| 摘要 |
PURPOSE:To prevent a stylus from descending below the clamp level, by providing a means for controlling a gate circuit which controls drive in Z axis direction based upon the detected result of the present position in Z axis direction of a mobile part, and a clamp level given from an input means. CONSTITUTION:When a microprocessor 15 is determined to be not clamped, and a displacement signal epsilonz in Z axis direction applied from a tracer head 8 satisfies the relation epsilonz<0, such a formula as, Pz (count value of reversible counter 14 showing present position of stylus 9) < Pz0 (cordinates showin clamp level stored in memory 18) is satisfied. Namely, if the present position of stylus 9, drops the clamp level, a control signal is applied to an output unit 16, only signal (a) among output signal a-c is set to ''0'', gate circuit 5Z goes off, for stopping movement in Z axis direction, and clamp profiling is performed. On the other hand, if epsilonz>=0 is satisifed during clamp profiling process, a control signal is applied to the output unit 16 to render signal (a) ''1'', thus a gate circuit 5Z is turned on and clamp profiling is released. Accordingly, there shall be no more possibility of breakage of cutter 12. |
