GB621322A - Improvements in or relating to shoe-upper conforming machines - Google Patents

Abstract

621,322. Lasting-machines. BRITISH UNITED SHOE MACHINERY CO., Ltd., and CHOICE, F. C. Feb. 18, 1947, No. 4652. [Class 17 (i)] Detailed improvements are made in the lasting machine described in Specification 598,164 with a view to improving its performance. (a) The work engaging portions of the upper jaws of the three grippers are opened to an unusually wide angle, i.e. some 50 degrees relatively to the lower jaws before the commencement of the cycle of operations, to facilitate insertion therein of the margins of uppers of different materials and thickness, as they extend outwards at an angle from the last, when the shoe is presented to the machine. Relative movement of approach of the gripper jaws from wide open to gripping positions is performed in two stages by cam-operated mechanisms, the first stage which is performed 'by an auxiliary closing mechanism after the lasting margin has been placed in the jaws closing them to a position similar to that occupied by the jaws of the earlier machine after which, and after the machine has been started into power operation, the upper jaws are closed on the work and the grippers moved bodily to tension the upper by means similar to those employed in the earlier machine. (b) Stripping devices having prong-like portions 197, Fig. 10, pivotally mounted in shrouding recesses 199 in the lower jaws 15 of the side grippers, are forced from their recesses, as the grippers are returned in opened position of the jaws to initial position after completing an operation, to strip upper material which may adhere to the lower jaws due to adhesive from a toe stiffener being present thereon. (c) The return movement of the shoepositioning fingers to operative position is delayed, compared to the earlier machine, by a latch device, which is released, when the other parts of the machine reach their final position of rest, to enable the operator to remove the shoe from the machine without danger of fouling the fingers. (d) Disturbance of the last in the shoe upper in the machine due to movement at an early stage in the cycle of operations, longitudinally of the shoe, of the toe end gripper is prevented by providing means, in addition to and independent of those which move the gripper heightwise of the shoe to impart tension to the upper, which impart to the gripper movement away from the last with a component lengthwise of the last after a considerable portion of the upper tensioning movement of the gripper heightwise of the last has taken place. A heel end abutment engages the upper after the side grippers have started to tension the upper to reduce the tendency to forward thrust.