Digital retorque measuring apparatus

摘要

A microcomputer based system is designed to accurately detect the amount of previously applied torque to a fastener by way of a retorque test in which torque is subsequently applied to the fastener in the tightening direction until breakaway occurs. As torque is subsequently applied to the fastener a microprocessor operates to sample an analog torque input signal and convert it into discrete digital samples. These digital samples are stored in sequential memory locations during the tightening process. The microprocessor stops generating any further samples once a window containing the values of interest has been defined in memory. Then, the microprocessor examines the stored window samples in more detail to detect the sample value associated with the amount of torque previously applied to the fastener.