Overrunning clutch and method of controlling engagement of same

• US 20070251748A1
• Filed: 05/01/2006
• Published: 11/01/2007
• Est. Priority Date: 05/01/2006
• Status: Active Grant

• Current Assignee: American AXLE & Manufacturing Incorporated (American AXLE & Manufacturing Holdings Incorporated)
• Original Assignee: American AXLE & Manufacturing Incorporated (American AXLE & Manufacturing Holdings Incorporated)
• Inventors: Downs, James, Degowske, Robert
• Granted Patent: US 7,363,995 B2
• Time in Patent Office: Days
• US Class Current: 180/243
• CPC Class Codes: B60K 17/043 Transmission unit disposed in on near the vehicle wheel, or between the differential gear unit and the wheel
• CPC Class Codes: B60K 17/26 characterised by arrangement, location, of type of freewheel device
• CPC Class Codes: B60K 2007/0038 the motor moving together with the wheel axle
• CPC Class Codes: B60K 2007/0061 the motor axle being parallel to the wheel axle
• CPC Class Codes: B60K 7/0007 the motor being electric
• CPC Class Codes: B60L 2220/46 Wheel motors, i.e. motor connected to only one wheel
• CPC Class Codes: F16D 2027/005 Details relating to the internal construction of coils or to clutches having more than one coil in the same housing
• CPC Class Codes: F16D 2500/1022 Electromagnet
• CPC Class Codes: F16D 2500/1064 Electric
• CPC Class Codes: F16D 2500/30406 Clutch slip
• CPC Class Codes: F16D 2500/70426 Clutch slip
• CPC Class Codes: F16D 27/11 with conical friction surfaces, e.g. cone clutches
• CPC Class Codes: F16D 48/064 Control of electrically or electromagnetically actuated clutches F16D48/062, F16D48/068 take precedence

Abstract

A suspension module with a suspension component, wheel hubs coupled to the suspension component, and a drive system. The drive system has a pair of units that selectively provide drive torque to an associated one of the wheel hubs. Each unit includes a motor, a first reduction gearset and an overrunning clutch. The first reduction gearset is disposed between the motor and its wheel hub and multiplies torque output from the motor. The clutch disconnects the motor from the associated wheel hub so that an output shaft of the motor is not drivingly coupled to the associated wheel hub when a rotational speed of the first portion does not exceed a rotational speed of the second portion. The clutch can be selectively operated to drivingly couple the motor to its wheel hub to permit the motor to be back-driven. A method for operating a hybrid power train is also provided.

Claims

1. A suspension module comprising:

at least one suspension component;

a pair of wheel hubs that are coupled to the at least one suspension component, each wheel hub being adapted to be mounted to a vehicle wheel; and

an auxiliary drive system having a pair of drive units, each drive unit being selectively operable for providing drive torque to an associated one of the wheel hubs, each drive unit including an electric motor, a first reduction gear set and a clutch, the first reduction gear set being disposed between the electric motor and the associated wheel hub and multiplying torque output from the electric motor, the clutch including;

a clutch housing;

an input member rotatably disposed in the clutch housing, the input member being drivingly coupled with an output shaft of the electric motor;

an output member rotatably disposed in the clutch housing, the output member being drivingly coupled with the associated one of the wheel hubs;

an engagement member that is threadably coupled to one of the input member and the output member and movable between a first position, wherein the engagement member is abutted against a first engagement surface to couple the input member and the output member for rotation with one another, a second position, wherein the engagement member is abutted against a second engagement surface to couple the input member and the output member for rotation with one another, and a neutral position, wherein the engagement member is spaced apart from both the first engagement surface and the second engagement surface;

a first spring disposed between the clutch housing and a first side of the engagement member, the first spring biasing the engagement member toward the first engagement surface;

a second spring disposed between the clutch housing and a second side of the engagement member, the second spring biasing the engagement member toward the second engagement surface;

an armature that is coupled to the first spring; and

a coil coupled to the clutch housing;

wherein the clutch is operable for connecting the electric motor with the associated wheel hub when a rotational speed of the input member exceeds a rotational speed of the output member; and

wherein the coil is selectively operable for moving the armature to compress the first spring to thereby move the engagement member into the first position when the rotational speed of the input member does not exceed a rotational speed of the output member.

2. The suspension module of claim 1, wherein the coil is mounted to the clutch housing.

3. The suspension module of claim 1, further comprising a controller coupled to the coil, the controller being operable for energizing and de-energizing the coil.

4. The suspension module of claim 3, wherein the controller is configured to operate the coil in a locked mode in which the coil is maintained in a continuously energized state.

5. The suspension module of claim 3, wherein the controller is configured to operate the coil in a semi-locked mode in which a state of the coil is dependent upon a value of a timer, a speed of the output member, a torque applied to the output member or combinations thereof.

6. The suspension module of claim 1, wherein each auxiliary drive system further includes a second reduction gear set disposed between the electric motor and the associated wheel hub.

7. The suspension module of claim 6, wherein the second reduction gear set includes an input gear, which is coupled for rotation with the second portion of the clutch, and a output gear which is coupled for rotation with the wheel hub.

8. The suspension module of claim 1, wherein the electric motor has an outer diameter that is less than about 8 inches.

9. The suspension module of claim 1, wherein the outer diameter is less than about 6 inches.

10. A method comprising:

providing a suspension module with at least one suspension component, a pair of wheel hubs and an auxiliary drive system, each wheel hub being coupled to the at least one suspension component and adapted to be mounted to a vehicle wheel, the auxiliary drive system having a pair of drive units, each drive unit including an electric motor, a first reduction gear set and a clutch, the first reduction gear set being disposed between the electric motor and the associated wheel hub and multiplying torque output from the electric motor, the clutch being disposed between the first reduction gear set and the wheel hub and having an input member, an output member, an engagement member and a coil assembly, the engagement member being threadably coupled to one of the input member and the output member and movable between a first position, wherein the engagement member is abutted against a first engagement surface to couple the input member and the output member for rotation with one another, and a neutral position, wherein the engagement member is spaced apart from the first engagement surface, the engagement member being biased into the neutral position and moving into the first position in response to rotation of the input member in a predetermined rotational direction at a rotational speed that exceeds a rotational speed of the output member; and

activating the coil assembly to place the engagement member in the first position when the input member is rotating in the predetermined direction and the rotational speed of the input member does not exceed the rotational speed of the output member to cause the electric motor to generate electricity.

11. The method of claim 10, wherein the coil assembly includes an armature and a coil that is configured to move the armature.

12. The method of claim 11, wherein activating the coil assembly includes maintaining the coil in a continuously energized state.

13. The method of claim 11, wherein activating the coil assembly includes maintaining the coil in an intermittently energized state that is comprised of an alternating series of first events, wherein the coil is maintained in a continuously energized state, and second events, wherein the coil is maintained in a continuously de-energized state.

14. The method of claim 13, wherein a duration of the first events is based upon a value of a timer, a speed of the output member, a torque applied to the output member or combinations thereof.

15. A method for operating an electrically-powered auxiliary power train comprising:

providing an electrically-powered auxiliary power train having an electric motor, a gear reduction unit, a clutch and a wheel hub that is adapted for mounting a vehicle wheel thereon, the motor being configured to selectively drive the wheel hub through the gear reduction unit and the clutch, the clutch being an overrunning clutch that de-couples the electric motor from the wheel hub when a rotational speed of the wheel hub exceeds a first predetermined speed;

identifying a braking event; and

locking the clutch to transmit rotary power between the wheel hub and the electric motor to cause the electric motor to generate electricity and slow the speed of the wheel hub when the rotational speed of the wheel hub exceeds the first predetermined speed and the braking event has been identified.

16. The method of claim 15, wherein the overrunning clutch is a cone clutch having an input member, an output member and an engagement member that is threadably coupled to the input member and axially translatable between a first position, in which drive torque is transmitted between the input member and the output member, and a second position, in which drive torque is not transmitted between the input member and the output member.

17. The method of claim 16, wherein a spring biases the engagement member toward the second position.

18. The method of claim 17, wherein the clutch includes a coil assembly, having an armature and a coil, and wherein locking the clutch includes activating the coil to move the armature and compress the spring.