JP7260920B2 - Valve device and pressure reducing valve using the same - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve device that is provided in a fluid passage and adjusts the pressure of the passage by opening and closing the passage, and a pressure reducing valve using the same.

Various valve devices are arranged in the fluid passages to regulate the pressure in the passages (eg, US Pat. A direct-acting pressure reducing valve is opened and closed by one main valve, and a pilot-operated pressure reducing valve such as that disclosed in Patent Document 1 is opened and closed by one main valve and one pilot valve. Therefore, it is necessary to periodically disassemble the valve and perform maintenance such as replacement and cleaning of the valve. If regular maintenance is not performed, scale builds up on the valve, which can lead to steam leaks and the possibility of not being able to adjust the pressure on the secondary side.

JP-A-62-103717

However, maintenance requires disassembly of the device, which means that the device must be stopped. Therefore, it leads to opportunity loss, which is not preferable.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a valve device and a pressure reducing valve using the valve device that allows maintenance of the valve without disassembling the device.

In order to achieve the above object, the valve device of the present invention comprises a valve body that opens and closes between a fluid inflow path and a fluid outflow path, and a first spring body that causes the valve body to be seated on a valve seat by a spring force. a shaft member that presses the valve body in the valve opening direction to separate it from the valve seat; and a valve replacement unit that ejects the valve body that is in use and installs a new valve body at the use position. . The valve replacement unit includes: a plurality of valve body housing portions for housing the valve body; a valve body switching mechanism for switching between the plurality of valve body housing portions to move the valve body to the use position; and a cleaning area that contacts and cleans the valve body during movement.

According to this configuration, the valve replacement unit allows the valve body in use to be discharged and a new valve body to be installed. As a result, maintenance such as replacement and cleaning of the valve body can be performed without disassembling the device. In addition, the cleaning area allows replacement and cleaning without discarding the used valve body.

In the present invention, the plurality of valve body storage portions may be spaced apart in the circumferential direction of the rotation axis. According to this configuration, a plurality of valve bodies can be accommodated within a limited space.

A pressure reducing valve according to the present invention is a pressure reducing valve that is arranged in a main fluid passage and reduces the pressure on the primary side to the pressure on the secondary side. and a pilot valve unit for opening and closing. The pilot valve unit has the valve device of the present invention and a first valve drive section that presses the shaft member of the valve device in a valve opening direction to separate the valve body from the valve seat. . The first valve drive unit includes a second spring body that advances and presses the shaft member in the valve opening direction, and a spring force that receives the pressure from the secondary side and presses the second spring body. and a valve-closing force applying member that is retracted in the valve-closing direction against the valve-closing force applying member. Further, a second valve driving portion is provided for receiving the pressure of the outflow passage to open the main valve body, and the inflow passage of the valve device communicates with the primary side of the main passage.

According to this configuration, the valve replacement unit allows the valve body in use to be discharged and a new valve body to be installed, so maintenance of the valve body can be performed without disassembling the device.

According to the valve device and the pressure reducing valve of the present invention, maintenance of the valve body can be performed without disassembling the device, and replacement and cleaning can be performed without discarding the used valve body. .

1 is a longitudinal sectional view showing the basic configuration of a pressure reducing valve, which is the object of the present invention; FIG. It is a longitudinal cross-sectional view which shows typically the state before pressure_reduction|reduced_pressure of the same pressure-reduction valve. It is a longitudinal cross-sectional view which shows typically the pressure adjustment state of the same pressure-reduction valve. It is a longitudinal cross-sectional view which shows typically the pressure reduction holding state of the same pressure-reduction valve. 1 is a vertical cross-sectional view showing a main part of a valve device according to a first embodiment of the invention; FIG. It is a vertical cross-sectional view showing another state of the main part of the same valve device. It is a perspective view which shows the valve exchange unit of the same valve apparatus. (A) to (D) are front views showing procedures for replacing the valve body of the valve replacement unit of the same valve device. It is a side view which shows the turning drive part at the time of the valve body of the same valve apparatus. It is a front view which shows the cleaning area of the same valve apparatus. It is a perspective view which shows a mode that a valve body moves the same cleaning area. It is a front view which shows the modification of the cleaning area of the same valve apparatus.

Prior to describing embodiments of the present invention, a pressure reducing valve used in a steam passage will be described. In various industries, steam is used as a heat carrier from the viewpoint of cost, convenience and safety. The greatest advantage is that the latent heat per unit weight is large, and the temperature can be kept constant by controlling the pressure.

When using steam, instead of generating steam at each required pressure, a boiler generates high-pressure steam, and the steam is lowered to the required pressure according to the product or application. In that case, the automatic valve that keeps the steam pressure substantially constant is the pressure reducing valve. The purpose of lowering the pressure is to lower the steam temperature and keep it at the desired heating temperature.

The basic principle of decompression is called the throttling phenomenon. When steam flows through a pipe, if the passage through which the steam flows is throttled, the steam pressure on the downstream side becomes lower than the throttled point. This is the depressurization of steam. If it is just to throttle, there is a method of fixing the valve at an intermediate opening or providing an orifice plate, but this method has the problem that the pressure also changes when the flow rate changes. Therefore, even if the flow rate or the primary pressure (upstream pressure of the throttling point) changes, the secondary pressure (downstream pressure of the throttling point) does not fluctuate. A pressure reducing valve is a valve that is set to automatically change the valve opening by directly using .

Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the basic configuration of a pilot-operated pressure reducing valve, which is a type of pressure reducing valve using a valve device, which is the subject of the present invention. In FIG. 1, the pressure reducing valve is arranged in a main passage 1 through which steam S, which is a type of fluid, flows. A casing 2 of the pressure reducing valve PRV is formed by connecting a body case 4, an upper case 6 and a lower case 8. As shown in FIG. A primary side passage 10 , a secondary side passage 12 , and a valve chamber 14 therebetween are formed inside the body case 4 . The primary passage 10 and the secondary passage 12 form part of the main passage 1 through which the steam S flows. A valve holder 16 and a main valve element 18 that slides inside the valve holder 16 are arranged in the valve chamber 14 . The upper portion of the valve holder 16 is supported by the main body case 4 by screw connection.

The main valve body 18 contacts a main valve seat 22 formed in the valve holder 16 by a main spring body 20 made of a coil spring, and spring force is applied in the direction of closing the valve. A main valve driving section 24 for driving the main valve body 18 is arranged above the valve chamber 14 . The main valve driving portion 24 has a piston 26 that contacts the main valve element 18 and is slidably inserted into a cylinder 28 that is supported by the main body case 4 . Above the piston 26 is a main valve body driving chamber 27, which will be described later. The piston 26 is provided with a release hole 29 for releasing the pressure in the main valve body drive chamber 27 .

A pilot valve unit 30 is arranged above the upper case 6 . That is, the upper case 6 forms a casing of the pilot valve unit 30. As shown in FIG. The pilot valve unit 30 has a valve device 34 including a valve element 32 and a pilot valve driving section 36 for opening and closing the valve device 34 . The valve body 32 is, for example, a ball shape (sphere), but is not limited to this. The valve device 34 has a valve seat block 37, and a valve seat 40 is formed at its tip (left end in FIG. 1). A valve opening 41 that is opened and closed by the valve body 32 is opened in the central portion of the valve seat 40 .

A shaft member 42 is inserted through the valve seat block 37 in the front-rear direction (left-right direction in FIG. 1). A tip portion 42a of the shaft member 42 contacts the valve body 32, and a rear end portion 42b faces a tip plate 38 of the pilot valve drive portion 36, which will be described later. The valve body 32 is pressed against the valve seat 40 by a first spring body 44 made of a coil spring. The first spring body 44 is interposed between a first spring bearing 48 provided on the upper case 6 .

A tip plate 38 at the tip (left end in FIG. 1) of the pilot valve driving portion 36 is a second spring body made of a coil spring that extends from the rear (right in FIG. 1) to the front (left in FIG. 1). 54 is pressed. The second spring body 54 is interposed between a tip member 56 that contacts the tip plate 38 and a second spring retainer 58 that is arranged inside the cover member 50 . The cover member 50 is screwed to the upper case 6 (casing). A push rod 60 is arranged between the cover member 50 and the tip member 56 and passes through the inner space of the second spring body 54 .

The pilot valve driving section 36 has pressure adjusting means 49 . The pressure adjusting means 49 has the tip plate 38 and the bellows 43, and retracts the second spring body 54 in the valve closing direction (rightward direction). That is, the pressure adjusting means 49 constitutes a valve closing force applying member that retracts the second spring body 54 in the valve closing direction against the spring force.

A distal end portion 43 a of a bellows 43 is connected to the distal end plate 38 , and a proximal end portion 43 b of the bellows 43 is fixedly supported between the upper case 6 and the cover member 50 . An adjustment handle 52 for adjusting pressure is rotatably connected to the cover member 50 by screws.

A pilot chamber 62 that houses the first spring body 44 is arranged on the front side (left side) of the valve device 34 . The pilot chamber 62 communicates with the primary side passage 10 via a primary conduction passage 64 . A screen 66 for removing foreign matter is arranged in the pilot chamber 62 . A through passage 68 communicating with the valve port 41 is formed downstream of the valve body 32 in the valve device 34 . The pilot chamber 62 and the through passage 68 form an inflow passage and an outflow passage for the pilot valve unit 30, respectively. On the other hand, the secondary passage 12 communicates with the pressure introducing chamber 70 housing the pressure applying means 49 via the secondary conducting passage 72 .

Next, the operation of the above configuration will be explained.
[Before decompression]
FIG. 2 shows the state before the pressure reducing operation is started, and the main valve body 18 is in the closed state. When the steam S is passed through the pressure reducing valve, the steam S reaches the pilot chamber 62 from the primary passage 10 through the primary conduit 64 .

[Pressure adjustment]
When the adjustment handle 52 is rotated in the pressure reducing direction (counterclockwise), the push rod 60 of the pressure application means 49 moves forward (leftward) as shown in FIG. As a result, the bellows 43 expands and the tip plate 38 moves the shaft member 42 forward (to the left) to open the valve body 32 . As a result, the steam S flows into the outflow passage (through passage) 68 and pushes down the piston 26 to open the main valve body 18 . At this time, a slight gap G exists between the pressing plate 38 at the tip of the pressure applying means 49 and the back surface of the valve seat block 37 . By opening the main valve body 18, the steam S in the primary side passage 10 flows into the secondary side passage 12 and is decompressed.

[Holding of reduced pressure]
Part of the steam S that has flowed into the secondary passage 12 reaches the pressure introduction chamber 70 through the secondary conduit 72 as shown in FIG. The bellows 43 of the pressure application means 49 is compressed by the steam pressure in the pressure introduction chamber 70, and the tip plate 38 retreats rightward. As a result, the shaft member 42 is allowed to move rearward (rightward), and the valve body 32 is moved in the valve closing direction. By adjusting the pressure in the main valve drive chamber 27 in this manner, the degree of opening of the main valve 18 is adjusted, and the pressure in the secondary passage 12 is kept constant.

Next, the valve device 34, which is the essential part of the first embodiment of the present invention, will be explained with reference to FIGS. 5 to 12. FIG. The valve device 34 of this embodiment includes a valve replacement unit 80 . The valve replacement unit 80 ejects the valve body 32 in use and installs a new valve body 32 at the use position. The valve replacement unit 80 has a plurality of valve body housing portions 82 for housing the valve bodies 32 .

As shown in FIG. 8, in the present embodiment, six valve body storage portions 82 are provided spaced apart in the circumferential direction of the rotation axis AX. Specifically, the valve replacement unit 80 includes a columnar cylinder 86 centered on the rotation axis AX and a shaft body 88 having the rotation axis AX. Six circular through holes are formed spaced apart in the circumferential direction. The space formed by this through-hole constitutes the valve housing portion 82 . However, the number and arrangement of the valve body accommodating portions 82 are not limited to this.

As shown in FIG. 5 , the valve replacement unit 80 further has a valve body switching mechanism 84 that switches the valve body housing portion 82 . The valve body switching mechanism 84 of the present embodiment switches the valve body 32 (the valve body housing portion 82) by rotating the cylinder 86 around the rotation axis AX.

Specifically, the valve body switching mechanism 84 includes a turning driving portion 90 that rotates the cylinder 86 , an operating portion 92 that is operated by the user, and an operating force transmitting portion 94 that transmits the operating force of the operating portion 92 to the turning driving portion 90 . and

The operation section 92 operates the turning drive section 90 via the operation force transmission section 94 . The operating section 92 is exposed to the outside of the apparatus and is a section operated by the user. The operation unit 92 has push buttons 96 operated by the user. A spring body 98 imparts an upward spring force to the push button 96 . A connection portion 92 a to which the operation force transmission portion 94 is connected is formed on the lower surface of the push button 96 .

The operating force transmitting portion 94 includes a first link piece 100 extending vertically from the operating portion 92, a second link piece 102 extending from the first link piece 100 in the front-rear direction (horizontal direction in FIG. 5), and a and a third link piece 104 extending vertically from the second link piece 102 .

The upper end 100a of the first link piece 100 is connected to the connecting portion 92a of the operating portion 92 by a first pivot member 95 such as a connecting pin extending in the left-right direction (direction perpendicular to the plane of FIG. 5). there is A tooth portion (gear portion) 100b is formed on the rear surface of the first link piece 100 (the right side surface in FIG. 5).

The second link piece 102 has tooth portions (gear portions) 102a and 102b formed on its upper and lower surfaces, respectively. The second link piece 102 has its front end (left side in FIG. 5) connected to the lower portion of the first link piece 100 by a first gear 106 .

The first gear 106 is a cylindrical gear connected to a shaft body 106a having a rotation axis in the left-right direction (a direction perpendicular to the plane of FIG. 5). formed. The tooth portion 100b of the first link piece 100 and the tooth portion 102a on the upper surface of the second link piece 102 mesh with the tooth portion 106b of the first gear 106, so that the first link piece 100 and the second link are connected. Pieces 102 are connected. That is, the first gear 106 converts the vertical movement of the first link piece 100 into the longitudinal movement of the second link piece 102 (horizontal direction in FIG. 5).

The third link piece 104 has a tooth portion (gear portion) 104a formed on its front surface (right side surface in FIG. 5). The third link piece 104 is connected at its upper end to the rear end (left end in FIG. 5) of the second link piece 102 by a second gear 108 . Further, the lower end portion 104b of the third link piece 104 is connected to a turning driving portion 90, which will be described later, by a second shaft support member 105 such as a connecting pin extending in the left-right direction (direction orthogonal to the plane of FIG. 5). ing.

The second gear 108 is a cylindrical gear connected to a shaft body 108a having a rotation axis in the front-rear direction (a direction perpendicular to the paper surface of FIG. 5). formed. The lower tooth portion 102b of the second link piece 102 and the tooth portion 104a of the third link piece 104 mesh with the tooth portion 108b of the second gear 108, so that the second link piece 102 and the third link piece 102 are connected. A link piece 104 is connected. That is, the second gear 108 converts the longitudinal movement of the second link piece 102 (horizontal direction in FIG. 5) into vertical movement of the third link piece 104 .

8 supported by the third link piece 104 of the operating force transmission section 94, and a third gear 112 supported by the shaft 88. As shown in FIG. The locking pawl 110 is rod-shaped and its upper end is connected to the lower end 104 b of the third link piece 104 . A lower end portion of the locking claw 110 in FIG. 5 is bent rearward (to the left in FIG. 5) to form a claw portion 110a.

The third gear 112 is fitted on the shaft 88 at the center of the cylinder 86, as shown in FIG. That is, the third gear 112 rotates integrally with the cylinder 86 around the axis AX of the shaft body 88 . A gear 112 a is formed on the outer peripheral surface of the third gear 112 . The same number of gears 112a as the valve housing portion 82, which is six in this embodiment, is provided. The claw portion 110a of the locking claw 110 shown in FIG. 5 is engaged with the gear 112a.

The valve replacement unit 80 further has a spring force release portion 116 . The spring force release portion 116 releases the spring force of the first spring body 44 applied to the valve body 32 when rotating the cylinder 86 to switch the valve body housing portion 82 . The operating force transmission portion 94 of the valve replacement unit 80 has a fourth link piece 118 that transmits the operating force to the spring force releasing portion 116 .

The fourth link piece 118 has a rod-like shape extending vertically and is on the opposite side of the third link piece 104 with the second gear 108 interposed therebetween, that is, on the front side of the second gear 108 and the third link piece 104 (see FIG. 5). left). A tooth portion (gear portion) 118a is formed on the rear side of the fourth link piece 118 (on the right side in FIG. 5). The upper portion of the fourth link piece 118 is connected to the second link piece 102 by meshing the tooth portion 118 a of the fourth link piece 118 with the tooth portion 108 b of the second gear 108 . A spring force releasing portion 116 is connected to the lower end of the fourth link piece 118 by a third pivot member 115 such as a connecting pin extending in the left-right direction (direction orthogonal to the plane of FIG. 9).

The spring force release portion 116 has a link member 120 connected to the fourth link piece 118 and a spring engagement portion 122 that engages the first spring body 44 . The link member 120 is a vertically extending plate-like member, and its upper end is connected to the lower end of the fourth link piece 118 so as to be rotatable around the third pivot member 115 .

The spring engaging portion 122 is also a vertically extending plate-like member, and its upper end 122a is connected to the lower end of the link member 120 as a fourth connecting pin extending in the horizontal direction (direction perpendicular to the plane of FIG. 5). It is rotatably connected around the fourth shaft support member 125 via the shaft support member 125 . A lower end 122 b of the spring engaging portion 122 is connected to the first spring body 44 .

As shown in FIG. 5, the bulb replacement unit 80 further has a fall prevention cover 126. As shown in FIG. The fall-off prevention cover 126 prevents the valve body 32 from falling out of the valve body housing portion 82 when the valve body 32 (the valve body housing portion 82) is switched.

As shown in FIG. 7, the drop-off prevention cover 126 has a partially notched cylindrical shape, and includes a peripheral wall 126a covering the outer peripheral surface of the cylinder 86 and an end wall 126b provided at one end (front end) of the peripheral wall 126a. and The end wall 126b has an annular shape with a part notched. Specifically, the end wall 126b covers five of the six valve body housings 82 from the front side. The first spring body 44 is inserted through the notch 126 c of the drop-off prevention cover 126 .

The remaining one of the six valve body housings 82 is located behind the notch 126c in the end wall 126b and is not covered by the end wall 126b. The valve body 32 in use is housed in the valve body housing portion 82 at a position not covered by the end wall 126b. That is, the valve body housing portion 82 that houses the unused valve body 32 is covered from the front by the end wall 126b. A shaft 88 (FIG. 5) is inserted through the hollow hole 126d of the end wall 126b.

A detent projection 128 extending rearward is provided on the rear edge of the peripheral wall 126a. In this embodiment, the anti-rotation protrusion 128 is provided on the opposite side of the notch 126c of the end wall 126b (upper side in FIG. 7). The structure of the drop-off prevention cover 126 is not limited to the illustrated one.

The casing 6 shown in FIG. 5 is formed with a vertically extending key groove 130 with which the anti-rotation projection 128 is engaged. After the fall prevention cover 126 is attached to the cylinder 86 , the anti-rotation projection 128 is engaged with the key groove 130 . Thereby, the fall prevention cover 126 is non-rotatably supported.

Next, procedures for exchanging the valve body 32 of the valve device 34 of this embodiment will be described with reference to FIGS. In FIGS. 8A to 8D, the valve body housing portion 82 in which the valve body 32 in use is housed is referred to as a first valve body housing portion 82-1, and the first valve body housing portion 82-1 is opposite from the first valve body housing portion 82-1. The second to sixth valve body housing portions 82-2 to 82-6 are arranged clockwise.

First, the push button 96 of the operation unit 92 in FIG. 5 is operated downward (in the direction of arrow A1). As a result, the first link piece 100 of the operating force transmission portion 94 moves downward, the second link piece 102 moves rearward (to the right in FIG. 5) via the first gear 106, and the second gear 108 moves downward. , the third link piece 104 moves downward. The downward movement of the third link piece 104 causes the locking claw 110 of the turning drive portion 90 to move downward.

At this time, the fourth link piece 104 and the link member 120 of the spring force release portion 116 move upward (in the direction of arrow A4) via the second gear 108 . When the link member 120 moves upward, the spring engaging portion 122 rotates around the fourth pivot member 125, pulling the first spring body 44 forward (in the direction of arrow A5). As a result, the spring force of the first spring body 44 applied to the valve body 32 is released (FIG. 6). By releasing the spring force of the first spring body 44, the cylinder 86 becomes rotatable.

FIG. 8A shows the state of FIG. When the locking claw 110 of the turning drive unit 90 moves downward, the gear 112a of the third gear 112 of the turning driving unit 90 is pushed by the locking claw 110, and the cylinder 86 rotates in the A2 direction (clockwise) ( (B) in FIG. 8, the second valve housing portion 82-2 moves to the use position (lowest position) ((C) in FIG. 8). When the locking claw 110 moves further downward, the locking claw 110 separates from the gear 112a of the third gear 112 (FIG. 8(D)). FIG. 8D shows the state of FIG.

When the push button 96 in FIG. 6 is released, the spring force of the spring body 98 causes the push button 96 to return upward (in the direction of arrow A3). As a result, the first link piece 100 of the operating force transmission portion 94 moves upward, the second link piece 102 moves forward (to the left in FIG. 6) via the first gear 106, and the second gear 108 moves forward. , the third link piece 104 moves upward. As a result, as shown in FIG. 9, the locking pawl 110 moves forward (to the left in FIG. 9) around the second shaft support member 105 along the relief surface 112b formed on the gear 112a of the third gear 112. It rotates and disengages from the gear 112a and moves upward.

As a result, the state shown in FIG. 8A is restored. However, instead of the first valve housing portion 82-1, the second valve housing portion 82-2 is positioned at the use position (lowest). After that, when replacing the valve body 32, by repeating the above-described operation, the third valve body housing portion 82-3, the fourth valve body housing portion 82-4, the fifth valve body housing portion 82-5, the The valve body housing portion 82 installed at the use position is changed in the order of the 6 valve body housing portion 82-6, and the valve body 32 is replaced. At this time, the drop-off prevention cover 126 prevents the valve body 32 from dropping out of the valve body housing portion 82 .

The valve replacement unit 80 also has a cleaning area 114 for cleaning the valve body 32 when the valve body 32 is moved. Cleaning area 114 is provided in casing (upper case) 6 of pilot valve unit 30 . As shown in FIGS. 10 and 11, the cleaning area 114 is arc-shaped along the track of the valve body 32 . The cleaning area 114 is, for example, a resin brush or sponge. However, the cleaning area 114 is not limited to these. When the valve body 32 is replaced by the valve replacement unit 80 (FIG. 5), the cleaning area 114 cleans the valve body 32 .

According to the above configuration, the valve replacement unit 80 allows the valve body 32 in use to be discharged and a new valve body 32 to be installed. As a result, maintenance such as replacement of the valve body 32 can be performed without disassembling the device. Furthermore, since the valve replacement unit 80 has a cleaning area 114 that contacts and cleans the valve body 32 when the valve body 32 is moved, the valve body 32 is automatically cleaned when the used valve body 32 is replaced. 32 cleanings can be performed.

A plurality of valve body housing portions 82 are spaced apart in the circumferential direction of the rotation axis AX. Thereby, the valve replacement unit 80 having a plurality of valve bodies 32 can be installed in a limited space.

FIG. 12 shows a modification of cleaning area 114 . The modified cleaning area 114A is divided into a plurality of areas 124 along the track of the valve body 32 . In the modified example of FIG. 12, five regions 124-1 to 124-5 are provided corresponding to the five valve body housing portions 82 in which valve bodies 32 that are not in use are housed. The area 124 of the cleaning area 114A is not limited to the modified example of FIG. 12 as long as it is plural.

By providing a plurality of areas 124 in the cleaning area 114A, for example, the roughness of the brush or sponge may be changed for each area 124, or the cleaning area 124 and the non-cleaning area 124 may be provided. A separate cleaning area 114A may be provided.

The present invention is not limited to the above embodiments, and various additions, changes, or deletions are possible without departing from the scope of the present invention. For example, in the above embodiment, a pilot operated pressure reducing valve has been described, but the valve replacement mechanism of the present invention can also be applied to a direct acting pressure reducing valve that does not have a pilot valve. Further, in the valve replacement unit 80 of the above-described embodiment, the valve housing portion 82 is switched by rotating about the rotation axis AX, but by sliding in a direction orthogonal to the rotation axis AX, the valve housing portion 82 is switched. The part 82 may be switched. Accordingly, such are also included within the scope of this invention.

1 main passage 18 main valve body 24 main valve drive section (second valve drive section)
30 pilot valve unit 32 valve body 34 valve device 36 pilot valve driving section (first valve driving section)
37 valve seat block 40 valve seat 42 shaft member 44 first spring body 49 pressure adjusting means (valve closing force applying member)
54 Second spring body 62 Pilot chamber (inflow path)
68 through passage (outflow passage)
80 valve replacement unit 82 valve housing 84 valve switching mechanism 114, 114A cleaning area AX rotation axis PRV pressure reducing valve S steam (fluid)

Claims (3)

a valve body that opens and closes between the inflow path and the outflow path of the fluid;
a first spring body that causes the valve body to be seated on the valve seat by a spring force;
a shaft member that presses the valve body in a valve-opening direction to separate it from the valve seat;
a valve replacement unit that discharges the valve body in use and installs a new valve body at the use position;
The valve replacement unit includes: a plurality of valve body housing portions for housing the valve body; a valve body switching mechanism for switching between the plurality of valve body housing portions to move the valve body to the use position; and a cleaning area that contacts and cleans the valve body during movement. 2. The valve device according to claim 1, wherein the plurality of valve body housing portions are spaced apart in the circumferential direction of the rotation axis. A pressure reducing valve arranged in a main fluid passage to reduce the pressure on the primary side to the pressure on the secondary side,
a main valve body that opens and closes the main passage;
and a pilot valve unit that opens and closes the main valve body,
wherein the pilot valve unit is the valve device according to claim 1 or 2;
a first valve drive unit that presses the shaft member of the valve device in a valve opening direction to separate the valve body from the valve seat;
The first valve drive unit includes a second spring body that advances and presses the shaft member in the valve opening direction, and a spring force that receives the pressure from the secondary side and presses the second spring body. a valve-closing force applying member that retracts in the valve-closing direction against the
Furthermore, a second valve drive section is provided for receiving the pressure of the outflow passage and opening the main valve body,
A pressure reducing valve in which the inflow passage of the valve device communicates with the primary side of the main passage.

Images