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. 26, 2002
Filed:
Dec. 22, 1999
Klaus Kronenberg, Sulzbach, DE;
Mannesmann VDO AG, Frankfurt, DE;
Abstract
A method for monitoring the speed of a synchronous motor, the synchronous motor having a permanent magnet rotor ( ) and coils ( ), sinusoidal currents being applied to the coils ( ). Also a device for monitoring the speed of such a motor, wherein in at least one of the coils ( ) the power supply is disconnected and one or more voltage characteristics (U U ) are evaluated which are induced by the permanent magnet rotor ( ) in one or more of the coils ( ) disconnected from the power supply, the minimum duration of the interruption of the power supply of the coils ( ) and the evaluation of the voltage characteristic (U U ) being equal to the temporal spacing between two consecutive zero crossings of the respectively induced voltage characteristics (U U ).