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:
Aug. 10, 2004
Filed:
Aug. 27, 2002
Volker Lurk, Offenburg, DE;
Joerg Sutter, Gaggenau, DE;
Wolfgang Krauth, Achern-Sasbachried, DE;
Wolfgang Schwenk, Oberkirch-Tiergarten, DE;
Claude Berling, Drusenheim, FR;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
An electronically commutatable motor having field windings activatable in sequence with a commutation frequency via semiconductor output stages using control signals connectable and disconnectable from a direct voltage supply, the control signals being clocked using pulse width modulation. Noise generation from connection and disconnection of the current applied to field windings is minimized by flattening of the rising and/or falling edges of the current in the field windings. The pulse width ratio increases in the rising edges of the control signals from a low initial value to an operating value assigned to the setpoint as a function of a selected setpoint for the motor speed or output, and, in the falling edges of the control signals, the pulse width ratio starts from the existing operating value and is reduced to a lower final turn-off value as a function of the existing actual value of the speed or the output of the motor.