Stop valve, method for operating stop valve, and electromagnetic assembly

Abstract

The invention relates to a shut-off valve (1) having an electromagnetic assembly (2) comprising an electromagnetic actuator (12) having an electromagnetic coil (6) and an armature (7) which is preloaded by a spring element (9) with a preloading force acting in the closing direction, the armature (7) for opening the shut-off valve (1) counteracting the preloading force of the spring element (9) by a magnetic flux, the armature (7) is movable in an opening direction along a movement axis (10) in order to release a fluid connection between the fluid inlet (4) and the fluid outlet (5), which fluid connection is cut off if there is no magnetic flux, by means of a magnetic force acting on the armature (7). In order to functionally optimize the shut-off valve (1), the electromagnetic assembly (2) is structurally implemented in such a way that a targeted asymmetric magnetic force distribution with respect to the movement axis (10) of the armature (7) is obtained.

Description

Technical Field

[0001] The invention relates to a stop valve with an electromagnetic assembly, the electromagnetic assembly comprising an electromagnetic actuator with an electromagnetic coil and an armature, the armature being preloaded by a spring element with a preload force acting in the closing direction, wherein, in order to open the stop valve, the armature can be moved along a movement axis in the opening direction by a magnetic flux against the preload force of the spring element, so that a fluid connection between a fluid inlet and a fluid outlet, which is blocked in the absence of a magnetic flux, is released by a magnetic force pulling the armature. The invention also relates to a method for operating a stop valve of this type and an electromagnetic assembly for such a stop valve, in particular individual components of the electromagnetic assembly. The stop valve is preferably a safety electromagnetic valve, also known as a shut-off valve (shut-off-ventil). Background Art

[0002] German laid-open patent application DE 10 2020 201 172 A1 discloses a device for storing compressed gas, for example hydrogen or an inert gas, comprising a storage line to which at least one compressed gas container is attached, wherein a safety solenoid valve, also referred to as a shut-off valve, is integrated in the storage line. Summary of the invention

[0003] The object of the present invention is to improve the functionality of a shut-off valve according to the preamble of claim 1 .

[0004] A stop valve has an electromagnetic assembly, which includes an electromagnetic actuator with an electromagnetic coil and an armature, which is preloaded by a spring element with a preload force acting in the closing direction, wherein, in order to open the stop valve, the armature is moved by a magnetic flux along a movement axis in the opening direction against the preload force of the spring element, so that a fluid connection between a fluid inlet and a fluid outlet, which is blocked in the absence of a magnetic flux, is released by a magnetic force pulling the armature, in the case of the stop valve, the object is achieved in the following way: the electromagnetic assembly is designed in such a way that a magnetic force distribution is obtained that is asymmetrical in a targeted manner with respect to the movement axis of the armature. The asymmetrical magnetic force distribution makes it possible to achieve a large pressure difference and a large flow through the opened fluid connection with only one sealing seat and only one electromagnetic actuator. The magnetic force exerted on the armature for opening the stop valve is a tensile force. The asymmetrical magnetic force distribution is particularly advantageous in causing a deflection of the armature during opening. Therefore, the electromagnetic actuator of the claimed stop valve is also referred to as a pivot-pull actuator.

[0005] A preferred embodiment of the shut-off valve is characterized in that the armature movable along its axis of motion is additionally deflectable relative to its axis of motion by an asymmetric magnetic force distribution. The deflection of the armature can be achieved, for example, by a correspondingly large guide gap between the armature and the guide geometry. The magnetic force for opening the shut-off valve advantageously does not act on the armature centrally along the axis of motion. The magnetic force advantageously acts laterally offset relative to the axis of motion. Thus, when the shut-off valve is opened, a torque is applied to the armature via the asymmetric magnetic force distribution. When the shut-off valve is opened, this torque causes the armature to produce the desired deflection. The asymmetric magnetic force distribution can be implemented in different parts of the electromagnetic assembly.

[0006] Another preferred embodiment of the stop valve is characterized in that the armature guided along its axis of motion in the guide geometry has a convex armature boundary surface, which faces the guide geometry and enables the desired deflection movement of the armature when the armature is loaded with asymmetrically acting magnetic forces. The guide geometry for the armature has, for example, the shape of a straight cylindrical circumferential side surface. The armature obtains a spherical profile due to the convex armature boundary surface, while if there is no convex armature boundary surface, the armature would basically have a disk-shaped or cylindrical configuration. The armature is embodied preferably rotationally symmetrically about its axis of motion (also referred to as the armature axis). The armature is, for example, bounded by a circular surface at its end.

[0007] Another preferred embodiment of the shut-off valve is characterized in that the armature has an asymmetrical design with respect to its axis of movement. The asymmetrical design of the armature makes it possible that the magnetic force does not act centrally on the armature axis, but rather is laterally offset and thus generates a torque acting on the armature. This makes it possible in a simple manner to achieve the desired deflection movement of the armature when the shut-off valve is opened.

[0008] Another preferred embodiment of the shut-off valve is characterized in that the armature has at least one material gap to achieve an asymmetric magnetic force distribution when the shut-off valve is opened. The material gap can be implemented as a step or flattened portion (Abflachung) at the end of the armature. The material gap can also include at least one groove on the side of the armature. The groove can be implemented as a circle or rectangle. The size and configuration of the material gap and, if necessary, the number of multiple material gaps are designed according to the asymmetry of the magnetic force when the shut-off valve is opened.

[0009] Another preferred embodiment of the shut-off valve is characterized in that the material recess is arranged on the end face of the armature facing the counterpole of the electromagnetic component. The desired asymmetry of the magnetic force can thus be easily achieved in terms of production technology.

[0010] Another preferred embodiment of the shut-off valve is characterized in that the shut-off valve has a centered outlet channel and a non-centered inlet channel. The terms "non-centered" and "centered" relate to the axis of motion of the armature. Centering means, in particular, that the outlet channel is arranged coaxially with respect to the axis of motion. Non-centered, on the other hand, means that the inlet channel extends parallel or obliquely with respect to the axis of motion of the armature. The claimed arrangement of the outlet channel and the inlet channel has proven to be advantageous with regard to the desired deflection movement of the armature when the shut-off valve is opened. It is particularly advantageous here that the flow forces assist or reinforce the deflection movement of the armature caused by the asymmetrical magnetic force distribution through the fluid connection released when the armature is deflected.

[0011] Another preferred embodiment of the stop valve is characterized in that the stop valve is designed as a seat valve with a closed position in which the armature is arranged symmetrically with respect to its axis of movement. When the stop valve is closed, the armature or a closing element coupled to the armature is brought symmetrically into the closed position and held in the closed position by the preload of the spring element and by the pressure difference acting on the armature or on the closing element coupled to the armature. In this way, an undesired opening of the stop valve is safely avoided during operation.

[0012] In a method for operating a shut-off valve described above, preferably a shut-off valve in a fuel cell system, the above-mentioned object is achieved alternatively or additionally in that when the shut-off valve is opened, the armature is deflected by an asymmetrical magnetic force distribution in order to achieve a greater fluid flow. The greater fluid flow is advantageously achieved by only one sealing seat and by only one electromagnetic actuator.

[0013] If necessary, the present invention also relates to a fuel cell system having the above-mentioned shut-off valve. The shut-off valve is advantageously arranged in the anode path of the fuel cell system.

[0014] If necessary, the present invention also relates to an electromagnetic assembly for the above-mentioned shut-off valve, in particular to a single component of the electromagnetic assembly, preferably an armature. The mentioned components can be sold separately.

[0015] Further advantages, features and details of the invention will be described in the following description, in which different exemplary embodiments are described in detail with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] It shows:

[0017] Figure 1 is a longitudinal schematic diagram of a stop valve having an electromagnetic assembly including a deflectable armature;

[0018] Figure 2 , Figure 3 , Figure 4 Is from Figure 1 Three embodiments of the armature are shown in the form of a front view and a top view respectively;

[0019] Figure 5 Is from Figure 1 Schematic diagram of an electromagnetic assembly with different arrows to illustrate the function of the stop valve in which the armature is deflected when opening;

[0020] Figure 6 is a schematic diagram of a traditional fuel cell system. DETAILED DESCRIPTION

[0021] Figure 6 A schematic diagram of a conventional fuel cell system 101 is shown. The fuel cell system 101 includes an anode path 104 that connects a hydrogen tank 128 and an anode 112 of a fuel cell stack 120. Within the anode path 104, at least two valves 132, 134 are arranged.

[0022] The first valve 132 is configured as a shut-off valve or cut-off valve 132. The cut-off valve 132 is open during operation of the fuel cell system 101. When the fuel cell system 101 is shut down, the cut-off valve 132 is closed so that hydrogen can no longer flow from the hydrogen tank 128 to the anode 112.

[0023] The second valve 134 is designed as an HGI (hydrogen gas injector) valve 134 and can supply a required amount of hydrogen to the anode 112 depending on the respective operating state of the fuel cell stack 120 .

[0024] The connecting line 108 is arranged between the first valve 132 and the second valve 134. A sensor 110 is located in the connecting line 108, which can determine the pressure within the connecting line 108.

[0025] In the hydrogen tank 128, hydrogen is usually stored under high pressure. To reduce the pressure, a pressure regulating valve 130 may be located between the hydrogen tank 128 and the first valve 132, which reduces the pressure before the hydrogen flows to the HGI valve 134 or the anode 112. The pressure at the inlet of the first valve 132 corresponding to the tank pressure or having been reduced by the pressure regulating valve 130 is referred to as the supply pressure.

[0026] The fuel cell system 101 further comprises a cathode gas supply line 115 , which supplies air to cathodes 116 of the fuel cell stack 120 , and a cathode gas discharge line 117 , which discharges used air and exhaust gas from the fuel cell stack 120 .

[0027] When the fuel cell system 101 is in operation, hydrogen is output to the anode 112 along the anode path 104 via the hydrogen tank 128, the first valve 132, and via the second valve 134. Since the anode 112 is supplied with an over-metered amount of hydrogen for performance and component protection reasons, unconsumed hydrogen flows back via the anode gas return line 114 and is introduced into the anode path 104 again at the hydrogen return location 122.

[0028] A recirculation pump 142 , as well as other valves and components, may be disposed within the anode gas return line 114 .

[0029] Since nitrogen diffuses from cathode 116 to anode 112 during the fuel cell reaction and accumulates in increasing proportions within anode path 104 via anode gas return line 114 , the nitrogen accumulated within anode path 104 must be removed from time to time from fuel cell system 101 .

[0030] This can be done by means of a vent valve 141 arranged in the anode gas return line 114. In order to remove excess water from the anode 112 or the anode path 104, a water separator, a water tank and a drain valve can also be arranged in the anode gas return line 114, which are not described in detail in the drawings because they are not important for the present invention.

[0031] The fuel cell system 101 has a measuring assembly for checking at least one valve 132, 134. The measuring assembly comprises a sensor 110 for detecting a measured value for determining the current pressure at a location within the connecting line 108 of the anode path 104. In an alternative embodiment, the sensor 110 can additionally also detect the current temperature of the gas at this location.

[0032] The control unit 111 and the sensor 110 are connected by wire or wirelessly to detect and analyze and evaluate measured values, especially pressure values ​​and / or temperature values ​​according to the method of the present invention to check whether there is a leakage in the first valve (shut-off valve) 132 or the second valve (HGI valve).

[0033] The control unit 111 is also connected to other components of the fuel cell system 101. The control unit 111 may also have a connection with the first valve 132 and / or the second valve 134 to detect the opening and closing time of the first valve 132 and the second valve 134 and include it in the calculation of the leakage rate.

[0034] exist Figure 1 The stop valve 1 is schematically shown in a longitudinal section. The stop valve 1 can also be referred to as a cut-off valve. The stop valve 1 is, for example, Figure 6 A shut-off valve such as the one marked with 132 in FIG.

[0035] In hydrogen systems, particularly in fuel cell systems, stop valves 1 are used to control and safely shut down tank systems when they are stopped, for example in emergency situations. Here, depending on the operating state, high pressure differences and large flows may occur, which must be quickly interrupted by stop valves 1.

[0036] exist Figures 1 to 5 It is shown how, given a given installation space and / or at maximum available supply energy, rapid and stable closing can be ensured even at maximum pressure differences and maximum flow rates in the open state of the shut-off valve 1 .

[0037] Advantageously, the shut-off valve 1 comprises only one sealing seat 11 and only one electromagnetic actuator 12. By means of the one sealing seat 11 and the one electromagnetic actuator 12, large pressure differences and large flow rates during operation of the shut-off valve 1 when open can also be advantageously achieved.

[0038] The stop valve 1 comprises an electromagnetic assembly 2 having a pole tube 3, an electromagnetic coil 6, an armature 7 and a counterpole 8. The armature 7 can be moved back and forth in a translational manner along a movement axis 10, i.e. Figure 1 The armature 7 is preloaded away from the counterpole 8 by the spring element 9, i.e. Figure 1 Middle downward.

[0039] In the pole tube 3 Figure 1 At the lower end of the figure, the fluid inlet 4 and the fluid outlet 5 are schematically shown. The fluid outlet 5 comprises, for example, a centered outlet channel 17. The centered outlet channel 17 is coaxially arranged relative to the movement axis 10 of the armature 7, which is also referred to as the armature axis 10. The fluid inlet 4 comprises a non-centered inlet channel 16. The inlet channel 16 extends obliquely relative to the armature axis 10.

[0040] exist Figure 1 The sealing seat 11 is indicated by two circles in the figure. The sealing seat 11 is closed by the armature 7. Of course, the armature 7 can also be combined with an actuator and / or a closing body. The key point in the schematic diagram is that the sealing seat 11 is kept in its position by the spring preload of the spring element 9. Figure 1 In the closed state shown in FIG, the spring preload forces the armature 7 to Figure 1 Loading down.

[0041] When the electromagnetic coil 6 of the electromagnetic actuator 12 is energized, the armature 7 is Figure 1 The armature 7 is pulled / attracted upwards in the stop valve 1, wherein the fluid passage between the fluid inlet 4 and the fluid outlet 5 is released at the sealing seat 11. When the stop valve 1 is open, the armature 7 is pulled / attracted upwards by the electromagnetic assembly 2. Figure 1 There is no magnetic flux or magnetic circuit shown in Figure 1 Therefore, the electromagnetic actuator 12 is also called a pull-type electromagnetic actuator 12.

[0042] However, according to a basic aspect of the invention, the armature is not only arranged in the axial direction (i.e. in the pole tube 3) but also in the Figure 1 The armature 7 comprises a convex armature boundary surface 14, which enables the armature 7 to be deflected in the guide geometry 13 of the pole tube 3. The guide geometry 13 has the configuration of a straight cylindrical circumferential side surface.

[0043] The armature 7 has essentially a straight cylindrical shape, wherein the armature 7 is given a barrel-shaped shape by the convex armature boundary surface 14. The armature 7 can be rotated radially at least to a certain extent about its center point by the convex armature boundary surface 14. This radial rotation, which is also called deflection, is Figure 5 is shown in .

[0044] exist Figures 2 to 4 , it is shown how the asymmetric design of the armature 7 enables the following: the magnetic force generated by the electromagnetic assembly 2 does not act centrally on the armature axis 10 when the shut-off valve 1 is opened, but is offset laterally and thus generates a torque acting on the armature 7. The asymmetry of the magnetic force does not necessarily have to be realized in the armature 7, but can also be taken into account in other parts of the electromagnetic assembly 2, for example in the counterpole 8 or in the excitation system of the electromagnetic assembly 2 with the electromagnetic coil 6.

[0045] Figures 2 to 4 It is shown how the asymmetry of the magnetic force can be achieved by means of a targeted change in the geometry of the armature 7. The armature 7 is provided with a material gap 15 to achieve the asymmetry of the magnetic force. The material gap 15 can be designed in different ways. It is important that the material gap 15 gives the armature 7 an asymmetric shape with respect to the armature axis 10.

[0046] exist Figure 2 In the embodiment, the material recess 15 is implemented as a flattened portion. Figure 3 In the embodiment, the material recess 15 is implemented as a rectangular groove. Figure 4 In the embodiment shown, the material recess 15 is embodied as a circular groove.

[0047] exist Figure 5 The working principle of the stop valve 1 is explained in FIG. The force distribution in the closed state of the stop valve is shown under the rectangular symbol 21. The force distribution when the stop valve is open is shown under the arrow symbol 22. The force distribution in the open state of the stop valve is shown under the rectangular symbol 23. The force distribution when the stop valve is closed is shown under the arrow symbol 24.

[0048] The arrow 31 depicts Figure 19. The pressure difference force is shown by arrow 32, which is generated due to the different pressures at the fluid inlet 4 and the fluid outlet 5 and acts on the armature 7. The left and right supporting forces are shown by arrows 33 and 34. The magnetic force generated by the electromagnetic assembly 2 and acting on the armature 7 for opening the stop valve is shown by arrows 41 and 42.

[0049] The stop valve Figure 5 The basic idea of ​​the working principle shown in is borrowed from the opening of a sealed glass jar. Figure 5 In a simplified diagram of , the forces are divided into a left half and a right half. In reality, it is a toroidal surface and therefore of course an annular force.

[0050] When the stop valve is closed, the spring element (also referred to as spring for short) presses the armature 7 symmetrically into its sealing seat (also referred to as seat for short) by means of its spring force 31 and the pressure difference force 32. Due to the symmetry in the closed state, the left support force 33 and the right support force 34 are equal in magnitude and a central point of action of the pressure difference force 32 is obtained.

[0051] When the electromagnetic coil (referred to as the coil for short) is energized, a magnetic flux is generated through the armature 7. The magnetic flux causes magnetic forces 41, 42 to be generated in the opposite poles of the electromagnetic assembly via the working air gap. Due to the asymmetry of the armature 7, the magnetic forces 41, 42 do not act centrally on the armature 7, but have a torque, for example Figure 5 This is indicated below the middle arrow symbol 22 by arrows 41 and 42 of different lengths.

[0052] The torque produces a deflection of the armature 7, thereby reducing the seat Figure 5 The load on the right side of the Figure 5 As shown in the figure, arrows 33 and 34 of different lengths are shown below the arrow symbol 22. Here, Figure 5 The force application point of the pressure difference force 32 in the seal is offset to the left, toward the deflection point or deflection axis on the seal seat. Figure 5 The deflection point is marked with 40.

[0053] If the armature 7 is strongly deflected so that the seat is not sealed on one side, gas flows from the gas tank via the fluid inlet and the fluid outlet into the downstream system, for example Figure 5 This is shown in the middle below the arrow symbol 22 by the dashed arrow 36. This in turn leads to a reduction in the pressure difference and thus a reduction in the pressure difference force, as shown in Figure 5 As shown by arrow 37 and arrow 32.

[0054] If the sum of the pressure difference force 32 and the spring force 31 is less than or equal to the axial total magnetic force 41, 42, the armature 7 moves in the direction of the counterpole 8. When the armature 7 hits the counterpole 8, a deflection point is also obtained on the counterpole 8, which is formed by the Figure 5 The arrow 38 on the right below the arrow symbol 22 indicates this.

[0055] Since this deflection point is ideally located outside the magnetic force action points of the magnetic forces 41, 42, the magnetic forces 41, 42 rotate the armature 7 back along its armature axis 10 in the opposite direction of the previous rotational movement. Figure 5 The spring shown below the arrow symbol 24 in the figure acts on the armature 7 in the center. When there is no magnetic force, when the electromagnetic assembly is cut off, the armature 7 is in Figure 5 Move downward in the middle and close the sealing seat.

Claims

1. A stop valve (1) having an electromagnetic assembly (2), the electromagnetic assembly comprising an electromagnetic actuator (12) having an electromagnetic coil (6) and an armature (7), the armature being preloaded by a spring element (9) with a preload force acting in a closing direction, wherein: In order to open the shut-off valve (1), the armature (7) can be moved in an opening direction along a movement axis (10) by means of a magnetic flux against the preload force of the spring element (9), so as to release a fluid connection between a fluid inlet (4) and a fluid outlet (5) which would be blocked in the absence of a magnetic flux by means of a magnetic force pulling the armature (7), characterized in that the electromagnetic component (2) is structurally implemented so as to obtain a magnetic force distribution which is specifically asymmetrical with respect to the movement axis (10) of the armature (7).

2. The stop valve according to claim 1, characterized in that: The armature (7) which is movable along its axis of movement (10) can additionally be deflected relative to its axis of movement (10) by the asymmetrical magnetic force distribution.

3. The stop valve according to claim 2, characterized in that: An armature (7) guided along an axis of movement (10) of the armature in a guide geometry (13) has a convex armature boundary surface (14) which faces the guide geometry (13) and enables a desired deflection movement of the armature (7) when the armature (7) is loaded with an asymmetrically acting magnetic force.

4. A shut-off valve according to any one of the preceding claims, characterized in that The armature (7) has an asymmetrical configuration with respect to its axis of movement (10).

5. The stop valve according to claim 3, characterized in that: The armature (7) has at least one material recess (15) in order to achieve the asymmetrical magnetic force distribution when the solenoid valve (1) is opened.

6. The stop valve according to claim 5, characterized in that: The material recess (15) is arranged on the end face of the armature (7) facing the counterpole (8) of the electromagnetic component (2).

7. A shut-off valve according to any one of the preceding claims, characterized in that The shut-off valve (1) has a central outlet channel (17) and a non-central inlet channel (16).

8. A shut-off valve according to any one of the preceding claims, characterised in that The shut-off valve (1) is designed as a seat valve which has a closed position in which the armature (7) is arranged symmetrically with respect to its axis of movement (10).

9. A method for operating a shut-off valve (1) according to any one of the preceding claims, characterized in that When the shut-off valve (1) is opened, the armature (7) is deflected by the asymmetrical magnetic force distribution to achieve a larger fluid flow rate.

10. A solenoid assembly (2) for a shut-off valve (1) according to any of the preceding claims, in particular an individual component of the solenoid assembly (2), preferably an armature (7).

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