JP2014013456A - Pressure reduction valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure reduction valve capable of holding a seal member in a seal housing with a simple structure without using press-fitting means causing the generation of a chip.SOLUTION: In a pressure reduction valve, a back pressure chamber 35 is disposed so as to be faced by the back face of a valve body 10 for pressure reduction on the opposite side to a valve seat member 26, and to communicate with a pressure reduction chamber 18 between the vale body 10 and a valve body guide member 28, and a cylindrical seal housing 100 faced by the outer peripheral surface of the valve body 10 for pressure reduction is formed at the valve body guide member 28, and a seal member 32 formed so as to be slidable in close contact with the outer peripheral surface of the valve body 10 for pressure reduction for sealing a gap between a high pressure chamber 31 and the back pressure chamber 35 is mounted on the seal housing 100. A synthetic resin seal holding member 34 for closing the opening of the seal housing 100 while surrounding the valve body 10 for pressure reduction relatively movably in an axial direction, and for blocking the departure of the seal member 32 from the seal housing 100 is held between the valve seat member 26 and the valve body guide member 28.

Description

  The present invention provides a valve seat member having a valve hole communicating between the high pressure chamber and the decompression chamber, a cylindrical valve body guide member connected to the valve seat member, and a slidably supported by the valve body guide member. A pressure reducing valve body that opens and closes the valve hole in cooperation with the valve seat member, and a control pressure chamber connected to a valve shaft connected to the pressure reducing valve body so as to pass through the valve hole. And a passive member disposed so as to partition the pressure acting chamber, and a back surface of the valve body opposite to the valve seat member faces between the pressure reducing valve body and the valve body guide member. A back pressure chamber communicating with the decompression chamber is provided, and a cylindrical seal housing is formed on the valve body guide member so that an outer peripheral surface of the decompression valve body faces, and an outer periphery of the decompression valve body is formed on the seal housing. Equipped with a seal member that seals between the high pressure chamber and the back pressure chamber in close contact with the surface. It was related to improvement of the pressure reducing valve.

  Such a pressure reducing valve is already known as disclosed in Patent Document 1 below.

JP 2010-237863 A

  In such a conventional pressure reducing valve, a metal ring for closing the opening of the seal housing is press-fitted into the valve body guide member in order to hold the seal member in the seal housing.

  However, as described above, when a metal ring is press-fitted and attached to the valve body guide member, chips may be generated during the press-fitting, and the chips adhere to the valve seat member and the pressure-reducing valve body. As a result, the proper closing of the pressure reducing valve element may be impaired.

  The present invention has been made in view of such circumstances, and provides the pressure reducing valve that can hold the seal member in the seal housing with a simple structure without using press-fitting means that causes chips. Objective.

  In order to achieve the above object, the present invention provides a valve seat member having a valve hole communicating between a high pressure chamber and a decompression chamber, a cylindrical valve body guide member connected to the valve seat member, and the valve body. A pressure reducing valve body that is slidably supported by the guide member and cooperates with the valve seat member to open and close the valve hole, and a valve that is connected to the pressure reducing valve body so as to penetrate the valve hole A passive member connected to a shaft and arranged to partition between the control pressure chamber and the pressure action chamber, and between the pressure reducing valve body and the valve body guide member, the valve seat member of the valve body, Is provided with a back pressure chamber that faces the back surface on the opposite side and communicates with the decompression chamber, and the valve body guide member is formed with a cylindrical seal housing that faces the outer peripheral surface of the pressure reducing valve body. , Slidably in close contact with the outer peripheral surface of the pressure reducing valve body, and between the high pressure chamber and the back pressure chamber. In a pressure reducing valve equipped with a sealing member to be sealed, the opening for the seal housing is closed to surround the pressure reducing valve body so as to be axially movable relative to each other, thereby preventing the seal member from being detached from the seal housing. A first feature is that a resin seal holding member is sandwiched between the valve seat member and the valve element guide member. The high-pressure chamber, the passive member, and the seal member respectively correspond to a valve chamber 31, a diaphragm 8, and a fifth seal member 32 in an embodiment of the present invention described later.

  According to the present invention, in addition to the first feature, the end face of the seal holding member receives the clamping force of the valve seat member and the valve body guide member, and faces the end face of the valve seat member or the valve body guide. A second feature is that a plurality of protrusions that are compressed and deformed by the end face of the member are integrally formed.

  Furthermore, in addition to the first or the second feature, the present invention provides an annular shoulder portion that is formed on the outer periphery of the pressure reducing valve body and faces the inner end surface of the seal holding member on the side opposite to the seal member. The third feature is that the valve seat member and the valve body guide member are connected to each other by press-fitting to constitute a pressure reducing valve assembly.

  According to the first aspect of the present invention, a synthetic resin seal that closes the opening of the seal housing and surrounds the pressure-reducing valve body so as to be movable in the axial direction and prevents the seal member from being detached from the seal housing. By holding the holding member between the valve seat member and the valve element guide member, the seal holding member can be easily attached to the housing using the valve seat member. In addition, since the seal holding member is made of synthetic resin, there is no fear of generation of chips.

  According to the second feature of the present invention, the end face of the seal holding member receives the clamping force of the valve seat member and the valve body guide member, and is compressed and deformed by the end face of the valve seat member or the valve body guide member facing the end face. By integrally forming the plurality of projections, the dimensional error in the axial direction of the seal holding member itself can be absorbed by the compression deformation of the projection, and the seal holding member is attached to the valve body guide member without play. be able to.

  According to the third feature of the present invention, an annular shoulder portion is formed on the outer periphery of the pressure-reducing valve body so as to face the inner end surface of the seal holding member opposite to the seal member. Since the pressure-reducing valve assembly is configured by connecting the valve body guide members together by press-fitting, the components of the pressure-reducing valve are prevented from being disassembled, and the handling of the pressure-reducing valve is facilitated. It can contribute to the improvement of sex.

The 1st Embodiment of the present invention is the longitudinal section of the decompression device in the state where the decompression valve opened and the shut-off valve closed. FIG. 2 is an enlarged view of a portion indicated by an arrow 2 in FIG. 1. FIG. 3 is a perspective view of a seal holding member in FIG. 2. FIG. 3 is a view corresponding to FIG. 2 showing a second embodiment of the present invention.

  First, a first embodiment of the present invention will be described with reference to FIGS.

  First, in FIG. 1, this decompression device is mounted in an engine room of a gas fuel vehicle for decompressing high-pressure natural gas fuel and supplying it to an engine (not shown). A pressure reducing valve 6 having a pressure reducing valve body 10 connected to a diaphragm 8 which is a passive member, and a cutoff valve 7 having a cutoff valve body 78 driven by a solenoid 9 are arranged.

  The body 5 is formed by connecting a first body member 12 and a second body member 13 disposed above the first body member 12 to each other. The first body member 12 includes an outer cylinder portion 12a extending vertically, a first inward flange portion 12b projecting radially inward from a lower portion of the outer cylinder portion 12a, and a first body member 12 coaxially with the outer cylinder portion 12a. An inner cylindrical portion 12c extending upward from an intermediate portion of one inward flange portion 12b, and a short cylindrical portion 12d extending coaxially with the inner cylindrical portion 12c and slightly upward from the inner periphery of the first inward flange portion 12b. A sliding support hole 14 having a circular cross section coaxial with the outer cylinder portion 12a and the inner cylinder portion 12c is provided in the central portion of the first inward flange portion 12b and the short cylinder portion 12d. Is formed.

  The second body member 13 integrally has a fitting cylinder portion 13a fitted to the end portion of the inner cylinder portion 12c on the second body member 13 side, and a part of the fitting cylinder portion 13a is included in the fitting cylinder portion 13a. The formed accommodation hole 15 is provided in the second body member 13. The second body member 13 is integrally provided with a second inward flange 13b that protrudes radially inward from the end of the accommodating hole 15 on the diaphragm 8 side, that is, from the tip of the fitting tube 13a. Moreover, the accommodation hole 15 includes a screw hole portion 15a opened to the opposite side to the diaphragm 8, and a fitting hole portion 15b having a smaller diameter than the screw hole portion 15a and disposed on the second inward flange portion 13b side. Are connected to the same axis.

  An annular first seal member 16 is interposed between the outer cylinder portion 12 a of the first body member 12 and the second body 5, and the second body member 13 fitted into the inner cylinder portion 12 c of the first body member 12. An annular second seal member 17 is interposed between the fitting cylinder portion 13a and the inner cylinder portion 12c. Thus, a decompression chamber 18 is formed between the first and second body members 12 and 13 so that the outer periphery is defined by the inner cylindrical portion 12 c of the first body member 12. A communicating outlet passage 19 is connected to a connecting pipe 20 protruding from the side surface of the first body member 12. An annular passage 21 having an outer periphery and an inner periphery defined by the outer cylinder portion 12a and the inner cylinder portion 12c of the first body member 12 is formed between the first and second body members 12 and 13, and the decompression chamber 18 A heating medium such as hot water for heating the inside flows through the annular passage 21.

  Referring also to FIG. 2, the pressure reducing valve 6 is formed in a ring shape with a pressure reducing valve seat 25 that opens a valve hole 24 communicating with the pressure reducing chamber 18 at the center thereof and is formed in a ring shape. A valve seat member 26 fixedly disposed in the fitting hole portion 15b of the housing hole 15, a valve shaft 27 loosely passing through the inside of the second inward flange portion 13b and the valve hole 24, and the pressure reducing valve seat 25 and a pressure reducing valve body 10 that can be seated on the valve shaft 27 and connected to the valve shaft 27. The pressure reducing valve body 10 includes a core shaft 10a that is integrally connected to the valve shaft 27, and a synthetic resin valve cylinder 10b that is integrally fitted to the core shaft 10a.

  In the fitting hole portion 15b of the receiving hole 15, a dish-like holding portion 28a opened toward the second inward flange portion 13b side, and the second inner side are coaxially connected to the central portion of the holding portion 28a. A large-diameter cylindrical portion 28b extending on the opposite side of the facing flange portion 13b, a small-diameter cylindrical portion 28c formed smaller in diameter than the large-diameter cylindrical portion 28b and coaxially connected to the large-diameter cylindrical portion 28b, and the small-diameter cylindrical portion 28c 2 A valve body guide member 28 integrally having an end wall portion 28d that closes an end opposite to the inward flange 13b is inserted and fixed, and the valve seat member 26 includes the valve body guide member It is press-fitted and fixed to the 28 holding portions 28a. Thus, an annular third seal member 29 that is coaxial with the valve hole 24 is attached to the surface of the valve seat member 26 that faces the second inward flange 13b. An annular fourth seal member 30 that is coaxial with the third seal member 29 is mounted on the surface facing the body guide member 28.

  A valve chamber 31 for accommodating the pressure reducing valve body 10 is formed in the valve body guide member 28, and the pressure reducing valve seat 25 faces the inner periphery of the valve seat member 26 so as to face the valve chamber 31. The seating surface 10c seated on the pressure reducing valve seat 25 of the pressure reducing valve body 10 is also formed in a tapered shape.

  The pressure-reducing valve body 10 is slidably supported by a small-diameter cylindrical portion 28c of the valve-body guide member 28, and a valve opening position where the seating surface 10c is separated upward from the pressure-reducing valve seat 25 (FIG. 2). The state shown by a solid line) and the valve closing position (the state shown by the chain line in FIG. 2) where the seating surface 10c is seated on the pressure reducing valve seat 25 are movable. A back pressure chamber 35 is formed between the small diameter cylindrical portion 28c and the end wall portion 28d of the valve body guide member 28 and the valve shaft 27 and the pressure reducing valve body 10. The pressure reducing chamber 18 communicates with a communication path 36 provided in the shaft 27.

  An inner portion of the large-diameter cylindrical portion 28b is formed in a cylindrical seal housing 100 where the outer peripheral surface of the pressure reducing valve body 10 faces. The seal housing 100 is closed at the upper end on the small diameter cylindrical portion 28c side and is open at the lower end. The seal housing 100 includes a backup ring member 33 that surrounds the pressure reducing valve body 10 from the closed end portion 28d side, and is supported on the outer peripheral surface of the pressure reducing valve body 10 (in the illustrated example, the outer peripheral surface of the valve cylinder 10b). A fifth seal member 32 that is slidably in close contact with the valve chamber 31 and the back pressure chamber 35 is accommodated. The fifth seal member 32 is made of a synthetic resin that prevents the fifth seal member 32 from being detached from the seal housing 100. The seal holding member 34 is sandwiched between the valve element guide member 28 and the valve seat member 26. The fifth seal member 32 blocks communication between the valve chamber 31 and the back pressure chamber 35.

  2 and 3, the seal holding member 34 includes an annular first end plate 34a and an annular second end plate 34b having an inner diameter substantially the same as the outer diameter of the first end plate 34a. And a plurality of pillars 34c that stand up from the inner end surface of the second end plate 34b on the first end plate 34a side and are coupled to the outer peripheral surface of the first end plate 34a. Are integrally molded. At that time, a plurality of protrusions 34d are integrally projected on the outer end surface of the second end plate 34b. The seal holding member 34 having such a configuration can be formed with a pair of molds that can be opened and closed along the axial direction thereof.

  On the other hand, an annular positioning recess 101 having a larger diameter and adjacent to the open end of the seal housing 100 is formed on the inner periphery of the large diameter cylindrical portion 28b. The first end plate 34a is a pressure reducing valve. The outer periphery of the body 10 is fitted into a flange positioning recess 101 that surrounds the outer periphery of the body 10, and the second end plate 34 b is arranged with the outer end surface having a plurality of projections 34 d... Facing the valve seat member 26. The The seal holding member 34 is sandwiched between the valve body guide member 28 and the valve seat member 26 when the valve seat member 26 is press-fitted and fixed to the holding portion 28a of the valve body guide member 28, and the second end plate 34b. The plurality of protrusions 34d are compressed and deformed by receiving the clamping force.

  As described above, the synthetic resin seal holding member 34 holding the fifth seal member 32 in the seal housing 100 is sandwiched between the valve element guide member 28 and the valve seat member 26, so that the valve seat member 26 is used. Thus, the seal holding member 34 can be easily attached to the valve element guide member 28. In addition, since the seal holding member 34 is made of synthetic resin, there is no fear of generation of chips. Further, when the seal holding member 34 is sandwiched between the valve element guide member 28 and the valve seat member 26, the plurality of protrusions 34d... On the outer end surface of the second end plate 34b are compressed and deformed. It is possible to absorb an axial dimensional error of 34 itself, and to attach the seal holding member 34 to the valve element guide member 28 without play.

  An annular shoulder portion 10d that abuts against the inner end surface of the first end plate 34a is formed on the outer periphery of the pressure reducing valve body 10. In this way, the pressure reducing valve body 10 and the seal holding member 34 are axially connected to each other, and the valve body guide member 28 and the valve seat member 26 are connected to each other by the press-fitting, whereby the assembly of the pressure reducing valve 6 is achieved. Composed.

  In assembling the pressure reducing valve 6, first, the first end plate 34 a, the fifth seal member 32, and the backup ring 33 of the seal holding member 34 are sequentially fitted on the outer periphery of the pressure reducing valve body 10, thereby The plate 34 a is brought into contact with the annular shoulder 10 d of the pressure reducing valve body 10, and the upper end portion of the pressure reducing valve body 10 is protruded above the backup ring 33. Next, after the upper end portion of the pressure reducing valve body 10 is fitted into the small diameter cylindrical portion 28 c of the valve body guide member 28, the valve seat member 26 is press-fitted into the holding portion 28 a of the valve body guide member 28 and fixed. By assembling the valve assembly of the pressure reducing valve 6 in this way, it is possible to prevent the components from being disassembled, and the handling thereof is facilitated, which can contribute to the improvement of the assembly of the pressure reducing device.

  The sliding support hole 14 formed in the short cylindrical portion 12 d at the center of the first body member 12 has an annular sixth seal member 37 that elastically slides on the inner periphery of the sliding support hole 14. The diaphragm rod 38 having the outer periphery is fitted so as to be slidable.

  The diaphragm rod 38 is coaxially provided with a bottomed connection hole 40 opened to the pressure reducing valve body 10 side. The connecting hole 40 includes a bottomed cylindrical spring seat hole 40a, a spring guide hole 40b whose diameter increases from the outer end of the spring seat hole 40a toward the outside, and an outside of the spring guide hole 40b. A fitting hole 40c that is coaxially connected to the end, and a ring guide hole 40d that expands in a tapered shape outward from the outer end of the fitting hole 40c and opens at the front end surface of the diaphragm rod 38. .

  On the other hand, at the end of the valve shaft 27 passing through the valve hole 24 and extending toward the diaphragm rod 38, a reduced diameter shaft portion 27a and a diameter larger than the reduced diameter shaft portion 27a are arranged on both sides in the axial direction. The first and second enlarged diameter shaft portions 27b and 27c are provided. The first enlarged diameter shaft portion 27b is disposed on the pressure reducing valve body 10 side, and the second expanded diameter shaft portion 27c is disposed on the diaphragm rod 38 side. Is done.

  A holding plate 41 is attached to the reduced diameter shaft portion 27a. The holding plate 41 has a locking recess 41a that opens to one side and is formed in a U-shaped cross section. The locking recess 41a is larger than the outer diameter of the reduced diameter shaft portion 27a. In addition, the holding plate 41 has a width smaller than the outer diameters of the both diameter-expanded shaft portions 27b and 27c. It is attached to the portion 27a so as not to be relatively movable in the axial direction, and is slidably fitted into the fitting hole 40c of the diaphragm rod 38.

  An arc-shaped first locking groove 42 is provided on the outer periphery of the holding plate 41, and an annular second locking groove provided in correspondence with the first locking groove 42 on the inner periphery of the fitting hole 40c. 43, and a locking ring 44 that allows expansion and contraction along the radial direction of the valve shaft 27 is engaged with the first and second locking grooves 42, 43. The locking ring 44 is a substantially C-shaped elastic ring having one joint.

  Between the bottom surface of the spring seat hole 40a of the diaphragm rod 38 and the holding plate 41, a set spring 58 for biasing the holding plate 41 toward the valve opening side of the pressure reducing valve body 10 is contracted. As a result, the inner surface on the set spring 58 side of the first locking groove 42 and the inner surface of the locking ring 44 and the second locking groove 43 on the pressure reducing valve body 10 side are brought into contact with each other. Retained.

  One end face of the second enlarged diameter shaft portion 27c and the holding plate 41 facing each other in the axial direction is formed as a convex spherical surface 59, and the other end face is formed as a concave tapered surface 60. The surfaces 60 can come into contact with each other so as to be able to swing. In the illustrated example, a spherical surface 59 is provided on the second enlarged diameter shaft portion 27c side, and a tapered surface 60 is provided on the holding plate 41 side.

  Thus, the connecting hole 40, the reduced diameter shaft portion 27a, the first and second diameter expanded shaft portions 27b and 27c, the holding plate 41, the locking ring 44, the first and second locking grooves 42 and 43, and the set. The spring 58 constitutes a connection mechanism 39 that connects the diaphragm rod 38 and the valve shaft 27 in the axial direction.

  In assembling the coupling mechanism 39, first, the set spring 58 is dropped into the coupling hole 40 of the diaphragm rod 38. Then, one end of the set spring 58 is guided to the spring guide hole 40b and automatically received and positioned in the spring seat hole 40a, so that the set spring 58 can be automatically installed at a predetermined position. Next, the locking recess 41 a of the holding plate 41 is engaged with the reduced diameter shaft portion 27 a of the valve shaft 27 from the side, and the locking ring 44 is mounted in the first locking groove 42 of the holding plate 41. At this time, the locking ring 44 is in a free state in which the outer peripheral side protrudes a lot from the first locking groove 42. Subsequently, when the holding plate 41 is fitted together with the valve shaft 27 into the fitting hole 40c of the diaphragm rod 38 while compressing the set spring 58, the locking ring 44 is guided to reduce its diameter by the tapered ring guide hole 40d. However, when it reaches the second locking groove 43 through the fitting hole 40c, its diameter increases until it comes into contact with the groove bottom of the second locking groove 43 by its own repulsive force. The engaged state with the stop groove 42 is maintained.

  In this manner, the locking ring 44 is simultaneously engaged with the first and second locking grooves 42 and 43 by one simple operation of pushing the holding plate 41 into the fitting hole 40c along the axial direction. The holding plate 41 connected to the valve shaft 27 can be connected to the diaphragm rod 38 in the axial direction. Moreover, due to the arrangement of the set spring 58, the inner surface of the first locking groove 42 on the set spring 58 side, the locking ring 44, and the locking ring 44 and the second locking groove 43 on the pressure reducing valve body 10 side. The inner side surfaces are held in contact with each other.

  Referring again to FIG. 1, the first body member 12 is opposite to the second body member 13, and the diaphragm cover is formed in a bottomed cylindrical shape having an end wall 45 a on the opposite side to the first body member 12. 45 is fastened so as to sandwich the peripheral edge of the diaphragm 8 with the first body member 12, and the diaphragm rod 38 is connected to the center of the diaphragm 8. That is, the diaphragm rod 38 has a shaft portion 38a extending in the direction opposite to the opening direction of the connecting hole 40 coaxially and integrally, and this shaft portion 38a is a central portion of the diaphragm rod 38 and the diaphragm 8. A ring-shaped first retainer 46 sandwiched between and a ring-shaped second retainer 47 sandwiching the center portion of the diaphragm 8 between the first retainer 46 and a protruding portion from the second retainer 47 The center portion of the diaphragm 8 is connected to the shaft portion 38a by caulking a part of the outer periphery of the shaft portion 38a and engaging the second retainer 47. An annular seventh seal member 48 is interposed between the diaphragm rod 38 and the first retainer 46.

  Thus, a pressure acting chamber 49 is formed between the diaphragm 8 and the first body member 12 so that one surface of the diaphragm 8 faces, and the other surface of the diaphragm 8 is controlled between the diaphragm 8 and the diaphragm cover 45. A pressure chamber 50 is formed, and the first body member 12 is provided with a communication passage 51 that communicates the outlet passage 19 communicating with the decompression chamber 18 with the pressure working chamber 49. In addition, a coiled diaphragm spring 52 accommodated in the control pressure chamber 50 is contracted between the diaphragm cover 45 and the diaphragm 8. The diaphragm cover 45 is connected to a negative pressure introducing pipe 53 that communicates with the control pressure chamber 50. The negative pressure introducing pipe 53 is connected to the engine, and introduces the intake negative pressure of the engine into the control pressure chamber 50. It is like that.

  A support cylinder 54 that protrudes toward the control pressure chamber 50 is integrally provided at the center of the end wall 45a of the diaphragm cover 45 so that the diaphragm cover 45 can be rotated from the outside. A screw 55 is screwed into the support cylinder 54 so that one end of the screw 55 enters the control pressure chamber 50, and an annular eighth seal member 56 is interposed between the support cylinder 54 and the adjustment screw 55. The The control pressure chamber 50 accommodates a bottomed cylindrical spring seat member 57 that covers the support tube 54 by bringing one end of the adjustment screw 55 into contact with the central portion of the closed end. The spring 52 is contracted between the spring seat member 57 and the second retainer 47 fixed to the diaphragm 8 at the center. Thus, the spring seat member 57 can be moved back and forth by rotating the adjusting screw 55, whereby the spring load of the diaphragm spring 52 can be adjusted.

  In the pressure reducing valve 6, when the diaphragm 8 is bent toward the control pressure chamber 50 against the spring force of the diaphragm spring 52 due to the pressure in the pressure acting chamber 49, that is, the pressure in the pressure reducing chamber 18, the diaphragm rod 38 is moved. By pulling the valve shaft 27 through the holding plate 41, the pressure reducing valve body 10 is seated on the pressure reducing valve seat 25 with the seating surface 10c closed, and the diaphragm 8 is lowered by the pressure drop in the pressure working chamber 49. When the pressure acting chamber 49 is bent, the diaphragm rod 38 pushes the valve shaft 27 via the holding plate 41, so that the pressure reducing valve body 10 separates the seating surface 10c from the pressure reducing valve seat 25 and opens. By repeating the seating and separation of the pressure reducing valve body 10 with respect to the pressure reducing valve seat 25, the high pressure gas fuel from the valve chamber 31 is reduced and guided to the pressure reducing chamber 18.

  By the way, as described above, the connecting hole 40 of the diaphragm rod 38 is provided with a set spring 58 that biases the holding plate 41 toward the valve opening side of the pressure reducing valve body 10. The inner surface on the set spring 58 side of the first locking groove 42 and the inner surface of the locking ring 44 and the second locking groove 43 of the diaphragm rod 38 on the pressure reducing valve body 10 side are in contact with each other. Therefore, when the diaphragm 8 is pushed or pulled with respect to the valve shaft 27, the above-mentioned contact state can be maintained, and therefore, the phenomenon of separation / contact of the contact portion that causes abnormal noise can be prevented. Can do.

  Further, since a minute radial gap exists between the reduced-diameter shaft portion 27a of the valve shaft 27 and the locking recess of the holding plate 41, a coaxial accuracy error between the valve shaft 27 and the diaphragm rod 38 is reduced by the minute gap. Therefore, it is possible to secure a proper closed state of the pressure reducing valve body 10.

  Further, when the pressure reducing valve body 10 is closed, the opposing surfaces of the second enlarged-diameter shaft portion 27c and the holding plate 41 are brought into contact with each other due to the pulling force of the diaphragm rod 38. Since the convex spherical surface 59 is formed on one side and the concave tapered surface 60 is formed on the other side, the tilting of the diaphragm rod 38 with respect to the valve shaft 27 is caused by the swinging action of the spherical surface 59 and the tapered surface 60. This can be absorbed and contributes to the proper closing of the valve body 10 for pressure reduction.

  Furthermore, when the pressure reducing valve body 10 is in the closed state, the pressure reducing valve body 10 and the back pressure chamber 35 facing the upper end surface of the valve shaft 27 communicate with the pressure reducing chamber 18 through the communication hole 36. 10 and the pressure applied to both end faces of the valve shaft 27 are balanced, and the thrust force due to the pressure difference is prevented from acting on the pressure reducing valve body 10 and the valve shaft 27, so that the pressure reducing valve body 10 is properly closed. Can be secured.

  The solenoid 9 of the shut-off valve 7 includes a bobbin 62 having a center hole 61 and formed of a synthetic resin, a coil 63 wound around the bobbin 62, and a synthetic resin that covers the bobbin 62 and the coil 63. One end is inserted and fixed into the cover 64 made of metal and the receiving hole 15 of the second body member 13 in the body 5, and the other end is inserted into one end of the center hole 61 of the bobbin 62. A guide tube 65 made of material, a fixed core 66 which closes the other end of the guide tube 65 and is coaxially fixed to the guide tube 65, has one end opened, and the other end closed by an end wall 67a. A solenoid housing 67 made of a magnetic material, which is formed in a bottom cylindrical shape and covers the bobbin 62, the coil 63, and the covering portion 64, and is screwed into a screw hole portion 15a of the accommodation hole 15 in the second body member 13. A cylindrical portion 68a having a male thread engraved on the outer periphery is integrally formed, a holder 68 that closes one end opening of the solenoid housing 67, and a slidable fit in the guide tube 65 facing the fixed core 66. A movable core 69 to be joined, and a return spring 70 contracted between the fixed core 66 and the movable core 69 are provided.

  The end wall portion 67a of the solenoid housing 67 is integrally provided with a cylindrical portion 67b that is fitted to the other end side of the center hole 61 of the bobbin 62, and the fixed portion that is fitted into the cylindrical portion 67b. Bolts 72 that are inserted through the central portion of the end wall portion 67a are screwed into the core 66. In addition, a coupler portion 64 a that protrudes from the solenoid housing 67 to the outside is integrally formed on the covering portion 64.

  The guide cylinder 65 has a small diameter in which one end is coaxially inserted into the screw hole 15 a of the accommodation hole 15 in the second body member 13 and the other end is fitted to one end of the center hole 61 of the bobbin 62. And a large-diameter portion 65b formed coaxially with one end of the small-diameter portion 65a so as to be larger in diameter than the small-diameter portion 65a and to be fitted in the fitting hole portion 15b of the receiving hole 15. And are fixed to the second body member 13.

  The guide cylinder 65 has a small diameter hole 74 into which one end of the fixed core 66 is fitted and the movable core 69 is inserted coaxially. The small diameter hole 74 has a larger diameter than the small diameter hole 74, and the large diameter portion 65b. A large-diameter hole 75 opened at one end of the large-diameter portion is formed so as to be coaxially connected at an axially intermediate portion of the large-diameter portion 65b.

  Moreover, one end of the large-diameter portion 65b abuts on the holding portion 28a of the valve element guide member 28 from the side opposite to the second inward flange portion 13b, and the guide cylinder 65 is connected to the second inward flange portion 13b. An annular ninth seal member that is fixed to the second body member 13 so as to sandwich the valve element guide member 28 therebetween and elastically contacts the inner periphery of the fitting hole 15b. 76 and a second back-up ring 77 are mounted on the outer periphery of the large-diameter portion 65b.

  The guide tube 65 is formed with an annular step portion 65c facing the second inward flange portion 13b at the connecting portion of the small diameter portion 65a and the large diameter portion 65b. One end of the cylindrical portion 68a of the holder 68 screwed into the 15 screw hole portions 15a contacts the step portion 65c. Therefore, the holder 68 holds the large-diameter portion 65b of the guide cylinder 65 and the holding portion 28a of the valve element guide member 28 between the second inward flange portion 13b, and the holding hole 15b. The screw 8 is screwed into the screw hole 15a at the end opposite to the diaphragm 8.

  Thus, the bolts 72 are screwed into the fixed core 66 at the other end of the guide cylinder 65 fixed to the second body member 13 of the body 5 and tightened, whereby the bobbin 62 and the coil 63 are tightened. The holder 68 fixed to the second body member 13 of the body 5 comes into contact with one end opening of the solenoid housing 67 that covers the covering portion 64, and the magnetic flux generated when the coil 63 is energized. The solenoid housing 67 and the holder 68 form a magnetic path.

  The shut-off valve 7 includes a shut-off valve body 78 and a sub-valve body 79 assembled to the shut-off valve body 78 so as to enable relative movement of the shut-off valve body 78 within a predetermined range. The sub-valve element 79 is formed at the end of the movable core 69 opposite to the fixed core 66. The shut-off valve body 78 is inserted into the fitting hole portion 15b of the housing hole 15 of the second body member 13 from the opposite side to the diaphragm 8, and the shut-off valve body 78 contains the pressure reducing valve 6 therein. The pressure-reducing valve body 10 is accommodated coaxially.

  The shut-off valve body 78 includes a stepped cylindrical portion 78a coaxially covering the large diameter cylindrical portion 28b and the small diameter cylindrical portion 28c of the valve body guide member 28, and radially outward from one end of the stepped cylindrical portion 78a. A pilot port that overhangs and faces the holding portion 28a of the valve element guide member 28 from the side opposite to the second inward flange 13b, and a pilot port coaxial with the central axis of the stepped cylindrical portion 78a at the center. The end wall portion 78c is integrally formed with an end wall portion 78c that closes the other end portion of the stepped cylindrical portion 78a, and is formed into a bottomed cylindrical shape. On the outer surface of the central portion of the portion 78c, a protrusion 78d that forms a part of the pilot port 80 is integrally protruded toward the fixed core 66 side. The stepped cylindrical portion 78 a of the shut-off valve body 78 is coaxially inserted into the small diameter hole 74 of the guide cylinder 65, and the flange portion 78 b is disposed coaxially within the large diameter hole 75 of the guide cylinder 65. Is done.

  An annular first rubber seal 81 is embedded in the flange portion 78b of the shutoff valve body 78 so as to face the surface of the holding member 28a of the valve body guide member 28 opposite to the second inward flange portion 13b. The shut-off valve seat 82 on which the first rubber seal 81 can be seated is separate from the second body member 13 of the body 5 and is fixed to the second body member, in the illustrated example, the valve body. A blocking valve seat 82 that is formed in the guide member 28 and protrudes in an annular shape so that the first rubber seal 81 is seated on the holding portion 28 a of the valve element guide member 28 is formed.

  By the way, an annular recess 83 is provided on the outer periphery of the large diameter portion 65b of the guide cylinder 65 between the ninth seal member 76 and the holding portion 28a of the valve body guide member 28, and an inlet passage 84 leading to the annular recess 83 is formed. A connection member 85 provided on the second body member 13 for connecting a conduit for guiding high-pressure gas fuel to the inlet passage 84 is attached to a side surface of the second body member 13.

  The large diameter portion of the guide cylinder 65 is provided with a plurality of first communication holes 86 that allow the annular recess 83 to communicate with the large diameter hole 75, and the large diameter cylindrical portion 28 b of the valve element guide member 28 includes the pressure reducing portion. A plurality of second communication holes 87 that communicate with the valve chamber 31 of the valve 6 are provided. Thus, the inlet passage 84, the annular recess 83, the first communication hole 86, and the second communication hole 87 constitute a high-pressure passage 88 that guides high-pressure gas fuel to the pressure reducing valve 6 side. The shut-off valve element 78 and the shut-off valve seat 82 of the shut-off valve 7 are disposed between the first and second communication holes 86... 87 in the middle of the high-pressure passage 88.

  In one of the shut-off valve body 78 and the sub-valve body 79, in the illustrated example, the sub-valve body 79 is provided with a recess 90 coaxial with the central axis of the shut-off valve body 78 and the sub-valve body 79. An insertion portion 91 to be inserted is provided on the other side of the shut-off valve body 78 and the sub-valve body 79, in this embodiment on the shut-off valve body 78, and a part of the stepped cylindrical portion 78a of the shut-off valve body 78 is provided. The end wall portion 78c is inserted into the concave portion 90 as the insertion portion 91. Thus, a pilot valve chamber 92 is formed between the sub-valve element 79 and the shutoff valve element 78, and the first communication hole 86 communicating with the inlet passage 84 via the annular recess 83 is provided in the pilot valve chamber 92. A first passage 93 is formed between the guide cylinder 65 and the shutoff valve body 78, and a second communication hole communicating with the valve chamber 31 is provided between the valve body guide member 28 and the shutoff valve body 78. A second passage 94 is formed to communicate 87 to the pilot port 80.

  A second rubber seal 95 is embedded in the sub-valve element 79 so as to be positioned at the central portion of the closed end of the recess 90, and the second rubber seal 95 is provided on the protrusion 78 d of the insertion portion 91 of the shut-off valve body 78. The state in which the pilot port 80 is closed by contact with each other (the state shown in FIG. 1) and the state in which the second rubber seal 95 is separated from the protrusion 78d to open the pilot port 80 are deenergized and energized. The movable core 69, that is, the sub-valve element 79 is operated so as to be switched according to the above.

  One of the inner periphery of the recess 90 and the outer periphery of the insertion portion 91, in this embodiment, an annular groove 97 provided on the outer periphery of the insertion portion 91 can be elastically deformed so as to expand and contract in response to the action of an external force. A ring 98 having a shape is mounted so that a part protrudes outward from the annular groove 97 when no external force is applied. Further, the other of the inner periphery of the recess 90 and the outer periphery of the insertion portion 91, in the illustrated example, the opening end inner periphery of the recess 90, the insertion portion 91 is inserted into the recess 90, and the shutoff valve body 78 and the When the sub-valve bodies 79 are assembled to each other, an engaging projection 99 is provided so as to project inward in the radial direction by applying the external force to the ring 98 and overcoming the ring 98.

  In addition, the relative positions of the ring 98 and the engagement projection 99 in the state where the shutoff valve body 78 and the sub-valve body 79 are assembled with each other are such that the solenoid 9 is in a non-energized state and in the non-operating state. When the pilot port 80 is closed as shown in FIG. 1, a gap along the moving direction of the shutoff valve body 78 and the auxiliary valve body 79 is formed between the ring 98 and the engagement protrusion 99. However, when the solenoid 9 is energized and the sub-valve element 79 moves to the side where the pilot port 80 is opened, the engagement protrusion 99 is moved to the ring 98 after the pilot port 80 is opened. And the shut-off valve body 78 is set to move to the valve opening position side.

  In addition, when the insertion portion 91 is inserted into the concave portion 90 in order to assemble the shut-off valve body 78 and the sub-valve body 79 to the engagement protrusion 99, the insertion projection 91 moves in accordance with the advancement of the insertion portion 91. A tapered portion 99a is formed to apply an external force in the direction accommodated in the annular groove 97 to the C-shaped ring 98.

  In such a shut-off valve 7, when the engine is stopped, the movable core 69 is moved away from the fixed core 66 by the spring force of the return spring 70 due to the deenergization of the coil 63, and as shown in FIG. The first rubber seal 81 of the valve body 78 is seated on the shut-off valve seat 82 and the first and second communication holes 86... 87 are blocked, and the second rubber seal 95 of the sub-valve body 79 is projected. By closing the pilot port 80 in contact with 78d, the pilot valve chamber 92 and the second passage 94 are also shut off, and the supply of high-pressure gas fuel to the valve chamber 31 is stopped.

  On the other hand, when the coil 63 is energized at the start of engine operation, the movable core 69 first moves toward the fixed core 66 only by separating the second rubber seal 95 of the sub-valve element 79 from the projection 78d forming the pilot port 80. Then, the second passage 94 communicating with the valve chamber 31 via the second communication holes 87... Communicates with the pilot valve chamber 92 via the pilot port 80. As a result, high-pressure gas fuel gradually flows from the inlet passage 84 to the pilot port 80 through the annular recess 83, the first communication hole 86, the first passage 93 and the pilot valve chamber 92. As a result, the difference in pressure acting on the shutoff valve body 78 from both sides is reduced.

  Thus, when the driving force of the solenoid 9 overcomes the force in the valve closing direction based on the differential pressure acting on the shutoff valve body 78, the engagement protrusion 99 is engaged with the ring 98. The sub-valve element 79 connected to the shut-off valve element 78, that is, the movable core 69 further moves to the fixed core 66 side, and the first rubber seal 81 of the shut-off valve element 78 moves away from the shut-off valve seat 82. The gas fuel flows from the high-pressure passage 88 to the valve chamber 31 through the communication hole 36. At that time, the seal holding member 34 sandwiched between the valve body guide member 28 and the valve seat member 26 includes a first end plate 34a that contacts the valve body guide member 28 side and a first end plate 34a that contacts the valve seat member 26 side. Since the two end plates 34b and a plurality of support posts 34c that integrally connect the both end plates 34a and 34b are formed, the second communication holes 87 and the valve chamber 31 are provided between the adjacent support posts 34c and 34c. The flow path communicates with each other and does not hinder the flow of gas fuel from the high pressure passage 88 to the valve chamber 31 side.

  Next, a second embodiment of the present invention shown in FIG. 4 will be described.

  In the second embodiment, in the pressure-reducing valve body 10, the valve cylinder 10b having the seating surface 10c is fitted to the mandrel 10a so that the upper end thereof constitutes the annular shoulder 10d. At that time, a seal member 103 is interposed between the valve cylinder 10b and the mandrel 10a. When the pressure reducing valve body 10 is closed, that is, when the seating surface 10c is seated on the pressure reducing valve seat 25, the seal member 103 passes from the valve chamber 31 to the pressure reducing chamber through the fitting portion of the valve cylinder 10b and the mandrel 10a. 18 prevents high pressure gas from leaking. The fifth seal member 32 held by the seal housing 100 is in close contact with the outer peripheral surface of the mandrel 10a so as to be relatively slidable. Since other configurations are the same as those of the previous embodiment, portions corresponding to those of the previous embodiment in FIG. 4 are denoted by the same reference numerals, and redundant description is omitted.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the present invention described in the claims. Is possible. For example, the plurality of projections 34d of the seal holding member 34 can project from the outer end surface of the first end plate 34a, or project from both the first and second end plates 34a, 34b. it can.

6 .... Pressure reducing valve 8 .... Passive member (diaphragm)
DESCRIPTION OF SYMBOLS 10 ... Valve body 10d for pressure reduction ... Ring shoulder 18 ... Pressure reduction chamber 24 ... Valve hole 26 ... Valve seat member 27 ... Valve shaft 28 ... Valve body guide member 31 ...・ High pressure chamber (valve chamber)
32 ... Seal member (fifth seal member)
35 ... back pressure chamber 49 ... pressure working chamber 50 ... control pressure chamber 100 ... seal housing

Claims (3)

A valve seat member (26) having a valve hole (24) communicating between the high pressure chamber (31) and the decompression chamber (18), and a cylindrical valve body guide member (28) connected to the valve seat member (26) ), A pressure-reducing valve body (10) that is slidably supported by the valve body guide member (28) and opens and closes the valve hole (24) in cooperation with the valve seat member (26), The control pressure chamber (50) and the pressure action chamber (49) are partitioned by being connected to a valve shaft (27) connected to the pressure reducing valve body (10) so as to penetrate the valve hole (24). A passive member (8) disposed between the valve body (10) and the valve body guide member (28), and the valve body (10) opposite to the valve seat member (26). A back pressure chamber (35) facing the back surface of the side and communicating with the pressure reducing chamber (18) is provided, and the valve body guide member (28) is provided with the pressure reducing chamber. A cylindrical seal housing (100) facing the outer peripheral surface of the body (10) is formed, and the high pressure is slidably in close contact with the outer peripheral surface of the pressure reducing valve body (10). In a pressure reducing valve equipped with a seal member (32) for sealing between the chamber (31) and the back pressure chamber (35),
A composition that closes the opening of the seal housing (100) and surrounds the pressure-reducing valve body (10) so as to be axially movable, thereby preventing the seal member (32) from being detached from the seal housing (100). A pressure reducing valve characterized in that a resin seal holding member (34) is sandwiched between the valve seat member (26) and the valve element guide member (28). The pressure reducing valve according to claim 1,
The valve seat member (26) or the valve body guide member facing the end surface by receiving the clamping force of the valve seat member (26) and the valve body guide member (28) on the end surface of the seal holding member (34) A pressure reducing valve characterized by integrally forming a plurality of protrusions (34d) that are compressed and deformed by the end face of (28). The pressure reducing valve according to claim 1 or 2,
On the outer periphery of the pressure-reducing valve body (10), an annular shoulder (10d) facing the inner end surface of the seal holding member (34) opposite to the seal member (32) is formed. A pressure reducing valve comprising an assembly of the pressure reducing valve (6), wherein the member (26) and the valve body guide member (28) are connected to each other by press fitting.

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