| 摘要 |
956,475. Moulding soles on to uppers. INTERNATIONAL VULCANIZING CORPORATION. Jan. 20, 1961 [Jan. 28, 1960; Sept. 16, 1960], No. 2413/61. Heading A3B. [Also in Division B5] An apparatus for moulding a sole on to an upper comprises a last having an upper U thereon, an open mould 8 having an injection opening, means for mounting the upper on the mould for relative movement thereto and means for resisting the relative movement. Means are provided for injecting a sole forming composition through the injection opening into the mould at a pressure above that of the means resisting relative movement and also means, e.g. a switch S, automatically operable by a predetermined relative movement of the last and mould to terminate injection. A constant pressure is maintained on the sole by the means resisting relative movement during setting. In the construction shown the mould is mounted and fixed on a table 16. The mould which is laterally movable has four gauge blocks 40 for centralising the lasted upper U in the mould. An air cylinder 18, the piston pressure of which is controlled by a regulator R and valve V, is mounted vertically above the table and mould. The two rods 22 and 24 protruding from the cylinder are extensions of the piston the former carrying a bar 26 to which is attached a heel abutment and a toe hold-down 30 while the latter is threaded at 36 to carry on adjusting nut 38 which limits the downward movement of the piston. The lasted upper is engaged by the heel abutment 28 of the bar 26 and the toe hold-down 30 and the plasticized material is injected into the mould through a nozzle 44 by a screw 48 rotated by a motor M. The screw is situated in a barrel 46 which is heated by a jacket 50 surrounding it. The pressure of the plasticized material lifts the lasted upper from the rim of the mould a predetermined amount whence the injection is cut off by the switch S engaging on a projection of the apparatus. When the mould is filled a tough skin is formed adjacent the wall of the mould. This skin does not rupture when the last lifts from the rim of the mould. The sole is then solidified by heating or cooling the mould. In a modification the lasted upper is fixed with respect to the mould and the base of the mould is free to move, the movement vertically being controlled by an air cylinder as above or by a spring. Also a last with a sprung base is disclosed, the base giving the predetermined movement while the main part of the last remains fixed with respect to the mould. Specification 763,847 is referred to.
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