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. 27, 1986
Filed:
Nov. 14, 1984
Timothy A Ferris, Simi Valley, CA (US);
Stephen M Fortescue, Northridge, CA (US);
Gaston Palombo, Agoura, CA (US);
Dataproducts Corporation, Woodland Hills, CA (US);
Abstract
A motor control system for a high accuracy incremental motion system such as a paper feed system in a high speed printer. The system utilizes a stepping motor which is driven in one of two modes, depending upon its position. During most of the movement from one position to another, the motor is driven as a DC brushless motor. This is accomplished by commutating the phases of the motor so that they are energized around the peaks of their torque curves. The motor is driven in a closed loop fashion, with velocity commands being generated by a velocity profile generator incorporating a microprocessor. Both position and velocity feedback are utilized. Since the motor is driven as a DC brushless motor, traditional control theory methods (e.g., Root locus, Bode, etc.) can be employed. As the motor nears the final desired position, the system switches so that the motor is energized as a step motor. This energization is applied when the motor is less than one motor step from its final position, and causes the motor to be drawn to a null point and held in position. Velocity feedback is provided to damp the motor so as to further decrease positioning time.