METHOD FOR CHECKING TORQUE VALUE OF TORQUE WRENCH

摘要

PURPOSE: To accurately display a set torque value by comparing the voltage corresponding to the set torque value with the voltage appearing accompanying the falling and rising of torque and calculating the max. peak value among candidate values. ;CONSTITUTION: A strain gauge 11 converts torque into voltage and this voltage is amplified to voltage VA by an amplifier 13. This voltage signal VA is compared with the peak value VB stored in a peak holding circuit 15 by a comparator 111 to detect the width of a trough. The signal from a timing circuit 114 having prescribed timing Δt₀ and the signal from a phase reversal circuit 112 are synthesized on the basis of the detection signal by a synthesizing circuit 115 to be stored in a memory 117. In the same way, signals VA, VB are compared by a comparator 119 and, when a trough is prescribed falling quantity ΔT₀, this quantity is stored in a memory 120. The signals stored in the memories 117, 120 operate gate circuit 16 through an AND circuit 118 and the signal VB of the circuit 15 is converted into a signal VC by a peak holding circuit 17 and the ridge value VP of torque is displayed on a display device 18. By this constitution, the max. peak value wherein the time required before dropped voltage rises to reach set torque voltage is a prescribed value or less and dropped voltage is the prescribed value or more among set torque candidates is set to a set torque value.;COPYRIGHT: (C)1995,JPO