Ball type CVT including a direct drive mode

• US 9,638,296 B2
• Filed: 09/05/2013
• Issued: 05/02/2017
• Est. Priority Date: 09/07/2012
• Status: Active Grant

• Current Assignee: DANA Limited (Caterpillar Incorporated)
• Original Assignee: DANA Limited (Caterpillar Incorporated)
• Inventors: Versteyhe, Mark R. J., Duchene, Thibaut E.
• Primary Examiner(s): YOUNG, EDWIN
• Application Number:
  US14/425,601
• Publication Number:
  US 20150354676A1
• Time in Patent Office: 1,335 Days
• Field of Search: None
• 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 2037/023 CVT's provided with at least two forward and one reverse ratio in a serial arranged sub-transmission
• CPC Class Codes: F16H 37/021 toothed gearing combined with continuous variable friction gearing

Abstract

Variable transmissions and drivelines using such transmissions having a direct drive mode, a reverse mode, and a continuously variable mode of operation using a continuously variable variator in combination with a gearbox having a one or two speed forward gear, a reverse gear, and a direct drive clutch. The direct drive clutch transfers power from the input shaft directly to the gearbox by running the variator in a unitary (1) speed ratio configuration, or by bypassing the variator altogether by using a set of clutches that disconnect the variator from the input shaft. Additional gears may be provided in the gearbox.

Claims

1. A vehicle transmission comprising:

an input shaft having a first direct drive shaft first member formed thereon;

an output shaft;

a variator comprising a first ring assembly drivingly engaged with the input shaft, a second ring assembly drivingly engaged with the output shaft, and a carrier assembly, wherein the carrier assembly comprises an annular arrangement of a plurality of tiltable variator balls each having a tiltable ball axle shaft;

a direct drive clutch comprising a first direct drive clutch member and a second direct drive clutch member formed on the output shaft drivingly engaged with the second ring assembly; and

a gearbox drivingly engaged with the second ring assembly and with the second direct drive clutch member through the output shaft, the gearbox comprising a first gear and a reverse gear;

wherein the vehicle transmission comprises a reverse mode, a direct drive mode, and a continuously variable mode.

2. The vehicle transmission of claim 1, wherein the gearbox comprises a second gear.

3. The vehicle transmission of claim 1, wherein the gearbox is drivingly linked to a differential of a vehicle output.

4. The vehicle transmission of claim 1, wherein the gearbox is drivingly linked to a differential of a vehicle output using a countershaft.

5. The vehicle transmission of claim 4, wherein the countershaft comprises a first countershaft gear, a reverse countershaft gear, and a pinion gear, and wherein a crown ring is drivingly engaged with a vehicle output.

6. The vehicle transmission of claim 5 wherein the first countershaft gear is selectively drivingly engaged with the first gear of the gearbox.

7. The vehicle transmission of claim 5 wherein the reverse countershaft gear is selectively drivingly engaged with the reverse gear of the gearbox.

8. The vehicle transmission of claim 5 wherein the reverse gear comprises a reverse gear idler between the reverse gear and the reverse countershaft gear.

9. The vehicle transmission of claim 5, wherein a reverse mode is enabled when a reverse clutch is engaged with the output shaft and the first gear is disengaged from the output shaft.

10. The vehicle transmission of claim 5, wherein a reverse mode is enabled when a reverse clutch is engaged with the output shaft and the first gear is disengaged from the first countershaft gear.

11. The vehicle transmission of claim 5, wherein the gearbox comprises a second gear, and the countershaft comprises a second countershaft gear.

12. The vehicle transmission of claim 11, wherein the second countershaft gear is selectively drivingly engaged with the second gear of the gearbox.

13. The vehicle transmission of claim 11, wherein a reverse mode is enabled when a reverse clutch is engaged with the output shaft, the first gear is disengaged from the output shaft, and the second gear is disengaged from the output shaft.

14. The vehicle transmission of claim 11, wherein a reverse mode is enabled when a reverse clutch is engaged with the output shaft, the first gear is disengaged from the first countershaft gear, and the second gear is disengaged from the second countershaft gear.

15. The vehicle transmission of claim 1, wherein disengaging the direct drive clutch results in continuously variable mode operation of the vehicle transmission.

16. The vehicle transmission of claim 15, wherein in continuously variable mode power is transferred through the first ring assembly, one or more balls of the carrier assembly, the second ring assembly, the gearbox and to the vehicle output.

17. The vehicle transmission of claim 15, wherein in direct drive mode power is transferred through directly from the input shaft to the gearbox.

18. The vehicle transmission of claim 15, wherein in direct drive mode the variator is free to turn.

19. The vehicle transmission of claim 1, wherein the gearbox increases the overall ratio spread and provides a reverse mode using the reverse gear.

20. The vehicle transmission of claim 1, wherein engaging the direct drive clutch results in direct drive mode.