Transmission

Patent metadata

Field	Value
Publication number	US-11035420-B2
Application number	US-201916368050-A
Country	US
Kind code	B2
Filing date	Mar 28, 2019
Priority date	Mar 30, 2018
Publication date	Jun 15, 2021
Grant date	Jun 15, 2021

Abstract

The transmission includes a rotation shaft, a shift gear, and a gear switching part. The shift gear is rotatably supported by the rotation shaft. The gear switching part is relatively unrotatably supported by the rotation shaft in a movable manner in an axial direction. The gear switching part is configured to be moved in the axial direction by a shift fork, to switch connection and disconnection between the rotation shaft and the shift gear. The gear switching part and the shift fork have a bearing therebetween. The bearing is brought into contact with the gear switching part and the shift fork, thereby reducing friction between the gear switching part and the shift fork, resulting in improvement of durability of the sliding surfaces of the gear switching part and the shift fork.

First claim

What is claimed is:

1. A transmission comprising:
a rotation shaft;
a shift gear rotatably supported by the rotation shaft; and
a gear switching part relatively unrotatably supported by the rotation shaft in a movable manner in an axial direction, the gear switching part configured to be moved in the axial direction by a shift fork to switch connection and disconnection between the rotation shaft and the shift gear,
wherein a bearing is disposed between the shift fork and the gear switching part in contact with the shift fork and the gear switching part, the bearing comprising:
a first inner bearing member and a first outer bearing member disposed in rotatable relation between the shift fork and the gear switching part on a first side of the shift fork, and
a second inner bearing member and a second outer bearing member disposed in rotatable relation between the shift fork and the gear switching part on a second side of the shift fork,
wherein the first and second inner bearing members comprise washers, and wherein the first and second outer bearing members comprise washers.

2. The transmission according to claim 1 , further comprising a synchronizer that includes:
a hub relatively unrotatably supported by the rotation shaft while movement in the axial direction is inhibited;
a sleeve supported by the hub in a movable manner in the axial direction while relative rotation is inhibited; and
a blocking ring disposed between the shift gear and the sleeve, the shift gear having gear dog teeth,
the blocking ring having ring teeth that are disposed between sleeve teeth of the sleeve and the gear dog teeth,
wherein the sleeve is configured to move to make an inner circumferential surface of the blocking ring come into contact with a protruding cylindrical part of the shift gear, whereby the sleeve synchronizes with the shift gear,
wherein the gear switching part uses the sleeve, and
wherein the connection and the disconnection between the rotation shaft and the shift gear are switched by connecting and disconnecting the sleeve teeth of the sleeve to and from the gear dog teeth of the shift gear.

3. The transmission according to claim 2 , wherein the bearing is disposed between a thrust surface of the shift fork and a thrust surface of the sleeve,
the bearing includes a shift fork-side contact member and a sleeve-side contact member that are relatively rotatable, the shift fork-side contact member comprises the first outer bearing member and is brought into contact with the shift fork, and the sleeve-side contact member comprises the first inner bearing member and is brought into contact with the sleeve.

4. The transmission according to claim 2 , wherein the sleeve has at least one open end in the axial direction.

5. The transmission according to claim 3 , wherein the shift fork includes a recessed groove that opens to the sleeve,
the sleeve includes a protrusion that protrudes in a radial direction to be inserted into the recessed groove, and
the bearing is disposed between a thrust surface of the protrusion of the sleeve and a thrust surface of the recessed groove.

6. The transmission according to claim 3 , wherein the sleeve includes a rim that protrudes in a radial direction at an end other than the open end,
a first bearing is disposed in contact with the rim,
a second bearing is disposed on a side opposite to the first bearing across the shift fork in the axial direction, and
a retainer is disposed on a side opposite to the shift fork across the second bearing in the axial direction to inhibit the second bearing from moving in the axial direction away from the shift fork.

7. A transmission according to claim 2 ,
wherein the bearing is disposed between a radial surface of the shift fork and a radial surface of the sleeve, and the bearing includes a shift fork-side contact member, which is brought into contact with the shift fork, and a sleeve-side contact member, which is brought into contact with the sleeve, and
wherein the shift fork-side contact member and the sleeve-side contact member are relatively rotatable.

8. The transmission according to claim 7 , wherein the shift fork includes a fork-side recessed groove that opens to the sleeve,
the sleeve includes a raised part that protrudes in a radial direction and retainers that are disposed at positions separated from the raised part in the axial direction,
the shift fork-side contact member is fitted into the fork-side recessed groove, and
the sleeve-side contact member is held by the raised part and the retainers.

9. The transmission according to claim 2 , wherein the sleeve and the hub are disposed between shift gears in the axial direction,
protruding cylindrical parts of the shift gears extend toward the hub, and
when the sleeve is at a neutral position, the bearing is disposed at a position which is further outward, in the axial direction, than an inner end of a corresponding one of the protruding cylindrical parts.

10. The transmission according to claim 3 , wherein the sleeve has at least one open end in the axial direction.

11. The transmission according to claim 4 , wherein the shift fork includes a recessed groove that opens to the sleeve,
the sleeve includes a protrusion that protrudes in a radial direction to be inserted into the recessed groove, and
the bearing is disposed between a thrust surface of the protrusion of the sleeve and a thrust surface of the recessed groove.

12. The transmission according to claim 10 , wherein the sleeve includes a rim that protrudes in a radial direction at an end other than the open end,
a first bearing is disposed in contact with the rim,
a second bearing is disposed on a side opposite to the first bearing across the shift fork in the axial direction, and
a retainer is disposed on a side opposite to the shift fork across the second bearing in the axial direction to inhibit the second bearing from moving in the axial direction away from the shift fork.

13. The transmission according to claim 3 , wherein the sleeve and the hub are disposed between shift gears in the axial direction,
protruding cylindrical parts of the shift gears extend toward the hub, and
when the sleeve is at a neutral position, the bearing is disposed at a position which is further outward, in the axial direction, than an inner end of a corresponding one of the protruding cylindrical parts.

14. The transmission according to claim 4 , wherein the sleeve and the hub are disposed between shift gears in the axial direction,
protruding cylindrical parts of the shift gears extend toward the hub, and
when the sleeve is at a neutral position, the bearing is disposed at a position which is further outward, in the axial direction, than an inner end of a corresponding one of the protruding cylindrical parts.

15. A transmission comprising:
a rotation shaft;
a shift gear rotatably supported by the rotation shaft; and
a gear switching part relatively unrotatably supported by the rotation shaft in a movable manner in an axial direction, the gear switching part configured to be moved in the axial direction by a shift fork to switch connection and disconnection between the rotation shaft and the shift gear,
wherein a bearing is disposed between the shift fork and the gear switching part in contact with the shift fork and the gear switching part, the bearing comprising:
a first inner bearing member and a first outer bearing member disposed in rotatable relation between the shift fork and the gear switching part on a first side of the shift fork, and
a second inner bearing member and a second outer bearing me

Assignees

• Honda Motor Co Ltd

Inventors

• Adachi Jun

Classifications

• F16D23/08 Primary

  with a blocking mechanism that only releases the clutching member on synchronisation (in combination with an additional friction clutch F16D23/06) · CPC title

• F16D2011/002

  using an external and axially slidable sleeve for coupling the teeth of both coupling components together · CPC title

• F16D23/06

  and a blocking mechanism preventing the engagement of the main clutch prior to synchronisation · CPC title

• B60Y2200/12

  Motorcycles, Trikes; Quads; Scooters · CPC title

• F16H3/093

  with two or more countershafts · CPC title