GB814995A - Method and apparatus for bending glass sheets - Google Patents

Abstract

814,995. Bending glass sheets. LIBBEYOWENS-FORD GLASS CO. Aug. 7, 1956 [Aug. 15, 1955], No. 24119/56. Class 56. A method of bending a glass sheet comprises supporting the sheet on a mould having a convex shaping surface while heating the sheet to the softening point and applying a force of progressive and substantially evenly increasing magnitude to an end of the glass sheet to bend said end towards the mould shaping surface. In apparatus to carry out the method, the bending mould 12 is supported on a rigid rack 13, 14, 23 by means of columns 16, 22 the rack having guide rails 15 for passing the rack through a bending furnace with roll-type conveyers. The mould 12 comprises a stationary centre section 17, with convexly curved shaping rails 19 joined by rods 20 and resilient guide bars 21 outside the rails to position a glass sheet, and end sections 18, movable relative to the section 17, with curved side rails 24 connected by a bar 26 and aligned with rails 19 and an end rail 25 projecting beyond the rails 24. Each end section 18 is pivoted between columns 16 by stub shafts 28 through lever arms 27 rigid therewith and with the ends of rail 25, one of the shafts 28 extending beyond the column 16 where it is secured to an actuating arm 30 having a movable weight 34 screwed thereon. Clamps 35 along the rail 25 are used to hold the glass sheet 41 and transmit the force of the falling weight 34 thereto as the glass becomes soft and the end sections 18 move from the dot-dash position of Fig. 2 to the full line position. Each clamp has an arm 39 freely rotatably mounted on the tip of a shaft secured in a tube 38, a spring lying between the bottom of the tube and the arm. To ensure synchronous movement of the end sections 18, the arms 30 are interconnected by links 48, 43 and 48, 44 between the shafts 28 and a bar 42 pivoted at 45 to one of the columns 22. The moulded sheets may then pass through an annealing lehr. Specification 763,698 is referred to.