Patent GB-403297-A (GB)
Title: Improvements in or relating to shoe-end lasting machines
IPC: A43D21/12
Filed: 1933-05-29
Abstract: 403,297. Boot-making machines. NOLLESCHE WERKE KOMMANDIT-GES., Weissenfels, Germany. May 29, 1933, No. 15500. Convention date, June 6, 1932. [Class 17 (i).] Lasting.-In a shoe-end-lasting machine wipers are actuated by hydraulic means, pressure fluid being continuously circulated by a constantly running pump through cylinders accommodating plungers connected to the wipers. A treadle operated valve causes the plungers to drive the wipers to operative position, the valve being automatically returned after the completion of the wiping movement. Preferably, the tacking mechanism is mechanically operated. A last is supported by a heel post 1 and a longitudinally and vertically adjustable toe rest 2 carried by curved guides so that either end of the shoe may be brought into the plane of the wipers. The shoe support is slidable horizontally to and from the wipers under the control of a ring 10, secured to a plunger 11 backed by a spring. The slide is supported by a plunger 9 which can be depressed by a handle 13 against the action of a spring 15, the latter maintaining the work pressed upwards against a stop 23 adjustable vertically by rack and pinion gearing locked by a pawl. A constantly running pump 16 withdraws oil from a chamber 17 and delivers to pipes 20, 21, the pressure being adjustable by a hand wheel 44 controlling the strength of a spring behind a relief valve. The pipe 20 leads fluid below the plunger 9 and the pipe 21 leads to the cylinder 11 whence a port 74 opens between heads of a valve 6 co-operating with ports 71, 68 on opposite sides of wiper plungers 28. Ports 72, 73 connect to a return pipe 70. The valve 36 is linked to a bell-crank lever 38 actuated by a treadle 41 and also linked to a lever 47 co-operating with a device 85 for driving tacking mechanism. This mechanism comprises an eccentric 53 rocking a lever 55 actuating a plate 59 engaging above driver rods and a follower plate 62 for returning the rods after tacks have been driven. The device 85 is a spring plunger sliding axially in a member loose on a driven shaft 76 and formed with a spur wheel 51 gearing with a spur wheel driving the eccentric. The free end of the lever 47 is wedge shaped and normally holds the plunger retracted, with its spur wheel at rest. On depression of the treadle, the plunger is freed, locks the spur wheel to the shaft 76 and the eccentric is driven until an arm on the eccentric shaft returns the lever 47 to normal position to engage and withdraw the plunger 85 when this reaches it. The plungers 28 are linked to wipers 32 of which that at the shoe end moves in a straight path, and those at the sides are guided in are-shaped paths about a point 33. The foremost of the side wipers may be locked in inoperative position by pins 74<1>. A leather band 35 surrounds the shoe end, and, on reaching this, abutments 34 on the wipers act as stops to prevent further movement. The inner and outer ends of the cylinders of the wiper plungers are connected by semi-circular channels 71<1>, 68<1> respectively, and the plunger for the end wiper is backed by a spring, so that this plunger is returned last, the channel 72 being then opened to exhaust. The lever 55 also actuates a rack 64 driving the tack drum 66 as usual.