Patent GB-761992-A (GB)
Title: Improvements in or relating to machines suitable for trimming the margins of shoe upper materials
IPC: A43D49/00
Filed: 1953-11-03
Abstract: 761,992. Trimming shoe upper margins. BRITISH UNITED SHOE MACHINERY CO., Ltd., CHOICE, F. C., and PRATT, J. W. Nov. 1, 1954 [Nov. 3, 1953], No. 30292/53. Class 17 (1). A machine for trimming surplus marginal material from the toe portion of the upper of a shoe on a last has trimming means, a matrix on which the upper materials are supported as they are trimmed, means to spread toe portions of the materials across the matrix, and mechanism to cause the spreading means and the matrix to clamp the upper materials between them. The spreading means and matrix, while clamping the upper materials, are moved so as to apply tension thereto. The trimming means comprise disc knives which are moved lengthwise across the matrix towards the toe end. A pair of side spreaders are provided, each arranged to swing outwardly around the periphery of one of the disc knives and so turn portions of the material, at opposite sides of the shoe, outwardly across the matrix. In operation the inverted shoe is positioned against the toe gauge 26 and treadle 123 (not shown) depressed to cause the heel end abutment 14 and toe rest 16 to clamp the shoe against the bottom plate 12 and insole roll 28. Handle 192 is then used to trip the clutch and cause main shaft 6 to make a single revolution, whereupon the spreaders toe 30 move down to the insole and then move toeward while opening outwardly to spread the upper margins, the toe gauge moving rearwardly and roll 28 moving toewards to support the shoe as plate 18 wipes upwardly. Spreaders 30 then descend to clamp the upper margins against the matrix as the latter rises, thus assisting the wiper plate to tension the upper. As plate 18 completes upwiping side spreaders 32 descend to the insole and swing apart to spread the first portions of upper which are to be trimmed, and the knives 22, 24 descend into their operative positions. Thereafter the knives move toewardly. and rotate to trim the upper, the side spreaders 32 moving rectilinearly, remaining close to the operative portions of the associated knives, and holding against the matrix those portions of upper which are about to be trimmed. Trimming is completed when the main shaft has turned through 240 degrees, and the instrumentalities are returned by the time a single revolution has been completed, treadle 123 being then allowed to rise to release the trimmed shoe. Plate 12 is rockable on shaft 36, its operative position being determined by adjustment of a screw 42 which has a limiting stop 56, and may be held in a downward inoperative position. Toe rest 16 is adjusted forwardly and rearwardly by screw 72. Depression of treadle 123 acts through 110, 78, 64, and 60 to press the rest against the shoe, spring 84 limiting the pressure, and through latch 86 and locking lever 98 to lock the rest in shoe supporting position. Upward movement of the rest is limited if no shoe is present. The parts are returned by spring 124. The heel end abutment 14 is adjustable along slideways 128 pivoted to arm 138 rockable on shaft 140. When treadle 123 (not shown) is depressed it acts through 116, 162, to rock 154 and 138 until abutment 14 meets the shoe and presses it against gauge 26. Thereafter springs 160 yield to permit relative movement of 154 and 138. Eccentric 142 which supports arm 138 is adjusted by moving arm 148 to engage the spring pressed plunger 150 in one of a series of holes 152 in order to adjust the heightwise position of the abutment. The clutch cannot be tripped until springs 160 have yielded, when safety lever 168 drops on to latch 174 and engages notch 196 in the clutch link 184 with catch plate 198 on the trip handle 192. Additionally tripping of the clutch is prevented, when plate 12 is in its lowered position, by a safety lever 58 which then lies immediately above a lug 199 on trip handle 192. The interchangeable shearing block 20 is releasably mounted on slide 200 which is raised and lowered once each revolution of the main shaft under control of cam track 250, the upper position of the block being adjusted by means of a wedge which is controlled by screw 260. The changeable wiper plate 18, arranged within block 20, is releasably secured to carrier 272 which is adjustable on slide 200 by means of wedge 284 controlled by screw 290/292 to determine the relative positions of plate 18 and block 20 and hence the amount of upper to be trimmed. The upper surface of plate 18 forms the matrix 33 which is always below block 20 and may be shaped and positioned to skive the upper margin as well as trim the lining and toe puff. A slot in slide 200 accommodates the displaced gauge 26. The wiping movement of the plate 18 is regulated by adjustment of a screw 298 which engages slide 200. The head 9 carrying detachable knives 22, 24 is moved rearwardly and forwardly in the guideway 10 during one cycle under control of cam track 310 (not shown), the knives which are urged together by a spring 345 being first moved downwardly into the plane in which they move with the head 9 for trimming. When the head 9 moves along guideway 10 the knives are caused to rotate by pinions 348, 352, as the latter engage a double rack 358, the latter being pivoted so that it may rise and fall as the knives move relatively to head 9. The knife edges tend to pull outwardly away from the shoe those portions of the upper which they are trimming, paddles 365 on the knife shafts preventing trimmed scrap from wedging about the knives. The knives are adjusted so as to be close to each other by means of bolt 370 which causes the knife brackets to pivot about pins 342. Steel balls 373, whose positions are adjustable, provide a honing action. The knives are moved perpendicularly to guideway 10 under control of cam track 398 acting through 396, 394 yielding links 392, and bell crank 380. Carriage 427, carrying the adjustable gauge 26, roll 28, toe spreaders 30, and side spreaders 32, moves in and relatively to head 9 parallel to guideway 10 under control of cam track 434, and can move with head 9 when the latter is moved by cam track 310. Cylindrical ribs 438 on the shaped spreaders 30 are received in carriers 440 and these with spring loaded member 452 allow the flat undersurfaces of the spreaders and member 452 to present a continuous work-engaging surface to the shoe. Block 456 rocks on the spreader carrier 458 to allow the spreaders to accommodate themselves if the work is laterally tilted or uneven, and 458 rocks about 425 under the influence of cam 476 to raise the spreaders and under the influence of spring 478, which is adjusted by the helically-grooved member 482/483, to engage the spreaders with the work. Spreaders 30 are opened and closed under the influence of cam slot 510, acting through 508, 500, 496, 490, 446, when bell crank 500 moves together with carriage 427. Roll 28 is adjusted vertically on lever 534 by screw 540. The path of the roll 28, as carriage 427 moves rearwardly, is controlled, so that the roll continues to support the shoe, by means of cam surfaces 560, 558 acting through rolls 556, 554 to swing lever 534 about its pivot, the position of cam 560 being controlled by an eccentric 566 which is adjustable to one of a variety of positions by an arm 570. Cam 558 is shaped so that roll 28 is raised before it reaches the shearing block. Each side spreader 32 has a substantially triangular work-engaging undersurface which is bounded by concave edge 578 shaped to conform to the cutting edge of the knife,'wiping edge 579, and edge 580, and is substantially flat but curved up at the angle between 578/ 579 to enable the spreaders to ride over the upper. The plate-like portions of the spreaders overlap when the spreaders are closed, the left hand member entering a clearance slot in the right hand member. Each spreader 32 is pivotally linked to a lever 582 pivoted on carriage 427, levers 582 being connected by links 584 and ball joints 586 to a whiffletree 588 pivoted midway at 590 on a pivoted cam lever 594. The limited rocking of the whiffletree about 590 allows the spreaders to bear evenly on work whose thickness varies slightly from one side to the other. A spring plunger 597 urges the whiffletree against abutment 596, when the spreaders 32 move inwardly, so as to align the spreaders and ensure that the one engages slot 583 in the other. A roll on lever 594 engages a cam track 600 which acts to raise the spreaders or to permit spring 604 to engage the spreaders with the shoe. Movement of carriage 427 and head 9 moves spreaders 32 in the direction in which the knives move to trim. A presser block 615 (not shown) moves ahead of the knives to press down the upper on a median line between the spaced apart side spreaders. Swinging movement of the side spreaders is brought about by cam 638 (not shown) acting through roll 640, lever 634 pivoted on head 9, links 632, bell cranks 624, links 620, and triangular members 616 each of which is pivotally connected to a lever 582 and to a spreader 32. For trimming upper close to the " pull-over " tacks ears may be provided on plate 18 to form continuations of matrix 33 which support upper portions heelwards of those supported by the matrix. The sequence and timing of the operation of the different instrumentalities is described and illustrated. Specifications 530,981, 539,234, 622,357 and 668,204 are referred to.