BALANCED SPLIT SUN ASSEMBLIES WITH INTEGRATED DIFFERENTIAL MECHANISMS, AND VARIATORS AND DRIVE TRAINS INCLUDING BALANCED SPLIT SUN ASSEMBLIES

• US 20160290451A1
• Filed: 10/30/2015
• Published: 10/06/2016
• Est. Priority Date: 03/31/2015
• Status: Active Grant

• Current Assignee: Fallbrook Intellectual Property Company LLC (Fallbrook Technologies Incorporated)
• Original Assignee: Fallbrook Intellectual Property Company LLC (Fallbrook Technologies Incorporated)
• Inventors: Lohr, Charles B.
• Granted Patent: US 10,400,872 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F16H 15/28 with external friction surface
• 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 37/022 the toothed gearing having orbital motion
• CPC Class Codes: F16H 37/086 CVT using two coaxial friction members cooperating with at least one intermediate friction member

Abstract

A balanced split sun assembly with an integrated differential mechanism allows power to be transferred from a sun assembly to a plurality of ball planets, or allows power to be transferred from a plurality of ball planets to a sun assembly, while minimizing sliding, spin, axial pull, or other unwanted effects on the sun assembly. A differential mechanism, including offset mechanisms, allows torque to be divided between multiple split sun rolling elements. Variations in design of a split sun assembly allow for ease of manufacture, ease of assembly, and ease of adjustment.

Claims

1. A sun assembly for a transmission with an array of ball planets, the sun assembly comprising:

a first sun rolling element rotatable about a central axis, the first sun rolling element shaped for contact with the array of ball planets;

a second sun rolling element rotatable about the central axis, the second sun rolling element shaped for contact with the array of ball planets; and

a torque differential mechanism coupled to each of the first sun rolling element and the second sun rolling element, wherein each of the first sun rolling element and the second sun rolling element transfer power independently of the other of the first sun rolling element and the second sun rolling element.

2. The sun assembly of claim 1, wherein the torque differential mechanism is coupled to a power source.

3. The sun assembly of claim 1, wherein the torque differential mechanism is coupled to a power load.

4. The sun assembly of claim 1, further comprising an axial force balancing mechanism configured to apply a preload on one of the first sun rolling element and the second sun rolling element.

5. The sun assembly of claim 4, wherein the axial force balancing mechanism comprises a resilient member in contact with one of the first sun rolling element or the second sun rolling element.

6. The sun assembly of claim 5, further comprising a rigid member, wherein the resilient member is configured to resist axial forces up to a predetermined gap, and wherein the rigid member is configured to counteract axial forces.

7. The sun assembly of claim 4, wherein the axial force balancing mechanism comprises a hydraulic system.

8. A variator, comprising:

an array of ball planets rotatable about a longitudinal axis;

a first ring in contact with the array of ball planets and orbital about the longitudinal axis, the first ring being on a first side of the array of ball planets;

a second ring in contact with the array of ball planets and orbital about the longitudinal axis, the second ring being on a second side of the array of ball planets;

a first sun rolling element with a first central axis, the first sun rolling element shaped for contact with the array of ball planets;

a second sun rolling element with an axis coincident with the first central axis, the second sun rolling element shaped for contact with the array of ball planets; and

a torque differential mechanism coupled to each of the first sun rolling element and the second sun rolling element, wherein each of the first sun rolling element and the second sun rolling element transfer power independently of the other of the first sun rolling element and the second sun rolling element.

9. The variator of claim 8, wherein the torque differential mechanism comprises a roller element interposed between the first sun rolling element and the second sun rolling element.

10. The variator of claim 8, wherein the torque differential mechanism is offset from the first and second sun rolling elements.

11. The variator of claim 10, comprising a first lubrication system for the sun assembly and a second lubrication system for the differential mechanism.

12. The variator of claim 8, wherein the differential mechanism comprises a bevel gear mechanism.

13. The variator of claim 8, wherein the torque differential mechanism assembly allows the first sun rolling element and the second sun rolling element to apply a balanced torque to the plurality of ball planets.

14. A drivetrain comprising:

a power source; and

a variator coupled to the power source, the variator comprising;

an array of ball planets orbital about a longitudinal axis;

a first ring in contact with the array of ball planets and orbital about the longitudinal axis, the first ring being on a first side of the array of ball planets;

a second ring in contact with the array of ball planets and orbital about the longitudinal axis, the second ring being on a second side of the array of ball planets;

a first sun rolling element with a first central axis, the first sun rolling element shaped for contact with the array of ball planets;

a second sun rolling element with an axis coincident to the first central axis, the second sun rolling element shaped for contact with the array of ball planets. The drivetrain of claim 14, wherein the variator is coupled to the power source via a shaft.

18. The drivetrain of claim 14, wherein the variator is coupled to a power load via one of the first or second rings.

16. The drivetrain of claim 15, wherein the shaft extends through the variator.

17. The drivetrain of claim 16, further comprising a planetary gear set, wherein the shaft extends through the variator to engage the planetary gear set, wherein the planetary gear set is operably coupled to the first ring, wherein a portion of the power generated by the power source enters the variator via the first sun rolling element and the second sun rolling element, wherein a portion of the power generated by the power source enters the variator through the first ring, and wherein the power exits the variator via the second ring.