screw 3 by the first key groove RT1, and the second ratchet gear G2 is fitted and fixed to the pressure adjusting screw 3 by the second key groove RT2. Furthermore, the first ratchet gear G1 and the second ratchet gear G2 are provided at positions that are offset from each other in the axial direction (the direction of arrow Y in FIG. 2) along the rotation axis of the pressure adjusting screw 3.

[0038] The first engagement pawl NL1 is pivotally supported by a first bolt B1 on the cylinder shaft tip end SJ1a of the first cylinder shaft S31 of the first gas cylinder AS1 so as to be swingable along a first swing direction that is perpendicular to both the first direction X1 and the rotation axis (the direction along the arrow Y in FIG. 2) of the pressure adjusting screw 3. The first engagement pawl NL1 is biased by a first biasing member EF1 toward the first ratchet gear G1 in the first swing direction. Here, by adjusting the first engagement pawl NL1 so that when it moves in the first direction (the side indicated by the arrow X1), it goes from disengaged to engaged with the first ratchet gear G1, rotates the first ratchet gear G1 by a predetermined rotation angle, and then goes back to the disengaged state, it is possible to rotate the first ratchet gear G1 by the same rotation angle regardless of the amount of forward movement of the first engagement pawl NL1 in the first direction. This eliminates the need for detailed control of the flow rate of gas pumped into the first gas cylinder AS1.

[0039] The second engagement pawl NL2 is pivotally supported by a second bolt B2 on the cylinder shaft tip end SJ2a of the second cylinder shaft S32 of the second gas cylinder AS2 so as to be swingable along a second swing direction that is perpendicular to both the second direction X2 and the rotation axis (the direction along the arrow Y in FIG. 2) of the pressure adjusting screw 3. The second engagement pawl NL2 is biased by a second biasing member EF2 toward the second ratchet gear G2 in the second swing direction. Here, by adjusting the second engagement pawl NL2 so that when it moves in the second direction (the side indicated by the arrow X2), it goes from disengaged to engaged with the second ratchet gear G2, rotates the second ratchet gear G2 by a predetermined rotation angle, and then goes back to the disengaged state, the second ratchet gear G2 can be rotated by the same rotation angle regardless of the amount of forward movement of the second engagement pawl NL2 in the second direction. This eliminates the need for detailed control of the flow rate of gas pumped to the second gas cylinder AS2.

[0040] Incidentally, since the first engagement pawl NL1 is biased toward the first ratchet gear G1 by the first biasing member EF1, when the first engagement pawl NL1 moves rearward in the first direction, the first engagement pawl NL1 moves while contacting the first ratchet gear G1 (the same applies to the second engagement pawl NL2). In this case, the following configuration is provided to prevent the pressure adjusting screw 3 from rotating. That is, a rotation resistance portion RH that resists rotation of the pressure adjusting screw 3 in the first rotation direction X1a or the second rotation direction X2a is provided on the rotation axis of the pressure adjusting screw 3 as the rotation angle setting mechanism K. Specifically, the rotation resistance portion RH can be made of a rubber-like elastic member interposed between the pressure adjusting screw 3 and the housing KT of the pilot valve Vp.

[0041] Furthermore, the pressure control device 100 of this embodiment is provided with a rotation angle setting mechanism K, which includes a rotation operation unit RR that is arranged between the first ratchet gear G1 and the pressure adjustment screw 3 and between the second ratchet gear G2 and the pressure adjustment screw 3 without any clutch interposed therebetween and that can manually rotate the pressure adjustment screw 3 in the first rotation direction X1a or the second rotation direction X2a. In other words, in the pressure control device 100 according to this embodiment, the first ratchet gear G1 and the first engagement claw NL1, and the second ratchet gear G2 and the second engagement claw NL2 are in a disengaged state except while the rotation angle is being set by the rotation angle setting mechanism K, so that the rotation angle can be manually controlled by operating the rotation operating unit RR without operating the clutch, thereby realizing a pressure control device 100 that is easy to operate.

[0042] As shown in Figures 1 and 2, the gas flow adjustment unit K2 is configured to adjust the pressure of gas fed to the first gas cylinder AS1 during protruding movement and the discharge of gas from the first gas cylinder AS1 during retracting movement, as well as the pressure of gas fed to the second gas cylinder AS2 during protruding movement and the discharge of gas from the second gas cylinder AS2 during retracting movement. In this embodiment, the gas is compressed by the compressor Cp (e.g., air at a pressure of 0.1 MPa or more and 0.15 MPa or less) and can be pressure-fed to the first gas cylinder AS1 and the second gas cylinder AS2. The pressure of the air compressed by the compressor Cp is adjusted appropriately depending on the cylinder capacity, etc. In addition, the first gas cylinder AS1 has a biasing spring (not shown) that biases the first cylinder shaft S31, which has been pushed out by the gas, in the direction of retracting it, and the second gas cylinder AS2 has a biasing spring (not shown) that biases the second cylinder shaft S32, which has been pushed out by the gas, in the direction of retracting it.

[0043] 1 or 2, the gas flow adjuster K2 includes a first gas flow path L1 that pumps gas to the first gas cylinder AS1 to move the first engagement claw NL1 forward in the first direction (the side indicated by the arrow X1), a first solenoid valve VE1 that can open and close the first gas flow path L1, a second gas flow path L2 that pumps gas to the second gas cylinder AS2 to move the second engagement claw NL2 forward in the second direction (the side indicated by the arrow X2), and a second solenoid valve VE2 that can open and close the second gas flow path L2. The gas flow adjuster K2 also includes a third gas flow path L3 that can discharge the gas pumped to the first gas cylinder AS1 to the outside, a first throttle A1 that provides flow resistance for the third gas flow path L3, a fourth gas flow path L4 that can discharge the gas pumped to the second gas cylinder AS2 to the outside, and a second throttle A2 that provides flow resistance for the fourth gas flow path L4.

[0044] The control device S controls the first solenoid valve VE1 to an open state when the first engagement claw NL1 is moved forward in the first direction, and to a closed state when the first engagement claw NL1 is moved backward in the first direction (towards the base end of the arrow X2), and controls the second solenoid valve VE2 to an open state when the second engagement claw NL2 is moved forward in the second direction, and to a closed state when the second engagement claw NL2 is moved backward in the second direction (towards the base end of the arrow X2). In this embodiment, the first solenoid valve VE1 has a first explosion-proof structure BK1 made up of an explosion-proof case or the like, and the second solenoid valve VE2 also has a second explosion-proof structure BK2 made up of an explosion-proof case or the like.

[0045] The pressure control device 100 is equipped with a secondary pressure sensor P that measures the pressure on the secondary side of the pressure control valve Vc of the fluid flow path 1, and the control device S stores the rotation angle of the pressure adjustment screw 3 when the pilot valve body 14 transitions from a closed state to an open state when the secondary side measured by the secondary pressure sensor P is a predetermined reference value (set pressure reference value) as the reference rotation angle. Furthermore, when the control device S increases the set pressure from the set pressure reference value, it moves the first engagement pawl NL1 forward in the first direction (toward the arrow X1) and rotates the first ratchet gear G1 in the first rotation direction (direction along the arrow X1a) by a predetermined rotation angle (for example, 12° per tooth of the first ratchet gear G1).On the other hand, when the control device S decreases the set pressure from the set pressure reference value, it moves the second engagement pawl NL2 forward in the second direction (toward the arrow X2) and rotates the second ratchet gear G2 in the second rotation direction (direction along the arrow X2a) by a predetermined rotation angle (for example, 12° per tooth of the second ratchet gear G2). The control device S can set the set pressure to a desired value by pre-storing the amount of change in the set pressure that occurs when the first engagement claw NL1 is moved forward once in the first direction (or when the second engagement claw NL2 is moved forward once in the second direction).

[0046] [Another embodiment] (1) In the above embodiment, the rotation angle setting mechanism K is configured to set the rotation angle of the pressure adjusting screw 3 of the pilot valve Vp. Alternatively, the rotation angle setting mechanism K may be configured to set the rotation angle of the pressure adjusting screw 3 of a direct acting governor.

[0047] (2) In the above embodiment, the gas pressurized and delivered to the first gas cylinder AS1 is discharged to the outside via the first throttle A1 provided in the third gas flow path L3 connected to the first gas cylinder AS1. Alternatively, the first throttle A1 may be replaced with a third solenoid valve (not shown) whose opening and closing can be controlled by the control device S. In this case, the control device S may control the third solenoid valve to be closed when gas is being pressurized and to be open when gas is not being pressurized and delivered to the first gas cylinder AS1. In addition, the configuration example has been shown in which the gas pressurized into the second gas cylinder AS2 is discharged to the outside via the second throttle A2 provided in the fourth gas flow path L4 connected to the second gas cylinder AS2. As an alternative configuration, a fourth solenoid valve (not shown) that can be opened and closed by the control device S may be used instead of the second throttle A2. In this case, the control device S may control the fourth solenoid valve to be closed when gas is being pressurized into the second gas cylinder AS2 and to be open when gas is not being pressurized into the second gas cylinder AS2.

[0048] (3) In the above embodiment, the first solenoid valve VE1 and the second solenoid valve VE2 may be non-explosion-proof valves. In this case, the first gas flow path L1 and the second gas flow path L2 may be extended to the outside of the explosion-proof building BK3, the first solenoid valve VE1 and the second solenoid valve VE2 may be installed outside the building BK3, and the first gas flow path L1 downstream of the first solenoid valve VE1 and the second gas flow path L2 downstream of the second solenoid valve VE2 may be returned to the inside of the building BK3.

[0049] (4) In the above embodiment, the first ratchet gear G1 and the second ratchet gear G2 are configured to rotate together with the pressure adjusting screw 3. Alternatively, the first ratchet gear G1 and the second ratchet gear G2 may rotate the pressure adjusting screw 3 via an auxiliary gear.

[0050] (5) In the above embodiment, the gas is air pressurized by the compressor Cp and sent to the first gas cylinder AS1 and the second gas cylinder AS2. As another configuration, as shown in Figure 3, the fuel gas, which is a fluid to be controlled to a set pressure, may be configured so that the fuel gas on the primary side of the pressure control valve Vc can be pressurized as a gas and sent to the first gas cylinder AS1 and the second gas cylinder AS2. Specifically, a configuration can be adopted in which the upstream sides of the first gas flow path L1 and the second gas flow path L2 are connected in communication with the primary side of the pressure control valve Vc in the fluid flow path 1. In the configuration example shown in Fig. 3, the upstream sides of the first gas flow path L1 and the second gas flow path L2 are connected in communication with the upstream flow path portion 5u of the branching and merging flow path 5. The downstream side of the first throttle A1 of the third gas flow path L3 and the downstream side of the second throttle A2 of the fourth gas flow path L4 are connected to each other, and are provided with a temporary storage tank T. That is, the temporary storage tank T is configured to be able to store fuel gas as gas that is pressure-fed to the first gas cylinder AS1 and the second gas cylinder AS2 and then discharged from the first gas cylinder AS1 and the second gas cylinder AS2. Furthermore, the temporary storage tank T is equipped with a discharge flow path L5 that connects its interior with the secondary side of the pressure control valve Vc of the fluid flow path 1, and a discharge flow path opening / closing valve VE3 that opens and closes the discharge flow path L5. When the discharge flow path opening / closing valve VE3 is provided inside the building BK3, it is preferable that the discharge flow path opening / closing valve VE3 have a fourth explosion-proof structure BK4 made up of an explosion-proof case or the like. When the pressure measured by the secondary pressure sensor P (an example of a secondary pressure measuring unit) is less than a predetermined discharge threshold (for example, the set pressure of the pressure control valve Vc (for example, a pressure of about 2.3 kPaG), or a pressure of about 90% of the set pressure of the pressure control valve Vc), the control device S changes the discharge flow path opening / closing valve VE3 from a closed state to an open state, and performs discharge control to discharge the fuel gas stored in the temporary storage tank T to the secondary side of the fluid flow path 1.

[0051] Furthermore, the configurations disclosed in the above embodiments (including other embodiments, the same applies below) can be applied in combination with configurations disclosed in other embodiments, as long as no contradictions arise. Furthermore, the embodiments disclosed in this specification are examples, and the embodiments of the present invention are not limited to these, and can be modified as appropriate within the scope that does not deviate from the purpose of the present invention. [Industrial Applicability]

[0052] The pressure control device of the present invention does not require an explosion-proof structure, allowing for greater design freedom, and can be effectively used as a pressure control device that can adjust the rotation angle with relatively high precision while allowing operation with simple control. [Explanation of symbols]

[0053] 1: Fluid flow path 2: Pressure setting spring 3: Pressure adjustment screw 100: Pressure control device A1: First aperture A2: Second aperture AS1: First gas cylinder AS2: Second gas cylinder BK1: 1st explosion-proof structure BK2: 2nd explosion-proof structure Cp: ​​Compressor G1: 1st ratchet gear G2: Second ratchet gear K: Rotation angle setting mechanism K1: Mechanical drive unit K2: Gas flow adjustment section L1: First gas flow path L2: Second gas flow path L5: Discharge flow path NL1: First engaging claw NL2: Second engaging claw P: Secondary pressure sensor RH: Rotation resistance part RR: Rotation control unit S: Control device T: Temporary storage tank VE1: First solenoid valve VE2: Second solenoid valve VE3: Discharge flow path on-off valve Vc: Pressure control valve Vp: Pilot valve X1: 1st direction X1a: 1st rotation direction X2 :Second direction X2a: Second rotation direction

Claims

1. a pressure control valve that controls a secondary pressure of a fluid flow path through which the fluid flows to a set pressure; a pressure setting unit that changes and sets the set pressure, The pressure setting unit is a pressure control device including a pressure setting spring that can change and set the set pressure by adjusting a spring load, a rotation angle setting mechanism that can set a rotation angle of a pressure adjustment screw that can adjust the spring load, and a control unit that controls the rotation angle setting mechanism, The rotation angle setting mechanism includes: a first ratchet gear that can rotate the pressure adjusting screw in a first rotation direction; a first engagement pawl that, when moving forward in a first direction along the first direction, is brought into an engaged state in which it engages with the first ratchet gear, causing the first ratchet gear to rotate in the first rotational direction, and that, when moving backward in the first direction along the first direction, is brought into a disengaged state in which it does not engage with the first ratchet gear; a second ratchet gear that can rotate the pressure adjusting screw in a second rotation direction that is opposite to the first rotation direction; a second engagement pawl that, when moving forward in the second direction along the second direction, is brought into an engaged state in which it engages with the second ratchet gear, causing the second ratchet gear to rotate in the second rotational direction, and that, when moving backward in the second direction along the second direction, is brought into a disengaged state in which it does not engage with the second ratchet gear; a first gas cylinder that is capable of projecting and moving forward in the first direction and of retracting and pulling back the first engagement claw backward in the first direction; and a second gas cylinder that is capable of projecting and moving forward in the second direction and of retracting and pulling back the second engagement claw backward in the second direction. A pressure control device comprising: a gas flow adjustment unit that adjusts the pressure supply of gas to the first gas cylinder when the protruding movement occurs and the discharge of gas from the first gas cylinder when the retracting movement occurs, and that adjusts the pressure supply of gas to the second gas cylinder when the protruding movement occurs and the discharge of gas from the second gas cylinder when the retracting movement occurs.

2. As the gas flow adjusting unit, a first gas flow path that pressurizes the gas to the first gas cylinder so as to move the first engagement claw forward in the first direction, and a first electromagnetic valve that can open and close the first gas flow path; a second gas flow path that pressurizes the gas to the second gas cylinder so as to move the second engagement claw forward in the second direction, and a second electromagnetic valve that can open and close the second gas flow path; the control unit controls the first solenoid valve to be in an open state when the first engagement claw is moved forward in the first direction, 2. The pressure control device according to claim 1, wherein the second solenoid valve is controlled to be in an open state when the second engaging claw is moved forward in the second direction.

3. 3. The pressure control device according to claim 2, wherein the first solenoid valve and the second solenoid valve have an explosion-proof structure.

4. 3. The pressure control device according to claim 1, wherein the rotation angle setting mechanism has a rotation resistance portion on the rotation shaft of the pressure adjusting screw that resists rotation of the pressure adjusting screw in the first rotation direction or the second rotation direction.

5. the rotation angle setting mechanism is provided between the first ratchet gear and the pressure adjusting screw, and between the second ratchet gear and the pressure adjusting screw, without interposing a clutch therebetween; The pressure control device according to claim 1 or 2, further comprising a rotation operation part that allows the pressure adjustment screw to be manually rotated in the first rotation direction or the second rotation direction.

6. 3. The pressure control device according to claim 1, wherein air compressed by a compressor is pressure-fed to the first gas cylinder and the second gas cylinder.

7. 3. A pressure control device as described in claim 1 or 2, wherein the fuel gas, which is the fluid to be controlled to the set pressure, is on the primary side of the pressure control valve and is configured to be pressurized and fed to the first gas cylinder and the second gas cylinder as the gas.

8. a temporary storage tank capable of storing the fuel gas as the gas discharged from the first gas cylinder and the second gas cylinder after being pressure-fed to the first gas cylinder and the second gas cylinder; a discharge flow path connecting the temporary storage tank and a secondary side of the fluid flow path; a discharge flow path opening / closing valve that opens and closes the discharge flow path; a secondary pressure measuring unit capable of measuring the pressure on the secondary side of the pressure control valve, 8. The pressure control device according to claim 7, wherein, when the pressure measured by the secondary pressure measuring unit is less than a predetermined dischargeable threshold, the control unit changes the discharge flow path opening / closing valve from a closed state to an open state, and executes discharge control to discharge the fuel gas stored in the temporary storage tank to the secondary side of the fluid flow path.

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