Transmission arrangements for hybrid electric vehicles

• US 7,128,677 B2
• Filed: 02/13/2006
• Issued: 10/31/2006
• Est. Priority Date: 05/03/2001
• Status: Expired due to Term

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Kozarekar, Shailesh, Supina, Joseph
• Primary Examiner(s): ESTREMSKY, SHERRY LYNN
• Application Number:
  US11/276,061
• Publication Number:
  US 20060116231A1
• Time in Patent Office: 260 Days
• Field of Search: 475/5, 180/65.2, 180/65.6
• US Class Current: 475/5
• 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 6/40 characterised by the assembly or relative disposition of components
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60K 6/448 Electrical distribution type
• CPC Class Codes: B60K 6/54 Transmission for changing ratio
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 2240/44 related to combustion engines
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60L 2240/507 Operating parameters
• CPC Class Codes: B60L 2260/26 Transition between different drive modes
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/30 Control strategies involving selection of transmission gear ratio control of change speed gearings, together with other vehicle sub-units B60W10/10; HEV transmission gearing B60K6/36; gearings and control thereof F16H
• CPC Class Codes: B60W 20/40 Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers power-up or power-down of the driveline B60W30/192
• CPC Class Codes: B60W 30/18027 Drive off, accelerating from standstill
• CPC Class Codes: F16H 2037/0866 Power split variators with distributing differentials, with the output of the CVT connected or connectable to the output shaft
• CPC Class Codes: F16H 2200/0034 : the gear ratios comprising two forward speeds
• CPC Class Codes: F16H 2200/2005 : with one sets of orbital gears
• CPC Class Codes: F16H 2200/2007 : with two sets of orbital gears
• CPC Class Codes: F16H 3/725 : with means to change ratio in the mechanical gearing
• CPC Class Codes: F16H 3/727 : with at least two dynamo electric machines for creating an electric power path inside the gearing, e.g. using generator and motor for a variable power torque path special adapted for a hybrid electric vehicle B60K6/20
• CPC Class Codes: F16H 3/728 : with means to change ratio in the mechanical gearing
• CPC Class Codes: F16H 37/046 : with an additional planetary gear train, e.g. creep gear, overdrive
• CPC Class Codes: F16H 57/0439 : using multiple pumps with different power sources or a single pump with different power sources, e.g. one and the same pump may selectively be driven by either the engine or an electric motor
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility

Abstract

A geared, power transmission mechanism for a hybrid electric vehicle wherein multiple power flow paths are established between an engine and vehicle traction wheels and between an electric motor and the vehicle traction wheels. At least one of the power flow paths is characterized by at least two ratios.

Claims

1. A powertrain for a hybrid electric vehicle having an engine, an electric generator and an electric motor acting as a pair of drive power sources for driving vehicle traction wheels, the powertrain comprising:

gear elements drivably connecting the pair of power sources to the traction wheels through first and second geared power flow paths, at least one geared power flow path having at least two gear ratios;

one of the pair of drive power sources being connected by the gear elements to the traction wheels through the first geared power flow path;

the first geared power flow path comprising a first planetary gear unit, the first planetary gear unit having a sun gear connected to the generator, a carrier connected to the engine and a ring gear connected drivably to one gear element of a second planetary gear unit;

the engine defining one power source on an engine axis and the motor defining in part another power source on a motor axis; and

a friction element sub-assembly for the second planetary gear unit establishing selectively each of the gear ratios;

the motor being connected drivably to the traction wheels through fixed ratio gear elements and a second gear element of the second planetary gear unit being connected drivably to the traction wheels to complement motor driving power.

2. The powertrain set forth in claim 1 wherein the first planetary gear unit is disposed on the engine axis and the second planetary gear unit is disposed on an axis that is offset from and parallel to the engine axis.

3. A powertrain for a hybrid electric vehicle having an engine, an electric generator and an electric motor acting as a pair of drive power sources for driving vehicle traction wheels, the powertrain comprising:

gear elements drivably connecting the pair of power sources to the traction wheels through first and second geared power flow paths, at least one geared power flow path having at least two gear ratios;

one of the pair of drive power sources being connected by the gear elements to the traction wheels through the first geared power flow path;

the first geared power flow path comprising a first planetary gear unit, the first planetary gear unit having a sun gear connected to the generator, a carrier connected to the engine and a ring gear connected drivably to a second planetary gear unit;

the engine defining one power source on an engine axis and the motor defining in part another power source on a motor axis common to the engine axis;

a friction element sub-assembly for the second planetary gear unit establishing selectively each of the gear ratios; and

the motor being connected drivably to the traction wheels through the second planetary gear unit, the engine being connected drivably to the traction wheels to complement motor driving power;

wherein the first planetary gear unit and the second planetary gear unit are disposed on the common axis for the motor and the engine axis.

4. The powertrain set forth in claim 3 wherein the vehicle traction wheels are rear traction wheels, the gear elements defining a rear wheel drive powertrain configuration.

5. A powertrain for a hybrid electric vehicle having an engine, an electric generator and an electric motor, the powertrain comprising:

a first planetary gear unit on an axis that is common to an engine axis, the engine being connected drivably to a torque input element of the first planetary gear unit;

a second planetary gear unit on a countershaft axis spaced from and parallel to both the engine axis and an electric motor axis, a torque output element of the second planetary gear element being connected drivably to vehicle traction wheels;

a torque input element of the second planetary gear unit being connected drivably to the motor and a torque output element of the first planetary gear unit; and

a friction element sub-assembly for establishing and disestablishing each of two gear ratios in the second gear unit, whereby a ratio change occurs in power flow paths for the motor and the engine.

6. A powertrain for a hybrid electric vehicle having an engine, an electric generator, and an electric motor, the powertrain comprising:

a planetary gear unit on an engine axis, the engine being connected drivably to a first element of the planetary gear unit, the generator being connected drivably to a second element of the planetary gear unit;

two countershaft gear elements mounted on a countershaft axis spaced from and parallel to a motor axis and the engine axis;

a countershaft clutch assembly for establishing and disestablishing each of two gear ratios in the countershaft gearing;

the countershaft clutch assembly selectively connecting each countershaft gear element to vehicle traction wheels, the motor being drivably connected through the countershaft clutch assembly to the countershaft gear elements; and

a torque output element of the planetary gear unit being drivably connected to the countershaft gear elements through the countershaft clutch assembly.

7. A powertrain for a hybrid electric vehicle having an engine, an electric generator, and an electric motor, the powertrain comprising:

a planetary gear unit on an engine axis;

the engine being connected drivably to a first element of the planetary gear unit, the generator being connected drivably to a second element of the planetary gear unit;

countershaft gearing comprising at least two countershaft gear elements mounted on a countershaft axis spaced from and parallel to a motor axis and the engine axis;

countershaft clutches for selectively connecting each of the countershaft gear elements to vehicle traction wheels;

the motor being drivably connected through the countershaft clutches to the countershaft gears; and

a torque output element of the planetary gear unit being drivably connected to the counter shaft gearing through the countershaft clutches.

8. The powertrain set forth in claim 7 wherein the countershaft clutches comprise multiple clutch elements in each of two power flow paths from the engine and the motor, whereby engine power is available to complement motor power during a gear ratio change in the power flow path for the motor and motor power is available to complement engine power during a gear ratio change in the power flow path for the engine, thus effecting smooth gear ratio changes in the powertrain.

9. A powertrain for a hybrid electric vehicle having an engine, an electric generator and an electric motor, the powertrain comprising:

a first planetary gear unit on an axis that is common to an engine axis, the engine being connected drivably to a torque input element of the first planetary gear unit, the first planetary gear unit defining a first power flow path for the engine for driving vehicle traction wheels; and

a second planetary gear unit with a friction element sub-assembly for establishing and disestablishing each of two gear ratios in a second power flow path for the motor for driving the vehicle traction wheels.

10. The powertrain set forth in claim 9 wherein the vehicle is a rear wheel drive vehicle, the geared connection defining the second power flow path being disposed on an axis that is common to axes for the engine and the motor.

11. The powertrain set forth in claim 9 wherein the second planetary gear unit is located on a countershaft axis spaced from and parallel to the engine axis and a motor axis.

12. The powertrain set forth in claim 9 wherein the second planetary gear unit is located on a motor axis spaced from and parallel to the engine axis.

13. The powertrain set forth in claim 12 including countershaft gearing forming in part the first and second power flow paths.

14. A powertrain for a hybrid electric vehicle having an engine, an electric generator and an electric motor, the powertrain comprising:

a first planetary gear unit on an axis that is common to an engine axis, the engine being connected drivably to a first element of the first planetary gear unit,

the electric generator being connected to a second element of the first planetary gear unit, a third element of the first planetary gear unit being drivably connected to vehicle traction wheels;

the first planetary gear unit defining a first power flow path for the engine for driving the vehicle traction wheels; and

a second planetary gear sub-assembly for establishing and disestablishing each of two gear ratios in a second power flow path for the motor for driving the vehicle traction wheels.

15. The powertrain set forth in claim 14 wherein the first element of the first planetary gear unit is a planetary carrier, the second element of the first planetary gear unit is a sun gear and the third element of the first planetary gear unit is a ring gear.