The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 16, 1999
Filed:
Aug. 19, 1997
Mark G Hanley, Grayslake, IL (US);
Guy P Caliendo, Algonquin, IL (US);
Dean B Anderson, Wonder Lake, IL (US);
Siemens Building Technologies, Inc., Deerfield, IL (US);
Abstract
An electromechanical actuator maintains an external device to which the actuator is connected at an operating position when power is applied to the actuator, and allows the external device to return to a default position when the power is removed. Included in the actuator is a housing and an output coupling rotatably mounted thereon. The output coupling is configured to be connected to the external device and displaces the external device between the operating position and the default position. A driving device is mounted in the housing for providing a torque to the output coupling to displace the external device between the default position and the operating position when the driving device is energized. Also provided is a torque transmitting device for transmitting and changing the torque from the driving device to the output coupling. The torque transmitting device is cooperatively engaged to and is located between the driving device and the output coupling. Operatively connected to the torque transmitting device, a retracting device is configured for exerting a retracting force to return the external device to the default position via the transmitting device when the power to the actuator is removed. An important feature of the invention is a piezoelectric braking device for exerting a braking force on the driving device for maintaining the output coupling at the operating position against the retracting force exerted by the retracting device when the braking device is activated, and for releasing the braking force when the braking device is deactivated.