MOUNTING DEVICE AND FUEL CELL SYSTEM

Description

[0001] The present invention relates to a fastening device for a fuel cell system for attaching a fuel cell stack of the fuel cell system to a base body of the fuel cell system. The invention further relates to a fuel cell system comprising a fuel cell stack with a negative feedback element, a base body, and at least one fastening device. State of the art

[0002] Known fuel cell systems consist of several layers of individual fuel cells in which hydrogen and atmospheric oxygen react across a membrane, generating an electrical voltage. The byproduct of the reaction is water. The total number of fuel cells forms a fuel cell stack. The total voltage of the fuel cell stack is the sum of the individual voltages of each fuel cell.

[0003] To protect the fuel cell stack from environmental influences and for safety reasons, the fuel cell stack is typically installed in a housing. This housing serves, among other functions, to contain and support the fuel cell stack. With a greater height of the fuel cell stack and the resulting higher mass, attachment to the base plate of the housing is no longer sufficient; it is also necessary to fix the fuel cell stack at the top. This is usually achieved using a floating bearing that allows the fuel cell stack movement in height (also defined as the Z-axis in the context of the invention) and fixes the fuel cell stack in the X and Y directions. This is advantageous because the fuel cell stack expands or contracts during operation due to temperature and internal pressure.Commonly used floating bearings consist, for example, of a spherical bearing bushing on the fuel cell stack side and a bearing bolt, a bearing flange, and an intermediate flange on the housing side. However, because the position of the spherical bearing within the fuel cell stack can cover a large range due to component tolerances, the flange is currently bonded to the intermediate flange, which is screwed into the housing cover. The screwing of the intermediate flange to the cover and the bonding process are challenging due to the materials and cleanliness requirements involved, and there is room for improvement.

[0004] In other bearing designs, direct bonding of the bearing flange to the housing cover is also known, thus eliminating the intermediate flange and the associated seal. However, the preparation and execution of the bonding process remain challenging and disadvantageous.

[0005] DE 10 2010 007981 A1 discloses a fuel cell arrangement with an upper end plate, a lower end plate, a plurality of fuel cells stacked between the upper end plate and the lower end plate, at least one clamping means acting between the upper end plate and the lower end plate for exerting a tensile force between the upper end plate and the lower end plate along a clamping direction, a fastening element for mechanical coupling between the clamping means and at least one of the end plates and / or between two clamping means, a coupling area in which the clamping means and the fastening element are connected to each other, wherein the fastening element is designed as an eccentric element or contains an eccentric element, wherein the eccentric element is rotatably mounted such that the coupling area can be moved in the clamping direction. Disclosure of the invention

[0006] The invention claims a fastening device for a fuel cell system for attaching a fuel cell stack of the fuel cell system to a base body of the fuel cell system, comprising the features of independent claim 1. Furthermore, the invention discloses a fuel cell system comprising a fuel cell stack with a negative feedback element, a base body, and at least one fastening device, according to the features of independent claim 8. Further advantages and details of the invention will become apparent from the dependent claims, the description, and the drawings. Features described in connection with the fastening device according to the invention naturally also apply in connection with the fuel cell system according to the invention, and vice versa, so that the disclosure regarding the individual aspects of the invention always refers, or can refer, to each other.

[0007] According to a first aspect of the invention, the invention discloses a fastening device for a fuel cell system for fastening a fuel cell stack of the fuel cell system to a base body of the fuel cell system. The fastening device has two fastening discs, wherein the first fastening disc can be fastened to the base body, wherein the second fastening disc is rotatably mounted on the first fastening disc about a first spatial axis and is arranged with a first eccentricity to the first fastening disc, wherein the second fastening disc has a coupling element for coupling with a feedback element of the fuel cell stack, wherein the coupling element is arranged with a second eccentricity to the second fastening disc, and wherein the two fastening discs can be immovably fastened to one another by at least one fixing means of the fastening device.

[0008] By combining the two mounting discs, it is possible to compensate for a variety of positional differences and / or deviations between the feedback element of the fuel cell stack and the coupling element, and / or to mechanically connect them securely. This significantly simplifies the assembly process of the fuel cell stack in the base body and allows for the use of standard screw connections, for example. The base body is preferably sealed using conventional O-rings.

[0009] By means of the two mounting discs, each with an eccentricity, it is possible to align the central axis of the coupling element and the central axis of the feedback element. During assembly, for example, the pre-assembled mounting device is installed in a cover of the base body by manually inserting and rotating it through two eccentric degrees of freedom. Once the desired position is reached, both mounting discs can be firmly connected to each other by means of at least one fixing element, such as a screw, to prevent any relative movement during operation of the fuel cell. The mounting device is preferably attached to the base body by means of a suitably designed retaining element, which is screwed firmly to the base body, particularly to the cover of the base body.

[0010] Within the scope of the invention, the fastening device preferably allows the coupling element to be displaced by up to the sum of both eccentricities. Furthermore, within the scope of the invention, additional fastening discs can be integrated into the fastening device. These additional fastening discs are to be understood as being arranged in a stepped manner relative to the first fastening disc, similar to the second, and are movable and fixed in this way. By way of example, a third fastening disc is rotatably arranged on the second fastening disc and has a third eccentricity. A key aspect of the invention is that the fastening discs can be fixed to one another in a non-movable manner and have at least one coupling element.

[0011] The first mounting washer is rotatably mounted on the base body about the first spatial axis in the detached state and immovably fixed to the base body in the fastened state. The second mounting washer is rotatably mounted on the first mounting washer about the first spatial axis in the detached state and immovably fixed to the first mounting washer in the fastened state.

[0012] The first eccentricity is to be understood in relation to the first mounting washer, and the second eccentricity is to be understood in relation to the second mounting washer.

[0013] Such a fastening device is particularly advantageous because it allows the fastening of the fuel cell stack of the fuel cell system to a base body of the fuel cell system in a particularly flexible and simple manner, especially by means of the two fastening discs.

[0014] According to a preferred embodiment of the invention, a fastening device may be provided in such a way that the second fastening disc is arranged at least partially, and in particular completely, within the first fastening disc. Arranging the second fastening disc at least partially, and in particular completely, within the first fastening disc advantageously saves installation space and allows for a particularly flat design of the fastening device. Additionally or alternatively, arranging the second fastening disc at least partially, and in particular completely, within the first fastening disc allows for advantageous height compensation between the coupling element and the feedback element.For the aforementioned arrangement of the second mounting washer, at least partially, and in particular completely, within the first mounting washer, the first mounting washer has a recess, depression, and / or a hole. The recess, depression, and / or hole are preferably at least partially cylindrical and / or conical in shape.

[0015] According to a preferred embodiment of the invention, a fastening device may be provided in which the first fastening disc and / or the second fastening disc are at least partially round and / or plate-shaped. A partially round design of the first fastening disc and / or the second fastening disc advantageously allows rotation while requiring minimal installation space. Furthermore, a round design of the first fastening disc and / or the second fastening disc allows for advantageous guidance of the fastening discs against each other and / or of the first fastening disc against the base body. A plate-shaped design of the first fastening disc and / or the second fastening disc advantageously allows for a flat design of the fastening device and thus requires minimal installation space.

[0016] According to a preferred embodiment of the invention, a fastening device may be provided in such a way that the coupling element is designed as a bearing bushing or bearing bolt and is configured for coupling with a bearing bushing or bearing bolt of the fuel cell stack. The design of the coupling element and the feedback element is preferably functionally interchangeable in the sense of kinematic inversion. Within the scope of the invention, the coupling element and the feedback element constitute two halves of a coupling device and serve to guide and / or secure the position of the fuel cell stack on the base body. By way of example, the coupling element is designed as a bearing bushing. In this example, the fuel cell stack has a bearing bolt as a feedback element for coupling with the coupling element.The coupling element and the feedback element preferably have a positive fit.

[0017] According to a preferred embodiment of the invention, a fastening device may be provided such that the value of the first eccentricity corresponds to the value of the second eccentricity. Within the scope of the invention, eccentricity is to be understood as the distance between two centers and / or central axes of the corresponding components and / or devices. If the first and second eccentricities are equal, a coupling element arranged centrally with respect to the first fastening washer is advantageously enabled. The two eccentricities are arranged opposite each other for the purpose of this central arrangement. The maximum distance and / or displacement of the coupling element and / or the central axes is therefore up to twice the value of one of the eccentricities. For the maximum displacement, the two eccentricities are preferably arranged along a line.

[0018] According to a preferred embodiment of the invention, a fastening device may be provided in which the two fastening discs each have a thickness along the first spatial axis, wherein the thickness of the first fastening disc corresponds to the thickness of the second fastening disc or substantially corresponds to the thickness of the second fastening disc, or the thickness of the first fastening disc is greater than the thickness of the second fastening disc. The phrase "X or substantially X" is to be understood within the scope of the invention as a possible, minor deviation, for example, due to manufacturing tolerances, material and / or process properties, without altering the underlying, intended function of the feature. Preferably, the two fastening discs are arranged flush with the surface on at least one side, in particular a side facing the fuel cell stack.If the first and second mounting washers have the same thickness, they are preferably arranged flush on both sides. In an embodiment where the thickness of the first mounting washer is greater than that of the second, the second mounting washer is preferably arranged in a recess in the first mounting washer. The recess in the first mounting washer preferably provides a guide and / or a stop for the second mounting washer.

[0019] According to a preferred embodiment of the invention, a fastening device may be provided in which the second fastening washer is positively locked and / or coplanarly mounted in the first fastening washer. A positively locked configuration of the second fastening washer relative to the first fastening washer, in particular relative to a recess in the first fastening washer, enables advantageous guidance and / or a close fit of the fastening washer to one another. Additionally or alternatively, advantageous, in particular uniform and / or smooth, movement of the second fastening washer is enabled. Within the scope of the invention, a coplanar arrangement of the fastening washer to each other is to be understood as a coplanar arrangement of the fastening washer, at least of each surface of the fastening washer, and / or of each principal plane of extension of the fastening washer.A fastening device designed in this way is particularly advantageous because it allows for the attachment of the fuel cell stack of the fuel cell system to a base body of the fuel cell system in a particularly flexible and simple manner, especially by the fact that the second fastening disc is positively locked and / or coplanarly mounted in the first fastening disc.

[0020] According to a second aspect of the invention, the invention discloses a fuel cell system comprising a fuel cell stack with a feedback element, a base body, and at least one mounting device according to the first aspect. The first mounting disc is attached to the base body, and the fuel cell stack is coupled to the mounting device via the coupling element and the feedback element. The described fuel cell system offers all the advantages already described for the mounting device according to the first aspect of the invention. The base body is preferably designed as a housing, in particular with a cover, for the fuel cell system.A fuel cell system designed in this way is particularly advantageous because the fastening of the fuel cell stack of the fuel cell system to the base body of the fuel cell system is made particularly flexible and easy by the fastening device, in particular by the two fastening discs.

[0021] According to a preferred embodiment of the invention, a fuel cell system can be provided with a base body comprising at least one receiving device, wherein the first mounting disc is arranged and / or fastened in the receiving device. Preferably, the receiving device has a depth corresponding to the thickness of the first and / or second mounting disc. A receiving device advantageously enables position securing and / or position finding for the first mounting disc on and / or in the base body. By designing the receiving device as a recess in the base body, a small installation space requirement and / or a slim design of the fuel cell system is advantageously achieved.

[0022] According to a preferred embodiment of the invention, a fuel cell system may be provided in such a way that the fastening device, in particular the coupling element and the feedback element, has one degree of freedom for movement of the fuel cell stack along the first spatial axis. Preferably, however, the fastening device enables the fastening and / or restriction of the degrees of freedom for movement of the fuel cell stack along the second and third spatial axes, in particular by means of the at least one fixing means of the fastening device.A fastening device designed in this way is particularly advantageous because it allows the fuel cell stack of the fuel cell system to be attached to a base body of the fuel cell system in a particularly flexible and simple manner, and it allows movement of the fuel cell stack along the first spatial axis, for example by expansion and / or heating.

[0023] According to a preferred embodiment of the invention, a fuel cell system may be provided in such a way that the two mounting discs can be fixedly fastened to each other and / or to the base body by means of at least one fixing element of the fastening device. Preferably, the at least one fixing element enables the two mounting discs to be fixedly fastened to each other and / or to the base body.

[0024] A fastening device according to the invention and a fuel cell system are explained in more detail below with reference to the drawings. The drawings schematically show: Figure 1 in a combined top and side view shows a fuel cell system with a mounting device, Figure 2 in a side view shows a fuel cell system with a mounting device, and Figure 3 in a side view shows a fuel cell system with a mounting device.

[0025] Elements with the same function and mode of operation are in the Fig. 1 bis 3 each provided with the same reference numerals.

[0026] In Fig. 1 A fuel cell system 100 with a mounting device 10 is shown schematically in a combined top and side view. The fuel cell system 100 comprises a fuel cell stack 110 with a negative feedback element 112, a base body 120, and a mounting device 10. The mounting device 10 has two mounting discs 20, 30, wherein the first mounting disc 20 can be attached to the base body 120, and wherein the second mounting disc 30 is rotatably mounted on the first mounting disc 20 about a first spatial axis Z and is arranged with a first eccentricity E1 to the first mounting disc 20.The second mounting disc 30 has a coupling element 32 for coupling with the feedback element 112 of the fuel cell stack 110, wherein the coupling element 32 is arranged with a second eccentricity E2 relative to the second mounting disc 30, and wherein the two mounting discs 20, 30 can be immovably fastened to one another by means of a fixing means 40 of the mounting device 10. The first mounting disc 20 can be fastened to the base body 120, and the fuel cell stack 110 is coupled to the mounting device 10 via the coupling element 32 and the feedback element 112. The second mounting disc 30 is arranged completely within the first mounting disc 20. The first mounting disc 20 and the second mounting disc 30 are round and plate-shaped, respectively.The coupling element 32 is designed as a bearing bushing and is configured for coupling with a bearing bolt as a feedback element 32 of the fuel cell stack 110. The second mounting disc 30 is positively and coplanarly mounted in the first mounting disc 20. The base body 120 comprises a receiving device 122, wherein the first mounting disc 20 is arranged and fixed in the receiving device 122. The mounting device 10, specifically the coupling element 32 and the feedback element 112, have one degree of freedom for movement of the fuel cell stack 110 along the first spatial axis Z. The two mounting discs 20, 30 are fixedly fastened to each other and to the base body 120 by the fixing means 40 of the mounting device 10.

[0027] In Fig. 2 A fuel cell system 100 with a mounting device 10 is shown schematically in a side view. The value of the first eccentricity E1 corresponds to the value of the second eccentricity E2. Fig. 2 The maximum displacement of the coupling element 32 through the two eccentricities E1, E2 is shown. The two mounting discs 20, 30 each have a thickness D1, D2 along the first spatial axis Z, where the thickness D1 of the first mounting disc 20 is greater than the thickness D2 of the second mounting disc 30.

[0028] In Fig. 3 A fuel cell system 100 with a mounting device 10 is shown schematically in a side view. Fig. 3 The centering of the coupling element 32 is shown by the opposing arrangement of the two eccentricities E1, E2.

Claims

1. Fastening device (10) for a fuel-cell system (100) for fastening a fuel-cell stack (110) of the fuel-cell system (100) to a main body (120) of the fuel-cell system (100), the fastening device (10) having two fastening discs (20, 30), wherein the first fastening disc (20) is able to be fastened to the main body (120), wherein the second fastening disc (30) is mounted on the first fastening disc (20) so as to be rotatable about a first spatial axis (Z) and is arranged with a first eccentricity (E1) in relation to the first fastening disc (20), wherein the second fastening disc (30) has a coupling element (32) for coupling to a counterpart coupling element (112) of the fuel-cell stack (110), wherein the coupling element (32) is arranged with a second eccentricity (E2) in relation to the second fastening disc (30), and wherein the two fastening discs (20, 30) are able to be fastened immovably to one another by way of at least one fixing means (40) of the fastening device (10).

2. Fastening device (10) according to Claim 1, characterized in that the second fastening disc (30) is arranged at least partially, in particular completely, within the first fastening disc (20).

3. Fastening device (10) according to either of the preceding claims, characterized in that the first fastening disc (20) and / or the second fastening disc (30) are / is of at least sectionally round and / or plate-shaped form.

4. Fastening device (10) according to either of the preceding claims, characterized in that the coupling element (32) is in the form of a bearing bush or bearing pin and is configured for coupling to a bearing bush or bearing pin of the fuel-cell stack (110).

5. Fastening device (10) according to either of the preceding claims, characterized in that a value of the first eccentricity (E1) corresponds to a value of the second eccentricity (E2).

6. Fastening device (10) according to either of the preceding claims, characterized in that the two fastening discs (20, 30) each have a thickness (D1, D2) along the first spatial axis (Z), wherein the thickness (D1) of the first fastening disc (20) corresponds to the thickness (D2) of the second fastening disc (30) or the thickness (D1) of the first fastening disc (20) is greater than the thickness (D2) of the second fastening disc (30).

7. Fastening device (10) according to either of the preceding claims, characterized in that the second fastening disc (30) is mounted in a form-fitting and / or coplanar manner in the first fastening disc (20).

8. Fuel-cell system (100) having a fuel-cell stack (110) with a counterpart coupling element (112), having a main body (120) and having at least one fastening device (10) according to one of the preceding claims, wherein the first fastening disc (20) is fastened to the main body (120), and wherein the fuel-cell stack (110) is coupled via the coupling element (32) and the counterpart coupling element (112) to the fastening device (10).

9. Fuel-cell system (100) according to Claim 8, characterized in that the main body (120) comprises at least one receiving device (122), wherein the first fastening disc (20) is arranged and / or fastened in the receiving device (122).

10. Fuel-cell system (100) according to Claim 8 or 9, characterized in that the fastening device (10), in particular the coupling element (32) and the counterpart coupling element (112), has a degree of freedom for a movement of the fuel-cell stack (110) along the first spatial axis (Z).

11. Fuel-cell system (100) according to one of Claims 8 to 10, characterized in that the two fastening discs (20, 30) are able to be fastened immovably to one another and / or to the main body (120) by way of at least one fixing means (40) of the fastening device (10).