Two-speed transmission for electric vehicle

Patent metadata

Field	Value
Publication number	US-9242555-B2
Application number	US-201314010672-A
Country	US
Kind code	B2
Filing date	Aug 27, 2013
Priority date	Nov 20, 2007
Publication date	Jan 26, 2016
Grant date	Jan 26, 2016

Abstract

A transmission to transfer power from an electric motor to first and second axles of a vehicle includes an input shaft adapted to be driven by the electric motor and a first planetary gear set. A second planetary gear set has a first member driven by the first planetary gear set, a second member restricted from rotation and a third member. A differential assembly has a first side gear adapted to drive the first axle, a second side gear adapted to drive the second axle and a pair of pinion gears meshed with the first and second side gears. A first clutch is operable to drivingly interconnect the first member and the differential assembly. A second clutch is operable to drivingly interconnect the third member and the differential assembly.

First claim

What is claimed is:

1. A transmission for transferring rotary power from an electric motor to a pair of primary wheels rotatable about a first rotary axis and a pair of secondary wheels rotatable about a second rotary axis in a motor vehicle, the transmission comprising:
an input shaft adapted to be driven by the electric motor about a third rotary axis generally parallel to and offset from the first rotary axis and the second rotary axis;
a first planetary gear set having an input driven by said input shaft and an output driven at a reduced speed relative to said input;
a second planetary gear set having a first member driven by said output of said first planetary gear set, a second member restricted from rotation, and a third member;
a differential assembly aligned for rotation about the first rotary axis, said differential assembly having a differential input, a first differential output driving one of the primary wheels, and a second differential output driving the other one of the primary wheels;
a drive shaft driven by said second planetary gear set and aligned for rotation about said third rotary axis;
a transfer assembly drivingly connecting said differential input for rotation with said drive shaft;
a first clutch operable for selectively coupling said first member and said drive shaft;
a second clutch operable for selectively coupling said third member and said drive shaft; and
a driveline coupling said drive shaft to the pair of secondary wheels, said driveline including a propeller shaft aligned for rotation about a fourth rotary axis transverse to the first rotary axis and the second rotary axis and said third rotary axis.

2. The transmission of claim 1 wherein said first member of said second planetary gear set is a ring gear, said second member is a non-rotary sun gear, and said third member is a carrier, wherein said second planetary gear set further includes planet gears rotatably supported by said carrier and which are meshed with said ring gear and said sun gear.

3. The transmission of claim 1 wherein said transfer assembly includes a first transfer member fixed for rotation with said drive shaft, a second transfer member fixed for rotation with said differential input, and a drive member operable for drivingly interconnecting said second transfer member to said first transfer member, wherein said first clutch is operable for selectively coupling said ring gear to said first transfer member and define a first speed ratio drive connection between said output of said first planetary gear set and said differential input, and wherein said second clutch is operable for selectively coupling said carrier to said first transfer member and define a second speed ratio drive connection between said output of said first planetary gear set and said differential input.

4. The transmission of claim 3 wherein said transfer assembly provides a speed reduction between said first transfer member and said second transfer member.

5. The transmission of claim 3 wherein said first transfer member of said transfer assembly is a drive sprocket and said transfer member is a driven sprocket and said drive member is a chain assembly for drivingly interconnecting said drive sprocket and said driven sprocket.

6. The transmission of claim 1 wherein said first member of said second planetary gear set is a ring gear, said second member is a non-rotary sun gear, and said third member is a planet carrier rotatably supporting planet gears which are meshed with said ring gear and said non-rotary sun gear, wherein said first clutch is operable for selectively coupling said ring gear to said drive shaft for establishing a first speed ratio drive connection between said output of said first planetary gear set and said differential input, and wherein said second clutch is operable for selectively coupling said planet carrier to said drive shaft for establishing a second speed ratio drive connection between said output of said first planetary gear set and said differential input.

7. The transmission of claim 6 wherein said driveline includes a third gear set drivingly interconnecting said drive shaft to said propeller shaft for driving the pair of secondary wheels, said third gear set including a pinion gear fixed for rotation about said third rotary axis with said drive shaft and a ring gear aligned for rotation about said fourth rotary axis in meshed engagement with said pinion gear and attached to said propeller shaft for driving the pair of secondary wheels.

8. A transmission for transferring rotary power from an electric motor to a pair of primary wheels rotatable about a first rotary axis and a pair of secondary wheels rotatable about a second rotary axis in a motor vehicle, the transmission comprising:
an input shaft adapted to be driven by the electric motor about a third rotary axis generally parallel to and offset from the first rotary axis and the second rotary axis;
a first planetary gear set including a first sun gear driven by said input shaft, a non-rotary first ring gear, a first carrier, and a plurality of first planet gears rotatably supported by said first carrier and which are meshed with said first sun gear and said non-rotary first ring gear;
a second planetary gear set including a second ring gear driven by said first carrier, a non-rotary second sun gear, a second carrier, and a plurality of second planet gears rotatably supported by said second carrier and which are meshed with said second ring gear and said non-rotary second sun gear;
a differential assembly aligned for rotation about the first rotary axis, said differential assembly having a differential input, a first differential output driving one of the primary wheels, and a second differential output driving the other one of the primary wheels;
a drive shaft driven by at least one of said second carrier and said second ring gear of said second planetary gear set and aligned for rotation about said third rotary axis;
a first clutch operable for selectively coupling said drive shaft for rotation with said second ring gear;
a second clutch operable for selectively coupling said drive shaft for rotation with said second carrier; and
a driveline coupling said drive shaft to the pair of secondary wheels, said driveline including a propeller shaft aligned for rotation about a fourth rotary axis transverse to the first rotary axis and the second rotary axis and said third rotary axis.

9. The transmission of claim 8 further comprising a transfer assembly interconnecting said drive shaft to said differential input, wherein said first clutch is operable for selectively coupling said second ring gear to said drive shaft to establish a first speed ratio drive connection between said input shaft and said differential assembly, and wherein said second clutch is operable for selectively coupling said second carrier to said drive shaft to establish a second speed ratio drive connection between said input shaft and said differential assembly.

10. The transmission of claim 9 wherein said transfer assembly includes a first sprocket driven by said drive shaft, a second sprocket driving said differential input, and a drive member drivingly interconnecting said first and second sprockets.

11. The transmission of claim 9 wherein said driveline includes a third gear set drivingly interconnecting said drive shaft to said propeller shaft for driving the pair of secondary wheels, wherein said first clutch is operable for selectively coupling said second ring gear to said drive shaft to establish a first speed ratio drive connection between said input shaft and said propeller shaft, and wherein said second clutch is operable for selectively coupling said

Assignees

• Magna Powertrain Usa Inc

Inventors

• Wenthen David W

Classifications

• B60K17/342 Primary

  having a longitudinal, endless element, e.g. belt or chain, for transmitting drive to wheels · CPC title

• B60K1/00

  Arrangement or mounting of electrical propulsion units (B60K7/00 takes precedence; arrangement or mounting of plural diverse prime-movers for mutual or common propulsion B60K6/00) · CPC title

• F16H2200/2097

  comprising an orbital gear set member permanently connected to the housing, e.g. a sun wheel permanently connected to the housing · CPC title

• F16H2200/2007

  with two sets of orbital gears · CPC title

• F16H3/64

  composed of a number of gear trains, the drive always passing through all the trains, each train having not more than one connection for driving another train · CPC title