| 摘要 |
A material testing machine includes a control system for feedback-controlling, during material testing, the operation of a servo system including an actuator for applying a load to a test piece. During the mounting the test piece to the testing machine, a target displacement of a movable part of the actuator is corrected in accordance with the actual load applied to the test piece so as to prevent the actual load from being excessive. While the amplification factor of an amplifier for detecting the controlled variable is being changed over during the material testing, a control output value supplied from a digital controller of the control system to the serve system is maintained at a value obtained just before the changeover of the amplification factor, whereby the detection scale factor in detecting the controlled variable can be maintained at constant. <IMAGE> |
