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:
May. 03, 1983
Filed:
Jun. 30, 1982
Charles W McVey, Chardon, OH (US);
Stratford Manufacturing, Inc., Chardon, OH (US);
Abstract
A pair of anti-parallel connected NPN transistors function in push-pull manner to regulate alternately current power applied via the transistors to an induction motor driving a fan providing a generally constant motor load. As the transistors apply more or less current to the motor by varying the amount of line voltage applied thereto, the motor speed varies due to more or less pole slippage. The transistors, while reducing the voltage applied to the motor, generally maintain the sine wave characteristics of the applied voltage to preclude high current spikes and other undesirable transients that could result in conventional motor speed circuits utilizing thyristors that are phase-triggered to vary the half-cycle portions of the applied motor voltage.