Friction transmission

Abstract

To provide a friction transmission device capable of further improving a service life.SOLUTION: A friction transmission device 100 comprises: an input bearing ring 14; a planetary rolling element 20 that is arranged around a rotational axial line of the input bearing ring 14, and is in contact with the input bearing ring 14; an output bearing ring 30 that is in contact with the planetary rolling element 20, and is connected to the output member 32; a first support bearing ring 26 and a second support bearing ring 28 that are in contact with the planetary rolling element 20. The friction transmission device has the plurality of planetary rolling elements 20, and a holder 21 that restricts movement of the plurality of planetary rolling elements 20 in a circumferential direction.SELECTED DRAWING: Figure 2

Claims

1. A friction transmission device comprising: an input raceway; planetary rolling elements arranged around the rotation axis of the input raceway and in contact with the input raceway; an output raceway that is in contact with the planetary rolling elements and connected to an output member; and a first support raceway and a second support raceway that are in contact with the planetary rolling elements, The device has a plurality of the aforementioned planetary rolling elements and a retainer that restricts the circumferential movement of the plurality of planetary rolling elements. The retainer includes a plurality of columnar sections arranged between the plurality of planetary rolling elements, and two ring sections connected to each end of the plurality of columnar sections. A friction transmission device in which, in the axial direction, the total length of the retainer is less than or equal to the total length of the planetary rolling elements.

2. The friction transmission device according to claim 1, wherein the distance between the two ring portions in the axial direction is less than 85% of the total length of the planetary rolling element.

3. The friction transmission device according to claim 1 or 2, wherein the ring portion is in contact with the surfaces of the planetary rolling element that are opposite to the second support raceway and the output raceway.

4. The friction transmission device according to any one of claims 1 to 3, wherein the column portion is in contact with the outermost periphery of the planetary rolling element.

5. A friction transmission device comprising: an input raceway; planetary rolling elements arranged around the rotation axis of the input raceway and in contact with the input raceway; an output raceway that is in contact with the planetary rolling elements and connected to an output member; and a first support raceway and a second support raceway that are in contact with the planetary rolling elements, The device has a plurality of the aforementioned planetary rolling elements and a retainer that restricts the circumferential movement of the plurality of planetary rolling elements. The retainer includes a plurality of columnar sections arranged between the plurality of planetary rolling elements, and two ring sections connected to each end of the plurality of columnar sections. At least a portion of the column is located radially outward from the central axis of the planetary rolling element, A friction transmission device having a plurality of protrusions projecting radially outward from the ring portion, the column portion being connected to the protrusions.

6. The friction transmission device according to claim 5, wherein in the radial direction of the rotation axis, the width of the column portion is greater than the width of the ring portion.

7. The friction transmission device according to claim 5 or 6, wherein the protruding portion is formed to be thicker in the circumferential direction than the column portion and does not come into contact with the planetary rolling element.

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