Shut-off valve and hydrogen tank system equipped with shut-off valve

Abstract

The present invention relates to a shut-off valve (1) for a hydrogen tank system, the shut-off valve (1) having a housing (2) in which an annular electromagnetic coil (3) is received for acting on a magnetic armature (4) configured as a flat armature of a control valve (5) and on a magnetic armature (6) configured as a cylindrical armature of a main valve (7), the two magnetic armatures (4, 6) being arranged coaxially and together defining a control chamber (8) formed in the magnetic coil (3), the control chamber (8) being pneumatically connected on the one hand to a control valve chamber (9) and on the other hand to a main valve chamber (10), and at least one spring (11, 12) for resetting the two magnetic armatures (4, 6) is received in the control chamber (8). The present invention further relates to a hydrogen tank system equipped with a shut-off valve (1) according to the present invention.

Description

[Technical field]

[0001] The present invention relates to a shut-off valve for a hydrogen tank system.The present invention further relates to a hydrogen tank system equipped with a shut-off valve according to the invention. [Background technology]

[0002] Hydrogen tank systems for automobiles or mobile hydrogen tank systems used to supply hydrogen to fuel cells or internal combustion engines are known. In order to avoid uncontrolled release of hydrogen in the event of a malfunction, such as a line break or an accident, the individual containers of the hydrogen tank system must each be closable by a shut-off valve. The shut-off valves used must therefore be configured as valves that close automatically in the absence of current.

[0003] Currentless automatic shut-off valves are known from the prior art, which have a main valve that is servo-controlled, i.e. indirectly controlled via a control valve. The control chamber defined by the valve member of the main valve is depressurized by opening the control valve. This also relieves the load on the valve member, resulting in a pressure compensation that creates a pneumatic force balance. The main valve can be opened using the spring force of a spring or the magnetic force of a magnet armature. Closing of the main valve can likewise be brought about by a spring force or a magnetic force. However, it has been found that this generally has the disadvantage of requiring more space for installation, since large strokes, which also require larger and / or more magnet armature elements, increase the space required for installation and the costs.

[0004] The space provided in a mobile hydrogen tank system is limited. This is especially true for hydrogen tank systems having a pressurized gas container with a narrow portion in which a shutoff valve is to be installed, because the narrow portion forms a sturdy and therefore reliable installation portion. Therefore, a shutoff valve having a small installation space requirement is required. Summary of the Invention [Problem to be solved by the invention]

[0005] The object of the present invention is therefore to provide a miniaturized shut-off valve for hydrogen tank systems, which allows a large stroke with only one small magnet armature due to optimized magnetic flux line guidance. [Means for solving the problem]

[0006] To achieve this object, a shut-off valve is provided having the features of claim 1. Preferred embodiments of the invention are set forth in the dependent claims. Furthermore, a hydrogen tank system is provided which comprises at least one shut-off valve according to the invention.

[0007] A shut-off valve for a hydrogen tank system is proposed, which has a housing in which an annular electromagnetic coil is received for acting on a magnetic armature configured as a flat armature of the control valve and on a magnetic armature configured as a cylindrical armature of the main valve. The two magnetic armatures are arranged coaxially and together define a control chamber formed in the magnetic coil, which is pneumatically connected on the one hand to the control valve chamber and on the other hand to the main valve chamber. At least one spring is received in the control chamber for resetting the two magnetic armatures. Effect of the Invention

[0008] Therefore, the proposed shut-off valve is a servo-controlled solenoid valve. When the main valve opens, the magnetic and pneumatic forces create a pressure and thus a force ratio on the magnet armature of the main valve that changes with the opening of the control valve. Therefore, opening only requires a small magnetic force. Moreover, only one solenoid coil is needed to operate the control valve and the main valve. As a result, the installation space can be reduced.

[0009] In this case, the configuration of the magnetic armature of the main valve as a cylindrical armature is advantageous, since in this case the magnetic force decreases only slightly with increasing distance between the magnetic armature and the stationary stroke stop compared to flat armature designs, and this measure therefore serves to make it possible to design the magnetic circuit more compactly.

[0010] The particularly compact design of the proposed shut-off valve allows, besides the classical installation as a screw-in valve with an externally located solenoid coil, also an installation in which the solenoid coil of the shut-off valve is located in the narrow section of the bottle neck of a bottle-shaped pressure gas container. Such an arrangement is advantageous, since the narrow section has a particularly high degree of dimensional stability, so that the shut-off valve is optimally protected against external influences, for example in the event of an accident.

[0011] According to a preferred embodiment of the invention, the magnetic armature, which is configured as a flat armature, is radially spaced annularly from the housing, so that the magnetic flux lines of the magnetic circuit are guided exclusively through the axial working air gap, which results in the action of high forces on the control valve.

[0012] It is further proposed that the magnetic armature configured as a flat armature forms or has a control valve piston which cooperates with the control valve seat, i.e. the control valve piston and the magnetic armature are configured as one piece or are rigidly connected, so that the control valve piston and the magnetic armature move together.

[0013] The magnetic armature of the main valve, preferably configured as a cylindrical armature, is guided in the electromagnetic coil via a guide, and the control chamber is pneumatically throttled with the main valve chamber via the guide and / or a flow passage formed in the region of the guide. The guide is generated, for example, via a pole body or a sleeve integrated in the electromagnetic coil. The pneumatic connection between the control chamber and the main valve via the guide can be manufactured particularly simply and therefore inexpensively. At the same time, a throttle point can be configured in a simple manner via the guide. The pneumatic throttle connection ensures that less gas flows back into the control chamber at the open control valve than flows out via the open control valve in order to generate the pressure drop in the control chamber required for operating the main valve. Alternatively or additionally, as long as the pneumatic throttle connection is created via a flow passage formed in the region of the guide, the magnetic armature or the magnetic armature can have at least one flattened portion.

[0014] According to another preferred embodiment, a sealing element is arranged in the guide region. The pneumatic connection between the control chamber and the main valve chamber, which is necessary for a reliable closing of the main valve, is preferably effected via a throttle bore in the magnet armature. Instead of a throttle bore, at least one groove or a ground surface can also be provided in the magnet armature. Alternatively, at least one groove can also be formed in the coil body or in the housing forming the guide.

[0015] Furthermore, the magnetic armature configured as a cylindrical armature additionally has a cylindrical shape with a geometric shape and / or element for forming a stroke stop, which limits the maximum stroke of the magnetic armature, so that the stroke stop can be moved back and forth between two defined end positions. The geometric shape provided for this purpose can be configured, for example, as a local wall thickness in the peripheral area of ​​the magnetic armature. Alternatively or additionally, the magnetic armature can be connected to an additional element, for example having the shape of a ring or a sleeve. This element can be made of a material other than the magnetic armature, in particular a non-magnetic material, in order to act against the magnetic adhesion of the magnetic armature. In the form of a ring or sleeve, this element can be easily attached to the magnetic armature, in particular by crimping or screwing.

[0016] In order to ensure a pneumatic connection between the control chamber and the main valve chamber even during the entire stroke of the magnet armature, it is proposed that the stroke stop is designed to be non-tight. For this purpose, the geometry and / or elements for the construction of the stroke stop preferably have at least one flow passage in the abutment surface facing the electromagnetic coil for pneumatically connecting the control chamber and the main valve chamber. For example, at least one radially extending flow passage may be formed in this abutment surface. In order to avoid lateral forces acting on the magnet armature, a number of radially extending flow passages are preferably provided at the same angular distance from one another.

[0017] Furthermore, the magnetic armature of the main valve, which is configured as a cylindrical armature, is connected or can be connected to the main valve piston for opening and closing the main valve seat. In an ideal manner, the magnetic armature can be separated from the main valve piston, so that the magnetic armature and the main valve piston can move independently of each other. In this way, the throughflow restriction function can be realized by means of the main valve piston, since while the main valve piston is generally pressure compensated, the main valve piston only opens after the pressure has increased on the control end side. In order to ensure reliable opening, it is proposed as a further improved measure that the main valve piston is biased by the force of a spring in the direction towards the magnetic armature.

[0018] In a preferred embodiment, at least two springs arranged coaxially in the control chamber are received, with a first spring supported on the magnet armature of the control valve and a second spring supported on the magnet armature of the main valve. The reset of the two magnet armatures can thus be effected via separate springs. This allows the reset of the magnet armature of the control valve to be effected by a significantly smaller spring, so that a significantly smaller spring force has to be overcome to open the control valve. This means that only a smaller magnetic force is required, which has a favorable effect on the space required for mounting the electromagnetic coil.

[0019] More preferably, the control valve has a control end area which is connected to the control end area of ​​the main valve, and by opening the control valve, the pressure in the two control end areas is increased until the pressure ratio and thus the force ratio at the main valve opens the main valve.

[0020] Since the shut-off valve according to the invention is preferably used in a hydrogen tank system, it is further proposed to provide a hydrogen tank system having at least one pressurized gas container and a shut-off valve according to the invention for isolating the pressurized gas container, which hydrogen tank system can be used in particular in fuel cell vehicles or vehicles with a hydrogen combustion device. [Brief description of the drawings]

[0021] [Figure 1a] 2A-2C are schematic longitudinal sectional views of a first shut-off valve of the present invention in various switching positions; [Figure 1b] 2A-2C are schematic longitudinal sectional views of a first shut-off valve of the present invention in various switching positions; [Figure 1c] 2A-2C are schematic longitudinal sectional views of a first shut-off valve of the present invention in various switching positions; [Figure 1d] 2A-2C are schematic longitudinal sectional views of a first shut-off valve of the present invention in various switching positions; [Figure 1e] 2A-2C are schematic longitudinal sectional views of a first shut-off valve of the present invention in various switching positions; [Figure 1f] 2A-2C are schematic longitudinal sectional views of a first shut-off valve of the present invention in various switching positions; [Figure 2a] 3A-3D are schematic longitudinal sectional views of a second shut-off valve of the present invention in various switching positions. [Figure 2b] 3A-3D are schematic longitudinal sectional views of a second shut-off valve of the present invention in various switching positions. [Figure 2c] 3A-3D are schematic longitudinal sectional views of a second shut-off valve of the present invention in various switching positions. [Figure 2d] 3A-3D are schematic longitudinal sectional views of a second shut-off valve of the present invention in various switching positions. [Figure 2e] 3A-3D are schematic longitudinal sectional views of a second shut-off valve of the present invention in various switching positions. [Figure 2f]3A-3D are schematic longitudinal sectional views of a second shut-off valve of the present invention in various switching positions. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] The preferred embodiments and advantages of the present invention will be described in detail below with reference to the accompanying drawings.

[0023] The shut-off valve 1 shown in Figures 1a) to 1f) has a housing 2 in which an annular electromagnetic coil 3 is assembled for acting on a first magnet mover 4 and a second magnet mover 6. The two magnet movers 4, 6 are arranged coaxially with an axial gap between them, and move in opposite directions.

[0024] The first magnetic armature 4 is associated with the control valve 5 and is designed as a flat armature. The magnetic armature 4 simultaneously forms a control valve piston 14 which cooperates with a control valve seat 13. A through-hole 24 is formed in the magnetic armature 4, which ensures a pneumatic connection between the control valve chamber 9 and the rear control chamber 8 during the entire stroke of the magnetic armature 4. The magnetic armature 4 is biased by a spring 11 in the direction towards the control valve seat 13.

[0025] The second magnet mover 6 is arranged in correspondence with the main valve 7 and is configured as a cylindrical mover and is guided for stroke movement via a guide 15 formed in the electromagnetic coil 3. The geometric shape of a local thickening in the peripheral area of ​​the magnet mover 6 forms a stroke stopper 16 with a stop surface 17, in which a number of flow channels 18 are formed. The stroke stopper is thus configured non-airtight, so that a pneumatic connection between the rear control chamber 8 and the main valve chamber 10 is maintained via the guide 15 and the number of flow channels 18 during the entire stroke of the magnet mover 6.

[0026] The second magnetic armature 6 can be connected to a main valve piston 19 which cooperates with a main valve seat 20. The magnetic armature 6 and the main valve piston 19 can thus move independently of one another. In this way, a flow-limiting function is integrated into the main valve 7. To ensure that the main valve 7 opens, the main valve piston 19 is biased by a spring 21 in the direction towards the magnetic armature 6. The reset of the magnetic armature 6 and the main valve piston 19 is brought about by a spring 11 which is received in the control chamber 8.

[0027] The control valve 5 and the main valve 7 are connected via control end regions 22, 23 on the control end side.

[0028] 1a) shows the state in which the electromagnetic coil 3 is not energized and thus the shut-off valve 1 is closed. Gas flows via the high-pressure line 25 into the main valve chamber 10, so that a high pressure pHD prevails in this as well as in the control chamber 8 and in the control valve chamber 9. A low pressure pND prevails in the control end regions 22, 23.

[0029] When the electromagnetic coil 3 is energized, a magnetic field is generated, and the magnetic force of this magnetic field moves the magnet mover 4 of the control valve 5 in a direction toward the electromagnetic coil 3 (see FIG. 1b). Since the magnet mover 4 of the control valve 5 is radially spaced a from the housing 2, the magnetic flux lines of the magnetic circuit extend mainly through the axial working air gap, and therefore a strong magnetic force acts on the magnet mover 4, allowing the control valve 5 to be opened with little energy requirement or a relatively small electromagnetic coil 3.

[0030] When the control valve 5 is opened, gas flows out of the control valve chamber 9 into the control end region 22. At the same time, the pressure in the control chamber 8 drops, since gas flows backward from the control chamber 8 through the through-holes 24 in the magnet armature 4, because more gas flows out through the through-holes 24 and the control valve seat 13 than flows backward from the main valve chamber 10 through the guide 15. The pressure drop in the control chamber 8 is such that the force acting on the magnet armature 6 of the main valve 7, consisting of the magnetic force generated by the solenoid coil 3 and the air force acting to open, is sufficient to overcome the spring force of the spring 11, so that the magnet armature 6 moves away from the main valve piston 19 in the direction towards the solenoid coil 3 (see FIG. 1c). The main valve piston 19 still closes the main valve seat 20 for the time being, because a high pressure pHD still prevails in the main valve chamber 10 and a low pressure pND prevails in the control end region 23. If the main valve piston 19 is sufficiently pressure compensated, the spring 21 can only open the main valve 7 once the pressure in the control end region 23 has been increased (see FIG. 1d). In the open position of the main valve 7, pressure compensation is effected between the main valve chamber 10 and the control end region 23. At full pressure compensation, the main valve 7 and the control valve 5 are simply held open magnetically against the spring force of the spring 11.

[0031] To close the shut-off valve 1, the electromagnetic coil 3 is de-energized, so that the spring 11 returns the magnetic armature 4 of the control valve 5 or the control valve piston 14 to the control valve seat 13 (see FIG. 1e). When the control valve 5 is closed, the control chamber 8 is filled with gas from the main valve chamber 10 via the passage 18 and the guide 15, so that the pressure in the control chamber 8 rises again. The same applies to the pressure in the main valve chamber 10, because gas flows backward from the high-pressure line 25. This causes the air pressure acting on the magnetic armature 6 in the closing direction as well as the spring force of the spring 11 to return the magnetic armature 6 of the main valve 7 to its initial position. In this case, the magnetic armature 6 carries the main valve piston 19 with it, so that the main valve piston 19 is returned to the main valve seat 20 (see FIG. 1f).

[0032] An embodiment of the shut-off valve 1 of FIGS. 1a) to 1f) is explained below with the aid of FIGS. 2a) to 2f).

[0033] The shut-off valve 1 of FIGS. 2a) to 2f) has an additional spring 12, which, like the spring 11, is received in the control chamber 8 and serves to reset the magnet armature 4 of the control valve 5. The reset of the magnet armature 6 of the main valve 7 is furthermore brought about by the spring 11. Due to the provision of the additional spring 12, a comparatively small spring 12 can be selected, so that only a small force is required for the opening of the control valve 5. The opening is accordingly obtained by means of a small electromagnetic coil 3, so that further installation space is saved.

[0034] Otherwise, the functional mode of the shut-off valve 1 of FIGS. 2a) to 2f) corresponds to the functional mode of the shut-off valve 1 of FIGS. 1a) to 1f), so reference is made to the corresponding description. [Explanation of symbols]

[0035] 1 Shut-off valve 2. Housing 3. Electromagnetic Coil 4 First magnet mover 5. Control valve 6 Second magnet mover 7 Main Valve 8. Control Room 9 Control valve room 10 Main valve chamber 11. Spring 12 The Second Spring 13 Control valve seat 14 Control valve piston 15 Guide 16 Stroke stopper 17 Stopper surface 18 Flow Path 19 Main valve piston 20 Main valve seat 21 Spring 22,23 Control end area 24 Through hole 25 High Pressure Pipeline a Interval pHD High Pressure pND Low Pressure

Claims

1. A shut-off valve (1) for a hydrogen tank system, comprising: a control valve (5) actuated by a first magnet armature (4) and having a control valve piston (14) cooperating with a control valve seat (13); a main valve (7) actuated by a second magnet armature (6) and having a main valve piston (19) cooperating with a main valve seat (20); and a housing (2); The housing (2) accommodates an annular electromagnetic coil (3) for acting on the first magnetic mover (4) configured as a flat mover of the control valve (5) and the second magnetic mover (6) configured as a cylindrical mover of the main valve (7), the two magnetic movers (4, 6) being coaxially arranged and together defining a control chamber (8) formed in the electromagnetic coil (3), the control chamber (8) being connected to a control valve chamber (9) on the one hand and to a main valve chamber (10) on the other hand; The main valve chamber (10) is connected to a high-pressure piping line (25), and the control end region (22) of the control valve (5) is connected to the control end region (23) of the main valve (7), At least one spring (11, 12) is accommodated in the control chamber (8) to urge the first magnet mover (4) in a direction toward the control valve seat (13) and to urge the second magnet mover (6) in a direction toward the main valve seat (20). Shut-off valve for hydrogen tank system (1).

2. 2. The shut-off valve (1) according to claim 1, characterized in that the first magnetic armature (4) configured as a flat armature is annularly spaced apart from the housing (2) by a radial distance (a).

3. 3. The shut-off valve (1) according to claim 1 or 2, characterized in that the first magnetic armature (4) configured as a flat armature forms or has the control valve piston (14) cooperating with the control valve seat (13).

4. 3. The shut-off valve (1) according to claim 1 or 2, characterized in that the second magnetic armature (6), configured as a cylindrical armature, is guided within the electromagnetic coil (3) via a guide (15), and the control chamber (8) is connected in a throttling manner to the main valve chamber (10) via the guide (15) and / or a flow passage formed in the area of ​​the guide (15).

5. 3. The shut-off valve (1) according to claim 1 or 2, characterized in that the second magnetic armature (6) configured as a cylindrical armature has a cylindrical shape with geometric shapes and / or elements for additionally forming a stroke stop (16).

6. 6. The shut-off valve (1) according to claim 5, characterized in that the stroke stop (16) is designed to be non-tight and the geometric shapes and / or elements for forming the stroke stop (16) have at least one flow passage (18) on a stop surface (17) facing the electromagnetic coil (3) for connecting the control chamber (8) to the main valve chamber (10).

7. 3. The shut-off valve (1) according to claim 1 or 2, wherein the second magnetic armature (6) configured as a cylindrical armature is connected or connectable to the main valve piston (19) to open and close the main valve seat (20), and the main valve piston (19) is biased in a direction toward the second magnetic armature (6) by the spring force of a spring (21).

8. 3. The shut-off valve (1) according to claim 1 or 2, characterized in that at least two springs (11, 12) arranged coaxially in the control chamber (8) are accommodated, and these springs (11, 12) include a first spring (11) supported on the second magnetic armature (6) of the main valve (7) and a second spring (12) supported on the first magnetic armature (4) of the control valve (5).

9. 3. A hydrogen tank system comprising at least one pressurized gas container and a shut-off valve (1) according to claim 1 or 2 for isolating said pressurized gas container.

Images