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:
Jan. 09, 1979
Filed:
Jan. 16, 1978
Wolfgang Kosak, Moglingen, DE;
Peter Werner, Stuttgart, DE;
Hans Gerber, Luterbach, CH;
Ivan Hidveghy, Zuchwil, CH;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A first thyristor, under control of a speed setting provided in an RC circuit varies the phase duration of current supply to the motor during positive halfwaves of the a c supply, and a second thyristor controlled in accordance with the motor current provided through the first thyristor determines the phase angle during which current flows through the motor in the negative halfwave of the voltage supply, so as to maintain the speed at the set value under varying conditions of load. During positive halfwaves, a capacitor is charged to a voltage corresponding to the amount of current flow through the motor and during the following negative halfwave, the charge is increased at a rate set by an RC circuit, resulting in turning on the second thyristor early under heavy load conditions, and late under light load conditions, and indeed not at all under idling conditions.