BEARING CAGE SEGMENT OF A SHEET METAL CAGE

Abstract

A sheet metal bearing cage segment includes a first sheet metal ring section, at least one second sheet metal ring section, and a plurality of bridges connecting the first ring section and the at least one second ring section to each other, adjacent pairs of the bridges forming pockets configured to receive at least one rolling element. At least one edge of the first ring section and/or at least one edge of the at least one second ring section and/or of one of the bridges is at least partially formed by laser cutting. Also a method of forming a sheet metal bearing cage at least partially by laser cutting.

Claims

1. A sheet metal bearing cage segment comprising: a first sheet metal ring section; at least one second sheet metal ring section; a plurality of bridges connecting the first ring section and the at least one second ring section to each other, adjacent pairs of the bridges forming pockets configured to receive at least one rolling element, wherein at least one edge of the first ring section and/or at least one edge of the at least one second ring section and/or of one of the bridges is at least partially formed by laser cutting.

2. The bearing cage segment according to claim 1, wherein the at least one edge comprises at least a part of an outer contour of the bearing cage segment.

3. The bearing cage segment according to claim 1, wherein the at least one pocket is formed by punching.

4. The bearing cage segment according to claim 1, wherein the at least one edge is a joint edge directed in the circumferential direction and disposed in a region of one of the pockets or in a region of one of the bridges.

5. The bearing cage segment according to claim 1, wherein the bearing cage segment includes a first end region and a second end region circumferentially spaced from the first end region and a substantially planar region between the first end region and the second end region, wherein the first end region is pre-bent to a radius of curvature of the sheet metal cage without bending the substantially planar region.

6. The bearing cage segment according to claim 1, wherein at least one of the bridges and/or the first ring section and/or the at least one second ring section includes guide structures for guiding a rolling element, the structures being formed by stamping and/or rolling.

7. The bearing cage segment according to claim 1, wherein an outer contour of the bearing cage segment includes at least one micro-connection point, to which the bearing cage segment is connected during manufacturing to a metal sheet from which the bearing cage segment is manufactured, wherein a first micro-connection point is disposed on the axially outer edge of the first ring section, and a second micro-connection point is disposed on the axially outer edge of the at least one second ring section.

8. The bearing cage segment according to claim 7, wherein an outer contour of the bearing cage segment includes at least one micro-connection point, to which the bearing cage segment is connected during manufacturing to a metal sheet from which the bearing cage segment is manufactured, wherein a first micro-connection point is disposed on the axially outer edge of the first ring section, and a second micro-connection point is disposed on the axially outer edge of the at least one second ring section.

9. A sheet metal cage for a needle roller bearing including at least one bearing cage segment according to claim 1.

10. The sheet metal cage according to claim 8, wherein a joint edge of the at least one bearing cage segment, which joint edge is directed in the circumferential direction, is connected via a material-bonded, interference-fit, or friction-fit connection to a further joint edge of the bearing cage segment or a further joint edge of a further bearing cage segment by a weld connection.

11. A method for manufacturing a sheet metal bearing cage segment comprising: providing a metal sheet, laser cutting at least part of a bearing cage in the metal sheet.

12. The method according to claim 11 including before the laser cutting, punching a plurality of pockets in the metal sheet.

13. The method according to claim 12, including forming at least one guide surface in the pockets for guiding rolling elements, wherein laser cutting includes leaving the bearing cage attached to the metal sheet by at least one micro-connection point, and releasing the bearing cage segment from the metal sheet by breaking the at least one micro-connection point.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG. 1 is a schematic depiction of a first preferred exemplary embodiment of a bearing cage segment,

[0032] FIG. 2 is a schematic representation of a second exemplary embodiment of a bearing cage segment,

[0033] FIG. 3 is a plan view of a metal sheet including a plurality of shaped bearing cage segments,

[0034] FIG. 4 is a detail of FIG. 3 about an end region of the bearing cage segment,

[0035] FIG. 5 is a perspective representation of a bearing cage segment having two pre-bent end regions,

[0036] FIG. 6 is a perspective representation of a further preferred exemplary embodiment including stamped bridges, and

[0037] FIG. 7 is a perspective representation of a further exemplary embodiment including rolled and stamped bridges.

DETAILED DESCRIPTION

[0038] In the following, identical or functionally equivalent elements are designated by the same reference numbers. The direction designations used in the followingaxial, radial, circumferentialalways refer to the finished bearing cage.

[0039] FIG. 1 shows a schematic representation of a first exemplary embodiment of a bearing cage segment 1. The bearing cage segment 1 includes a first ring section 2, a second ring section 3, and a plurality of bridges 4 connecting the first ring section 2 and the second ring section 3 to each other, wherein pockets 5 for receiving rolling elements (not depicted) are formed between the bridges 4. Such a bearing cage segment 1 can be manufactured, for example, from a large-area metal sheet and is suitable in particular for a needle roller bearing. Instead of the single-row design of the bearing cage segment 1 depicted here, the bearing cage segment 1 can also be configured multi-row, and would then include a first, a second, and further ring sections that are each connected to each other by bridges.

[0040] As schematically indicated by thick lines in FIG. 1, the outer contour K of the bearing cage segment is formed by laser cutting. Here this outer contour comprises, inter alia, an axially outer edge 8 of the first ring section 2 and an axially outer edge 9 of the second ring section 3.

[0041] In the depicted exemplary embodiment the outer contour K further respectively comprises joint edges 10-1, 10-2 of the first ring section 2, which joint edges 10-1, 10-2 are directed in the circumferential direction, and are either joined together or to a further joint edge of a further bearing cage segment via a connection, for example, a weld connection, in order to form the finished bearing cage. The second ring region 3 includes corresponding joint edges 11-1, 11-2.

[0042] In the embodiment sketched in FIG. 1 the joint edges 10, 11 are provided in the region of a to-be-formed pocket 50, that is, of a so-called welding pocket. This to-be-formed pocket 50 thus includes a first partial pocket 50-1 and a second partial pocket 50-2 that in the assembled state the has the same dimensions as the other pockets 5. The partial pocket 50-1 itself comprises a bridge edge 13, an axially inner-edge section 12 of the first ring section 2, and an axially inner-edge section of the second ring section 3. This contour of the partial pocket 50-1 is preferably also laser-cut. The partial pocket 50-2 can be configured analogously.

[0043] As sketched in FIG. 2, according to an alternative exemplary embodiment a joint edge, here provided with the reference numeral 15-1, can be disposed in the region of a bridge or of a to-be-formed bridge, so that in this case a partial bridge 40-1 is formed. This joint edge 15-1 forms, so to speak, a partial-bridge joint edge. Due to this design a joint edge can be obtained that is significantly larger than the joint edges 10-1, 11-1 shown in FIG. 1, whereby a particularly stable connection can be achieved.

[0044] Analogously the bearing cage segment 1 of FIG. 2 includes a partial bridge 40-2 on its other side, wherein the partial bridge 40-1 and the partial bridge 40-2 are dimensioned such that in the assembled state they form a weld bridge 40 that has approximately the same dimensions as the other bridges 4.

[0045] In the above-mentioned exemplary embodiments the normal pockets 5 are preferably formed by punching. Here this punching of the pockets 5 can be effected prior to or after the laser cutting of the outer contour. However, punching prior to the laser cutting is preferred since the metal sheet still has greater stability here. For the same reason, a possible stamping and/or rolling of the bridges, which is to be discussed in more detail below, can also preferably be carried out prior to the laser cutting of the outer contour.

[0046] The great advantage with combined laser cutting/punching or only with laser cutting is that, as shown by way of example in FIG. 3, the bearing cage segment can easily be cut-out from a large-area metal sheet 7. Here a plurality of bearing cage segments 1 can be obtained from the metal sheet 7 which, as shown in FIG. 3, are uniformly dimensioned. However, it is also possible that these bearing cage segments 1 differ in their dimensions.

[0047] In order to form a spatial fixing of the bearing cage segment 1 or of the bearing cage segments 1 for, for example, steps occurring after the laser cutting, such as punching, bending, rolling, stamping, and to improve the handleability of the bearing cage segments 1, the individual bearing cage segments 1 can, as indicated in the exemplary embodiment shown in FIG. 5 based on a bearing cage segment already separated from the metal sheet 7, preferably each be connected to the rest of the metal sheet 7 via micro-connection points. These micro-connection points 17 are only detached when the respective bearing cage segment 1 is needed. The micro-connection points 17 are preferably configured such that a detaching of the bearing cage segment from the metal sheet 7 is possible by a simple manual breaking of the micro-connection points 17. Mechanical and/or machine breaking or removing is also possible.

[0048] In order to also facilitate storing and handling or the subsequent further processing, a plurality of bearing cage segments can be grouped into a cluster 16, wherein stabilizing sheet metal regions 25 are formed between the clusters 16. To provide one of the bearing cage segments it can be provided that first the respective cluster 16 is completely released from the rest of the metal sheet 7, and in a subsequent step the desired bearing cage segment 1 is separated from the rest of the cluster 16.

[0049] FIG. 4 shows a detail of FIG. 3 around an end region of the bearing cage segment according to a further exemplary embodiment. As shown, a recess 18 can be formed at the circumferential end of the bearing cage segment, here also referred to as sacrificial pocket 18, by which a contour is formed that corresponds in its basic shape to the corresponding contour of the partial pocket 50-1 shown in FIG. 1. However, this recess 18 can be punched in accordance with an exemplary embodiment. For this purpose a corresponding punching tool can be provided. Here the recess 18 is preferably configured such that it extends axially outward over the ring sections 2, 3. The joint edges 10-1 and 11-1 of the ring sections 2 can thereby also be produced particularly flatly by punching. However, in this example the axially outer edges 8, 9 of the ring sections 2, 9 are laser-cut, wherein the laser cuts open directly into the recess 18 in order to obtain a largest-possible variability in the width of the bearing cage segment 1.

[0050] In the exemplary embodiment shown in FIG. 5, the bearing cage segment 1 includes an end region 19, 20 at each of its circumferential ends, which is pre-bent to the radius of curvature of the finished sheet metal cage. The bending of the bearing cage segment 1 overall to the provided radius of curvature is thereby made easier.

[0051] The pre-bent end regions 19, 20 can advantageously be produced by stamping, in particular while the bearing cage segment 1 is still connected to the rest of the metal sheet 7 via the micro-connection points 17.

[0052] As furthermore shown by way of example in FIG. 5, guide surfaces 21 for guiding the rolling elements can be formed on the bridges 4. In the embodiment shown in FIG. 5, these guide surfaces 21 extend over the entire radial thickness of the bridges 4. Thus these guide surfaces 21 can be formed, for example, in the course of the punching of the pockets 5.

[0053] The ring sections 2, 3 can also include correspondingly formed guide surfaces 22.

[0054] In the example shown in FIG. 5, the bridges 4 have a uniform radial thickness at all points. The ring sections 2, 3 also have a uniform thickness that is identical here to the thickness of the bridges 4.

[0055] FIG. 6 shows details of a further preferred exemplary embodiment of a bearing cage segment 1, wherein the bridges 4 do not have uniform thickness. Rather, the bridges 4 have stamped and/or rolled and/or milled regions 23 here by which regions 23 guide surfaces are formed for the rolling elements. Here the ring sections 2, 3 can include guide surfaces 22 as are described above with reference to FIG. 5.

[0056] FIG. 7 shows a further preferred embodiment wherein the bridges include regions 23 formed by rolling and/or stamping, which regions 23 extend farther radially inward than the ring sections 2, 3. These bridge regions 23 can in turn include corresponding guide surfaces 21 for the rolling elements. The bridge regions 23 are connected to the ring sections via bridge regions 24. Alternatively the bridge regions 23 can be configured extending radially outward.

[0057] One of the following sequences can preferably be provided for the order of the steps for forming the bridges shown in FIGS. 5 and 6:

[0058] rolling/stamping-punching-laser cutting

[0059] punching-laser cutting-rolling/stamping

[0060] punching-rolling/stamping-laser cutting

[0061] If the punching is carried-out prior to the laser cutting, it can be achieved that the bearing cage segment will remain particularly stably connected to the metal sheet during the punching process.

[0062] In summary a bearing cage segment can be manufactured particularly economically by the bearing cage segment being at least partially laser-cut, whereby an individual manufacturing is possible without tools that are specifically matched to the dimensions of the bearing cage segment. Due to pre-bent end regions of the bearing cage the bearing cage segment can be more easily bent out of a plane into the radius of curvature specified for the finished cage. The bearing cage segment can advantageously be manufactured from a metal sheet, wherein during manufacturing it is still connected to the rest of the metal sheet via micro-connection points.

[0063] Representative, non-limiting examples of the present invention were described above in detail with reference to the attached drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present teachings and is not intended to limit the scope of the invention. Furthermore, each of the additional features and teachings disclosed above may be utilized separately or in conjunction with other features and teachings to provide improved bearing cages.

[0064] Moreover, combinations of features and steps disclosed in the above detailed description may not be necessary to practice the invention in the broadest sense, and are instead taught merely to particularly describe representative examples of the invention. Furthermore, various features of the above-described representative examples, as well as the various independent and dependent claims below, may be combined in ways that are not specifically and explicitly enumerated in order to provide additional useful embodiments of the present teachings.

[0065] All features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter, independent of the compositions of the features in the embodiments and/or the claims. In addition, all value ranges or indications of groups of entities are intended to disclose every possible intermediate value or intermediate entity for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter.

REFERENCE NUMBER LIST

[0066] 1 Bearing cage segment [0067] 2 First ring section [0068] 3 Second ring section [0069] 4 Bridges [0070] 40 Partial bridge [0071] 5 Pockets [0072] 50 Partial pocket [0073] 7 Metal sheet [0074] 8 Axially outer edge of the first ring section [0075] 9 Axially outer edge of the second ring section [0076] 10 Joint edge of the first ring section [0077] 11 Joint edge of the second ring section [0078] 12 Axially inner edge section of the first ring section [0079] 13 Bridge edge [0080] 14 Axially inner edge region of the second ring section [0081] 15 Partial-bridge joint edge [0082] 16 Cluster of bearing cage segments [0083] 17 Micro-connection points [0084] 18 Recess, sacrificial pocket [0085] 19 First end region of a bearing cage segment [0086] 20 Second end region of the bearing cage segment [0087] 21 Guide surfaces of the bridges [0088] 22 Guide surfaces of the ring sections [0089] 23 Stamped/rolled regions of the bridges [0090] 24 Bridge regions [0091] 25 Stabilizing metal sheet regions