JP2015137698A - Planetary roller type friction transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily make a sun roller shaft stable and fast with a simple structure.SOLUTION: A planetary roller type friction transmission device has: a plurality of planetary rollers 5 interposed, in a pressure-contact state, between an outer peripheral surface 2a of a sun roller shaft 2 and an inner peripheral surface 6a of an annular outer ring 6; and a carrier shaft 7 which equally divides and supports the planetary rollers 5. Driving force of the carrier shaft can be transmitted to the sun roller shaft through revolution and rotation of the planetary rollers or driving force of the sun roller shaft can be transmitted to the carrier shaft through the revolution and rotation of the planetary rollers. A carrier external-tooth gear 13 is provided at an outer periphery of the carrier shaft on the opposite side from the planetary rollers, and an input or output gear shaft 14 is provided which engages with the carrier external-tooth gear, to pivotally support the sun roller shaft on both sides through the carrier shaft. The planetary rollers are cylindrical, and positioned and held in a rotating direction in a packet 7b of the carrier shaft movably along in axial directions, and flange parts 6b, 6c are provided on both inner peripheral surface sides of the outer ring.

Description

  The present invention relates to a support structure for a sun roller shaft of a planetary roller friction transmission device.

  Conventionally, for example, as shown in Patent Document 1, a plurality of planetary rollers are interposed between an outer peripheral surface of a sun roller shaft and an inner peripheral surface of an annular outer ring, and the planetary rollers are equally divided and supported. A planetary roller type frictional transmission (acceleration or deceleration) device having a carrier shaft is known. When the carrier shaft is the input shaft and the sun roller shaft is the output shaft, the speed increases. Further, when the sun roller shaft is the input shaft and the carrier shaft is the output shaft, it becomes a speed reducer. This planetary roller friction transmission device has a small number of parts, low noise, and high deceleration and speed increase ratios.

  On the other hand, in order to increase the speed increase or reduction ratio, as a combination of a planetary roller friction reducer and a spur gear reducer, in Patent Document 2, a flat roller shaft is provided at the end of the carrier shaft of the planetary roller friction reducer. A combination of a transmission using a multi-stage spur gear that is provided with a gear and meshed with the spur gear is disclosed.

JP 2005-024078 A JP 2001-108038 A

  However, since the planetary roller of Patent Document 2 uses a needle bearing, it has a large number of parts and cannot be reduced in size. Further, in Patent Documents 1 and 2, the sun roller shaft has a cantilever support structure, which is unstable, and there is a problem that it is difficult to further increase the speed when used as a speed increaser.

  In view of such problems, an object of the present invention is to provide a planetary roller friction transmission that can easily increase the speed with a simple structure and can stably support a sun roller shaft.

  In the present invention, a plurality of planetary rollers are interposed in pressure contact between the outer peripheral surface of the sun roller shaft and the inner peripheral surface of the annular outer ring, and the carrier shaft is provided so as to divide and support the planetary roller. The driving force of the carrier shaft is transmitted to the sun roller shaft by the revolving rotation of the planetary roller, or the driving force of the sun roller shaft is transmitted to the carrier shaft by the revolving rotation of the planetary roller. A friction transmission, wherein a carrier external gear is provided on the outer periphery of the carrier shaft on the side opposite to the planetary roller, and an input or output gear shaft that meshes with the carrier external gear is provided. The above-mentioned problems have been solved by providing a planetary roller friction transmission device in which the sun roller shaft is pivotally supported in a dual-supported state.

  That is, a through hole is provided in a carrier shaft having an external gear, the sun roller shaft is penetrated, and the carrier shaft is supported at an outer position of the carrier shaft.

  According to a second aspect of the present invention, the planetary roller has a cylindrical shape, is axially movable in the pocket of the carrier shaft and is positioned and held in the rotational direction, and the inner peripheral surface of the annular outer ring. The hooks were provided on both sides, and the planetary roller was fitted between the hooks to rotate. Thereby, the positioning in the axial direction is performed. Moreover, each part including a roller is reduced in weight.

  In the present invention, the carrier external gear is provided in the carrier, the input / output shaft is arranged by shifting the axis, and the sun roller shaft is supported by supporting the sun roller shaft through the carrier shaft. Further speedup is possible. Also, the structure is simple.

  Further, in the invention described in claim 2, since the axial movement is small and each part including the roller is reduced in weight, the speed can be further increased and the structure is simplified.

1 is a longitudinal sectional view of a planetary roller friction transmission device showing an embodiment of the present invention. It is the sectional view on the AA line of FIG. It is the BB sectional view taken on the line of FIG.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a planetary roller friction transmission device according to the present invention, and FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1, showing a friction roller transmission mechanism. FIG. 3 is a cross-sectional view taken along the line BB of FIG. 1 and shows a spur gear transmission mechanism. As shown in the drawing, in the planetary roller friction transmission device 1, a sun roller shaft 2 serving as an input or output shaft is pivotally supported by bearings 4 a and 4 b provided on the main body 3. Three cylindrical planetary rollers 5 are equally arranged around the outer peripheral surface 2 a of the sun roller shaft 2. Further, an outer ring 6 having an annular inner peripheral surface 6a surrounding the outer periphery 5a of the planetary roller 5 is fixed to the main body 3 with bolts or the like. The outer peripheral surface 2a of the sun roller shaft, the outer peripheral surface 5a of the planetary roller, and the inner peripheral surface 6a of the outer ring are configured to rotate and rotate with each other in a pressure contact state.

  A carrier shaft 7 for equally dividing and supporting the three planetary rollers 5 is provided. The carrier shaft 7 is provided with three pockets 7b each including a notched concave surface 7a penetrating in the axial direction. The notched concave surface 7a of the pocket 7b has substantially the same diameter as the outer periphery 5a of the planetary roller, and has a minute gap. The planetary roller 5 slides (rotates) in the pocket 7b. The carrier shaft 7 is rotatably supported by bearings 4c and 4c provided on the main body 3. Further, the snap rings 8a, 8b and the like provided on both sides of the bearing 4c are prevented from moving in the axial direction.

  On both sides of the inner peripheral surface 6a of the outer ring 6, flanges 6b and 6c extending in the axial direction are provided. Further, both ends of the planetary roller 5 in the axial direction are fitted between the flange portions 6b and 6c with a minute gap to restrict the axial movement of the planetary roller. The driving force of the carrier shaft 7 can be transmitted to the sun roller shaft 2 by revolving rotation of the planetary roller 5, and the driving force of the sun roller shaft can be transmitted to the carrier shaft by revolving rotation of the planetary roller. Such an operation is the same as the conventional one, and a detailed description thereof is omitted.

  A gear transmission (acceleration) portion is provided in the front stage of the carrier shaft 7 according to the embodiment of the present invention. A carrier external gear 13 is provided on the outer periphery of the carrier shaft 7 on the anti-planetary roller (left side in FIG. 3) side. Further, the carrier external gear 13 is provided with an input or output gear shaft 14 having a spur gear 14a having a large number of meshing teeth so that the rotation of the input or output gear shaft can be further increased or decreased. The input or output shaft 14 is rotatably supported on the main body 3 by bearings 17 and 17. A rotational force is transmitted to the input or output shaft 14 from a driving unit (not shown) or a multistage transmission.

  A through hole 15 is provided in the carrier shaft 7. The counter-output (left side in FIG. 1) side of the sun roller shaft 2 extends through the through hole 15 and is pivotally supported by the main body 3 via bearings 4a and 4b. The sun roller shaft 2 is supported at both ends by a bearing 4a and a bearing 4b. As a result, the number of speed increasing stages is increased while the sun roller shaft 2 is stabilized, and the speed can be increased or decreased. Although the speed increase or reduction ratio in the previous stage is one stage, it goes without saying that it may be two or more stages.

DESCRIPTION OF SYMBOLS 1 Planetary roller type differential frictional transmission device 2 Sun roller shaft 2a Sun roller shaft outer periphery 4a, 4b Bearing 5 Planet roller 5a Planet roller outer periphery 6 Outer ring 6a Outer ring inner peripheral surface 6b, 6c Ridge part 7 Carrier shaft 7b Carrier shaft Pocket 13 Carrier external gear 14 Input or output gear shaft

Claims (2)

A plurality of planetary rollers interposed between the outer peripheral surface of the sun roller shaft and the inner peripheral surface of the annular outer ring, and a carrier shaft for equally dividing and supporting the planetary roller, and the carrier shaft Is transmitted to the sun roller shaft by revolving rotation of the planetary roller, or the driving force of the sun roller shaft is transmitted to the carrier shaft by revolving rotation of the planetary roller. And
A carrier external gear is provided on the outer periphery of the carrier shaft on the side of the anti-planetary roller, an input or output gear shaft that meshes with the carrier external gear is provided, and the sun roller shaft is in a dual-supported state through the carrier shaft A planetary roller friction transmission device characterized by being supported by a shaft.   The planetary roller has a cylindrical shape, is axially movable in the pocket of the carrier shaft, is positioned and held in the rotational direction, and has flanges on both inner peripheral surfaces of the annular outer ring. The planetary roller friction transmission device according to claim 1, wherein the planetary roller friction transmission device is configured to be fitted and rotated between the flange portions.

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