SHUTTER MECHANISM INCLUDING STEPPING MOTOR CONTROL DEVICE FOR CONTROLLING UPPER AND LOWER LIMIT STOP POSITION CONTROL

摘要

PURPOSE: A shutter mechanism is provided to achieve improved accuracy of position where an object is stopped, without increasing parts count or costs. CONSTITUTION: A shutter mechanism comprises a drum(2) on which an object(3) is wound; a stepping motor(5) electrically connected to the drum in such a manner that the stepping motor rotates the drum so as to selectively wind or unwind the object; a driver electrically connected to the stepping motor such that the driver supplies driving current to the stepping motor; a controller for controlling the driver such that the driver supplies driving current to the stepping motor, wherein the controller includes a memory for storing motor control data; and a load amount detection circuit for detecting the amount of load in the stepping motor through an electrical communication with the stepping motor, and outputting a load signal representing the amount of load to the controller. The controller starts and stops output of command pulse to the driver on the basis of the motor control data stored in the memory and load signal.