| 摘要 |
PURPOSE:To improve measurement precision by selecting the output of a dummy bridge which gives a reference value during the switching of bridge outputs of bridges having an incorporated strain gauge, in measuring strain at plural positions from the bridge outputs. CONSTITUTION:The outputs of bridges 1a-1n having an incorporated strain gauge are inputted to a strain meter 4 while being switched selectively by turning on and off changeover switches 2a-2n by control signals 3a-3n from a control part 5', thereby recording strain at plural points on a recorder 6. In this case, a dummy bridge D stuck to a dymmy plate is set up and given the reference point (zero point) of a measurement system. During the selective switching period of those bridges, the dummy bridge D is selected to prevent a detection signal from fluctuating between the positive and negative greatly, and when the dummy bridge is selected, the reference value is indicated clearly. |
