Patent GB-112977-A (GB)
Title: Improvements in or relating to Machines for Performing Finishing or other Operations on Boot or Shoe Bottoms.
IPC: A43D87/00
Filed: 1917-01-30
Abstract: 112,977. British United Shoe Machinery Co., (United Shoe Machinery Co.). Jan. 30, 1917. Trimming.-Machines for performing finishing or other operations on boot and shoe bottoms, and particularly machines for trimming attached heels, in which there is provision for movement of approach between a work-support and a device engaging a guiding-groove, such as the shoe crease, are arranged so that the device becomes seated in the groove by virtue of automatic relative movement between the work-support and the device in a direction transverse to the direction of movement of approach and to the groove. The invention is described as applied to a machine of the type described in Specification 15092/08, which, however, is fitted with a work-support constructed to manipulate the shoe so that the cutter trims the entire heel edge. This machine comprises a cutter 8 mounted on an horizontal shaft 6, and a crease or counter guide 10 which is held by a spring 12 against the outer end of the cutter: the usual top-lift guide is replaced by a guide 14 comprising an L-shaped plate having a guiding face curved to conform to the path of rotation of the cutter and a shank secured to the usual adjusting-device 15. The shoe is clamped in a yoke-shaped frame comprising a bracket 16, member 18, and a rigid bar 20, in a vertical portion of which is mounted on ball bearings a rotatable top-lift plate 24. A sleeve 26 is mounted for rotative and sliding movements in the member 18 and houses a sliding plunger 28, which carries adjustably a last pin 30 and is formed with an enlargement 34 to which are pivoted side clamps 37, 38 having secured to them strong leaf springs 39, 40. A spring 33 bears against the enlargement 34 and tends to force the plunger forwards with relation to the sleeve 26, which is adapted to be operated by a hand-lever 44. When this lever is swung to the right, Fig. 3, the plunger 28 and sleeve 26 move forward together until the end of the plunger is seated against the cone of the last, when the sleeve moves relatively to the plunger, compressing the spring 33, and causing inclines 41. 42 on the sleeve to spread the springs 39. 40 so that the side clamps 37, 38 are pressed firmly against the shoe. The hand-lever 44 is provided with a locking-device 52, 49, and a. release 54. The member 18 is made in two parts relatively adjustable to compensate for variations in heights of the lasts. The bracket 16 is carried by a slide 74 mounted on ball bearings in the upper end of a vertical slide 60. which is adapted to be reciprocated through links 64, 68 from a cam 70 on a shaft 72. This shaft is driven by a worm and wheel 140, 142, from a shaft 144 carried in a bracket 148, which is adapted to be rocked about a pivot 150 by toggle mechanism 152. When a treadle 158 is depressed, the worm and wheel are moved into gear, but after a single revolution of the shaft 72, the toggle is broken and the worm drops away from the wheel. The slide 74 is adapted to be moved to carry the clamped shoe towards the cutter 8 by a strong adjustable spring, and in the opposite direction by a cam-actuated lever 82 engaging a roll 88 carried by the slide; the lever 82 may, however, be actuated by a hand-lever 89 to carry the shoe away from the cutter at any desired time. To compensate for the difference in pitch between the rear end and sides of the heel, the bracket 16 is provided with a curved extension 90 supported on ball bearings in a corresponding extension 91 of the slide 74. These extensions are curved about a vertical axis adapted to be brought into alinement with the face of the guide 14 during the trimming operation, and the clamping-mechanism is arranged, and provided with adjustments, to support the shoe with the edge of the top lift always substantially in this axis, so that the heel is enabled to adjust itself to the cutter in accordance with any variations in pitch; a spring 92 tends to swing the bracket 16 about this axis to move the heel towards the cutter through an amount limited by an adjustable stop 96. The mechanism above described provides means for trimming the sides of the heel, but for trimming the rear end it is necessary to rotate the clamping-devices through 180 degrees. For this purpose, a bevel-gear 102 splined to the sleeve 26 gears with a wheel 104 mounted in the member 18 and connected by a universal joint 110 to a section 108 of a telescopic shaft, the main portion 106 of which is similarly connected to a bevelwheel 114 mounted in a casing 116. The wheel 114 meshes with a sector 118 pivoted on a shaft 120 and carrying a roll 122 engaging a cam track 124 in a plate 126 bolted to the side of the stationary jack frame. The casing 116 is secured to the slide 60 so that, as this slide is raised, the roll 122 travels along its track 124, and when it reaches the curved part it swings the sector 118 and so drives the various gears, which rotate the shoe clamp. In order that the guide 10, Fig. 3, may automatically find the heel seat crease preparatory to the trimming operation, its shank has a pin-and-slot connexion with an arm 132 adjustably clamped to a slide rod 130, which is adapted to be actuated by a pivoted lever 134 having a curved lower end positioned in the path of a bolt adjustably threaded into the slide 60. In the lowest position of this slide, the bolt presses against the lever 134 with the result that the guide 10 is held away from the cutter, and is so held as. the slide rises until the shoe counter is about to contact with the guide, when the bolt releases the lever 134 and the spring 12 forces the guide 10 towards the cutter and causes it to engage the heel seat crease.