Road vehicle loading meter - uses strain gauges connected in two bridges on test plate to measure axle or wheel loads

摘要

The measurement is done by electric evaluation of a resistance change of two strain gauges attached on or in a test plate in the path of the vehicle. The grid of one strain gauge lies in the travel direction, and that of the other is at a right angle to it. They are inserted in bridges. The two strain gauges (X1, X2; Y1, Y2) are so connected that their signals are added. The test signals differ by a certain factor, owing to suitable choice of applied voltage of their resistances (Rx1; Rx2, Ry2) or the like. The distance (A) between one pair of strain gauges (X1, Y1) and the other pair (X2, Y2) is just long enough so as to be equal to the max. possible length (L) of the raised surface (F) of the wheel (W).