JP7567387B2 - Pressure reducing valve - Google Patents

Description

The present invention relates to a pressure reducing valve.

As described in Patent Document 1, for example, there is a pressure reducing valve that reduces the pressure of a fluid supplied from a primary port (hereinafter referred to as primary pressure) to a predetermined pressure or less and sends it to a secondary port. Such a pressure reducing valve includes a body having a gas flow path communicating with the primary port and the secondary port, a valve seat disposed in the gas flow path, a valve body that moves toward and away from the valve seat, and a biasing member that biases the valve body in a direction to move it away from the valve seat. The valve body moves according to the pressure difference between the primary pressure and the pressure reduced by the pressure reducing valve (hereinafter referred to as secondary pressure) and the biasing force of the biasing member. The opening of the pressure reducing valve changes according to the position of the valve body, thereby adjusting the secondary pressure to a predetermined pressure or less.

JP 2017-126269 A

However, in the above conventional configuration, when the valve is closed with the valve disc seated on the valve seat, the valve disc is pressed against the valve seat in response to the secondary pressure, which can cause the valve seat to deform excessively. As a result, the valve seat becomes more susceptible to deterioration, which can lead to, for example, a shortened lifespan.

The object of the present invention is to provide a pressure reducing valve that can suppress excessive deformation of the valve seat.

The pressure reducing valve that solves the above problem includes a body having a gas flow path, a valve seat arranged in the gas flow path, a valve body arranged downstream of the valve seat in the gas flow path and moving toward and away from the valve seat, a biasing member that biases the valve body in a direction to move it away from the valve seat, and at least one seal member attached to the outer circumferential surface of the valve body, the valve body including a head that can be seated on the valve seat and an abutment portion that is located closer to the head than the tip seal member of the at least one seal member that is provided at a position closest to the head, and the body includes a stopper that restricts the movement of the valve body upstream by abutting against the abutment portion.

According to the above configuration, the abutment portion abuts against the stopper, restricting the valve body from moving upstream, thereby preventing the valve seat from being excessively deformed, and thus preventing a decrease in the lifespan of the valve seat.

From the viewpoint of not deforming the valve seat excessively, it is desirable that the abutting portion abuts against the stopper as soon as possible when the valve body moves upstream. On the other hand, from the viewpoint of appropriately reducing the primary pressure, it is desirable to not restrict the movement of the valve body upstream as much as possible so that the valve body can be firmly seated on the valve seat and cut off the flow of fluid when the pressure reducing valve is closed. Therefore, in order to seat the valve body firmly on the valve seat while suppressing excessive deformation of the valve seat, it is necessary to precisely specify the position where the movement of the valve body upstream is restricted and to prevent variation for each manufactured individual. To achieve this, it is required to increase the dimensional accuracy of the valve body and the body as much as possible. Specifically, it is necessary to reduce the variation in the relative position (distance) between the head of the valve body and the abutting portion, and the relative position (distance) between the mounting position of the valve seat on the body and the stopper. However, for example, when manufacturing the valve body and the body, dimensional tolerances are set, so there is a limit to how high the dimensional accuracy of the entire part can be increased.

In this regard, in the above configuration, the abutment portion is provided closer to the head than the tip seal member. In other words, the abutment portion is provided in a position close to the head. Therefore, it is possible to reduce the variation in the relative position between the head and the abutment portion compared to when the abutment portion is provided in a position away from the head. Also, since the stopper is provided in a position close to the mounting position of the valve seat in correspondence with the head and abutment portion of the valve body, it is possible to reduce the variation in the relative position between the mounting position of the valve seat and the stopper. This makes it possible to appropriately regulate the secondary pressure while suppressing excessive deformation of the valve seat.

In the pressure reducing valve, the valve body further includes a main body having a side hole that opens at a position closer to the head than the tip seal member in the valve body, and a vertical hole that communicates with the side hole and communicates with the downstream side of the valve body in the gas flow path, and the abutment portion is preferably provided at a position closer to the head than the side hole in the valve body.

According to the above configuration, the abutment portion is provided at a position preferably close to the head portion. This makes it possible to further reduce the variation in the relative position between the head portion and the abutment portion. Furthermore, the stopper is provided at a position preferably close to the mounting position of the valve seat, corresponding to the head portion and the abutment portion of the valve body. This makes it possible to further reduce the variation in the relative position between the mounting position of the valve seat and the stopper.

In the pressure reducing valve, the valve body further includes a main body having a side hole that opens to a position in the valve body closer to the head than the tip seal member, and a vertical hole that communicates with the side hole and communicates with the downstream side of the valve body in the gas flow path, and the abutment portion is preferably provided at a position farther from the head than the side hole in the valve body.

According to the above configuration, when the abutment portion abuts against the stopper, the force acting from the stopper on the abutment portion is less likely to affect the portion of the valve body in which the side hole is provided. This makes it possible to prevent the side hole from being deformed even if the abutment portion abuts against the stopper repeatedly.

In the above pressure reducing valve, it is preferable that the stopper is formed as a part of the body.
According to the above-mentioned configuration, the variation in the relative position between the mounting position of the valve seat and the stopper can be further reduced, compared to the case where the stopper is formed separately from the body.

In the above pressure reducing valve, it is preferable that the stopper is formed separately from the body and is disposed adjacent to the valve seat on the downstream side of the valve seat.
According to the above-mentioned configuration, when the valve is closed, the stopper is sandwiched between the valve seat and the valve body, so that the impact when the contact portion contacts the stopper is absorbed by the valve seat, thereby reducing the impact noise when the contact portion contacts the stopper.

In the above pressure reducing valve, it is preferable that a contact area of the valve seat with the stopper is larger than a contact area of the valve seat with the head.
According to the above-described configuration, it is possible to suppress the valve seat from being excessively deformed by the biasing force of the valve body received via the stopper.

The present invention makes it possible to prevent excessive deformation of the valve seat.

FIG. 2 is a schematic cross-sectional view of the pressure reducing valve of the first embodiment. FIG. 2 is a schematic enlarged cross-sectional view of the vicinity of a valve body and a valve seat in the pressure reducing valve of the first embodiment. FIG. 6 is a schematic enlarged cross-sectional view of the vicinity of a valve body and a valve seat in a pressure reducing valve of a second embodiment. FIG. 11 is a schematic enlarged cross-sectional view of the vicinity of a valve body and a valve seat in a pressure reducing valve of a third embodiment.

First Embodiment
Hereinafter, a first embodiment of a pressure reducing valve will be described with reference to the drawings.
1 is provided, for example, in the middle of a fluid circuit connecting a gas tank 2 of hydrogen gas mounted on a fuel cell vehicle and a fuel cell 3. The pressure reducing valve 1 reduces the pressure of hydrogen gas supplied from the gas tank 2 via a primary port 4 (hereinafter referred to as the primary pressure) to a predetermined pressure or lower, and sends the hydrogen gas to the fuel cell 3 via a secondary port 5. The primary pressure supplied from the primary port 4 is, for example, a high pressure of about 87.5 MPa. The predetermined pressure, which is the target value of the pressure reduced by the pressure reducing valve 1 (hereinafter referred to as the secondary pressure), is, for example, about 1.2 MPa.

The pressure reducing valve 1 includes a body 11, a valve seat 12, a valve body 13, a biasing member 14, and a first seal member 15 and a second seal member 16 which are movable seal members.
The body 11 has a gas flow passage 17 that communicates with the primary port 4 and the secondary port 5 and through which high-pressure gas flows. The valve seat 12 is disposed in the gas flow passage 17. The valve element 13 is disposed downstream of the valve seat 12 in the gas flow passage 17. The biasing member 14 biases the valve element 13 in a valve opening direction that separates the valve element 13 from the valve seat 12. The first seal member 15 and the second seal member 16 are each attached to the outer circumferential surface of the valve element 13. The valve element 13 moves toward and away from the valve seat 12 depending on the pressure difference between the primary pressure and the secondary pressure and the biasing force of the biasing member 14. The opening degree of the pressure reducing valve 1 changes depending on the position of the valve element 13, thereby adjusting the secondary pressure to be equal to or lower than a predetermined pressure.

More specifically, the body 11 includes a coupling member 21, a first housing member 22, and a second housing member 23. The coupling member 21, the first housing member 22, and the second housing member 23 are each made of metal. The body 11 is assembled by connecting the coupling member 21, the first housing member 22, and the second housing member 23 in this order from the upstream side in the flow direction of hydrogen gas. In the assembled body 11, the coupling member 21, the first housing member 22, and the second housing member 23 are each arranged on a common axis L.

The shape of the coupling member 21 is generally cylindrical with a step. The outer peripheral surface of the large diameter portion 31 of the coupling member 21 has a male thread. The coupling member 21 has a coupling flow path 32 that is part of the gas flow path 17. The coupling flow path 32 extends linearly along the axis L and opens at both ends of the coupling member 21. The upstream opening of the coupling flow path 32 functions as the primary port 4. In the illustrated example, the coupling member 21 has a filter 33 arranged at the downstream opening of the coupling flow path 32.

The first housing member 22 is generally cylindrical in shape. The outer diameter of the first housing member 22 is larger than the outer diameter of the coupling member 21. The first housing member 22 has a first mounting hole 41 and a second mounting hole 42 that are part of the gas flow path 17.

The first mounting hole 41 and the second mounting hole 42 are each round. The first mounting hole 41 opens to the end face facing the coupling member 21, i.e., the upstream side of the first housing member 22. The second mounting hole 42 is continuous with the downstream side of the first mounting hole 41. The first mounting hole 41 and the second mounting hole 42 are each provided on the same axis L. The inner peripheral surface of the first mounting hole 41 has a female thread. The coupling member 21 is connected to the first housing member 22 by screwing the large diameter portion 31 into the first mounting hole 41. The inner diameter of the second mounting hole 42 is smaller than the inner diameter of the first mounting hole 41. The valve seat 12 is attached to the second mounting hole 42. As a result, the valve seat 12 is positioned in the middle of the gas flow path 17. The position of the second mounting hole 42 in the first housing member 22 is the mounting position of the valve seat 12 in the body 11.

The first housing member 22 also has an accommodation hole 43 that is part of the gas flow path 17. The accommodation hole 43 is continuous with the second mounting hole 42 and opens to the end face of the first housing member 22 that faces the second housing member 23, i.e., the downstream side of the first housing member 22. The accommodation hole 43 is provided on the axis L. A part of the valve body 13 is accommodated in the accommodation hole 43. As a result, the valve body 13 is positioned downstream of the valve seat 12 in the gas flow path 17.

1 and 2, the accommodation hole 43 is generally circular. The first housing member 22 has a throttling portion 44 that gradually reduces the inner diameter of the upstream portion of the accommodation hole 43 toward the upstream side. The throttling portion 44 is formed as part of the first housing member 22 (integral with the first housing member 22). The throttling portion 44 has an annular flat surface on its inner periphery (downstream end) that is approximately perpendicular to the axis L. As described below, the inner periphery of the throttling portion 44, and in particular the flat surface, corresponds to a stopper 45.

1, the first housing member 22 has an installation groove 46 located on the outer periphery of the accommodation hole 43. The installation groove 46 is annular groove-shaped. The installation groove 46 is defined by a cylindrical peripheral wall 47 and is provided on the outer periphery of the accommodation hole 43. The installation groove 46 opens on the downstream side of the first housing member 22, like the accommodation hole 43. The outer wall portion 48 that defines the outer periphery of the installation groove 46 protrudes downstream from the peripheral wall 47. The outer wall portion 48 is cylindrical in shape. The outer peripheral surface of the first housing member 22 (outer wall portion 48) has a male thread at a position corresponding to the installation groove 46. In the illustrated example, the first housing member 22 has a communication passage 49 that communicates between the inside of the installation groove 46 and the outside of the body 11.

The second housing member 23 is generally cylindrical in shape. The outer diameter of the second housing member 23 is slightly larger than the outer diameter of the first housing member 22. The second housing member 23 has a connecting hole 51 that opens on the end face facing the first housing member 22, i.e., on the upstream side of the second housing member 23. The connecting hole 51 is circular in shape. The inner peripheral surface of the connecting hole 51 has a female thread at a position near the open end. The outer wall portion 48 is inserted into the back side of the connecting hole 51 and the outer peripheral surface of the first housing member 22 is screwed, thereby connecting the first housing member 22 to the second housing member 23. A third seal member 52, such as an O-ring, which is a fixed part seal member, is attached to the outer peripheral surface of the outer wall portion 48.

The second housing member 23 also has a housing flow passage 53 which is part of the gas flow passage 17. The housing flow passage 53 extends linearly along the axis L. The housing flow passage 53 has an upstream opening on the bottom surface of the connecting hole 51, and a downstream opening on the side of the second housing member 23 opposite the first housing member 22, i.e., on the downstream end surface of the second housing member 23. The downstream opening of the housing flow passage 53 functions as the secondary port 5.

The valve seat 12 is made of resin. The valve seat 12 is annular in shape. The valve seat 12 is disposed in the second mounting hole 42 of the first housing member 22. The valve seat 12 is pressed against the bottom surface of the second mounting hole 42 by the coupling member 21 attached to the first mounting hole 41. The valve seat 12 has a valve hole 61. The valve hole 61 extends linearly along the axis L and opens at both ends of the valve seat 12. The inner peripheral surface of the valve hole 61 is inclined in the downstream region of the valve hole 61 so that the inner diameter increases toward the downstream side.

The valve body 13 is made of metal. As shown in FIG. 2, the valve body 13 has a head 71, a main body 72, and a pressure-receiving portion 73. The head 71, the main body 72, and the pressure-receiving portion 73 are integrally formed in this order from the upstream side. The head 71 and the main body 72 are accommodated in the accommodation hole 43 of the first housing member 22, and the pressure-receiving portion 73 protrudes downstream from the peripheral wall 47 and is accommodated inside the outer wall portion 48. The valve body 13 is movable along the axis L within the body 11. In other words, the valve body 13 is capable of approaching and separating from the valve seat 12.

The head 71 is generally cylindrical in shape. The head 71 has a tapered shape that tapers toward the tip, i.e., the upstream side. The tapered shape of the head 71 is inclined to correspond to the inclination of the downstream region of the valve hole 61.

The shape of the main body 72 is generally cylindrical with a step. The main body 72 has a tip portion 81, an intermediate portion 82, and a base portion 83. The tip portion 81, the intermediate portion 82, and the base portion 83 are integrally formed in this order from the upstream side. The head portion 71 is provided on the upstream end surface of the tip portion 81. The outer diameter of the main body 72 increases in the order of the tip portion 81, the intermediate portion 82, and the base portion 83. The outer peripheral surface of the base portion 83 has a first mounting groove 84. The first mounting groove 84 extends in an annular shape around the entire circumference of the base portion 83.

The outer diameter of the tip portion 81 is smaller than the inner diameter of the throttling portion 44 of the first housing member 22, i.e., the stopper 45, and the gap between the tip portion 81 and the throttling portion 44 becomes part of the gas flow path 17. The outer diameter of the intermediate portion 82 is larger than the outer diameter of the tip portion 81 and the inner diameter of the stopper 45. The outer diameter of the base end portion 83 is slightly smaller than the inner diameter of the accommodation hole 43 and is made slidable. Therefore, the intermediate portion 82 cannot enter the stopper 45, and the outer periphery (upstream end) of the intermediate portion 82 abuts against the stopper 45. The intermediate portion 82 has an annular flat surface on its outer periphery that is approximately perpendicular to the axis L. In other words, the outer periphery of the intermediate portion 82, particularly the flat surface, corresponds to the abutment portion 85.

The relative position (distance) between the abutment portion 85 and the head portion 71, and the relative position (distance) between the mounting position of the valve seat 12 and the stopper 45 are set to satisfy the following conditions (a) and (b).

(a) The contact portion 85 does not contact the stopper 45 until the head portion 71 is firmly seated against the valve seat 12 and can block the flow of high-pressure hydrogen gas.
(b) Before the valve seat 12 is pressed by the valve body 13 and is excessively deformed, the contact portion 85 contacts the stopper 45 .

The main body 72 also has a plurality of horizontal holes 86 and one vertical hole 87. Each horizontal hole 86 extends linearly along a direction perpendicular to the axis L. Each horizontal hole 86 opens on the outer peripheral surface of the intermediate portion 82. The multiple horizontal holes 86 are provided at equal angular intervals in the circumferential direction of the main body 72. Since each horizontal hole 86 opens on the outer peripheral surface of the intermediate portion 82 in this manner, the abutment portion 85 is provided closer to the head 71 than each horizontal hole 86. The vertical hole 87 extends linearly along the axis L. The vertical hole 87 opens on the end face of the main body 72 opposite to the side where the head 71 is located. In other words, the downstream end of the vertical hole 87 opens on the downstream side of the valve body 13 in the gas flow path 17. On the other hand, the upstream end of the vertical hole 87 communicates with each of the multiple horizontal holes 86.

The pressure receiving portion 73 is generally stepped and annular. The pressure receiving portion 73 extends radially outward from the downstream end of the main body portion 72. The outer diameter of the pressure receiving portion 73 is slightly smaller than the inner diameter of the outer wall portion 48 of the first housing member 22, allowing it to slide. The thickness of the pressure receiving portion 73 along the axis L is thicker at the radially outer portion than at the radially inner portion. The outer peripheral surface of the pressure receiving portion 73 has a second mounting groove 88. The second mounting groove 88 extends annularly around the entire circumference of the pressure receiving portion 73.

A coil spring is used for the biasing member 14. The biasing member 14 is housed in the installation groove 46. The biasing member 14 is compressed in the installation groove 46 along the axis L between the bottom surface of the installation groove 46 and the pressure-receiving portion 73 of the valve body 13. As a result, the biasing member 14 biases the valve body 13 in the valve opening direction, i.e., downstream in the flow direction of hydrogen gas.

A lip seal is used for each of the first seal member 15 and the second seal member 16. The first seal member 15 is attached to the first mounting groove 84, and the second seal member 16 is attached to the second mounting groove 88. In other words, the first seal member 15 corresponds to the tip seal member that is provided closest to the head 71 among the seal members that are attached to the outer circumferential surface of the valve body 13. As described above, since the first mounting groove 84 is provided at the base end 83 of the main body 72, the abutment portion 85 provided at the intermediate portion 82 is provided at a position closer to the head 71 than the first seal member 15 (tip seal member).

The first seal member 15 seals between the outer peripheral surface of the main body 72 and the inner peripheral surface of the accommodation hole 43. The second seal member 16 seals between the outer peripheral surface of the pressure-receiving portion 73 and the inner peripheral surface of the outer wall portion 48. This prevents the reduced pressure hydrogen gas from being released to the outside through the installation groove 46 and the communication passage 49.

Next, the operation of the pressure reducing valve 1 will be described.
In the initial state before high pressure hydrogen gas is supplied from the primary port 4, the valve element 13 moves downstream due to the biasing force of the biasing member 14. As a result, the valve element 13 moves away from the valve seat 12, and the pressure reducing valve 1 is in an open state.

Hydrogen gas at primary pressure supplied from the primary port 4 passes through the joint flow path 32, which is the gas flow path 17, and flows into the accommodation hole 43 through the gap between the valve hole 61 and the head 71 of the valve body 13. When the hydrogen gas passes through the gap between the valve hole 61 and the head 71, the pressure is reduced according to the size of the gap. The reduced pressure hydrogen gas flows into the housing flow path 53, which is the gas flow path 17, through the horizontal hole 86 and the vertical hole 87, and is sent out from the secondary port 5. As the amount of hydrogen gas flowing in through the valve hole 61 increases in this way, the secondary pressure rises.

The valve body 13 is biased downstream (in the valve opening direction) by the biasing force of the biasing member 14 and by a biasing force corresponding to the primary pressure received by the head 71 through the valve hole 61. In contrast, the valve body 13 is biased upstream (in the valve closing direction) by a biasing force corresponding to the secondary pressure received mainly by the pressure receiving portion 73. The valve body 13 moves depending on the magnitude relationship between the biasing force toward the upstream side and the biasing force toward the downstream side.

The valve element 13 approaches the valve seat 12 as the secondary pressure increases, and seats on the valve seat 12 when the secondary pressure reaches a predetermined pressure. In other words, the pressure reducing valve 1 is in a closed state. In this embodiment, when the valve element 13 is firmly seated on the valve seat so as to block the inflow of hydrogen gas from the primary port 4, and is biased by a biasing force according to the secondary pressure, and attempts to move further toward the valve seat 12, the abutment portion 85 abuts against the stopper 45. This restricts the valve element 13 from moving upstream.

After that, when hydrogen gas is consumed in the fuel cell 3 and the secondary pressure drops, the valve body 13 moves downstream. This opens the pressure reducing valve 1 and hydrogen gas flows in from the primary port 4. In this way, the valve body 13 moves according to the pressure difference between the primary and secondary pressures, and hydrogen gas at a predetermined pressure is discharged from the pressure reducing valve 1.

Next, the operation and effects of this embodiment will be described.
(1) The valve element 13 has a contact portion 85. The body 11 has a stopper 45 that restricts the upstream movement of the valve element 13 by contacting the contact portion 85. Therefore, the upstream movement of the valve element 13 is restricted by the contact portion 85 contacting the stopper 45, so that excessive deformation of the valve seat 12 can be suppressed, and thus a reduction in the life of the valve seat 12 can be suppressed.

Here, from the viewpoint of not deforming the valve seat 12 excessively, it is desirable that the abutment portion 85 abuts against the stopper 45 as soon as possible when the valve body 13 moves upstream. On the other hand, from the viewpoint of appropriately reducing the pressure of the high-pressure hydrogen gas, it is desirable to not restrict the movement of the valve body 13 upstream as much as possible so that the valve body 13 can be firmly seated on the valve seat 12 and block the flow of hydrogen gas when the pressure reducing valve 1 is closed. Therefore, in order to seat the valve body 13 firmly against the valve seat 12 while suppressing excessive deformation of the valve seat 12, it is necessary to precisely define the position at which the movement of the valve body 13 upstream is restricted and to prevent variation for each individual manufactured. To achieve this, it is required to increase the dimensional accuracy of the valve body 13 and the body 11 as much as possible. Specifically, it is necessary to reduce the variation in the relative position between the head 71 and the abutment portion 85, and the relative position between the mounting position of the valve seat 12 and the stopper 45. However, for example, dimensional tolerances are set when manufacturing the valve body 13 and body 11, so there is a limit to how high the dimensional precision of the entire part can be.

In this respect, in the present embodiment, the abutment portion 85 is provided at a position closer to the head 71 than the lateral hole 86 in the valve body 13. In other words, the abutment portion 85 is provided at a position preferably close to the head 71. Therefore, compared to a case in which the abutment portion 85 is provided at a position away from the head 71, the variation in the relative position between the head 71 and the abutment portion 85 can be preferably reduced. In addition, the stopper 45 is provided at a position preferably close to the mounting position of the valve seat 12 in correspondence with the head 71 and the abutment portion 85. Therefore, the variation in the relative position between the mounting position of the valve seat 12 and the stopper 45 can be preferably reduced. This makes it possible to appropriately regulate the secondary pressure while suppressing excessive deformation of the valve seat 12.

(2) The stopper 45 is formed as part of the body 11 (integrally with the body 11). Therefore, the variation in the relative position between the mounting position of the valve seat 12 and the stopper 45 can be reduced compared to when the stopper 45 is formed separately from the body 11.

(3) The abutment portion 85 is formed as part of the valve body 13 (integrally with the valve body 13). Therefore, the variation in the relative position between the head 71 and the abutment portion 85 can be reduced compared to when the abutment portion 85 is formed separately from the valve body 13.

Second Embodiment
Next, a pressure reducing valve according to a second embodiment will be described with reference to the drawings. For the sake of convenience, the same components as those in the first embodiment will be denoted by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 3, the shape of the accommodation hole 43 in this embodiment is a stepped circular hole. The accommodation hole 43 has a downstream large diameter hole portion 91 and a small diameter hole portion 92 that continues to the upstream side of the large diameter hole portion 91. The large diameter hole portion 91 is slightly larger than the outer diameter of the base end portion 83 of the valve body 13, allowing the valve body 13 to slide. The small diameter hole portion 92 is smaller than the outer diameter of the base end portion 83 and larger than the outer diameter of the intermediate portion 82. The stopper 93 is formed as a part of the first housing member 22 in the step portion between the large diameter hole portion 91 and the small diameter hole portion 92 in the first housing member 22.

As described above, the outer diameter of the base end 83 is larger than the inner diameter of the small diameter hole 92. Therefore, when the valve body 13 moves further toward the valve seat 12 from the state where it is seated on the valve seat 12, the outer peripheral edge of the base end 83 abuts against the stopper 93. The base end 83 has an annular flat surface on its outer peripheral edge that is approximately perpendicular to the axis L. In other words, the outer peripheral edge of the base end 83, particularly the flat surface, corresponds to the abutment portion 94. As described above, since the abutment portion 94 is the outer peripheral edge of the base end 83, it is located farther from the head 71 than the side hole 86, but is located closer to the head 71 than the first seal member 15. The relative positions of the abutment portion 94 and the head 71, and the relative positions of the mounting position of the valve seat 12 and the stopper 93 are set to satisfy the above conditions (a) and (b).

As described above, in addition to the same effects and advantages as those of (2) and (3) of the first embodiment, the present embodiment provides the following effects and advantages.
(4) The abutment portion 94 is provided at a position on the valve body 13 closer to the head 71 than the first seal member 15. In other words, the abutment portion 94 is provided at a position close to the head 71. Therefore, it is possible to reduce variation in the relative position between the head 71 and the abutment portion 94 compared to a case in which the abutment portion 94 is provided at a position away from the head 71. Furthermore, the stopper 93 is provided at a position close to the attachment position of the valve seat 12 in correspondence with the head 71 and the abutment portion 94. Therefore, it is possible to reduce variation in the relative position between the attachment position of the valve seat 12 and the stopper 93.

(5) The abutment portion 94 is located farther from the head 71 than the lateral hole 86. Therefore, when the abutment portion 94 abuts against the stopper 93, the force acting from the stopper 93 on the abutment portion 94 is less likely to affect the intermediate portion 82 located upstream of the base end portion 83. This makes it possible to prevent the lateral hole 86 from deforming even if the abutment portion 94 repeatedly abuts against the stopper 93.

Third Embodiment
Next, a third embodiment of the pressure reducing valve will be described with reference to the drawings. For convenience of explanation, the same components as those in the first embodiment are denoted by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 4, the first housing member 22 has a third mounting hole 101 that is part of the gas flow path 17. The third mounting hole 101 is continuous with the downstream side of the second mounting hole 42. The third mounting hole 101 is circular in shape. The third mounting hole 101 is provided on the axis L. The inner diameter of the third mounting hole 101 is smaller than the inner diameter of the second mounting hole 42 and larger than the inner diameter of the inner peripheral edge of the constriction portion 44.

The body 11 is provided with a metal stopper 102. The stopper 102 is formed separately from the first housing member 22. The stopper 102 is attached to the third mounting hole 101. In other words, the stopper 102 is disposed adjacent to the valve seat 12 and downstream of the valve seat 12.

The stopper 102 has a circular ring shape. The stopper 102 has a through hole 103. The through hole 103 extends linearly along the axis L and opens at both ends of the stopper 102. The inner diameter of the through hole 103 is smaller than the inner diameter of the throttling portion 44 and larger than the outer diameter of the head 71. When the stopper 102 is placed in the third mounting hole 101, the entire upstream end face of the stopper 102 contacts the valve seat 12. The stopper 102 has an inner and outer diameter larger than the head 71 of the valve body 13, and the contact area of the valve seat 12 with the stopper 102 is larger than the contact area of the valve seat 12 with the head 71.

The outer diameter of the tip 81 of the valve body 13 is smaller than the inner diameter of the throttling portion 44, and the gap between the tip 81 and the throttling portion 44 forms part of the gas flow path 17. The outer diameter of the tip 81 of the valve body 13 is larger than the inner diameter of the stopper 102. Therefore, when the valve body 13 moves further toward the valve seat 12 from the state where it is seated on the valve seat 12, the outer periphery of the tip 81 abuts against the stopper 102. The tip 81 has an annular flat surface on its outer periphery that is approximately perpendicular to the axis L. In other words, the outer periphery of the tip 81, particularly the flat surface, corresponds to the abutment portion 104. The relative positions of the abutment portion 104 and the head 71, and the relative positions of the mounting position of the valve seat 12 and the stopper 102 are set to satisfy the above conditions (a) and (b).

As described above, in addition to the same effects and advantages as those of (1) and (3) of the first embodiment, the present embodiment provides the following effects and advantages.
(6) The stopper 102, which is formed separately from the body 11, is disposed adjacent to the valve seat 12 and downstream of the valve seat 12. As a result, when the valve is closed, the stopper 102 is sandwiched between the valve seat 12 and the valve body 13. Therefore, the impact when the abutting portion 104 abuts against the stopper 102 is absorbed by the valve seat 12, and the hitting sound when the abutting portion 104 abuts against the stopper 102 can be reduced.

(7) The contact area of the valve seat 12 with the stopper 102 is larger than the contact area of the valve seat 12 with the head 71. Therefore, the valve seat 12 can be prevented from being excessively deformed by the biasing force of the valve body 13 received through the stopper 102.

The above-described embodiments may be modified as follows: The above-described embodiments and the following modifications may be combined with each other to the extent that no technical contradiction occurs.
In the third embodiment, the contact area of the valve seat 12 with the stopper 102 may be set to be equal to or smaller than the contact area of the valve seat 12 with the head 71 .

In the third embodiment, the stopper 102 may be made of, for example, resin.
In the first and second embodiments, the stoppers 45, 93 may be formed separately from the first housing member 22. In this case, the stoppers may be made of, for example, resin.

In each of the above-described embodiments, the contact portions 85, 94, 104 may be formed separately from the valve body 13. In this case, the contact portions may be made of, for example, resin.
In the above embodiment, the pressure reducing valve 1 includes two seal members, the first seal member 15 and the second seal member 16, but the present invention is not limited to this and may include a single seal member or three or more seal members. The seal member is not limited to a lip seal, and may be, for example, an O-ring. Furthermore, the seal member may include, for example, a backup ring in addition to the lip seal or the O-ring.

In each of the above-described embodiments, the number and arrangement of the lateral holes 86 may be changed as appropriate.
In each of the above embodiments, a coil spring is used as the biasing member 14. However, the present invention is not limited to this and other elastic members, such as a disc spring, may be used.

- In each of the above embodiments, the pressure reducing valve 1 is used to reduce the pressure of high-pressure hydrogen gas, but it may also be used to reduce the pressure of high-pressure gases other than hydrogen.

REFERENCE SIGNS LIST 1... Pressure reducing valve 11... Body 12... Valve seat 13... Valve body 14... Pressurizing member 15... First seal member (seal member, tip seal member)
16...Second seal member (seal member)
17: Gas flow passage 45, 93, 102: Stopper 71: Head portion 85, 94, 104: Contact portion

Claims (6)

a body having a gas flow passage;
a valve seat disposed in the gas flow path;
a valve body that is disposed downstream of the valve seat in the gas flow path and moves toward and away from the valve seat;
a biasing member that biases the valve body in a direction away from the valve seat;
At least one seal member attached to an outer circumferential surface of the valve body,
The valve body is
a head portion capable of being seated on the valve seat;
a contact portion located closer to the head than a tip seal member provided at a position closest to the head among the at least one seal member,
The body includes a stopper that restricts upstream movement of the valve element by abutting against the abutment portion. 2. The pressure reducing valve according to claim 1,
the valve body further includes a main body having a lateral hole that opens at a position in the valve body closer to the head than the tip seal member, and a vertical hole that communicates with the lateral hole and communicates with a downstream side of the valve body in the gas flow path,
The abutment portion is provided at a position closer to the head than the lateral hole in the valve body. 2. The pressure reducing valve according to claim 1,
the valve body further includes a main body having a lateral hole that opens at a position in the valve body closer to the head than the tip seal member, and a vertical hole that communicates with the lateral hole and communicates with a downstream side of the valve body in the gas flow path,
The abutment portion is provided at a position farther from the head portion than the lateral hole in the valve body. The pressure reducing valve according to any one of claims 1 to 3,
The stopper is a pressure reducing valve formed as part of the body. The pressure reducing valve according to any one of claims 1 to 3,
The stopper is formed separately from the body, and is disposed adjacent to the valve seat downstream of the valve seat. 6. The pressure reducing valve according to claim 5,
A pressure reducing valve, wherein the contact area of the valve seat with the stopper is larger than the contact area of the valve seat with the head.