Patent GB-158581-A (GB)
Title: Improvements in and relating to machines for use in the manufacture of lasts and shoes
IPC: A43D29/00
Filed: 1918-07-30
Abstract: 158,581. Marks, E. C. R., (Blake, Inc., C. C.). July 30, 1918 Carving.-In a machine for use in the manufacture of shoes and lasts of the type providing automatic relative movement between a work support and an operating tool to transfer the point of operation of said tool around a piece of work mounted on said support, the path of relative movement is determined by a pattern, and automatic mechanism is provided for relatively shifting the tool and work support during said relative movement to cause the tool to deviate from the path determined by the pattern. As shown, an insole 1 secured to a last 2 is trimmed by an oscillating knife 50. The last is mounted on a work support having runners 4 sliding over a table 5. The horizontal movements of the support are determined by a pattern 12, Figs. 1 and 12, having a depending flange engaged between rollers 29, 30, 31, Fig. 5, which keep the edge of the insole adjacent the operating point of the tool. The rollers 30, 31 are mounted on links 39, 40 and guided by pivoted links 43, 44 the links 39, 40 being pivoted to a pivoted arm 41 the free end of which is controlled by a compression spring 47 to press the rollers 30, 31 towards the roller 29. The roller 29 is carried by a pivoted arm 33 and moved to grip the pattern by a toggle 36 having a handle 37. The members 41, 47 form a toggle so that the pattern is held more firmly when the ends are being operated on, the pressure of the rollers decreasing as the toggle approaches a straight line. The pattern has rack teeth meshing with a pinion driven through bevel and worm gearing from an electric motor to traverse the edge of the sole past the tool. To cause the relative path of tool and work to deviate from that determined by the pattern, the table 5 carrying the pattern and work support is shifted toward the tool at a point in the path, and returned at a subsequent point, the object being to cut away the insole from A to B, Fig. 12, to allow space for a toebox. To this end the table 5 is carried by a bracket 8 connected by a link 85, Fig. 8, with an eccentric 81 turned through half a revolution when the tool reaches the parts of the sole determined by the points A and B of the pattern. At these points the depending flange of the pattern is recessed to allow a pin 100. Fig. 5, which is normally pressed downwards by the flange to ascend momentarily. The pin is loosely carried by the lever 33 and is connected by link and lever mechanism with an arm 96. Fig. 8, engaging stops 97. 98 on a ring controlling the position of clutch cylinders 91 between an outer member 88 constantly driven by the motor and inclines on a disc 87'keyed to the eccentric 81. When the pin 100 enters the recess in the pattern, and allows a spring 99 to move the arm 96 and release the stop 97, a spring 93 moves the controlling ring and wedges the cylinders 91. The eccentric is thus clutched to the member 88 and moves it half a revolution, the second stop 98 contacting with the arm 96 to free the cylinders 91. The disc 87 is held in the exact positions desired by a spring- held pawl 113 engaging one of two stops 111, 112 kept in contact therewith by the spring 93. A flywheel 122 geared up to the eccentric ensures its moving the full half-revolution. The knife 50 is adjustably carried by an arm 54, Fig. 2, pivoted at 55 and oscillated by an eccentric on the armature shaft of an electric motor 79. The motor carries a cradle 52 supporting the knife, a spring- pressed roller 63 bearing on the edge of the insole and a, guide 51 engaging between the edge of the insole and the last. The armature shaft is supported on ball bearings so that the cradle may swing freely to maintain the knife substantially normal to the sole at the point of operation. To allow the work to rise and descend under the influence of the guide 51 and roller 63 the work table is supported by a spring 58, Fig. 1, engaging a treadle lever 59 having a link 60 supporting the standard 6 of the table 5, which standard is guided by rollers 61 engaging slots in the bracket 8. The motor traversing the pattern has a controlling treadle 140, Fig. 11, linked to an arm 136 adapted to press the armature away from its magnetic centre and engage a friction clutch 133, 134. When the pedal is released a spring 141 causes a brake 142 to engage the member 134 and stop the pinion gearing with the rack on the pattern. The bearing of this pinion is pivoted and spring- held to allow the pattern to be placed in position even though the teeth do not mesh. When the pattern is removed from the table 5, a cam carried by the arm 40 engages one of the levers from the pin 100 and prevents the pin rising under the influence of the spring 99. A pointer is provided to indicate the position of the bracket 8. The invention may be applied to machines for shaping the bottoms of lasts. Specification 158,774 is referred to.