Patent GB-158665-A (GB)
Title: Improvements in or relating to automatic boot or shoe machines
IPC: A43D95/20
Filed: 1919-11-07
Abstract: 158,665. British United Shoe Machinery Co., Ltd., (United Shoe Machinery Corporation). Nov. 7, 1919. Edge-setting.-Relates to burnishing or edgesetting machines and other machines of the class in which a shoe held on a jack and a tool are given an automatic relative traversing movement to transfer the point of operation round the work, during which movement their relative aspect is automatically varied in accordance with the shape of the shoe bottom, and consists in the provision of means automatically to control the pressure between the tool and the shoe at all points along the shoe margin. The invention is described as applied to an edge-setting machine of the kind described in Specification 14696/08. According to the present invention, the edge-setting tool 10, Fig. 1, is held to the work by a spring 37 the effective pressure of which, however, is controlled by a stronger spring 29, Fig. 2, which is adjustably connected at one end to an arm 27 extending from a shaft 25 and at its other end to an arm 30 projecting from a sleeve 31 loosely mounted on the shaft 25. The sleeve 31 is formed with arms 31<*> connected bv links 32 to a plunger 33 which extends into a dash pot 34. Fig. 1, at its lower end and is secured to a rod 35 extending slidably through an abutment 36 pivotally mounted on the usual pressure lever 14; the spring 37 encircles the rod 35 between the abutment 36 and a collar 38. Also loosely mounted on a shaft is a second sleeve 40, Fig. 2, having one arm 41 carrying a cam roll 42 in engagement with a cam 23, which is supported through a universal joint connection 22 from the jack shaft 20, Fig. 1', and a second arm 43, Fig. 2, extending towards and opposite to an arm 44 projecting from the sleeve 31; the arm 44 is provided with an adjustable stud 45. In operation, movement of a starting lever 26 connected to one end of the shaft 25 causes the spring 29 to be placed under increased tension and, through the connections described, places the spring 37 under compression to produce pressure between the work and tool. As the jack shaft 20 rotates, the cam 23 causes the arm 43 to act through the arm 44 to turn the sleeve 31 against the stress of the spring 29, thereby relieving the pressure of the spring 37 at such points, for instance, as when sharply-curved portions of the sole' edge are presented to the tool 10. The cam 23 may be designed to be operative continuously, or only at isolated intervals. In another construction, according to the invention, the pressure lever 14, Fig. 4, is connected by a toothed segment 52 to a rack 53 actuated from a piston 54, which moves in a cylinder 55 mounted on a plunger 56; the plunger is formed with a reduced portion 58 where it passes through a guide or casing 57, and a channel 59 leads from the outer surface of the plunger to the cylinder 55. Adjacent the reduced portion 58 are located inlet and outlet pipes 60, 61, Fig. 5, arranged so that fluid, preferably oil under pressure from a head or pump, will flow freely into the space surrounding the reduced portion 58 and through the channel 59 into the cylinder 55. The outlet pipe opens into a chamber above a valve 62, which is normally held raised against its seat by an adjustable spring 64. The starting lever 26 is connected by a link 69, Fig. 4, with a collar 70 on the plunger 56, and between the collar 70 and a shoulder 71 on the casing 57 is arranged a spring 72; the lower end of the plunger 56 may project into a dash pot. With this construction, the valve 62 will open and close in accordance with the slight in-and-out movements of the lever 14 as the work is traversed past the tool, and the pressure of the tool on the work will be kept constant. In order, however, that the pressure may be modified or relieved at any desired part of the work, cams 81, Fig. 6, adjustably mounted on a rod 73 are arranged to contact with the upper end of the valve stem to open the valve. The rod 73 is reciprocated by connections 74, 75, 76, 79 with an eccentric strap 78 surrounding the jack shaft 20. The cams 81 are set to modify or entirely to relieve. the pressure of the tool as it passes along portions of the sole edge where the shank and forepart merge into each other at the inside and outside of the tread respectively.