| 摘要 |
1325572 Injection-moulding BRITISH UNITED SHOE MACHINERY CO Ltd 5 Oct 1970 [6 Oct 1969] 47194/70 Heading B5A Injection moulding apparatus comprises a mould 16, Fig. 9, having a cavity 230 and sprue passage 228 adjacent the outlet passage 222 of the injection mechanism, the mould having a member 234 which closes the sprue passage on completion of injection and wipes material from the surface around the outlet 224. As shown, the apparatus comprises twelve mould stations (11, Fig. 1, not shown) to which the injection mechanism is rotated in turn, the mechanism being advanced to co-operate with a mould 16 by cylinder (48, Fig. 2, not shown). Components to produce a cellular polyurethane are metered in chambers (130, 132, Fig. 3, not shown) each having a ram (134, 136), the quantities being determined by positions of stop switches (S4, S6). Material is passed into chambers (130, 132) through (111, 112) past valves (V3, V4, Fig. 5, not shown), and subsequently forced therefrom into mixing chamber 90 past valves (V1, V2), mixing being effected by paddle (106). After mixing, ram (88) in chamber (90) is advanced by cylinder (84) to inject the material through passages 116, 222 to nozzle head 224 and through sprue passage 228 into mould cavity 230 for forming shoe bottom units on shoe upper assemblies. A purging member 226 is advanced to remove material from passage 222 and a closure member 236 is moved along slideway 235 on mould extension 232 to wipe the surface 237 of head 224 and close sprue passage 228 by its rearwardly tapered end 236. Member 234 is moved by fingers (218, 220, Fig. 6, not shown) of pivot arm (208) by means of cylinder (202). A series of bolts (66, Fig. 2) one for each mould, is mounted on a base (64) which is rotated with the injection mechanism so that the lowermost bolt (66) corresponds to the mould station (11) at which the mechanism is located, the length of bolts (66) being regulated to vary the total quantity of material delivered from metering chambers 130, 132. A bar (150), pivoted at (152), is engaged with the lowermost bolt (66) at each position by means of cylinder (154) thereby moving the supports (164, 170) on which the various stop switches are mounted. |
