Continuously variable transmission

• US 7,762,920 B2
• Filed: 08/20/2007
• Issued: 07/27/2010
• Est. Priority Date: 10/05/2004
• Status: Expired due to Fees

• Current Assignee: Fallbrook Intellectual Property Company LLC (Fallbrook Technologies Incorporated)
• Original Assignee: Fallbrook Technologies Incorporated
• Inventors: Lohr, Charles B, Simister, Matthew P, Smithson, Robert A, Nichols, Jon M, Thomassy, Fernand A, Poth, Wesley R, Dawe, Daniel J, Miller, Donald C, Armstrong, Oronde J, Pohl, Brad P
• Primary Examiner(s): Joyce; William C
• Application Number:
  US11/841,957
• Publication Number:
  US 20080032853A1
• Time in Patent Office: 1,072 Days
• Field of Search: 476/8, 476/36, 476/38, 476/37
• US Class Current: 476/36
• CPC Class Codes: B62M 23/00 Transmissions characterised by use of other elements; Other transmissions
• CPC Class Codes: B62M 9/00 Transmissions characterised by use of an endless chain, belt, or the like cycle chain guards B62J13/00
• CPC Class Codes: F16H 15/28 with external friction surface
• CPC Class Codes: F16H 15/50 Gearings providing a continuous range of gear ratios
• CPC Class Codes: F16H 15/503 in which two members co-operate by means of balls or rollers of uniform effective diameter, not mounted on shafts
• CPC Class Codes: Y10T 29/49462 Gear making
• CPC Class Codes: Y10T 29/49464 Assembling of gear into force transmitting device
• CPC Class Codes: Y10T 29/49467 Gear shaping
• CPC Class Codes: Y10T 29/4984 Retaining clearance for motion between assembled parts

Abstract

A continuously variable transmission (CVT) having a main shaft configured to support and position various components of the CVT. Shift cam discs cooperate with ball-leg assemblies to shift the transmission ration of the CVT. Load cam discs, a torsion disc, rolling elements, and a hub cap shell are configured to generate axial force, transmit torque, and manage reaction forces. In one embodiment, a splined input shaft and a torsion disc having a splined bore cooperate to input torque into the variator of the CVT. Among other things, various ball axles, axle-ball combinations, and reaction force grounding configurations are disclosed. In one embodiment, a CVT having axial force generation means at both the input and output elements is disclosed.

Claims

1. A ring for transmitting torque in a continuously variable transmission (CVT), the ring comprising:

a contact surface engaging a plurality of balls of the CVT, the contact surface having a flat profile;

a splined bore adapted to transfer torque;

an annular body connecting the contact surface to the splined bore, the annular body having an inner, an outer circumference, a front surface and a back surface, the back surface located on an opposite surface with respect to the front surface;

an oil port formed on the annular body;

wherein the back surface comprises a plurality of ramps inclined at an angle, the ramps arranged to contact a plurality of cam rollers of the CVT;

wherein the contact surface is arranged at a distal location relative to the splined bore, the contact surface in proximity to the outer circumference of the annular body; and

wherein the splined bore is located on the inner circumference of the annular body.

2. The ring of claim 1, wherein the contact surface, the splined bore, and the annular body are formed in a single piece.

3. The ring of claim 1, wherein when the ring is viewed in cross section the contact surface is on a plane that is oblique to an axis perpendicular to the splined bore.

4. The ring of claim 3, wherein the oil port extends from the outer circumference to the inner circumference.

5. A torque transmission system for a continuously variable transmission CVT, the torque transmission system comprising:

a ring comprising;

a contact surface engaging to a plurality of balls of the CVT, the contact surface having a flat profile;

a splined bore adapted to transfer torque;

an annular body connecting the contact surface to the splined bore, the annular body having an inner and an outer circumference;

an oil port formed on the annular body;

wherein the annular body comprises a plurality of ramps, the ramps arranged on a surface opposite of the contact surface, wherein the ramps incline from the surface at an angle, the ramps arranged to contact a plurality of cam rollers of the CVT;

wherein the contact surface is arranged at a distal location relative to the splined bore, the contact surface in proximity to the outer circumference of the annular body;

wherein the splined bore is located on the inner circumference of the annular body; and

a ring driver having a plurality of splines configured to mate with the splined bore.

6. The torque transmission system of claim 5, wherein the ring driver further comprises a flange adapted to contact the annular body.

7. The torque transmission system of claim 5, wherein the ring contacts each ball at a point that is radially outward relative to the center of the ball.