GB335491A - - Google Patents

Abstract

335,491. Budd Wheel Co., (Assignees of Tarbox, J. P., and Reed, G. B.). Jan. 26, 1929, [Conventon date]. Welding wheels. - Hollow members, such as spiders of sheet metal artillery wheels for automobiles &c., are flash welded by applying pressure to the outside of one of the elements and a vielding pressure to the interior thereof while bringing it into welding position with relation to the second element. The halves of a spider 34 are flash welded between a, fixed die 30 and an hydraulically operated die 31 to which the terminals of an annular series of transformers 39 are connected. The lower half is first placed on the die 30 and a series of radial yielding wedgebars are placed over the spoke elements 32 and are simultaneously or subsequently expanded, whereupon the upper half is placed with its elements 33 over the bars and the die 31 is operated to perform the weld, the parts being clamped between the ties and the wedges which yield to the pressure of the die 31 to perform the flash weld. In one form each internal bar may consist of two parts 41. 42, Fig. 14, expanded by a spring 55 compressed by a nut 56 after insertion. The parts 41, 42, Fig. 14, expanded by a spring 55 compressed by a nut 56 after insertion. The parts 41, 42 may, however, be carried respectively by extensions 47<1> from cylinders 46 movable by air pressure on fixed pistons 44 and by links 50 secured to the piston-rods of cylinders 49. The cylinders 46 are moved forwards simultaneously to insert the bars in the spokes by pneumatic pressure from a high pressure line 65 through connected valves. The pistons 49<1> are retracted to expand the wedges by air pressure throush connected valves from a low pressure line 64 and are pushed forward to contract the wedges by high pressure from the line 65. The high and low pressure lines may be connected through a valve 67 when necessary. The wedge bars may be provided with engaging side plates 51, 52, Fig. 10, the upper bar 42 having a wear resisting plate 53 and leaves of insulation 58 being placed between the bar 41 and the element 32. In another form, Fig. 13, the bar 41 may be embraced by a layer of fibre 51 coated on its lower surface with metal by spraying, and the bar 42 may be covered by a U-shaped plate 52. In order to avoid displacement of the insulation 58 during insertion of the wedge bars, the cylinders 46 may be raised by mounting thereon dogs 60 with edges 61, 62 of different radii to engage guides 63, pins 66 being provided to engage detents 64, 65 at the ends of its movement to bring either of the edges into engagement with the guides.