Friction roller-type transmission

Patent metadata

Field	Value
Publication number	US-10309501-B2
Application number	US-201515313167-A
Country	US
Kind code	B2
Filing date	Mar 25, 2015
Priority date	May 23, 2014
Publication date	Jun 4, 2019
Grant date	Jun 4, 2019

Abstract

A sun roller of a friction roller-type transmission includes a movable sun roller element (23) capable of moving in an axial direction. Furthermore, the sun roller is provided with a loading cam mechanism which is formed along the circumferential direction of an input shaft (12), the loading cam mechanism having a first cam surface (75), a second cam surface (77) arranged facing the first cam surface (75) and secured to the input shaft (12), rolling elements (63) held between the first and second cam surfaces (75, 77), and an annular holding device (51), and the loading cam mechanism axially displacing the movable sun roller element (23). The holding device (51) has an inside-diameter-surface guiding part (81) for positioning the holding device relative to the input shaft by being fitted over the input shaft, the guiding part being provided to the inside diameter surface.

First claim

The invention claimed is:

1. A friction roller-type transmission comprising:
an input shaft,
a sun roller disposed concentrically with the input shaft and having a rolling contact surface on an outer peripheral surface thereof,
an annular roller disposed concentrically with the sun roller at an outer periphery-side of the sun roller and having a rolling contact surface on an inner peripheral surface thereof,
a plurality of intermediate rollers supported to be rotatable about an axis of rotation arranged in parallel with the input shaft in an annular space between the rolling contact surface of the sun roller and the rolling contact surface of the annular roller and configured to rolling-contact the outer peripheral surface of the sun roller and an inner peripheral surface of the annular roller, and
an output shaft connected to an axial side surface of the annular roller or to the intermediate rollers,
wherein the sun roller includes a pair of sun roller elements divided in an axial direction of the input shaft, and
wherein at least one of the pair of sun roller elements is a moveable sun roller element configured to be freely moveable in the axial direction,
the friction roller-type transmission further comprising a loading cam mechanism including a first cam surface formed along a circumferential direction of the input shaft and having an axial depth gradually changing in the circumferential direction, a second cam surface disposed to face the first cam surface, a rolling element held between the first and second cam surfaces, and an annular holding device configured to hold the rolling element in a pocket, the loading cam mechanism being configured to rotate any one of the first and second cam surfaces together with the input shaft and to axially displace the moveable sun roller element, and
wherein the holding device comprises an inner diameter surface guiding part provided on an inner diameter surface and configured to be fitted over the input shaft and to thereby position the holding device relative to the input shaft.

2. The friction roller-type transmission according to claim 1 ,
wherein the first cam surface is formed at a plurality of places along the circumferential direction on an outer end surface of the moveable sun roller element, which is opposite to the other sun roller element,
wherein the second cam surface is formed at a plurality of places along the circumferential direction on an end surface of a cam ring, which is disposed to face the outer end surface of the moveable sun roller element via the holding device and configured to rotate together with the input shaft, in correspondence to the first cam surfaces, and
wherein the holding device comprises a plurality of pockets configured to hold a plurality of the rolling elements, respectively.

3. The friction roller-type transmission according to claim 2 ,
wherein the cam ring has a boss part extending toward the moveable sun roller element, and
wherein the inner diameter surface guiding part of the holding device is fitted and inserted to the boss part of the cam ring.

4. The friction roller-type transmission according to claim 2 ,
wherein an end surface guiding part for positioning the holding device on the input shaft in the axial direction and a rotation direction is provided between the end surface of the cam ring and the holding device and between the outer end surface of the moveable sun roller element and the holding device, respectively.

5. The friction roller-type transmission according to claim 4 , wherein the end surface guiding part comprises:
protrusions provided on both end surfaces of the holding device and protruding toward an outside of the holding device along the axial direction, and
guide grooves provided for the moveable sun roller element and the cam ring and configure to guide the protrusions of the holding device to an end surface facing the holding device.

6. The friction roller-type transmission according to claim 5 ,
wherein the guide grooves have an inclination of an axial depth, which is the same as the first cam surface and the second cam surface.

7. The friction roller-type transmission according to claim 5 ,
wherein the holding device has the plurality of pockets disposed at equal intervals along the circumferential direction, and the protrusions are disposed at intermediate positions between the adjacent pockets in the circumferential direction.

Assignees

• Nsk Ltd

Inventors

• Yoshioka Hiroyasu
• Matsuda Yasuyuki
• Tanaka Kazutaka
• Imanishi Takashi

Classifications

• F16H13/04

  with balls or with rollers acting in a similar manner · CPC title

• F16H13/08 Primary

  with balls or with rollers acting in a similar manner · CPC title

• F16H13/10 Primary

  Means for influencing the pressure between the members · CPC title

• F16H25/186

  with reciprocation along the axis of oscillation · CPC title