Patent GB-724215-A (GB)
Title: Improvements in or relating to machines for performing lasting and analogous operations on shoe parts
IPC: A43D25/06
Filed: 1952-05-08
Abstract: <PICT:0724215/III/1> <PICT:0724215/III/2> A machine for lasting with the aid of adhesive has means for tensioning a lasting margin C progressively at different positions along the margin of a shoe bottom, a nozzle 300 for applying adhesive to the shoe bottom, and means for moving the nozzle to and fro to cause the adhesive to lie in a wavy line Z along the margin as the shoe bottom is fed along during the lasting operation.  Means for pressing against the lasted margin, and means for varying the width of the band of adhesive are included. The machine is generally similar to those described in 598,216 and 623,347, [both in Group VII], having upper tensioning means comprising a rear jaw 10 and front jaw 12, a shoe bottom rest 14, a presser foot 16, a feed retaining finger 18, and an edge gauge roll 20.  The nozzle 300, located between the gripper 10, 12 and the presser feed foot 16, is secured to an arm 302 extending from a member 304, 306, 308 mounted for reciprocation about the axis X, about which the rest 14 is also pivoted by means of the treadle-operated rod 30.  When the treadle is depressed, rod 30 moves downwardly pulling link 354 which pivots bell-crank 352 and moves rod 350 so that a fork 348 on the latter engages a block 346 and straightens the toggle 332, 334.  Arm 302 and nozzle 300 are then reciprocated by the eccentric 338 on the main shaft 340 acting through the eccentric strap 336, links 334, 332, bell-crank 324, link 314, and lever arm 312 on part 308.  When the treadle is released, link 354 is lifted by the treadle spring and moves rod 350 whereupon spring 342 breaks the toggle, so that the eccentric does not move bell-crank 324.  Spring 360 swings the nozzle to an idle position determined by stop screw 364.  The amplitude of the reciprocation of arm 302 and nozzle 300 is determined by adjusting the position of the end of link 314 in the arcuate slot 308 in bell-crank 324 and clamping by nut 320.  The centre of curvature of slot 318, when the parts are as in Fig. 1, is at the pivot of 314 and 312, hence the nozzle always moves inwardly to the same position relatively to the edge of the shoe, and the inner edge of the band of adhesive is always located close to the edge of the shoe.  The nozzle reciprocates in timed relation to the other operating parts, thus the nozzle is outermost, as shown in solid lines in Fig. 3, at the conclusion of tensioning and as the presser foot descends, and innermost, shown in dotted lines, at completion of the feeding movement.  Heated adhesive is applied to the nozzle through 410, 406, 412 from container 414 by means of a pump driven from shaft 340 through telescopic shaft 415 and belt 417, a by-pass valve, controlled by lever 416 and rod 418 connected to the treadle, being closed when the treadle is depressed.  The flow of adhesive is heated by a low voltage coil 420.  Alternatively, the adhesive may be dispensed as in Specification 618,372.  Specification 613,393, [Group VII], also is referred to in the Provisional Specification.