Continuously variable transmission

• US 8,628,443 B2
• Filed: 06/21/2013
• Issued: 01/14/2014
• Est. Priority Date: 02/28/2003
• Status: Active Grant

• Current Assignee: Fallbrook Intellectual Property Company LLC (Fallbrook Technologies Incorporated)
• Original Assignee: Fallbrook Intellectual Property Company LLC (Fallbrook Technologies Incorporated)
• Inventors: Miller, Donald C., Allen, David J., Smithson, Robert A.
• Primary Examiner(s): Wright, Dirk
• Application Number:
  US13/923,611
• Publication Number:
  US 20130281256A1
• Time in Patent Office: 207 Days
• Field of Search: None
• US Class Current: 475/189
• CPC Class Codes: B62M 11/04 of changeable ratio
• CPC Class Codes: B62M 11/14 with planetary gears
• CPC Class Codes: B62M 9/08 involving eccentrically- mounted or elliptically-shaped driving or driven wheel; with expansible driving or driven wheel
• 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
• 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: F16H 15/52 in which a member of uniform effective diameter mounted on a shaft may co-operate with different parts of another member
• CPC Class Codes: F16H 2037/088 Power split variators with summing differentials, with the input of the CVT connected or connectable to the input shaft
• CPC Class Codes: F16H 2037/101 Power split variators with one differential at each end of the CVT
• CPC Class Codes: F16H 37/084 at least one power path being a continuously variable transmission, i.e. CVT
• CPC Class Codes: F16H 37/0853 CVT using friction between rotary members having a first member of uniform effective diameter cooperating with different parts of a second member
• CPC Class Codes: F16H 37/086 CVT using two coaxial friction members cooperating with at least one intermediate friction member
• CPC Class Codes: F16H 61/6649 characterised by the means for controlling the torque transmitting capability of the gearing
• CPC Class Codes: F16H 63/067 mechanical actuating means
• CPC Class Codes: Y10T 29/49464 Assembling of gear into force transmitting device
• CPC Class Codes: Y10T 408/65 Means to drive tool

Abstract

A variable speed transmission having a plurality of tilting balls and opposing input and output discs is illustrated and described that provides an infinite number of speed combinations over its transmission ratio range. The use of a planetary gear set allows minimum speeds to be in reverse and the unique geometry of the transmission allows all of the power paths to be coaxial, thereby reducing overall size and complexity of the transmission in comparison to transmissions achieving similar transmission ratio ranges.

Claims

1. A cage for facilitating the support and guidance of a ball assembly in a continuously variable transmission, the cage comprising:

a first stator disc comprising a first plurality of angularly spaced apart radial curves, the first plurality of radial curves extending perpendicularly from a longitudinal axis; and

a second stator disc comprising a second plurality of angularly spaced apart radial curves, the second plurality of radial curves extending perpendicularly from the longitudinal axis, wherein the first and second stator discs are positioned such that the first plurality of radial curves is angularly offset relative to the second plurality of radial curves, wherein the first and second stator discs are adapted to be mounted coaxially with a longitudinal axis of the continuously variable transmission, and wherein the first stator disc and the second stator disc each comprise a bore adapted to engage a main shaft of the continuously variable transmission.

2. The cage of claim 1, wherein the first and second stator discs comprise a plurality of cutouts.

3. The cage of claim 1, further comprising a plurality of spacers configured to be positioned between the first stator disc and the second stator disc, wherein the spacers rigidly couple the first stator disc to the second stator disc.

4. The cage of claim 1, wherein the first stator disc and the second stator disc each comprises a substantially circular outer periphery.

5. The cage of claim 1, wherein the first and second stator discs each comprise a plurality of concave surfaces formed in between the curves.

6. The cage of claim 1, wherein the first plurality of radial curves are configured to receive a roller of a ball-leg assembly.

7. The cage of claim 1, wherein the second plurality of radial curves are configured to receive a roller of a ball-leg assembly.

8. A cage for facilitating the support and guidance of a ball-leg assembly in a continuously variable transmission, the cage comprising:

a first plurality of radial curves on an interior surface of the cage, wherein the first plurality of radial curves are spaced apart angularly about a longitudinal axis, the first plurality of radial curves extend perpendicularly from the longitudinal axis, and the first plurality of radial curves are configured to receive a roller of the ball-leg assembly;

a second plurality of radial curves on an interior surface of the cage, wherein the second plurality of radial curves are spaced apart angularly about the longitudinal axis, the second plurality of radial curves extend perpendicularly from the longitudinal axis, and the second plurality of radial curves are configured to receive the roller; and

a plurality of spacers adapted to be positioned between the first and second plurality of radial curves, wherein the first plurality of radial curves is spaced axially apart from the second plurality of curves, and wherein the first plurality of radial curves is offset angularly relative to the second plurality of curves.

9. The cage of claim 8, further comprising a plurality of concave surfaces located between each of the curves of the first plurality of curves and between each of the curves of the second plurality of curves.

10. The cage of claim 8, further comprising a central bore adapted to facilitate the mounting of the cage about the longitudinal axis.

11. The cage of claim 8, wherein the first plurality of curves and the second plurality of curves are formed, respectively, on a first stator disc and a second stator disc.

12. The cage of claim 8, wherein the first stator disc and the second stator disc each comprise a generally circular outer periphery.

13. The cage of claim 8, wherein the plurality of spacers rigidly couple the first plurality of radial curves to the second plurality of radial curves.

14. A cage for facilitating the support and guidance of a ball assembly in a continuously variable transmission, the cage comprising:

a first stator disc comprising a first plurality of angularly spaced apart radial curves extending perpendicularly from a longitudinal axis;

a second stator disc comprising a second plurality of angularly spaced apart radial curves extending perpendicularly from the longitudinal axis; and

a plurality of spacers configured to be positioned between the first stator disc and the second stator disc, wherein the spacers rigidly couple the first stator disc to the second stator disc, wherein the first and second stator discs are positioned such that the first plurality of radial curves is angularly offset relative to the second plurality of radial curves, and wherein the first and second stator discs each comprise a plurality of concave surfaces formed in between the radial curves.

15. The cage of claim 14, wherein the first and second stator discs are adapted to be mounted coaxially with a longitudinal axis of the continuously variable transmission.

16. A cage for facilitating the support and guidance of a ball assembly in a continuously variable transmission, the cage comprising:

a first plurality of radial curves on an interior surface of the cage, wherein the first plurality of radial curves are spaced apart angularly about a longitudinal axis, and the first plurality of radial curves extend perpendicularly from the longitudinal axis;

a second plurality of radial curves on an interior surface of the cage, wherein the second plurality of radial curves are spaced apart angularly about the longitudinal axis, and the second plurality of radial curves extend perpendicularly from the longitudinal axis;

a plurality of concave surfaces located between each of the curves of the first plurality of curves and between each of the curves of the second plurality of curves; and

a plurality of spacers adapted to be positioned between the first and second plurality of radial curves, wherein the first plurality of radial curves is spaced axially apart from the second plurality of curves, and wherein the first plurality of radial curves is offset angularly relative to the second plurality of curves.

17. The cage of claim 16, wherein the plurality of spacers rigidly couple the first plurality of radial curves to the second plurality of radial curves.