| 摘要 |
PURPOSE:To make a titled device light in weight and small in size and to eliminate the need for manual focusing by utilizing the pressure of an assist gas in maintaining automatically the focal position of laser light in a specified position with respect to the work. CONSTITUTION:When the pressure Pc indicated by a pressure gauge 6 between a flow rate control valve 4 and a nozzle 5 in a laser condenser is set at a certain value, the distance l between the tip of a nozzle cylinder 10 and the work is made automatically constant. Therefore if the pressure Pc is controlled by the valve 4, the cylinder 10 slides vertically with respect to an optical waveguide cylinder 10. Since the cylinder 10 is supported on a cylinder 7 by means of a balancing spring 13, the desired distance l can be set by moving upward or downward the cylinder 10 in its axial direction. If the surface of the work is rugged, the cylinder 10 maintains the distance l constant by moving upward or downward by following up to the ruggedness during working and therefore the focal position of a condenser lens 12 is maintained always in the specified position with respect to the top surface of the work. |
