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:
Sep. 21, 2010
Filed:
Sep. 18, 2007
Otto Knittel, Soest, DE;
Michael Kriener, Salzkotten, DE;
Otto Knittel, Soest, DE;
Michael Kriener, Salzkotten, DE;
Behr-Hella Thermocontrol GmbH, Stuttgart, DE;
Abstract
In a method for the detection of the rotational position of the rotor of a DC motor with commutator by evaluating the time development of a rotor current signal of the DC motor, said signal comprising a periodic waviness around an average value and comprising current ripples generated by commutation which are superimposed to said waviness, the rotor current signal of a current ripple detector unit () is supplied for detecting the current ripples of the rotor current signal. The rotor current signal is further supplied to a waviness detector unit () for detecting a half or full wave of the rotor current signal. The current ripple detector unit () is arranged to output a current ripple pulse for each detected current ripple. The waviness detector unit () is arranged to output a waviness pulse for each period of the waviness. The output signals of both detector units () are supplied to a logic OR unit () for generating a logic signal. Within a period of the rotor current signal, at least one of the detector units () will output a pulse. Thereby, the logic signal comprises a logic pulse for each period of the rotor current signal.