Ball type CVT/IVT including planetary gear sets

• US 9,052,000 B2
• Filed: 09/03/2013
• Issued: 06/09/2015
• Est. Priority Date: 09/07/2012
• Status: Active Grant

• Current Assignee: DANA Limited (Caterpillar Incorporated)
• Original Assignee: DANA Limited (Caterpillar Incorporated)
• Inventors: Cooper, Kenneth E.
• Primary Examiner(s): Holmes, Justin
• Application Number:
  US14/017,054
• Publication Number:
  US 20140194242A1
• Time in Patent Office: 644 Days
• Field of Search: 475/198, 475/204, 475/207, 475214-217
• 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 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 2037/0873 with switching, e.g. to change ranges
• 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 37/0853 CVT using friction between rotary members having a first member of uniform effective diameter cooperating with different parts of a second member

Abstract

Disclosed herein are power transmissions having one or more operational modes, for example, a continuously variable transmission (CVT) mode, an infinitely variable transmission (IVT) mode, and an IVT/CVT mode, that can be selected for by engaging different clutches and brakes. Disclosed herein are power transmissions comprising a power input shaft, one or more planetary gear sets, a variator (such as a CVT), and one or more clutches and brakes. In some embodiments, a first brake selects an IVT mode, a second brake selects a CVT mode, and a third brake selects an IVT/CVT mode.

Claims

1. A power transmission apparatus comprising:

a power input shaft;

a first planetary gear set coaxially located and mechanically coupled to the power input shaft;

a variator coaxially located and mechanically coupled to the first planetary gear set; and

one or more clutches and brakes for switching among an infinitely variable transmission mode and a second operational mode of the power transmission apparatus,

wherein said variator is a continuously variable planetary comprising an input ring, planetary balls, axles, an idler and an output ring.

2. The power transmission apparatus of claim 1, wherein a second planetary gear set is coaxially located and coupled to an output of the variator and to a final drive and differential.

3. The power transmission apparatus of claim 2, wherein the one or more clutches and brakes comprises an overdrive clutch for affecting a speed increase.

4. The power transmission apparatus of claim 2, wherein a variator output ring is coupled to a carrier of the second planetary gear set.

5. The power transmission apparatus of claim 2, wherein the second planetary can be locked to turn with a 1:

1 ratio, or can provide a speed increase with an overdrive clutch.

6. The power transmission apparatus of claim 1, further comprising a traction fluid lubricant.

7. The power transmission apparatus of claim 1, wherein the first planetary gear set is further located between the variator and the power input shaft.

8. The power transmission apparatus of claim 1, wherein the power input shaft is connected to the sun of the first planetary gear set.

9. The power transmission apparatus of claim 1, wherein the one or more clutches and brakes are configured to be selectively engaged or released to switch among the infinitely variable transmission mode and the second operational mode of the power transmission apparatus.

10. The power transmission apparatus of claim 1, wherein the first planetary gear set comprises a ravigneaux gear set.

11. The power transmission apparatus of claim 1, wherein the first planetary gear set comprises a dual sun planetary gear set.

12. The power transmission apparatus of claim 11, wherein the dual sun planetary gearset comprises a first plane of gears including first planets, and a second plane of gears including second planets, wherein the first planets of the first plane of gears and the second planets of the second plane of gears are a single unit.

13. The power transmission apparatus of claim 11, wherein a variator input ring is coupled to the output sun of the first planetary gear set.

14. The power transmission apparatus of claim 1, further comprising a power output mechanically coupled to the variator, wherein the power output comprises an output gear set mechanically coupled to a shaft of the power output for transmitting power from the variator to a differential box.

15. The power transmission apparatus of claim 1, whereby the apparatus allows for mode shifting between the continuously variable mode and infinitely variable mode with a minimum number of clutches and brakes.

16. The power transmission apparatus of claim 1, wherein the first planetary gear set comprises a three sun planetary gear set.

17. The power transmission apparatus of claim 1 wherein the variator is coupled to a sun of the first planetary gear set.

18. The power transmission apparatus of claim 1, wherein the variator is coupled to a carrier of the first planetary gear set.

19. The power transmission apparatus of claim 1, wherein the variator comprises a continuously variable transmission.

20. The power transmission apparatus of claim 1, wherein the one or more clutches and brakes comprises a first clutch or brake for selecting an infinitely variable transmission mode of the power transmission apparatus.

21. The power transmission apparatus of claim 20, wherein the first clutch or brake is configured to couple to an output planet carrier of the first planetary gear set.

22. The power transmission apparatus of claim 20, wherein a second clutch or brake is configured to couple to a sun of the first planetary gear set.

23. The power transmission apparatus of claim 1, wherein the one or more clutches and brakes comprises a second clutch or brake for selecting a continuously variable transmission mode of the power transmission apparatus.

24. The power transmission apparatus of claim 23, wherein the second clutch or brake is configured to couple to an output of a sun gear of the first planetary gear set.

25. The power transmission apparatus of claim 1, wherein the one or more clutches and brakes comprises a third clutch or brake for selecting an infinitely and continuously variable transmission mode of the power transmission apparatus.

26. The power transmission apparatus of claim 25, wherein the third clutch or brake is configured to couple to a ring gear of the first planetary gear set.

27. The power transmission apparatus of claim 25, wherein the third clutch or brake is configured to couple to a sun of the first planetary gear set.