Thermal pressure relief device (TPRD), gas pressure tank and gas pressure tank system comprising TPRD and method for thermal excess pressure protection

Abstract

A gas pressure tank system is disclosed, and includes at least one gas pressure tank comprising a thermal pressure relief device. The thermal pressure relief device may include a valve unit fluidically connected to the at least one gas pressure tank and including at least one fluid path, by way of which a gas stored in the at least one gas pressure tank can be discharged into an environment. The valve unit may include a locking element which can be moved between an open position, in which the gas can flow through the fluid path, and a closed position, in which no gas can flow through the fluid path. The thermal pressure relief device may include a first trigger means configured to detect heat impact at least at one location of the gas pressure tank system spatially separated from the installation location of the thermal pressure relief device.

Claims

1. A gas pressure tank system for storing gaseous hydrogen, which is configured to supply a fuel cell system with gaseous hydrogen, comprising: at least one gas pressure tank comprising a connecting piece, and a thermal pressure relief device for the gas pressure tank system, wherein the thermal pressure relief device comprises: a valve unit which can be fluidically connected to the at least one gas pressure tank and which comprises at least one fluid path, by means of which a gas stored under pressure in the at least one gas pressure tank can be discharged into an environment, wherein the valve unit comprises a locking element which can be moved between an open position, in which the gas can flow through the fluid path, and a closed position, in which no gas can flow through the fluid path, and a first trigger means configured to move, due to heat impact, when reaching a predetermined temperature, the locking element into the open position and/or to enable the locking element to move into the open position, wherein the first trigger means is further configured to be able to detect heat impact at least at one location of the gas pressure tank system spatially separated from the installation location of the thermal pressure relief device, or to be able to detect heat impact at least at two spatially separated locations of the at least one gas pressure tank wherein the first trigger means is a test track which is under a predetermined pressure, so that the locking element, by application of this pressure, remains in the closed position until the pressure in the test track, due to the heat impact at the at least one location of the gas pressure tank system spatially separated from the installation location of the thermal pressure relief device, drops, or wherein the first trigger means is configured as a test track extending from the at least one location of the gas pressure tank system spatially separated from the installation location of the thermal pressure relief device to the thermal pressure relief device, the test track filled with a medium, the medium being a liquid or a gas, the pressure of which, due to heat impact, reaches a value when reaching the predetermined temperature, which is sufficient to move the locking element into the open position.

2. The gas pressure tank system according to claim 1, wherein the thermal pressure relief device is an on-tank valve configured to attach to the at least one gas pressure tank.

3. The gas pressure tank system according to claim 2, further comprising a connecting piece configured such that it can be screwed into the at least one gas pressure tank.

4. The gas pressure tank system according to claim 1, wherein the locking element is configured as a set piston movably mounted in the valve unit transversely to the fluid path.

5. The gas pressure tank system according to claim 4, wherein the set piston has an elongated cylindrical piston body, on the outer circumference of which three sealing members are provided spaced apart from each other in the longitudinal direction of the piston body, wherein a first chamber and a second chamber separated from each other in a gas-tight manner are formed in the valve unit by way of the set piston.

6. The gas pressure tank system according to claim 5, wherein in the closed position of the set piston the first chamber is fluidically connected to the fluid path and closes it, in the open position of the set piston the second chamber is fluidically connected to the fluid path and connects it to a relief port via a fluid pipe.

7. The gas pressure tank system according to claim 6, wherein the size of the second chamber is increased by a groove radially circumventing on the outer circumference of the piston body, such that the groove decreases a diameter of the piston body in a portion surrounded by the second chamber.

8. The gas pressure tank system according to claim 1, wherein the locking element is configured as a locking piston mounted in the valve unit so as to be movable in the direction of the fluid path or the outflow direction of the gas.

9. The gas pressure tank system according to claim 8, wherein the locking piston in the closed position closes a laterally disposed fluid pipe and in the open position releases it, whereby the fluid path is fluidically connected to the fluid pipe and thus fluidically connected to a relief port.

10. The gas pressure tank system according to claim 1, further comprising a second trigger means integrated into the valve unit and connected in parallel or in series to the first trigger means.

11. The gas pressure tank system according to claim 10, wherein at least one of the first trigger means and a second trigger means is a glass ampoule, respectively, configured such that it bursts or breaks when reaching the predetermined temperature.

12. The gas pressure tank system according to claim 11, wherein the test track is a hose or a pipe which is filled with a liquid or a gas that is under sufficiently high pressure, so that the locking element remains in the closed position until the pressure in the hose or the pipe drops due to heat impact.

13. The gas pressure tank system according to claim 12, wherein the test track comprises a detection element, the detection element comprising: the hose or pipe configured to at least partially fuse when reaching the predetermined temperature; selective weak points in the hose or pipe configured to fuse when reaching the predetermined temperature; sealing plugs inserted into the hose or configured to fuse when reaching the predetermined temperature; and/or glass ampoules configured to burst or break when reaching the predetermined temperature, and wherein the detection element is configured to open an opening in the hose or in the pipe.

14. The gas pressure tank system according to claim 13, wherein the detection element of the gas pressure tank system in which the thermal pressure relief device is installed is positioned at one or more locations most vulnerable to heat impacts.

15. The gas pressure tank system according to claim 12, wherein the at least one gas pressure tank is a hollow body formed of a multi-layer laminate, into which the connecting piece is incorporated, and wherein a hollow body hose or liquid pockets are incorporated into the hollow body, the a hollow body hose or liquid pocket configured to connect to the hose or the pipe of the first trigger means.

16. The gas pressure tank system according to claim 1, wherein the test track is a hose or, a pipe which is filled with a liquid configured to begin to boil when reaching the predetermined temperature, whereby the pressure in the hose or the pipe rises above a predetermined pressure, so that the locking element can be moved into the open position.

17. The gas pressure tank system according to claim 16, wherein when the hose or the pipe is filled with liquid, the liquid comprises any of water, ethanol, methanol, ethanol mixtures, and methanol mixtures.

18. The gas pressure tank system according to claim 1, wherein the locking element can be moved electrically.

19. The gas pressure tank system according to claim 1, wherein the gas pressure tank system is configured to receive control commands from an external source such that the first trigger means may be actuated by the external source.

20. The gas pressure tank system according to claim 1, further comprising an orientation detection device configured to detect in space the absolute geometric orientation of the valve unit, wherein the orientation detection device comprises at least one sensor selected from the group of: an accelerometer, a gyroscope and a terrestrial magnetic field sensor.

21. The gas pressure tank system according to claim 20, wherein the thermal pressure relief device is configured to select, based on an orientation of the valve unit determined by the orientation detection device, a relief port, by means of which a draining of the at least one connected gas pressure tank in a predetermined, spatial direction is possible.

22. A method for thermal excess pressure protection for gas pressure tank systems by means of a thermal pressure relief device comprising a first trigger means, comprising: opening of a fluid path, by means of which a gas pressure tank system can be drained when reaching a predetermined temperature due to heat impact, wherein heat impact can be detected for opening the fluid path at least at one location of the gas pressure tank system spatially separated from an installation location of the thermal pressure relief device, or heat impact can be detected for opening the fluid path at least at two spatially separated locations of the gas pressure tank system wherein the first trigger means is a test track which in an unactuated state is under a predetermined pressure and exerts this pressure on a locking element such that the latter remains in the closed position until the pressure in the test track, under heat impact, drops below a predetermined trigger pressure, whereby the first trigger means releases the locking element and the latter is moved into the open position, or wherein the first trigger means is a test track extending from the at least one location of the gas pressure tank system spatially separated from the installation location of the thermal pressure relief device to the thermal pressure relief device, the test track filled with a medium, the medium being a liquid or a gas, the pressure of which, due to heat impact, reaches a value when reaching the predetermined temperature, which is sufficient to move the locking element into the open position.

23. The method for thermal excess pressure protection according to claim 22, wherein the fluid path state is closed by means of a locking element when the test track is in the unactuated state, the locking element configured to be actively or passively moved from a closed position, in which no gas can flow through the fluid path, into an open position, in which gas can flow through the fluid path.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE FIGURES

(1) Further features and advantages of a device, a use and/or a method are apparent from the following description of embodiments with reference to the enclosed drawings. Of these drawings,

(2) FIG. 1 shows a schematic sectional view of a heat and pressure relief combination valve from the side according to the prior art,

(3) FIG. 2 shows a perspective view of a high-pressure vessel unit according to the prior art,

(4) FIG. 3 simplifies an embodiment of a gas pressure tank system according to the disclosure,

(5) FIG. 4 shows an enlarged section of the thermal pressure relief device of FIG. 3,

(6) FIG. 5 shows the locking element of the thermal pressure relief device of FIG. 4 in the closed position,

(7) FIG. 6 shows the locking element of the thermal pressure relief device of FIG. 4 in the open position, and

(8) FIG. 7 simplifies a further embodiment of a gas pressure tank system according to the disclosure, in particular a thermal pressure relief device according to the disclosure.

DETAILED DESCRIPTION

(9) Identical reference numbers specified in different figures designate identical, corresponding, or functionally similar elements.

(10) FIG. 1 shows a schematic sectional view of a heat and pressure relief combination valve 4 from the side according to the prior art. The valve 4 shown comprises a first housing 10 and a second housing 12. The first housing 10 has a first end 15, a second end 24 opposite the first end, and a pipe 22 extending from a second end 24 of the first housing 10 to the first end 15. The pipe 22 is positioned such that it leads into a distributor 3 and fluidically communicates therewith.

(11) The first and second housings 10, 12 define a chamber 20. The second housing 12 preferably has an opening 34 so that, when the second housing 12 is accommodated by the first housing 10, the openings 14, 34 of the first and second housings together define the chamber 20 adjacent to the pipe 22.

(12) A bearing member 30, a spring 32 and a heat element 34 are disposed in the chamber 20. The bearing member 30 is disposed adjacent to the pipe 22. A part 36 of the bearing member 30 is made of a sealing material disposed adjacent to the pipe 22. The remaining part of the bearing member 30 acts as a bearing surface on which a force is exerted by the spring 22.

(13) It should be noted that the bearing member 30 is formed such that while it acts as a seal against the pipe 22, it does not act as a seal in the chamber 22. Under normal conditions, when the valve 4 is in an unactuated state, the spring 32 is supported under compression against the bearing member 30. Thus, under normal conditions, the spring 32 pretensions the bearing member 30 against the pipe 22. The bearing member thus acts as a seal between the pipe 22 and the chamber 20.

(14) The mode of operation of the valve is now described; as already explained, the valve 4 is integrated into the opening 6 in the distributor 3 which is mounted on the vessel 2 containing a gaseous or liquid fluid. Under normal conditions, the spring 32 is under compression and exerts a force against the bearing member 30 so as to form a seal between the pipe 22 and the chamber 20. Thus, under normal conditions, the spring 32 pretensions the bearing member 30 against the pipe 22. The heat element 34 is disposed aligned with the spring 32.

(15) The heat element 34 has a fusion point which causes it to fuse or lose its solid state properties when a predetermined temperature is reached in the vessel 2. When this occurs, the heat element fuses and causes the spring 32 to decompress into the area previously occupied by the heat element 34. When the spring 32 relaxes, the bearing member 30 is no longer pretensioned against the pipe 22. Thus, it is possible for the excessive heat pressure to pass from the pipe 22 into the chamber 20 and to escape through the exit pipe 42. The valve 4 therefore provides heat relief and prevents damage to the vessel and/or the fluid.

(16) FIG. 2 shows a perspective view of a high-pressure vessel unit 10 according to the prior art. The high-pressure vessel unit 10 shown comprises a box-like housing 22, a plurality of cylindrical vessels 18 lined up inside the housing 22, wherein each vessel 18 has an opening 30B at an end portion on one side in the axial direction, a coupling element 20 which connects the openings 30B so as to couple the plurality of vessels 18 to each other and which contains a flow passage that connects the interiors of the plurality of vessels 18 to communicate with each other. The described high-pressure vessel unit 10 further comprises an outflow pipe 32 which leads from the coupling element 20 through a through hole 46A formed in the housing 22 to the exterior of the housing 22, wherein a valve 34 is connected to the outflow pipe 32, which can open and close the flow passage.

(17) In the shown high-pressure vessel unit 10 according to the prior art, a thermal pressure relief device is only integrated in the valve 34 for cost reasons; accordingly, it is possible here to detect heat impact only outside the housing 22 and only at one location of the high pressure vessel unit 10, which is not satisfactory.

(18) FIG. 3 shows, in a simplified manner, a first embodiment of a gas pressure tank system 400 according to the disclosure, which consists, by way of example, of two gas pressure tanks 300, two on-tank valves 200 which are each screwed into a gas pressure tank 300, and a thermal pressure relief device 100 integrated in a gas handling unit in the embodiment shown. The thermal pressure relief device 100 includes a connecting piece 112 having external threads 114, configured to couple to a connecting piece 211 of the gas pressure tank 300 having internal threads 212. Accordingly, the valve unit 110 of the thermal pressure relief device 100 comprises not only the components necessary for thermal pressure monitoring of the gas pressure tank system 400, but also further components, such as a safety valve, a pressure control valve, filters, check valves, and the like.

(19) As can be seen from FIG. 3, the shown thermal pressure relief device 100 in the valve unit 110 comprises a fluid path 101 which is fluidically connected to or communicates with the two gas pressure tanks (high-pressure vessels) 300, in particular their content, the fuel. A locking element 111 is provided in the fluid path 101, which can open and close the fluid path. In the closed position, which corresponds to the basic position, no gas, in particular fuel, can flow through the fluid path, and thus the gas pressure tanks 300 are in the operational state. However, should a first trigger means 120 of the thermal pressure relief device now detect that heat impact in the form of a fire occurs at the location St2, for example, the trigger means 120 can enable the locking element 111 to move into the open position, whereby the fluid path 101 is connected to the second fluid path 102 (fluid pipe), whereby the gas (the fuel) can be drained or discharged from the gas pressure tanks 300 via a relief port A3 of the valve unit into the environment of the thermal pressure relief device in a controlled manner.

(20) In the embodiment shown, the locking element 111 is configured as a set piston 111a, the function of which will be described in more detail later with reference to FIG. 4. The first trigger means 120 is configured as a test track which here comprises a distributor to which a plurality of hoses and/or pipes 122 can be connected in order to realize the test track. As shown here, two hoses 122 are connected to the distributor, which are each laid to one of the gas pressure tanks in order to be able to detect possible heat impact there at the locations or areas St2 and St3. Moreover, a pipe is connected to the distributor, which leads to the location or the area St4 that can be provided in the engine compartment of a vehicle or in the vicinity of brakes of the vehicle, for example.

(21) In the embodiment shown, the test track is filled with a liquid, preferably water, and pressurized. The pressure prevailing in the test track is led to the set piston 111a which is thereby pushed into the closed position against the force of a spring; in this state, the test track is hermetically or watertightly closed.

(22) If heat impact now occurs at one of the locations St2 to St4, for example a sealing plug formed of plastic in the pipe or in one of the hoses of the test track is fused and the pressurized water can escape, whereby the pressure in the test track or in the first trigger means drops and the spring can thus shift or push the set piston 111a into the open position, whereby the gas can escape through the relief port A3.

(23) FIG. 4 shows an enlarged section of the thermal pressure relief device 100 of FIG. 3. As illustrated in FIG. 4, the set piston 111a is movably mounted in the valve unit 110 transversely to the fluid path 101, in particular movably mounted in the transverse direction (perpendicularly) to the fluid path 101. The set piston 111a has an elongated cylindrical piston body, on the outer circumference of which three sealing members 113 are provided in grooves. The three sealing members 113 are disposed spaced apart from each other in the longitudinal direction of the piston body, i.e., perpendicularly to the fluid path 101, whereby two chambers K1, K2 separated from each other in a gas-tight manner are formed in a guide hole in which the set piston 111a is movably accommodated.

(24) FIG. 5 shows the locking element 111a of the thermal pressure relief device 100 of FIG. 4 in the closed position. As can be seen from FIG. 5, a pressure P1 prevailing in the test track (first trigger means) 120 is applied to the left side of the set piston 111a and pushes the set piston to the right against a spring 114 which is pretensioned thereby. In this position, the fluid path 101 opens into the first chamber K1 which is not connected to the second fluid path 102, which is why the thermal pressure relief device is in the closed state, i.e., in the unactuated state.

(25) FIG. 6 shows the locking element or the set piston 111a of the thermal pressure relief device 100 of FIG. 4 in the open position, i.e., in the actuated state. As can be seen from FIG. 6, the pressure in the test track has dropped to a pressure D2 which is lower than the pressure P1, whereby the pretensioned spring 114 can shift the set piston 111a to the left into the open position. In this position, the fluid path 101 opens into the second chamber K2 which is connected to the second fluid path 102, whereby the gas can escape from the gas pressure tank outwards into the environment via the relief port A3. As can further be seen from FIG. 6, a groove is formed or the diameter of the set piston 111a is reduced at the location of the chamber K2, i.e., between the two right sealing members 113, in order to ensure a sufficiently high flow rate of the outflowing gas.

(26) FIG. 7 shows, in a simplified manner, a further embodiment of a gas pressure tank system according to the disclosure, in particular of an alternative thermal pressure relief device according to the present disclosure. In its fundamental structure, the gas pressure tank system shown in FIG. 7 corresponds to the system already described in FIG. 3. In the embodiment shown here, only the locking element 111 is not configured as a set piston 111a, but as a locking piston 111b.

(27) As can be seen from FIG. 7, the locking piston 111b is movably accommodated in the valve unit 110 in the direction of the fluid path 101 or in the direction of the gas flowing out through the fluid path 101. On the side facing the fluid path 101, the locking piston 111b has a conical valve body area which in the closed state comes into contact with a valve seat, whereby the thermal pressure relief device 100 is in the closed state. On the side of the locking piston 111b facing away from the valve seat, a piston area is formed which is significantly larger than the valve seat area, for example 50 to 100 times as large. In this way, the pressure of 10 to 20 bar prevailing in the test track is sufficient to close the valve against the cylinder pressure of up to 1000 bar applied to the fluid path 101.

(28) If the pressure in the test track now drops due to heat impact, as in the embodiment described above, the pressure acting on the piston area drops and the locking piston 111b is shifted upwards by the pressure prevailing in the gas pressure tank and applied to the fluid path 101 and opens the valve, whereby the gas can flow to the relief port A3 via the second fluid path 102. In order to ensure opening of the valve even at a relatively low pressure in the gas pressure tank 300, a spring can be provided which pushes the locking piston 111b away from the valve seat if the pressure in the test track drops due to heat impact.

(29) It is apparent to the skilled person that individual features described in different embodiments can also be implemented in a single embodiment, provided they are not structurally incompatible. Likewise, various features described in the context of a single embodiment may also be provided in several embodiments either individually or in any suitable sub-combination.

LIST OF REFERENCE NUMBERS

(30) 100 thermal pressure relief device 101 fluid path 102 fluid pipe (second fluid path) 110 valve unit 111 locking element 111a set piston 111b locking piston 112 connecting piece 114 external threads 113 sealing member(s) 120 first trigger means 122 hoses and/or pipes 121 detection element (opening element) 130 second trigger means 140 communication device 150 orientation detection device A3 relief port K1 first chamber K2 second chamber St1 installation location St2 (first) further location St3 (second) further location 200 on-tank valve 201 temperature and/or pressure detection unit 204 safety valve 205 excess flow valve 206 filter 207 refueling channel 212 internal threads 211 connecting piece 300 gas pressure tank 301 connecting piece 302 temperature sensor 400 gas pressure tank system

(31) The present application claims priority to International Patent Application No. PCT/EP2021/065627 filed on Jun. 10, 2021 and German Patent Application No. 10 2020 207 261.2 filed on Jun. 10, 2020, the entire contents of which are incorporated herein by reference, in their entirety.

(32) In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.