CN-121986033-A - Safety device for high pressure gas tank

Abstract

A safety device (10) for a high-pressure gas tank (3) that accommodates high-pressure gas as fuel of a vehicle (2) is provided with a safety valve (1) attached to the high-pressure gas tank (3) and a heat pipe (5) attached to the safety valve (1). The safety valve (1) discharges the high-pressure gas from the inside of the high-pressure gas tank (3) to the outside as the temperature increases. The heat pipe (5) moves heat by evaporation and condensation of the working fluid enclosed therein and capillary phenomenon of a wick provided on the inner wall.

Inventors

• S. I. amarasinghe

Assignees

• 三菱扶桑卡客车公司

Dates

Publication Date

20260505

Application Date

20240826

Priority Date

20231211

Claims (14)

1. 1. A safety device for a high-pressure gas tank which accommodates therein a high-pressure gas as a fuel for a vehicle, characterized in that, The safety device is provided with: a relief valve attached to the high-pressure gas tank and configured to release the high-pressure gas from the inside to the outside of the high-pressure gas tank as the temperature rises, and And a heat pipe connected to the safety valve, and configured to move heat by evaporation and condensation of the working fluid enclosed therein and capillary phenomenon of a wick provided on an inner wall.
2. 2. The safety device for a high-pressure gas tank according to claim 1, wherein, The high-pressure gas tank has a cylindrical middle part and a pair of hemispherical end parts formed on both sides of the middle part, The safety valve is mounted on at least one of the end portions, The heat pipe includes a main pipe extending from the relief valve mounted to the end portion along the intermediate portion.
3. 3. The safety device for a high pressure gas tank according to claim 2, wherein, The high-pressure gas tank is mounted on the vehicle in a posture in which a center of the intermediate portion extends in a horizontal direction, The main pipe extends downward from the relief valve attached to the end portion and then extends along the intermediate portion.
4. 4. The safety device for a high pressure gas tank according to claim 2, wherein, The high-pressure gas tank is mounted on the vehicle in a posture in which a center of the intermediate portion extends in a vertical direction, The safety valve is mounted at the end of the upper side, The main pipe extends obliquely downward from the safety valve attached to the end portion and then extends along the intermediate portion.
5. 5. The safety device for a high-pressure gas tank according to claim 1, wherein, The high-pressure gas tank is provided at a position on the outer side in the vehicle width direction than the vehicle frame at a position on the rear side of the cab of the vehicle, The heat pipe is arranged in a space between the frame and the high-pressure gas tank.
6. 6. The safety device for a high-pressure gas tank according to claim 1, wherein, The high-pressure gas tank is arranged between a cab and a rear vehicle body of the vehicle, The heat pipe is arranged in a space between the rear vehicle body and the high-pressure gas tank.
7. 7. The safety device for a high-pressure gas tank according to claim 1, wherein, The safety device is provided with the safety valves respectively mounted on a plurality of the high-pressure gas tanks, The heat pipes include a common pipe thermally connected to each of the safety valves.
8. 8. The safety device for a high-pressure gas tank according to claim 7, wherein, The common pipe is provided to extend along a gas supply pipe connected to a plurality of the high-pressure gas tanks for delivering the high-pressure gas to a predetermined supply destination.
9. 9. The safety device for a high-pressure gas tank according to claim 7, wherein, The common pipe is provided so as to extend in the vehicle height direction and is connected to each of the safety valves respectively attached to the plurality of high-pressure gas tanks aligned in the vehicle height direction so as to be capable of conducting heat.
10. 10. The safety device for a high-pressure gas tank according to claim 7, wherein, The common pipe extends in the vehicle width direction and is connected to each of the safety valves mounted to the plurality of high-pressure gas tanks aligned in the vehicle width direction so as to be capable of conducting heat.
11. 11. The safety device for a high-pressure gas tank according to claim 1, wherein, The safety valve includes a sensing portion that opens a discharge port for discharging the high-pressure gas to the outside as the temperature rises, a housing that houses the sensing portion, and a first connection portion that is a hole or a groove formed in the housing at a position adjacent to the sensing portion, The heat pipe is connected with the first connecting part.
12. 12. The safety device for a high-pressure gas tank according to claim 1, wherein, The safety valve has a sensing portion that opens a discharge port for discharging the high-pressure gas to the outside as the temperature rises, and a housing that houses the sensing portion, The safety device further includes a collar formed of a material having a higher thermal conductivity than the housing and mounted to the housing, and the collar has a second connection portion which is a hole or a groove formed at a position adjacent to the sensing portion, The heat pipe is connected with the second connecting part.
13. 13. The safety device for a high-pressure gas tank according to claim 1, wherein, The safety device further includes a protection member formed in a plate shape or a lattice shape having a plurality of holes formed therein and covering the heat pipe.
14. 14. The safety device for a high-pressure gas tank according to claim 1, wherein, The vehicle is a fuel cell vehicle that drives a motor for running by using electric power of a fuel cell, The high-pressure gas tank is a hydrogen tank in which hydrogen gas is contained as the high-pressure gas.

Description

Safety device for high pressure gas tank Technical Field The present invention relates to a safety device for a high-pressure gas tank that accommodates therein a high-pressure gas as a fuel for a vehicle. Background Conventionally, there are vehicles that travel on a high-pressure gas as a fuel. For example, a fuel cell vehicle is known that travels using electric power generated by a chemical reaction between hydrogen gas and oxygen (air) as a high-pressure gas. A vehicle that uses such a high-pressure gas as a fuel is mounted with a high-pressure gas tank that accommodates the high-pressure gas therein. In general, a high-pressure gas tank mounted on a vehicle is provided with a safety valve that discharges high-pressure gas from the inside to the outside of the high-pressure gas tank as the temperature increases. As such a safety valve, for example, patent document 1 discloses a thermally operated overpressure preventing device that operates so that a part of hydrogen (high-pressure gas) compressed and filled in a hydrogen tank is released to the atmosphere in a short time when the internal temperature of the hydrogen tank (high-pressure gas tank) becomes equal to or higher than a predetermined temperature. Prior art literature Patent literature Patent document 1 Japanese patent laid-open No. 2022-88966 Disclosure of Invention Problems to be solved by the invention However, since the safety valve described above is operated (opened) by heat, there is a possibility that the operation is delayed or disabled when the temperature at a position apart from the safety valve increases. In particular, in commercial vehicles such as trucks and buses, since the high-pressure gas tank is enlarged, for example, even when a fire occurs in the vicinity of the high-pressure gas tank, the ignition position may be separated from the installation position of the safety valve, and it may be difficult to properly operate the safety valve. For this purpose, for example, it is considered that safety valves are attached to three or more positions including both end portions and an intermediate portion of the high-pressure gas tank so that the temperature increases in these positions can be handled. However, in this case, the manufacturing cost increases with the increase in the number of safety valves. In a vehicle in which a plurality of high-pressure gas tanks are provided separately from each other, even when there is a temperature rise in the vicinity of one high-pressure gas tank, it is desirable to operate a relief valve for the other high-pressure gas tank to release the high-pressure gas to the outside in order to prevent secondary damage. The present invention has been made in view of the above-described problems, and an object thereof is to provide a safety device for a high-pressure gas tank, which can more appropriately operate a safety valve. Means for solving the problems The present invention has been made to solve at least some of the above problems, and can be implemented as the following aspects or application examples. (1) The safety device for a high-pressure gas tank according to the present invention is a safety device for a high-pressure gas tank that accommodates high-pressure gas as fuel for a vehicle therein, and is provided with a safety valve that is attached to the high-pressure gas tank and that discharges the high-pressure gas from the inside of the high-pressure gas tank to the outside as the temperature increases, and a heat pipe that is connected to the safety valve and that moves heat by evaporation and condensation of a working fluid enclosed in the safety valve and capillary phenomenon of a wick (wick) provided on an inner wall. According to this aspect, the safety valve that discharges the high-pressure gas from the inside of the high-pressure gas tank to the outside as the temperature increases is connected to the heat pipe, so that heat can be transferred to the safety valve by the heat pipe that exhibits higher heat conductivity than stainless steel, copper, aluminum, or the like. Thus, for example, even when a fire occurs at a position distant from the safety valve, heat is quickly and efficiently moved from the fire position to the safety valve through the heat pipe, and therefore the safety valve operates with a rise in temperature, and high-pressure gas can be appropriately discharged. Therefore, according to the present embodiment, the safety valve can be made to operate more appropriately. That is, since the heat pipe having excellent heat conductivity is extended, the heat sensitivity to heat can be improved over a wide range and the temperature rise can be transmitted to the relief valve without increasing the number of the relief valves. Therefore, an increase in the number of safety valves can be suppressed, and therefore an increase in cost can be suppressed. Further, the heat pipe is a heat transfer device for transferring heat to the safety valve, and does not circulate hig