HYBRID TRANSMISSION

• US 20110045931A1
• Filed: 08/20/2009
• Published: 02/24/2011
• Est. Priority Date: 08/20/2009
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (General Motors Company)
• Inventors: Holmes, Alan G., Raghavan, Madhusudan
• Granted Patent: US 8,371,983 B2
• Time in Patent Office: Days
• US Class Current: 475/221
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: F16H 2037/103 Power split variators with each end of the CVT connected or connectable to a Ravigneaux set
• CPC Class Codes: F16H 2037/104 Power split variators with one end of the CVT connected or connectable to two or more differentials
• CPC Class Codes: F16H 2200/2007 with two sets of orbital gears
• CPC Class Codes: F16H 2200/201 with three sets of orbital gears
• CPC Class Codes: F16H 2200/2023 using a Ravigneaux set with 4 connections
• CPC Class Codes: F16H 2200/2038 with three engaging means
• CPC Class Codes: F16H 3/728 with means to change ratio in the mechanical gearing
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A hybrid transmission is configured to transfer mechanical power to an output member and includes an input member, an output member, and a transmission case circumscribing first and second differential gear sets, each differential gear set including a plurality of meshingly engaged rotatable elements. The first differential gear set is configured with four nodes for transferring mechanical power, and the second differential gear set is configured with three nodes for transferring mechanical power. Two of the four nodes of the first differential gear set are continuously interconnected to two of the three nodes of the second differential gear set. A first torque transfer clutch is configured to selectively connect the input member to an internal combustion engine. First and second brake devices are configured to selectively interconnect elements of the first and second differential gear sets, the transmission case, the input member, and the output member.

Claims

1. Hybrid transmission configured to transfer mechanical power to an

output member, comprising:

an input member and an output member;

a transmission case circumscribing first and second differential gear sets, each differential gear set comprising a plurality of meshingly engaged rotatable elements;

the first differential gear set configured with four nodes for transferring mechanical power;

the second differential gear set configured with three nodes for transferring mechanical power;

two of the four nodes of the first differential gear set continuously interconnected to two of the three nodes of the second differential gear set; and

a first torque transfer clutch configured to selectively connect the input member to an internal combustion engine;

first and second brake devices configured to selectively interconnect elements of the first and second differential gear sets, the transmission case, the input member, and the output member.

2. The hybrid transmission of claim 1, further comprising a second torque transfer clutch configured to selectively interconnect elements of the first and second differential gear sets to effect fixed gear operation.

3. The hybrid transmission of claim 1, wherein a first one of the four nodes of the first differential gear set comprises a connecting point to selectively ground rotation of a first one of the elements of the first differential gear set to the transmission case by applying the second brake.

4. The hybrid transmission of claim 1, wherein a second one of the four nodes of the first differential gear set comprises a connecting point to continuously interconnect a second one of the elements of the first differential gear set to a first one of the elements of the second differential gear set.

5. The hybrid transmission of claim 4, wherein the second one of the four nodes of the first differential gear set comprises a connecting point to selectively ground rotation of the second one of the elements of the first differential gear set to the transmission case by applying the first brake.

6. The hybrid transmission of claim 4, wherein the second one of the four nodes of the first differential gear set further comprises a connecting point to transfer power between the second one of the elements of the first differential gear set and a first torque machine.

7. The hybrid transmission of claim 1, wherein a third one of the four nodes of the first differential gear set comprises a connecting point to transfer power between a third one of the elements of the first differential gear set and the output member.

8. The hybrid transmission of claim 1, wherein a fourth one of the four nodes of the first differential gear set comprises a connecting point to transfer power between a fourth one of the elements of the first differential gear set and a second one of the elements of the second differential gear set.

9. The hybrid transmission of claim 8, wherein the fourth one of the four nodes of the first differential gear set further comprises a connecting point to transfer power between the fourth one of the elements of the first differential gear set and a second torque machine.

10. Hybrid powertrain system configured to transfer mechanical power to a driveline, comprising:

an internal combustion engine configured to selectively transfer torque to an input member of a hybrid transmission via a first torque transfer clutch device,

a hybrid transmission including the input member, an output member, and a transmission case circumscribing first and second differential gear sets, each differential gear set comprising a plurality of meshingly engaged rotatable elements, the first differential gear set configured with four nodes for transferring mechanical power, the second differential gear set configured with three nodes for transferring mechanical power, two of the four nodes of the first differential gear set continuously interconnected to two of the three nodes of the second differential gear set, and first and second brake devices configured to selectively interconnect elements of the first and second differential gear sets, the transmission case, the input member, and the output member; and

first and second torque machines configured to transfer torque to selected nodes of one of the first and second differential gear sets.

11. The hybrid powertrain system of claim 10, wherein the hybrid transmission further comprises a second torque transfer clutch configured to selectively interconnect elements of the first and second differential gear sets to effect fixed gear operation.

12. The hybrid powertrain system of claim 10, wherein the hybrid transmission applies the first torque transfer clutch to transfer torque from one of the first and second torque machines to effect an engine start operating state.

13. The hybrid powertrain system of claim 12, wherein the hybrid transmission device is configured to spin the input member when the first torque transfer clutch is applied and the first torque machine rotates in a first direction and the second torque machine rotates in a second, opposite direction such that rotational speed of the output member is nil.

14. The hybrid powertrain system of claim 12, wherein the hybrid transmission is configured to spin the input member when the first torque transfer clutch is applied and the second torque machine rotates in a first direction such that rotational speed of the output member is in a positive direction.

15. The hybrid powertrain system of claim 10, wherein the engine is in an off state during powertrain operation in one of a reverse operating state, a low speed electric vehicle operating state, and a launch operating state.

16. The hybrid powertrain system of claim 15, wherein the hybrid transmission applies the first brake device to ground one of the elements of the first differential gear set to transfer tractive torque to the output member to effect the launch operating state.

17. The hybrid powertrain system of claim 15, wherein the hybrid transmission applies the first brake device to ground one of the elements of the first differential gear set to transfer tractive torque to the output member to effect the low speed electric vehicle operating state.

18. The hybrid powertrain system of claim 15, wherein the hybrid transmission applies the first brake device to ground one of the elements of the first differential gear set to transfer tractive torque to the output member to effect the reverse operating state.

19. The hybrid powertrain system of claim 10, wherein the hybrid transmission applies the second brake device to ground one of the elements of the first differential gear set to transfer tractive torque to the output member to effect a high speed electric vehicle operating state.

20. The hybrid powertrain system of claim 19, wherein the engine is in an off state during powertrain operation in the high speed electric vehicle operating state.

21. The hybrid powertrain system of claim 10, wherein the hybrid transmission applies the first torque transfer clutch to transfer tractive torque from the engine to the hybrid transmission to effect an electrically-variable transmission operating state.

22. The hybrid powertrain system of claim 21, wherein the engine is in an on state during powertrain operation in the electrically-variable transmission operating state.

23. Hybrid transmission configured to transfer mechanical power to an output member, comprising:

an input member and an output member;

a transmission case circumscribing first and second differential gear sets, each differential gear set comprising a plurality of meshingly engaged rotatable elements;

the first differential gear set configured with four nodes for transferring mechanical power;

the second differential gear set configured with three nodes for transferring mechanical power;

two of the four nodes of the first differential gear set continuously interconnected to two of the three nodes of the second differential gear set; and

a first torque transfer clutch configured to selectively connect the input member to an internal combustion engine;

first and second brake devices configured to selectively interconnect elements of the first and second differential gear sets, the transmission case, the input member, and the output member;

a first torque machine configured to transfer torque to the second differential gear set; and

a second torque machine configured to transfer torque to the first differential gear set.