| 摘要 |
PURPOSE:To introduce precracking simply without requiring so much time and labor, by including an actuator, a load detector (load cell) and a control section for controlling the actuator. CONSTITUTION:A DT test piece 6 is set on a base 10 through a roller 9 and a working rod 4 is lowered to bringing a pressurizing element 5 into contact with the end of the DT test piece 6 on the notch-formed side. An actuator 1 is driven with a driver 8 to detect the load acting upon the DT test piece 6 with a load cell 2. The load detected with the load cell 2 is inputted into a control section 3 to determine whether it is larger than the load value inputted previously by comparison. As the load value shifts to a decrease from the increase, a stop instruction signal is outputted to the driver 8 from the control section 3 to halt the actuator 1 immediately. |
