GB190927350A - Improvements in or relating to Shoe Jacks for Levelling and Laying Machines. - Google Patents

Abstract

27,350. Plant, T. G. Nov. 24. Sole-laying; sole-levelling.-A jack or worksupport for sole levelling or laying machines, particularly one of the type that includes a last, is constructed so that the pressure may be evenly distributed across the sole throughout its length, or may be applied with greater force on one side or the other, as desired; it also includes an automatically-adjustable toe-rest, and means for moving the last away from the rest when the levelling or like operation is completed. The last consists of two portions 6, 30, the former of which is removably mounted on a head 11 at the upper end of a standard 5, which rises from a base 22 adjustable in slides in a cradle 1. The heel part 30 is also removable, and is adapted to be moved yieldingly to expand the shoe by means of an operating- handle 20. The cradle 1 is supported in a frame 2, which is mounted to slide in ways 2<1> in a bed 3 to carry the jack towards and away from the levelling or like mechanism. As it is moved into operative position, a cam-surface 58 secured to the bed 3 will, if the handle 20 has not been fully depressed, engage a nose 57 on the end of the handle and move this into its proper position, in which it is locked. As the jack moves outwards after the levelling or like operation, the handle 20 is automatically released to allow the heel part 30 of the last to collapse, and at the same time the head 11 is actuated automatically to throw the toe part of the last upwards, for convenience in removing the shoe. The toe of the shoe is supported on a padded rest 10 carried by a head 62, which is pivotally mounted to allow the rest to accommodate itself to the work. The toe support as a whole can be adjusted towards and away from the standard 5; it can also yieldingly adjust itself in height to the nature of the work. As the jack moves into operative posi. tion, a spring-actuated wedge 73 is automatically moved under the toe-support, to form a rigid abutment for the toe of the shoe while it is being levelled. The wedge is automatically withdrawn as the jack returns after the levelling operation. In order that the pressure to which the shoe is subjected may be distributed over the sole in any desired way, the pivotal supports of the cradle 1 are mounted so that they can be shifted laterally relatively to the direction of application of the pressure, such movement being effected without tilting or swinging the cradle. The arms of the cradle 1 are formed with heads 102, each of which rests on a slide 103 pivoted on a pin 105 projecting from a second slide 104, which is adapted to move on rollers 107 in a track 106 rigidly secured to the frame 2. The pressure of the jack is transmitted through the pins 105 to the frame 2, and the line connecting these pins forms the centre line of the jack. To vary the distribution of the pressure, the position of the pins is varied by shifting the slides 104 relatively to the frame 2 and the cradle. For this purpose, each slide is engaged by a pivoted lever 112, the lower end of which is connected to a slide 118 carrying a roller 119 working in a cam 116 secured to the bed 3. The shape of this cam determines the position of the centre line along which the pressure is applied.