Pressure reducing valve

Abstract

The pressure reducing valve of the present invention is used for a high-pressure tank. The pressure reducing valve includes: a discharge flow path capable of discharging deposits accumulated in the high-pressure tank from the inside of the high-pressure tank to the outside of the high-pressure tank; a valve body disposed in the discharge flow path and supported so as to be movable between a closed position for closing the discharge flow path and an open position for opening the discharge flow path; a limiting member supported so as to be movable between a first position for restraining the valve body at the closed position and a second position for allowing the valve body to move to the open position; and a plurality of temperature-sensitive operating mechanisms connected to the limiting member. Each of the plurality of temperature-sensitive operating mechanisms moves the limiting member from the first position to the second position when sensing a temperature above a reference value.

Description

Technical Field

[0001] The technology disclosed in this specification relates to a pressure reducing valve. Background Art

[0002] A pressure reducing valve is disclosed in Japanese Unexamined Patent Application Publication No. 2019-044863. The pressure reducing valve is used for a high-pressure tank. The pressure reducing valve includes: a discharge flow path capable of discharging deposits accumulated in the high-pressure tank from the inside of the high-pressure tank to the outside of the high-pressure tank; a valve body disposed in the discharge flow path and supported so as to be movable between a closed position for closing the discharge flow path and an open position for opening the discharge flow path; a limiting member supported so as to be movable between a first position for restraining the valve body at the closed position and a second position for allowing the valve body to move to the open position; and a melting member that melts at a temperature above a reference value. When the melting member melts, the limiting member moves from the first position to the second position.

[0003] For example, in the case where the high-pressure tank is exposed to high temperature due to a fire or the like, the above-mentioned melting member melts. In the above pressure reducing valve, for example, when the temperature becomes high on the first direction side with respect to the pressure reducing valve, the melting member can be melted. On the other hand, when the temperature becomes high on the second direction side different from the first direction with respect to the pressure reducing valve, it takes time for the melting member to melt. In order to quickly melt the melting member even when the temperature becomes high on the second direction side with respect to the pressure reducing valve, the pressure reducing valve needs to further include a set of a limiting member and a melting member. In this structure, the structure of the pressure reducing valve becomes complicated. In this specification, a technology is disclosed that can suppress the structure of the pressure reducing valve from becoming complicated and can quickly discharge the deposits in the high-pressure tank even when the high-pressure tank is exposed to high temperature from various directions. Summary of the Invention

[0004] The pressure reducing valve disclosed in this specification is used for a high-pressure tank. The pressure reducing valve includes: a discharge flow path capable of discharging deposits accumulated in the high-pressure tank from the inside of the high-pressure tank to the outside of the high-pressure tank; a valve body disposed in the discharge flow path and supported so as to be movable between a closed position for closing the discharge flow path and an open position for opening the discharge flow path; a limiting member supported so as to be movable between a first position for restraining the valve body at the closed position and a second position for allowing the valve body to move to the open position; and a plurality of temperature-sensitive working mechanisms connected to the limiting member. Each of the plurality of temperature-sensitive working mechanisms moves the limiting member from the first position to the second position when sensing a temperature above a reference value.

[0005] In the above structure, a plurality of temperature-sensitive operating mechanisms are connected to a limiting member. Therefore, when the high-pressure tank is exposed to high temperature, any one of the plurality of temperature-sensitive operating mechanisms moves the limiting member from the first position to the second position, whereby the valve body can be quickly moved from the closed position to the open position. Thus, even when the high-pressure tank is exposed to high temperature from various directions, the deposits in the high-pressure tank can be quickly discharged through the discharge flow path. Since a single limiting member is shared by the plurality of temperature-sensitive operating mechanisms, the structure of the pressure reducing valve can also be prevented from becoming complicated.

[0006] The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals denote like elements. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 is a side view of a pressure reducing valve for a vehicle and a hydrogen high-pressure tank.

[0008] Figure 2 is a cross-sectional view near the discharge mechanism when the limiting member is in the first position and the valve body 24 is in the closed position.

[0009] Figure 3 is a cross-sectional view near the discharge mechanism when the limiting member is in the second position and the valve body 24 is in the open position.

[0010] Figure 4 is a cross-sectional view of the first temperature-sensitive operating mechanism 40 and the second temperature-sensitive operating mechanism 42 when the limiting member is in the first position.

[0011] Figure 5 is a cross-sectional view of the first temperature-sensitive operating mechanism 40 and the second temperature-sensitive operating mechanism 42 when the limiting member is in the second position. DETAILED DESCRIPTION

[0012] It may also be configured such that, on the basis of an embodiment of the present technology, each of the plurality of temperature-sensitive operating mechanisms includes a melting member that melts at a temperature equal to or higher than a reference value.

[0013] In a structure in which each of the plurality of temperature-sensitive operating mechanisms does not include a melting member but includes a sensor, in the case where the sensor malfunctions, even if the high-pressure tank is exposed to high temperature, the limiting member cannot be moved from the first position to the second position. According to the above structure, when the high-pressure tank is exposed to high temperature, the melting member melts. Thus, the limiting member can be reliably moved from the first position to the second position.

[0014] It can also be configured as follows: based on an embodiment of the present technology, each of the multiple temperature-sensitive working mechanisms further includes a shaft member that can move between an initial position and a working position and is biased toward the working position. It can also be configured as follows: when the shaft member moves from the initial position to the working position, the limiting member is moved from the first position to the second position. It can also be configured as follows: the melting member holds the shaft member at the initial position.

[0015] In the above structure, the melting member does not melt at a temperature lower than the reference value. Therefore, when the melting member does not melt, the shaft member is reliably held at the initial position. Therefore, when the temperature is lower than the reference value, the shaft member does not move toward the working position. It is possible to prevent the limiting member from moving from the first position to the second position.

[0016] It can also be configured as follows: based on an embodiment of the present technology, each of the multiple temperature-sensitive working mechanisms further includes a biasing member that biases the shaft member toward the working position.

[0017] In the above structure, with a simple structure, when the melting member melts, the shaft member can be quickly moved toward the working position.

[0018] It can also be configured as follows: based on an embodiment of the present technology, the limiting member and the valve body are formed of mutually independent members.

[0019] In the case where the limiting member and the valve body are an integral member, the integral member needs to have both a structure for closing the discharge flow path and a structure for switching from the state of closing the discharge flow path to the state of opening the discharge flow path. As a result, the structure of the integral member becomes complicated. In the above structure, it is possible to prevent the structures of the limiting member and the valve body from becoming complicated.

[0020] It can also be configured as follows: based on an embodiment of the present technology, the direction in which the limiting member moves between the first position and the second position is different from the direction in which the valve body moves between the closed position and the open position.

[0021] In the above structure, it is possible to prevent the pressure reducing valve from becoming large in the direction in which the valve body moves between the closed position and the open position.

[0022] It can also be configured as follows: based on an embodiment of the present technology, the limiting member is supported so as to be able to rotate about a rotation axis between the first position and the second position.

[0023] In the above structure, with a simple structure, the limiting member can be moved from the first position to the second position.

[0024] It can also be configured as follows: based on an embodiment of the present technology, multiple temperature-sensing working mechanisms include a first temperature-sensing working mechanism and a second temperature-sensing working mechanism. It can also be configured such that the connection position between the first temperature-sensing working mechanism and the limiting member is arranged to have an interval of more than 120 degrees around the rotation axis relative to the connection position between the second temperature-sensing working mechanism and the limiting member.

[0025] In a structure where the connection position between the first temperature-sensing working mechanism and the limiting member is arranged to have an interval of less than 120 degrees around the rotation axis relative to the connection position between the second temperature-sensing working mechanism and the limiting member, for example, when it becomes high temperature on the side opposite to the first temperature-sensing working mechanism with respect to the limiting member, there may be a situation where it takes time for both the first temperature-sensing working mechanism and the second temperature-sensing working mechanism to operate. In the above structure, even when the high-pressure tank is exposed to high temperature from various directions, at least one of the first temperature-sensing working mechanism and the second temperature-sensing working mechanism can operate quickly.

[0026] It can also be configured as follows: based on an embodiment of the present technology, the high-pressure tank is mounted on a vehicle and arranged between a lower protection member of the vehicle located below the high-pressure tank and an upper protection member of the vehicle located above the high-pressure tank. It can also be configured such that the first temperature-sensing working mechanism is arranged at a position closer to the upper protection member side than the limiting member. The second temperature-sensing working mechanism is arranged at a position closer to the lower protection member side than the limiting member.

[0027] In the above structure, in both situations where it becomes high temperature on the upper protection member side with respect to the high-pressure tank and where it becomes high temperature on the lower protection member side with respect to the high-pressure tank, the temperature-sensing working mechanism can operate quickly.

[0028] It can also be configured as follows: based on an embodiment of the present technology, the deposit is hydrogen.

[0029] Hydrogen stored in a high-pressure tank under a high-temperature environment is very dangerous. Therefore, when the high-pressure tank is exposed to high temperature, it is necessary to reliably discharge hydrogen from the high-pressure tank. In the above structure, even when using a high-pressure tank storing hydrogen, the structure of the pressure reducing valve can be prevented from becoming complicated, and even when the high-pressure tank is exposed to high temperature from various directions, the hydrogen in the high-pressure tank can be reliably discharged through the discharge flow path.

[0030] (Example)

[0031] In this embodiment, with reference to Figures 1 to 5 , the pressure reducing valve 10 will be described. As Figure 1As shown, the pressure reducing valve 10 is used for the high-pressure tank 2. Hydrogen is stored in the high-pressure tank 2. The high-pressure tank 2 is used, for example, as a supply source for supplying hydrogen to a fuel cell. The high-pressure tank 2 is mounted on a vehicle 100 such as an electric vehicle. First, with reference to Figure 1 , the vehicle 100 equipped with the high-pressure tank 2 will be described.

[0032] The vehicle 100 includes a lower side protection member 102 and an upper side protection member 104. The lower side protection member 102 and the upper side protection member 104 are located at the lower part of the vehicle 100. The lower side protection member 102 is disposed at a position closer to the traveling surface (not shown) on which the vehicle 100 travels than the upper side protection member 104. Hereinafter, the direction close to the traveling surface will be referred to as the downward direction, and the direction away from the traveling surface will be referred to as the upward direction. The upper side protection member 104 is disposed at a position above the lower side protection member 102 and is separated from the lower side protection member 102. Thus, a tank chamber 106 is formed between the lower side protection member 102 and the upper side protection member 104. The high-pressure tank 2 is disposed in the tank chamber 106.

[0033] The lower side protection member 102 includes a lower side plate member 110, an intermediate plate member 112, an upper side plate member 114, and a heat insulating member 116. The lower side plate member 110 is made of a metal material, such as aluminum. The lower side plate member 110 has a lower side opening 110a that penetrates the lower side plate member 110. The intermediate plate member 112 is partially disposed above the lower side plate member 110. The intermediate plate member 112 is made of a metal material, such as stainless steel. The upper side plate member 114 is disposed above the intermediate plate member 112. An air layer is partially formed between the upper side plate member 114 and the lower side plate member 110. The upper side plate member 114 has an upper side opening 114a that penetrates the upper side plate member 114. In the vertical direction, the upper side opening 114a coincides with the lower side opening 110a. The heat insulating member 116 is partially disposed above the upper side plate member 114. The heat insulating member 116 suppresses the transfer of heat through the lower side protection member 102.

[0034] Next, the pressure reducing valve 10 will be described. The pressure reducing valve 10 forms a part of the valve unit 4 of the high-pressure tank 2. The pressure reducing valve 10 is configured to discharge hydrogen in the high-pressure tank 2 to the outside of the high-pressure tank 2. The pressure reducing valve 10 includes a base 12 and a discharge mechanism 14. The base 12 is a structure that constitutes the valve unit 4, and the discharge mechanism 14 is a movable mechanism provided relative to the base 12.

[0035] As shown in Figure 2 and Figure 3As shown, the base 12 is provided with a discharge flow path 16 and a storage chamber 18. When discharging hydrogen in the high-pressure tank 2 to the outside of the high-pressure tank 2, the hydrogen passes through the discharge flow path 16. The discharge flow path 16 includes a first discharge flow path 20 and a second discharge flow path 22. The second discharge flow path 22 is connected to one end of the first discharge flow path 20. One end of the first discharge flow path 20 is equivalent to the downstream end of the first discharge flow path 20 in the direction in which hydrogen in the high-pressure tank 2 flows in the first discharge flow path 20. The storage chamber 18 is connected to the downstream end of the first discharge flow path 20.

[0036] The discharge mechanism 14 includes a valve body 24, a limiting member 26, and a plurality (two in this embodiment) of temperature-sensitive working mechanisms 28. The valve body 24 is disposed in the first discharge flow path 20. The valve body 24 is supported by the base 12 so as to be linearly movable between a closed position (refer to Figure 2 ) and an open position (refer to Figure 3 ). The valve body 24 is moved from the closed position toward the open position by the pressure of hydrogen in the high-pressure tank 2. As Figure 2 shown, when the valve body 24 is in the closed position, the valve body 24 is disposed near the connection portion of the first discharge flow path 20 and the second discharge flow path 22, and blocks the second discharge flow path 22 from the first discharge flow path 20 side. Thereby, the discharge flow path 16 is closed. In this state, hydrogen in the high-pressure tank 2 is not discharged to the outside of the high-pressure tank 2. As Figure 3 shown, when the valve body 24 is in the open position, the valve body 24 is disposed across both the first discharge flow path 20 and the storage chamber 18, and does not block the second discharge flow path 22. Thereby, the discharge flow path 16 is opened. In this state, hydrogen in the high-pressure tank 2 is discharged to the outside of the high-pressure tank 2.

[0037] The limiting member 26 is separate from the valve body 24. The limiting member 26 is disposed in the storage chamber 18. The limiting member 26 is supported by the base 12 so as to be movable between a first position (refer to Figure 2 and Figure 4 ) and a second position (refer to Figure 3 and Figure 5 ). In this embodiment, the limiting member 26 is supported by the base 12 so as to be rotatable about a rotation axis RX between the first position and the second position. The rotation axis RX is parallel to the moving direction of the valve body 24. The limiting member 26 includes a limiter main body 32, a first support rod 34, and a second support rod 36.

[0038] As Figure 4 and Figure 5 shown, the limiter main body 32 has a substantially semi-circular plate shape, and the substantially semi-circular plate shape has a cutout portion 32a. In addition, in Figure 4 and Figure 5 , in order to make the shape and position of the limiting member 26 easy to understand, the limiting member 26 is marked with dotted hatching. In addition, inFigure 4 In this, the downstream end of the first discharge flow path 20 is illustrated by a dashed line. As Figure 4 shown, when the limiting member 26 is in the first position, the limiter body 32 blocks the first discharge flow path 20 from the downstream end side. At this time, as Figure 2 shown, the limiter body 32 restrains the valve body 24 in the closed position. As Figure 5 shown, when the limiting member 26 is in the second position, the cutout portion 32a of the limiter body 32 faces the downstream end of the first discharge flow path 20. The limiter body 32 does not block the first discharge flow path 20. At this time, as Figure 3 shown, the limiting member 26 allows the valve body 24 to move toward the open position.

[0039] The first support rod 34 extends outward from the limiter body 32 along the rotation axis RX. Although not shown in the figure, the second support rod 36 also extends outward from the limiter body 32 along the rotation axis RX. As Figure 4 shown, the first support rod 34 is arranged to have an interval of 120 degrees or more (180 degrees in this embodiment) around the rotation axis RX with respect to the second support rod 36.

[0040] As Figure 1 shown, the plurality of temperature-sensitive operating mechanisms 28 include a first temperature-sensitive operating mechanism 40 and a second temperature-sensitive operating mechanism 42. The first temperature-sensitive operating mechanism 40 and the second temperature-sensitive operating mechanism 42 are arranged to have an interval in the vertical direction. The first temperature-sensitive operating mechanism 40 and the second temperature-sensitive operating mechanism 42 are fixed to one end of the base 12. The first temperature-sensitive operating mechanism 40 is arranged at a position closer to the upper protective member 104 side than the limiting member 26. The second temperature-sensitive operating mechanism 42 is arranged at a position closer to the lower protective member 102 side than the limiting member 26.

[0041] As Figure 4 and Figure 5 shown, the first temperature-sensitive operating mechanism 40 includes a first housing 44, a first support member 46, a first shaft member 48, a first melting member 50, and a first biasing member 52. The first housing 44 is fixed to one end of the base 12. The first housing 44 has a substantially cylindrical shape with a bottom wall 44a at one end. A through hole 44b penetrating the bottom wall 44a in the thickness direction is formed in the bottom wall 44a of the first housing 44. The first support member 46 closes the opening at the other end of the first housing 44.

[0042] The first shaft member 48 has a substantially L-shaped configuration. The first shaft member 48 is inserted into the through hole 44b of the first housing 44. A part of the first shaft member 48 is arranged inside the first housing 44. One end of the first shaft member 48 is connected to the first support rod 34. The first shaft member 48 can be in an initial position (refer to Figure 4 ) and a working position (refer toFigure 5 ) moves up and down along the vertical direction. When the first shaft member 48 moves from the initial position toward the working position, the first shaft member 48 moves upward (i.e., toward the upper protective member 104). As Figure 5 shown, when the first shaft member 48 is in the working position, the first shaft member 48 abuts against the first support member 46.

[0043] As Figure 4 shown, the first melting member 50 is disposed inside the first housing 44. The first melting member 50 is made of a fusible metal material, for example, lead or tin. The first melting member 50 melts at a temperature above a reference value, for example, a temperature of 110 degrees or more. The first melting member 50 is disposed between the first support member 46 and the other end of the first shaft member 48. The first melting member 50 holds the first shaft member 48 in the initial position by abutting against the other end of the first shaft member 48.

[0044] The first biasing member 52 is disposed inside the first housing 44. One end of the first biasing member 52 abuts against the first housing 44, and the other end of the first biasing member 52 is connected to the first shaft member 48. The first shaft member 48 is inserted into the first biasing member 52. The first biasing member 52 is, for example, a spring member. The first biasing member 52 biases the first shaft member 48 toward the working position. Therefore, when the first melting member 50 melts, the first shaft member 48 moves toward the working position under the action of the first biasing member 52.

[0045] The second temperature-sensitive operating mechanism 42 includes a second housing 56, a second support member 58, a second shaft member 60, a second melting member 62, and a second biasing member 64. Each of the second housing 56, the second support member 58, the second shaft member 60, the second melting member 62, and the second biasing member 64 has the same structure as each of the first housing 44, the first support member 46, the first shaft member 48, the first melting member 50, and the first biasing member 52.

[0046] The positional relationship between the first temperature-sensitive operating mechanism 40 and the second temperature-sensitive operating mechanism 42 will be described. One end of the first shaft member 48 is connected to the first support rod 34, and one end of the second shaft member 60 is connected to the second support rod 36. Therefore, the connection position between the first shaft member 48 and the first support rod 34 is arranged to have an interval of 120 degrees or more (180 degrees in this embodiment) around the rotation axis RX with respect to the connection position between the second shaft member 60 and the second support rod 36. That is, the first temperature-sensitive operating mechanism 40 is arranged to have an interval of 120 degrees or more (180 degrees in this embodiment) around the rotation axis RX with respect to the second temperature-sensitive operating mechanism 42.

[0047] Next, the flow of discharging hydrogen in the high-pressure tank 2 to the outside of the high-pressure tank 2 when the high-pressure tank 2 is exposed to high temperature will be described. First, the flow of discharging hydrogen in the high-pressure tank 2 to the outside of the high-pressure tank 2 when the high-pressure tank 2 is exposed to high temperature due to the upper protective member 104 becoming high temperature will be described. In this case, at least the first temperature-sensitive operating mechanism 40 is exposed to high temperature. When the first temperature-sensitive operating mechanism 40 is exposed to high temperature, the first melting member 50 rapidly reaches a temperature above the reference value and melts.

[0048] As Figure 5 shown, when the first melting member 50 melts, the first shaft member 48 is subjected to the acting force of the first biasing member 52 and moves upward from the initial position to the working position. Along with the movement of the first shaft member 48, the limiting member 26 rotates from the first position to the second position around the rotation axis RX. At this time, the connection between the second shaft member 60 and the second support rod 36 is released by the movement of the first shaft member 48. When the limiting member 26 rotates to the second position, the notch portion 32a of the limiter main body 32 faces the downstream end of the first discharge flow path 20. As Figure 3 shown, the valve body 24 no longer abuts against the limiting member 26. Therefore, the valve body 24 is subjected to the pressure of the hydrogen in the high-pressure tank 2 and moves from the closed position to the open position along the first discharge flow path 20 (along the rotation axis RX). Thereby, the first discharge flow path 20 communicates with the second discharge flow path 22. The hydrogen in the high-pressure tank 2 is discharged to the outside of the high-pressure tank 2 through the discharge flow path 16.

[0049] Next, the flow of discharging hydrogen in the high-pressure tank 2 to the outside of the high-pressure tank 2 when the high-pressure tank 2 is exposed to high temperature due to the lower protective member 102 becoming high temperature will be described. In this case, at least Figure 4 the second temperature-sensitive operating mechanism 42 shown is exposed to high temperature. When the second temperature-sensitive operating mechanism 42 is exposed to high temperature, the second melting member 62 rapidly reaches a temperature above the reference value and melts.

[0050] When the second melting member 62 melts, the second shaft member 60 is subjected to the acting force of the second biasing member 64 and moves downward from the initial position to the working position. Along with the movement of the second shaft member 60, the limiting member 26 rotates from the first position to the second position around the rotation axis RX. At this time, the connection between the first shaft member 48 and the first support rod 34 is released by the movement of the second shaft member 60. In addition, the rotation direction of the limiting member 26 when the second temperature-sensitive operating mechanism 42 is exposed to high temperature is the same as the rotation direction of the limiting member 26 when the first temperature-sensitive operating mechanism 40 is exposed to high temperature. As Figure 3As shown, when the limiting member 26 rotates to the second position, the valve body 24 no longer abuts against the limiting member 26. Therefore, the valve body 24 moves from the closed position to the open position. The hydrogen in the high-pressure tank 2 is discharged to the outside of the high-pressure tank 2 through the discharge flow path 16.

[0051] (Effect)

[0052] In this embodiment, the pressure reducing valve 10 is used for the high-pressure tank 2. The pressure reducing valve 10 includes: a discharge flow path 16 capable of discharging hydrogen (an example of a deposit) accumulated in the high-pressure tank 2 from the inside of the high-pressure tank 2 to the outside of the high-pressure tank 2; a valve body 24 disposed in the discharge flow path 16 and supported so as to be movable between a closed position closing the discharge flow path 16 and an open position opening the discharge flow path 16; a limiting member 26 supported so as to be movable between a first position restricting the valve body 24 to the closed position and a second position allowing the valve body 24 to move to the open position; and a plurality of temperature-sensitive operating mechanisms 28 connected to the limiting member 26. Each of the plurality of temperature-sensitive operating mechanisms 28 moves the limiting member 26 from the first position to the second position when sensing a temperature above a reference value.

[0053] In the above structure, a plurality of temperature-sensitive operating mechanisms 28 are connected to one limiting member 26. Therefore, when the high-pressure tank 2 is exposed to high temperature, any one of the plurality of temperature-sensitive operating mechanisms 28 moves the limiting member 26 from the first position to the second position, whereby the valve body 24 can be quickly moved from the closed position to the open position. Thus, even when the high-pressure tank 2 is exposed to high temperature from various directions, the hydrogen in the high-pressure tank 2 can be quickly discharged through the discharge flow path 16. Since one limiting member 26 is shared by the plurality of temperature-sensitive operating mechanisms 28, the structure of the pressure reducing valve 10 can also be prevented from becoming complicated.

[0054] In addition, each of the plurality of temperature-sensitive operating mechanisms 28 includes melting members 50, 62 that melt at a temperature above a reference value.

[0055] In the above structure, in a structure in which the plurality of temperature-sensitive operating mechanisms 28 do not include the melting members 50, 62 but include sensors, when the sensor fails, even if the high-pressure tank 2 is exposed to high temperature, the limiting member 26 cannot be moved from the first position to the second position. According to the above structure, when the high-pressure tank 2 is exposed to high temperature, the melting members 50, 62 melt. Thus, the limiting member 26 can be reliably moved from the first position to the second position.

[0056] In addition, each of the plurality of temperature-sensitive working mechanisms 28 further includes shaft members 48, 60 that can move between an initial position and a working position and are biased toward the working position. When the shaft members 48, 60 move from the initial position to the working position respectively, the limiting member 26 is moved from the first position to the second position. Each of the melting members 50, 62 holds the shaft members 48, 60 at the initial position respectively.

[0057] In the above structure, the melting members 50, 62 do not melt at a temperature below the reference value. Therefore, when the melting members 50, 62 are not melted, the shaft members 48, 60 are reliably held at the initial position. Therefore, when the temperature is below the reference value, the shaft members 48, 60 do not move toward the working position. It is possible to suppress the limiting member 26 from moving from the first position to the second position.

[0058] In addition, each of the plurality of temperature-sensitive working mechanisms 28 further includes biasing members 52, 64 that bias the shaft members 48, 60 toward the working position.

[0059] In the above structure, with a simple structure, when the melting members 50, 62 melt, the shaft members 48, 60 can be quickly moved toward the working position.

[0060] In addition, the limiting member 26 and the valve body 24 are composed of mutually independent components.

[0061] In the case where the limiting member 26 and the valve body 24 are an integral part, the integral part needs to have both a structure for closing the discharge flow path 16 and a structure for switching from the state of closing the discharge flow path 16 to the state of opening the discharge flow path 16. As a result, the structure of the integral part becomes complicated. In the above structure, it is possible to suppress the structures of the limiting member 26 and the valve body 24 from becoming complicated.

[0062] In addition, the direction in which the limiting member 26 moves between the first position and the second position is different from the direction in which the valve body 24 moves between the closed position and the open position.

[0063] In the above structure, it is possible to suppress the pressure reducing valve 10 from becoming large in the direction in which the valve body 24 moves between the closed position and the open position.

[0064] In addition, the limiting member 26 is supported so as to be able to rotate about the rotation axis RX between the first position and the second position.

[0065] In the above structure, with a simple structure, the limiting member 26 can be moved from the first position to the second position.

[0066] In addition, a plurality of temperature-sensitive working mechanisms 28 include a first temperature-sensitive working mechanism 40 and a second temperature-sensitive working mechanism 42. The connection position between the first temperature-sensitive working mechanism 40 and the limiting member 26 is arranged to have an interval of 120 degrees or more (180 degrees in this embodiment) around the rotation axis RX with respect to the connection position between the second temperature-sensitive working mechanism 42 and the limiting member 26.

[0067] In a structure where the connection position between the first temperature-sensitive working mechanism 40 and the limiting member 26 is arranged to have an interval of less than 120 degrees around the rotation axis RX with respect to the connection position between the second temperature-sensitive working mechanism 42 and the limiting member 26, for example, when it becomes high temperature on the side opposite to the first temperature-sensitive working mechanism 40 with respect to the limiting member 26, there may be a situation where it takes time for both the first temperature-sensitive working mechanism 40 and the second temperature-sensitive working mechanism 42 to operate. In the above structure, even when the high-pressure tank 2 is exposed to high temperature from various directions, at least one of the first temperature-sensitive working mechanism 40 and the second temperature-sensitive working mechanism 42 can operate quickly.

[0068] In addition, the high-pressure tank 2 is mounted on the vehicle 100 and is disposed between the lower protection member 102 of the vehicle 100 located below the high-pressure tank 2 and the upper protection member 104 of the vehicle 100 located above the high-pressure tank 2. The first temperature-sensitive working mechanism 40 is disposed at a position closer to the upper protection member 104 than the limiter 26 member. The second temperature-sensitive working mechanism 42 is disposed at a position closer to the lower protection member 102 than the limiting member 26.

[0069] In the above structure, in both situations where it becomes high temperature on the upper protection member 104 side with respect to the high-pressure tank 2 and where it becomes high temperature on the lower protection member 102 side with respect to the high-pressure tank 2, the temperature-sensitive working mechanism 28 can operate quickly.

[0070] In addition, hydrogen is stored in the high-pressure tank 2.

[0071] Hydrogen stored in the high-pressure tank 2 is dangerous when disposed in a high-temperature environment. Therefore, when the high-pressure tank 2 is exposed to high temperature, it is necessary to reliably discharge hydrogen from the high-pressure tank 2. In the above structure, even when using the high-pressure tank 2 storing hydrogen, the structure of the pressure reducing valve 10 can be prevented from becoming complicated, and even when the high-pressure tank 2 is exposed to high temperature from various directions, the hydrogen in the high-pressure tank 2 can be reliably discharged through the discharge flow path 16.

[0072] The specific examples of the present invention have been described in detail above, but these are merely illustrative and do not limit the claims. The technology described in the claims includes technologies obtained by various deformations and changes to the above-described specific examples.

[0073] In a modified example, the first temperature-sensitive working mechanism 40 may also be provided with a first temperature sensor instead of the first melting member 50, and the second temperature-sensitive working mechanism 42 may also be provided with a second temperature sensor instead of the second melting member 62. If the first temperature sensor senses a temperature equal to or higher than a reference value, the first shaft member 48 may also move from the initial position toward the working position. If the second temperature sensor senses a temperature equal to or higher than a reference value, the second shaft member 60 may also move from the initial position toward the working position.

[0074] In a modified example, the limiting member 26 may also be supported so as to be linearly movable between a first position and a second position.

[0075] In a modified example, the direction in which the limiting member 26 rotates when the second temperature-sensitive working mechanism 42 is exposed to high temperature may also be opposite to the direction in which the limiting member 26 rotates when the first temperature-sensitive working mechanism 40 is exposed to high temperature.

[0076] In a modified example, the number of temperature-sensitive working mechanisms provided in the plurality of temperature-sensitive working mechanisms 28 is not limited to two, and may also be three or more. When the number of temperature-sensitive working mechanisms provided in the plurality of temperature-sensitive working mechanisms 28 is three, the plurality of temperature-sensitive working mechanisms 28 may also be further provided with a third temperature-sensitive working mechanism. In this case, the first temperature-sensitive working mechanism 40, the second temperature-sensitive working mechanism 42, and the third temperature-sensitive working mechanism may also be arranged to have equal intervals around the rotation axis RX, that is, intervals of 120 degrees.

[0077] In a modified example, the high-pressure tank 2 may also store deposits other than hydrogen, for example, store oxygen.

[0078] The technical elements described in this specification or the drawings exhibit technical utility either individually or in various combinations, and are not limited to the combinations recited in the claims at the time of application. In addition, the technologies exemplified in this specification or the drawings can achieve multiple purposes simultaneously, and achieving one of the purposes itself has technical utility.

Claims

1. A pressure reducing valve for a high-pressure tank, wherein the pressure reducing valve comprises: a discharge flow path capable of discharging deposits accumulated in the high-pressure tank from the inside of the high-pressure tank to the outside of the high-pressure tank; a valve body disposed in the discharge flow path and supported so as to be movable between a closed position for closing the discharge flow path and an open position for opening the discharge flow path; a limiting member supported so as to be movable between a first position for restraining the valve body at the closed position and a second position for allowing the valve body to move to the open position; and a plurality of temperature-sensitive working mechanisms connected to the limiting member, the plurality of temperature-sensitive working mechanisms respectively move the limiting member from the first position to the second position when sensing a temperature above a reference value, the limiting member is supported so as to be rotatable about a rotation axis between the first position and the second position, the plurality of temperature-sensitive working mechanisms include a first temperature-sensitive working mechanism and a second temperature-sensitive working mechanism, a connection position between the first temperature-sensitive working mechanism and the limiting member is arranged to have an interval of 120 degrees or more around the rotation axis with respect to a connection position between the second temperature-sensitive working mechanism and the limiting member.

2. The pressure reducing valve according to claim 1, wherein the plurality of temperature-sensitive working mechanisms respectively include a melting member that melts at a temperature above the reference value.

3. The pressure reducing valve according to claim 2, wherein the plurality of temperature-sensitive working mechanisms respectively further include a shaft member that can move between an initial position and a working position and is biased toward the working position, the shaft member moves the limiting member from the first position to the second position when moving from the initial position to the working position, the melting member holds the shaft member at the initial position.

4. The pressure reducing valve according to claim 3, wherein the plurality of temperature-sensitive working mechanisms respectively further include a biasing member that biases the shaft member toward the working position.

5. The pressure reducing valve according to claim 1, wherein the limiting member and the valve body are composed of mutually independent components.

6. The pressure reducing valve according to claim 5, wherein a moving direction of the limiting member between the first position and the second position is different from a moving direction of the valve body between the closed position and the open position.

7. The pressure reducing valve according to claim 1, wherein the high-pressure tank is mounted on a vehicle and is disposed between a lower protection member of the vehicle located below the high-pressure tank and an upper protection member of the vehicle located above the high-pressure tank, the first temperature-sensitive working mechanism is disposed at a position closer to the upper protection member side than the limiting member, the second temperature-sensitive working mechanism is disposed at a position closer to the lower protection member side than the limiting member.

8. The pressure reducing valve according to any one of claims 1 to 7, wherein the deposit is hydrogen.

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