Methods for regulating the position of a plunge mechanism of a cartridge engaging assembly

摘要

Methods for controlling the position of a plunge mechanism which is mounted to a cartridge engaging assembly are disclosed herein. In one method, the position of a plunge mechanism associated with a cartridge engaging assembly is regulated by 1) providing a reference mark on the plunge mechanism, 2) detecting a size of the reference mark on the plunge mechanism, and then 3) determining the position of the plunge mechanism based on the size of the detected reference mark. In another method, a plunge mechanism is moved to an extended position within a cartridge engaging assembly by 1) initiating movement of the plunge mechanism from a retracted toward an extended position in accordance with an open loop control schedule, and then 2) after moving the plunge mechanism for a predetermined distance, switching control of the movement of the plunge mechanism to a closed loop control schedule, and monitoring a detector which detects a reference mark provided on the plunge mechanism.