Patent GB-388778-A (GB)
Title: Improvements in or relating to machines for attaching heels to shoes
IPC: A43D79/00
Filed: 1931-08-26
Abstract: 388,778. Screwing heels to shoes. BRITISH UNITED SHOE MACHINERY CO., Ltd., Union Works, Belgrave Road, Leicester.-(United Shoe Machinery Corporation ; 140, Federal Street, Boston, U.S.A.) Aug. 26, 1931, No. 23956. [Class 83 (iii).] Drilling- machines; countersinks.-A machine for inserting a heel-securing screw in a shoe or the like has a work support and countersinking tool the former having freedom of movement transversely to the axis of the tool to permit a previously made hole in the heel-seat to be centred, and permitting accommodation of shoes with different angles between tread-face and heel-seat. The work-table 24, covered with non- slip material 26 is made in two parts, the lower part, bent twice at right-angles to accommodate a ball bearing 50 and bush 46, is attached by bolt and slot means 60 to the upper part so that the latter is capable of limited movement in a plane parallel to its face, keepers 54, Fig. 8, pivoted about pins 58 and drawn together by springs 56 bear against the bush 46 and tend to return it to a central position ; movement of the work-table in a plane perpendicular to its face is provided for by a spherical joint 32, Fig. 6, and guide pin 38, an adjustable stop 40 allowing the table to be set at the required inclination. The pillar 30, carrying the worktable, has rack teeth at its lower end engaged by a pinion 92 mounted in a boss 80 which is rigidly fastened by a nut 88 to a partially screwed sleeve 82 through which the pillar passes ; the pinion 92 is rotated to adjust the height of the work-table by a graduated drum 98 which is normally pinned to the boss 80 but may be disengaged for rotation by drawing it to the right, Fig. 1, against spring pressure. The threads 110 on the sleeve 82 are of quick pitch so that depression of the work-table and consequently the sleeve and attached boss 80, rotates a nut 112 mounted between thrust bearings in a bracket 74, the movement being resisted by a spring 76 coiled around a bolt in the bracket 74 and attached to the boss 80 to force it upwards. Locking of the nut 112 against rotation in any position locks also the sleeve and worktable against vertical movement, this is effected by a spring-pressed plunger 118 which is normally forced into engagement with teeth on the nut but can be held retracted by a slotted latch 124 reciprocated vertically by a bell crank 144 and plunger 148. T h e whole of the abovedescribed parts are carried by a slide 70 which moves in guides in the machine frame 20 and is connected by a pin 154 and slotted lugs 152 to a cranked lever 156 and toggle links 162, 164 ; a latch 190 on the pin 154 transmits t h e lifting movement to the slide for the countersinking operation, but on contacting with a stop 184 releases the slide and allows it to fall the length of the slots 153, simultaneously, or a trifle before, pressing in the plunger 148 to lower the latch 124 and lock the nut 112, Fig. 6 ; theslide normally rests in its lowermost position on a spring buffer 151 and in this position a bell crank 134 has been rotated anticlockwise to retract the plunger 118 and unlock the nut 112. A pedal 180, Fig. 1, on being depressed pulls down the rod 174 and a stop 172 coacts with a campiece 168 on the toggle-joint forcing the lever 160 around in a clockwise direction and thus raising the slide 70 as previously described, further movement of the pedal which is ineffective on the slide since the stop 172 rides over the cam-piece, serves to operate the screwdriving t o o l described below. A head casting 196 bolted to the upper frame of the machine carries the driving elements for the tools, these comprise worm 234, Fig. 9, driven from a belt and self-contained motor 240,.spiral wheels 230, 232 driving through yielding dog-clutch 221, 224 the screwdriver 210 and wheels 254, 250 driving the countersinking tool 242. The shaft 200 to which the screwdriver is attached extends upwardly and is engaged by the lever 204 forming part of a linkage controlled by the movement of the pedal rod 174. A secondary lever 297, Fig. 1, transverse to those previously described, is rotated upon upward movement of lever 204 and serves to depress a rod 294 each time the operating pedal is raised. This rod passes into a bin 282, Fig. 1, for screws, the bottom of which is rotated by gearing from the worm shaft 236, and forms a channel with the walls into which the screws drop and are fed around ; a rotary brush serves to clear the channel of improperly located screws at the entering end of a segmental guard, the screws are led into a spring sleeve through which they are pushed by the descending rod 294 finally falling through a pipe 290 into the hollow machine spindle via the opening 292 taking up the position shown in Fig. 9. The sequence of operations is thus initial depression of pedal giving upward motion of slide 70 and floating work-table; automatic positioning of the table by the rotating split countersink too], feed of, which is limited by the adjustable sleevepiece 19 ; release of latch 190 allowing the slide to drop sufficiently for the countersinking tool to be opened by the descending screw and driver and simultaneous locking of the worktable ; further depression of pedal effects feed of screwdriver until the driving clutch slips and final 'release of pedal feeds a screw into position for the next operation. Specification 186,376, [Class 83 (iii), Metals, Cutting], is referred to.