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:
Feb. 22, 1994
Filed:
Aug. 05, 1991
Gerold E Schmid, Brookfield, WI (US);
Harnischfeger Corporation, Brookfield, WI (US);
Abstract
A control for a d.c. motor having a d.c. thyristor power supply connected to a d.c. motor and a control circuit for selectively varying and controlling the level of the current provided by the thyristor power supply to the motor. The thyristor power supply provides a plurality of selected output current levels to the motor and the motor has a corresponding plurality of torque levels. The level of the output current supplied by the power supply to the motor is independent of the resistance in the motor circuit. The motor is rotatable in opposite directions and the thyristor power supply will provide output voltage at opposite pluralities corresponding to the rotational direction of the motor.