Shut-off valve device for a fuel supply system for supplying an internal combustion engine with hydrogen, pressure regulating device for such a fuel supply system, and fuel supply system

Abstract

The invention relates to a shut-off valve device (32) for a fuel supply system (10) for supplying gaseous fuel from a high-pressure tank (12) to a consumer, for example an internal combustion engine, comprising a tank-side inlet (54), a consumer-side outlet (56), a fluid connection (51) which connects the inlet (54) to the outlet (56) and in which a shut-off valve (58) is arranged, which shut-off valve has a displaceable valve element (82) for opening and closing the shut-off valve (82), characterised in that the shut-off valve device (32) furthermore has a control space (84) in which a control-space-side fluid pressure prevails, and the control space (84) is coupled to the valve element (82) in such a manner that the control-space-side fluid pressure acts on the valve element (82) in an opening direction, and the control space (82) can be fluidically connected selectively to either the inlet (52) or the outlet (56) via a control line (53) in which an actuator-controllable control valve (64, 64.1, 64.2, 64.3) is provided, in order to open the shut-off valve (58) when the control space (84) is fluidically connected to the inlet (54) and in order to close the shut-off valve (58) when the control space (84) is fluidically connected to the outlet (56).

Description

[0001] Description

[0002] title an internal combustion engine with hydrogen. for such a

[0003] State of the art

[0004] From DE 10 2016 205 713 A1 a pressure control system for a gas-powered internal combustion engine is known. The pressure control system comprises a pressure regulator for setting a constant gas pressure and a shut-off valve.

[0005] From DE 10 2021 212 129 A1 a shut-off valve for a hydrogen tank system is known, which comprises a main valve and a control valve.

[0006] From DE 10 2020 201 178 A1, a shut-off valve for interrupting an air supply to a fuel cell stack is known, which comprises a valve piston which, depending on its axial position, establishes or interrupts a connection between an air inlet and an air outlet and which also delimits a control chamber which can be connected to the air inlet channel via a control valve.

[0007] Disclosure of the invention

[0008] The invention is based on the desire to provide a shut-off valve device for a fuel supply system for supplying gaseous fuel from a high-pressure tank to a consumer, for example an internal combustion engine, which on the one hand can have a comparatively large diameter in the open state and thus leads to only a small pressure drop in the fuel supply system. On the other hand, however, the shut-off valve should be able to be opened or closed as a result of comparatively low magnetic forces despite the high pressures, so that the shut-off valve itself as well as its control and the components that control it can be simplified.

[0009] The gaseous fuel could be hydrogen, for example. The high pressure could be 700 bar, for example.

[0010] The problem underlying the invention is solved in that the shut-off valve device has a tank-side inlet and a consumer-side outlet as well as a fluid connection connecting the inlet to the outlet, in which a shut-off valve is arranged, which has a displaceable valve element for opening and closing the shut-off valve.

[0011] The inlet may, for example, be an inlet nozzle which is detachably or permanently connected, for example screwed or welded, to a housing of the shut-off valve device, in particular a housing which is formed in one piece.

[0012] The outlet may, for example, be an outlet nozzle which is detachably or permanently connected, for example screwed or welded, to the housing of the shut-off valve device, in particular a one-piece housing.

[0013] The fluid channel can, for example, run through the housing mentioned above, from nozzle to nozzle.

[0014] According to the invention, it is further provided that the shut-off valve device further comprises a control chamber in which a control chamber-side fluid pressure prevails, and the control chamber is coupled to the valve element in such a way that the control chamber-side fluid pressure acts on the valve element in the opening direction, and the control chamber can be fluidically connected either to the inlet or to the outlet via a control line in which at least one actuator-controllable control valve is provided, in order to open the shut-off valve when the control chamber is fluidically connected to the inlet, and to close the shut-off valve when the control chamber is fluidically connected to the outlet.

[0015] The function of the invention is based on the assumption that an increased or increaseable gas pressure can be assumed on the inlet side of the shut-off valve device within the fuel supply system. If the gas pressure in the control chamber of the shut-off valve device is equalized with the gas pressure on the inlet side of the shut-off valve device by appropriately controlling the control valve, i.e., increased, this forces the valve element of the shut-off valve in its opening direction.

[0016] On the outlet side of the shut-off valve device, on the other hand, a reduced or reducible gas pressure can be assumed within the fuel supply system. If the gas pressure in the control chamber of the shut-off valve device is equalized with this reduced gas pressure on the outlet side of the shut-off valve device by appropriately controlling the control valve, i.e., reduced, the valve element of the shut-off valve closes.

[0017] The opening and closing of the shut-off valve is therefore initiated by the control valve. Since the control line in which it is located serves only to equalize pressure between the control chamber and the inlet and outlet sides, the control valve can be selected to have a relatively small flow diameter. The magnetic forces required to open and close it can then also be small, even if the shut-off valve has a large flow diameter and high forces act on the valve element in the opening and closing directions.

[0018] Connecting the control chamber to the outlet side of the shut-off valve device for closing the shut-off valve has the further advantage that the gaseous fuel in the control chamber remains in the fuel supply system even when the shut-off valve is closed, i.e. it is still available for combustion at a later time and does not enter the surrounding area, thus cannot cause any hazards there.

[0019] The at least one actuator-controlled control valve can be a single actuator-controlled control valve, for example an actuator-controlled three-way valve that can optionally connect its input to one of its two outputs.

[0020] The at least one actuator-controlled control valve can alternatively be two (or more) actuator-controlled control valves, for example two (or more) switching valves.

[0021] For example, the control chamber can be fluidically connected either to the inlet or to the outlet via a three-way valve.

[0022] The three-way valve can be controlled by an actuator and installed in such a way that it fluidically connects the control chamber to the outlet when de-energized, and fluidically connects the control chamber to the outlet when energized. This ensures that the state in which the three-way valve is de-energized causes the shut-off valve to close, thus preventing any further supply of gaseous fuel from the high-pressure tank to the consumer. Since a fault in the fuel supply system potentially leads to the three-way valve no longer being energized, the fuel supply system is thus intrinsically safe.

[0023] Alternatively, the control chamber can be fluidically connected to the inlet via a normally closed switching valve or via several normally closed switching valves connected in series. Additionally, the control chamber can be fluidically connected to the outlet via another normally open switching valve. Similar to the alternative with a three-way valve, this arrangement ensures the intrinsic safety of the fuel supply system.

[0024] The coupling of the control chamber to the valve element can be achieved by delimiting the control chamber by a displaceable piston, wherein the piston is coupled to the valve element in such a way that a displacement of the piston, which is accompanied by an enlargement of the control chamber, opens the shut-off valve and a displacement of the piston, which is accompanied by a reduction of the control chamber, closes the shut-off valve.

[0025] In this case, the area over which the piston is pressurized on the control chamber side can be larger than the area over which the valve element is pressurized from the inlet side when the shut-off valve is closed. This allows high opening and closing forces to be generated on the shut-off valve, enabling its high tightness.

[0026] In the case of the area with which the piston is pressurised on the control chamber side and the area with which the valve element is pressurised from the inlet side when the shut-off valve is closed, in cases where these areas are not geometrically perpendicular to the direction of movement of the piston, the effective areas must be assumed for the above-mentioned areas, as is self-evident to the expert in the field of pneumatics.

[0027] The coupling of the control chamber with the valve element can in principle also be achieved in another way, for example by using a flexible membrane instead of the movable piston.

[0028] Different configurations of the shut-off valve are basically possible.

[0029] Advantageously, the valve element of the shut-off valve can be subjected to a fluid pressure on the inlet side in the closing direction and a fluid pressure on the outlet side in the opening direction. This improves the tightness of the shut-off valve.

[0030] Advantageously, a valve spring can be provided, whereby the valve element of the shut-off valve is urged in the closing direction by the valve spring. This improves the tightness of the shut-off valve.

[0031] It can be provided that, when the shut-off valve is closed, the valve spring exerts a closing force on the valve element that is greater than the opening force that an electric actuator of the at least one control valve can exert on a control valve element of the at least one control valve. The high shut-off force then ensures a high level of tightness of the shut-off valve, and although only small forces need to be transmitted by the actuator of the control valve, forces act via the piston of the shut-off valve device that are large enough to overcome the comparatively large closing force generated by the valve spring.

[0032] The shut-off valve device according to the invention operates particularly effectively within a pressure control device for a fuel supply system for supplying gaseous fuel from a high-pressure tank to a consumer, wherein the pressure control device has an electrically controllable pressure reducing device which is arranged fluidically between the inlet and the outlet in the fluid connection, because it is precisely through the pressure reduction effected within the pressure control device that the initially mentioned reduced or reducible gas pressure on the outlet side of the shut-off valve device or the increased or increaseable gas pressure on the inlet side of the shut-off valve device can be effected.

[0033] The electrically controllable pressure reducing device can, for example, comprise a proportional valve or a plurality of proportional valves connected in parallel, which is / are arranged fluidically between the inlet and the outlet in the fluid connection.

[0034] The pressure control device may further comprise a pressure sensor that fluidically senses a pressure in the fluid connection between the inlet and the outlet.

[0035] The invention also relates to a fuel supply system with such a pressure control device and with a high-pressure tank upstream of the pressure control device and with a fuel distributor and at least one injector fluidly connected thereto downstream of the pressure control device. Embodiments of the present invention are explained below with reference to the accompanying drawings. In these:

[0036] Figure 1 is a schematic representation of a

[0037] Fuel supply system for supplying an internal combustion engine with gaseous fuel, with a pressure control device which in turn comprises a shut-off valve device;

[0038] Figure 2 is a perspective view of a first embodiment of the pressure control device of Figure 1;

[0039] Figure 3 is a perspective view of a second embodiment of the pressure control device of Figure 1;

[0040] Figure 4 is a hydraulic equivalent circuit diagram of the pressure control device of Figure 1;

[0041] Figure 5 shows an alternative to the embodiment shown in Figure 4.

[0042] A fuel supply system is designated overall by reference numeral 10 in Figure 1. It serves to supply an internal combustion engine (not shown) with gaseous hydrogen.

[0043] The hydrogen is stored under high pressure, for example, 700 bar, in a high-pressure tank 12. This can be filled via a filling connection 14. Furthermore, an integrated unit 16 consisting of a tank valve for filling and dispensing hydrogen into and from the high-pressure tank 12 and a temperature sensor for detecting the temperature of the gaseous hydrogen coming from the high-pressure tank 12 is arranged on the high-pressure tank 12. The gaseous hydrogen is fed via a pressure line 18, first to a filter 20 and from there to a high-pressure pressure regulator 22. This reduces the pressure of the gaseous hydrogen to a pressure of, for example, 40 bar. The pressure line 18 leads from the high-pressure pressure regulator 22 to a pressure sensor 24, a further filter 26, and an optional temperature control device 28, finally to a low-pressure pressure regulator 30.

[0044] The low-pressure pressure control device 30 comprises a shut-off valve device 32, downstream of which are two hydraulically parallel pressure control valves 34, and a low-pressure pressure sensor 35 between the shut-off valve device 32 and the two pressure control valves 34. The two pressure control valves 34 are identically constructed proportional valves. The low-pressure pressure control device 30 further reduces the pressure in the pressure line 18, for example, from 40 bar on the inlet side to 15 bar on the outlet side. The shut-off valve device 32 upstream of the pressure control valves 34 is closed when the fuel supply system 10 is not in operation. This reliably prevents unwanted gas leakage.

[0045] Downstream of the low-pressure pressure regulator 30, the pressure line 18 leads to a distribution chamber 36, which can be designed, for example, as an elongated tube similar to a typical fuel rail, as is known from gasoline and diesel fuel systems. The gas pressure prevailing in the distribution chamber 36 is detected by a pressure sensor 37.

[0046] Connected to the distribution chamber 36 are several injectors 38, which, in this example, inject the gaseous hydrogen directly into combustion chambers 40 of the internal combustion engine. The gaseous hydrogen is mixed with atmospheric oxygen in the combustion chambers 40, and this mixture is ignited by a respective ignition device 42. Typically, the internal combustion engine is a 4-stroke piston internal combustion engine.

[0047] For example, such an internal combustion engine is used to power a motor vehicle. However, it can also be used stationary, for example, to drive a generator to generate electricity. The fuel supply system 10 and its components are controlled by an electronic control and regulating device 44, which has one or more corresponding microprocessors, a memory for program code, etc. This receives signals from, among others, the temperature sensor 16, the pressure sensor 24, the pressure sensor 37, etc. The control and regulating device 44 controls various components of the fuel supply system 10, including the low-pressure pressure regulating device 30 and the ignition devices 42. Furthermore, a control device 46 is also controlled by the control and regulating device 44, which in turn specifically controls or regulates the operation of the fuel storage device 12.

[0048] The low-pressure pressure regulator 30 is shown in a first embodiment in Figure 2 (unlike Figure 1) with a single pressure regulator valve 34. The low-pressure pressure regulator 30 includes a housing 48 with an inlet-side connection piece 50 and an outlet-side connection piece 52. The housing 48 integrates the pressure regulator valve 34, the shut-off valve device 32, and the low-pressure pressure sensor 35 into a single structural unit. The housing 48 can be a milled aluminum block. In the low-pressure pressure regulator 30 shown in Figure 3, which is a second embodiment, two pressure regulator valves 34 are present, corresponding to Figure 1, which are connected in parallel.

[0049] An exemplary design of the low-pressure pressure control device 30 or the shut-off valve device 32 from the preceding Figures 1 to 3 is shown in detail in Figure 4.

[0050] Accordingly, the low-pressure pressure control device 30 or the shut-off valve device 32 extends from a tank-side inlet 54, which is designed as an inlet nozzle 50, to a consumer-side outlet 56, which is designed as an outlet nozzle 52.

[0051] The inlet connection 50 and the outlet connection 52 can be detachably or permanently connected, for example, screwed or welded, to the housing 48 (see Figures 2 and 3), which is particularly formed in one piece, of the low-pressure pressure control device 30 or the shut-off valve device 32. A fluid connection 51 extends from the inlet connection 50 to the outlet connection 52, in which a shut-off valve 58 of the shut-off valve device 32 and, in the example, an electrically controllable pressure reducing device in the form of a pressure control valve 34 are arranged fluidically downstream thereof.

[0052] The shut-off valve 58 comprises a valve element 82, which is displaceable in the vertical direction in Figure 4, and a valve seat 116 against which the valve element 82 rests in the closed position of the shut-off valve 58. The valve element 82 is acted upon in the closing direction by an inlet-side pressure and by a valve spring 62 of the shut-off valve 58, and is acted upon in the opening direction by an outlet-side pressure.

[0053] The shut-off valve device 32 further comprises a control chamber 84 in which a control-chamber-side fluid pressure prevails. The control chamber 84 is coupled to the valve element 82 in such a way that the control-chamber-side fluid pressure acts on the valve element 82 in an opening direction of the shut-off valve 58.

[0054] For this purpose, the control chamber 84 is delimited by a displaceable piston 86, wherein the piston 86 is coupled to the valve element 82 in such a way that a displacement of the piston 86, which is accompanied by an enlargement of the control chamber 84 (upward in Figure 4), opens the shut-off valve 58. A displacement of the piston 86, which is accompanied by a reduction of the control chamber 84 (downward in Figure 4), closes the shut-off valve 58.

[0055] The piston 86 and the valve element 82 can, for example, be rigidly coupled to each other via a rod-like connection 89, as indicated in Figure 4. Other coupling implementations are possible.

[0056] In the example, the control chamber 84 is connectable to the inlet 54 via a first control valve 64.1 and a first branch line. In the example, the control chamber 84 is connectable to the outlet 56 via a second control valve 64.2 and a second branch line. The first control valve 64.1 is a normally closed switching valve, and the second control valve 64.2 is a normally open switching valve. If the first control valve 64.1 and the second control valve 64.2 are energized, the first control valve 64.1 opens and the second control valve 64.2 closes, and the inlet-side fluid pressure builds up in the control chamber 84. A resulting upward displacement of the piston 86 in Figure 4 also displaces the valve element 82 in this direction, so that the shut-off valve 58 opens. This enables the supply of gaseous fuel from the tank 12 to the consumer.

[0057] If, however, the first control valve 64.1 and the second control valve 64.2 are de-energized, the first control valve 64.1 closes and the second control valve 64.2 opens, and any fluid pressure present in the control chamber 84 is reduced by diverting the gaseous fuel through the outlet 56. A resulting downward displacement of the piston 86 in Figure 4 also displaces the valve element 82 in this direction, causing the shut-off valve 58 to close. This ensures that no more gaseous fuel reaches the consumer from the tank 12.

[0058] In an alternative not shown, two first control valves 64.1 can be provided instead of the first control valve 64.1. These are switching valves connected directly one after the other and closed when de-energized. The shut-off function is then ensured even if one of the two first control valves 64.1 fails to close when de-energized.

[0059] In an alternative, which can be seen from Figure 5, in contrast to the design explained above with reference to Figure 4, the first control valve 64.1 and the second control valve 64.2 can be replaced by a three-way valve 64.3, which can be controlled by an actuator and fluidically connects the control chamber 84 to the outlet 56 in the de-energized state and fluidically connects the control chamber 84 to the inlet 54 in the energized state. In this case, too, an additional (not shown) normally closed switching valve can be provided between the inlet 54 and the three-way valve 64.3 for safety purposes.

Claims

Claims 1 . Shut-off valve device (32) for a fuel supply system (10) for supplying gaseous fuel from a high-pressure tank (12) to a consumer, for example an internal combustion engine, comprising a tank-side inlet (54), a consumer-side outlet (56), a fluid connection (51) connecting the inlet (54) to the outlet (56), in which a shut-off valve (58) is arranged, which has a displaceable valve element (82) for opening and closing the shut-off valve (58), characterized in that the shut-off valve device (32) further has a control chamber (84) in which a control chamber-side fluid pressure prevails, and the control chamber (84) is coupled to the valve element (82) in such a way that the control chamber-side fluid pressure acts on the valve element (82) in an opening direction, and the control chamber (82) is connected via a control line (53) in which at least one actuator-controllable control valve (64, 64.1 , 64.2, 64.3) is provided, is optionally fluidically connectable either to the inlet (54) or to the outlet (56) in order to open the shut-off valve (58) when the control chamber (84) is fluidically connected to the inlet (54) and to close the shut-off valve (58) when the control chamber (84) is fluidically connected to the outlet (56).

2. Shut-off valve device (32) according to claim 1, characterized in that the control chamber (84) is fluidically connected to the outlet (56) and is fluidically separated from the inlet (54) when the at least one actuator-controllable control valve (64, 64.1, 64.2, 64.3) is de-energized.

3. Shut-off valve device (32) according to claim 1 or 2, wherein the control chamber (84) is delimited by a displaceable piston (86), wherein the piston (86) is coupled to the valve element (82) in such a way that a displacement of the piston (86), which is accompanied by an enlargement of the control chamber (84), opens the shut-off valve (58) and a displacement of the piston (86), which is accompanied by a reduction of the control chamber (84), closes the shut-off valve (58).

4. Shut-off valve device (32) according to claim 3, wherein the area with which the piston (84) is pressurized on the control chamber side is larger than the area with which the valve element (82) is pressurized from the inlet side when the shut-off valve is closed.

5. Shut-off valve device (32) according to one of the preceding claims, wherein the valve element (82) is acted upon in the closing direction by an inlet-side fluid pressure and is acted upon in the opening direction by an outlet-side fluid pressure and is acted upon in the closing direction by a valve spring (62) of the shut-off valve device (32).

6. Shut-off valve device (32) according to claim 5, wherein the valve spring (62) exerts a closing force on the valve element (82) when the shut-off valve (58) is closed, which closing force is greater than an opening force that an electrical actuator of the at least one control valve (64, 64.1, 64.2, 64.3) is capable of exerting on a control valve element of the at least one control valve (64, 64.1, 64.2, 64.3).

7. Shut-off valve device (32) according to one of the preceding claims, wherein the control chamber (84) is fluidically connectable to the inlet (54) via a normally closed switching valve (64, 64.1).

8. Shut-off valve device (32) according to one of the preceding claims, wherein the control chamber (64) is fluidically connectable to the inlet (54) via two normally closed switching valves (64, 64.1) connected in series.

9. Shut-off valve device (32) according to one of the preceding claims, wherein the control chamber (84) is fluidically connectable to the outlet (56) via a normally open switching valve (64, 64.2).

10. Shut-off valve device (32) according to one of the preceding claims, wherein the control chamber (84) is fluidically connectable via a three-way valve (64, 64.3) either to the inlet (54) or to the outlet (56).

11. Shut-off valve device (32) according to the preceding claim, wherein the three-way valve (64, 64.3) is actuated and, in the de-energized state, fluidically connects the control chamber (84) to the outlet (56).

12. Pressure control device (30) for a fuel supply system (10) for supplying gaseous fuel from a high-pressure tank (12) to a consumer, for example an internal combustion engine, comprising a shut-off valve device (32) according to one of the preceding claims and an electrically controllable pressure reducing device (34) which is fluidically arranged in the fluid connection (51) between the inlet (54) and the outlet (56).

13. Pressure control device (30) according to claim 12, wherein the electrically controllable pressure reducing device (34) comprises a proportional valve which is fluidically arranged in the fluid connection (51) between the inlet (54) and the outlet (56).

14. Pressure control device (30) according to claim 12 or 13, wherein the pressure control device (30) comprises a pressure sensor (35) which fluidically senses a pressure in the fluid connection (51) between the inlet (54) and the outlet (56).

15. A fuel supply system (10) comprising a shut-off valve device (32) according to any one of claims 1 to 11 or a pressure regulating device (30) according to any one of claims 12 to 14; and comprising a high-pressure tank (12) upstream of the shut-off valve device (32) or the pressure regulating device (30); and further comprising a fuel distributor (26) and at least one injector (38) fluidly connected thereto downstream of the shut-off valve device (32) or the pressure regulating device (30).

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