Laser robot with approach time from origin to a starting position minimized

A multi-articulated laser robot including a multi-articulated laser robot unit, and an additional motion-axis means provided with two feed motors for feeding the laser beam projecting nozzle of the laser robot unit for a straight approach travel along a straight approach path from a position corresponding to a predetermined position of origin on a workpiece to a position corresponding to a starting position on a desired machining locus, and feeding the laser beam projecting nozzle from the position corresponding to the starting position along the desired machining locus, and control means for controlling the operation of the additional motion-axis means, said control means comprising in combination:

• a storage means capable of storing, as preset machining conditions, a distance R for said straight approach travel, a predetermined quick-feed speed V0, a predetermined machining speed V1, respective time constants corresponding to respective times necessary for a feed speed to increase from zero to said predetermined quick-feed speed, and necessary for a machining speed to increase from zero to said predetermined machining speed;
• a calculating means capable of calculating, on the basis of said machining conditions stored in said storage means,
• a first approach time necessary for machining the workpiece by a laser beam from said position of origin selected as a piercing position where the laser beam projected from said laser beam projecting nozzle pierces the workpiece to said starting position on said desired machining locus at said predetermined machining speed along a straight path, and
• a second approach time necessary for quick-feeding the laser beam projecting nozzle from a position corresponding to said position of origin to a position corresponding to a predetermined piercing position at said predetermined quick-feed speed faster than said predetermined machining speed by selecting said predetermined piercing position at a position near said starting position on said straight approach path, and for carrying out the laser-beam machining after piercing the workpiece from a predetermined point on the straight approach path to said starting position at said machining speed by feeding the laser beam projecting nozzle along a straight path;
• and
• a command control means for providing a quick-feed command to said two drive motors only when said second approach time is determined to be shorter than said first approach time from comparison of said first and second times calculated by said calculating means.