Patent GB-810380-A (GB)
Title: Apparatus for forming curved glass panes
IPC: C03B23/027
Filed: 1957-02-07
Abstract: 810,380. Shaping glass sheets. SHATTERPROOF GLASS CORPORATION. Feb. 7, 1957 [March 1, 1956], No. 4267/57. Class 56. Apparatus for forming curved glass panes comprises an articulated mould having end and centre pane supporting sections B, C with concave top faces 9, 11 that are movable upwardly and downwardly from a pane receiving, portion in which the top faces have pane engaging portions 29, 30 in horizontal alignment to a moulding position in which the concave top faces 9, 11 are disposed end to end and conform to the convex face of the curved pane and means connecting the end and centre sections in counterbalancing relation whereby the end and centre sections are maintained in engagement with a glass pane during the sagging of the pane into the mould and the movement of the sections to the moulding position. As shown in Figs. 1, 3 and 6 the end sections B are each supported on posts 3, on a frame 1 having runners 2, by links 4 pivoted at 5 to the posts 3 and having a transverse shaft 6 journalled in straps 7, the end section B having brackets 8 attached to the shaft 6. The links 4 are substantially vertical in the closed position of the mould. The centre section C is connected to the end section B by hinge connections 16 each including a U-shaped hinge member secured in a recess 17 in an end of the strip 9 of the end section, with its bottom 18 engaging the end face of the strip at the bottom of the recess 17 and with the inner face of the bottom 18 flush with the main face 19 of the strip 9. A plate 20, slightly thicker than the strip 11, is welded in a recess 21 in the end of strip 11 and received between the arms of hinge member 16, the end face 22 engaging the inner face of bottom 18 to limit pivotal movement. The end face 23 of strip 11, flush with end face 22, engages end face 19 in the end-to-end position of the mould. The pivot pin 24, which extends through hinge member 16 and plate 20, is offset inwardly of the end faces 22, 23, the plate 20 being cut away at 25 to allow pivoting. The opened mould support the glass cut to final form on the apices 29 of the end sections B and on the ends 30 of the centre strips 11. As the glass softens, the weight on the centre section increases and moves the section downwardly, the end sections moving up to the moulding position. Heat intercepting plates 31 and 32 are provided to maintain a lower pane at a somewhat lower temperature when two panes are moulded together. When glass shaping surfaces with parts of greater curvature are used, Fig. 18-21 (not shown), special means to retard the heating of the end portions are used in place of the heat absorbing plates 32 and comprise relatively thick metal plates, to absorb the heat, and fit the outer end of the sections only, the plate having an angular inner edge to provide a wider gap for heat to pass to the parts to be bent to a greater curvature. The thickness of the plates may also be varied. To hold the ends of a steeply bent pane against the mould, automatic hold down devices D are provided at each end. As shown in Fig. 3, posts 34 extend at right angles to the end portion of strip 9 and have a connecting portion 35 as guide for a sliding rod 36 with a down turned inner end 37 overlying the glass adjacent the apex 29, the glass being engaged by a tubular metal block 38 or by a solid block loosely supported on the rod. A lever 41 is pivoted at 43 to a post 42 parallel with rod 36 and has a forked end 44 straddling the rod 36 between spaced collars 45, 46. The lower end of lever 41 is bent outwardly at 47 and has a counterweight 48 adjustably secured thereon. In the opened position of the mould the fork 44 engages the collar 45 to maintain the block 38 clear of the glass and as the mould moves to the closed position shown, the weight 48 presses the fork 44 against the collar 46 to hold the glass against the mould. A modified supporting structure for the mould may be used lying within the mould structure so that a number of moulds may be supported on the same frame. The support, shown in Fig. 16, comprises short posts 58 on side bars 53 each having a member 59 attached at its lower end to a horizontal shaft 60 journalled in brackets 61 on the inner side of the post 58. The upper end of member 59 receives a horizontal shaft 62 attached at its ends to brackets 63 rigid with the strip 9 and movement of member 59 is limited by a strap 64 on post 58 having a stop flange 65 and by the post 58 itself in the closed position of the mould. Specification 810,379 is referred to. Reference has been directed by the Comptroller to Specifications 678,708, 727,200, 768,982 and 770,131.