Programmable controller linear transducer input modules

Abstract

The linear transducer input module is one of several modules mounted in a rack to form a programmable controller. The module's function is to provide position data from an externally located ultrasonic magnetostrictive linear transducer which is connected to some moving part of a machine to the programmable controller's processor module. The ultrasonic magnetostrictive linear transducer digital decoding circuitry (receiving circuitry) is located in the input module on the programmable controller input/output rack. A synchronizing circuit is provided in the module to synchronize the programmable controller's input fetch signals which input module circuitry. A user operable digital offset device is provided in the module for enabling an offset to be added to the ultrasonic magnetostrictive linear transducer position data by a user-selectable amount while accommodating different transducer lengths. User operable calibration circuitry is provided in the module for calibrating the module to ultrasonic magnetostrictive linear transducers with different characteristics. The linear transducer input module provides a numerical display of the digitally offset ultrasonic magnetostrictive linear transducer position data. The linear transducer input module also provides BCD coded output data which is easily connected to such devices as remote digital displays.