Dosing valve

Abstract

Dosing valve (1) for supplying gas to a fuel cell, comprising a base body (10) in which an electromagnet (12) is arranged; and a nozzle (14) connected to the base body (10), wherein a first armature (16) for actuating a first closure element (18) is arranged in the nozzle (14), wherein the first closure element (18) is designed to open and close a first sealing seat (20) of the metering valve (1), wherein a second armature (24) guided from the base body (10) through a bore (22) formed in the nozzle (14) into the nozzle (14) is arranged in the nozzle (14) for actuating a second closure element (26), wherein the second closure element (26) is designed to open and close a second sealing seat (28) of the metering valve (1), wherein the first armature (16) and the second armature (24) can be actuated by the electromagnet (12),wherein the nozzle (14) has an inlet opening (31) for supplying gas to the metering valve (1) and an outlet opening (32) for discharging gas to the fuel cell, characterized in that the first sealing seat (20) and the second sealing seat (28) can be independently flowed against and opened by a gas flow entering through the inlet opening (31).

Description

[0001] The invention relates to a metering valve for supplying gas to a fuel cell. State of the art

[0002] Fuel cell systems conventionally comprise a fuel cell having a cathode compartment and an anode compartment separated from the cathode compartment by a membrane, further comprising an anode gas source, a gas supply connected to the anode gas source and the anode compartment, an exhaust air line connected to the anode compartment, a cathode gas source, a gas supply connected to the cathode gas source and the cathode compartment, and an exhaust air line connected to the cathode compartment.

[0003] A dosing valve is conventionally arranged in the gas supply of the anode chamber.

[0004] DE 10 2013 226 820 A1 discloses a control unit which detects an operating state of the fuel cell and controls the metering valve depending on the operating status, i.e. in particular varies a flow cross-section or a pressure.

[0005] DE 10 2005 033 134 A1 discloses a metering valve suitable for supplying gas to a fuel cell, comprising a base body in which an electromagnet is arranged.

[0006] A key requirement for the further development of the metering valve is to increase the pressure upstream of the metering valve, meaning the required closing spring force must be increased accordingly. As the spring force increases, the load on the sealing seat increases, leading to increased wear on the already critical seal. Furthermore, optimizing the metering valve's tightness while simultaneously optimizing the valve's opening force is desirable. Disclosure of the invention

[0007] The present invention provides a metering valve for supplying gas to a fuel cell, comprising a base body in which an electromagnet is arranged, and a nozzle connected to the base body. A first armature for actuating a first closure element is arranged in the nozzle. The first closure element is designed to open and close a first sealing seat of the metering valve. A second armature is arranged in the nozzle and is guided from the base body through a bore formed in the nozzle into the nozzle and is designed to actuate a second closure element. The second closure element is designed to open and close a second sealing seat of the metering valve. The first armature and the second armature are actuable by the electromagnet. The nozzle has an inlet opening for supplying gas to the metering valve and an outlet opening for discharging gas to the fuel cell.and wherein the first sealing seat and the second sealing seat can be independently flowed against and opened by a gas stream entering through the inlet opening.,

[0008] One idea of ​​the present invention is that, due to the sequential flow to the first sealing seat and the second sealing seat, with the first sealing seat being the first to be flowed to, the sealing force of the respective spring elements applying a spring force to the first armature and the second armature can be supported by a pressure force of the gas flow entering through the inlet opening. At higher pressures, the pressure force generated by the gas flow advantageously increases. This creates a self-regulating system.

[0009] Advantageous embodiments and further developments emerge from the subclaims and from the description with reference to the figures.

[0010] According to a preferred development, the first sealing seat can be subjected to flow through the inlet opening formed in the radial direction of the housing of the metering valve, wherein the first sealing seat and the second sealing seat are fluidically connected to one another. Thus, opening the first sealing seat can assist opening the second sealing seat.

[0011] According to a further preferred development, the outlet opening of the nozzle for discharging gas to the fuel cell is formed in the region of the second sealing seat, wherein the second sealing seat fluidically communicates with the first closure element of the first sealing seat via a first bore, and wherein the second sealing seat has a second bore fluidically communicating with the second closure element of the second sealing seat. Thus, the gas mass flow from the first sealing seat to the second sealing seat can flow both via the cavity of the nozzle and via the first bore fluidically communicating with the second sealing seat.

[0012] According to a further preferred development, a first air gap is formed between the first armature and a first housing element of the metering valve, and a second air gap is formed between the second armature and a magnetic core of the metering valve, wherein the first air gap has a smaller dimension than the second air gap. Thus, the first armature advantageously has a high magnetic force, which can be generated with a low drive current.

[0013] According to a further preferred development, when a control current is applied to a magnetic coil of the electromagnet, which is less than or equal to a predetermined threshold value, the first armature is designed to open the first sealing seat at least partially, and the second armature is designed to remain in a closed position. Thus, by opening the first sealing seat at least partially, pressure relief can be generated, and the second sealing seat can be opened with less force. Furthermore, rapid opening and closing of the first sealing seat is possible, which allows, for example, small volumes of gas to be conveyed.According to a further preferred development, the first sealing seat and the second sealing seat can be opened independently. Upon application of a control current to the solenoid coil of the electromagnet that is greater than the predetermined threshold value, the first armature is configured to remain in the open state and the second armature is configured to open the second sealing seat at least partially. Thus, the first sealing seat advantageously has the function of relieving pressure from the second sealing seat, and the second sealing seat has the function of regulating a mass flow of the gas.

[0014] According to a further preferred development, the first armature is resettable by a first spring element and the second armature by a second spring element, wherein the first spring element has a greater spring force than the second spring element. Due to the high magnetic force at low drive current of the first armature, a stronger spring element is required to reset the armature compared to the second armature, which requires a larger drive current.

[0015] According to a further preferred development, the first closure element is formed by the first anchor or integrally with the first anchor, wherein a contact surface of the first closure element on the first sealing seat has a sealing element, which is preferably made of an elastomer material. Thus, a good seal of the sealing seat can be advantageously achieved.

[0016] According to a further preferred development, a residual air gap disk is arranged between the first armature and the first housing element of the metering valve to prevent the first armature from magnetically adhering to the first housing element. This advantageously ensures that the first armature is always arranged at a distance from the first housing element.

[0017] According to a further preferred development, a sleeve, preferably made of a non-magnetic material, is arranged between the second armature and the first housing element of the metering valve housing. The sleeve is designed to magnetically separate the magnetic core from the first housing element of the housing. By providing the sleeve, a magnetic separation of the magnetic core from the first housing element can thus be advantageously achieved.

[0018] According to a further preferred development, the sleeve is designed to hold a second housing element of the metering valve housing, which is arranged adjacent to the first housing element of the housing, and wherein the first armature has an opening through which a projection of the second housing element of the housing extends. Thus, the second housing element of the housing can be advantageously held by the sleeve.

[0019] According to a further preferred development, the first armature is arranged between an inner surface of a second housing element of the housing, arranged adjacent to the first housing element of the housing, and a projection of the second housing element of the housing, and is guideable on the inner surface of the second housing element or on the projection of the second housing element. Thus, the first armature can advantageously be guided selectively on different surfaces.

[0020] The described designs and further training courses can be combined as desired.

[0021] Further possible embodiments, further developments and implementations of the invention also include combinations of features of the invention described previously or below with regard to the exemplary embodiments that are not explicitly mentioned. Short description of the drawings

[0022] The accompanying drawings are intended to provide a further understanding of embodiments of the invention. They illustrate embodiments and, in conjunction with the description, serve to explain principles and concepts of the invention.

[0023] Other embodiments and many of the aforementioned advantages will become apparent upon review of the drawings. The elements illustrated in the drawings are not necessarily drawn to scale.

[0024] They show: Fig. 1 is a cross-sectional view of a metering valve for supplying gas to a fuel cell according to a preferred embodiment of the invention; Fig. 2 a sectional view AA of the Fig. 1 according to the preferred embodiment of the invention; and Fig. 3 a detailed view of a first sealing seat of the metering valve for supplying gas to a fuel cell according to another preferred embodiment of the invention.

[0025] In the figures of the drawings, the same reference symbols designate the same or functionally equivalent elements, parts or components, unless otherwise stated.

[0026] Fig. 1 shows a cross-sectional view of a metering valve for supplying gas to a fuel cell according to a preferred embodiment of the invention.

[0027] The metering valve 1 for supplying gas to a fuel cell has a base body 10. An electromagnet 12 is arranged in the base body 10. The metering valve 1 further has a nozzle 14. The nozzle 14 is connected to the base body 10. A first armature 16 for actuating a first closure element 18 is arranged in the nozzle 14. The first closure element 18 is designed to open and close a first sealing seat 20 of the metering valve 1.

[0028] Furthermore, a second armature 24 is arranged in the nozzle 14, which is guided from the base body 10 through a bore 22 formed in the nozzle 14 into the nozzle 14 and is used to actuate a second closure element 26. The second closure element 26 is designed to open and close a second sealing seat 28 of the metering valve 1.

[0029] The first armature 16 and the second armature 24 are actuated by the electromagnet 12. The nozzle 14 has an inlet opening 31 for supplying gas to the metering valve 1 and an outlet opening 32 for discharging gas to the fuel cell. The first sealing seat 20 and the second sealing seat 28 can be independently exposed to and opened by a gas flow entering through the inlet opening 31.

[0030] The first sealing seat 20 can be flowed through the inlet opening 31 formed in the radial direction R of a housing 35 of the metering valve 1. The first sealing seat 20 and the second sealing seat 28 are fluidically connected to one another.

[0031] The outlet opening 32 of the nozzle 14 is designed to discharge gas to the fuel cell in the region of the second sealing seat 28. The second sealing seat 28 fluidically communicates with the first closure element 18 of the first sealing seat 20 via a first bore 34. The second sealing seat 28 has a second bore 37 fluidically communicating with the second closure element 26 of the second sealing seat 28.

[0032] A first air gap 38 is formed between the first armature 16 and the first housing element 36 of the housing of the metering valve 1, and a second air gap 42 is formed between the second armature 24 and a magnetic core 40 of the metering valve 1. The first air gap 38 has a smaller dimension than the second air gap 42.

[0033] When a control current is applied to a magnetic coil 44 of the electromagnet 12, which is less than or equal to a predetermined threshold value, the first armature 16 is designed to open the first sealing seat 20 at least in sections, and the second armature 24 is designed to remain in a closed position.

[0034] The first sealing seat 20 and the second sealing seat 28 can be opened independently. When a control current greater than the predetermined threshold is applied to the solenoid coil 44 of the electromagnet 12, the first armature 16 is configured to remain in the open state, and the second armature 24 is configured to open the first sealing seat 20 at least partially.

[0035] The first armature 16 is formed by a plate armature, and the second armature 24 is formed by a plunger armature. The first armature 16 is resettable by a first spring element 48. The second armature 24 is resettable by a second spring element 50. The first spring element 48 has a greater spring force than the second spring element 50.

[0036] The first closure element 18 is formed by the first armature 16 or integrally with the first armature 16. A contact surface 52 of the first closure element 18 has a sealing element 54 at the first sealing seat 20. The sealing element 54 is preferably formed from an elastomer material.

[0037] A residual air gap disc 56 is arranged between the first armature 16 and the first housing element 36 of the housing 35 of the metering valve 1 to prevent magnetic adhesion of the first armature 16 to the first housing element 36 of the housing 35.

[0038] A sleeve 58 made of a non-magnetic material is arranged between the second armature 24 and the first housing element 36 of the housing 35 of the metering valve 1. The sleeve 58 is designed to magnetically separate the magnetic core 40 from the first housing element 36 of the housing 35.

[0039] The sleeve 58 is designed to hold a second housing element 60 of the housing 35 of the metering valve 1, which is arranged adjacent to the first housing element 36 of the housing 35. The first armature 16 has an opening 62 through which a projection 64 of the second housing element 60 of the housing 35 extends.

[0040] Fig. 2 shows a sectional view AA of the Fig. 1 according to the preferred embodiment of the invention. The first armature 16 has an opening 62. A projection 64 of the second housing element 60 extends through the opening 62. The first armature 16 can thus advantageously be guided along the projection 64 of the second housing element 60.

[0041] Fig. Figure 3 shows a detailed view of a first sealing seat of the metering valve for supplying gas to a fuel cell according to another preferred embodiment of the invention. In the present embodiment, the first armature 16 does not have an opening for receiving the projection of the second housing element of the housing. Instead, the first armature 16 or side walls of the first armature 16 can be guided between wall surfaces of the second housing element 60 in the axial direction of the metering valve 1.

[0042] The first armature 16 is arranged between an inner surface of a second housing element 60 of the housing 35 arranged adjacent to the first housing element 36 of the housing 35 and a projection 64 of the second housing element 60 of the housing 35.

[0043] The first armature 16 can be guided along the inner surface of the second housing element 60. Alternatively, the first armature 16 can be guided along the projection 64 of the second housing element 60.

[0044] The information relating to Fig. The opening of the first armature 16 described in Figure 2 can thus advantageously be omitted. The first spring element 48, which applies a spring force to the first armature 16 to reset the first armature 16, is advantageously supported on the first housing element 36 of the housing 35.

[0045] Although the present invention has been described above using preferred embodiments, it is not limited thereto, but can be modified in a variety of ways. In particular, the invention can be changed or modified in a variety of ways without deviating from the essence of the invention.

[0046] For example, the shape, dimensions and / or properties of the components of the dosing valve can be modified according to the respective structural or design requirements.

Claims

[1] Dosing valve (1) for supplying gas to a fuel cell, comprising a base body (10) in which an electromagnet (12) is arranged;and a nozzle (14) which is connected to the base body (10), wherein a first armature (16) for actuating a first closure element (18) is arranged in the nozzle (14), wherein the first closure element (18) is designed to open and close a first sealing seat (20) of the metering valve (1), wherein a second armature (24) is arranged in the nozzle (14) and is guided from the base body (10) through a bore (22) formed in the nozzle (14) into the nozzle (14) for actuating a second closure element (26), wherein the second closure element (26) is designed to open and close a second sealing seat (28) of the metering valve (1), wherein the first armature (16) and the second armature (24) are actuable by the electromagnet (12), wherein the nozzle (14) has an inlet opening (31) for supplying gas to the metering valve (1) and an outlet opening (32) for discharging gas to the fuel cell; characterized bythat the first sealing seat (20) and the second sealing seat (28) can be independently flowed against and opened by a gas stream entering through the inlet opening (31). [2] Dosing valve according to claim 1, characterized by that the first sealing seat (20) can be flowed against through the inlet opening (31) formed in the radial direction (R) of a housing (35) of the metering valve (1) in the housing (35) of the metering valve (1), wherein the first sealing seat (20) and the second sealing seat (28) are fluidically connected to one another. [3] Dosing valve according to claim 1 or 2, characterized byin that the outlet opening (32) of the nozzle (14) is designed to discharge gas to the fuel cell in the region of the second sealing seat (28), wherein the second sealing seat (28) fluidically communicates with the first closure element (18) of the first sealing seat (20) via a first bore (34), and wherein the second sealing seat (28) has a second bore (37) fluidically communicating with the second closure element (26) of the second sealing seat (28). [4] Dosing valve according to one of the preceding claims, characterized by that a first air gap (38) is formed between the first armature (16) and a first housing element (36) of the housing (35) of the metering valve (1), and a second air gap (42) is formed between the second armature (24) and a magnetic core (40) of the metering valve (1), wherein the first air gap (38) has a smaller dimension than the second air gap (42). [5] Dosing valve according to one of the preceding claims, characterized bythat when a control current is applied to a magnetic coil (44) of the electromagnet (12), which is less than or equal to a predetermined threshold value, the first armature (16) is designed to open the first sealing seat (20) at least in sections, and the second armature (24) is designed to remain in a closed position. [6] Dosing valve according to claim 5, characterized by in that the first sealing seat (20) and the second sealing seat (28) can be opened independently, wherein upon application of a control current to the magnetic coil (44) of the electromagnet (12) which is greater than the predetermined threshold value, the first armature (16) is designed to remain in the open state and the second armature (24) is designed to open the first sealing seat (20) at least in sections. [7] Dosing valve according to one of the preceding claims, characterized byin that the first armature (16) is formed by a plate armature and the second armature (24) is formed by a plunger armature, wherein the first armature (16) is resettable by a first spring element (48) and the second armature (24) is resettable by a second spring element (50), wherein the first spring element (48) has a greater spring force than the second spring element (50). [8] Dosing valve according to one of the preceding claims, characterized by that the first closure element (18) is formed by the first anchor (16) or integrally with the first anchor (16), wherein a contact surface (52) of the first closure element (18) on the first sealing seat (20) has a sealing element (54) which is preferably formed from an elastomer material. [9] Dosing valve according to one of the preceding claims, characterized bythat a residual air gap disc (56) is arranged between the first armature (16) and the first housing element (36) of the housing (35) of the metering valve (1) to prevent magnetic adhesion of the first armature (16) to the first housing element (36) of the housing (35). [10] Dosing valve according to one of claims 4 to 9, characterized by that a sleeve (58) preferably made of a non-magnetic material is arranged between the second armature (24) and the first housing element (36) of the housing (35) of the metering valve (1), wherein the sleeve (58) is designed to magnetically separate the magnetic core (40) from the first housing element (36) of the housing (35). [11] Dosing valve according to claim 10, characterized bythat the sleeve (58) is designed to hold a second housing element (60) of the housing (35) of the metering valve (1) arranged adjacent to the first housing element (36) of the housing (35), and wherein the first armature (16) has an opening (62) through which a projection (64) of the second housing element (60) of the housing (35) extends. [12] Dosing valve according to claim 10, characterized by that the first armature (16) is arranged between an inner surface of a second housing element (60) of the housing (35) arranged adjacent to the first housing element (36) of the housing (35) and a projection (64) of the second housing element (60) of the housing (35), and can be guided on the inner surface of the second housing element (60) or on the projection (64) of the second housing element (60). [13] Fuel cell arrangement with a metering valve according to one of claims 1 to 12.

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