Ball type CVT with output coupled powerpaths

• US 9,599,204 B2
• Filed: 09/03/2013
• Issued: 03/21/2017
• 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., Byltiauw, Matthias W. J.
• Primary Examiner(s): Scott, Jacob S
• Assistant Examiner(s): Dang, Tinh
• Application Number:
  US14/425,600
• Publication Number:
  US 20150204429A1
• Time in Patent Office: 1,295 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 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 2200/2005 with one sets of orbital gears
• CPC Class Codes: F16H 2200/2038 with three engaging means
• 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

Abstract

Systems, devices, and methods are provided for the transmission of power in motor vehicles. Power can be transmitted in a smoother and more efficient manner, with smaller and even less mechanical components, by splitting torque into two or more torque paths. A power transmission apparatus comprises a power input shaft, a planetary gear set coupled to the power input shaft, and a variator, such as a continuously variable transmission (CVT), coupled to the gear set. The various components of the planetary gear set and the variator are arranged such that torque is split between two or more torque paths and then recombined before power is output to a gear box and a differential of the motor vehicle.

Claims

1. An apparatus for power transmission comprising:

a power input shaft;

an input planetary gear set engaged with the power input shaft;

a ball type variator comprising an input ring and an output ring engaged with the input gear set,

an output planetary gear set engaged with the variator, and

two clutches and one brake for switching between a plurality of operational modes of the power transmission apparatus,

wherein the apparatus is configured to split torque between a plurality of torque paths,

wherein the variator comprises a torsional continuously variable transmission (CVT),

wherein the input planetary gear set comprises a set of input planet gears, an input sun engaged with the input planet gears and with the input ring of the variator, an input carrier engaged with the input planet gears and with the power input shaft, and an input ring gear engaged with the input planet gears, and

wherein the output planetary gear set comprises a set of output planet gears, an output sun gear engaged with the power input shaft and with the output planet gears, an output carrier engaged with the output planet gears and with a gear box for outputting power from the apparatus, and an output ring gear engaged with the output planet gears and with the output ring of the variator.

2. The power transmission apparatus of claim 1, further comprising a counter shaft engaging the input ring gear of the input planetary gear set and the output ring gears of the output planetary gear sets.

3. The power transmission apparatus of claim 2, wherein the two clutches comprise a first clutch and a second clutch, the first clutch being configured to be engaged to mechanically couple the output sun with the output ring of the variator and the second clutch being configured to be engaged to mechanically couple the power input shaft with the output sun, and wherein the power transmission apparatus further comprises the brake for holding the output sun to achieve an additional operation mode of the power transmission apparatus.

4. The power transmission apparatus of claim 3, wherein the plurality of operational modes of the power transmission apparatus comprises a first mode, a second mode, and a third mode.

5. The power transmission apparatus of claim 4, wherein the first, second, and third modes comprise continuously variable transmission modes.

6. The power transmission apparatus of claim 4, wherein the first mode is selected by engaging the brake while releasing the first and second clutch.

7. The power transmission apparatus of claim 4, wherein the second mode is selected by engaging the second clutch while releasing the brake and the first clutch.

8. The power transmission apparatus of claim 4, wherein the third mode is selected by engaging the first clutch while releasing the brake and the second clutch.

9. The power transmission apparatus of claim 4, wherein torque is split into a first path through the variator and a second path through the countershaft in the first and third modes.

10. The power transmission apparatus of claim 4, wherein torque is split into a first path through the variator, a second path through the countershaft, and a third path between the power input shaft and the output sun gear of the output planetary gear set in the second mode.

11. The power transmission apparatus of claim 1, wherein the gear box is engaged with a differential.

12. The power transmission apparatus of claim 11, wherein the gear box comprises a three speed gear box.