GB1316741A - Moulding - Google Patents

Abstract

1316741 Injection moulding machines BRITISH UNITED SHOE MACHINERY CO Ltd 23 July 1970 [24 April 1969] 21121/69 Heading B5A A moulding machine comprises injection mechanism 150 mounted for horizontal arcuate movement about a vertical central axis, a plurality of mould stations 50 disposed in an are about the axis, and indexing mechanism arranged to move the injection mechanism arcuately about the axis and radially of the axis into operative association with each mould assembly in turn, the arcuate movement ceasing upon engagement of a sensing device movable with the injection mechanism with a sensing member 58 at a mould station. The invention is applied to the moulding of shoe bottom units of cellular material e.g. polyurethane onto uppers disposed on lasts 98. The injection mechanism 150 is mounted on a trolley 38 having two pairs of forward wheels 39 and two pairs of rearward wheels 40 mounted on rails 34 forming part of a carriage 30. The trolley 38 is movable along the rails 34 by means of a piston and cylinder 43. The carriage 32 is mounted at one end on a shaft 22 and at the other end on wheels 35 running on rails 27 arranged circumferentially of the machine. A chain 108 engaging sprockets 104 is coupled to the carriage 32 and driven by a motor (not shown). When the trolley 38 and injection mechanism are moved radially outwardly to the injection position a positioning member 55 on the trolley moves between two positioning rollers 31 on the carriage 32 and then between two positioning rollers 53 of the mould station. Each mould station also comprises control mechanism including a timer control switch. Fig. 10 shows side mould members 66, 74, and an injection valve member 84 in its cut-off position. The valve member 84 has an axial groove 86 and can be moved to open position by rotation about its axis. Means are also provided for determining the quantity and density of the injected material (Figs 3, 3a, 4, not shown), and for varying the ratio of the constituents of the mixture fed to the mixing chamber 154 (see Fig. 5, not shown). Injection is effected by a piston (155) mounted in the mixing chamber, and through passages 81, 86, 69 (Fig. 10).