POWER TRANSMITTING COMPONENT WITH TWIN-FORK ACTUATOR

• US 20150053027A1
• Filed: 08/15/2014
• Published: 02/26/2015
• Est. Priority Date: 08/23/2013
• 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 P.
• Granted Patent: US 9,500,237 B2
• Time in Patent Office: Days
• US Class Current: 74/15.4
• CPC Class Codes: B60K 17/344 having a transfer gear
• CPC Class Codes: B60K 17/3467 combined with a change speed gearing, e.g. range gear
• CPC Class Codes: B60K 17/35 including arrangements for suppressing or influencing the power transfer, e.g. viscous clutches differential gearing with locking devices F16H48/20
• CPC Class Codes: B60K 2023/0858 with electric means, e.g. electro-hydraulic means
• CPC Class Codes: B60K 23/08 for changing number of driven wheels , for switching from driving one axle to driving two or more axles B60K17/3515 takes precedence
• CPC Class Codes: B60K 23/0808 for varying torque distribution between driven axles, e.g. by transfer clutch
• CPC Class Codes: B60K 25/06 from the transmission power take-off transmissions having power-take-off B60K17/28
• CPC Class Codes: B60Y 2400/3012 using Hall effect
• CPC Class Codes: B60Y 2400/405 Electric motors actuators
• CPC Class Codes: B60Y 2400/412 Screw-nut mechanisms
• CPC Class Codes: B60Y 2400/82 Four wheel drive systems
• CPC Class Codes: F16D 13/58 Details tools for assembling or disassembling clutches B25B27/0064
• CPC Class Codes: F16D 23/12 Mechanical clutch-actuating mechanisms arranged outside the clutch as such specific for combined clutches F16D21/00; mechanisms specific for synchronisation F16D23/02
• CPC Class Codes: F16H 1/00 Toothed gearings for conveying rotary motion specific for conveying rotary motion with variable gear ratio or for reversing rotary motion F16H3/00
• CPC Class Codes: F16H 2063/3063 using screw devices
• CPC Class Codes: F16H 25/20 Screw mechanisms with automatic reversal F16H25/12
• CPC Class Codes: F16H 25/2015 Means specially adapted for stopping actuators in the end position; Position sensing means
• CPC Class Codes: F16H 59/70 dependent on the ratio established
• CPC Class Codes: F16H 63/304 the final output mechanisms comprising elements moved by electrical or magnetic force band brake actuating mechanisms F16H63/3003

Abstract

A power transmitting component having a actuator with a lead screw, which is driven by a motor and a transmission, a pusher assembly driven by the lead screw, and first and second clutch forks. Translation of the pusher coordinates movement of the first and second clutch forks along respective axes.

Claims

1. A power transmitting component comprising:

an actuator housing;

a motor coupled to the actuator housing;

a transmission driven by the motor, the transmission being at least partially housed in the actuator housing;

a lead screw that is rotatable about a first axis, the lead screw being driven by the transmission;

a first rail extending along a second axis that is generally parallel to the first axis;

a second rail extending along a third axis that is generally parallel to the first axis;

a cradle assembly driven by the lead screw axially along the first axis, the cradle assembly comprising a cradle having a first cradle yoke, which is slidably received on the first rail, and a second cradle yoke that is slidably received on the second rail;

a first clutch fork slidably mounted on the first rail; and

a second clutch fork slidably mounted on the second rail;

wherein movement of the cradle along the first rail coordinates movement of the first clutch fork along the second axis and movement of the second clutch fork along the third axis.

2. The power transmitting component of claim 1, wherein the first clutch fork comprises a first clutch fork yoke that is slidably mounted to the first rail and wherein a first spring is disposed between the first cradle yoke and the first clutch fork yoke.

3. The power transmitting component of claim 2, wherein the first spring is received coaxially on the first rail.

4. The power transmitting component of claim 2, wherein the second clutch fork comprises a second clutch fork yoke that is slidably mounted to the second rail and wherein a second spring is disposed between the second cradle yoke and the second clutch fork yoke.

5. The power transmitting component of claim 4, wherein the second spring is received coaxially on the second rail.

6. The power transmitting component of claim 4, wherein the first clutch fork is movable between a first fork position and a second fork position, and wherein the cradle comprises a first drive lug that is configured to contact a second drive lug formed on the first clutch fork to drive the first clutch fork in a first axial direction to drive the first clutch fork out of the first fork position and toward the second fork position.

7. The power transmitting component of claim 1, further comprising a first sensor target and a first sensor, the first sensor target being coupled to the first clutch fork for movement therewith, the first sensor being coupled to the actuator housing and configured to sense the first sensor target and responsively produce at least one first sensor signal that is indicative of a location of the first clutch fork along the second axis.

8. The power transmitting component of claim 7, wherein the first sensor comprises a plurality of Hall-effect sensors that are spaced apart along a first sensor axis that is parallel to the second axis.

9. The power transmitting component of claim 7, further comprising a second sensor target and a second sensor, the second sensor target being coupled to the second clutch fork for movement therewith, the second sensor being coupled to the actuator housing and configured to sense the second sensor target and responsively produce at least one second sensor signal that is indicative of a location of the second clutch fork along the third axis.

10. The power transmitting component of claim 9, wherein the second sensor comprises a plurality of Hall-effect sensors that are spaced apart along a sensor axis that is parallel to the third axis.

11. The power transmitting component of claim 1, wherein the cradle assembly further comprises a cradle body and a cradle spring, the cradle body being received in the cradle and threadably coupled to the lead screw, the cradle spring resiliently coupling the cradle body to the cradle.

12. The power transmitting component of claim 1, wherein the transmission comprises a gear train, the gear train having an input pinion, which is coupled to an output shaft of the motor for rotation therewith, and an output pinion that is coupled to the lead screw for common rotation.

13. A method for operating a power transmitting component, the power transmitting component having a first power transmitting member, a second power transmitting member and a collar, the first and second power transmitting members being rotatable along an axis, the collar being rotatably and slidably mounted to the first power transmitting member, the collar being axially movable along the axis between a fully disengaged position, in which the collar is disengaged from the second power transmitting member, and a fully engaged position, the method comprising:

providing an actuator with an electric motor and a clutch fork that is driven by the electric motor, the clutch fork being engaged to the collar;

translating the collar to the fully disengaged position;

generating a command to move the clutch fork to the engaged position and responsively operating the electric motor to cause the clutch fork to move the collar toward the fully engaged position;

determining a position of the collar along the axis after the electric motor has halted operation; and

limiting rotary power transmitted through the collar if the collar is not located in the fully engaged but is nevertheless engaged to the second power transmitting member to at least a predetermined extent.

14. The method of claim 13, further comprising inhibiting transmission of rotary power through the collar if the collar is not in the fully disengaged position and the collar is engaged to the second power transmitting member to an extent that is less than the predetermined extent.

15. A power transmitting component comprising:

a power take-off unit having a mode clutch and a multi-speed transmission, the mode clutch having a mode member that is axially movable along a transmission axis between a first mode position, in which no rotary power is transmitted through the mode clutch, and a second mode position in which rotary power is transmitted through the mode clutch, the multi-speed transmission having a transmission member that is movable along the transmission axis between a first transmission position, in which the transmission operates in a first gear ratio, and a second transmission position in which the transmission operates in a second, different gear ratio; and

an actuator having an actuator housing, a motor coupled to the actuator housing, an actuator transmission, a lead screw, a first rail, a second rail, a cradle assembly, a first clutch fork, a second clutch fork, a first fork spring and a second fork spring, the actuator transmission being driven by the motor and at least partially housed in the actuator housing, the lead screw being driven by the actuator transmission for rotation about a first axis, the first rail extending along a second axis that is generally parallel to the first axis, the second rail extending along a third axis that is generally parallel to the first axis, the cradle assembly

comprising a cradle, a cradle body, and a cradle spring, the cradle defining a first cradle yoke, which is slidably mounted on the first rail, a second cradle yoke, which is slidably mounted on the second rail, a first drive lug and a pair of arms, the cradle body being threadably coupled to the lead screw such that rotation of the lead screw causes corresponding axial movement of the cradle body along the first axis, the cradle spring being configured to center the cradle body between the arms of the cradle and to permit movement of the cradle body relative to the cradle along the first axis, the first clutch fork having a first clutch fork yoke, which is slidably mounted on the first rail, and a second drive lug, the first clutch fork being engaged to one of the mode member and the transmission member such that movement of the first clutch fork along the second axis causes corresponding movement of the one of the mode member and the transmission member along the transmission axis, the second clutch fork having a second clutch fork yoke, which is slidably mounted on the second rail, and a third drive lug, the second clutch fork being engaged to the other one of the mode member and the transmission member such that movement of the second clutch fork along the third axis causes corresponding movement of the other one of the mode member and the transmission member along the transmission axis, the first fork spring being received on the first rail and biasing the first clutch fork and the first cradle yoke apart from one another, the second fork spring being received on the second rail and biasing the second clutch fork and the second cradle yoke apart from one another;

wherein the first clutch fork is movable between a first fork position and a second fork position, wherein the second clutch fork is movable between a third fork position and a fourth fork position, wherein the first and second drive lugs contact one another over at least a portion of the travel of the first clutch fork when the first clutch fork is moved from the first fork position to the second fork position, and wherein the third drive lug contacts the actuator housing when the second clutch fork is in the fourth fork position.

16. The power transmitting component of claim 15, wherein the cradle body comprises a body member and a pair of guides, the body member defining a pair of guide slots and having a body structure and a pair of flanges coupled to opposite ends of the body structure, each of the flanges being movable through a flange aperture formed in a corresponding one of the arms in the cradle, each of the guides being mounted to the arms and received in a corresponding one of the guide slots, the guides cooperating with the cradle and the body member to mount the body member to the cradle in a manner that limits movement of the body member relative to the cradle to only axial movement along the first axis.

17. The power transmitting component of claim 15, wherein the second clutch fork comprises a third fork yoke that is slidably mounted on the second rail such that the second cradle yoke is disposed between the second and third fork yokes, and wherein the second cradle yoke contacts the third fork yoke over at least a portion of the travel of the second clutch fork when the second clutch fork is moved from the fourth fork position to the third fork position.

18. The power transmitting component of claim 15, further comprising a first sensor target, a first sensor, a second sensor target, and a second sensor, the first sensor target being coupled to the first clutch fork for movement therewith, the first sensor being coupled to the actuator housing and configured to sense the first sensor target and responsively produce at least one first sensor signal that is indicative of a location of the first clutch fork along the transmission axis, the second sensor target being coupled to the second clutch fork for movement therewith, the second sensor being coupled to the actuator housing and configured to sense the second sensor target and responsively produce at least one second sensor signal that is indicative of a location of the second clutch fork along the transmission axis.

19. The power transmitting component of claim 18, wherein the first sensor comprises a plurality of first Hall-effect sensors that are spaced apart along a first sensor axis that is parallel to the second axis and wherein the second sensor comprises a plurality of second Hall-effect sensors that are spaced apart along a second sensor axis that is parallel to the third axis.