HYBRID POWERTRAIN WITH MECHATRONIC ACTUATOR ASSEMBLY AND METHOD OF CONTROLLING THE SAME

• US 20160185335A1
• Filed: 12/30/2014
• Published: 06/30/2016
• Est. Priority Date: 12/30/2014
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Namuduri, Chandra S., Rajala, Alexandru, Holmes, Alan G., Nehl, Thomas Wolfgang, Atluri, Venkata Prasad, Raghavan, Madhusudan
• Granted Patent: US 9,481,357 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60K 2006/268 Electric drive motor starts the engine, i.e. used as starter motor
• CPC Class Codes: B60K 2006/4841 the gear provides shifting between multiple ratios
• CPC Class Codes: B60K 6/36 characterised by the transmission gearings
• CPC Class Codes: B60K 6/387 Actuated clutches, i.e. clutches engaged or disengaged by electric, hydraulic or mechanical actuating means
• CPC Class Codes: B60K 6/44 Series-parallel type
• CPC Class Codes: B60K 6/485 Motor-assist type
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: B60W 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• 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: F16H 19/02 for interconverting rotary or oscillating motion and reciprocating motion
• CPC Class Codes: F16H 7/0827 for disconnecting the drive
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/93 Conjoint control of different elements

Abstract

A powertrain includes an engine with a crankshaft rotating on a first axis, motor/generator unit (MGU), belted drive system, transmission, actuator assembly, and controller. An MGU rotor shaft rotates about a second axis. The belted drive assembly has a first pulley connected to the crankshaft, a second pulley selectively connected to the rotor shaft, and an endless rotatable drive element that connects the pulleys. The transmission is connected to the flywheel via an input clutch. The actuator assembly has a third axis parallel to the first and second axes, a linear actuator(s), pinion gears translatable along the third axis to selectively engage the first and second gear elements, and overrunning clutches to passively disengage the pinion gears from the first or second gear element. The controller transmits control signals to the MGU and linear actuators to command a control state via translation of the pinion gears.

Claims

1. A hybrid powertrain comprising:

an engine having a crankshaft, a flywheel connected to and rotatable via the crankshaft, and a first gear element that rotates in conjunction with the flywheel about a first axis;

a motor-generator unit (MGU) having a rotor shaft that is rotatable about a second axis that is parallel to the first axis, and a second gear element connected to the rotor shaft;

a selective coupling device disposed between the crankshaft and the MGU;

a belted drive assembly having a first pulley connected to the crankshaft, a second pulley connected to the rotor shaft, and an endless rotatable drive element that connects the first and second pulleys, wherein an engagement of the selective coupling device delivers motor torque from the MGU to the crankshaft;

a transmission operably connected to the engine via an input clutch;

a mechatronic actuator assembly disposed between the first and second gear elements, and having a third axis that is parallel to the first and second axes, at least one linear actuator, a pair of pinion gears translatable along the third axis to selectively engage a respective one of the first and second gear elements, and a first overrunning clutch configured to passively disengage one of the pinion gears from the first gear element when a speed of the crankshaft exceeds a speed of the MGU; and

a controller programmed to process a set of control inputs to thereby determine a required control state of the powertrain, and to transmit control signals to the MGU and the at least one linear actuator to thereby command execution of the required control state via translation of at least one of the pinion gears along the third axis.

2. The hybrid powertrain of claim 1, wherein the mechatronic actuator assembly also includes a second overrunning clutch configured to disengage the other pinion gear of the pair of pinion gears from the second gear element when the speed of the crankshaft exceeds the speed of the MGU.

3. The hybrid powertrain of claim 1, wherein the at least one linear actuator includes a pair of linear actuators arranged on a respective fourth and fifth axis.

4. The hybrid powertrain of claim 1, wherein the at least one linear actuator includes a pair of linear actuators coaxially arranged on a fourth axis.

5. The hybrid powertrain of claim 1, wherein the at least one linear actuator includes a single linear actuator arranged on a fourth axis that is parallel to the third axis.

6. The hybrid powertrain of claim 1, wherein the at least one linear actuator is selected from the group consisting of a solenoid device, a rotary ball screw device, and a shape-memory alloy device.

7. The hybrid powertrain of claim 1, wherein each of the at least one linear actuators includes a plunger that translates toward the first gear element along a fourth axis when the at least one linear actuator is activated, and the actuator assembly includes a plurality of lever forks, at least one of which is operatively connected to the plunger to transmit an axial force to the pinion gears along the third axis when the plunger translates toward the first gear element.

8. The hybrid powertrain of claim 1, further comprising a free plunger having two distal ends, wherein the two distal ends are each engaged by a different one of the plurality of lever forks.

9. The hybrid powertrain of claim 1, wherein the pinion gear that is engagable with the second gear element is nested within a larger gear element to form a matched gear.

10. A mechatronic actuator assembly for a system having a first gear element rotatable about a first axis and a second gear element rotatable about a second axis, the mechatronic actuator assembly comprising:

at least one linear actuator responsive to a set of control signals from a controller to generate an axial force;

a pair of pinion gears that are translatable along a third axis that is parallel to the first and second axes in response to the axial force from the at least one linear actuator, wherein translation of the pair of pinion gears along the third axis results in engagement by the pair of pinion gears of a respective one of the first and second gear elements; and

a first overrunning clutch configured to passively disengage one of the pair of pinion gears from the first gear element when a speed of the first gear element exceeds a speed of the second gear element.

11. The actuator assembly of claim 10, further comprising a second overrunning clutch configured to passively disengage the other pinion gear of the pair of pinion gears from the second gear element when a speed of the first gear element exceeds a speed of the second gear element.

12. The actuator assembly of claim 10, wherein the second gear element is connected to and driven by a motor/generator unit (MGU), the actuator assembly further comprising a controller programmed to process control inputs to thereby determine a control state of the actuator assembly, and to transmit control signals to the MGU and the at least one linear actuator to thereby command execution of the determined control state via translation of at least one of the pinion gears along the third axis.

13. The actuator assembly of claim 10, wherein the at least one linear actuator is a single linear actuator arranged on a fourth axis that is parallel to the first, second, and third axes.

14. The actuator assembly of claim 10, wherein the at least one linear actuator is a pair of linear actuators arranged on a respective fourth and fifth axis.

15. The actuator assembly of claim 10, wherein each of the at least one linear actuators includes a plunger that translates toward the first gear element along a fourth axis that is parallel to the first, second, and third axes when the at least one linear actuator is activated, and the actuator assembly includes a plurality of lever forks at least one of which is operatively connected to the plunger to transmit an axial force to the pinion gears along the third axis when the plunger translates toward the first gear element.

16. The actuator assembly of claim 10, further comprising a free plunger having two distal ends, wherein the two distal ends are each engaged by a different one of the plurality of lever forks.

17. The actuator assembly of claim 10, wherein the pinion gear that is engagable with the second gear element is nested within a larger gear element to form a matched gear.

18. A method for control of a mechatronic actuator assembly aboard a vehicle having a hybrid powertrain that includes an engine with a crankshaft, a flywheel connected to and rotatable via the crankshaft, a first gear element that rotates in conjunction with the flywheel about a first axis, and a motor-generator unit (MGU) having a rotor shaft that is rotatable about a second axis that is parallel to the first axis and a second gear element connected to the rotor shaft, and a belted drive assembly having a first pulley connected to the crankshaft, a second pulley connected to the rotor shaft, and an endless rotatable drive element that connects the first and second pulleys to thereby deliver motor torque from the MGU to the crankshaft, the method comprising:

providing the mechatronic actuator assembly between the first and second gear elements, wherein the mechatronic actuator assembly includes at least one linear actuator;

receiving, via a controller, a set of control inputs;

determining if the set of control inputs is indicative of a required control state of the powertrain in which there is a need to start the engine via the MGU in either a belt-assisted start via the first and second pulleys and the second gear element via engagement a selective coupling device disposed between the crankshaft and the MGU, or a geared start via the first gear element;

energizing the least one linear actuator to thereby generate an axial force along a third axis that is parallel to the first and second axes;

translating, via the axial force, a pair of pinion gears along the third axis to selectively engage a respective one of the first and second gear elements when the set of control inputs is indicative of the need to start the engine, including transmitting a control signal to the at least one linear actuator to cause the translating of the pinion gears to occur; and

passively disengaging the pair of pinion gears from a respective one of the first and second gear elements via at least one overrunning clutch when a speed of the crankshaft exceeds a speed of the MGU.

19. The method of claim 18, wherein transmitting a control signal to at least one linear actuator includes transmitting the control signal to a single linear actuator arranged on a fourth axis.

20. The method of claim 18, wherein transmitting a control signal to at least one linear actuator includes transmitting the control signal to a pair of linear actuators arranged on a respective fourth and fifth axis.