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:
Oct. 23, 1990
Filed:
Mar. 03, 1989
Enrico Vasconi, Varano Borghi, IT;
Carlo Mazzucchelli, Fagnano Olona, IT;
Diego Torriani, Cernobbio, IT;
Mario Giganti, Milan, IT;
Whirlpool International B.V., Eindhoven, NL;
Abstract
A motor control circuit measures the motor voltage to determine actual motor speed. This speed voltage is the sum of the back emf and armature loses. The control circuit receives a reference voltage proportional to the desired motor speed and a further signal voltage indicative of the motor armature losses. These three voltages are combined to provide a first error signal representing the difference between the reference voltage and the motor back emf. This error signal is substractively combined with a signal representative of the motor power to produce a control signal for a modulator circuit which in turn controls a semiconductor switch in series with the motor.