Patent GB-105355-A (GB)
IPC: D05B39/00
Abstract: 105,355. Mayo, B. F. March 7, 1916. Sewing-machines; feed by clamps; work supports; marking work for sewing.-The parts of a shoe upper, such as the toe cap and vamp or the vamp and quarter, are first positioned in proper relationship and are held in this relationship by clamping-means while being stitched together by machine. In one form of the invention, Figs. 1, 2, and 3, for use with toe caps and vamps, the positioning and clamping device forms an attachment to the work-plate 1 of a sewing-machine, the usual feed-dog of which is indicated at 83. A plate 8 is supported for lateral adjustment beneath the plate 1, and beneath it is yieldingly supported a frame 3 formed with arms 5, 22, 25 carrying fixed gauge pins 9, 19, 23 and adjustable gauze pins 7, 21, which normally project slightly above the plate 1; the pin 19 is screw-threaded, so that it may be removed when positioning full-length vamps. Between the frame 3 and the plate 8 is a slidable depressor bar 53 provided with camprojections 55 to engage the arms 5, 22, 25, and adapted to be operated by a handle 27 or from a treadle. Above the work-plate is located a spring- controlled arm 41 adjustably carrying a gauge bar 42, which is formed with projections 48 to engage the rear end of the toe cap; the arm 41 is pivotally supported on a bracket 37 end is operatively connected by a rod 57 to the bar 53. The clamping- device comprises hinged plates 63, 65, of which the lower plate 63 rests on the work-plate 1 and is provided with openings for the pins 7, 9, 19; the plate may also be provided with an end gauge 85. The plate 65 has secured to it brackets 71 to support a curved guide 69, and is flanged at its edge to form a second and concentric guide 73. The plate 63 is formed with a boss 72 connected for a limited amount of pivotal movement by a screw stud 77 to an arm 76, which is slotted at 80 to receive a stud 81 projecting from the workplate and carrying a confining-washer 82; a spring 84 connected to the stud 81 and the forward part of the arm 76 normally acts to withdraw the clamp from operative position. The clamping- plates 63, 65 are adapted to be closed by a cam 75 provided with a handle 79, which, when the sewing is completed, is adapted to engage an adjustable stud 70 so as automatically to open the clamp. In the use of the device, a vamp V is first located by the pins 19, 21, 23, and a toe cap T is then placed on the vamp and positioned by the pins 7, 9 and the projections 48 on the arm 41, which is swung forwards by its spring on the release of the handle 27. The clamp is then closed and the depressor bar moved rearwards to cause the cam-projections 55 to lower the frame 3 and the positioning-pins, and to swing the arm 41 to the rear, after which the operator pulls the clamp towards him, stretching the spring 84, and introduces the end of the flange 73 in a slot formed by two members 119, 120, Figs. 5 and 7, which, together with two antifriction wheels 123 arranged to bear upon the clamp, constitute the presserfoot of the machine. In these Figures, a modified form of clamp, to be described, is shown, having a guiding-bar 101 and a flange 99 corresponding to the bar 69 and flange 73. The bar 69 is also placed in engagement with a grooved feed-roll 125 fast on a shaft 127, which is driven intermittently from the main shaft of the machine. The work is fed by the combined action of the feed-dog 83 and the feed-roll 125, and is guided by the flange 73 and the bar 69, the clamp swinging about the stud 81 as a centre. Two pins 141, 142 are supported so as to extend adjacent to the roll 125, and the action of this roll 125, which feeds the work faster than the dog 83, tends to keep the bar 69 in sliding contact with the pin 141. If the feeding movement imparted by the roll exceeds the desired amount, the bar is forced against the pin with sufficient pressure to lift it out of the groove in the roll, which then slips on the bar until the normal feeding movement is resumed. When the flange 73 passes from between the members 119, 120, the spring 84 automatically withdraws the clamp, which is opened by the engagement of the stud 70 with the handle 79. In a modified construction, Fig. 4, a work table 87, independent of the sewing-machine, carries adjustable pins 89 for positioning the vamp, and pins 90 to act in conjunction with gauge arms 93 for positioning the toe-cap; these arms are pivoted in the slotted ends of an adjustable bar 91 and are normally held by springs 95 in the position shown in dotted lines. The clamp comprises a curved spring bar 105 carrying on its lower member a curved and preferably resilient plate 106 arranged with its concave side uppermost, and a co-operating plate 97 which supports two spaced staples 111 and a pin 113. A grooved head 115 is located between the staples and provided with guide-pins 109 engaging between the legs of the staples and with a slot to receive the pin 113. A cam 107 is connected to the head 115 by a transverse pin 110, which also serves as a stop for the upper member of the spring bar 105. The plate 97 is bent to form the guiding-flange 99 above referred to, and carries brackets 103 to support the curved guide-bar 101. After the upper parts have been positioned and clamped, the clamp is transferred to the sewing-machine with the guides 99, 101 arranged as described above. In another modification, Figs. 9 to 12, for positioning and clamping a cylinder vamp and quarter, a pedestal 147 supports a form comprising a fixed forepart 149 and a slidable heel part 151 operable through a link 159 and bell-crank 157 from a spring-controlled treadle rod 161. The quarters Q are positioned with their lower edges resting on spring-pressed pins 165, which are arranged normally to project from openings in the sides of the heel part, while the eyelets of the quarters are engaged with pins 175 carried by slidable blocks 177 mounted on reversely threaded screws 179 in a frame 174. The form is extended, and a vamp V with its heel portion sewed up is placed over the quarters with its lower edge resting on a bar 169 adjustably mounted on a threaded rod 167 rigidly connected to the heel part. The vamp is then pulled from the toe to cause it to hug the form closely and to force inwards the pins 165, and clamping-plates 187, 189 are then placed over the vamp and quarters, as shown in Fig. 10. These plates are made to overlap, and are connected together for adjustment by bolts 193 entering slots 191; they carry brackets to support a telescopic guide-bar 195, corresponding to the bar 69 of the first construction, and a divided overlapping flange 197 corresponding to the flange 73. The plates are secured in adjusted position by cammembers 203 in a. similar manner to that described in the second construction, and the clamped work is then transferred to the sewing-machine. The forepart of the form may be provided with an arm 153, to which is adjustably bolted a clamp 183 carrying spaced padded arms 185 for engaging the lower front portions of the quarters of a button boot.