Length measuring machine contact sensing probe - has sensing circuit monitoring probe vibrations generated by transducer in contact element

摘要

The contact sensing probe for a length measuring machine comprises a contact element (11, 21) which includes a transducer (13, 17). The transducer converts a varying electric current into vibrations of the contact element or vice versa. A sensing circuit detects engagement of the contact element with an object by sensing the consequent change in electric current passing through the transducer. The vibrations are damped when the element contacts an object and this may be sensed by the consequent change in the applied current or in a generated current if the element is mechanically vibrated.