Patent CH-700111-B1 (CH)
Title: Machine for making three-dimensional workpiece using focused beam of laser light causing local evaporation of particle of matter on workpiece surface, comprises laser machining head, laser source, galvanometer scanner, and optical fiber
Inventor: PAGANELLI DINO
IPC: B23K26/08
Filed: 2009-09-25
Abstract: The machine for making any three-dimensional workpiece using a focused beam (26) of laser light that causes local evaporation of a particle of matter on the surface of the workpiece, comprises a laser machining head (8), a laser source for producing a beam of laser light, a galvanometer scanner (25) for reflecting the beam of laser light in the output of the laser machining head, and an optical fiber (24) placed along a system of cables. The machine has three orthogonal linear axes (X, Y, Z) and two rotary axes (A, B) perpendicular to each other. The machine for making any three-dimensional workpiece using a focused beam (26) of laser light that causes local evaporation of a particle of matter on the surface of the workpiece, comprises a laser machining head (8), a laser source for producing a beam of laser light, a galvanometer scanner (25) for reflecting the beam of laser light in the output of the laser machining head, and an optical fiber (24) placed along a system of cables. The machine has three orthogonal linear axes (X, Y, Z) and two rotary axes (A, B) perpendicular to each other to turn a laser machining head around a horizontal axis (B) and rotating the workpiece about a vertical axis (C). The galvanometer scanner consists of two mirrors pivoting around two perpendicular axes. The laser source transmits its energy to the laser machining head through the optical fiber. The optical fiber leads to an optical output head (27), which defines the optical axis of the beam of laser light to vaporize the material. The laser machining head comprises a frame and a housing, and is repositioned and rotated periodically to obtain a new area of the workpiece. The optical output head is rigidly attached to the frame or housing of the laser machining head so that output head remains secured in the optical output during rotation of the laser head around the horizontal axis. A mechanical sensor and/or a charge-coupled device camera are rotated with the laser machining head during its rotation around the horizontal axis. The laser machining head is equipped with a mechanical device designed to protect members in case of accidental collision. The mechanical device comprises screws working under an effect of excessive shear thus allowing the laser machining head to escape from constraint, and security flange bolts. The machine is equipped with a mechanical relief for traction and torsion for releasing the laser machining head from structural stress caused by the profusion of electrical connections, pipes and waveguides channeled through the raceway leading to a series of channels. The mechanical relief device is carried by a margin, which rotates the channels. A plate supporting the laser machining head is subjected to a motor shaft along the axis of rotation. An adjustable suction nozzle is used to collect the polluted gas, and rotates around an axis perpendicular to the axis of rotation of the laser machining head. The suction nozzle is equipped with a micro-switch that stops the machine in case of collision. A blow nozzle is used for injecting a gas flow in the machining area, and rotates around an axis perpendicular to the axis of rotation of the laser machining head. The blow nozzle is primarily directed to the machining area, and secondarily to the opposite area of the suction nozzle so that the flow of clean gas polluted by dust from the machining area is collected by the suction nozzle. The mechanical sensor is mounted on a retractable carriage, and extends through the action of a cylinder when a measurement is performed.