Patent ID: 12221943

DETAILED DESCRIPTION

In the drawings, structurally identical or functionally similar features are indicated by identical reference labels. In addition, in the drawings, hatching lines of the same component might be presented in different ways in different views, but it should not be imagined that this will have any effect on the understanding of the technical solution of the disclosure. For example, inFIGS.2and3, the hatching lines of the same component will have different densities and lie in different directions for reasons relating to the way in which the drawings are produced, but this will not affect the understanding of the technical solution of the disclosure.

FIG.1shows schematically a part of a fluid supply system1that can be used in a fuel cell vehicle. For example, the fluid supply system1may provide a gas such as high-pressure hydrogen or high-pressure air for a battery of a fuel cell of the vehicle, but may also provide a liquid such as water for normal operation of the fuel cell. In the disclosure, the gas and liquid are collectively called fluid. The fluid supply system1comprises a high-pressure fluid tank20, with high-pressure fluid being stored therein.

The fluid supply system1is described below, taking hydrogen alone as an example. However, those skilled in the art will understand that any other suitable high-pressure fluid for ensuring normal operation of the fuel cell may also be applied to the technical content associated with the description of hydrogen and involving the following.

The high-pressure fluid tank20may be a hydrogen tank. The high-pressure fluid tank20is connected in a sealed fashion to a high-pressure pipeline10aof the fluid supply system1, wherein the high-pressure pipeline10ais fluid-connected via a pressure regulating valve40to a low-pressure pipeline10bof the fluid supply system1. The fluid supply system1further comprises a supply nozzle30disposed in the low-pressure pipeline10b. Thus, high-pressure hydrogen is first of all stored in the high-pressure fluid tank20; high-pressure hydrogen is outputted from the high-pressure fluid tank20via the high-pressure pipeline10aas needed, and enters the low-pressure pipeline10bafter being reduced in pressure by the pressure regulating valve40, and is further supplied to the battery of the fuel cell via the supply nozzle30, in order to realize an electrochemical reaction and generate electric power.

When the fluid supply system1is damaged due to the vehicle having an accident, e.g. being involved in a collision, the high-pressure fluid tank20might be subjected to an abnormal high temperature, causing an abnormal increase in fluid pressure therein and in turn causing an explosion. In order to avoid the possibility of the high-pressure fluid tank20exploding due to this kind of accident, a pressure relief valve according to the disclosure may be disposed in the high-pressure fluid tank20and/or the high-pressure pipeline10a. For example, as indicated by the arrows100, such a pressure relief valve may be disposed at an outlet of the high-pressure fluid tank20, e.g. connected in parallel with an output valve (not shown) at the outlet; and/or such a pressure relief valve may be disposed in a wall of the high-pressure fluid tank20.

An example of the pressure relief valve100is now described with reference toFIGS.2and3. As shown in the figures, the pressure relief valve100comprises a substantially tubular valve body component101. A hollow internal cavity200is defined by an inner wall of the valve body component101. The internal cavity200has two openings opposite each other, one of these openings being at the left side in the figures and the other being at the right side in the figures; the two openings are in communication with a high-pressure side and a low-pressure side of the pressure relief valve100respectively. InFIGS.1and2, the left side is regarded as the high-pressure side of the pressure relief valve100, and is for example in communication with the outlet of the high-pressure fluid tank20or in communication with the high-pressure pipeline10a; the right side is regarded as the low-pressure side of the pressure relief valve100, and is for example in communication with the external atmosphere or in communication with another low-pressure fluid pipeline.

From the high-pressure side of the valve body component101, a base component102is installed in the valve body component101and partially exposed. For example, a thread is formed on an outer peripheral surface of the base component102, and a thread is also formed on a corresponding inner peripheral surface of the valve body component101, in order that the two components can be screwed together. A hollow internal cavity203is also formed in the base component102. Once the base component102has been installed in the valve body component101, the internal cavity203can be in communication with the internal cavity200. In this case, an opening of the internal cavity203in communication with the internal cavity200(e.g. the left-side opening inFIG.2) is in communication with the high-pressure side of the pressure relief valve100.

An outer wall of the base component102is formed to have a large-diameter portion102aand a small-diameter portion102b, wherein the outer diameter of the large-diameter portion102amay be substantially the same as the outer diameter of the valve body component101, and an external thread is formed on the small-diameter portion102b, in order to engage with an internal thread formed on an inner wall of the valve body component101. The base component102and valve body component101form a valve body of the pressure relief valve101after being fitted together.

In the internal cavity203of the base component102, an inner wall of the base component102forms a step face102c, which is an annular face perpendicular to a longitudinal axis of the valve body. The step face102cis substantially located in a region where the large-diameter portion102aof the base component102is positioned in the direction of the longitudinal axis. An annular groove102dis also formed around the step face102c, and is configured to have a sealing ring108installed therein. An inner sleeve106is installed in the base component102. An external thread is formed on an outer wall of the inner sleeve106, in order to engage with an internal thread formed on an inner wall of the base component102. The inner sleeve106is also substantially tubular, and has two flat end faces opposite each other. The inner sleeve106has a hollow internal cavity204defined by an inner wall thereof.

In addition, a separating plate107is clamped and fixed between the base component102and the inner sleeve106. The separating plate107is configured to isolate the high-pressure side and low-pressure side of the pressure relief valve100from one another in a sealed fashion, under the action of a securing force between the base component102and the inner sleeve106. For example, when assembly is performed, the sealing ring108may first of all be placed into the annular groove102dof the base component102; the thickness of the sealing ring108may be configured to be slightly greater than the axial depth of the annular groove102d, such that when the separating plate107is installed in the direction of the step face102cof the base component102, it will first come into contact with the sealing ring108. The inner sleeve106is then screwed via the threads into the base component102from the side where an end face102eof the base component102is positioned, finally causing one flat end face of the inner sleeve106to press against the separating plate107and in turn squeeze the sealing ring108. When the inner sleeve106is finally screwed into place in the base component102, the flat end face106aof the inner sleeve106that is opposite the flat end face in contact with the separating plate107can be flush with the end face102eof the base component102. The cooperation of the sealing ring108and the separating plate107ensures gas-tight separation of the internal cavities at the two opposite sides of the separating plate107, i.e. part of the internal cavity203located at that side of the separating plate107which is close to the high-pressure side of the pressure relief valve100(the left side inFIGS.1and2) and the internal cavity204of the inner sleeve106located at that side of the separating plate107which is close to the low-pressure side of the pressure relief valve100(the right side inFIGS.1and2).

The internal cavity200of the valve body component101comprises a large-diameter internal cavity portion200aand a small-diameter internal cavity portion200bwhich are defined by inner walls of the valve body component101, wherein the large-diameter internal cavity portion200aand small-diameter internal cavity portion200bare in communication with the internal cavity204of the inner sleeve106once the valve body component101has been fitted into place. The large-diameter internal cavity portion200ais connected to the small-diameter internal cavity portion200bat a step face101aformed by an inner wall of the valve body component101. In addition, a spring seat103is slideably located in the internal cavity200of the valve body component101. The spring seat103is also a hollow structure, and an inner wall thereof defines a hollow internal cavity201of the spring seat103. Viewed from the outside, the spring seat103also comprises a large-diameter portion103aand a small-diameter portion103b, wherein the large-diameter portion103afurther comprises an annular flange103c.

The large-diameter portion103aof the spring seat103may be slideably supported in the large-diameter internal cavity portion200aof the valve body component101by an inner wall of the valve body component101using the annular flange103c; the small-diameter portion103bof the spring seat103may be slideably supported in the small-diameter internal cavity portion200bof the valve body component101by an inner wall of the valve body component101. The outer diameter of the large-diameter portion103aof the spring seat103is smaller than the diameter of the large-diameter internal cavity portion200aof the valve body component101, such that a coil spring104can be arranged between an outer diameter part of the spring seat103, in particular of the large-diameter portion103athereof, and an inner wall of the valve body component101. One end of the coil spring104may abut the step face101aof the valve body component101, and another, opposite end may abut the annular flange103cof the spring seat103.

Furthermore, a piercing component105is fixed on an end face, opposite the coil spring104, of the annular flange103c. The piercing component105comprises a base105a, and a sharp part105bthat is integrally formed with the base105aand extends axially from the base105a. The piercing component105is also a hollow structure, and defines a hollow internal cavity202that runs axially through the base105aand the sharp part105b. A through-hole may be formed in the base105a, in order to fix the base105ato the annular flange103cvia a bolt, as shown inFIGS.2and3. The sharp part105bhas a pointed end formed by an oblique face, for piercing the separating plate107.

FIG.2shows a schematic sectional view of the pressure relief valve100in a cut-off state; in the cut-off state, the separating plate107remains intact and undamaged, such that the high-pressure side and low-pressure side of the pressure relief valve100are isolated from one another.FIG.3shows a schematic sectional view of the pressure relief valve100in a pressure relief state; in the pressure relief state, the separating plate107is pierced by the sharp part105b, such that the high-pressure side and low-pressure side of the pressure relief valve100are in communication with each other.

In a region where the small-diameter internal cavity portion200bof the internal cavity200of the valve body component101is positioned, a radial through-hole is formed in a wall of the valve body component101, in which through-hole a plug member109can be inserted. A blind hole119is formed in the plug member109; a locking pin120can be inserted in the blind hole119for example in a shape-fitted manner or friction-fitted manner, so as to be partially exposed through the blind hole119. In the cut-off state as shown inFIG.2, the plug member109is inserted in the through-hole in a sidewall of the valve body component101, and the exposed part of the locking pin120is inserted into a radial through-hole113in the small-diameter portion103bof the spring seat103, thereby locking the spring seat103, and thus the piercing component105, in place in the axial direction.

The outer diameter of the sharp part105bof the piercing component105is smaller than the diameter of the hollow internal cavity204of the inner sleeve106, thus the sharp part105bcan extend into the internal cavity204. However, in the cut-off state as shown inFIG.2, the pointed end of the sharp part105bis spaced apart from the separating plate107by a certain distance, while the base105ais also spaced apart from the flat end face106aof the inner sleeve106and/or the end face102eof the base component102by a certain distance.

For example, when the pressure relief valve100is assembled, the coil spring104can first be placed in the large-diameter internal cavity portion200aof the valve body component101such that one end thereof is in contact with the step face101a; the spring seat103with the piercing component105already fixed thereto is then inserted into the large-diameter internal cavity portion200a, such that the annular flange103cof the spring seat103comes into contact with the other, opposite end of the coil spring104. Next, a special tool is used to press the spring seat103, such that the small-diameter portion103bthereof slides axially in the small-diameter internal cavity portion200bof the valve body component101, and finally a step face between the large-diameter portion103aand small-diameter portion103bof the spring seat103comes into contact with the step face101aof the valve body component101, at which time the radial through-hole113of the spring seat103and the through-hole in the valve body component101for insertion of the plug member109are coaxial. Thus, the plug member109can be inserted into the through-hole of the valve body component101, in order to lock the spring seat103and piercing component105axially in place in the valve body component101. Next, the base component102with the separating plate107and inner sleeve106already fitted thereto is screwed into the valve body component101from the high-pressure side, such that the sharp part105bof the piercing component105enters the hollow internal cavity204of the inner sleeve106, and the pointed end of the sharp part105bis spaced apart from the separating plate107by a certain distance, while the base105ais also spaced apart from the flat end face106aof the inner sleeve106and/or the end face102eof the base component102by a certain distance.

The axial length of the piercing component105may be set such that when the pressure relief valve100is assembled and in the cut-off state as shown inFIG.2, the pointed end of the sharp part105bis just out of contact with the separating plate107, thereby ensuring that if the piercing component105is merely moved towards the separating plate107, the pointed end of the sharp part105bmust be able to touch the separating plate107. In addition, the coil spring104is configured to always apply to the spring seat103a force tending to cause it to move from the low-pressure side of the pressure relief valve100towards the high-pressure side.

In the embodiment of the disclosure, the locking pin120may be made of a fusible material, e.g. a fusible alloy. For example, such a fusible alloy may be selected from any suitable fusible alloy currently available on the market, as long as the strength thereof can suddenly weaken in a specific temperature range, so that the locking pin120is unable to support the force of the coil spring104to maintain the cut-off state of the pressure relief valve100. Taking hydrogen as an example, the fusible alloy used to make the locking pin120may be selected so as to have a melting point in the range of 110° C.±5° C. The dimensions of the locking pin120are designed such that below this range, the locking pin120is able to support the force of the coil spring104in order to keep the pressure relief valve100in the cut-off state as shown inFIG.2.

In the process of using the pressure relief valve100, the pressure relief valve100is for example installed at the outlet of the high-pressure fluid tank20, in the cut-off state as shown inFIG.2, such that the high-pressure side of the pressure relief valve100is in communication with high-pressure fluid, and the low-pressure side of the pressure relief valve100is in communication with the atmosphere or another low-pressure pipeline. In the course of normal use, the locking pin120locks the spring seat103immovably, thus the separating plate107isolates the high-pressure side from the low-pressure side. When the ambient temperature of the pressure relief valve100reaches or exceeds some value in the range of 110° C.±5° C., the state of the locking pin120changes such that the strength thereof is not enough to support the force of the coil spring104. For example, the locking pin120breaks or is truncated, and under the action of the force of the coil spring104, the spring seat103is rapidly driven towards the high-pressure side, taking the piercing component105with it, such that the sharp part105bof the piercing component105pierces the separating plate107, and finally, due to the base105acoming into contact with the flat end face106aand/or the end face102eof the base component102, the piercing component105will be stopped, such that the pressure relief valve100is in the pressure relief state as shown inFIG.3. In the pressure relief state, the internal cavities203,204,202,201and200are all in communication with each other, i.e. the high-pressure side and low-pressure side of the pressure relief valve100are in communication with each other, such that high-pressure fluid can rapidly empty from the high-pressure fluid tank20, avoiding an accident. In the technical solution of the disclosure, the locking pin120forming a pressure relief valve locking means is configured to fail only at a specific temperature or in a temperature range, and the locking pin120is designed to be spaced apart from the sealing ring108forming a pressure relief valve sealing structure; thus, the locking means of the pressure relief valve100will not affect the reliability of the sealing structure. That is to say, slow leakage of high-pressure fluid from a container at the high-pressure side, e.g. the high-pressure fluid tank20, due to ageing of the locking means because the locking means and sealing structure have been integrated with one another will not occur. In addition, a locking means that is activated on the basis of temperature better ensures that the pressure relief valve100can open rapidly at an abnormally high temperature.

As shown inFIGS.2and3, in an embodiment of the disclosure, the separating plate107is designed such that a part of the separating plate107that is within the hollow internal cavity203of the base component102protrudes towards the high-pressure side and is shaped in such a way as to form part of a spherical surface. In the disclosure, the expression “the separating plate protrudes towards the high-pressure side and is shaped in such a way as to form part of a spherical surface” means that the centre of the sphere is close to the low-pressure side opposite the high-pressure side. Due to this design, pressure from high-pressure fluid is in the opposite direction to that of the protrusion of the separating plate107, thereby ensuring that for the same thickness of separating plate107, the separating plate107of the disclosure can withstand a greater fluid pressure than a flatter separating plate.

In addition, in an embodiment of the disclosure, the piercing component105and spring seat103are then fitted together, thereby forming a penetrating member capable of sliding linearly in the valve body, wherein the spring seat103is made of a cheaper, common, machine-manufactured steel material or more lightweight aluminium alloy with no need for special heat treatment, but the piercing component105is made of a more expensive, special-purpose, high-hardness material with special heat treatment; thus, it is possible to ensure that the pressure relief valve according to the disclosure is manufactured at a rational cost and a light weight. Those skilled in the art will know that in an alternative embodiment, the piercing component105and spring seat103may also be made integrally as the penetrating member from a more expensive, special-purpose, high-hardness material with special heat treatment.

In an embodiment of the disclosure, the penetrating member applies a force from the low-pressure side towards the high-pressure side via the coil spring104; however, in an alternative embodiment, the coil spring104may also be replaced by another elastic component having the same function. For example, in an alternative embodiment, such an elastic component may also be a hollow elastic corrugated tube structure arranged in the internal cavity of the valve body, being fitted round a part of the penetrating member, so as to apply a force, acting from the low-pressure side towards the high-pressure side, to the penetrating member relative to the valve body.

In the embodiment shown in the drawings, the locking pin120forms the locking means according to the disclosure, being configured to lock the piercing component105and/or spring seat103as part of the penetrating member in the cut-off state of the pressure relief valve100. However, those skilled in the art will know that the locking means is not limited to the example shown. For example, the quantity of the locking pin120may be one, or more than one. As another example, in an alternative embodiment, the locking means may comprise a structure of another shape made of a fusible alloy, which acts between the valve body and the spring seat103, in order to lock the spring seat103relative to the valve body.

Although specific embodiments of the disclosure have been described here in detail, these are provided solely for explanatory purposes, and should not be regarded as limiting the scope of the disclosure. In addition, those skilled in the art will know that the various embodiments described herein may be used in combination with each other. Various substitutions, changes and modifications can be conceived, on condition that the spirit and scope of the disclosure are not deviated from.