Learning programmable limit switch and method providing real-time passive feedback

Abstract

This invention relates to a learning programmable limit switch for use in a motion system which provides passive feedback to a controller. The learning programmable limit switch is capable of causing the motion control system to operate in accordance with a user-programmed motion profile. The learning programmable limit switch provides the capability of accurately “learning” and controlling the positions at which a motion system changes velocity, as well as the timing at which the system causes a driven mechanism to, for example, stop. The system is intended for use in variable speed drives, hydraulic, pneumatic drive systems or any system where real time, passive feedback control is desired. In one typical environment, the learning programmable limit switch is connected to an output shaft of a driver. The outputs of the learning programmable limit switch are turned ON/OFF based upon the detected angular position of the output shaft. These outputs are then fed back to a controller, such as a programmable logic controller or PLC, to be used as passive feedback for the PLC to know when to engage/disengage the drive system which is typically a motor, clutch/brake system. The PLC then initiates the drivers motion, with the learning programmable limit switch detecting and tracking such motion, via the output shaft rotation, and cycle its outputs based upon an user-programmed motion profile.