JP2020029872A - Pressure reduction valve - Google Patents

Abstract

To provide a pressure reduction valve without size increase while reducing the risk of fluid leakage.SOLUTION: A pressure reduction valve 1 that reduces the pressure of primary pressure fluid flowing from external piping 75 to a secondary pressure, comprises: a seat piece 65 having a primary side passage 15 communicated with the external piping and a valve seat part 20 formed downstream of the primary passage; a valve body 3 that moves between a closed position seated on the valve seat part and an open position separated from the valve seat part; a casing 2 having a secondary side passage 41, and a valve body space 24 in which the valve body is arranged and which is formed between a primary side passage and a secondary side passage; and a secondary pressure seal member 63 provided between the casing and the seat piece.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a pressure reducing valve that reduces the pressure of a fluid having a primary pressure to a secondary pressure.

  Conventionally, a pressure reducing valve for reducing the pressure of a fluid having a primary pressure to a secondary pressure has been known. For example, the pressure reducing valve disclosed in Patent Literature 1 communicates with a primary chamber through which fluid flows in from a primary pipe through a communication hole, and allows the fluid to flow out to a secondary pipe. A casing having a secondary chamber (referred to as a housing body in Patent Document 1) is provided.

  The casing is connected to a fuel gas pipe through which a fluid of a primary pressure flows, and is provided with a primary port member forming a primary port. Although not shown in Patent Literature 1, it is considered that a seal member (high-pressure seal member) that suppresses leakage of the primary pressure fluid is provided between the primary port member and the casing. In addition, a seal member (low-pressure seal member) that suppresses leakage of secondary pressure fluid is provided between the casing and the cover.

JP 2010-244362 A

  However, in the casing of the conventional pressure reducing valve, there is a portion through which the primary pressure fluid passes, that is, a portion where the primary pressure fluid acts, so that the casing is required to have strength. However, from the viewpoint of reducing the material cost of the casing, it is difficult to produce a thin-walled casing using a high-strength and high-cost material. Therefore, the cost is reduced by increasing the thickness of the casing using a low-cost material. As a result, the entire pressure reducing valve tends to be large.

  Therefore, an object of the present invention is to provide a pressure reducing valve in which a fluid having a high primary pressure does not act on a casing and does not increase in size.

  The pressure reducing valve of the present invention is a pressure reducing valve that reduces the pressure of the primary pressure fluid flowing from the external pipe to a secondary pressure, and has a primary side passage communicating with the external pipe, and a downstream side of the primary side passage. A seat piece having a formed valve seat portion, a valve body moving between a closed position seated on the valve seat portion and an open position separated from the valve seat portion, a secondary-side passage, and the A casing formed between the primary side passage and the secondary side passage and having a valve body space in which the valve body is disposed, and a secondary pressure seal member provided between the casing and the seat piece. It is equipped.

  According to the present invention, the casing is not required to have high strength because the casing does not have a portion on which the fluid of the primary pressure acts. Accordingly, since it is not necessary to increase the thickness of the casing, the entire pressure reducing valve does not become large.

  In the above invention, the sheet piece has a piping connection portion formed on the upstream side of the primary side passage, and the primary pressure is reduced by connecting an external piping and the piping connection portion of the sheet piece. It is desirable that fluid leakage be prevented.

  According to the above configuration, the leakage of the primary pressure fluid is prevented without the need for the primary pressure sealing member (high pressure sealing member) at the pipe connection portion.

  In the above invention, the sheet piece includes a concave-shaped sheet main body in which the pipe connection portion connected to the external pipe is formed on an inner bottom portion, and the external pipe communicates with the primary side passage. A pipe portion provided with a pipe passage, and a tubular portion into which the seat body is inserted and screwed, wherein the sheet body is inserted into the tubular portion of the external pipe and screwed. In this state, the downstream end of the pipe section is desirably configured to be pressed by the pipe connection section of the sheet body.

  According to the above configuration, it is not necessary to provide a primary pressure seal member (high-pressure seal member) for suppressing leakage of the primary pressure fluid. This eliminates the risk of fluid leakage when using a high pressure seal member. Further, a metal seal is realized by the downstream end of the pipe portion being pressed by the pipe connection portion at the bottom of the seat body portion in a state where the seat body portion is inserted into the tubular portion of the external pipe and screwed together. I have. Furthermore, the number of parts can be reduced as compared with a mode in which a filter described later is provided.

  In the above invention, the pressure reducing valve may include a filter provided in the primary passage of the seat piece, and a connection passage whose upstream end forms a connection portion with the external pipe and whose downstream end communicates with the primary passage of the seat piece. And a primary pressure seal member provided between the seat piece and the inlet housing.

  According to the above configuration, the number of components is increased as compared with the above-described embodiment in which no filter is provided, and a primary pressure seal member (high pressure seal member) is required between the sheet piece and the inlet housing, but the filter is built in. Can be. Thereby, it is possible to cope with an external pipe having no filter.

  In the above invention, the inlet housing has a piping connection portion formed on the upstream side of the connection passage, and primary pressure fluid is connected by connecting an external piping to the piping connection portion of the inlet housing. It is desirable that the leakage of water be prevented.

  According to the above configuration, the leakage of the primary pressure fluid is prevented without the need for the primary pressure sealing member (high pressure sealing member) at the pipe connection portion.

  In the above invention, the inlet housing includes a concave inlet main body having an inner bottom formed with the pipe connection portion connected to the external pipe, and the external pipe communicates with the connection passage. A pipe portion provided with a passage, and a tubular portion into which the inlet main body portion is inserted and screwed are provided, and the inlet main body portion is inserted into the tubular portion of the external pipe and screwed. In this state, it is preferable that the downstream end of the piping is configured to be pressed by the piping connection of the inlet main body.

  According to the above configuration, a metal seal is realized by the downstream end of the pipe portion being pressed by the pipe connection portion of the inlet body portion in a state where the inlet body portion is inserted into the tubular portion of the external pipe and screwed. Have been.

  Advantageous Effects of Invention According to the present invention, it is possible to provide a pressure-reducing valve that does not act on a casing with high-pressure primary-pressure fluid and does not increase in size.

It is a sectional view showing the pressure reducing valve concerning a 1st embodiment of the present invention. It is a sectional view showing the pressure reducing valve concerning a 2nd embodiment of the present invention.

  Hereinafter, a pressure reducing valve according to an embodiment of the present invention will be described with reference to the drawings. The pressure reducing valve described below is only one embodiment of the present invention. Therefore, the present invention is not limited to the following embodiments, and additions, deletions, and changes can be made without departing from the spirit of the present invention.

(1st Embodiment)
The pressure reducing valve 1 according to the present embodiment is a valve device used when a fluid such as a high-pressure gas is reduced to a working pressure or an atmospheric pressure, for example, a supply passage connected to a gas supply source such as a high-pressure tank or the atmosphere. It is used by being interposed in a discharge channel or the like that leads to As shown in FIG. 1, the pressure reducing valve 1 includes a casing 2, a valve body 3, a tubular reinforcing body 4, a rolling bearing 5, a spring member 6, a cover 12, a holder 13, and a seat piece 65. It has. However, the fluid may be a liquid.

  The casing 2 has an insertion hole 14 and a secondary passage 41 formed therein. Further, a sheet piece 65 having a primary side passage 15 formed vertically along the axis L1 of the pressure reducing valve 1 is attached to the casing 2. explain in detail. The casing 2 is provided with a hole 50 formed around the axis L1. The hole 50 communicates with a valve body space 24 described later.

  The seat piece 65 has a joint portion 60 which is inserted into and joined to the hole portion 50 of the casing 2 and is formed so as to protrude upward from a later-described sheet main body portion 62, and a flange portion 66 extending in the horizontal direction and having a concave cross-section. (Recessed downward in FIG. 1). In other words, the sheet main body 62 is formed in a bottomed tubular shape, and has a tubular portion 67 and an inner bottom portion 67a. The primary side passage 15 is formed along the up-down direction around the axis L1 over the joint portion 60 and the seat body portion 62 of the sheet piece 65 having such a configuration. The opening at the upstream end of the primary side passage 15 constitutes a pipe connection (primary port) 16 to which the external pipe 75 is connected. Further, since the flange portion 66 is fixed to the casing 2 by the bolt 68, the sheet piece 65 is attached to the casing 2. The outer peripheral surface of the flange 66 and the outer peripheral surface of the casing 2 are substantially flush.

  The external pipe 75 has a pipe section 70 having a pipe passage 71 whose primary end (high pressure) fluid flows and a downstream end connected to the pipe connection section 16 of the sheet piece 65, and a concave cross-section holding the pipe section 70. And a holding portion 74. In other words, the holding portion 74 has a tubular portion 72 and a bottom portion 73 that holds the tubular portion 72. An insertion hole 73a is formed in the bottom portion 73 of the holding portion 74 around the axis L1, and the pipe portion 70 is inserted into the insertion hole 73a. Further, the tip of the pipe part 70 is formed in a hemispherical shape, and the downstream end of the pipe passage 71 communicates with the pipe connection part 16. The cylinder 67 of the seat body 62 is inserted into the cylinder 72 of the external pipe 75 and screwed. As described above, in a state where the tubular portion 67 of the sheet main body 62 is inserted into the tubular portion 72 of the external pipe 75 and screwed, the downstream end (tip) of the pipe portion 70 is attached to the inner bottom 67 a of the seat main body 62. The metal seal is realized by being pressed, and the pipe passage 71 and the primary side passage 15 are communicated with each other in a state where the metal seal is formed.

  A first seal member (secondary pressure seal member) 63 that suppresses leakage of secondary pressure fluid is provided between the casing 2 and the sheet piece 65. Specifically, a seal groove 64 is formed on the outer peripheral surface of the joining portion 60 of the sheet piece 65 over the entire circumference in the circumferential direction. A first seal member 63 such as an O-ring is fitted into the seal groove 64. The first seal member 63 seals between the joint 60 of the sheet piece 65 and the inner peripheral surface of the hole 50 of the casing 2. Thus, leakage of the fluid of the secondary pressure in the valve body space 24 to the outside is suppressed.

  The insertion hole 14 of the casing 2 is formed downward from an upper surface of a concave portion 11a described later, and has an opening 14a on the upper surface. The insertion hole 14 is a hole with a bottom, and a secondary side passage 41 is formed in a side wall portion that defines the insertion hole 14. The primary side passage 15 formed in the sheet piece 65 is connected to a pipe connection 16 into which a fluid flows. The secondary passage 41 is formed at a position radially outward from the primary passage 15 and extends in the horizontal direction. The secondary passage 41 is connected to a secondary port 42. An annular recess 11a is formed around the opening 14a of the casing 2. An annular stepped portion 11b which is located higher than the concave portion 11a is formed at a radially outer portion of the concave portion 11a. A cover 12 is provided on the stepped portion 11b so as to cover the opening 14a.

  The cover 12 is formed in a cylindrical shape with a bottom, and is opened on the lower side. The cover 12 is formed such that its inner diameter substantially matches the diameter of the recess 11 a of the casing 2. Further, a flange 12b is formed on the open end 12a of the cover 12 so as to extend radially outward over the entire circumference in the circumferential direction. The flange 12b is placed on the stepped portion 11b of the casing 2, and is fixed to the casing 2 by a fastening member such as a bolt (not shown). The cover 12 is provided on the casing 2 so as to cover the valve body 3 and a holder 13 described below.

  The holder 13 is formed in a cylindrical shape, and a tip portion 13a thereof is inserted into the insertion hole 14 and screwed. The holder 13 holds the valve body 3 so that the valve body 3 can slide along the axis L1. The holder 13 is provided with a flange 13b extending radially outward from the insertion hole 14 at an intermediate portion thereof and integrated with the holder 13. The flange 13b is formed such that its outer diameter substantially matches the diameter of the recess 11a of the casing 2, and a part of the flange 13b is fitted in the recess 11a. The upper portion of the flange 13b protrudes upward, and is fitted to the cover 12 such that the outer peripheral surface of the upper portion contacts the inner peripheral surface of the cover 12. The holder 13 has a through hole vertically penetrated with respect to the axis L1, and the valve body 3 is inserted into the through hole so as to be able to reciprocate up and down.

  The valve body 3 is made of a soft material such as an aluminum alloy and is formed in a column shape. The base 3a of the valve element 3 protrudes radially outward from the remaining portion constituting the valve element 3. The remaining portion of the valve element 3 is inserted into the holder 13, and the tip 3 b projects further downward from the tip 13 a of the holder 13. The valve body space 24 is formed around the valve body 3 and below the valve body 3 in a state where the holder 13 is inserted into the insertion hole 14 and the valve body 3 is inserted through the holder 13. The distal end portion 3b is disposed opposite to the downstream end of the primary side passage 15, and an annular valve seat portion 20 is formed around the downstream end. Further, the valve element 3 has a seat portion 21 at a portion of the distal end portion 3b facing the valve seat portion 20. The seat portion 21 of the valve body 3 moves between a closed position where the seat portion is seated on the valve seat portion 20 and an open position where the seat portion 21 is separated from the valve seat portion 20. When the seat portion 21 is in the open position, an orifice 22 is formed between the seat portion 21 and the valve seat portion 20, and high-pressure fluid from the primary passage 15 is depressurized by the orifice 22. .

  A tubular reinforcing body 4 called a bush is provided at an intermediate portion of the valve body 3. The tubular reinforcing member 4 is a thin-walled cylindrical member made of a material harder than the material of the valve body 3, for example, a chromium molybdenum steel material subjected to gas carburizing and quenching. The tubular reinforcing body 4 is fixed around the valve body 3 by press-fitting into an intermediate portion of the valve body 3. In addition, the method of packaging is not limited to press fitting. The intermediate portion of the valve body 3 is reinforced by the attachment of the tubular reinforcement 4, and is inserted into the holder 13 with the attachment of the tubular reinforcement 4. In the holder 13, a bearing housing space 25, which is a substantially cylindrical space, is formed around an intermediate portion of the valve body 3. In detail, the inner peripheral surface of the holder 13 has an inward flange 13c formed at the intermediate portion over the entire circumference in the circumferential direction, and the intermediate portion projects radially inward compared to the remaining portion. I have. Thereby, a bearing housing space 25 which is a substantially cylindrical space is formed between the holder 13 and the valve body 3 on the base end side of the holder 13, and the rolling bearing 5 is housed in the bearing housing space 25. ing.

  The rolling bearing 5 is a so-called linear motion type ball guide, and has a substantially cylindrical shape. The rolling bearing 5 is fitted and fixed to the inner peripheral portion of the holder 13 so as to be housed in the bearing housing space 25. The valve body 3 is inserted into the rolling bearing 5 with the cylindrical reinforcing body 4 interposed therebetween. That is, the rolling bearing 5 is provided on the tubular reinforcing member 4 attached to the intermediate portion of the valve body 3. As a result, the valve element 3 is supported by the rolling bearing 5 via the cylindrical reinforcing member 4, and can smoothly reciprocate in the vertical direction along the axis L1. Conventionally, the ball 5a of the rolling bearing 5 is brought into contact with the surface of the valve body 3 and the valve body 3 is directly supported by the rolling bearing 5, so that the surface of the base material of the valve body 3 made of a soft material is plated. The treatment is performed to achieve hardening. However, the base material of the valve body 3 may not be able to withstand the surface pressure received from the ball 5a of the rolling bearing 5, and may be dented, or the plating layer formed on the surface may be peeled off and the base material may be damaged. By interposing the cylindrical reinforcing member 4, the ball 5a of the rolling bearing 5 can be rolled on the outer surface of the cylindrical reinforcing member 4, and the surface pressure of the ball 5a is reduced by the cylindrical reinforcing member 4 made of a hard material. Can receive. Therefore, deformation of the base material of the valve body 3 can be suppressed, and the durability of the valve body 3 can be improved.

  As described above, the intermediate portion of the valve element 3 is supported by the rolling bearing 5 via the cylindrical reinforcing member 4 so as to be able to reciprocate. Further, in the valve body 3, a distal end portion 3 c, which is a portion (excluding the distal end portion 3 b) closer to the distal end than the tubular reinforcing body 4, is inserted into a hole formed by the inward flange 13 c of the holder 13. . A seal groove 26 is formed on the outer peripheral surface of the distal end portion 3c of the valve element 3 over the entire circumference in the circumferential direction.

  A valve body seal 27 such as an O-ring is fitted into the seal groove 26. The valve body seal 27 is in contact with the inward flange 13c to seal between the distal end portion 3c and the inward flange 13c. Thus, the distal end portion 3c of the valve element 3 is inserted into the inward flange 13c in a sealed state, and is guided by the inward flange 13c so as to move along the axis L1.

  A base 3 a of the valve body 3, which is a portion closer to the base end than the tubular reinforcing body 4, protrudes outward from the holder 13, and its outer diameter is substantially equal to the inner diameter of the cover 12. Therefore, the outer peripheral surface of the base 3a faces the inner peripheral surface of the cover 12, and the seal groove 28 is formed on the outer peripheral surface of the base 3a over the entire circumference in the circumferential direction. A seal 29 for a valve body such as an O-ring is fitted in the seal groove 28, and the seal 29 for the valve body is in contact with the inner peripheral surface of the cover 12 and between the base 3 a of the valve body 3 and the cover 12. Is sealed. Thus, the base 3a of the valve body 3 is fitted into the inner peripheral surface of the cover 12 in a sealed state, and is guided by the cover 12 so as to reciprocate along the axis L1.

  The base 3a of the valve body 3 has a spring receiving portion 3d. The spring receiving portion 3d is formed on the outer peripheral edge of the lower surface of the base 3a, and is arranged to face the upper surface of the flange 13b of the holder 13. A cylindrical spring accommodating space 30 surrounded by the holder 13 and the cover 12 is formed between the spring receiving portion 3d and the flange 13b, and the spring member 6 is accommodated in the spring accommodating space 30. . The spring member 6 is, for example, a compression coil spring. Each of an upper end and a lower end of the spring member 6 is supported by a spring receiving portion 3d of the base 3a and a spring receiving portion 13d which is an upper surface of the holder 13. The spring member 6 is housed in a compressed state in the spring housing space 30 and urges the valve body 3 toward the open position. Further, a secondary pressure acting on the valve element 3 against the urging force of the spring member 6 (that is, moving the valve element 3 toward the closed position) acts on the valve element 3. A recess 31 is formed in the base 3a of the valve body 3 for receiving pressure.

  The recess 31 is formed in the base 3a of the valve body 3 and extends along the axis L1. The recess 31 is opened toward the ceiling portion 12c of the cover 12, and a secondary pressure chamber 32 including the recess 31 is formed between the base 3a of the valve body 3 and the ceiling portion 12c of the cover 12. Have been. The secondary pressure chamber 32 is isolated from the spring housing space 30 by the valve body seal 29 and is connected to the valve body space 24 via the communication hole 33 of the valve body 3.

  The communication hole 33 includes a communication portion 33a and a connection portion 33b. The communication portion 33a extends from the bottom defining the recess 31 toward the distal end 3b of the valve body 3 along the axis L1. The distal end of the communication portion 33a extends to a position short of the distal end portion 3b, and is connected to the connection portion 33b. The connection part 33b extends so as to penetrate the valve body 3 in the radial direction. The portion of the valve element 3 closer to the distal end portion 3b than the distal end portion 3c is formed to have a smaller diameter than the distal end portion 3c. In such a configuration, the valve body space 24 communicates with the secondary pressure chamber 32 through the communication hole 33, and the working gas guided to the valve body space 24 is guided to the secondary pressure chamber 32 through the communication hole 33. I will

  The base end of the valve body 3 forms a pressure receiving surface 3e that receives the pressure of the fluid (ie, the secondary pressure) guided to the secondary pressure chamber 32, and the valve body 3 is closed by the fluid of the secondary pressure. Pushed toward position. In this way, the valve element 3 receives the secondary pressure fluid guided to the secondary pressure chamber 32 on the pressure receiving surface 3e, and applies a force to the valve element 3 so that the urging force of the spring member 6 and the secondary pressure oppose each other. To work.

  In such a pressure reducing valve 1, the spring housing space 30 is isolated from the valve body space 24 by the valve body seal 27, and is isolated from the secondary pressure chamber 32 by the valve body seal 29. Therefore, when the valve element 3 moves, the gas (that is, air) in the spring accommodating space 30 expands and contracts, and the air communication hole 35 is formed in the cover 12 in order to prevent the expansion and contraction. The atmosphere communication hole 35 opens the spring accommodating space 30 to the atmosphere, and discharges the air in the spring accommodating space 30 to the atmosphere and sucks air from the atmosphere into the spring accommodating space 30. A cap member 36 is fitted and fixed to the atmosphere communication hole 35. The cap member 36 allows passage of gas such as air while preventing passage of liquid such as rain. Accordingly, it is possible to prevent liquid such as rain from entering the spring accommodating space 30.

  The casing 2 is provided with a gas seal 37 and a waterproof seal 38. The gas seal 37 is for suppressing the fluid from flowing out to the cover 12, the atmosphere, or the like. The gas seal 37 is formed of, for example, an O-ring made of synthetic rubber or the like, and is provided on the distal end portion 13 a of the holder 13. Specifically, the gas seal 37 is provided on the distal end portion 13a in a state of being in contact with the lower surface of the flange 13b of the holder 13. The gas seal 37 can isolate the valve body space 24 from the spring housing space 30 and the atmosphere, and suppresses the fluid in the valve body space 24 from flowing into the spring housing space 30 and the atmosphere. The waterproof seal 38 is for preventing liquid such as rain from entering the pressure reducing valve 1, and is formed of, for example, an O-ring made of synthetic rubber. The casing 2 is provided with a seal accommodation space 39 for disposing the waterproof seal 38.

  Subsequently, the operation of the pressure reducing valve 1 of the present embodiment will be described. Hereinafter, an operation when the fluid guided from the external pipe 75 to the pipe connecting portion 16 is depressurized will be described with reference to FIG. The pressure reducing valve 1 is normally open because the valve body 3 is urged in the opening direction by the spring member 6, and the fluid (the fluid of the high-pressure primary pressure, which is a high-pressure primary pressure) guided to the pipe connection portion 16. ) Is led to the valve body space 24 through the orifice 22. The fluid is reduced in pressure from the primary pressure to a low secondary pressure when passing through the orifice 22, is guided to the valve body space 24, and is supplied to downstream devices through the secondary passage 41 and the secondary port 42. It has become.

  The reduced pressure (secondary pressure) fluid is guided not only to the secondary side passage 41 but also to the secondary pressure chamber 32 through the communication hole 33 of the valve body 3. Thereby, the fluid of the secondary pressure acts on the pressure receiving surface 3e of the valve body 3, and the valve body 3 is pushed toward the closed position by the fluid of the secondary pressure. As a result, the valve element 3 moves in the direction in which the orifice 22 is closed, and the position where the acting force of the secondary pressure received by the pressure receiving surface 3e, the urging force of the spring member 6, and other forces acting on the valve element 3 are balanced. Move up to. For example, when the secondary pressure decreases, the acting force acting on the pressure receiving surface 3e decreases, and the urging force of the spring member 6 exceeds the acting force acting on the pressure receiving surface 3e. Then, the valve element 3 moves toward the open position to open the orifice 22 so as to maintain a balance between the acting force acting on the pressure receiving surface 3 e and the urging force of the spring member 6. Thereby, the secondary pressure increases and is maintained at the set pressure.

  As described above, according to the pressure reducing valve 1 of the present embodiment, the casing 2 is configured such that the portion where the high-pressure fluid that is the primary pressure acts does not exist in the casing 2, and thus the casing 2 does not require high strength. Therefore, since it is not necessary to increase the thickness of the casing 2, the entire pressure reducing valve 1 does not increase in size. Further, in the pressure reducing valve 1, a seal member (high-pressure seal member) for suppressing leakage of the primary pressure fluid does not need to be provided. This eliminates the risk of fluid leakage when using a high pressure seal member. Furthermore, the number of components can be reduced as compared with a mode in which a filter according to a second embodiment described later is provided.

(2nd Embodiment)
Next, a pressure reducing valve 1a according to a second embodiment of the present invention will be described with reference to the drawings. In the second embodiment, the same components as those in the above-described first embodiment are denoted by the same reference numerals, and a description thereof will be omitted unless otherwise described.

  As shown in FIG. 2, in the pressure reducing valve 1 a according to the second embodiment, the seat piece 65 a is formed in a substantially cylindrical shape below the joint 60 and the joint 60 similar to the first embodiment. And a seat body 62a. The seat piece 65a is provided with primary side passages 15a, 15b, 15c formed along the up-down direction about the axis L1 of the pressure reducing valve 1a. An upstream end of the primary passage 15a is connected to a primary passage 15b formed in the sheet main body 62a and having a larger diameter toward the upstream side. Further, a primary passage 15c formed in the seat body 62a and having a diameter larger than that of the primary passage 15a is connected to an upstream end of the primary passage 15b. Thus, the primary passage 15a communicates with the primary passage 15c via the primary passage 15b. A filter 81 that prevents iron powder and the like generated when attaching and detaching the component articles from flowing into the downstream side is fitted and provided in an upper portion of the primary side passage 15c.

  In the present embodiment, an inlet housing 90 is attached to the sheet piece 65a. In detail, the inlet housing 90 has an inlet body 95 formed with a connection passage 92 having a downstream end communicating with the primary passage 15c and an upstream end communicating with the pipe passage 71 of the external pipe 75. It has a tubular portion 91 provided at an upper portion of the main body portion 95 and a tubular portion 94 provided at a lower portion of the inlet main body portion 95 and defining an inner bottom portion 94a.

  The opening at the upstream end of the connection passage 92 constitutes a pipe connection (primary port) 93 to which the external pipe 75 is connected. The downstream end of the pipe passage 71 communicates with a pipe connection portion 93. The seat body 62a is inserted into and screwed into the tube 91 of the inlet housing 90, and the tube 94 of the inlet housing 90 is inserted into and screwed into the tube 72 of the external pipe 75. In this manner, with the tubular portion 94 of the inlet housing 90 inserted and screwed into the tubular portion 72 of the external pipe 75, the downstream end (tip) of the pipe section 70 is pressed against the inner bottom 94a of the inlet main body 95. As a result, a metal seal is realized, and the pipe passage 71 and the connection passage 92 are communicated with each other in a state where the metal seal is completed.

  Between the seat piece 65a and the inlet housing 90, there is provided a second seal member 69 for suppressing leakage of primary pressure fluid. Specifically, a concave annular seal groove 80 is formed inside on the outer peripheral surface (that is, the lower surface) perpendicular to the axis L1 of the seat body 62a. A second seal member 69 such as an O-ring is fitted in the seal groove 80. The second seal member 69 seals the space between the seat body 62a and the inlet body 95. Accordingly, leakage of the primary pressure fluid to the outside is suppressed.

  As described above, according to the pressure reducing valve 1a of the second embodiment, as in the first embodiment, a portion where the fluid of the primary pressure acts does not exist in the casing 2, so that the casing 2 has high strength. Is not required. Therefore, since it is not necessary to increase the thickness of the casing 2, the entire pressure reducing valve 1a does not become large due to the increase in the casing 2. Also, although the number of components is increased and the second seal member 69 is required between the sheet piece 65a and the inlet housing 90 as compared with the above-described first embodiment in which the filter 81 is not provided, the filter 81 may be built in. it can. Thereby, it is possible to cope with the external pipe 75 having no filter.

(Other embodiments)
The present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist of the present invention. For example:

  In the first and second embodiments, an O-ring may be provided around the downstream end of the pipe passage 71 at the tip of the pipe portion 70 of the external pipe 75. Thereby, the reliability of the sealing between the pipe passage 71 and the connection passage 92 can be further improved.

  In the first and second embodiments, the joining portion 60 of the sheet piece 65 is inserted into the hole 50 formed in the casing 2 and joined. However, the present invention is not limited to this. You may comprise so that it may be inserted in the hole 50 and screwed. In this case, a first seal member can be provided between the lower surface of the casing 2 and the upper surface of the seat body 62.

  Further, in the first and second embodiments, the holder 13 is provided with the flange 13b, but the flange 13b may be omitted. In this case, the outer peripheral surface of the holder 13 is fitted to the inner peripheral surface of the cover 12, and the spring member 6 can be provided between the upper end of the holder 13 and the portion of the valve body 3 arranged opposite to the upper end. . Thereby, the diameter of the cover 12 can be reduced.

1, 1a Pressure reducing valve 2 Casing 3 Valve body 15, 15a, 15b, 15c Primary passage 16 Piping connection 20 Valve seat 24 Valve body space 41 Secondary passage 62, 62a Seat body 63 First seal member ( Secondary pressure seal member)
65, 65a Sheet piece 67a Inner bottom 69 Second seal member (primary pressure seal member)
REFERENCE SIGNS LIST 70 piping part 71 piping passage 72 cylinder part 73 bottom part 74 holding part 75 external piping 81 filter 90 inlet housing 92 connection passage 93 piping connection part 94 a inner bottom part 95 inlet body part

Claims (6)

A pressure reducing valve for reducing the pressure of a primary pressure fluid flowing from an external pipe to a secondary pressure,
A seat piece having a primary passage communicating with the external pipe, and a valve seat portion formed downstream of the primary passage,
A valve body that moves between a closed position seated on the valve seat portion and an open position separated from the valve seat portion;
A secondary side passage, and a casing having a valve body space formed between the primary side passage and the secondary side passage and in which the valve body is disposed,
A pressure reducing valve comprising a secondary pressure seal member provided between the casing and the sheet piece. The sheet piece has a pipe connection portion formed on the upstream side of the primary passage,
The pressure reducing valve according to claim 1, wherein leakage of a primary pressure fluid is prevented by connecting an external pipe to the pipe connection portion of the sheet piece. The sheet piece includes a concave sheet body in which the pipe connection portion connected to the external pipe is formed on an inner bottom portion,
The external piping includes a piping portion provided with a piping passage communicating with the primary-side passage, and a tubular portion into which the seat body is inserted and screwed,
In a state where the sheet main body is inserted into the tubular portion of the external pipe and screwed, the downstream end of the pipe is configured to be pressed by the pipe connection portion of the seat main body. The pressure reducing valve according to claim 2. A filter provided in the primary passage of the sheet piece,
An inlet housing having a connection passage whose upstream end constitutes a connection portion with the external pipe and whose downstream end communicates with the primary passage of the sheet piece;
The pressure reducing valve according to claim 1, further comprising a primary pressure sealing member provided between the seat piece and the inlet housing. The inlet housing has a pipe connection portion formed upstream of the connection passage,
The pressure reducing valve according to claim 4, wherein leakage of a primary pressure fluid is prevented by connecting an external pipe and the pipe connection portion of the inlet housing. The inlet housing includes a concave inlet main body formed with the piping connection portion connected to the external piping at an inner bottom portion,
The external pipe includes a pipe portion provided with a pipe passage communicating with the connection passage, and a tubular portion into which the inlet main body is inserted and screwed,
In a state where the inlet main body is inserted into the tubular part of the external pipe and screwed, the downstream end of the pipe is configured to be pressed by the pipe connection part of the inlet main body. A pressure reducing valve according to claim 5.

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