US Patent No. 9,314,859

CONTACT DETECTION APPARATUS FOR WIRE ELECTRICAL DISCHARGE MACHINE WITH CAPABILITY TO VARY APPLIED GAP VOLTAGE


Patent No. 9,314,859
Issue Date April 19, 2016
Title Contact Detection Apparatus For Wire Electrical Discharge Machine With Capability To Vary Applied Gap Voltage
Inventorship Tomoaki Matsunaga, Yamanashi (JP)
Yushi Takayama, Yamanashi (JP)
Akiyoshi Kawahara, Yamanashi (JP)
Assignee FANUC CORPORATION, Yamanashi (JP)

Claim of US Patent No. 9,314,859

1. A contact detection apparatus for a wire electrical discharge machine, said apparatus comprising:
a voltage application unit configured to apply a detection voltage to detect contact between a wire electrode and a workpiece
during non-machining periods;

a contact determination unit configured to determine contact or non-contact between the wire electrode and the workpiece based
on changes in the detection voltage applied by the voltage application unit; and

a controller configured to change, during the non-machining periods, a voltage value of the detection voltage applied by the
voltage application unit according to a property of the workpiece.