US Patent No. 10,092,978

LASER PROCESSING APPARATUS CAPABLE OF RETRACTING PROCESSING NOZZLE UPON POWER FAILURE


Patent No. 10,092,978
Issue Date October 09, 2018
Title Laser Processing Apparatus Capable Of Retracting Processing Nozzle Upon Power Failure
Inventorship Hiroaki Tokito, Yamanashi (JP)
Assignee FANUC CORPORATION, Yamanashi (JP)

Claim of US Patent No. 10,092,978

1. A laser processing apparatus comprising:a processing nozzle configured to irradiate a workpiece with laser beam;
a driving mechanism configured to move said processing nozzle and said workpiece relative to each other;
a gap sensor configured to detect a gap between said processing nozzle and said workpiece;
a gap control section configured to refer to a measured value detected by said gap sensor and calculate a manipulating variable used for controlling said driving mechanism so as to maintain said gap during execution of laser processing at a first dimension;
a power monitoring section configured to monitor electric power supplied from a power supply and send an abnormality detection signal to said gap control section when an abnormality occurs in the electric power; and
a control action switching section configured to switch a control action of said gap control section so as to increase said gap from said first dimension when said abnormality detection signal is sent to said gap control section during execution of laser processing,
wherein said control action switching section includes a target value selecting section configured to select, as a target value of said gap, either one of said first dimension that is previously determined and a second dimension that is previously determined to be larger than said first dimension, and wherein,
when said abnormality detection signal is sent to said gap control section during execution of laser processing, said target value selecting section selects said second dimension instead of said first dimension, and said gap control section calculates a manipulating variable used for controlling said driving mechanism so as to maintain said gap at said second dimension.