| 摘要 |
PURPOSE:To make accurate controlling in a short time possible so as to minimize the unbalance value of a bridge by changing the direction of a variable element which is held by being inputted with the unbalance value mechanically in a manner as to assume a fixed direction. CONSTITUTION:The unbalance values of variable elements Rs, Xs are held in an unbalance value input circuit 8a, and the unbalance value after the time having been set in a time setting circuit 13 is held in the circuit 8a. At this time, the previous holding data are transferred into the next comparing data holding circuit 8b. These two data are given to a comparator 9 according to the set conditions of a comparing direction setting circuit 10. Pulses enter the ternary counter of a sequence control circuit 12, by which the variable element is selected and the unbalance value successibly moves its variable direction. Both of Rs, Xs are changed of direction simultaneously whereby the unbalance value is made successively smaller. Here, the variable width of the variable element is changed successively in a time setting circuit 13. When the accuracy of the balance point reaches less than permissible value, the automatic operation is stopped. |
