Foil axial bearing and method for assembling a foil axial bearing

Abstract

[Solution] The present invention relates to a foil axial bearing (1) having different bearing foils (11-14; 21-24) which are assembled in defined positions and in a specific sequence on two sides of an axial intermediate space (8). In order to simplify the assembly of the foil axial bearing (1), the different bearing foils (11-14; 21-24) are provided with additional identification marks which are visible on the different bearing foils (11-14; 21-24) under a defined identification mark sequence only when the different bearing foils (11-14; 21-24) are assembled and positioned correctly in the correct assembly sequence.

Description

[Technical Field]

[0001] The present invention relates to a foil axial bearing having different bearing foils assembled in defined positions and in a specific order on two sides of an axial intermediate space.Furthermore, the present invention relates to a method for assembling a foil axial bearing of this kind. [Background technology]

[0002] Patent document 1 discloses a rotor bearing system for a turbomachine, which includes at least the following: an axial foil air bearing having at least one top foil axially spaced from a support means and a bump foil arranged between the top foil and the support means; and a rotor abutting the axial foil air bearing and rotatable relative to the axial foil air bearing. From patent document 2, a foil axial bearing for a fuel cell system is known, which includes a thrust disk having at least one top foil circumferentially arranged above the thrust disk, and a bump foil arranged between the thrust disk and the top foil. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] German Patent Application Publication No. 102019200330A1 [Patent Document 2] German Patent Application Publication No. 102019200331A1 Summary of the Invention [Problem to be solved by the invention]

[0004] The object of the present invention is to simplify the assembly of foil axial bearings having different bearing foils which are assembled in defined positions and in a specific sequence on two sides of an axial intermediate space. [Means for solving the problem]

[0005] This problem is solved in a foil axial bearing having different bearing foils that are assembled in defined positions and in a specific order on two sides of an axial intermediate space by providing the different bearing foils with additional identification marks that are visible on the different bearing foils in a defined identification mark arrangement only when the different bearing foils are assembled in the correct assembly order and accurately positioned. In this way, it is possible to ensure in a simple manner that the different bearing foils can fully perform their assigned functions in the foil axial bearing. Preferably, the individual bearing foils with the additional identification marks are configured to enable error-proof assembly of the individual bearing foils.

[0006] A preferred embodiment of the foil axial bearing is characterized in that the different bearing foils are provided with viewing windows that are configured and positioned relative to the additional identifying marks of at least one respective bearing foil that is directly adjacent to one another in the correct assembly sequence, such that the additional identifying marks of at least two bearing foils that are directly adjacent to one another in the correct assembly sequence are visible in the assigned viewing windows only when the at least two bearing foils that are directly adjacent to one another in the correct assembly sequence are correctly assembled. In this way, correct positioning of the different bearing foils can be ensured in a simple manner not only in the case of manual assembly but also in the case of fully or partially automated assembly.

[0007] A preferred embodiment of the foil axial bearing is characterized in that the additional identification symbols are manufactured and arranged in such a way that the correct assembly sequence can be detected during assembly. Detection of the correct assembly sequence can be performed manually by the human eye and / or by a suitable camera system. Depending on the embodiment and configuration of the additional identification symbols combined with the viewing window, individual assembly steps can be checked. Alternatively, in some cases, the entire assembly sequence can be checked manually or automatically after the foil axial bearing has been assembled. Depending on the arrangement and embodiment of the additional identification symbols, the above-described viewing window can also be omitted in some circumstances. In that case, it must of course be ensured that the additional identification symbols can be detected in an appropriate manner when the foil axial bearing is in the assembled state.

[0008] A preferred embodiment of the foil axial bearing is characterized in that additional identification symbols and / or viewing windows are arranged in non-functional areas of the different bearing foils. This ensures that the desired functionality of the different bearing foils is not impaired when they are installed, for example, in a compressor of a fuel cell system. This has the advantage that retooling of the foil bearings can be performed cost-neutral, since the geometry is etched from the various coils. Therefore, additional engraved identification symbols and changes to the bolt hole circles of the different bearing foils do not significantly increase production costs. This has the advantage that only one adaptation of the negative mask for etching the different bearing foils is necessary, which results in negligible production costs.

[0009] A preferred embodiment of the foil axial bearing is characterized in that the additional identification symbols include letters, such as capital letters. The letters are preferably attached to the different bearing foils in a manner that makes them highly visible, and are highly visible both before and after installation. This significantly simplifies the assembly of the foil axial bearing.

[0010] A preferred embodiment of the foil axial bearing is characterized in that the additional identification symbol comprises a symbol, e.g., a dot, that can be automatically optically detected by a detection device. The automatically detectable symbol can, for example, comprise a different number of equally sized, highly visible dots. Automatically detectable symbols make automatic production, in particular mass production, particularly advantageous.

[0011] A preferred embodiment of the foil axial bearing is characterized in that the different bearing foils comprise two foil sets, each having a top foil, a stopper disc, a spacer disc, and a top disc. An adjustment disc, e.g., an intermediate ring, is arranged between the two foil sets to implement the intermediate space described above. The structure and design of foil axial bearings are known per se. The stopper disc, the spacer disc, and possibly also the adjustment disc may be formed from a foil-like material. In that case, these discs are also called foils. Preferably, both foil sets include identical components, which simplifies manufacturing. However, in some cases, assembly problems can be solved by additional identification, especially in combination with a viewing window.

[0012] A preferred embodiment of the foil axial bearing is characterized in that both foil sets are aligned via three asymmetrically arranged pins, which are attached to the bearing plates, for example. The claimed foil axial bearing preferably comprises two bearing plates of this type, between which both foil sets are arranged, together with an adjusting disc and, if necessary, an intermediate ring. Both foil sets are preferably sandwiched axially between the bearing plates, with the adjusting disc and intermediate ring interposed therebetween.

[0013] In the method for assembling foil axial bearings described above, the above problem is solved alternatively or additionally by checking whether the additional identification mark is visible and correctly positioned when assembling different bearing foils. The geometrical matching described above is implemented in different bearing foils, which may include, for example, additional identification marks and possibly also viewing windows, ensuring that different bearing foils are not assembled in the wrong installation position. Additionally, optical inspection of the correct assembly position and sequence of the different bearing foils is possible manually or with a suitable camera system. This avoids complaints and defects during product inspection or in the field of use due to incorrect assembly of axial foil bearings. This simplifies worker training. This allows for error-free assembly, especially when the assembly area is not visible or only has limited visibility.

[0014] The present invention also relates to a gas supply device, possibly having a rotor supported by the above-described foil axial bearing, which is preferably an air compressor driven by an electric motor, by which air is prepared in the fuel cell system.

[0015] The invention also relates, possibly, to a foil set, in particular a bearing foil, and / or a bearing plate for the above-described foil axial bearing, each of the above-described parts being separately addressable.

[0016] Other advantages, features and details of the invention will become apparent from the following description in which various embodiments are explained in detail with reference to the drawings. [Brief explanation of the drawings]

[0017] [Figure 1] 1A and 1B are exploded views showing foil axial bearings with different bearing foils. [Figure 2] FIG. 2 is a plan view showing the stopper disk of the foil axial bearing of FIG. 1 having a symmetrical hole arrangement. [Figure 3]3 is a bolt hole circle of the stopper disc shown in FIG. 2 to highlight the difference between the stopper disc of FIG. 2 and an embodiment of the stopper disc having an asymmetric hole arrangement; [Figure 4] FIG. 10 is a plan view showing a stopper disk having an asymmetric hole arrangement. [Figure 5] 2 is a schematic perspective view of the foil axial bearing of FIG. 1 in a perspective view with viewing windows of the different bearing foils; FIG. [Figure 6] FIG. 6 is a view similar to FIG. 5 with additional identifying marks on the different bearing foils. DETAILED DESCRIPTION OF THE INVENTION

[0018] Fig. 1 shows an exploded view of the foil axial bearing 1. Figs. 5 and 6 show the foil axial bearing 1 in a schematic perspective view to clearly show an embodiment of the foil axial bearing 1 having additional identification symbols 41-49 and / or viewing windows 50-60.

[0019] The foil axial bearing 1 includes two foil sets 10, 20. Each foil set 10, 20 includes a bump foil 11, 21, a stopper disc 12, 22, a spacer disc 13, 23, and a top foil 14, 24. The structure and function of this type of foil axial bearing 1 are known per se.

[0020] In the axial intermediate space 8 between the two foil sets 10 and 20, adjusting discs 30-39 and an intermediate ring 40 are arranged. The adjusting discs 30-39 serve to realize a defined distance between the two foil sets 10, 20.

[0021] Radially inside the adjusting discs 30-39, an axial bearing disc (not shown) is arranged which, when the foil axial bearing 1 is in the assembled state, serves to provide axial support for the rotor by the foil axial bearing 1, for example in the case of a compressor rotor. The axial bearing disc may be integrally connected to the shaft and may also be referred to as a disk-shaped region of the rotor.

[0022] The foil axial bearing 1 includes, in the assembled state, disk-shaped areas of the rotor on both sides, i.e., on the left and right sides as viewed in FIG. 1, radially within the adjusting discs 30-39 and the intermediate ring 40 in the axial intermediate space 8. The disk-shaped areas of the rotor or the axial bearing discs can be locked on the left and right sides when the foil axial bearing 1 is in the assembled state. Between the disk-shaped areas and the adjacent components there are foil sets 10, 20 of the foil axial bearing 1, respectively.

[0023] During assembly, for example on the left side, the bump foil 21, also called spring lamella or bump foil, is assembled first. In conventional foil axial bearings, the bump foil 21 is aligned via three pins housed in the bearing plate 6, which are offset from one another by 120 degrees in the circumferential direction.

[0024] Next, the stopper disk 22, also called the overstroke stopper disk, is assembled, followed by the spacer disk 23 and the top foil 24, also called the top foil. The top foil 24, in its correct assembled position, serves to create an air gap with the rotor's axial bearing disk, also called the rotor disk, during rotation in operation of the rotor.

[0025] On the right side, the bearing is constructed in a similar manner in accordance with the above. The generated and measured intermediate space 8 is covered by an appropriate number of adjusting discs 30-39. This ensures that all the different bearing foils or discs of the foil set 10, 20 are precisely and stably sandwiched between the two bearing plates 5, 6. A so-called intermediate ring 40 is also arranged between the top foil 24 and the adjusting disc 30.

[0026] Figure 2 shows that the stopper disc 22 can have a hole arrangement that is symmetrical about the line of symmetry 62, with symmetrically arranged positioning holes 67, 78, 79. Figure 4 clearly shows that the stopper disc 22 is preferably provided with an asymmetrical hole arrangement, with asymmetrically arranged positioning holes 77, 78, 79.

[0027] 2 and 4 it can be seen that the stopper disc 22 in both embodiments, i.e., with a symmetrical hole arrangement and with an asymmetrical hole arrangement, has a total of four threaded holes 63, 64, 65, 66. The threaded holes 63 to 66 serve to receive screws for mounting the foil axial bearing 1.

[0028] Furthermore, the stopper disc 22 comprises three locating holes 67; 78; 79 which are arranged symmetrically with respect to the line of symmetry 62 in Figure 2, whereas the locating holes 77-79 in Figure 4 are arranged intentionally asymmetrically. In addition to this, the stopper disc 22 is provided with an additional identifying symbol 48 in Figure 4.

[0029] The asymmetrical arrangement of the three pins and locating holes 77-79 prevents undesired misalignment of the foils or discs of the foil sets 10, 20. In addition, the asymmetrical arrangement of the locating holes 77-79 prevents undesired mixing up of the front and back sides during assembly.

[0030] Poka-yoke principles are applied to the mounting of each individual bearing foil of the foil sets 10, 20. In this way, consideration of the direction of rotation as well as the front and back surfaces of the bearing foils are completely eliminated during assembly.

[0031] 6 suggests that the foils and discs 11-14; 21-24 of the foil sets 10; 20 are provided with additional identification marks 41-49 according to one main aspect of the invention. The additional identification marks 41-49 are attached to the foil edges according to the respective technical drawings on which the design of the foil sets 10; 20 is based. The additional identification marks 41-49 preferably comprise fixedly assigned capital letters.

[0032] In one preferred embodiment, foils and discs 11-14, 30-39, 40, and 21-24 include the capital letters A, B / H, C / G, D, E, F, C / G, B / H, and J, which are in ascending order from bottom to top in Figure 6. These bearing foils or discs are assembled in ascending alphabetical order.

[0033] Figure 5 suggests that the bearing discs and bearing foils of the foil sets 10, 20 may further be provided with viewing windows 50-60 in addition to the additional identification marks 41-49 suggested in Figure 6. The viewing windows 50-60 are preferably provided in the edge regions of the foils or discs of the foil sets 10, 20.

[0034] The viewing windows 50-60 preferably serve to make it possible to recognize the foils or discs located or hidden thereunder, or additional identification symbols on these foils or discs, and are preferably dimensioned small to prevent misassembly with the three pins described above.

[0035] If both foil sets 10, 20 are properly assembled, a defined sequence of identification numbers, for example ABCDEFGHJ, also called a visibility pattern, results, which can preferably be inspected during assembly not only by the assembling personnel themselves, but also by a suitable camera system.

[0036] Alternatively, for camera checks, the letters described above can be replaced by corresponding dots as shown in Figure 6. The use of dots as additional identification symbols 41-49 simplifies optical detection by a suitable camera system.

[0037] It is particularly preferred that the stopper discs 12; 22, also called stroke stopper discs, and the spacer discs 13; 23 are manufactured as one and the same part. This is not adversely affected by the additional identification symbols B / H and C / G, since the unnecessary viewing windows and lettering are in principle covered by foils located above, below or next to them. [Explanation of symbols]

[0038] 1 Foil axial bearing 5,6 Bearing plate 8 Intermediate Space 10,20 foil set 11~14;21~24 Different bearing foils 41~49 Additional identification symbols 50~60 visibility window

Claims

1. A foil axial bearing (1) having different bearing foils (11-14; 21-24) assembled in defined positions and in a specific order on two sides of an axial intermediate space (8), 1. A foil axial bearing, characterized in that the different bearing foils (11-14; 21-24) are provided with additional identification marks (41-49) that are visible on the different bearing foils (11-14; 21-24) under a defined identification mark sequence only when the different bearing foils (11-14; 21-24) are assembled in the correct assembly sequence and accurately positioned.

2. 2. A foil axial bearing according to claim 1, characterized in that the different bearing foils (11-14; 21-24) are provided with viewing windows (50-60) positioned relative to the additional identifying marks (41-49) of at least one respective bearing foil that is directly adjacent to one another in the correct assembly sequence, such that the additional identifying marks of at least two bearing foils that are directly adjacent to one another in the correct assembly sequence are visible in the assigned viewing windows only when the at least two bearing foils that are directly adjacent to one another in the correct assembly sequence are correctly assembled.

3. 3. A foil axial bearing according to claim 1 or 2, characterized in that the additional identification marks (41-49) are manufactured and arranged in such a way that the correct assembly sequence can be detected during assembly.

4. 4. A foil axial bearing according to claim 1, wherein the additional identification symbols (41-49) and / or the viewing windows (50-60) are arranged in non-functionally relevant areas of the different bearing foils (11-14; 21-24).

5. A foil axial bearing according to any one of claims 1 to 4, characterized in that the additional identification symbols (41-49) comprise letters.

6. 6. A foil axial bearing according to any one of claims 1 to 5, characterized in that the additional identification symbols (41-49) comprise optical symbols, e.g. dots, that can be automatically detected by a detection device.

7. 7. A foil axial bearing according to claim 1, wherein the different bearing foils (11-14; 21-24) comprise two foil sets (10, 20), each having a top foil (11, 21), a stopper disc (12, 22), a spacer disc (13, 23) and a top disc (14, 24).

8. 8. A foil axial bearing according to claim 7, characterized in that both foil sets (10, 20) are aligned through three asymmetrically arranged pins.

9. 9. A method for assembling a foil axial bearing (1) according to any one of claims 1 to 8, characterized in that during the assembly of the different bearing foils (11-14; 21-24), it is checked whether the additional identification marks (41-49) are visible and correctly positioned.

10. A foil set (10, 20), in particular bearing foils (11-14; 21-24), and / or bearing plates (5, 6) for a foil axial bearing (1) according to any one of claims 1 to 8.

Images