JP2010237862A - Pressure reducing valve for gas - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To dispose a relief valve at a body with low-cost configuration avoiding an increase in the number of parts and assembling man-hours while optionally setting a gas discharge position in a pressure reducing valve for gas in which the relief valve opened when the pressure of a pressure reducing chamber becomes a predetermined pressure or higher to release pressure in the pressure reducing chamber to the outside is disposed at the body that holds a valve mechanism with a valve element interlocked with and connected to a pressure receiving member operated in response to the pressure in the pressure reducing chamber. <P>SOLUTION: The relief valve 21 includes a cylindrical joint part 74 provided integrally at the body 16 and having a sliding hole 75; a relief valve element 76 slidably fitted to the sliding hole 75; a cap 77 fitted and fixed to the outer end of the sliding hole 75; and a coil spring 78 provided between the relief valve element 76 and the cap 77. An annular relief valve seat 81 allowing the relief valve element 76 to be seated is formed at the inner end of the sliding hole 75, with a relief valve hole 80 communicating with the pressure reducing chamber, opened at the center part. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a valve hole in which a valve mechanism having a valve body accommodated in the valve chamber so as to be able to be seated on a valve seat facing a valve chamber communicating with a high-pressure passage is opened in a central portion of the valve seat. The valve body is accommodated and connected to a pressure passive member that operates according to the pressure of the decompression chamber that communicates with the pressure chamber, and opens when the pressure in the decompression chamber exceeds a predetermined pressure. The present invention relates to a gas pressure reducing valve in which a relief valve for releasing pressure to the outside is disposed in the body.

  A gas pressure reducing valve in which a relief valve for preventing the pressure in the pressure reducing chamber from rising abnormally due to a failure of the valve mechanism or the like is already known in Patent Document 1 or the like is already known. In this case, the relief valve is guided by the valve housing in a valve housing composed of a stepped cylindrical guide tube having a small diameter at one end and a cap that is press-fitted and fixed to the other end of the guide tube. The valve body and a coil spring that is contracted between the valve body and the valve housing are accommodated, and the valve housing is press-fitted into the body of the gas pressure reducing valve.

JP 2008-267558 A

  However, in the one disclosed in Patent Document 1, a valve housing is configured by a guide cylinder and a cap that is press-fitted and fixed to the guide cylinder. The number of parts increases, and press-fitting work to the body of the valve housing is performed. It is necessary and requires a lot of assembly work, resulting in high costs. Further, when the relief valve is opened, the pressure in the decompression chamber is released from the valve housing to the outside, and the decompression valve is disposed in the engine room so as to decompress the gas fuel supplied to the vehicle engine. In some cases, the gas is discharged into the engine room. However, in some vehicles, it is not preferable to discharge the gas into the engine room, and it may be desirable to discharge the gas to the atmosphere outside the engine room. In this case, it is possible to connect a joint to the cap and discharge the gas to the outside of the engine room via the hose connected to the joint. However, the number of parts increases due to the joint, and the joint is connected to the cap. The number of man-hours required is also increased, leading to an increase in cost.

  The present invention has been made in view of such circumstances, and it is possible to arbitrarily set a gas discharge position, while avoiding an increase in the number of parts and the number of assembly steps, and a relief valve in the body. An object of the present invention is to provide a gas pressure reducing valve that can be disposed.

  In order to achieve the above-mentioned object, the present invention provides a valve mechanism having a valve body accommodated in the valve chamber, which can be seated on a valve seat facing a valve chamber communicating with a high-pressure passage. The valve body is accommodated and linked to a pressure passive member that operates according to the pressure of the decompression chamber that opens to the valve hole that opens at the center of the chamber, and the pressure of the decompression chamber becomes equal to or higher than a predetermined pressure. In the gas pressure reducing valve in which the relief valve for opening the valve to release the pressure in the pressure reducing chamber to the outside is disposed in the body, the relief valve is formed in a cylindrical shape so that the hose can be connected and the hose is removed. A cylindrical joint part integrally provided in the body so that a retaining part for stopping is formed on the outer periphery, and a relief valve slidably fitted in a slide hole coaxially formed by the joint part The body and the outer end of the sliding hole, An annular relief valve seat comprising a cap to be fixed, a coil spring provided between the relief valve body and the cap, and capable of seating the relief valve body elastically biased by the coil spring Is formed at the inner end of the sliding hole by opening a relief valve hole communicating with the decompression chamber at a central portion, and the relief valve element is formed on the cap when the pressure of the decompression chamber becomes a predetermined pressure or more. Is provided with a release hole for releasing the pressure in the decompression chamber to the outside as the relief valve hole is opened by being separated from the relief valve seat.

  According to the above feature of the present invention, the relief valve includes a cylindrical joint portion that is provided integrally with the body, a relief valve body that is slidably fitted in a slide hole that the joint portion has coaxially, and a sliding valve. A cap fitted and fixed to the outer end of the moving hole, and a relief valve body and a coil spring provided between the caps, and the valve housing was assembled to the body by press-fitting etc. In comparison, the number of parts and assembly man-hours can be reduced, and the joint part is formed in a cylindrical shape so that the hose can be connected, and a hose retaining part is formed on the outer periphery of the joint part. The number of parts and the number of assembling steps can be reduced, and the cost can be reduced, as compared with the case of connecting body joint members. Moreover, by connecting the hose to the joint portion, the discharge position of the gas discharged as the relief valve is opened can be arbitrarily set by the hose.

It is a longitudinal cross-sectional view of the pressure reducing valve for gas. FIG. 2 is an enlarged view of a portion indicated by an arrow 2 in FIG. 1. FIG. 3 is an enlarged view of a portion indicated by an arrow 3 in FIG. 1. FIG. 4 is an enlarged sectional view taken along line 4-4 of FIG. FIG. 5 is an enlarged view of a part indicated by an arrow 5 in FIG. 1. FIG. 6 is a sectional view taken along line 6-6 of FIG. It is a disassembled perspective view of the 1st and 2nd body. It is a perspective view of the 1st body member for showing a to-be-attached part.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  The first embodiment of the present invention will be described with reference to FIGS. 1 to 8. First, in FIG. 1, this gas pressure reducing valve depressurizes compressed natural gas, which is a fuel gas, and supplies it to an engine (not shown). A body 16 in which first and second body members 18 and 19 are coupled to each other, and a diaphragm cover 17 formed by press molding of a thin metal and coupled to the body 16. The body 16 accommodates a valve mechanism 20 and a relief valve 21.

  The body 16 is formed by first and second body members 18 and 19 being fastened at a plurality of positions while overlapping vertically. In the central portion of the first body member 18, an accommodation hole 23 is provided that has an inward flange 22 projecting radially inward at the upper end and extends vertically. The accommodation hole 23 has a small diameter hole 23a, a screw hole 23b having a diameter larger than that of the small diameter hole 23a, and a large diameter hole 23c having a diameter larger than that of the screw hole 23b in order from the inward flange 22 side. The lower end of the large-diameter hole 23c is opened downward at the lower end surface of the first body member 18.

  A gas inlet 24 for introducing compressed natural gas before decompression is provided on the lower side surface of the first body member 18, and a high-pressure passage 25 coaxially connected to the gas inlet 24 is provided in the first body member 18.

  Referring also to FIG. 2, the valve mechanism 20 is driven by a diaphragm 28, and a metal guide member 30 that is airtightly fitted and fixed to the small-diameter hole 23 a of the accommodation hole 23, A valve seat 32 provided with a valve seat 34 facing the valve chamber 32 by forming a valve chamber 32 between the guide member 30 and being coupled to the guide member 30, and opening a valve hole 33 in the central portion; The valve shaft 35 is slidably fitted to the guide member 30 while penetrating the valve hole 33 loosely, and the valve shaft 35 can be seated on the valve seat 34 so that the valve shaft 35 can be seated in the valve chamber 32. And a valve body 36 made of a synthetic resin fitted on the outer periphery. The valve mechanism 20 is interposed between a high-pressure chamber 37 that communicates with the valve chamber 32 and a decompression chamber 38 that communicates with the valve hole 33. To be housed in the body 16 Attached to first body member 18, the the high pressure chamber 37 the high pressure passage 25 is communicated.

  A cylindrical portion 30a extending to the valve seat member 31 side is integrally provided on the outer periphery of the end portion of the guide member 30 on the valve seat member 31 side. The valve seat member 31 is press-fitted so as to contact the seat member 31. An annular first seal member 39 surrounding the valve hole 33 is mounted on the surface of the valve seat member 31 on the inward flange 22 side so as to be in close contact with the inward flange 22, and the valve chamber 32 is It is formed between the valve seat member 31 and the guide member 30 so that the outer periphery is defined by the cylindrical portion 30a.

  The annular high-pressure chamber 37 is formed between the outer periphery of the valve seat member 31 and the outer periphery of the guide member 30 on the valve seat member 31 side and the inner periphery of the small-diameter hole 23a in the accommodation hole 23, On the outer periphery of the guide member 30, an annular second seal member 40 that elastically contacts the inner periphery of the small diameter hole 23a is mounted.

  Further, a cylindrical filter 41 interposed between the high pressure chamber 37 and the valve chamber 32 surrounds the cylindrical portion 30 a of the guide member 30 between the guide member 30 and the valve seat member 31. The cylindrical portion 30 a is provided with a plurality of communication holes 42 for introducing the high pressure gas that has passed through the filter 41 from the high pressure chamber 37 into the valve chamber 32.

  The valve shaft 35 includes a valve body mounting shaft portion 35a, a connecting shaft portion 35b formed in a smaller diameter than the valve body mounting shaft portion 35a and coaxially connected to one end of the valve body mounting shaft portion 35a, and the valve body mounting. A guide shaft portion 35c that is formed to be slightly larger in diameter than the shaft 35a and that is coaxially connected to the other end of the valve body mounting shaft portion 35a is integrally formed, and the connecting shaft portion 35b loosely penetrates the valve hole 33. The guide shaft portion 35c is slidably fitted to the guide member 30 and is connected to the diaphragm 28 side.

  The valve body 36 is formed in a cylindrical shape so as to be mounted and fixed on the outer periphery of the valve body mounting shaft portion 35a of the valve shaft 35, and is seated on the valve seat 34 at one end of the valve body 36. A possible tapered seal surface 36a is formed, and an annular protrusion 36b that elastically engages with an annular locking groove 43 provided on one end outer periphery of the valve body mounting shaft portion 35a is provided.

  The guide member 30 slides in an insertion hole 44 into which a part of the valve body 36 mounted on the valve body mounting shaft portion 35a of the valve shaft 35 is inserted, and a guide shaft portion 35c of the valve shaft 35. A guide hole 45 formed to have a smaller diameter than the insertion hole 44 is provided so as to be fitted in a coaxial manner.

  In the insertion hole 44, a large diameter hole 44a, a medium diameter hole 44b having a smaller diameter than the large diameter hole 44a, and a small diameter hole 44c having a smaller diameter than the medium diameter hole 44b are coaxially arranged in this order from the valve chamber 32 side. An annular third seal member 46 that elastically slides on the outer periphery of the valve body 36 is inserted into the medium diameter hole 44b, and a third seal is inserted into the large diameter hole 44a. A ring plate-shaped presser plate 47 that prevents the member 46 from being detached from the medium diameter hole 44b is press-fitted. In other words, the third seal member 46 that elastically slides on the outer periphery of the valve body 36 is attached to the guide member 30.

  The guide hole 45 is smaller in diameter than the small diameter hole 44c of the insertion hole 44, and is smaller in diameter than the outer peripheral diameter of the valve body 36 with which the third seal member 46 is slidably contacted. The guide diameter D2, which is the diameter of the guide hole 45, is set smaller than the seal diameter D1 of the valve body 36 by the member 46.

  In FIG. 1 again, the screw hole 23 b of the accommodation hole 23 abuts on the guide member 30 and holds the guide member 30 and the valve seat member 31 between the inward flange 22 and a ring-shaped pressing member 48. Are screwed together. A screw hole 49 having a diameter larger than that of the guide shaft portion 35c of the valve shaft 35 is provided in the holding member 48 coaxially with the valve shaft 35 so as to insert an end portion of the guide shaft portion 35c. . Moreover, a tool (not shown) for rotating the pressing member 48 to engage with the screw hole 23b is detachably engaged with the end surface of the pressing member 48 opposite to the guide member 30. A bottomed engagement hole 50 is provided.

  The lower end opening of the receiving hole 23 is hermetically closed by the adjusting member 51. The adjustment member 51 has a large-diameter portion in which an annular fourth seal member 52 that elastically contacts the inner surface of the large-diameter hole 23c in the accommodation hole 23 is mounted on the outer periphery and fitted into the large-diameter hole 23c. 51a and a male screw 53 formed smaller in diameter than the large diameter portion 51a and screwed into the screw hole 49 of the pressing member 48 are formed coaxially and integrally with the large diameter portion 51a. And a small-diameter portion 51b continuously provided on the outer periphery, and a bottomed engagement hole 54 for engaging a tool (not shown) is provided at the outer end of the large-diameter portion 51a. Thus, when the male screw 53 is screwed into the screw hole 49 of the pressing member 48 and the tool is engaged with the engaging hole 54 and rotated, the adjusting member 51 is brought into an axis coaxial with the valve shaft 35. Advancing and retreating along the direction becomes possible.

  The adjusting member 51 is provided with a bottomed housing recess 55 opened to the valve shaft 35 side so as to be coaxial with the valve shaft 35, and a spring that is in contact with the end of the guide shaft portion 35 c of the valve shaft 35. A back coil spring 57 is contracted between the receiving member 56 and the closed end of the receiving recess 55. Thus, by adjusting the forward / backward position along the axial direction of the adjusting member 51 by rotating the adjusting member 51, the spring load of the back coil spring 57 can be adjusted.

  Referring also to FIG. 3, the second body member 19 is positioned at an intermediate portion along the axis of the valve mechanism 20 disposed on the first body member 18 side and orthogonal to the axis of the valve mechanism 20. A wall 58 is provided along the flat surface, and the second body member 19 is closer to the first body member 18 than the wall 58, and the decompression chamber forming hole 59 and the decompression chamber forming hole are sequentially formed from the wall 58 side. The fitting hole 60 having a diameter larger than 59 is provided so as to be coaxial with the accommodation hole 23 provided in the first body member 18 and connected to each other, and the wall 58 is opposite to the first body member 18. On the side, the second body member 19 is provided with a pressure action chamber forming hole 61 coaxially with the decompression chamber forming hole 59 and the fitting hole 60.

  On the other hand, as shown in FIG. 1, the first body member 18 is integrally provided with a fitting projection 18 a having a circular cross section that is coaxial with the accommodation hole 23, and the fitting projection 18 a The fitting hole 60 is fitted. Thus, an annular fifth seal member 62 that elastically contacts the inner periphery of the fitting hole 60 is mounted on the outer periphery of the fitting protrusion 18 a, and the fitting protrusion 18 a is inserted into the fitting hole 60. It will be fitted airtight.

  In a state where the fitting protrusion 18a is fitted in the fitting hole 60, the first and second body members 18, 19 surround the fitting protrusion 18a and are attached to the first body member 18. The sixth seal member 63 is joined so as to be interposed between the first and second body members 18 and 19, and the fitting protrusion 18 a and the wall 58 are not connected to each other. A decompression chamber 38 whose outer periphery is defined by the decompression chamber forming hole 59 is formed, and the decompression chamber 38 communicates with the valve hole 33 of the valve mechanism 20.

  Incidentally, a back pressure chamber 65 is formed in the accommodation hole 23 whose opening end is hermetically closed by the adjustment member 51 so that the end of the guide shaft portion 35c of the valve shaft 35 of the valve mechanism 20 faces. In the back pressure chamber 65, the second seal member 40 mounted on the outer periphery of the guide member 30 elastically contacts the inner surface of the small diameter hole 23 a in the accommodation hole 23, and the third seal mounted on the guide member 30. Since the member 46 is elastically in contact with the outer periphery of the valve body 36, the annular member formed between the guide member 30 and the valve seat member 31 and the first body member 18 in the small diameter hole 23a. The high pressure chamber 37 is hermetically isolated.

  The back pressure chamber 65 communicates with the decompression chamber 38 through a back pressure introduction path 66, and the back pressure introduction path 66 has the valve hole 33, the valve body 36, and the valve body of the valve shaft 35. A first passage portion 67 formed between the mounting shaft portions 35 a and a first passage portion 67 formed between the guide shaft portion 35 c of the valve shaft 35 and the guide member 30 so as to connect the first passage portion 67 and the back pressure chamber 65. 2 passage portions 68.

  The first passage portion 67 is axially arranged on at least one of the inner periphery of the valve body 36 and the outer periphery of the valve body mounting shaft portion 35a of the valve shaft 35, in the first embodiment, on the outer periphery of the valve body mounting shaft portion 35a. The valve body 36 is formed so as to form a fluid flow from the decompression chamber 38 to the back pressure chamber 65 between the valve shaft 35 and a flat first cutout 69 that extends. The valve body mounting shaft portion 35a is fitted into the valve body mounting shaft portion 35a, and the valve body mounting shaft portion 35a has the same cross-sectional shape over the entire axial length excluding the locking groove 43 at one end thereof. It is formed.

  The second passage portion 68 is flat on the outer periphery of the guide shaft portion 35c of the valve shaft 35 and the inner periphery of the guide member 30 in this embodiment 1, as shown in FIG. The second notch 70 is provided so as to extend in the axial direction, and the first and second notches 69 and 70 are continuously formed as a flush flat surface.

  Referring to FIG. 5, the relief valve 21 opens as the pressure in the decompression chamber 38 becomes equal to or higher than the set pressure. The relief valve 21 is formed in a cylindrical shape so that the hose can be connected to the hose. A cylindrical joint portion 74 that is integrally provided on the second body member 19 of the body 16 so that a retaining portion 74a that serves as a retaining member is formed on the outer periphery, and a sliding hole that the joint portion 74 has coaxially. A relief valve body 76 slidably fitted to 75, a cap 77 fitted and fixed to the outer end of the sliding hole 75, and a coil provided between the relief valve body 76 and the cap 77. And a spring 78.

  The relief valve body 76 has a cylindrical sliding cylinder portion 76a that is slidably fitted into the sliding hole 75, and is formed to have a smaller diameter than the sliding cylinder portion 76a. A cylindrical connecting cylinder part 76b coaxially connected to one end and a disk part 76c that closes one end of the connecting cylinder part 76b and projects the outer periphery radially outward from the outer periphery of the connecting cylinder part 76b are integrally provided. The connecting cylinder portion 76b is provided with a plurality of through holes 79.

  An annular relief valve seat 81 having a relief valve hole 80 communicating with the decompression chamber 38 opened at the center is provided at the inner end of the sliding hole 75. For example, an annular seat member 82 made of rubber is provided. It is possible to close the relief valve hole 80 by being seated on the relief valve seat 81, and is stuck to the disk portion 76c at the inner end of the relief valve body 76.

  The cap 77 is fixed to the joint portion 74 by, for example, press-fitting into the outer end of the sliding hole 75, and when the pressure in the decompression chamber 38 exceeds a predetermined pressure, the relief valve body 76 is A release hole 83 is provided for releasing the pressure in the decompression chamber 38 to the outside in response to the relief valve hole 80 being opened away from the relief valve seat 81.

  Referring to FIG. 1, the diaphragm 28 is made of a disk-shaped rubber plate in which at least the inner peripheral edge has a constant thickness in a natural state. In this embodiment, the entire diaphragm 28 is natural. In the state, it is formed in a disc shape with a constant plate thickness. The peripheral edge of the diaphragm 28 is sandwiched between the second body member 19 of the body 16 and the diaphragm cover 17 fixed to the second body member 19. The second body member 19 and the diaphragm 28 are sandwiched between the second body member 19 and the diaphragm 28. A pressure action chamber 86 whose outer periphery is defined by the pressure action chamber forming hole 61 of the second body member 19 is formed so as to face one surface of the diaphragm 28, and between the diaphragm 28 and the diaphragm cover 17 is formed. A spring chamber 87 is formed to face the other surface 28, and a coiled diaphragm spring 88 housed in the spring chamber 87 is contracted between the diaphragm cover 17 and the diaphragm 28.

  The diaphragm cover 17 is connected to a negative pressure introduction pipe 89 that communicates with the spring chamber 87. The negative pressure introduction pipe 89 is connected to the engine, and the intake negative pressure of the engine is introduced into the spring chamber 87. .

  In FIG. 3 again, a central hole 90 is provided in the central portion of the diaphragm 28, and a metal diaphragm rod 91 linked to and connected to the valve body 36 of the valve mechanism 20 has its one end on the spring chamber. The diaphragm rod 91 is inserted into the center hole 90 so as to protrude toward the 87 side, and the other end of the diaphragm rod 91 is in the shape of a bowl that comes into contact with one surface of the diaphragm 28 on the pressure acting chamber 86 side. A first retainer 92 is integrally provided. Further, the diaphragm rod 91 has a cylindrical portion integrally at one end thereof, and the cylindrical portion is caulked to form an engaging portion 91a bent outward. Between the engaging portion 91a and the other surface of the diaphragm 28 on the spring chamber 87 side, at least a metal second retainer 93 is sandwiched between the first retainer 92 and the inner peripheral edge portion of the diaphragm 28. In the first embodiment, the engaging portion 91a is directly engaged with the second retainer 93. Further, one end of a diaphragm spring 88 is brought into contact with the second retainer 93.

  Moreover, the diameter D3 of the outer peripheral surface from at least the first retainer 92 of the diaphragm rod 91 to the end surface on the engaging portion 91a side of the second retainer 93 is the position of the center hole 90 and the second retainer 93 along the radial direction of the diaphragm 28. Are set to be the same.

  By the way, the distance between the first and second retainers 92 and 93 is limited only by the diaphragm 28 sandwiched between the first and second retainers 92 and 93, but the distance decreases toward the outer side in the radial direction. Is set to be That is, the distance between the first and second retainers 92 and 93 on the radially inner end side is the maximum distance Cdmax, and the distance between the first and second retainers 92 and 93 is located on the radially outer end side. Is the minimum interval Cdmin, and the interval between the first and second retainers 92 and 93 is set so that the portion having the minimum interval Cdmin is positioned more radially outward of the diaphragm 28 than the portion having the maximum interval Cdmax. .

  In order to set the distance between the first and second retainers 92 and 93, the surface of the first retainer 92 facing the diaphragm 28 is inclined so as to approach the second retainer 93 as it goes radially outward. Formed.

  In addition, at least one of the surface of the first retainer 92 on the diaphragm 28 side and the surface of the second retainer 93 on the diaphragm 28 side, in this embodiment, the surface of the first retainer 92 on the diaphragm 28 side has a substantially V-shaped cross section. The plurality of grooves 100... 101 101 are formed so as to bite a part of the diaphragm 28. Thus, the grooves 100... Are formed in the first retainer 92 so as to be, for example, a concentric triple circle at a portion of the distance between the first and second retainers 92 and 93 that is the minimum distance Cdmin. The grooves 101... Are formed in the first retainer 92 so as to be, for example, concentric triple circles at the portion of the distance between the first and second retainers 92 and 93 that is the maximum distance Cdmax.

  On the other hand, a connecting shaft 94 is connected to the connecting shaft portion 35 b of the valve shaft 35 of the valve mechanism 20, and the connecting shaft 94 has a large-diameter shaft portion 94 a that makes one end abut against the first retainer 92. The small-diameter shaft portion 94b is coaxially connected to one end of the large-diameter shaft portion 94a so as to be inserted into the insertion hole 95 provided in the diaphragm rod 91, and is formed to have a smaller diameter than the large-diameter shaft portion 94a. The other end of the shaft portion 94a is integrally provided with a medium diameter shaft portion 94c that is coaxially connected.

  An annular seventh seal member 96 surrounding the small diameter shaft portion 94b is interposed between the large diameter shaft portion 94a and the first retainer 92 of the connecting shaft 94. A male screw 97 is engraved on the outer periphery of at least a portion of the small diameter shaft portion 94b protruding from the diaphragm rod 91 toward the spring chamber 87, and a nut 99 with a washer 98 interposed between the diaphragm rod 91 and the nut 99 is provided. When the male screw 97 is screwed and tightened, the connecting shaft 94 is connected to the center portion of the diaphragm 28 via the diaphragm rod 91 and the second retainer 93 integrally having the first retainer 92.

  The connecting shaft 94 penetrates the central portion of the wall portion 58 of the second body member 19 so as to be movable in the axial direction, and a guide member 104 made of synthetic resin for guiding the axial movement of the connecting shaft 94 includes Mounted on the wall 58.

  The guide member 104 includes a guide portion 104a formed in a cylindrical shape by forming a guide hole 106 into which the large-diameter shaft portion 94a of the connecting shaft 94 is slidably fitted, and the guide member 104a is radially outward from the guide portion 104a. And an engaging portion 104c projecting from the extending portion 104b at a position spaced apart from the guide portion 104a, and one end side of the guide portion 104a is integrally formed. The second body member 19 is inserted into a through-hole 105 provided in the central portion of the wall portion 58, and the engagement portion 104c is elastically engaged with the wall portion 58 of the body 16 so that the wall portion is engaged. 58.

  The extending portion 104b protrudes radially outward from the entire outer periphery of the axially intermediate portion of the guide portion 104a so as to face the wall portion 58 from the pressure acting chamber 86 side and to the wall portion 58. Are formed in a bowl shape with the opposite surface as a flat surface.

  The engaging portions 104c... Are integrally protruded from the extending portion 104b at a plurality of locations, for example, three locations, spaced at equal intervals in the circumferential direction so as to surround the guide portion 104a. It is formed to be inserted through the provided engagement holes 107 while being bent from one surface side of the wall portion 58 and to be elastically engaged with the other surface of the wall portion 58.

  An aspirator passage 108 communicating with the pressure reducing chamber 38 and the pressure acting chamber 86 is formed in the guide member 104 so as to penetrate the wall portion 58, and the aspirator passage 108 is formed as described above. One end is formed in the aspirator tube 109 integrally connected to the extending portion 104b. Thus, the wall 58 is provided with an aspirator hole 110 into which the aspirator tube 109 is fitted, and the other end of the aspirator tube 109 is decompressed while the guide member 104 is mounted on the wall 58. It is rushed into the chamber 38.

  The guide member 104 has a stopper portion 104d extending radially outward from an end portion of the guide portion 104a on the diaphragm 28 side, and the diaphragm 28 is displaced toward the side where the volume of the pressure acting chamber 86 is reduced. Are integrally provided.

  The large-diameter shaft portion 94a of the connecting shaft 94 is slidably fitted into the guide hole 106 of the guide member 104, and the annular outer periphery of the large-diameter shaft portion 94a is in sliding contact with the inner periphery of the guide hole 106. An eight seal member 111 is attached. Further, the medium diameter shaft portion 94 c of the connecting shaft 94 is inserted into the decompression chamber 38 from the guide hole 106, and one end portion of the valve shaft 35 in the valve mechanism 20 is inserted into the medium diameter shaft portion 94 c in the decompression chamber 38. Are concatenated.

  The intermediate diameter shaft portion 94c of the connection shaft 94 is provided with an engagement groove 112 that extends along a plane perpendicular to the axis of the connection shaft 94 and opens on the side surface of the connection shaft 94. A slit 113 extending between the end surface on the valve mechanism 20 side and the engagement groove 112 is provided so as to open to the side surface of the medium diameter shaft portion 94 c in the same direction as the engagement groove 112.

  On the other hand, a diameter-enlarged engagement portion 35d is provided at the tip of the connecting shaft portion 35b of the valve shaft 35 on which the valve body 36 is fixed, and the diameter-enlarged engagement portion 35d is engaged with the engagement groove 112. The connecting shaft portion 35 b is inserted into the slit 113 so as to be aligned, whereby the valve shaft 35 of the valve mechanism 20 is connected to one end portion of the connecting shaft 94. That is, the connecting shaft 94 is connected to the valve body 36 via the valve shaft 35.

  In such a gas pressure reducing valve, when the diaphragm 28 is bent toward the spring chamber 87 against the spring force of the diaphragm spring 88 by the pressure of the pressure acting chamber 86, the valve mechanism 20 is closed and the pressure is reduced. When the diaphragm 28 is bent toward the pressure working chamber 86 due to the pressure drop in the working chamber 86, the valve mechanism 20 is opened, and the opening and closing of the valve mechanism 20 is repeated, whereby the high-pressure compressed natural gas is decompressed. It is output from the gas outlet 114.

  Thus, the gas outlet 114 is provided in the second body member 19 so as to open the inner end on the inner surface of the decompression chamber forming hole 59 coaxially with the relief valve 21. That is, the gas outlet 114 communicates with the decompression chamber 38, and the connecting pipe portion 115 that forms the gas outlet 114 is provided integrally with the second body member 19 so as to protrude sideways from the second body member 19.

  Referring to FIGS. 6 and 7 together, the heating medium passage 118 through which the heating medium, for example, engine cooling water is circulated in the coupled state of the first and second body members 18, 19 is the first and second body members 18. , 19 and a sixth seal member 63, which is an annular elastic seal member that surrounds the heating medium passage 118 from the outside, is sandwiched between the first and second body members 18, 19.

  The heating medium passage 118 is formed in an arc shape surrounding the valve body 36 and the valve seat 34 when viewed in the direction along the axis of the valve shaft 35 in the valve mechanism 20, and also in the direction along the axis of the valve shaft 35. The valve seat 34 is disposed at substantially the same position, and in at least one of the coupling surfaces of the first and second body members 18, 19, in the first embodiment, the second body 19 is coupled to the first body member 18. A circular groove 119 for forming the heating medium passage 118 is provided on the surface, and the arc-shaped heating medium passage 118 is formed by dividing one circumferential direction of the groove 119 by the partition wall 120.

  Incidentally, the first body member 18 includes a medium inlet passage 121 that communicates with one end in the circumferential direction of the heating medium passage 118 and a medium outlet passage 122 that communicates with the other circumferential end of the heating medium passage 118 in the valve mechanism 20. It is provided so as to extend parallel to the axis of the valve shaft 35.

  Further, an annular seal mounting groove 123 for mounting the sixth seal member 63 is provided on the coupling surface of the first body member 18 to the second body member 19, and the medium inlet passage 121 and the medium outlet are mounted. A partition mounting groove 124 extending radially inward from the seal mounting groove 123 at a position corresponding to between the passages 122 is provided in the first body member 18.

  The partition wall 120 is integrally connected to the sixth seal member 63 so as to extend radially inward from one circumferential direction of the sixth seal member 63, and the sixth seal member 63 is connected to the seal mounting groove. When mounted on the partition 123, the partition 120 is mounted in the partition mounting groove 124. As a result, the partition wall 120 is positioned and fixed on the first body member 18 side where the medium inlet passage 121 and the medium outlet passage 122 are provided in the first and second body members 18 and 19.

  Thus, the partition wall 120 positioned and fixed on the first body member 18 side is fitted into the groove 119 on the second body member 19 side when the first and second body members 18 and 19 are joined, and the medium inlet passage. The heating medium passage 118 having a circular arc shape is formed by dividing one portion along the circumferential direction of the groove 119 at a portion corresponding to a portion between the medium outlet passage 121 and the medium outlet passage 122.

  Incidentally, bolt insertion holes 125... Are provided at a plurality of, for example, four places at equal intervals in the circumferential direction of the first body member 18, and the second body 19 individually corresponds to the bolt insertion holes 125. Screw holes 126 are provided, and the first and second body members 18 and 19 are coupled to each other by screwing and tightening bolts 127 inserted into the bolt insertion holes 125 to the screw holes 126. Is done. Therefore, the first and second body members 18 and 19 are coupled so as to be able to take a plurality of relative postures in which the circumferential relative position is changed, in the first embodiment, four relative postures in which the circumferential relative position is changed. Is done.

  The groove 119 includes a plurality of, for example, four shallow groove portions 119a, 119a, and a plurality of, for example, four deep groove portions 119b, 119b,... Disposed between the shallow groove portions 119a, 119a,. In the first example, corresponding to the four bolt insertion holes 125... 126 corresponding to each other being provided at four positions at equal intervals in the circumferential direction of the first and second body members 18 and 19, respectively. The two shallow groove portions 119a, 119a,... Are arranged at equal intervals in the circumferential direction, and the partition wall 120 is selectively fitted into one of the shallow groove portions 119a, 119a,.

  In FIG. 8, on the side surface of the first body member 18, there are provided flat attached portions 128 to be attached to the vehicle body which is a fixed support when the vehicle is mounted. Three bolt holes 129 are provided.

  Next, the operation of the first embodiment will be described. Fluid flow between the valve chamber 32 and the back pressure chamber 65 is allowed between the valve shaft 35 and the outer periphery of a metal valve shaft 35 provided in the valve mechanism 20. In this way, the valve body 36 made of synthetic resin is fitted, and the guide member 30 fixed to the first body member 18 of the body 16 and the outer periphery of the valve body 36 so as to guide the axial movement of the valve shaft 35. Since an annular third seal member 46 interposed between the valve chamber 32 and the back pressure chamber 65 is interposed therebetween, a seal that seals between the valve chamber 32 and the decompression chamber 38 between the valve shaft 35 and the valve body 36. It becomes unnecessary to interpose a member, and the number of parts can be reduced, thereby reducing the cost. In addition, since no sealing member is interposed between the valve body 36 and the valve shaft 35, the outer periphery of the valve shaft 35 and the inner peripheral shape of the valve body 36 can be simplified.

  In addition, since the third seal member 46 is mounted on the guide member 30 so as to elastically slidably contact the outer periphery of the valve body 36, it is not necessary to provide a seal member mounting groove or the like on the valve body 36 side. As a result, the shape of the valve body 36 can be further simplified.

  Further, a valve body mounting shaft portion 35a having a locking groove 43 for engaging the valve body 36 on the outer periphery of one end thereof is provided in a part of the valve shaft 35 made of metal so that the valve body 36 is fitted. Since the valve body mounting shaft portion 35a is formed so as to have the same cross-sectional shape over the entire length in the axial direction excluding the portion of the locking groove 43, when the valve shaft 35 is created by machining a metal base material. The number of parts to be deleted by cutting can be reduced, and the processing cost and material cost can be reduced.

  Further, at least one of the inner periphery of the valve body 36 and the outer periphery of the valve shaft 35, which is the outer periphery of the valve shaft 35 in the first embodiment, is a part of the back pressure introduction path 66 connecting the decompression chamber 38 and the back pressure chamber 65. Since the first notch 69 that forms the first passage portion 67 between the valve body 36 and the valve shaft 35 is provided extending in the axial direction, the back pressure introduction path 66 can be formed easily and inexpensively. It is not necessary to secure a space for forming the back pressure introduction path on the body member 18 side, and the body 16 can be downsized.

  Further, the valve shaft 35 integrally has a guide shaft portion 35c slidably fitted in a guide hole 45 provided in the guide member 30, and at least of the outer periphery of the guide shaft portion 35c and the inner periphery of the guide hole 45. On the other hand, in the first embodiment, on the outer periphery of the guide shaft portion 35 c, a part of the back pressure introduction passage 66 is formed and the second passage portion 68 connecting the first passage portion 67 and the back pressure chamber 65 is provided on the guide member 30. Since the second notch 70 formed between the valve shafts 35 extends in the axial direction, the back pressure introduction passage 66 can be easily configured together with the first passage portion 67.

  Further, since the guide hole 45 is formed to have a smaller diameter than the seal diameter D1 of the valve body 36 by the third seal member 46, a guide diameter D2 that is a diameter of the guide hole 45 that guides the valve body 36 and the valve shaft 35; Even if the ratio of the sliding portion of the valve shaft 35 to the length of the sliding portion (length of the sliding portion / guide diameter) is ensured so that the valve shaft 35 and the valve body 36 do not fall down or become galling, The length can be set short, and the pressure reducing valve can be downsized. That is, in order to prevent the valve shaft 35 and the valve body 36 from falling and galling, the length of the sliding portion / guide diameter is generally set to a certain value or more. By making it small, the length of the sliding portion can be reduced. Even if the guide diameter D2 and the seal diameter D1 are different, the back pressure introduction path 66 is formed between the valve shaft 35 and the valve body 36 and between the valve shaft 35 and the guide member 30, so that the valve shaft 35 can be configured with a simple configuration. Further, the back pressure can be applied to the entire end face of the valve body 36 on the side opposite to the diaphragm 28.

  Moreover, since the valve body 36 is made of a synthetic resin, durability and seating of the valve body 36 against high pressure can be secured, and the valve mechanism 20 depressurizes the compressed natural gas. The body 36 can be used optimally.

  By the way, the second body member 19 of the body 16 is provided with a relief valve 21 that opens when the pressure in the decompression chamber 38 becomes equal to or higher than a predetermined pressure and releases the pressure in the decompression chamber 38 to the outside. However, the relief valve 21 is formed in a cylindrical shape so that the hose can be connected, and a retaining portion 74a for retaining the hose is formed on the outer periphery. 19, a cylindrical joint portion 74 that is integrally provided with the joint 19, a relief valve body 76 that is slidably fitted into a slide hole 75 that the joint portion 74 has coaxially, and an outer end portion of the slide hole 75. A cap 77 to be fitted and fixed, and a coil spring 78 provided between the relief valve body 76 and the cap 77, and the relief valve body 76 elastically biased by the coil spring 78 can be seated. Ring A relief valve seat 81 is formed at the inner end of the sliding hole 75 with a relief valve hole 80 communicating with the decompression chamber 38 being opened at the center, and the relief valve body 76 is separated from the relief valve seat 81 in the cap 77. A release hole 83 is provided for releasing the pressure of the decompression chamber 38 to the outside in response to the relief valve hole 80 being seated and being opened.

  Therefore, the number of parts and assembly man-hours can be reduced as compared with a relief valve that is designed to assemble the valve housing to the body by press fitting or the like, and the joint portion 74 is formed in a cylindrical shape so that a hose can be connected. Since the retaining portion 74a is formed on the outer periphery of the joint portion 74, the number of parts and the number of assembling steps can be reduced and the cost can be reduced as compared with a case where a separate joint member is connected. Can do. Moreover, by connecting the hose to the joint portion 74, the discharge position of the gas discharged when the relief valve 21 is opened can be arbitrarily set by the hose.

  The diaphragm 28 has a central hole 90 at the center thereof, and is formed in a disk shape with a constant plate thickness at least at the inner peripheral edge in a natural state, and has a bowl-like shape that contacts the inner peripheral edge of the diaphragm 28. A metal diaphragm rod 91 that is integrally provided with the first retainer 92 and is linked to and connected to the valve body 36 of the valve mechanism 20 is inserted into the center hole 90 of the diaphragm 28, and one end of the diaphragm rod 91 is caulked. The second retainer 93 made of metal that sandwiches only the inner peripheral edge of the diaphragm 28 between the engaging portion 91a and the inner peripheral edge of the other surface of the diaphragm 28 is sandwiched between the first retainer 92 and this embodiment. 1, the engaging portion 91 a is directly engaged with the second retainer 93.

  Therefore, in a natural state, it is possible to reduce the cost by using the diaphragm 28 formed in a disc shape with a constant thickness at the inner peripheral edge portion, and compared with a screw tightening structure using a nut. The mass productivity is high and it is not necessary to consider screw loosening, and the reliability of the structure in which the inner peripheral edge of the diaphragm 28 is sandwiched between the first and second retainers 92 and 93 can be improved.

  Moreover, the outer peripheral surface diameter D3 from at least the first retainer 92 of the diaphragm rod 91 to the end surface on the engaging portion 91a side of the second retainer 93 is the position of the center hole 90 and the second retainer 93 along the radial direction of the diaphragm 28. Since they are set to be the same as each other, a part of the inner peripheral edge of the diaphragm 28 does not ride on other members other than the first and second retainers 92 and 93 during assembly, and the compression allowance of the diaphragm 28 is reduced. A desired value can be obtained. In addition, of the distance between the first and second retainers 92 and 93 restricted only by the diaphragm 28, the part having the minimum distance Cdmin is located radially outward from the part having the maximum distance Cdmax. The diaphragm 28 is compressed with a relatively large load between the first and second retainers 92 and 93 at a portion where Cdmin is obtained, thereby improving the sealing performance between the first and second retainers 92 and 93 and the diaphragm 28. Of the distance between the first and second retainers 92 and 93, the inner side portion of the portion with the minimum distance Cdmin needs to be compressed so as to pass through the portion with the minimum distance Cdmin. Load from the engaging portion 91a formed by caulking one end of the diaphragm rod 91 on the inner peripheral side of the first and second retainers 92 and 93 By acting, the second retainer 93 bends so as to exert an elastic force toward the side where the distance between the outer peripheral sides of the first and second retainers 91 and 92 is reduced, and therefore the elastic force decreases due to the deterioration of the diaphragm 28. Even if this occurs, it is possible to improve the anti-drop load.

  By the way, an arc-shaped heating medium passage 118 for allowing the heating medium to flow between the coupling surfaces of the first and second body members 18 and 19 constituting the body 16 is seen in a direction along the axis of the valve body 36 in the valve mechanism 20. In this embodiment, a circular groove 119 is formed so as to surround the valve body 36 and the valve seat 34, and a circular groove 119 for forming the heating medium passage 118 is formed on at least one of the coupling surfaces of the first and second body members 18, 19. 1, the second body member 19 is provided on the coupling surface of the second body member 19 to the first body member 18, and the first body member 18 is provided with a medium inlet passage 121 and a medium outlet passage 122 that communicate with both ends of the heating medium passage 118. However, the partition 120 that divides the circular groove 119 between the medium inlet passage 121 and the medium outlet passage 122 is positioned and fixed to the first body member 18.

  Therefore, even if the circumferential relative positions of both body members 18 and 19 are changed, the position of the partition wall 120 with respect to the medium inlet passage 121 and the medium outlet passage 122 is fixed, and the medium is placed at both end positions of the arc-shaped heating medium passage 118. Since the positions of the inlet passage 121 and the medium outlet passage 122 are determined, the heating medium can be circulated effectively, and it is not necessary to prepare a plurality of types of body members with different partition positions, thereby reducing costs. In addition, it is possible to eliminate the possibility of erroneous assembly.

  The first body member 18, which is one of the first and second body members 18, 19, is provided with a mounted portion 128 for attaching the body 16 to a fixed support such as a vehicle body. Since the gas outlet 114 leading to the decompression chamber 38 is provided in the second body member 19 which is the other of the two bodies 18 and 19, the opening direction of the gas outlet 114 when the body 16 is attached to the vehicle body or the like is set in a desired direction. Can be changed.

  Further, since the partition wall 120 is integrally provided in an annular sixth seal member 63 that is sandwiched between the coupling surfaces of the first and second body members 18 and 19 and seals the heating medium passage 118 from the outside, the partition wall 120 is provided. By providing the partition wall 120, it is possible to avoid the increase in the cost and the number of parts formed on the body, and to configure the partition wall 120 easily and at low cost. The partition wall 120 is fitted into the groove 119 and the heating medium passage 118 is formed. It is possible to securely seal between the both ends.

  Further, the groove 119 has a plurality of shallow groove portions 119a... And a plurality of deep groove portions 119b disposed between the shallow groove portions 119a, and the partition 120 is selectively fitted into one of the shallow groove portions 119a. As a result, the groove 119 is divided and the arc-shaped heating medium passage 118 is formed. Therefore, the partition wall 120 has elasticity, so that it fits into the shallow groove portion 119a of the groove 119 even though it has low rigidity and is easy to fall down. By combining, it becomes easy to maintain the rigidity of the partition 120, and the tightening margin management of the partition 120 becomes easy.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. Is possible.

16 ... Body 20 ... Valve mechanism 21 ... Relief valve 25 ... High pressure passage 32 ... Valve chamber 33 ... Valve hole 34 ... Valve seat 36 ... Valve body 38 ... · Decompression chamber 74 ··· Joint portion 74a · Preventing portion 75 · Sliding hole 76 · Relief valve element 77 · Cap 78 · Coil spring 80 · Relief valve hole 81 · ..Relief valve seat 83 ... Release hole

Claims (1)

  A valve having a valve body (36) accommodated in the valve chamber (32) which can be seated on the valve seat (34) facing the valve chamber (32) leading to the high pressure passage (25) on the body (16). The valve body (36) is connected to a pressure passive member (28) that operates according to the pressure of the decompression chamber (38) that communicates with the valve hole (33) that opens to the center of the valve seat (34). And a relief valve (21) that opens and releases the pressure in the decompression chamber (38) to the outside when the pressure in the decompression chamber (38) exceeds a predetermined pressure. In the gas pressure reducing valve disposed in the body (16), the relief valve (21) is formed in a cylindrical shape so that a hose can be connected, and a retaining portion (74a) that prevents the hose from being detached is provided on the outer periphery. So as to be formed integrally with the body (16). A cylindrical joint portion (74), a relief valve body (76) slidably fitted into a slide hole (75) that the joint portion (74) has coaxially, and the slide hole (75) ) And a coil spring (78) provided between the relief valve element (76) and the cap (77), and the coil spring (78). An annular relief valve seat (81) capable of seating the relief valve body (76) that is elastically energized by a pressure relief valve hole (80) communicating with the decompression chamber (38) in the center. The relief valve element (76) is formed at the inner end of the sliding hole (75) so as to open, and when the pressure in the decompression chamber (38) becomes a predetermined pressure or higher in the cap (77). The relief valve hole (80) is opened by separating from the relief valve seat (81). In response to being, a decompression chamber (38) gas pressure reducing valve, wherein the release holes (83) that is provided for releasing the pressure on the outside of.

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