WO2015014355A1

WO2015014355A1 - Split rolling body cage made from plastic

Info

Publication number: WO2015014355A1
Application number: PCT/DE2014/200285
Authority: WO
Inventors: Franz Huschka; Peter Solfrank; Tobias Mederer
Original assignee: Schaeffler Technologies Gmbh & Co. Kg
Priority date: 2013-08-02
Filing date: 2014-06-30
Publication date: 2015-02-05
Also published as: DE102013215204A1

Abstract

The invention relates to a split rolling body cage (1) made from plastic, consisting of two guide rims (2) which are connected via webs (3) with the formation of individual pockets (4) which receive in each case one rolling body, wherein the cage is slotted axially at at least one circumferential point with the formation of a joint, wherein at least one recess is formed at a cage end which adjoins the joint and at least one corresponding engagement projection which engages into the recess in the mounted position is formed at the other cage end. According to the invention, radial projections (10a, 10b) which extend in the circumferential direction are provided on the guide rims on the outer side or the inner side at least in the region of the pocket which is adjacent to the engagement projection or the recess.

Description

Name of the invention

Split rolling element cage made of plastic Description

Field of the invention

The invention relates to a divided Wälzkörperkäfig made of plastic, consisting of two Seitenborden, which are connected to form individual, each having a rolling body receiving pockets via webs, wherein the cage is slit axially at least one circumferential point to form a parting line, wherein at one At least one recess is formed adjacent to the parting line and at least one corresponding engagement protrusion is formed on the other cage end and engages in the recess in the assembly position.

BACKGROUND OF THE INVENTION A rolling element cage serves to receive or retain the rolling bodies, for example needles, for which purpose corresponding pockets are formed on the cage into which the rolling bodies are inserted. Known Wälzkörperkäfige can also be performed divided, so be provided with an axially extending slot, so that forms a parting line. That is, the rolling element cage is ultimately movable in the circumferential direction. However, in order to fix it in the assembly position in a defined form, it is known to provide corresponding connecting means on the cages near the parting lines, which are often also called a cage lock. For this purpose, a recess is formed on a cage end and a corresponding engagement projection is formed on the other end, which engage in one another in the assembly position. The geometry of the engagement projection as well as the recess is chosen so that a stable connection results, for example in the manner of a dovetail profile. If necessary, the connection also allows a certain axial mobility as well as a certain mobility in the circumferential direction. Since the Wälzkörperkäfig is made of plastic, it is therefore sufficiently elastic, which allows easy closing of the separation point, so connecting the cage ends by mating.

Although the connecting elements make it possible to fix the cage ends, problems can arise if loads or accelerations act on the plastic cage during operation, ie if the components rotatably mounted relative to one another via the fitted rolling element cage rotate. Unintentional opening can also occur during transport or during assembly of the already equipped Wälzkörperkäfigs, so the bearing itself, that is, this already has an inner ring or an outer ring, come when the Wälzkörperkäfig this is exposed to corresponding accelerations or forces. Because due to the inherent elasticity in the region of the connecting elements or of the cage lock, a torsional load can occur, that is to say that the cage ends rotate or twist relative to one another, which in turn can lead to unintentional opening of the rolling element cage, that is to say of the needle ring. At any given time, this inevitably leads to problems. Because opens a populated, mounted Wälzkörperkäfig during operation, this can lead to significant damage to the stored components respectively the component containing these components, so for example a motor when the Wälzkörperkäfig respectively the populated Wälzkörperkranz for example the storage of a balancer shaft or Similar serve. If an open or incorrectly closed cage is installed, it may be damaged during operation.

OBJECT OF THE INVENTION The invention is thus based on the object of conceiving a split rolling element cage, which in contrast is improved and in which unintentional opening in the installed state or in operation is precluded. Description of the invention

To achieve this object, it is provided according to the invention in a split Wälzkörperkäfig of the type mentioned that provided on the Führungsborden at least in the region of each of the engagement projection or the recess adjacent pocket on the outside or inside radial, circumferentially extending projections are.

When Wälzkörperkäfig invention corresponding protrusions are provided at least on one side of the guide rims, in the region of the first pocket following the respective lock side, which protrude in the radial direction of the respective guide board. These projections act on the one hand stiffening, in particular, if they extend a bit far around the perimeter, so are elongated. However, they act in a path-limiting manner, that is to say that any torsional movement is limited by the fact that the projection (s) abuts adjacent components, for example an outer ring which engages around the rolling-element cage or the roller bearing and on which they are located in the pockets Rolling rolling elements, when the projections are arranged on the outside. In the case of an arrangement on the inside, the projections would, for example, abut the torsion on the outer surface of the shaft on which the rolling elements roll.

As a result of these projections, the torsional or twisting motion is therefore limited or, depending on how high the corresponding projections are selected, as far as possible prevented, unintentional opening of the cage lock resulting from such movement is therefore excluded , The properly assembled roller cage thus remains in its closed position even when loaded during operation.

Preferably, the projections are provided both on the outside and on the inside. This is useful so as to ensure a travel limit in each direction, usually after the guide rims, Seen radially, are substantially centered between the two pitch circles of the assembled rolling elements.

The projections extend expediently at least a little way in the circumferential direction, so they are elongated. Preferably, they extend at least over the length of the respective first pocket in the circumferential direction, so that a sufficiently long support distance is given. With sufficient strength, the projections can also be made shorter. The outside of the projections should be bent, according to the shape of the surface on which it should strike, in order to realize the largest possible contact surface.

The radial height of the projections, whether they are now provided on the outside, the inside or on both sides, is preferably dimensioned such that their minimum distance to the outer or inner pitch circle of the recorded rolling elements is 0.01 mm. This means that they are almost as close as possible in the direction of the component to which they should strike in the event of torsional stress, so therefore only a very narrow gap between the abutment surfaces of the projections and this component, be it outer ring, be it shaft etc. remains. The narrower the gap, the lower the possible torsional motion. Of course, the final realized gap size or the distance also depends on the size of the rolling element cage. For cages with small diameters in the range of a few centimeters, such small gaps are preferred, in contrast to significantly larger Wälzkörperkäfigen the gap may also be slightly larger, for example in the range of 0.1 mm or 1 mm or the like.

The individual projections themselves may be narrower than the guide rims, but they may also have the same width. The specific width of the margin should be selected accordingly with regard to sufficient stability. Since the Wälzkörperkäfig is made of plastic, the one-piece design of the projections, which are integrally formed on the guide rims, is particularly simple. The Wälzkörperkäfig is produced by injection molding, so that the projections injection molding technology can be formed accordingly, even with the sufficient shape and size accuracy.

The projection and the recess itself preferably form a dovetail connection in the closed state. You can, for example, have two opposing axial end faces, which, viewed in the circumferential direction, obliquely and substantially parallel to each other, such that the cage ends in the mounting position are limited axially and circumferentially movable. Even such an inherent mobility of the cage lock does not lead to an unwanted opening, since the torsion movement as described is largely or almost completely prevented via the projections.

In addition to the Wälzkörperkäfig the invention further relates to a rolling bearing comprising a Wälzkörperkäfig the described embodiment, as well as received in its pockets rolling elements. These rolling elements may be needles or cylindrical rollers or the like. Depending on the application, the rolling bearing may also have an outer ring and / or an inner ring.

Short description of the drawing

A preferred embodiment of the invention is illustrated in the accompanying drawings and will be described in more detail below. 1 shows a plan view of a rolling element cage according to the invention, FIG. 2 shows a side view of the cage from FIG. 1, and FIG Figure 3 is a schematic diagram of a mounted rolling bearing with a Wälzkörperkäfig invention.

DETAILED DESCRIPTION OF THE DRAWING FIG. 1 shows a rolling element cage 1 made of plastic according to the invention, for example PA4.6 or PA6.6, it being understood that it is also possible to use other plastic materials for cage production.

The rolling element cage 1 comprises two guide rims 2, which are connected to one another via a plurality of individual webs 3, wherein a pocket 4 is formed between each two webs 3. This is, as will be discussed below in connection with Figure 3, the recording of each rolling element, such as a needle or a roller. The rolling element cage 1 has a parting line 5, which runs in the axial direction, and along which the rolling element cage 1 can be opened. In the area of the resulting cage ends 6, 7 connecting means, which form a cage lock, are provided. At the cage end 6, a receptacle 8 is provided in the example shown, while an engagement projection 9 is provided on the cage end 7, which engages in the mounting position, as Figure 2, in the receptacle 8. By way of example, a latching connection is shown, of course, other forms of the recess 8 and the engagement projection 9 are conceivable as long as a sufficient connection of the two cage ends 6, 7 is possible. The recesses and the engagement projection preferably form a dovetail connection.

As shown in FIGS. 1 and 2, radially extending protrusions are provided on both guide rims 2 on both the inside and the outside, in the case of the arrangement on the outside, the protrusions 10a, in the case of the inside, the protrusions 10b. At the respective outer side or inner side of the respective guide board, in the circumferential direction, two such projections 10a and 10b respectively are provided, as FIGS. 1 and 2 show. The respective projections 10a, 10b are in the range They are elongated, as the figures show, and preferably extend substantially along the respective pocket length, as can be seen from FIG 2 results.

The width of the respective projection 10a, 10b substantially corresponds to the width of the respective guide board 2. They likewise have a curved-shaped annular surface corresponding to the ring shape of the respective guide board 2, ie each lying on a corresponding radius around the ring center.

Since the rolling element cage 1 is made of plastic, it is readily possible to form the projections 10a, 10b in the desired shape on the guide rims 2. They serve to stiffen and in particular support the cage ends against adjacent third-party objects in the assembly position. Such an assembly example is shown by way of example in FIG.

Figure 3 shows an inventive rolling bearing 1 1 comprising a Wälzkörperkäfig 1 of the type described above, the pockets 4 is each equipped with a rolling element 12 here in the form of a roll or needle. The rolling bearing

1 1 is in the example shown on a shaft 13, in the example shown, a balance shaft for an internal combustion engine, arranged, wherein the rolling elements 12 roll on the lateral surface 14 of the shaft 13. The rolling bearing 1 1 further comprises an outer ring 15, on which the rolling elements

12 roll on the outside. About this outer ring 15, the roller bearing 1 1 is added to a corresponding housing member or the like.

On the rolling element cage 1, the corresponding projections 10a, 10b are provided. Their radial height is dimensioned so that they or their curved outer or end surfaces with very little clearance to the lateral surface 14 in the case of the projections 10b respectively to the lateral surface 16 of the outer ring 15 in the case of the projections 10a. The game respectively the distance should be as possible be small, minimal it should be 0.01 mm. Depending on the size of the rolling bearing but the distance can also be quite a bit larger, as long as this is the Abstützfunktion to prevent a torsional movement is still ensured.

Due to the small clearance between the projections 10a, 10b and the corresponding lateral surfaces 14, 16, the projections 10a, 10b encounter in the event of a torsional load, so if the two cage ends 6 and 7 would rotate relative to each other, immediately against the corresponding lateral surfaces 14 and 16, about which a possible torsion is limited or is almost completely suppressed in view of the small game. Since the two cage ends 6, 7 can not rotate relative to one another, consequently, an undesired opening of the roller body cage resulting therefrom can not occur during operation. Since the projections 10a, 10b extend over a certain length in the circumferential direction, preferably at least over the length of the respectively adjacent pocket, and also a shape compatibility with the lateral surfaces 14, 16, there is also a sufficiently large support length, so that even slightly higher forces can be safely supported and the cage does not open.

Although in the illustrated embodiment, corresponding projections 10a, 10b are provided both on the inside and on the outside, it would be conceivable, in principle, also to provide corresponding projections only on the inside or on the outside. Because even by the one-sided arrangement of such projections, the torsion of the cage ends 6, 7 is limited at least to some extent, so that the cage ends 6, 7 can not twist too far and this possible residual torsion is not sufficient to open the cage lock. LIST OF REFERENCE NUMBERS

Rolling Element

management board

web

bag

parting line

cage end

admission

engaging projection

a lead

b lead

roller bearing

rolling elements

wave

lateral surface

outer ring

lateral surface

Claims

claims

1 . Divided Wälzkörperkäfig plastic, consisting of two side rims, which are connected to form individual rolling elements receiving pockets via webs, wherein the cage is slotted axially at least one circumferential point to form a parting line, wherein at a subsequent to the parting line cage end at least one recess and at least one corresponding engagement projection is formed on the other cage end, which engages in the recess in the assembly position, characterized in that at the guide rims (2) at least in the region of the pocket (9) or the recess (8) adjacent to each 4) are provided on the outside or the inside radial, circumferentially extending projections (10a, 10b).

2. Wälzkörperkäfig according to claim 1, characterized in that the projections (10 a, 10 b) are provided both on the outside and on the inside.

3. rolling element cage according to claim 1 or 2, characterized in that the projections (10 a, 10 b) at least over the length of the pocket (4) extend in the circumferential direction.

4. rolling element cage according to one of the preceding claims, character- ized in that the outer surfaces of the projections (10 a, 10 b) have a curved shape.

5. rolling element cage according to one of the preceding claims, characterized in that the projections (10a, 10b) are dimensioned in their radial height that their minimum distance to the outer or inner pitch circle of the recorded rolling elements is 0.01 mm. Rolling element cage according to one of the preceding claims, characterized in that the projections (10a, 10b) are narrower than the guide rims (2), or in that the projections (10a, 10b) have the same width as the guide rims (2).

Rolling element cage according to one of the preceding claims, characterized in that the projection (9) and the recess (8) enter into a dovetail connection in the closed state.

Rolling bearing, comprising a Wälzkörperkäfig (1) according to one of the preceding claims, as well as in its pockets (4) received rolling elements (12).