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:
Jun. 26, 1990
Filed:
Oct. 14, 1988
Joseph C Gundlach, Oak Ridge, TN (US);
Acraloc Corporation, Oak Ridge, TN (US);
Abstract
An electronic braking circuit, for use with normal motor energizing circuits, to achieve rapid and controlled stopping of rotating AC motors after removing the driving power. The braking circuit comprises a transformer having a relatively high voltage-low current AC output, e.g. 120v fused at 15A, which is rectified by a full wave bridge rectifier. A phase-controlled triac is provided for selectively applying the unipolar output of the rectifier to the windings of the motor, causing a unidirectional current flow through the windings which charges the inductance of the windings and generates a braking torque. One or more diodes are provided for discharging the inductance of the motor windings during the non-conducting periods of the triac, thereby continuing the unidirectional current flow through the windings. Phase control circuitry is provided for determining the conducting and non-conducting periods of the triac.