Ronald M Teer

US Patent:

47422840, May 3, 1988

Filed:

Dec 9, 1986

Appl. No.:

6/940137

Inventors:

Donald J. Dziubakowski - Seven Hills OH
Erik P. Kristoffersen - Cleveland Heights OH
Ronald J. Teer - Painesville OH

Assignee:

The Babcock & Wilcox Company - New Orleans LA

International Classification:

G05B 501

US Classification:

318624

Abstract:

A controller for close positioning or modulating control of an electric motor is disclosed. The controller compares a signal representative of the demand on the system with a signal representative of the actual position of the motor or a valve associated therewith, and if the difference between the signals exceeds a "deadband" and no action has been taken within a first time interval, and if the last movement of the valve was in the same direction and a second time interval has elapsed, a motor run pulse is generated. If the last movement of the valve was in a direction opposite to that desired, the motor run pulse is extended to overcome "backlash" resulting from the reversal of motor rotation.