GB1236636A - Apparatus for welding and cutting workpieces - Google Patents

Abstract

1236636 Electric heaters MESSER GRIESHEIM GmbH 12 July 1968 [14 July 1967] 33333/68 Headings F4W W55 W45D and W21 [Also in Divisions A5 B3 B5 C1 and G2] Radiation from a source 23 in a chamber 10 emerges through an aperture 25 in the chamber wall and is focused at a working focal point 24 on a workpiece 15, Fig.1 (not shown), and a gas is directed through an outlet port 26 of the chamber 10 towards the workpiece to deflect any vapours emitted by the heated workpiece away from the chamber 10. The gas is supplied at the rear end of the chamber 10 or directly to the outlet port 26 which is fastened on the front end of the chamber in front of the aperture 25. A protective screen 44 of quartz glass seals the chamber 10. The gas may cool the radiation source 23, or may be a protective gas when welding easily oxidizable materials, or may be oxygen when the apparatus is used for autogenous flame cutting. Source 23 is a halogen quartz lamp, or a gas-discharge or arc lamp, or is a tungsten filament in an evacuated chamber 10. Source 23 may be focused at f 2 on one end of a fibre focusing system 63, Fig.8, thereby displacing the working focal point to the front end 64 of the glass fibre rod 63. The rod has a bore 65 for the supply of protective gas. The fibre focusing system may be a bent rod 69, Fig.9, and the protective gas is fed through a separate pipe 72 to an annular passage 73 round the rod 69. The final gas jet may be focused, Fig.10 (not shown). The chamber 10 is pivotally mounted by a swivelling arm 11, Fig.1 (not shown), and is used for welding and cutting. Welding plastics is referred to, including sealing evacuated containers or ampoules and welding inside evacuated containers. Other applications are in the glass processing industry and for the fusion of cells in brain surgery. A converging lens is then placed in front of the fibre focusing system. Chamber 10 has a partly ellipsoidal part 16 and a partly spherical part 17, the source 23 being placed at one focus f 1 of the ellipse and at the centre of the sphere. The radiation is then focused at the other focus f 2 of the ellipse. Parts 16, 17, have a reflecting coating of gold. Optical, infrared and ultra-violet radiation are specified. The support for source 23, Fig.3 (not shown), comprises ceramic rods 30 enclosing the current supply leads and covered with reflecting material. The magnitude and duration of the voltage are controllable, Fig.1, (not shown). Chamber 10 has additional cooling air forced therein by a blower 45, Fig.1 (not shown), exiting via outlet 46.