GB831092A - Improved machine for moulding and vulcanizing articles of footwear - Google Patents

Abstract

831,092. Moulding footwear. BRITISH BATA SHOE CO. Ltd. Oct. 23, 1956, No. 32245/56. Class 87(2). Shoe soles are moulded on to uppers by placing the uppers on lasts 19a, Fig. 3, removing moulded soles on lasts 19 along tracks 74 and then moving the lasts 19a along tracks 73 into the moulding position. In operation low pressure fluid is supplied to a cylinder (see Fig. la, not shown) causing a beam 21 to be lowered. As the beam moves downwardly, links 50 are moved inwardly causing (a) members 17 to move the lasts 19 against a central side mould member 2, and (b) side mould members 11, 11a to be moved against the lasts 19. When a shoulder 64 engages a flange 40, further inward movement of the lasts and side mould members is stopped. High pressure fluid is then supplied to the cylinder to cause the top mould members 55 to be moved down against springs 47 to close the mould cavities. The rubber is then vulcanized by electric heating elements or a high frequency system. A thermostatic control 78 may be provided. Thermal insulation e.g. as shown at 66a, may be provided between all the mould members and their supports. After a predetermined time, the machine is opened by automatic time control, the beam 21 first lifting the moulds 55 and then moving the side moulds 11, 11a outwardly and then, when a dog'53 has moved along a slot 18, the lasts 19 are moved away from the central side mould member 2. The lasts with the moulded shoes are then removed along the track 74. The mould members are provided with overflow passages 70a, (706, not shown) 70c, 70d and overflow chambers 69a, (69b and 69c not shown) and 69d. The size of the overflow passages is arranged to be such that the resistance of the rubber in the passages prevents the pressure developed in the mould from being reduced.