Ball type continuously variable transmission

• US 9,194,472 B2
• Filed: 11/18/2014
• Issued: 11/24/2015
• Est. Priority Date: 03/14/2013
• Status: Active Grant

• Current Assignee: DANA Limited (Caterpillar Incorporated)
• Original Assignee: DANA Limited (Caterpillar Incorporated)
• Inventors: Versteyhe, Mark R. J., Duchene, Thibaut E., Byltiauw, Matthias W. J.
• Primary Examiner(s): Holmes, Justin
• Application Number:
  US14/546,603
• Publication Number:
  US 20150111683A1
• Time in Patent Office: 371 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: F16H 15/28 with external friction surface
• 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 2037/026 CVT layouts with particular features of reversing gear, e.g. to achieve compact arrangement
• 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 2037/0893 characterised in the ratio of the continuously variable transmission is different from zero when the output shaft speed is zero
• CPC Class Codes: F16H 2200/2005 with one sets of orbital gears
• CPC Class Codes: F16H 2200/2007 with two sets of orbital gears
• 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 variable transmission includes an input shaft, a planetary gear set drivingly engaged with a variator comprising, a variator carrier assembly, a first ring assembly, and a second ring assembly; and the output shaft, arranged to produce transmissions with continuously variable or infinitely variable output ratios.

Claims

1. A variable transmission comprising:

an input shaft;

an asymmetric variator comprising a first ring assembly coupled to the input shaft, a carrier assembly comprising a plurality of tiltable variator balls drivingly engaged with the first ring assembly, and a second ring assembly drivingly engaged with the tiltable variator balls; and

a planetary gearset comprising a planet carrier drivingly engaged with the input shaft, a ring gear drivingly engaged with the second ring assembly of the variator, and a sun gear drivingly engaged with an output of the vehicle,

wherein the asymmetric variator is configured to perform a power-splitting function of a speed ratio shifter and thereby alters a gearing range of a power source.

2. The variable transmission of claim 1, wherein the asymmetric variator is configured to split power of the input shaft between the asymmetric variator and a mechanical path going directly to the output of the vehicle through the planetary gear set.

3. The variable transmission of claim 1, wherein the asymmetric variator is configured to shift a range of speed ratios to higher or lower values.

4. The variable transmission of claim 1, wherein the first ring assembly comprises a first ring assembly engagement portion that is drivingly engaged with the tiltable variator balls, and second ring assembly comprises a second ring assembly engagement portion that is drivingly engaged with the tiltable variator balls, and wherein the first ring assembly engagement portion is offset from the second ring assembly engagement portion such that a speed ratio is greater than 1.0 or less than 1.0 when the tiltable variator balls are not tilted.

5. The variable transmission of claim 4, wherein the speed ratio is greater than 1.0 when angle between the vertical and the first ring assembly is greater than the angle between the vertical and the second ring assembly when a ball axle of the tiltable variator balls is 0 degrees (horizontal).

6. The variable transmission of claim 4, wherein the speed ratio is less than 1.0 when angle between the vertical and the first ring assembly is less than the angle between the vertical and the second ring assembly when a ball axle of the tiltable variator balls is 0 degrees (horizontal).

7. The variable transmission of claim 1, wherein the variator and the planetary gearset are configured to provide a standstill and reverse function in an infinitely variable planetary (IVP) mode.

8. The variable transmission of claim 1, further comprising a first and second ball ramp disposed on either side of the variator for providing a clamping force for torque transfer.

9. The variable transmission of claim 1, wherein the input shaft is coupled to a damper and an output of a power source.

10. The variable transmission of claim 1, further comprising a traction fluid in the variator.

11. A means of conveyance comprising the variable transmission of claim 1.

12. The variable transmission of claim 1, whereby the transmission simultaneously allows for part of the power from the input shaft to flow through the asymmetric variator, the planetary ring gear, planet gears and the sun gear, and part of the power will flow directly through the planet carrier, planet gears and sun gear of the planetary gearset prior to reaching the output of the vehicle.