Probe system for coordinate measuring machines

摘要

A probe driving mechanism for displacement measuring apparatuses, capable of carrying out a stable, constant speed probe feeding operation without additionally providing a motor rotation detecting rotary encoder and a tachometer generator. When an output from a scale 20 varies in accordance with the power applied to a motor 18, the power applied to the motor 18 is controlled in accordance with an output from the scale 20. When the variation of an output from the scale 20 becomes small even though the same level of power continues to be applied to the motor 18, a judement that a probe 12 contacts the workpiece. 8 is given, and the power applied to the motor 18 is set smaller. When an output from the workpiece sensor 26 varies, the power applied to the motor 18 is controlled in accordance with one of an output from the scale and that from the workpiece sensor the speed variation of which is larger than that of the other.