The attachment serves for the programmed laser-beam machining of parts made of various materials in numerically controlled (CNC) milling machines. This includes shape-cutting along an external or internal contour, marking, engraving, welding, and hardening by heat treatment. The attachment is particularly effective in machining parts made of hardened or stainless steel, and in replacing die forging in small-lot production.

The laser-beam machining attachment comprises: a solid-state yttrium-aluminum garnet laser with neodymium (Nd:YAG); a beam-transporting and -forming system; workpiece-fixture devices; a process-gas feed system; the necessary communications, and a manual control unit. The attachment is technologically controlled from the CNC panel of a standard-unit-type milling machine.

The equipment may be adapted to most CNC vertical-milling machines; it is mounted on the machine without subjecting it to any substantial alterations and can, if necessary, easily be removed from it, whereupon the machine may be used in its original mode. With an 0.1 -0.5 kW solid-state Nd:YAG laser, the attachment is compact, reliable, and easy to operate.

The use of an 0.25 kW laser, after special-purpose modernization, makes possible the continuous or pulsed-periodic cutting of steel up to 3-3.5 mm thick; brass and aluminum alloys, up to 1.5-2 mm thick, and rubber, 5 mm thick. The cutting rate is 0.5-1.0 m/min. It can be increased by using machines with a high feed rate of the milling machine table. The dimensions of the machined parts are governed by the characteristics of the standard-unit-type machine.

The attachment has been used with a vertical-milling machine with equipment including a modernized LTN-103 laser (0.25 kW power). It has been employed for shape-cutting (without subsequent treatment) circular saws 200 mm in diameter for woodworking from 2.2-mm-thick steel sheet; for slotting (0.3-mm-wide slots) cylindrical filters for the high purification of drinking water, and for making various machine parts from steel, brass, and aluminum alloys (see figure), and also from rubber, rubberized asbestos, cardboard, and veneer of valuable tree species.

The biggest effect is achieved in using the attachment to machine small parts with dimensions less than 200-300 mm. In this case the attachment, mounted on a CNC milling machine, can successfully compete with laser tools and installations manufactured by leading firms (Rofin-Sinar, Trumpf, and others). The purchase and operation of a laser attachment and a milling machine will cost only a half or even a third as much as that of a laser tool or installation with the same performance characteristics. If a plant already has the necessary CNC milling machine, the purchase of the laser attachment will slash the cost of introducing advanced laser technologies by hundreds of thousands of dollars.

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