CONTINUOUSLY VARIABLE GEAR TRANSMISSION

• US 20090082169A1
• Filed: 12/18/2006
• Published: 03/26/2009
• Est. Priority Date: 12/30/2005
• Status: Abandoned Application

• Current Assignee: Enviolo BV
• Original Assignee: Fallbrook Technologies Incorporated
• Inventors: Kolstrup, Anders
• Application Number:
  US12/159,688
• Publication Number:
  US 20090082169A1
• Time in Patent Office: Days
• US Class Current: 476/38
• CPC Class Codes: F16H 15/28 with external friction surface
• CPC Class Codes: F16H 15/40 in which two members co-operative by means of balls, or rollers of uniform effective diameter, not mounted on shafts

Abstract

A continuously variable gear is described having an input shaft (1), a plurality of traction balls (2) distributed radially around the axis, each traction ball (2) is mounted on an axle (3) passing there through, the axles (3) are tiltable in the radial grooves (4) in the housing (5) and support plate (6), To control the position of the traction bails (2), the axles are guided in curved slots (13) of turnable iris plate (7). To control the axial placement of the traction balls (2), there is a rotatable input disc (8) positioned adjacent to the traction balls (2), a rotatable output disc (9) positioned adjacent to the traction balls (2) opposite the input disc (8), and a pre-spanning ring around the traction balls (2) such that each of the traction balls (2) is making three-point contact with the input disc (8), the output disc (9) and the pre-spanning ring (11), the contact surface of the pre-spanning ring (11) having a specific curvature larger than the radius of the traction balls (2).

Claims

1-14. -14. (canceled)

15. An apparatus for facilitating control of the ratio of a continuously variable transmission (CVT), the apparatus comprising:

a first member having a first plurality of radial grooves;

a second member having a second plurality of radial grooves;

wherein the first and second pluralities of radial grooves are arranged angularly about an axis; and

wherein the first and second members are configured for rotation relative to one another such that during operation of the CVT the first plurality of radial grooves can be angularly misaligned relative to the second plurality of grooves.

16. The apparatus of claim 15, wherein the first member comprises a stationary member.

17. The apparatus of claim 16, wherein the second member comprises a support plate configured for rotation relative to the first member.

18. The apparatus of claim 15, wherein the first member comprises a housing member.

19. The apparatus of claim 18, wherein the second member comprises a support plate.

20. The apparatus of claim 19, further comprising an actuator housing and an actuator arm, the actuator housing coupled to the support plate, and the actuator arm coupled to a mechanism for tilting a plurality of traction balls of a CVT.

21. A method for facilitating control of the ratio of a continuously variable transmission (CVT), the method comprising:

providing a plurality of traction balls;

providing each traction ball with a ball axle about which the traction ball rotates;

providing a first plurality of grooves for engaging a first end of the ball axles;

providing a second plurality of grooves for engaging a second end of the ball axles; and

arranging the first and second plurality of grooves relative to one another such that during operation of the CVT the first plurality of grooves can be misaligned relative to the second plurality of grooves.

22. The method of claim 21, wherein the first and second plurality of grooves comprise radial grooves.

23. The method of claim 21, wherein first plurality of grooves is part of a housing.

24. The method of claim 23, wherein the second pluraliy of grooves is part of a support plate.

25. The method of claim 24, further comprising providing an actuator housing and an actuator arm, the actuator housing being coupled to the support plate, and the actuator arm being coupled to a mechanism for tilting the plurality of traction balls.

26. A method of controlling the ratio of a continuously variable transmission, the method comprising:

providing a plurality of traction balls;

providing a first plurality of radial grooves for engaging a first end of each of the ball axles;

providing a second plurality of radial grooves for engaging a second end of each of the ball axles; and

providing a second plurality of radial grooves for engaging a second end of the ball axles; and

rotating the first and second plurality of radial grooves relative to one another.

27. The method of claim 26, further comprising providing an input disc in contact with the plurality of balls, and wherein a clockwise rotation of the input disc and a clockwise rotation of the second plurality of grooves results in the ball axles being tilted in a first direction in the radial grooves.

28. The method of claim 27, wherein a counterclockwise rotation of the second plurality of grooves results in the ball axles being tilted in a second direction in the radial grooves.

29. The method of claim 26, wherein providing a second plurality of radial grooves comprises providing a support plate comprising a plurality of radial grooves.

30-35. -35. (canceled)

36. A continuously variable transmission (CVT) comprising:

a plurality of traction balls angularly arrayed about a shaft, each traction ball provided with a ball axle about which the ball rotates;

an input disc in contact with the traction balls;

an output disc in contact with the traction balls;

a prespanning ring in contact with the balls;

wherein the input and output discs contact the balls at a position that is radially inward relative to the position where the prespanning ring contacts the balls; and

wherein the prespanning ring is configured to translate axially when the ball axles are tilted.

37. A continuously variable transmission (CVT) comprising:

a shaft;

a plurality of traction balls arrayed angularly about a longitudinal axis of the shaft;

a plurality of tiltable ball axles, each ball axle corresponding to a traction ball;

a first plurality of radial grooves engaging a first end of the balls axles;

a second plurality of radial grooves engaging a second end of the ball axles; and

wherein the first plurality of radial grooves is configured for rotation relative to the second plurality of radial grooves such that rotation of the first plurality of radial grooves causes the ball axles to tilt in the first and second pluralities of radial grooves.

38. The CVT of claim 37, wherein the first plurality of grooves are formed in a support plate.

39. The CVT of claim 38, wherein the second plurality of grooves is stationary and the support plate is configured to have minor rotational play about its ideal aligned position.

40. The CVT of claim 37, further comprising an input disc, an output disc, and a prespanning ring, wherein the input disc, output disc, and prespanning ring each contacts the plurality of traction balls.