Axiallager

Abstract

Axial bearing comprising an annular rolling element arrangement (2) with several needle- or roller-shaped rolling elements (5) guided on a cage (3), characterized in that the rolling elements (5) each have a central opening (6), wherein the annular cage (3) formed from wire (4) has a plurality of loop- or clamp-shaped retaining sections (7, 15) which extend through the openings (6).

Description

[0001] The invention relates to an axial bearing comprising an annular rolling element arrangement with several needle- or roller-shaped rolling elements guided on a cage.

[0002] Such an axial bearing typically features a rolling element arrangement comprising a number of mostly needle-shaped or roller-shaped rolling elements that roll on corresponding raceways, usually formed by two separate bearing rings. The rolling elements are guided on or within a cage.

[0003] Such a cage can be made of a plastic, as in the axial bearing known from US 3,811,744 A. Alternatively, such a cage can also be made of strip steel. The cage typically has pockets into which the individual rolling elements are inserted. Manufacturing such cages requires the use of a relatively large amount of material, whether plastic or metal. DE 21 50 982 A discloses an axial bearing in which the cage is formed from a wire that is bent in a complex manner, so that wire loops create pocket-like recesses that surround the rolling elements on the outside. The construction of such a cage is very complex, and the cage is relatively fragile overall.

[0004] The invention is based on the problem of providing an improved rolling bearing with a simply designed cage.

[0005] To solve this problem, in an axial bearing of the type mentioned above, the invention provides that the rolling elements each have a central opening, wherein the ring-shaped cage formed from wire has a plurality of loop- or clamp-shaped retaining sections that engage the rolling elements in the openings.

[0006] In the axial bearing according to the invention, comprising an annular rolling element arrangement with several needle- or roller-shaped rolling elements, each having a central opening, the rolling elements are rotatably held on a guide wire that extends through the opening and defines a ring shape. The axial bearing according to the invention is therefore characterized by a wire cage that does not have pockets, but rather loop- or clamp-shaped retaining sections on which the needle- or roller-shaped rolling elements are held and rotatably guided. The rolling elements are threaded onto the retaining sections, with each rolling element having a central opening extending axially through it, which is penetrated by the respective retaining section. As a result of this threading and penetration, the individual rolling elements are securely held, guided, and rotatably mounted.

[0007] The wire cage itself is extremely simple in design. Firstly, it uses a basic wire material, allowing the cage to be manufactured with very little material. Secondly, its geometric shape, with loop- or clamp-shaped retaining sections, is simple, eliminating the need for complex bending structures. Overall, this results in a sustainable cage design, both in terms of material usage and manufacturing process.

[0008] Preferably, the openings are designed as bores, i.e., they have a cylindrical cross-section, and a round wire, also with a cylindrical cross-section, is used. The respective cylindrical cross-sections ensure good rotation of the rolling elements on or around the holding section.

[0009] According to a first embodiment of the invention, the wire forming the cage can be endless and meander in shape, forming loop-shaped retaining sections with straight longitudinal legs and a connecting transverse leg. The wire, formed into a ring shape, is thus bent in a meandering shape and has consecutive, U-shaped, loop-shaped retaining sections in the circumferential direction. Each of these retaining sections has two straight longitudinal legs and a connecting transverse leg, with the rolling elements arranged on the longitudinal legs. The ends of the meandering wire are joined together in a suitable manner, for example by butt welding.

[0010] It is conceivable that a rolling element is arranged on each longitudinal leg. This requires that the longitudinal legs are sufficiently far apart in the circumferential direction so that the rolling elements do not touch each other. Alternatively, it is also conceivable that a rolling element is arranged only on every other longitudinal leg. This allows the loop-shaped retaining sections to be bent more tightly.

[0011] According to a second embodiment of the invention, the cage can be formed by means of several individual U-shaped clamps, each forming a clamp-like holding section and having two straight longitudinal legs and a connecting transverse leg, wherein each longitudinal leg extends through an opening in a rolling element and wherein each opening is penetrated by two longitudinal legs of two adjacent clamps. In this embodiment, therefore, no continuous wire is used, but rather a corresponding number of individual U-shaped clamps, each representing a clamp-like holding section. Each clamp has two straight longitudinal legs and a connecting transverse leg. The clamps are arranged directly next to each other in the circumferential direction, with each opening in a rolling element being penetrated by two immediately adjacent or abutting longitudinal legs of two adjacent clamps.The opening in this variant, with the same wire diameter, has a slightly larger diameter than in the first variant, since two longitudinal legs must be accommodated in the opening. In this variant as well, a ring shape can be easily formed by bending the fully assembled clip chain into a ring shape.

[0012] For easy fixation of the rolling elements to the longitudinal legs that penetrate them, the ends of the longitudinal legs protruding from the openings are bent over so that they slightly overlap or encircle the end face of the respective rolling element, thus providing a radial boundary. Preferably, the ends of two longitudinal legs penetrating an opening are bent in opposite directions.

[0013] Preferably, the U-shaped clips are arranged such that the transverse legs are positioned radially outside the annular rolling element arrangement. This means that the clips are inserted into the openings of the rolling elements from the outside.

[0014] Both invention variants therefore allow for the construction of a simply designed and easily manufactured wire cage using minimal cage material, since only a thin, round metal wire is used, which is formed simply without the need for complex bending structures. The wire cage formed in this way is also sufficiently stable. Because the bearing is under load during operation, the rolling elements are automatically aligned according to their orbit and remain on this path during rotation.

[0015] In addition to the axial bearing itself, the invention further relates to a method for manufacturing a rolling element assembly for an axial bearing. One method for manufacturing a rolling element assembly with a continuous wire provides that individual rolling elements, each having a centrally penetrating opening, are successively threaded onto a straight wire. After each rolling element is threaded, the wire is bent in a meandering shape to form loop-shaped retaining sections. After the last rolling element is threaded, the wire is bent into a ring shape and its ends are positively connected to each other, in particular by butt welding. The starting point is therefore a straight wire, preferably a round wire, onto which the individual rolling elements are successively threaded.During this threading process, the wire is bent accordingly using a suitable bending device, so that the U-shaped, loop-like retaining sections are formed. Once the last rolling element has been threaded, the still straight rolling element assembly is simply bent into a ring shape, after which the two wire ends are joined together to form a continuous wire, preferably by butt welding.

[0016] A method for manufacturing a rolling element assembly with a wire cage formed from a plurality of individual U-shaped clips involves threading the rolling elements, each having a centrally penetrating opening, onto the longitudinal legs of individual U-shaped wire clips. Two longitudinal legs pass through each opening of a rolling element. After threading the penultimate rolling element, the assembly is bent into a ring shape, and the two free longitudinal ends of the first and last clips are guided through the opening of the last rolling element. The ends of the longitudinal legs protruding from the openings are bent over during or after threading. In this variant, too, a straight rolling element assembly is initially formed by threading the individual rolling elements onto the U-shaped clips arranged side by side in a straight line.In this process, two adjacent longitudinal legs of two adjacent clips pass through a rolling element opening. The longitudinal leg of the first clip and the longitudinal leg of the last clip initially remain unused. Once the penultimate rolling element is threaded, the rolling element assembly is bent into a ring shape so that the two remaining unused longitudinal legs of the first and last clips lie parallel to each other, after which the last rolling element is threaded onto these two longitudinal legs. The radial fixation of the rolling elements to the longitudinal legs is achieved by bending over the ends protruding from the openings; this bending can occur during the threading process or only after the threading is complete.

[0017] The invention is explained below with reference to exemplary embodiments and the drawings. The drawings are schematic representations and show: Fig. 1 A schematic representation of a rolling element arrangement of an axial bearing of a first embodiment with a wire cage formed from an endless wire, Fig. 2 a sectional view through a rolling element threaded onto the wire along line II-II in Fig. 1, Fig. 3 a schematic representation of a rolling element arrangement of an axial bearing of a second embodiment with a wire cage formed from individual U-shaped clamps, and Fig. 4 a sectional view through a rolling element threaded onto two wire clamps along line IV-IV in Fig. 3.

[0018] Fig. Figure 1 shows a schematic representation of an axial bearing 1 according to the invention, of which only the rolling element arrangement 2 is shown. The two axial bearing discs, which are usually provided, are not shown for the sake of clarity.

[0019] The rolling element arrangement 2 has a cage 3 made of an endlessly circulating, metallic wire 4, which is a round wire (see Fig. 2). Corresponding rolling elements 5 are threaded onto the wire 4, each with an opening 6, here in the form of a cylindrical bore (see Fig. 2), exhibiting the wire 4 passing through the opening.

[0020] How Fig. As shown in Figure 1, the wire 4 is bent in a meandering shape, forming a multitude of individual loop-shaped retaining sections 7. These sections are U-shaped and each has two straight longitudinal legs 8, each connected to the other by a transverse leg 9. The transverse legs 9 are located radially outside. Radially inside, the individual retaining sections 7 are connected by further transverse legs 10, ultimately resulting in the corresponding meandering shape. Fig. As shown in Figure 1, a rolling element 5, here designed as a needle, is threaded onto every second longitudinal leg 8. This means that, in this variant, every second bearing point formed by a longitudinal leg 8 is ultimately occupied. This allows the individual retaining sections 7 to be bent accordingly tightly. However, it would also be conceivable to bend the retaining sections somewhat further, i.e., to make the transverse legs 9, 10 somewhat longer, so that the longitudinal legs 8 are spaced somewhat further apart and each longitudinal leg 8 can be fitted with a rolling element 5.

[0021] To manufacture the rolling element assembly 2, a simple, straight wire 4 is used as the starting material. A first rolling element 5 is threaded onto this wire, followed by a first U-shaped retaining section. A second rolling element is then threaded onto this retaining section, followed by another retaining section and a third rolling element, etc., until all rolling elements 5 have been threaded. At this stage, the assembly is still straight. This is then, if necessary after cutting the wire 4 to length, transformed into the assembly described in... Fig. 1 bent into the ring shape shown, and then the two free ends of the wire 4 are welded together.

[0022] Fig. Figure 3 shows an axial bearing 1 according to the invention, of which only the rolling element arrangement 2 is shown. The same reference numerals are used for comparable components.

[0023] Here too, a cage 3 is provided, which is formed from a wire 4. However, here the cage 4 is formed from a multitude of individual U-shaped clamps 11, which are also, see Fig. 4, consisting of a round metal wire. Due to their U-shape, the clamps 11 have two straight longitudinal legs 12 and a connecting transverse leg 13, the arrangement being such that the transverse legs 13 are positioned radially outside.

[0024] The rolling elements 5, which here are guided as rollers, also have an opening 6 designed as a cylindrical bore, through which, in this variant, however, two longitudinal legs 12 of two adjacent clamps 11 engage, see Fig.4. The ends 14 of the two longitudinal legs protruding from the opening 6 are each bent over, thereby radially fixing the rolling elements 5 to the longitudinal legs 12. In this variant, each clamp 12 therefore forms a clamp-like retaining section 15 to which the rolling elements 5, which are gripped by the retaining sections 15, are fixed.

[0025] To manufacture this rolling element arrangement 2, the clamps 11, which still have their ends straight, are first prepared and arranged side by side in a row. A rolling element 5 is threaded onto each of the parallel longitudinal legs 12 adjacent to each other. One longitudinal leg of the first clamp 11 and one longitudinal leg of the last clamp 11 remain unused. This arrangement is then bent into a ring shape so that the two unused longitudinal legs of the first and last clamp 11 lie parallel to each other. The last rolling element is then threaded onto this pair of longitudinal legs, and the ring shape is fixed in place. If not already done, all ends 14 are then bent accordingly. Reference symbol list 1 axial bearing 2 rolling element arrangement 3 cage 4-wire 5 rolling elements 6 Breakthrough 7 Stop section 8 longitudinal legs 9 transverse legs 10 crossbars 11 bracket 12 longitudinal legs 13 transverse legs 14 End 15 Stop section

Claims

[1] Axial bearing, comprising an annular rolling element arrangement (2) with several needle- or roller-shaped rolling elements (5) which are guided on a cage (3), characterized by that the rolling elements (5) each have a central opening (6), wherein the annular cage (3) formed from wire (4) has a plurality of loop- or clamp-shaped holding sections (7, 15) which pass through the openings (6). [2] Axial bearing according to claim 1, characterized by that the openings (6) are holes and the wire (4) is a round wire. [3] Axial bearing according to claim 1 or 2, characterized by that the wire (4) forming the cage (3) is endless and runs in a meandering manner, forming loop-shaped holding sections (7) with straight longitudinal legs (8) and a transverse leg (9, 10) connecting these. [4] Axial bearing according to claim 3, characterized by that a rolling element (5) is arranged on each or at least every second longitudinal leg (8). [5] Axial bearing according to claim 1 or 2, characterized by in that the cage (3) is formed by means of a plurality of individual U-shaped clamps (11), each forming a clamp-like holding section (15) and having two straight longitudinal legs (12) and a transverse leg (13) connecting them, wherein each longitudinal leg (12) passes through an opening (6) of a rolling body (5) and wherein each opening (6) is passed through by two longitudinal legs (12) of two adjacent clamps (11). [6] Axial bearing according to claim 5, characterized by that the ends (14) of the longitudinal legs (12) projecting from the openings (6) are bent over. [7] Axial bearing according to claim 5 or 6, characterized by that the U-clamps (11) are arranged such that the transverse legs (13) are positioned radially outwardly on the annular rolling element arrangement (2). [8] Method for producing a rolling element arrangement for an axial bearing (1) according to one of claims 1 to 4, characterized by that individual rolling elements (5), each having a central opening (6), are threaded one after the other onto a straight wire (4), the wire (4) being bent in a meandering manner after each threaded rolling element (5) to form loop-shaped holding sections (7), the wire (4) being bent into a ring shape after the last rolling element (5) has been threaded onto the wire (4) and its ends being connected to one another in a form-fitting manner. [9] Method for producing a rolling element arrangement (2) according to one of claims 1 and 5 to 7, characterized byin that the rolling elements (5), each having an opening (6) passing through its center, are threaded onto the longitudinal legs (12) of individual U-shaped clamps (11) made of wire (4), two longitudinal legs (12) each passing through an opening (6) of a rolling element (5), after the second-to-last rolling element (5) has been threaded on, the arrangement is bent into a ring shape and the two free longitudinal legs (12) of the first and last clamps (11) are guided through the opening (6) of the last rolling element (5), the ends (14) of the longitudinal legs (12) projecting from the openings (6) being bent over during or after threading on.

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