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. 28, 1997
Filed:
Nov. 15, 1995
Ekkehard Bolte, Aachen, DE;
Jurgen Halfmann, Herzogenrath, DE;
U.S. Philips Corporation, New York, NY (US);
Abstract
A control circuit for controlling the speed and stopping time of an electronically commutated motor having a rotary drive member and a stator having at least one phase coil, electric power being supplied to the phase coils by current supply elements which are controlled by the control circuit to obtain a given phase voltage and a given load angle during operation. In response to a supplied stop signal the control circuit decelerates the drive member by controlling the phase voltage and load angle so as to produce a deceleration force which changes dependent on the speed of the drive member; there being a high speed range over which the deceleration force increases to a maximum value as speed is reduced; an intermediate speed range over which the deceleration force remains substantially constant at the maximum value as speed is further reduced, and a low speed range over which the deceleration force reduces as speed is still further reduced to a stop. The intermediate range adjoins the low range at a speed at which the deceleration force which would result from direct short-circuiting of the phase coils would substantially reach a maximum value. A significantly reduced stopping time can be obtained.