Traction drive type continuously varible transmission

• US 20060223667A1
• Filed: 02/04/2004
• Published: 10/05/2006
• Est. Priority Date: 02/10/2003
• Status: Active Grant

• Current Assignee: NTN Corporation
• Original Assignee: NTN Corporation
• Inventors: Nakazeki, Tsugito
• Granted Patent: US 7,780,569 B2
• Time in Patent Office: Days
• US Class Current: 476/42
• CPC Class Codes: F16H 15/22 the axes of the members being parallel or approximately parallel
• CPC Class Codes: F16H 37/021 toothed gearing combined with continuous variable friction gearing
• CPC Class Codes: F16H 55/56 of which the bearing parts are relatively axially adjustable

Abstract

A traction drive type continuously variable transmission, comprising a first input/output shaft (6) rotatably supported on a casing (10), a second input/output shaft (7) rotatably supported on the casing (10), a V-pulley (4) supported on the first input/output shaft (6) and having a pair of pulley members forming a V-groove with variable grove width, a ring (3) engaged with the V-pulley (4) and supported at the outer periphery thereof, and a mechanism for moving the ring (3) to the periphery of the second input/output shaft (7).

Claims

1. A traction drive type continuously variable transmission characterized by comprising

a first input/output shaft rotatably supported by a casing,

a second input/output shaft rotatably supported by the casing,

a V-pulley consisting of a pair of pulley members supported by the first input/output shaft and forming a V-shaped groove whose groove width is variable,

a ring engaging the V-pulley and supported at the outer periphery, and

a mechanism for moving the ring around the second input/output shaft.

2. A traction drive type continuously variable transmission as set forth in claim 1, characterized in that said mechanism for moving said ring includes an arm supported turnably around said second input/output shaft, and at least three guide rollers disposed around the outer periphery of said ring, the guide rollers being rotatably supported by the arm.

3. A traction drive type continuously variable transmission as set forth in claim 2, characterized by including a gear fixed to the second input/output shaft, said ring having teeth meshing with the teeth of said gear and also having a smooth cylindrical guide surface, said ring being contacted at said guide surface with the guide rollers.

4. A traction drive type continuously variable transmission as set forth in claim 1, characterized in that said guide rollers are in rolling contact with said ring.

5. A traction drive type continuously variable transmission as set forth in claim 1, characterized in that said guide rollers are in slide contact with said ring.

6. A traction drive type continuously variable transmission as set forth in claim 1, characterized in that the change of the groove width of the V-pulley is operatively associated with the movement of said ring.

7. A traction drive type continuously variable transmission as set forth in claim 2, characterized by including a pair of face cams, movable and fixed, supported coaxially with the first input/output shaft, the movable cam being movable axially of the first input/output shaft and being in direct or indirect contact with the V-pulley, the other face cam being fixed to the casing, the arrangement being such that when the movable face cam rotates, it moves toward or away from the fixed face cam, the movable cam rotating in operative association with the turning of the arm.

8. A traction drive type continuously variable transmission as set forth in claim 7, characterized in that the gear is supported coaxially with the turning shaft of the arm and meshes with the teeth formed in the movable face cam.

9. A traction drive type continuously variable transmission as set forth in claim 1, characterized in that the first input/output shaft is used as the input shaft, and the second input/output shaft is used as the output shaft.

10. A traction drive type continuously variable transmission as set forth in claim 1, characterized in that when the transmission torque increases, said ring moves in the direction to be pressed into between the pulley members.

11. A traction drive type continuously variable transmission as set forth in claim 1, characterized in that a screw for converting rotational motion into linear motion is utilized as means for axially moving the pulley members to change the groove width.

12. A traction drive type continuously variable transmission as set forth in claim 11, characterized in that an elastic member is disposed in an axial clearance between the pulley member and the feed screw shaft therefor.

13. A traction drive type continuously variable transmission as set forth in claim 11, characterized in that two such transmissions are connected in series.

14. A traction drive type continuously variable transmission as set forth in claim 11, characterized the angle θ

of the pulley members is in the range of 3-7 degrees.

15. A traction drive type continuously variable transmission as set forth in claim 2, characterized in that said guide rollers are in rolling contact with said ring.

16. A traction drive type continuously variable transmission as set forth in claim 2, characterized in that said guide rollers are in slide contact with said ring.

17. A traction drive type continuously variable transmission as set forth in claim 3, characterized in that said guide rollers are in slide contact with said ring.

18. A traction drive type continuously variable transmission as set forth in claim 2, characterized in that the change of the groove width of the V-pulley is operatively associated with the movement of said ring.

19. A traction drive type continuously variable transmission as set forth in claim 3, characterized in that the change of the groove width of the V-pulley is operatively associated with the movement of said ring.

20. A traction drive type continuously variable transmission as set forth in claim 4, characterized in that the change of the groove width of the V-pulley is operatively associated with the movement of said ring.

21. A traction drive type continuously variable transmission as set forth in claim 15, characterized in that the change of the groove width of the V-pulley is operatively associated with the movement of said ring.

22. A traction drive type continuously variable transmission as set forth in claim 5, characterized in that the change of the groove width of the V-pulley is operatively associated with the movement of said ring.

23. A traction drive type continuously variable transmission as set forth in claim 16, characterized in that the change of the groove width of the V-pulley is operatively associated with the movement of said ring.

24. A traction drive type continuously variable transmission as set forth in claim 17, characterized in that the change of the groove width of the V-pulley is operatively associated with the movement of said ring.

25. A traction drive type continuously variable transmission as set forth in claim 2, characterized in that the first input/output shaft is used as the input shaft, and the second input/output shaft is used as the output shaft.

26. A traction drive type continuously variable transmission as set forth in claim 3, characterized in that the first input/output shaft is used as the input shaft, and the second input/output shaft is used as the output shaft.

27. A traction drive type continuously variable transmission as set forth in claim 7, characterized in that the first input/output shaft is used as the input shaft, and the second input/output shaft is used as the output shaft.

28. A traction drive type continuously variable transmission as set forth in claim 8, characterized in that the first input/output shaft is used as the input shaft, and the second input/output shaft is used as the output shaft.

29. A traction drive type continuously variable transmission as set forth in claim 2, characterized in that when the transmission torque increases, said ring moves in the direction to be pressed into between the pulley members.

30. A traction drive type continuously variable transmission as set forth in claim 3, characterized in that when the transmission torque increases, said ring moves in the direction to be pressed into between the pulley members.

31. A traction drive type continuously variable transmission as set forth in claim 7, characterized in that when the transmission torque increases, said ring moves in the direction to be pressed into between the pulley members.

32. A traction drive type continuously variable transmission as set forth in claim 8, characterized in that when the transmission torque increases, said ring moves in the direction to be pressed into between the pulley members.