FREEWHEELING ELEMENT

Abstract

The invention relates to a freewheeling element comprising a cage, a plurality of clamping bodies, each of the clamping bodies being received in an associated clamping body pocket formed in the cage, and a plurality of rolling bodies, each of the rolling bodies being received in an associated rolling body pocket formed in the cage, the cage having a higher resilience than the clamping bodies and the rolling bodies.

Claims

1. A freewheeling element having: a cage, a plurality of sprags, wherein each of the sprags is accommodated in a respective sprag pocket formed in the cage, and a plurality of rolling bodies, wherein each of the rolling bodies is accommodated in a respective rolling-body pocket, formed in the cage, wherein the cage has a higher level of elasticity than the sprags and the rolling bodies.

2. The freewheeling element of claim 1, wherein the rolling-body pockets are distributed in an equidistant manner along a circumference of the cage.

3. The freewheeling element of claim 1, the respective rolling-body pockets consisting of an odd number of rolling-body pockets.

4. The freewheeling element of claim 3, wherein exactly three, five or seven rolling-body pockets are formed.

5. The freewheeling element of claim 1, wherein a plurality of sprag pockets are formed, between adjacent rolling-body pockets, along a circumference of the cage.

6. The freewheeling element of claim 2, wherein the rolling bodies are accommodated in the rolling-body pockets in a form-fitting manner.

7. The freewheeling element of claim 1, wherein the sprags are accommodated in the sprag pockets in a form-fitting manner.

8. The freewheeling element of claim 1, wherein the cage consists of a polymer material.

9. The freewheeling element of claim 8, wherein the polymer material contains fillers.

10. The freewheeling element of claim 1, wherein the cage consists of a glass-fiber-reinforced polyamide.

11. The freewheeling element as claimed in claim 2, wherein the rolling bodies are accommodated in the rolling-body pockets in a latching or snap-fit connection.

12. The freewheeling element of claim 1, wherein the sprags are accommodated in the sprag pockets in a latching or snap-fit connection.

13. The freewheeling element of claim 1, wherein the cage consists of a polyamide.

14. The freewheeling element of claim 8, wherein the polymer material contains fillers, specifically fibers and/or balls.

15. The freewheeling element as of claim 1, wherein the cage consists of a glass-fiber-reinforced polyamide, specifically PA 66 GF 25.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The invention is explained further with reference to an exemplary embodiment in the figures, in which:

[0015] FIG. 1 shows a perspective view of a freewheeling element;

[0016] FIG. 2 shows a front view of the freewheeling element from FIG. 1;

[0017] FIG. 3 shows a side view of the freewheeling element from FIG. 2;

[0018] FIG. 4 shows a sectional view taken along section plane A-A from FIG. 3; and

[0019] FIG. 5 shows an example of an installed state of the freewheeling element illustrated in FIG. 4.

DETAILED DESCRIPTION

[0020] The freewheeling element 1 illustrated in the figures is of essentially annular design and has a cage 10 made of a polymer material (e.g. polyamide 66 with a 25% glass-fiber fraction). A plurality of sprag pockets 11 and a total of three rolling-body pockets 12 are formed in the cage 10. For reasons of clarity, not all the elements which appear a number of times are provided with a separate reference sign in the figures. Thus, for example, just one sprag pocket 11 is provided with a reference sign in FIG. 4. The sprag pockets 11 and the rolling-body pockets 12 here constitute apertures and/or holes in the cage 10. In other words, the cage 10 has axially running first and second crosspieces 13 and 14 and also annular terminating flanges 15, 16. The spatial volume between in each case two adjacent crosspieces 13, 14 and the two terminating flanges 15, 16 forms in each case a sprag pocket 11 and a rolling-body pocket 12. The crosspieces 13 are each essentially cuboidal and have a convex cross section in the axial direction of the freewheeling element 1. In each case a plurality of sprag pockets 11 are arranged, between two rolling-body pockets 12, in the circumferential direction of the freewheeling element.

[0021] A respective sprag 20 is accommodated in each of the sprag pockets 11. The connection between the sprag 20 and cage 10 here is designed in the form of a snap-fit connection. The sprags 20 are produced from a steel material.

[0022] A respective rolling body 30 is accommodated in each of the rolling-body pockets 12, wherein the rolling body 30 is designed in the form of a cylindrical roller and is produced from a steel material. The connection between the rolling body 30 and cage 10 here is likewise designed in the form of a snap-fit connection. The rolling-body pocket 12 here is embodied such that it encloses or surrounds the rolling bodies 30 from two sides (overlap), and therefore the roller-form rolling body 30 is retained in the cage 10. At the same time, the amount of overlap is selected to be small enough for the elastic property of the cage material coupled with simple manual force to be sufficient to allow the rolling-body pocket to be expanded elastically in order for the rolling body 30 to be clicked/snap-fitted into the rolling-body pocket 12.

[0023] The rolling-body pockets 12 are designed to be wider in the circumferential direction than the sprag pockets 11. In other words, the first crosspieces 13 are at a smaller distance from one another than the second crosspieces 14.

[0024] The level of elasticity of the cage 10—in particular the level of elasticity of the crosspieces 13, 14—is higher than the level of elasticity of the sprags 20 and the rolling bodies 30. This higher level of elasticity of the crosspieces 13, 14 is achieved, in particular, by the cage 10 (or at least the crosspieces 13, 14) being produced from a material which has a higher modulus of elasticity than the materials from which the sprags 20 and the rolling bodies 30 are produced.

[0025] FIG. 5 shows an example of the freewheeling element 1 being installed in a gap 40 between an inner, first (fully) cylindrical component 50 and an outer, second hollow-cylindrical component 60. The dimensions and the shape of the components 50 and 60 here should be considered to be purely illustrative. The first component 50 is arranged coaxially in relation to the second component 60. The freewheeling element 1 is arranged within said gap 40. In a clamping position, the sprags 20 form a frictionally fitting connection with the first component 50 and the second component 60. In a freewheeling position, in contrast, the sprags 20 allow the first component 50 to rotate relative to the second component 60. Each of the crosspieces 13 has a spring-loading surface. In the freewheeling position, the adjacent sprag 20 is in contact with this spring-loading surface. More precisely, in the freewheeling position, surface-area contact and/or an overlap forms between the spring-loading surface of the crosspiece 13 and the adjacent sprag 20. In the clamping position, in contrast, the sprag 20 is not in contact with the spring-loading surface of the crosspiece 13.

[0026] Both in the clamping position and in the freewheeling position, the rolling bodies 30 are in contact with the first component 50 and the second component 60 and provide for low-friction mounting of the two components 50 and 60. In this way, the freewheeling element 1 has a high load-bearing capacity and, at the same time, can serve as a direction-dependent clutch.

[0027] The freewheeling element 1 illustrated in the figures therefore has a cage 10, a plurality of sprags 20, and a plurality of rolling bodies 30. The sprags 20 and the rolling bodies 30 are accommodated in the sprag pocket 11 and the rolling-body pocket 12, respectively, by means of latching or snap-fit connections. The cage 10 has a higher level of elasticity than the sprags 20 and the rolling bodies 30. The total of three rolling-body pockets 12 are distributed in an equidistant manner over the circumference of the cage 10.