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Method and apparatus for electromagnetically braking a motorAn electromagnetic braking system and method is provided for selectively braking a motor using an electromagnetic brake having an electromagnet, a permanent magnet, a rotor assembly, and a brake pad. The brake assembly applies when the electromagnet is de-energized and releases when the electromagnet is energized. When applied the permanent magnet moves the brake pad into frictional engagement with a housing, and when released the electromagnet cancels the flux of the permanent magnet to allow a leaf spring to move the brake pad away from the housing. A controller has a DC/DC converter for converting a main bus voltage to a lower braking voltage based on certain parameters. The converter utilizes pulse-width modulation (PWM) to regulate the braking voltage. A calibrated gap is defined between the brake pad and permanent magnet when the brake assembly is released, and may be dynamically modified via the controller.
Document ID
20110023489
Acquisition Source
Headquarters
Document Type
Other - Patent
Authors
Davis, Donald R.
Radford, Nicolaus A
Permenter, Frank Noble
Parsons, Adam H
Mehling, Joshua S
Date Acquired
August 25, 2013
Publication Date
November 29, 2011
Subject Category
Electronics And Electrical Engineering
Report/Patent Number
Patent Number: US-Patent-8,067,909
Patent Application Number: US-Patent-Appl-SN-12/474,430
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
US-Patent-8,067,909
Patent Application
US-Patent-Appl-SN-12/474,430
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