GB1446310A - Electric resistance orthodontic welding apparatus - Google Patents

Abstract

1446310 Welding by pressure SHEFFIELD UNIVERSITY OF C J MINORS and G F BAXTER 9 Aug 1973 [26 Sept 1972] 44321/72 Heading B3R Electric resistance orthodontic welding apparatus comprises a rotatable electrode turret 10 including a plurality of electrodes and releasable locking means including a spring loaded pin engaging a hole in the turret for locking the turret in a plurality of predetermined positions in any of which an electrode is in a welding position. The pin is displaceable against the spring by a manually operable member of the locking means. In an embodiment the apparatus upper head, which is movable up and down, comprises a metal bush 12 mounted for rotation on a sleeve 14 fixed to a mounting bracket 16, the bush carrying four radially arranged electrodes 20, 24 &c. A rod 28 carrying a knob 30 at one end is slidable in the sleeve 14 and carries at the other end a pad 32 on which are secured two locking pins 34, 36 slidably located in bores in the bracket 16 and having tapered ends 34A, 36A normally located in two of four holes 12A provided in the bush 12 under the pressure of a spring 38. To employ an electrode other than the electrode 24 the knob 30 is depressed to free the pins from the holes 12A, the bush 12 is rotated to bring the required electrode into the welding position and then the knob is released to lock the bush in its new position. Both heads of the apparatus may comprise a rotatable assembly or the upper head may be a fixed electrode while the lower head includes the turrent. Both heads may in fact include turrets as described.