METHOD FOR KEEPING PREDETERMINED DISTANCE BETWEEN NOZZLE AND WORKED SURFACE AT LASER WORKING AND APPARATUS FOR PERFORMING THE SAME Russian patent published in 2003 - IPC

FIELD: laser working of different materials, possibly cutting, welding, marking, engraving in different branches of machine engineering. SUBSTANCE: method comprises steps of measuring static pressure in gap between nozzle of focusing unit and worked surface and simultaneously measuring static pressure inside nozzle; keeping predetermined distance between nozzle and worked surface according to change of pressure in gap under nozzle at stable pressure inside nozzle; at simultaneous change of pressure under and inside nozzle keeping said predetermined distance according to pressure change inside nozzle. In order to realize such method apparatus includes pickup designed for detecting static pressure of technological gas inside nozzle and placed in housing of focusing unit between lens and nozzle; circuits for amplifying and compensating signals; system for comparing signals. Each pickup is connected through circuits for amplifying and compensating signals with system for comparing signals electrically connected with drive for moving focusing unit. EFFECT: enlarged range of keeping predetermined distances (increased due to less distances) until worked surface, elimination of nozzle falling onto worked surface. 2 cl, 2 dwg