Patent GB-419944-A (GB)
Title: Improvements in or relating to shoe bottom levelling machines
IPC: A43D89/00
Filed: 1933-05-17
Abstract: 419,944. Boot - making machines. BRITISH UNITED SHOE MACHINERY CO., Belgrave Road, Leicester.-(United Shoe Machinery Corporation ; 140, Federal Street, Boston, U.S.A.) May 17, 1933, No. 14218. [Class 17 (i).] Sole -levelling.-In a machine of the kind wherein a shoe on a jack is oscillated under a levelling roll, manual means are provided for tipping the roll at will, for lifting the roll from the shoe at will, and for reversing the oscillation of the jack at any point. When the jack is allowed to complete its forward swing, the roll is raised from the shoe when the toe end is reached and is simultaneously withdrawn to permit the work to be changed, these movements being reversed when the machine is restarted with a new work-piece in position. This lifting and lowering of the roll prevent excessive bending of the margin of the toe end of the sole. An improved shoe support is provided, preventing damage to the upper at the toe end and relieving the last of excessive strains at the heel end. The jack is of the kind described in Specification 104,728, [Class 17 (i)], with a toe post 26 and heel post 30 independently pivoted to the frame at 28 and adjusted for length of shoe by a hand-wheel 34. The last pin is tipped by a link 46, and a waist saddle or shank strap 48 is provided as described in Specification 103,849, [Class 17 (i)], a jacking handle 50 depressing the saddle when this is used or tipping the last pin according to the position of a latch member 76 as described in Specification 269,114, [Class 17 (i)]. The jack is oscillated by a cam track 90 actuating a lever 102 pivoted to the frame and formed with a curved slot engaging a block at one end of a link 100 having at its other end a block engaging a similar slot in an arm 98 fixed to the toe post. The centre of the link 100 is pivoted to a link 118 pivoted to the frame, and its upper end is adjustably linked to a lever 122 pivoted to the arm 98 and linked to an arm extending from the heel post. In operation, the adjustment of the jack for size of shoe by the handle 34 shifts the ends of the link 100 along the curved slots to cause the oscillation produced by the cam 90 to correspond to the length of the shoe. This automatic adjustment may be varied for style of shoe by a handwheel 148 geared to the adjustable link 132. The roll 24 is centralized by springs on a rod 159 supported by a yoke slidable lengthwise of the shoe in a carrier 162, the yoke being adjustably secured to a rod 174 linked to a lever 182 actuated by toggle links 188, 190 normally straightened by a spring 192, but broken when the jack is in its foremost position by a cam-actuated lever 198. The carrier 162 is axially rotatable in an arm 168 pivoted at 170, segment gears 264, 266 actuated by an arm 254, link 246 and handle 270 being provided for tipping the roll when desired. Normally, the roll is depressed by a spring 214 connected by a link 220 to the arm 168 and to a lever 216 engaging a cam shaped to increase the pressure at the shank of the shoe. For raising the roll when the toe end of the shoe is reached a rod 206 is actuated by the cam-operated lever 198. For lifting the roll from the shoe at any other desired time a treadle 280 is connected by a rod 278 to a lever 274 pivoted to the frame and controlling a gripping device comprising a plurality of plates 272 apertured for passage of the rod 220, resting at their forward ends on a lug 288 on the frame, against which they are held by a spring plunger 290, and clamped at their rear ends between a lug and a screw on the lever. On depression of the treadle, the plates bind on the rod 220 and lift the roll. The cam shaft 94 is driven by a worm 294 on a shaft on which clutch members 328, 330 are splined, these members co-operating with friction clutches 298, 300 driven in opposite directions by gear wheels 310, 312. The members 328, 330 are carried by a sleeve 332 moved endwise by a lever 336 actuated by a rod 342, the sleeve being normally centralized, so that both the clutches are free, by springs 374, 376 threaded over the rod between collars thereon and a fixed abutment 378. The rod 342 is connected to a hand lever 358 for starting, stopping and reversing. To stop the machine when the jack has swung to its limit in either direction, a pin 384 on the worm wheel co-operates with bell-crank lever 386 resiliently connected to the rod 342, which lever shifts the sleeve 332 to central position when it is engaged by the pin. When the sleeve is in this position a brake band 410 engages a drum 412 on the shaft, the brake being applied by toggle links 430, 432 actuated by a pin 440 on a sleeve clamped to the rod 342. Movement of the rod in either direction from that shown breaks the toggle and releases the brake. The heel end of the last is supported by a plate 40 loosely surrounding the last pin and provided with side walls with curved lower edges resting on curved shoulders of the block carrying the last pin. The toe rest 454 is self-adjusting on rollers 462 in an arcuate guideway in a block 450 vertically adjustable by a wedge 452 traversed by a worm 451. A second worm 448 adjusts the base of the block in an arcuate guideway at the top of the post 26. In operation, a shoe having been positioned, the jack handle 50 is depressed and the lever 360 is pushed forward. As the cam shaft commences to rotate, the roll 24 advances and descends on to the toe portion of the sole, the shoe then swinging under the roll. At any point the operator may reverse the motion, tip the roll by the handle 270 or lift the roll by the treadle ; he may operate on a particular portion by a plurality of short movements. When the levelling is complete, the jack is allowed to move fully forwardly, when the roll is raised and retracted and the work may be changed.