| 摘要 |
PURPOSE:To measure the absolute distance value between the reference point on a machine tool and a tool, by providing an ultrasonic wave emitting means, which emits ultrasonic waves, along a moving path of the tool on the machine tool. CONSTITUTION:A tool 5 is supported by a moving table 2 of a lathe 1. An ultrasonic wave emitting means 6, which emits a ultrasonic wave R along the moving path of the tool 5, is provided. A first ultrasonic wave reflecting means 7 is provided at the tool 5. A second ultrasonic wave reflecting means 8 is provided at the end of the moving path of the tool. An ultrasonic wave receiving means receives the reflected waves S and T from the first and second reflecting means 7 and 8. A first distance measuring means 10 computes the distance of the tool 5 from the reflected waves S and T. The output of an incremental distance measuring means 13 is inputted to an absolute distance measuring means 14 together with the output of the distance measuring means 10. The absolute distance is judged by a judging means 15. Thus the position of the tool can be accurately measured. |
