GB968234A - Method and apparatus for bending and tempering glass - Google Patents

Abstract

<PICT:0968234/C1/1> <PICT:0968234/C1/2> <PICT:0968234/C1/3> In the bending and tempering by blasts of air of glass sheets on skeleton moulds, the mould during tempering is supported in an inclined position and the amount of air directed against opposite surfaces of the sheet is controlled so as to move at least one edge of the sheet away from the shaping surface to permit passage of air between the edge and the shaping surface. As shown in Figs. 2 and 5, moulds 11 are mounted on racks 12 for passage through a heating chamber for sagging the sheet on to the mould and then through a tempering chamber 56 having inclined passageways 57 with opposed nozzles 58 along each side to direct air from the chamber 56 against the bent sheets 38 on the moulds 11. Each mould 11 is supported at its lower end on a rod 21 fixed by pins 24 to the mould and by offset ends 23 to plates 22 on the side rails 13 of rack 12 and at its upper end by rods 28 each side of the mould 11 fixed to support members 25 of angle iron mounted on plates 22 to give the required inclination to the mould 11. As shown in Fig. 7, each mould 40 is mounted on angle-irons 43 extending at the required inclination from the side rails 44 of the rack 41, so that during bending of the sheet, the mould is horizontal and it is then pivoted downwardly to the dotdash position for tempering. The upper end of mould 40 is pivoted on rods 45 journalled in the angle irons 43, the opposite end of the mould being supported on a rod 46 sliding at each end in a slot 49 in a plate 48 secured to the mould 40 and having off-set ends 47 journalled in the angle-irons 43. The mould 40 is held in the upper position by an extension 51 of the end 47 engaging a hook 52 pivoted on angle-iron 43, the hook 52 being removed automatically as the mould 40 passes from the bending furnace to the tempering chamber. The moulds 11 and 40 are of box-like formation and this is stated to control the amount of air so as to move the sheet away from the mould surface, as shown in Fig. 5, but the blasts of air may be controlled so as to effect cooling of the opposite surfaces at different rates. Specification 968,233 is referred to.