Drive assembly with selective disconnect

Patent metadata

Field	Value
Publication number	US-9493230-B2
Application number	US-201314086001-A
Country	US
Kind code	B2
Filing date	Nov 21, 2013
Priority date	Nov 21, 2013
Publication date	Nov 15, 2016
Grant date	Nov 15, 2016

Abstract

A drive assembly with selective disconnect includes a motor with a motor drive shaft; a harmonic drive coupled to one end of the motor drive shaft; an output shaft coupled to the harmonic drive; and a retracting mechanism that selectively retracts the motor drive shaft axially to decouple the motor drive shaft from the harmonic drive.

First claim

The invention claimed is:

1. A drive assembly with selective disconnect comprising:
a motor with a motor drive shaft, the motor drive shaft having a first end and a second end;
a harmonic drive coupled to the first end of the motor drive shaft;
an output shaft coupled to the harmonic drive; and
a retracting mechanism that selectively retracts the motor drive shaft axially to decouple the motor drive shaft from the harmonic drive, the retracting mechanism comprising:
a locking mechanism located at the second end of the motor drive shaft, the locking mechanism having a first end and a second end, the first end of the locking mechanism located radially outside the motor drive shaft;
a solenoid connected to the second end of the locking mechanism, the solenoid being configured to selectively retract the locking mechanism axially to move the locking mechanism from a locked position to an unlocked position; and
a spring attached to the motor drive shaft, the spring being configured to retract the motor drive shaft when the solenoid moves the locking mechanism into an unlocked position.

2. The assembly of claim 1 , wherein the motor drive shaft is connected to a wave generator in the harmonic drive.

3. The assembly of claim 1 , wherein the radially inner surface of the locking mechanism is partially tapered to allow a plurality of ball bearings to move radially outward as the locking mechanism is retracted into the unlocked position and radially inward as the locking mechanism is moved into the locked position.

4. The assembly of claim 3 , wherein the locking mechanism is in the locked position when the plurality of ball bearings are located in a groove radially around the motor drive shaft.

5. The assembly of claim 1 , further comprising:
an actuator connected to the output shaft.

6. The assembly of claim 2 , wherein the wave generator is retracted out of the harmonic drive when the retracting mechanism selectively retracts the motor drive shaft.

7. The assembly of claim 1 , wherein the retracting mechanism selectively retracts the motor drive shaft axially in response to feedback from the output shaft or the electric motor.

8. The assembly of claim 1 , wherein the solenoid selectively moves the locking mechanism axially from the unlocked position to the locked position.

Assignees

• Hamilton Sundstrand Corp

Inventors

• Balsiger Derick

Classifications

• F16H63/34

  Locking or disabling mechanisms · CPC title

• F16H37/04

  Combinations of toothed gearings only (F16H37/06 takes precedence) · CPC title

• B64C13/42

  having duplication or stand-by provisions · CPC title

• Y10T74/19614

  Disconnecting means · CPC title

• F16H49/001 Primary

  Wave gearings, e.g. harmonic drive transmissions · CPC title