Continuously variable transmission

• US 7,014,591 B2
• Filed: 12/06/2004
• Issued: 03/21/2006
• Est. Priority Date: 09/02/1997
• Status: Expired due to Term

• Current Assignee: Fallbrook Intellectual Property Company LLC (Fallbrook Technologies Incorporated)
• Original Assignee: Fallbrook Technologies Incorporated
• Inventors: Miller, Donald C.
• Primary Examiner(s): Wright, Dirk
• Application Number:
  US11/005,673
• Publication Number:
  US 20050113208A1
• Time in Patent Office: 470 Days
• Field of Search: 475/189, 475/192, 475/195, 476/37, 476/38
• US Class Current: 476/37
• CPC Class Codes: B62M 11/00 Transmissions characterised by the use of interengaging toothed wheels or frictionally-engaging wheels with roller engaging the periphery of ground wheel B62M13/00
• CPC Class Codes: F16H 15/28 with external friction surface
• CPC Class Codes: F16H 61/664 Friction gearings

Abstract

A continuously variable transmission is disclosed for use in rotationally or linearly powered machines and vehicles. The single axle transmission provides a simple manual shifting method for the user. An additional embodiment is disclosed which shifts automatically dependent upon the rotational speed of the wheel. Further, the practical commercialization of traction roller transmissions requires improvements in the reliability, ease of shifting, function and simplicity of the transmission. The disclosed transmission may be used in vehicles such as automobiles, motorcycles, and bicycles. The transmission may, for example, be driven by a power transfer mechanism such as a sprocket, gear, pulley or lever, optionally driving a one way clutch attached at one end of the main shaft.

Claims

1. A tractor comprising:

a power source;

a continuously variable transmission coupled to the power source, the continuously variable transmission having a plurality of power adjusters;

a shifting mechanism for the continuously variable transmission, the shifting mechanism comprising;

at least one platform having a convex surface; and

a plurality of spindle supports engaged with the platform such that the spindle supports adjust the axis of rotation of the power adjusters in response to axial movement of the platform along a longitudinal axis of the transmission.

2. The tractor of claim 1, further comprising a spindle for each power adjuster, the spindle located within the power adjuster, and wherein each spindle support comprises a bore for receiving one end of a spindle.

3. The tractor of claim 2, wherein each spindle support comprises at least one wheel that is slidingly engaged to the convex surface of the platform.

4. The tractor of claim 1, additionally comprising:

a hollow shaft having at least one slot;

a sleeve that is slidingly and coaxially positioned over the hollow shaft;

a pin contacting the sleeve through the slot in the hollow shaft; and

wherein the platform contacts the sleeve and moves axially in response to axial movement of the sleeve and the pin.

5. A method of regulating torque transmission in a tractor, the method comprising:

providing a torque input from a power source of the tractor;

applying, directly or indirectly, the torque input to a first rotatable member mounted on a shaft;

contacting the first rotatable member to at least one traction roller having a spindle about which the traction roller rotates;

contacting the traction roller to a second rotatable member mounted on the shaft;

attaching a spindle support to one end of the spindle; and

providing a platform having a convex surface and adapted to engage the spindle support such that the spindle support adjusts an axis of rotation of the traction roller in response to at least in part an axial movement of the platform along a longitudinal axis of the shaft.

6. The method of claim 5, further comprising mounting a rotatable annular member on the shaft and positioning the annular member between the first and second rotatable members.

7. The method of claim 6, further comprising frictionally contacting the traction roller to the annular member.

8. The method of claim 7, further comprising sliding the annular member axially along the shaft in response to an axial sliding of the platform.

9. The tractor of claim 5, wherein applying the torque input comprises applying indirectly the torque input.

10. A tractor comprising:

a power source;

a continuously variable transmission coupled to the power source, the continuously variable transmission comprising;

a rotatable driving member mounted on a shaft;

a plurality of power adjusters in frictional contact with the driving member;

a rotatable support member mounted on the shaft, capable of axial movement along the shaft, and in frictional contact with the power adjusters; and

a first platform positioned on a first end of the support member and adapted to move axially along the shaft with the support member.

11. The tractor of claim 10, further comprising a rotatable driven member in frictional contact with the power adjusters and the support member.

12. The tractor of claim 11, further comprising a second platform positioned on the second end of the support member and adapted to move axially along the shaft with the support member.

13. The tractor of claim 12, wherein the first and second platforms each comprises a convex surface.

14. The tractor of claim 13, wherein each of the power adjusters is spherical in shape and comprises a through central bore.

15. The tractor of claim 14, further comprises one spindle for each power adjuster, the spindle positioned in the central bore.

16. The tractor of claim 15, further comprising at least one spindle support for each spindle, the spindle support having a bore for receiving one end of the spindle.

17. The tractor of claim 16, wherein the spindle support tilts the axis of rotation of its corresponding power adjuster by adjusting the position of the spindle in response to an axial movement of at least one of the first and second platforms.

18. The tractor of claim 10, wherein the power source comprises an internal combustion engine.

19. The tractor of claim 18, wherein the internal combustion engine comprises a diesel engine.

20. The tractor of claim 10, wherein the power source comprises an electric motor.