JP3113715B2 - Valve device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve device, and more particularly to a ring device.
A plurality of sheet members formed in a coaxial manner
The present invention relates to a valve device configured to be inserted into a mounting hole of a valve body in a state .

[0002]

2. Description of the Related Art As a conventional valve device, there is, for example, a valve structure applied to a pressure control device for controlling a supply pressure of city gas. In this type of valve structure, each seat such as a seat ring, a cylindrical cage, a retainer for guiding a valve inserted into the cage, and the like is formed in a mounting hole provided in the middle of the flow path in the valve body. After each member is inserted one by one, a valve shaft holding member, which is called a bonnet and supports the valve shaft, is attached to the upper part of the valve body. Further, an annular gasket is interposed as a seal member between the lower surface of the valve shaft holding member and the upper portion of the valve body, and compresses the gasket by tightening a nut when fixing the valve shaft holding member to the valve body. At the same time, the sheet members are pressed and held from above.

[0003]

However, in the above-mentioned conventional construction, since the seat members are pressed from above by tightening the nuts of the valve shaft holding member in a state where the respective seat members are stacked , each seat member is inspected. Since the parts are disassembled at the time of repair, and each one is assembled to the valve body one by one at the time of inspection and repair, the assembling work is troublesome and troublesome, and the skill is required to assemble while managing each dimension. There is.

Accordingly, an object of the present invention is to provide a valve device that solves the above-mentioned problems.

[0005]

According to the first aspect of the present invention, the valve is formed by coaxially superposing a plurality of annularly formed sheet members and a plurality of annularly formed sheet members in communication with a pipe through which fluid is supplied. A valve seat member inserted into the mounting hole of the main body, a valve body inserted into the valve seat member to open and close a flow path provided in the valve seat member, and a valve shaft of the valve body are held. In a valve device having a valve shaft holding member fixed to the valve body, a first fixing member for integrally fixing a plurality of seat members constituting the valve seat member in a coaxially stacked state. Is provided .

[0006] The invention according to claim 2 is the first fixing portion.
The plurality of seat members integrated by the material are
A second fixing member fixed to the holding member is provided .

[0007]

SUMMARY OF] According to the invention of the first aspect, integral multiple sheet members constituting the valve seat member in a state of overlapping coaxially
Since the first fixing member for temporarily fixing is provided , the first fixing
To prevent multiple valve seat members from falling apart
Unitized and easy to assemble to valve shaft holding member
I can do it . In addition, during inspection and repair, multiple members can be removed as a single unit for maintenance.
The performance is improved .

According to the second aspect of the present invention, the first fixed member is provided.
The plurality of seat members integrated by the
Since the second fixing member for fixing to the shaft holding member is provided , the plurality of sheet members are separated by the first fixing member.
Since it is assembled <br/> Rukoto to leave the valve shaft holding member fixed state so as not, with can be easily is assembling and detaching operations, assembly of a plurality of sheet members after assembly precision And maintainability is improved .

[0009]

1 to 5 show a pressure control device to which an embodiment of a valve device according to the present invention is applied. In each of the drawings, a pressure control valve device is provided, for example, in the middle of a pipe for supplying city gas. A shutoff valve mechanism 2, a pressure control valve mechanism (having essential parts of the present invention) 3, and a strainer 4 are generally provided in a valve device main body 1. Be attached.

The shutoff valve mechanism 2 and the pressure control valve mechanism 3 are unitized by using one valve device main body 1 as a common main body, and the entire device has a more compact configuration. The valve device main body 1 has an inlet side flange 1a and an outlet side flange 1b at the bottom. At the center of the inlet side flange 1a, an inlet 1c connected to an upstream pipe (not shown) is opened.
An outlet 1d connected to a downstream pipe (not shown) opens at the center of the outlet flange 1b. A substantially inverted U-shaped flow path 5 is provided inside the valve device body 1, and a strainer mounting section 5a, a shutoff valve mounting section 5b, and a pressure control valve mounting section 5c are provided in the middle of the flow path 5. .

The strainer 4 is formed by forming a mesh-like wire mesh into a cylindrical shape, and has an upper opening 1e on the inlet 1a side of the valve device main body 1.
It is further inserted into the strainer mounting portion 5a. When the lid 6 in the upper opening 1e is secured by tightening the bolt 6b, on the strainer 4, a lower end portion is held by the inner wall step portion 5a ₁ of the lower depression 6a and the strainer mounting portion 5a of the lid 6. Therefore, the gas flows upward and downward from the strainer 4.
After flowing into the lower opening, it passes through the mesh and flows out toward the outer periphery of the stoner 4.

[0012] shutoff valve attachment portion 5b is located downstream of the strainer 4, the valve seat member 7 to the wall portion 5b ₁ which defines a flow path 5 is screwed. Further, a shutoff valve mechanism 2 is attached to an upper opening 1f that opens above the shutoff valve attachment portion 5b. The shut-off valve mechanism 2 includes a pressure detection unit 8 that detects a change in the secondary pressure at the outlet 1d side, and an unlocking unit that performs an unlocking operation of the valve shaft 9 when the pressure detection unit 8 detects an increase in the secondary pressure. 10 and a locking portion 11 for locking the valve shaft 9 at a raised position (valve opening position). A valve seat member 7 is provided at the lower end of the valve shaft 9.
Is provided with a valve body 12 which is detached and seated. The casing 2 a of the shut-off valve mechanism 2 is fixed to the upper surface of the main body 1 via the mounting base 13 by tightening bolts 14. In addition, a seal member (not shown) that seals between the upper opening 1f and the valve shaft 9 is attached to the mounting base 13.

Normally, the valve element 12 of the shut-off valve mechanism 2 is raised to a valve-open position separated from the valve seat 7a of the valve seat member 7, as shown in FIG. Then, as shown in FIG. 3, the secondary pressure P ₂
Is a secondary pressure detection pipe 15 connected to the connection port 15 of the main body 1
a, and a connection pipe 16 connected to the lower chamber 8a of the pressure detector 8.
And is introduced into the pressure detecting unit 8 via As shown in FIG. 2, the pressing force of Beroufuramu 17 was introduced into the pressing force and the lower chamber 8a of the coil spring 18 provided in the upper chamber 8b 2 primary pressure P ₂ defining an interior of the pressure detecting section 8 Is in a balanced position. The spring force of the coil spring 18 is set to an arbitrary value by adjusting the screwing position of the spring retainer 19. Note that the detection pressure set by the pressure detection unit 8 is equal to or higher than the pressure set by the pressure control valve mechanism 3.

Therefore, when the downstream secondary pressure P ₂ rises above the set pressure, the pressure in the lower chamber 8a rises, so that the bellow flam 17 of the pressure detector 8 is connected to the upper plate 17a.
Together with the lower plate 17b against the pressing force of the coil spring 18. At the same time, the shaft 20 of the unlocking section 10 moves upward.
When the shaft 20 starts to move upward, the first spring 21 on the outer peripheral side and the second spring 22 on the inner peripheral side are compressed. Thus, the pressing force for lifting the hook 23 is reduced by the first spring 21.
And the resultant force of the second spring 22 and the spring force of the second spring 22 are larger than the force for locking the needle 25 (frictional force with the locking ball 26).

As described above, the pressing force for moving the hook 23 upward is rapidly increased to cause a toggle effect, and the hook 23 moves upward together with the plunger 24. As a result, needle 2
5 is removed from the valve shaft 9, and the locking ball 26 is moved to the valve shaft 9.
Is displaced inward. Therefore, the valve shaft 9 is released from the locking by the locking ball 26, and moves downward vigorously by the pressing force of the spring 27.

As described above, when an abnormal pressure rise occurs on the downstream side, the valve element 12 is seated on the valve seat 7 by the operation of the pressure detecting section 8 and the unlocking section 10, and the flow path 5 is shut off. .
The return operation when returning to the open state after the valve is closed is only to rotate the shaft 28 shown in FIG. 3 clockwise. Since the shaft 28 has the claw 28a that engages with the pin 9a of the valve shaft 9, the pin 9a is pushed upward by the rotation, and the valve shaft 9 is raised to the valve opening position. Therefore, the valve shaft 9 is locked by the needle 25 and the locking ball 26 again.

As shown in FIGS. 1 and 4, the pressure control valve mechanism 3 is provided with a pressure control valve mounting portion 5 on the downstream side of the shutoff valve mechanism 2.
c. The pressure control valve mechanism 3 includes a pressure detecting unit 30 mounted on the upper surface of the main body 1, a valve shaft 31 driven by the pressure detecting unit 30, a valve shaft holding member 35 for holding the valve shaft 31, a valve shaft holding It comprises a valve seat unit (valve seat member) 32 fixed to the fitting portion 35 a of the member 35 and a valve body 33 provided at the lower end of the valve shaft 31. Valve shaft holding member 3
5 is the lower end of the valve seat unit 32 and the step 5 of the mounting portion 5c.
c ₁ , the fitting portion 35 a is fitted in the mounting hole 1 g, and is fixed to the upper surface of the main body 1 by tightening the nut 34.

The valve shaft holding member 35 has a fitting portion 35a projecting from the center of the lower surface of a contact portion 35b contacting the upper surface of the main body 1, and an O-ring 36 is attached to the outer periphery of the fitting portion 35a. . Therefore, when the fitting portion 35a is inserted into the mounting hole 1g of the main body 1, the gap between the fitting portion 35a and the main body 1 is sealed by the O-ring 36 regardless of the tightening state of the nut 34, and the plurality of nuts 34 There is no risk of leakage due to variations in tightening torque.

As shown in FIG. 5, the valve seat unit 32 has an annular seat ring 37 abutting on the pressure control valve mounting portion 5c.
A valve seat packing 38 mounted on the upper surface of the seat ring 37;
8 comprises a plurality of seat members such as a cylindrical cage 39 for holding the valve shaft 8 and a retainer 41 for guiding the valve shaft 31 over the upper end of the cage 39 via a seal member 40. Soshi
The seat ring 37 and the valve which constitute the valve seat unit 32
The seat packing 38, the cage 39, and the retainer 41 are each a ring.
And mounted on the valve shaft holding member 35.
Before that, they are integrated in a state where they are coaxially overlapped in advance.

The seat ring 37 has a flow path 37a penetrating in the vertical direction, and a valve seat 37b at the upper peripheral edge of the flow path 37a.
A large-diameter flange portion 37c on the outer peripheral side of the valve seat 37b;
Groove 3 provided on the upper surface of 7c and fitted with the lower end of cage 39
7d, and an O-ring 37e for sealing between the outer periphery and the mounting portion 5c is attached to the outer periphery. The flange portion 37c is provided with a plurality of screw holes 37f.

[0021] Also, the cage 39 has a plurality of passages 39a to the valve body 3 3 is bored in a radial direction so as to communicate the inner wall and the outer circumferential surface that slides. Accordingly, the valve element 3 3 through the outer peripheral side of the gas a plurality of passages 39a of the cage 39 when separated from the valve seat 37b of the seat ring 37 flows into the flow path 37a of the seat ring 37. The retainer 41 has a guide hole 41a vertically penetrating at the center, a protrusion 41b at the lower end which fits into the upper opening 39b of the cage 39 and compresses the seal member 40 , and a large-diameter flange 41c at the upper end. Having. The guide hole 41a is a valve element 3 without play stably guide, the outer periphery of the valve element 3 3 assembled piston ring 31a in sliding contact with the inner wall of the guide hole 41a, escape for reducing the sliding resistance Is provided with a small diameter portion 31b.
Further, the valve body 3 3 of holes 31c for releasing the center portion with the upward movement of the valve body 3 3 of gas in the guide hole 41a of the retainer 41 to the downstream side penetrates.

An O-ring 42 for sealing the space between the retainer 41 and the valve shaft holding member 35 is mounted on the upper surface of the retainer 41, and a plurality of first bolt insertion holes 41d are vertically formed on the outer side thereof. ing. Reference numeral 43 denotes a bolt (first fixing member) for integrating the members of the valve seat unit 32, which is inserted into the bolt insertion hole 41d of the retainer 41 and screwed into the screw hole 37f of the seat ring 37. This bolt 43
Are arranged at 90 ° intervals in the circumferential direction of the valve seat unit 32. When the four bolts 43 are tightened into the screw holes 37f, the seat ring 37, the cage 39, and the retainer 41 serving as the seat members are stacked in the vertical direction before being assembled to the valve shaft holding member 35. And are integrated.

As shown in FIG. 6, a unitized valve seat unit 3 is provided on the lower surface of the fitting portion 35a of the valve shaft holding member 35.
2 are provided with a plurality of screw holes 35c. Further, a second bolt insertion hole 41e communicating with the screw hole 35c is formed in the flange 41c of the retainer 41.
The second bolt insertion holes 41e are formed so as to be alternate with the first bolt insertion holes 41d.

As described above, the seat ring 37, the cage 39, and the retainer 4 are previously tightened with the four bolts 43.
The valve seat unit 32 in which the first unit 1 is integrated is attached to a mounting bolt (the first
The second fixing member 44 is fixed to the lower surface of the fitting portion 35a of the valve shaft holding member 35 by screwing the 44 into the screw hole 35c from the second bolt insertion hole 41e. In this state, the valve shaft 31
Penetrates a bearing member 35d press-fitted into a central hole 35c of the valve shaft holding member 35, and is vertically movably supported. A seal member such as an O-ring for sealing between the valve shaft 31 and the valve shaft holding member 35 is attached to the inner and outer circumferences of the bearing member 35d. Accordingly, the valve seat unit 32 is easily assembled and removed from the main body 1 together with the valve shaft holding member 35, so that inspection, disassembly and assembly work at the time of repair can be performed efficiently.

Therefore, the valve seat unit 32 is connected to the shaft holding member 3.
By integrally attaching to the fitting portion 35a of 5, the assembling work can be easily performed, and at the time of inspection and repair, the maintenance property is improved, so that even an inexperienced worker can efficiently perform inspection and repair. In addition, the valve seat unit 32 includes various members (seat ring 37, valve seat packing 38, cage 39,
Since the retainer 41) can be checked from the outside in the assembled state, it is easy to find an abnormality, and the reliability and safety are further improved. Further, as shown in FIG. 5, by preparing a valve seat unit 32 assembled in advance, check the factory performs only exchange of the valve seat unit 32 in the installation site, it is possible to perform the repair, installation No on-site maintenance is required, and the on-site work time is reduced.

The pressure detecting section 30 includes a pilot section 45 for detecting a change in the secondary pressure P ₂ , and an actuator section 46 for driving the valve body 33 in the valve opening direction when an operating pressure is supplied from the pilot section 45. And As will be described later, the pilot section 45 has a sudden
And supplies the actuator unit 46 to the primary pressure P ₁ when the next pressure P ₂ decreases as the operating pressure. Thus, the actuator unit 46 because the operating pressure is increased, relative to the pressure change in the secondary pressure P _2, to drive the good response valve body 33.

As shown in FIG. 7, the pilot section 45 of the pressure detecting section 30 includes an upper member 47, an intermediate member 48, and a lower member 49.
The members 47 to 49 are integrally fixed by tightening a plurality of bolts 50. Between the upper member 47 and the intermediate member 4 8, the upper chamber internal pilot portion 45 6
1 and an upper diaphragm 52 that defines a middle chamber 62 are interposed. The upper diaphragm 52 is clamped between the connecting member 53 and the diaphragm retainer 54 by tightening a nut 55. The upper diaphragm 52 is urged downward by the pressing force of the coil spring 56. A spring retainer 57 of a coil spring 56 is screwed into the upper opening 47a of the upper member 47. The pressure value when the upper diaphragm 52 moves upward is determined by the spring retainer 5 that contacts the upper end of the coil spring 56.
It is adjusted by changing the spring force by moving up and down 7.

A lid member 58 is screwed into the upper end of the upper opening 47a of the upper member 47, and a rectangular through hole formed in the center of the spring retainer 57 is inserted into the center hole 58a of the lid member 58. A rod 59 inserted into the hole 57a is rotatably mounted. The rod 59 has a hexagonal head 58 at the upper end.
a, and a retaining ring 64 for preventing slipping out which comes into contact with the lower surface of the lid member 58 is fitted in the middle, and has an engaging surface 59b that engages with the through hole 57a of the spring retainer 57 from the middle part to the lower end. Therefore, by turning the head 59a of the rod 59 using a tool such as a wrench, the spring pressure 57 can be moved up and down to adjust the operating pressure. The upper member 47 has an upper chamber 6.
1 is provided with an air port 47a communicating with the diaphragm 5;
The discharge and inflow of the air accompanying the up and down movement of 2 are performed via the air port 47a.

The intermediate member 48 is provided on the left side wall in FIG.
Has a primary pressure supply passage 48a to the next pressure P ₁ is introduced,
To supply the working pressure P _L in the middle chamber 62 to the right side wall,
That has a passage 48b for supplying the deterioration during primary pressure P ₁ of the secondary pressure P _2. The primary pressure supply path 48a extends to the center of the middle chamber 62, and a nozzle 65 provided downward is provided at an end thereof.

Between the intermediate member 48 and the lower member 49, a seal member 66 for sealing between the two members, and a lower diaphragm 67 for defining the inside of the pilot portion 45 into the middle chamber 62 and the lower chamber 63 are interposed. I do. The lower diaphragm 67 is clamped between the diaphragm retainer 69 and the pilot valve 70 by tightening the nut 68. Pilot valve 70 is nozzle 6
When the secondary pressure P ₂ opposes the pressure 5, the secondary pressure P ₂ moves downward and separates from the nozzle 65 to introduce the primary pressure P ₁ from the nozzle 65 into the intermediate chamber 62 as described later. The pilot valve 70 is connected to the upper diaphragm 52 via a connecting member 53, and the upper and lower diaphragms 52 and 67 move up and down integrally. When the pilot valve 70 is in contact with the nozzle 65 and is closed at the center of the pilot valve 70, the pilot valve 70 moves downward by the pressure of the primary pressure P ₁ and enters the lower chamber 63 into the lower chamber 63. sub-valve unit 71 for supplying small amounts of pressure P ₁ are provided.

The lower member 49 has a fitting portion 49a projecting from the bottom.
An O-ring 72 provided on the outer periphery of the fitting portion 49a;
Communication hole 49b penetrating through fitting portion 49a and communicating with lower chamber 63
And As shown in FIG. 6, the actuator portion 46 has a cover 73 fixed to the upper surface of the valve shaft holding member 35, and an upper chamber 74 and a lower chamber 75 between the valve shaft holding member 35 and the cover 73. And a bellow fram 76 interposed therebetween. This bellow frame 76 is a valve shaft 3
1 is sandwiched between a disk-shaped bellow fram receiving member 77 and a bellow flam holding member 78 attached to the upper end of the disk. Beroufuramu receiving member 7 7 is placed on the flange portion 79a of the mounting member 79 to be fitted to the valve stem 31, Beroufuramu 76 by tightening the nut 80 which is screwed to the upper end of the valve stem 31 valve stem 31 and the valve body 33 And integrated.

Further, the bellows frame pressing member 78 is urged downward by the pressing force of the coil spring 81. The spring force of the coil spring 81 is adjusted by vertically moving a spring retainer 82 (see FIG. 7) screwed into the upper opening 73a of the cover 73. In the center of the spring retainer 82, a communication hole 82a communicating with the lower chamber 63 of the pilot section 45 is formed.
6 is communicated with the upper chamber 74 through the communication holes 49b and 82a of the lower member 49 and the spring retainer 82, and has the same pressure.

When the pressure in the lower chamber 75 becomes larger than the combined force of the pressure in the upper chamber 74 and the spring force of the spring 81, the actuator 46 moves the bellow frame 76 upward to open the valve shaft 31 and the valve body 33. Drive in the direction. As shown in FIG. 4, on the upstream side of the pressure control valve mounting portion 5c provided with the pressure control valve mechanism 3, a primary pressure take-out passage 83 is drilled upward. Member 35 and cover 7
3 and communicate with communication holes 84 and 85 formed in the same. The communication hole 85 is connected to the primary pressure supply passage 48 a of the pilot section 45 via a pressure supply pipe 86. The passage 48b of the pilot section 45 is connected to a lower chamber 75 of the actuator section 46 via an operating pressure supply pipe 87.
The working pressure supply pipe 87 has a downstream pipe (FIG. 4).
Among, indicated by the one-dot chain line) 88 Secondary pressure supply conduit 89 is connected branched from the aperture 90 narrowing the pressure of the secondary pressure P ₂ is disposed in the conduit 89. The pipe 89 is connected to the upper chamber 74 of the actuator 46 via the branch pipe 91.
Is connected to

As shown in FIG. 1, a manual opening / closing valve 92 and a pressure gauge 93 for measuring the pressure value of the primary pressure P ₁ are provided in the pressure supply line 86. Is normally open. The pressure control valve device having the above-mentioned configuration is provided with a strainer 4, a shut-off valve mechanism 2,
Since the pressure control valve mechanism 3 is mounted and unitized, there is no need to transport each part separately and assemble it on site. It is only necessary to transport the parts as assembled at the factory and install them at the installation site. Therefore, hook members 96 and 97 are provided at both ends of the upper surface of the valve device main body 1 for passing wires or hooks (not shown) when using a crane or the like.

Therefore, the installation work at the installation site is considerably simplified, and the construction period is shortened. Further, the apparatus since Ru Ah with a compact structure and reduced components of the entire apparatus requires a small installation space, which is advantageous in terms of land secured. Furthermore, according to the configuration of the above device, maintenance after installation,
In an inspection or the like, for example, the bolts 6b, 14, and 34 can be removed, and the stoner 4, the shutoff valve mechanism 2, and the pressure control valve mechanism 3 can be independently removed. Therefore, only the mechanisms 2 and 3 are detached from the valve device main body 1 during maintenance and inspection and repair can be performed as appropriate, so that maintenance work can be easily performed. Here, the pressure control operation of the pressure control valve mechanism 3 configured as described above will be described. In FIG. 4, the valve body 33 of the pressure control valve mechanism 3 is at a valve closed position in contact with the seat ring 37, the flow path 5 in the valve device main body 1 is shut off, and the gas supply is stopped. For example, gas consumption in the morning or evening or the like downstream is increased secondary pressure P ₂ decreases. This secondary pressure P ₂ is introduced into the upper chamber 74 of the actuator section 46 via the secondary pressure supply pipe 89 and the branch pipe 91. Accordingly, the pressure P _a in the upper chamber 74 when the secondary pressure P ₂ decreases is reduced.

Further, the upper chamber 74 is provided with a pilot section 45.
And the pressure P _b in the lower chamber 63
Also decrease. That is, the upper diaphragm of the pilot unit 45
Since the arm 52 and the lower diaphragm 67 are connected by the connecting member 53, the pressure P _b is smaller than the pressing force of the spring 56 of the pilot portion 45, the pressure P _c of the upper chamber 61
Is the atmospheric pressure, the pair of diaphragms 52 and 67 move downward.

Accordingly, the pilot valve 70 provided on the lower diaphragm 67 is separated from the nozzle 65. Because the nozzle 65 where the primary pressure P ₁ in the flow path 5 is supplied through the passage 83, the communication hole 84, 85 and line 86,1 primary pressure supply passage 48a, the valve opening operation of the pilot valve 70 Operating pressure P _L in the intermediate chamber 62 of the pilot section 45
Rises.

The increased operating pressure P _L is supplied to the lower chamber 75 of the actuator section 46 through the pipe 87. Therefore, the pressure P _d in the lower chamber 75 primary pressure P _1, and the upper chamber 7
4 the pressure P _a (reduced secondary pressure P ₂₎ of and larger than the resultant force of the pressing force of the spring 81. Thus, the pressure P _d of the lower chamber 75 with the pressure P _a of the upper chamber 74 in the actuator unit 45 is lowered to increase the primary pressure P _1, Beroufuramu 76 integral with Beroufura This pressure difference <br The drum receiving member 77 and the bellow ram pressing member 78 move upward. Further, the valve shaft 31 integrated with the bellows frame 76 moves upward to separate the valve body 33 from the seat ring 37.

Thus, the pressure control valve mechanism 3 is opened, the gas in the flow path 5 flows through the passage 39a of the cage 39 to the flow path 37a of the seat ring 37, and the downstream pipe 88
Supplied to A secondary pressure supply line 89 is connected to the working pressure supply line 87, but the secondary pressure supply line 8
9 is provided with a restrictor 90, and almost all of the increased operating pressure P _L of the middle chamber 62 is
5 is supplied to the lower chamber 75. Moreover, since the upper chamber 74 differential pressure P _L is supplied to the lower chamber 75 in the actuator unit 45 low pressure secondary pressure P ₂ is supplied, the upward movement operation of Beroufuramu 76 for reduction of the secondary pressure P ₂ is Fast and responsiveness has been significantly improved.

When the gas is supplied by the valve opening operation of the valve body 33, the secondary pressure P ₂ on the downstream side gradually increases, and then a predetermined pressure (a value set by the spring force of the spring 56 of the pilot portion 45). ) Is reached. Secondary pressure P ₂ is also increased pressure P _a in the upper chamber 74 of the actuator unit 46 via line 89, 91 when raised. Eventually, the pressure P _b (= P _a ) of the lower chamber 63 of the pilot section 45 communicating with the upper chamber 74.
Is larger than the spring force of the spring 56 provided in the upper chamber 61 of the pilot section 45, the pilot valve 70 integrated with the lower diaphragm 67 moves upward, comes close to the nozzle 65,
Squeezing the primary pressure P ₁ of the gas discharged from the nozzle 65 as a result, working pressure P _L is reduced pressure. This depressurized working pressure P _L is supplied to the lower chamber 75 of the actuator unit 46 via line 87, also decreases the pressure P _d of the lower chamber 75.

[0041] Therefore, when the pressure P _d of the lower chamber 75 is smaller than the resultant force of the spring force and the pressure P _a of the spring 81 of the upper chamber 74, the valve body pressure balance of the actuator unit 46 is reversed and the valve Hirakiji 33 moves down and the passage 39a of the cage 39 moves.
And the gap with the seat ring 37 is reduced, and the amount of gas supply to the downstream side is reduced. Thus, the pressure P _a and the pressure P _b of the lower chamber 75 of the upper chamber 74 of the actuator portion 46
Are adjusted with good responsiveness and high accuracy by controlling the operating pressure P _L of the pilot unit 45, so that the secondary pressure P ₂
Without causing hunting in response to the change, it performs a stable manner the pressure controlled by operating the valve 33 in the valve opening or valve closing direction secondary pressure P ₂ is set predetermined pressure .

In the above embodiment, the pressure control valve mechanism 3 has been described as an example. However, it goes without saying that the present invention can be applied to other valve devices.

[0043]

As described above, according to the first aspect of the present invention, the first fixing member for integrally fixing the plurality of seat members constituting the valve seat member in a coaxially stacked state is provided.
Due to the provision, by the first fixing member is a plurality of the valve seat member Bas
A valve shaft holding member that can be unitized so as not to fall apart
Assembly work can be easily performed . Further, at the time of inspection and repair, a plurality of members can be removed as one unit, so that the maintainability is improved . Furthermore, since each seat member constituting the main part of the valve device can be checked in the assembled state, abnormality of each member can be easily found, and reliability and safety can be improved.

According to the second aspect of the present invention, the first fixed member is provided.
The plurality of seat members integrated by the
Since the second fixing member for fixing to the shaft holding member is provided , the plurality of sheet members are separated by the first fixing member.
Since it can be assembled to the valve shaft holding member in a state where it is not fixed , the assembling work and the removing work can be easily performed , and the assembling accuracy of the plurality of seat members after the assembling can be secured , and Maintainability is improved . In addition, by preparing a unit in which a plurality of seat members are assembled to the valve shaft holding member in advance, it is only necessary to replace the unit without performing inspection and repair at the installation site, making maintenance work at the installation site unnecessary. As a result, the work time on site can be reduced.

[Brief description of the drawings]

FIG. 1 is a front view of a pressure control valve device to which an embodiment of a valve device according to the present invention is applied.

FIG. 2 is an enlarged longitudinal sectional view showing a configuration of a strainer unit and a shutoff valve mechanism of the pressure control valve device.

FIG. 3 is a partially cut-away side view of the valve device as viewed from a left side surface.

FIG. 4 is a longitudinal sectional view showing an internal configuration of a pressure control valve mechanism.

FIG. 5 is a longitudinal sectional view of a valve seat unit which is a main part of the present invention.

FIG. 6 is an enlarged longitudinal sectional view showing an actuator section and a valve seat unit.

FIG. 7 is an enlarged longitudinal sectional view showing a pilot unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Valve apparatus main body 2 Shut-off valve mechanism 3 Pressure control valve mechanism 4 Strainer 5 Flow path 7 Valve seat member 8 Pressure detector 9 Valve shaft 10 Lock release part 11 Lock part 12 Valve element 30 Pressure detector 31 Valve shaft 32 Valve Seat unit 33 Valve shaft holding member 37 Seat ring 38 Valve seat packing 39 Cage 40 Seal member 41 Retainer 43 Bolt 44 Mounting bolt 45 Pilot part 46 Actuator part 52 Upper diaphragm 57 Spring retainer 59 Rod 61 Upper chamber 62 Middle chamber 63 Lower chamber 67 Lower diaphragm 70 Pilot valve 71 Sub-valve 73 Cover 74 Upper chamber 75 Lower chamber 76 Bellows 83 Primary pressure extraction passage 84, 85 Communication hole 86 Pressure supply pipe 87 Working pressure supply pipe 88 Downstream pipe 89 Secondary pressure Supply line 90 throttle

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Seiko Kobayashi 1-3-6 Fujimi, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Tokiko Corporation (72) Inventor Akio Ishii 1-6-1, Fujimi, Kawasaki-ku, Kawasaki-ku, Kanagawa No. 3 Inside Tokiko Corporation (56) References JP-A-60-14661 (JP, A) JP-A-59-25749 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G05D 16/00-16/20

Claims (2)

(57) [Claims] 1. A valve seat member inserted into a mounting hole of the valve body by coaxially stacking a plurality of annularly formed sheet members with a valve body communicating with a pipe through which fluid is supplied. A valve body inserted into the valve seat member to open and close a flow path provided in the valve seat member; and a valve shaft holding member fixed to the valve body so as to hold a valve shaft of the valve body. A valve device comprising: a first fixing member for integrally fixing a plurality of seat members constituting the valve seat member in a coaxially stacked state. And the valve device. 2. The apparatus according to claim 1, wherein said first fixing member is integrated with said first fixing member.
A second fixing a plurality of seat members to the valve shaft holding member;
3. The valve device according to claim 1, further comprising a fixing member .