JP2010025229A - Gas control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve device capable of exhibiting high performance over a long period time. <P>SOLUTION: This gas control device includes a cover 25 dividing a lead-in flow passage 261 for leading a high-pressure gas into a pressure receiving space C and a lead-out flow passage 112 for leading the high-pressure gas from the inside of the pressure receiving space C, a piston 22 which is disposed in the cover 25 and has a pressure receiving surface 22a, and a seal member 222 interposed between the piston 22 and the cover 25. The pressure receiving surface 22a has, at the periphery, a slope 22a1 diagonally projecting from the piston 22 outwardly. The flow of the high-pressure gas can be appropriated by forming the slope on the pressure receiving surface. Even if a foreign matter is mixed in the flow of the high-pressure gas, the lead-in high-pressure gas flows along the slope, and bent in the direction away from the pressure receiving surface. Consequently, a possibility that the flow of the high-pressure gas flows between the piston and a cylinder space without being disturbed, and the foreign matter involved into a seal member can be reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a gas control device such as a valve device, and more particularly to a gas control device suitable for a pressure reducing valve for reducing a high pressure gas such as hydrogen gas to a target pressure.

  The plug that closes the opening of the gas tank that stores the high-pressure fluid has one or more flow paths that connect the inside and the outside of the gas tank, and a valve device that controls the flow of gas in the flow path is provided. ing. As an example of the valve device, there is a pressure reducing valve that controls the pressure of gas led out to the outside (Patent Documents 1 and 2, etc.).

  The pressure reducing valve is a valve that supplies high pressure gas after reducing the pressure to a predetermined pressure. For example, there is a pressure reducing valve having a configuration as shown in FIG. This pressure reducing valve has a valve mechanism 910 and a pressure regulating mechanism 920. The valve mechanism 910 includes a body 911, a poppet 912, a seat 913, and other members. The pressure adjusting mechanism 920 includes a pin 921, a pressure adjusting piston 922, a spring 923, a pressure adjusting screw 924, a cover 925, and other members.

The valve mechanism 910 is opened and closed by the pressure adjusting mechanism 920 to adjust the pressure. Specifically, the poppet 912 is moved in conjunction with the piston 922 that moves in accordance with the pressure in the secondary chamber (pressure receiving space) C defined by the cover 925 and the piston 922 of the pressure adjusting mechanism 920 to move the valve mechanism 910. By opening and closing, the valve mechanism 910 is opened and closed so that the pressure in the pressure receiving space C becomes a predetermined pressure. A sealing member is interposed between the piston and the cover of the pressure adjusting mechanism in order to ensure sealing performance (Patent Document 2).
JP 2007-271075 A JP 2006-185103 A

  By the way, it is not preferable to mix even a very small foreign substance such as dust in the high-pressure gas flow. For example, if the mixed foreign matter is caught in the sealing member, the sealing member may not be able to exhibit sufficient sealing performance. Therefore, measures are required to prevent the entry of foreign matter and prevent foreign matter from being caught in the seal member.

  Further, there are cases where the pressure in the pressure receiving space C is low, such as when the pressure reducing valve is first operated to derive the gas in the gas tank. In this case, when the pressure reducing valve is operated, the high pressure gas suddenly flows into the pressure receiving space C, so that a sudden force is also applied to the seal member 9222 interposed between the piston 922 and the cover 925. In that case, the position of the seal member 9222 may be shifted and the original performance may not be exhibited.

  This invention is completed in view of the said situation, and makes it the subject which should be solved to provide the valve apparatus which can exhibit high performance over a long period of time.

The feature of the gas control device according to claim 1 that solves the above-described problem is that a cylindrical cylinder space, an introduction flow path for introducing high-pressure gas into the cylinder space, and a derived flow for deriving the high-pressure gas from the cylinder space. A cylinder member that partitions the road;
A piston having a pressure receiving surface, which is provided in the cylinder space so as to be movable in the axial direction of the cylinder space, and partitions a part of the cylinder space as a pressure receiving space together with the inner surface of the cylinder space;
A seal member interposed between the outer periphery of the piston and the inner surface of the cylinder space,
The pressure receiving surface of the piston has an inclined portion that inclines in a direction protruding from the piston as at least a part of a peripheral portion close to the inner surface of the cylinder space goes outward.

  A feature of a gas control device according to a second aspect of the present invention for solving the above-mentioned problem is that, in the first aspect, the introduction flow path opens to face the pressure receiving surface.

  A feature of the gas control device according to claim 3 that solves the above-mentioned problem is that, in claim 1 or 2, the inclined portion is formed over the entire circumference of the peripheral portion.

  A feature of the gas control device according to claim 4 that solves the above-described problem is that, in any one of claims 1 to 3, an elastic member that urges the piston in a direction to reduce the pressure receiving space, and the pressure receiving space. The inlet passage is opened and closed according to the position in the axial direction of the piston so as to open when the internal pressure becomes less than the first predetermined pressure and close when the pressure exceeds the second predetermined pressure. And a valve device connected to the upstream side.

  In the first aspect of the present invention, the pressure receiving surface is formed with an inclined portion that protrudes toward the outside, whereby the flow of the high pressure gas can be optimized, and the flow of the high pressure gas remains on the seal member as it is. Can be prevented. For this reason, even if foreign matter is mixed into the flow of the high-pressure gas, the possibility of being caught up without reaching the seal member is reduced. That is, when the high pressure gas is introduced into the pressure receiving space, when the high pressure gas introduced from the introduction flow path reaches the pressure receiving surface and then flows along the pressure receiving surface, a part of the pressure receiving surface is directed outward. Since the inclined portion is made to protrude along with the high pressure gas, the high pressure gas flows along the inclined portion, and the flow of the high pressure gas is bent in a direction away from the pressure receiving surface. For this reason, it is possible to reduce the possibility that the high-pressure gas accompanied by the foreign substance flows between the piston and the cylinder space as it is and the foreign substance is caught in the seal member. Moreover, the possibility that the seal member is displaced due to the momentum of the flow of the high-pressure gas can be reduced.

  In the invention according to claim 2, since the flow of the high-pressure gas introduced from the introduction flow channel once hits the surface of the pressure receiving surface by opening the introduction flow channel facing the pressure receiving surface, It becomes easy to flow along the surface of the pressure receiving surface, and the flow of the high pressure gas can be controlled along the shape of the pressure receiving surface (particularly the inclined portion).

  In the invention which concerns on Claim 3, it can prevent effectively that a high voltage | pressure gas penetrate | invade between a piston and cylinder space vigorously by providing an inclined part over the perimeter of a pressure receiving surface.

  In the invention which concerns on Claim 4, it becomes possible by using the said structure to control the pressure of the high pressure gas in a pressure receiving space with high precision.

  Hereinafter, an embodiment in which the valve device of the present invention is embodied as a pressure reducing valve for reducing the hydrogen gas to a predetermined pressure in a hydrogen gas tank that stores hydrogen gas as a high-pressure gas having a pressure of 35 MPa or more will be described with reference to the drawings. . The gas control device of the present invention is mainly employed as a pressure regulating mechanism for a pressure reducing valve.

(Constitution)
As shown in FIG. 1, the pressure reducing valve of the present embodiment is a valve that reduces the high-pressure hydrogen gas introduced in the A direction to the flow path 111 to a desired pressure and leads the B flow direction from the outlet flow path 112 to the B direction. It is. The channel 111 is connected to a gas outlet (not shown) of a high-pressure hydrogen tank (not shown) for storing high-pressure hydrogen gas, and the outlet channel 112 is a hydrogen supply for an apparatus (not shown) that needs to supply hydrogen. Connected to the mouth (not shown).

  The pressure reducing valve of this embodiment includes a valve mechanism 10 and a pressure adjusting mechanism 20.

  The valve mechanism 10 has a body 11, a poppet 12, a seat 13, and other members. The pressure adjusting mechanism 20 includes a pin 21, a pressure adjusting piston 22 (corresponding to a piston), a spring 23, a pressure adjusting screw 24, a cover 25 (corresponding to a cylinder member), and other members.

(Valve mechanism 10)
The poppet 12 is a columnar object having a substantially conical shape with a part of the tip thereof tapered. The valve mechanism 10 is opened and closed when the outer peripheral surface of the substantially conical portion at the front end is separated from the hole formed in the seat 13. A columnar member having a flat tip is provided at the tip of the substantially conical portion at the tip of the poppet 12. A hole through which the columnar member at the tip can be inserted through a certain gap is provided in the sheet 13. When the columnar member at the tip is pushed in the axial direction, the poppet 12 moves in the axial direction. The columnar member at the tip is pressed by the pin 21 of the pressure adjusting mechanism 20. That is, the poppet 12 opens and closes the valve mechanism 10 by being appropriately pressed by the pin 21, and as a result, controls the pressure of the hydrogen gas flowing out.

  Inside the poppet 12 is formed a spring accommodating portion that is a columnar cavity that opens in a direction opposite to the substantially conical portion. A spring 14 for urging the poppet 12 on one end side toward the substantially conical portion is disposed in the spring housing portion. The biasing force of the spring 14 is set to a value sufficiently smaller than the biasing force of the spring 23 described later. The other end side of the spring 14 is pressed by a pressing member 16. The holding member 16 has a loosely fitting portion that is loosely fitted from one end side to a spring housing portion formed at one end portion of the poppet 12. The other end side of the loose fitting portion has a stepped portion that restricts the opening of the poppet 12 so that it cannot be further advanced and the loose fitting portion cannot be inserted into the spring accommodating portion of the poppet 12 any more. The stepped portion limits the movement distance of the poppet 12 in the axial direction. The poppet 12 is disposed in a cylindrical space 11a provided in the body 11 together with a guide member 15 in which a guide space movable in the axial direction is formed. The guide space is a hole that penetrates the guide member 15. The opening diameter of the guide space is a size that allows the poppet 12 to pass therethrough with almost no gap except for one end. One end portion of the guide space is an end portion on the side corresponding to the substantially conical portion of the poppet 12 and is reduced in diameter so that the poppet 12 cannot pass through. A seal member 13 is fitted into the reduced diameter portion. A groove 121 extending in the axial direction is formed in the outer peripheral portion of the poppet 12 to form a gap that allows hydrogen gas to flow between the inner periphery of the guide space.

  In the body 11, a cylindrical cylindrical space 11a having one end opened is formed. An opening recess having a larger diameter is formed in the opening of the cylindrical space 11a. An outlet channel 112 is formed in an oblique direction on the bottom surface of the opening recess. The inner diameter of the outlet channel 112 is larger than the inner diameter of the channel 111 described later. The pressing member 16 and the guide member 15 are arranged in this order from the back in the cylindrical space 11a. A screw groove is formed in the inner surface of the cylindrical space 11a of the body 11 where the pressing member 16 and the guide member 15 are disposed, and the pressing member 16 and the guide member 15 having corresponding screw grooves formed on the outer periphery. Is inserted by screwing. A gap is formed between the pressing member 16 and the guide member 15 in the axial direction of the cylindrical space 11a of the body 11, and hydrogen gas is circulated through the gap. In the cylindrical space 11a of the body 11, a flow path 111 having one end opened at a position corresponding to the gap formed between the pressing member 16 and the guide member 15 described above is formed. The inner diameter of the flow path 111 is smaller than the inner diameter of the cylindrical space 11 a of the body 11. A seal member 151 that is an O-ring is interposed between the guide member 15 and the cylindrical space 11 a of the body 11. Since the seal member 151 is urged upward in the drawing in FIG. 1 by the pressure of hydrogen gas, backup rings 152 and 153 are arranged next to the seal member 151 (on the upper side in the drawing).

(Pressure adjusting mechanism 20)
The pin 21 is a columnar member whose tip is substantially conical. A columnar member having a flat tip is formed at the tip of the substantially conical portion of the pin 21. The diameter of the columnar member is approximately the same as the size of the columnar member formed at the tip of the poppet 12 described above, and the tip of the pin 21 presses the tip of the poppet 12. The pin 21 is inserted into a pin guide member 26 having a hole having the same diameter. A hole 261 (corresponding to an introduction channel) provided in the pin guide member 26 has a columnar shape with one end reduced in diameter. The degree of diameter reduction at one end is such that the tip of the pin 21 can be inserted. The hole 261 opens upward in the drawing.

  The pin guide member 26 is mounted on the guide member 15 with one end directed toward the guide member 15. A hole in which the pin guide member 26 can be mounted is formed in the guide member 15, and a screw groove that can be screwed is formed between the outer periphery of the pin guide member 26 and the hole of the guide member 15. The guide member 15 and the pin guide member 26 hold and fix the seal member 13. The pin 21 is movable in the axial direction within the pin guide member 26. When the pin 21 moves to the poppet 12 side, the poppet 12 is pressed in the axial direction, and the valve mechanism 10 is opened. On the other hand, the pin 21 moves in the direction opposite to the poppet 12 to release the pressure on the poppet 12. The outer peripheral portion of the pin 21 has a prismatic shape, and a gap is formed between the inner periphery of the hole 261 provided in the pin guide member 26. Hydrogen gas flows through this gap.

  The pin 21 is pressed by the piston 22 at the other end opposite to the tip. The pin 21 is sandwiched between the piston 22 and the poppet 12 and moves in the axial direction. The pin 21 is pressed by the tip protrusion 221 a of the piston 22. The tip protrusion 221 a is formed at a substantially central portion of the pressure receiving surface 22 a of the piston 22. The pressure receiving surface 22 a is a surface on the lower side of the piston 22 in the drawing, and is a surface facing the opening portion of the hole 261 formed in the pin guide member 26. The pressure receiving surface 22a will be described in detail later.

  The size of the tip protrusion 221a is determined such that the tip of the pin 21 presses the poppet 12 when the piston 22 abuts on the pin guide member 26 and the valve mechanism 10 is opened. The piston 22 has a piston main body 221, a seal member 222, a holder 223, and a sliding member 224. The seal member 222 is an O-ring that keeps airtightness between the cover 25 and is interposed between the piston 22 and the cover 25. The seal member 222 is held in a groove formed on the outer periphery of the piston 22 by the piston body 221 and the holder 223. The piston 22 can smoothly slide on the inner surface of the cover 25 by the sliding member 24. One end of the cover 25 has a large opening, and a spring 23 that biases the piston 22 in the opening direction is disposed. The cover 25 is fitted into the opening recess of the body 11 so that both openings are opposed to each other. The airtightness between the two is held by a seal member 251 interposed therebetween. One end of the spring 23 urges the piston 22 in the direction of the pin 21, and the other end abuts on a spring retainer 27 disposed in the cover 25. An adjustment screw 24 that presses the spring retainer 27 from the opposite direction to the side that contacts the spring 23 is disposed. The adjusting screw 24 is screwed into a screw hole provided on the opposite side of the cover 25 in the opening direction, and the position of the spring retainer 27 is adjusted by adjusting the degree of screwing. By displacing the position of the spring retainer 27, the degree of compression of the spring 23 can be adjusted, and the magnitude of the urging force that urges the piston 22 by the spring 23 can be adjusted. An opening valve 28 that can communicate with the inside and outside of the cover 25 as appropriate is provided.

(Pressure receiving surface 22a)
The pressure receiving surface 22 a of the piston 22 defines a pressure receiving space together with the inner peripheral surface of the cover 25. The pressure receiving surface 22a has an inclined portion 22a1. The inclined portion 22a1 is provided on the entire periphery of the peripheral portion of the pressure receiving surface 22a (FIG. 2A). The degree to which the inclined portion 22a1 is inclined is not particularly limited, and a slight protrusion is sufficient as long as it protrudes toward the outside of the pressure receiving surface 22a. For example, the left portion of the inclined portion 22a1 in FIG. 2B protrudes (downward in the drawing) toward the outside (left side in the drawing) of the pressure receiving surface 22a. The degree of inclination does not need to be uniform, and the surface of the inclined portion 22a1 may be a curved surface. In the present embodiment, the inclined portion 22a1 is formed as a part separate from the piston main body 221 as a part of the holder 223, but is not limited to this form, and may be provided in the piston main body 221. The piston main body 221 and the holder 223 may be formed over the piston main body 221 and the holder 223. Further, it is possible to divide the piston main body 221 and the holder 223 so as not to form the piston 22, and in this case, an inclined portion is formed on the pressure receiving surface of the integrally formed piston. Furthermore, it is not essential to provide the inclined portion 22a1 over the entire circumference of the peripheral portion of the pressure receiving surface 22a, and it is also possible to provide the inclined portion 22a1 in a part of the circumferential direction. Moreover, it can also be provided intermittently with respect to the circumferential direction. Since the effect can be exhibited without providing the inclined part so as to contact the edge of the pressure receiving surface, “providing the inclined part in the peripheral part” includes the case where the inclined part is provided with some space from the periphery.

(Function and effect)
Since the valve device of the present embodiment has the above-described configuration, the following operational effects are exhibited.

  First, the operation of the valve device will be described. Considering the case where hydrogen gas is introduced from the flow path 111 in the A direction, the introduced hydrogen gas reaches a portion where the sheet 13 is disposed along the groove 121 formed on the outer periphery of the poppet 12. Here, when the tip of the poppet 12 is in contact with the sheet 13, the hydrogen gas cannot further travel, and when the tip of the poppet 12 is separated from the sheet 13, the hydrogen gas Flows out from the outlet flow path 112 in the B direction through the seat 13, through the pressure receiving space C defined by the piston 22, the cover 25, and the opening recess of the body 11. When the high pressure gas flows in this manner, the inclined portion 22a1 is provided in the peripheral portion of the pressure receiving surface 22a, so that the flow of the high pressure gas can be made to flow along the inclined portion 22a1, and the flow of the high pressure gas is changed to the piston 22. It is possible to urge in the direction away from. As a result, it is possible to effectively prevent the high-pressure gas from entering the seal member 222 interposed between the piston 22 and the inner surface of the cover 25 as it is. That is, as shown in FIG. 2B, the flow of the high-pressure gas ejected toward the pressure receiving surface 22a flows outward along the pressure receiving surface 22a. FIG. 2B shows a part of the flow. As shown, the high-pressure gas is ejected toward the pressure receiving surface 22a, hits the vicinity of the center of the pressure receiving surface 22a, and then flows toward the periphery of the pressure receiving surface 22a. When the flow of the high-pressure gas reaches the inclined portion 22a1 of the pressure receiving surface 22a, it flows along the surface of the inclined portion 22a1, so that the high-pressure gas is urged in a direction away from the pressure receiving surface 22a and then hits the inner surface of the cover 25. It flows in a direction away from the piston 22 along the inner surface of the cover 25. Therefore, even if foreign matter is mixed into the flow of high-pressure gas, the foreign matter can be effectively prevented from entering between the piston 22 and the cover 25.

  Here, the momentum of the flow of the high-pressure gas is when the pressure in the pressure receiving space C is low (for example, when the pressure reducing valve is operated first, or when the pressure reducing valve is operated again after the hydrogen in the pressure receiving space C is used up). Especially large. When the flow of the high pressure gas reaches the periphery of the pressure receiving surface 22a, the high pressure gas is urged in a direction protruding from the pressure receiving surface 22a (a direction away from the pressure receiving surface 22a). It is possible to prevent the high pressure gas from strikingly striking the seal member 222 interposed therebetween.

  Next, a mechanism for the poppet 12 to be attached to and detached from the sheet 13 will be described. When the pressure in the pressure receiving space C decreases and becomes less than the first predetermined pressure, when the force applied to the piston 22 by the pressure in the pressure receiving space C becomes smaller than the urging force of the spring 23 against the piston 22, the piston 22 moves to the spring 23. It is displaced to the poppet 12 side by the urging force. Then, the tip of the poppet 12 is pressed by the piston 22 through the pin 21, and the poppet 12 is separated from the sheet 13. The pressure in the pressure receiving space C decreases due to the outflow of hydrogen gas from the outlet channel 112.

  On the contrary, when the pressure in the pressure receiving space C becomes higher and exceeds the second predetermined pressure, the force applied to the piston 22 by the pressure in the pressure receiving space C becomes larger than the urging force of the spring 23 to the piston 22. The spring 23 is displaced in a direction away from the poppet 12 against the urging force of the spring 23. Then, the force applied to the poppet 12 in the direction away from the sheet 13 is lost, and the poppet 12 comes into contact with the sheet 13 by the urging force of the spring 14. The pressure in the pressure receiving space C is improved when hydrogen gas flows into the pressure receiving space C from the flow path 111. The first predetermined pressure and the second predetermined pressure can be adjusted by the biasing force of the spring 23.

  Thus, the valve mechanism 10 is mechanically adjusted so that the pressure in the pressure receiving space C falls within a predetermined pressure range determined by the biasing force of the spring 23. Since the urging force of the spring 23 can be adjusted by the displacement of the spring retainer 27, the pressure in the pressure receiving space C can be set within a predetermined pressure range by adjusting the adjusting screw 24. That is, the pressure of the hydrogen gas led out from the lead-out flow path 112 connected to the pressure receiving space C can be adjusted within a certain range.

  As described above, by forming the inclined portion 22a1 in the peripheral portion of the pressure receiving surface 22a of the piston 22, it is possible to effectively prevent the flow of the high-pressure gas from entering the piston 22 and the cover 25 as it is. Therefore, even if foreign matter is included in the high-pressure gas, the foreign matter can be prevented from reaching the sealing member 222 and being caught. Further, it is possible to prevent the position of the seal member 222 from being shifted due to the high-pressure gas colliding with force.

(Modification)
The valve device of the present invention is essentially formed by forming an inclined portion in the periphery of the pressure receiving surface of the piston, and energizing the flow of the high-pressure gas in a direction away from the pressure receiving surface. The application range is not limited to the pressure regulating mechanism or the like. In the present embodiment, the pressure reducing valve is described as an example of the valve device, but the present invention can also be applied to other valves (such as electromagnetic valves).

It is a partial section schematic diagram of a valve device in an embodiment. It is the front view (a) of the pressure receiving surface of the piston of the valve apparatus in embodiment, and the partial cross section schematic diagram (b) of the pressure receiving surface vicinity of a piston. It is a partial cross-sectional schematic diagram of the valve apparatus in a prior art. It is a partial cross section schematic diagram of the pressure-receiving surface vicinity of the piston of the valve apparatus in a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Valve apparatus 11 ... Body 12 ... Poppet 13 ... Sheet 14 ... Spring 15 ... Guide member 111 ... Flow path 112 ... Derivation flow path 20 ... Pressure regulation mechanism 21 ... Pin 22 ... Piston 22a ... Pressure receiving surface 22a1 ... Inclination part 222 ... Seal member 23 ... Spring 24 ... Adjustment screw 25 ... Cover (cylinder member) 26 ... Pin guide member 27 ... Spring presser C ... Pressure receiving space

Claims (4)

A cylinder member that defines a cylindrical cylinder space, an introduction flow path for introducing high-pressure gas into the cylinder space, and a discharge flow path for deriving the high-pressure gas from the cylinder space;
A piston having a pressure receiving surface, which is provided in the cylinder space so as to be movable in the axial direction of the cylinder space, and partitions a part of the cylinder space as a pressure receiving space together with the inner surface of the cylinder space;
A seal member interposed between the outer periphery of the piston and the inner surface of the cylinder space,
The gas control device according to claim 1, wherein the pressure receiving surface of the piston has an inclined portion that inclines in a direction protruding from the piston as at least a part of a peripheral portion close to the inner surface of the cylinder space goes outward.   The gas control device according to claim 1, wherein the introduction flow path opens facing the pressure receiving surface.   The gas control device according to claim 1, wherein the inclined portion is formed over the entire circumference of the peripheral portion.   An elastic member that urges the piston in a direction to reduce the pressure receiving space, and an open state when the pressure in the pressure receiving space becomes less than a first predetermined pressure, and a closed state when the pressure exceeds a second predetermined pressure The gas control device according to any one of claims 1 to 3, further comprising: a valve device that is opened and closed according to an axial position of the piston and connected to an upstream side of the introduction flow path. .

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