Vehicle transmission with common carrier planetary gear set

Patent metadata

Field	Value
Publication number	US-9707834-B2
Application number	US-201414275950-A
Country	US
Kind code	B2
Filing date	May 13, 2014
Priority date	May 13, 2014
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A transmission with a common carrier planetary gear set is provided for a vehicle that has drive axle half shafts defining an axis of rotation, an electric motor/generator with a motor shaft parallel with the axis of rotation, either concentric with the axis of rotation or spaced therefrom, and a differential with a differential carrier connected with the drive axle half shafts. The planetary gear set has a first sun gear member continuously or selectively connectable with the motor shaft, first and second pinion gears, a carrier member rotatably supporting the first and the second pinion gears so that the first pinion gear meshes with the first sun gear member, and a ring gear member meshing with one of the pinion gears. The ring gear is connectable to a non-rotating housing. The carrier member is operatively connected with the differential carrier.

First claim

The invention claimed is:

1. A transmission for a vehicle, the vehicle including first and second drive axle half shafts rotatable about an axis of rotation, an electric motor/generator with a motor shaft parallel with the drive axle half shafts, and a differential with a differential carrier operatively connected with the drive axle half shafts, the transmission comprising:
a planetary gear set having:
a first sun gear member continuously connected or selectively connectable with the motor shaft;
a stepped pinion with first and second pinion gears coaxial with one another and permanently connected together to rotate in unison at a common speed;
a carrier member rotatably supporting the stepped pinion so that the first pinion gear meshes with the first sun gear member;
a second sun gear member meshing with the second pinion gear;
a first ring gear member meshing with one of the pinion gears; and
a second ring gear member meshing with the other one of the pinion gears;

a non-rotating housing radially surrounding the first and second ring gear members;
a first brake selectively engageable to ground the first ring gear member to the housing;
a second brake selectively engageable to ground the second ring gear member to the housing;
a first clutch selectively engageable to connect the motor shaft to rotate in unison with the first sun gear member; and
a second clutch selectively engageable to connect the motor shaft to rotate in unison with the second sun gear member,
wherein the carrier member is operatively connectable to the differential carrier, and the transmission is operable to establish five different forward ratios of torque of the carrier member to torque of the motor shaft by engaging the clutches and brakes in different combinations of two.

2. The transmission of claim 1 , wherein the first pinion gear is larger in diameter than the second pinion gear, and wherein the second ring gear member meshes with the second pinion gear.

3. The transmission of claim 1 , wherein the first pinion gear is larger in diameter than the second pinion gear, and wherein the first ring gear member meshes with the first pinion gear.

4. The transmission of claim 1 , wherein the first ring gear member meshes with the first pinion gear, and the second ring gear member meshes with the second pinion gear, and wherein one ratio of torque of the carrier member to torque of the motor shaft is established when only the first brake is engaged, and another ratio of torque of the carrier member to torque of the motor shaft is established when only the second brake is engaged.

5. The transmission of claim 1 , wherein the second ring gear member meshes with the second pinion gear; wherein the first sun gear is selectively connectable to the second sun gear to rotate in unison therewith, and wherein a first ratio of torque of the carrier member to torque of the motor shaft is established when only the first brake is engaged, and a lower second ratio of torque of the carrier member to torque of the motor shaft is established when only the second brake is engaged.

6. A transmission for a vehicle, the vehicle including first and second drive axle half shafts rotatable about an axis, an electric motor/generator with a motor shaft parallel with the drive axle half shafts, and a differential with a differential carrier operatively connected with the drive axle half shafts, the transmission comprising:
a planetary gear set having:
a first sun gear member continuously connected or selectively connectable with the motor shaft;
a stepped pinion with first and second pinion gears coaxial with one another and permanently connected together to rotate in unison at a common speed;
a carrier member operatively connectable to the differential carrier and rotatably supporting the stepped pinion such that the first pinion gear meshes with the first sun gear member; and
a first ring gear member meshing with one of the pinion gears; and

a non-rotating housing radially surrounding the ring gear member, the ring gear member being continuously connected or selectively connectable with the housing,
wherein the planetary gear set has a second sun gear member meshing with the second pinion gear, and wherein the planetary gear set has a second ring gear member meshing with the second pinion gear;
wherein the housing defines an internal cavity having a first predetermined diameter, wherein the planetary gear set is positioned within the internal cavity, and wherein the internal cavity houses a first selectively engageable brake engageable to ground the first ring gear member to the housing, and a second selectively engageable brake engageable to ground the second ring gear member to the housing; and
wherein the carrier member defines an interior space radially inward thereof, and wherein the interior space houses a first clutch selectively engageable to connect the motor shaft for rotation in unison with the first sun gear member, and a second clutch selectively engageable to connect the motor shaft for rotation in unison with the second sun gear member.

7. A powertrain for a vehicle, the vehicle having first and second drive axle half shafts establishing an axis of rotation about which both of the drive axle half shafts are rotatable, the powertrain comprising:
an electric motor/generator having a motor shaft parallel with the axis of rotation;
a transmission including:
a planetary gear set having:
a first sun gear member continuously connected or selectively connectable with the motor shaft;
a stepped pinion with first and second pinion gears coaxial with one another and permanently connected together to rotate in unison at a common speed;
a carrier member rotatably supporting the stepped pinion so that the first pinion gear meshes with the first sun gear member;
a second sun gear member meshing with the second pinion gear;
a first ring gear member meshing with one of the pinion gears; and
a second ring gear member meshing with the other one of the pinion gears;

a non-rotating housing radially surrounding the first and second ring gear members;
a first brake selectively engageable to ground the first ring gear member to the housing;
a second brake selectively engageable to ground the second ring gear member to the housing;
a first clutch selectively engageable to connect the motor shaft to rotate in unison with the first sun gear member; and
a second clutch selectively engageable to connect the motor shaft to rotate in unison with the second sun gear member, and

a differential having a differential carrier operatively connected to the carrier member and to the drive axle half shafts,
wherein the transmission is operable to establish five different forward ratios of torque of the carrier member to torque of the motor shaft by engaging the clutches and brakes in different combinations of two.

8. The powertrain of claim 7 , wherein the first pinion gear is larger in diameter than the second pinion gear, and wherein the second ring gear member meshes with the second pinion gear.

9. The powertrain of claim 7 , wherein the first pinion gear is larger in diameter than the second pinion gear, and wherein the first ring gear member meshes with the first pinion gear.

10. The powertrain of claim 7 , wherein the first ring gear member meshes with the first pinion gear, and the second ring gear member meshes with the second pinion gear; and wherein one ratio of torque of the carrier member to torque of the motor shaft is established when only the first brake is engaged, and another ratio of torque of the carrier member to torque of the motor shaft is established when only the second brake is engaged.

11. The powertrai

Assignees

• Gm Global Tech Operations Llc

Inventors

• Lee Chi Teck
• Mcgrew Jr Arthur L

Classifications

• F16H3/66

  composed of a number of gear trains without drive passing from one train to another · CPC title

• F16H1/36

  with two central gears coupled by intermeshing orbital gears · CPC title

• F16H2200/0047

  the gear ratios comprising five forward speeds · CPC title

• F16H2200/2007

  with two sets of orbital gears · CPC title

• F16H2200/2041

  with four engaging means · CPC title