STEPPER MOTOR DOOR CONTROL APPARATUS AND METHOD

摘要

18 A door movement control apparatus and method are provided for opening and closing door apparatus with a stepper motor supplied control pulses in response to a command signal indicating the desired movement direction. A table of time delays for the respective control pulses and resulting motor steps provides a desired speed pattern for the door movement. A comparison of the number of motor steps taken with the number of control pulses provided is made to determine when a closing door is obstructed.