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. 31, 2000
Filed:
Jul. 23, 1999
Applicant:
Inventor:
Michael D Cummins, Titusville, FL (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02P / ;
U.S. Cl.
CPC ...
318815 ; 318254 ; 318138 ; 318439 ; 318807 ; 318599 ; 318801 ;
Abstract
A speed control apparatus for varying the speed of an AC motor while maintaining the torque and power constant over a range of angular speeds The AC motor is driven by a D.C. source. A universal conmutator capable of providing two symmetrical non-contending signals with a frequency that can be selectively varied. A microprocessor unit for monitoring the frequency of the signals and control proportionally varying the duty cycle of the signals calculates the necessary duty cycle to maintain the torque constant over a range of angular speeds.