Patent GB-672811-A (GB)
Title: Copying machine
IPC: B27M3/20
Filed: 1949-11-07
Abstract: 672,811. Copy-turning. INCOMA SOC. PER AZIONI. Nov. 7, 1949 [March 18, 1949], No. 28506/49. Class 83 (iii). A copying-machine comprises a rotary templet 2, means for supporting two workpieces 3, 4 and rotating them in opposite directions in synchronism with the templet, a swinging arm 28 carrying a tracer 25 for following the outline of the templet, two swinging arms 32, 35 carrying tools 30, 33 for operating on the workpieces, means connecting the tracer arm 28 with one of the tool arms and for interconnecting the tool arms whereby oscillations of the tracer arm are transmitted to the tool arms in such a way that the latter oscillate through mutually equal angles and in opposed angular directions. As shown in Fig. 1, the templet and workpieces, such as shoe lasts, are each carried between a headstock and tailstock, of which the shafts 7, 13, 14 are driven. The swinging arms 28, 32, 35 are pivoted at 29, 31, 34 in a frame 27 which is movable on guides 74, 75 on the bedplate 1 and has front and rear covers 76, 77. A link 38 connects the arms 28, 32, and the arm 35 is moved synchronously with the arm 32, but in opposite angular direction, by meshing gears or segments 47, 48, respectively connected by links 44, 51 to the arms ; in a modification, the links 44, 51 are connected to a carriage 54, Fig. 7, movable in a guide 53. The tracer 25 may be a roller rotatable on the arm 28, and the tools 30, 33 may be milling cutters. The tools 30, 33 may be driven by electric motors 69 which are disposed on the arms 32, 35 either coaxial with the tools or the pivots 31, 34, or they may be mounted on the frame coaxial with these pivots; belt or other gearing is provided between the motors and tools. The shaft 7 of the templet 2 is rotated through chain and sprocket mechanism 88, 90, Fig. 1, clutch 82, 84, and worm gearing 80, 81 from an electric motor 79, and the workpieces 3, 4 are driven from the shaft 7 through bevel &c. gearing. The frame 27 is fed by a screw-threaded spindle 93 which is driven through chain gearing 90 ... 92 from the clutch. When the clutch is uncoupled from this drive, it provides a drive through gearing 97 ... 99 for withdrawing the frame 27 with a quick return stroke. Alternatively, a hydraulic motor may rotate the templet and workpieces. A spring 40 or hydraulic, pneumatic or electromagnetic means urges the tracer 25 into contact with the templet, and a hand-operated lever 78 or a hydraulic or electromagnetic control may be provided for lifting the tracer and tools. The links 38, 44, 51 may be formed in screwthreaded sections connected by nuts 56 to permit adjustment of length, or nuts on the screw-threaded ends of the links may serve the same purpose. Means may be provided to prevent back-lash in the drive of the workpieces and oscillation of the swinging arms. In a modification the templet and workpieces may be carried on the movable frame 27 and the arms 28, 32, 35 then perform only an oscillatory movement. In a further modification for making disc cams, the frame 27 carrying the tracer and tools is fixed, and there is no relative longitudinal displacement between such members and the templet and workpieces.