Electro-mechanical actuator

• US 6,889,578 B2
• Filed: 01/18/2001
• Issued: 05/10/2005
• Est. Priority Date: 01/19/2000
• Status: Expired due to Fees

• Current Assignee: Stoneridge Control Devices, Inc. (Stoneridge Incorporated)
• Original Assignee: Stoneridge Control Devices, Inc. (Stoneridge Incorporated)
• Inventors: Murray, John, Beishline, Eric, Holloway, John, Spaziani, Phillip, Farmer, Bill, Bishai, Macram, Laskin, Irving
• Primary Examiner(s): Graham, Matthew C.
• Application Number:
  US09/765,899
• Publication Number:
  US 20010027146A1
• Time in Patent Office: 1,573 Days
• Field of Search: 746/61, 744/25, 318/15
• US Class Current: 74/661
• CPC Class Codes: E05F 11/405 for vehicle windows
• CPC Class Codes: E05F 11/423 for vehicle windows
• CPC Class Codes: E05F 11/505 for vehicle windows
• CPC Class Codes: E05F 15/697 Motor units therefor, e.g. geared motors
• CPC Class Codes: E05Y 2201/72 Planetary gearing
• CPC Class Codes: E05Y 2800/242 arranged in parallel relationship
• CPC Class Codes: E05Y 2900/55 Windows
• CPC Class Codes: F16H 2035/005 Gearings or mechanisms preventing back-driving braking or locking of screw actuators F16H25/2454
• CPC Class Codes: F16H 37/065 with a plurality of driving or driven shafts F16H37/08 takes precedence
• CPC Class Codes: H02K 16/00 Machines with more than one rotor or stator machines for transmitting mechanical power from a driving shaft to a driven shaft and comprising structurally interrelated motor and generator parts H02K51/00; permanent magnet machines with multiple rotors or stators relatively rotated for vectorially combining the excitation fields or the armature voltages H02K21/029
• CPC Class Codes: H02K 7/10 Structural association with clutches, brakes, gears, pulleys or mechanical starters
• CPC Class Codes: H02K 7/1163 where at least two gears have non-parallel axes without having orbital motion
• CPC Class Codes: H02K 7/1166 comprising worm and worm-wheel structural association with bearings specially adapted for worm gear drives H02K7/081
• CPC Class Codes: Y10T 74/18792 including worm
• CPC Class Codes: Y10T 74/18808 with rack
• CPC Class Codes: Y10T 74/19014 Plural prime movers selectively coupled to common output
• CPC Class Codes: Y10T 74/19828 Worm

Abstract

An electro-mechanical actuator including a plurality of motors for driving an output shaft. The actuator may be incorporated into a window lift mechanism, such as a mechanism including a dual rack and pinion assembly. According to another aspect of the invention there is provided a variety of anti-back-drive mechanisms, e.g. clutches. A clutch according to one embodiment includes locking pawls that resist back-drive. In another embodiment, locking cams rotate relative to a carrier to resist back-drive. An actuator consistent with the invention may incorporate an impact mechanism including a flexible carrier. The carrier flexes to prevent impact forces at an output gear train from coupling to an input gear train.

Claims

1. An actuator for a window lift mechanism, said actuator comprising:

an output shaft for driving said mechanism;

an output gear coupled to said output shaft;

a plurality of motors coupled to said output gear for simultaneously driving said output gear and said output shaft, wherein said plurality of motors comprises a first motor having a first torque ripple characteristic and a second motor having a second torque ripple characteristic, wherein said first torque ripple characteristic is at least partially out of phase with said second torque ripple characteristic to reduce vibration imparted to said actuator by said plurality of motors.

2. An actuator according, to claim 1, wherein each of said motors is coupled to said output gear by an associated gear train.

3. An actuator according to claim 2, wherein a first one of said gear trains comprises a worm gear in meshing engagement with said output gear, said worm gear resisting back-drive of said output shaft.

4. An actuator according to claim 1, wherein said output gear comprises a sun gear of a planetary gear system, and wherein said motors are coupled to said sun gear through a ring gear and planet gears of said planetary gear system.

5. An actuator according to claim 4, wherein each of said motors is coupled to said gear by an associated gear train.

6. An actuator according to claim 5, wherein a first one of said gear trains comprises a worm gear in meshing engagement with said sun gear, said worm gear resisting back-drive of said output shaft.