| 摘要 |
PURPOSE:To enable working abnormality to be easily detected in machining such as cutting by mounting a weight detecting portion on a chuck of a working machine to detect the working defects from the weight of a workpiece. CONSTITUTION:A workpiece W is supported by a chuck 3 on a table 2 and a tool 7 is advanced and retreated by a guide 5 to work the workpiece W. The table 2 is formed with a hole 10 in which a weight detector 9 such as piezo- electric element is received and the workpiece W is placed on the weight detector 9. The piezo-electric element of the weight detector 9 is connected to a substracter and a reference value setter, and the subtracter calculates the differnce between the output value of the weight detector 9 and reference weight value of the reference value setter. A comparator compares the absolute value of the difference with the set value to send abnormality signal to a control of a working machine to stop it when the value of said difference is larger or smaller than the set value. |
