Patent GB-1321464-A (GB)
Title: Automatic cutting machine
IPC: B26D1/38
Filed: 1970-09-22
Abstract: 1321464 Cutting apparatus MUTO INDUSTRIAL CO Ltd 22 Sept 1970 [22 Sept 1969 31 Oct 1969] 45169/70 Heading B4B An automatic machine for cutting sheet material e.g. cloth, comprises a cutting table 23 including a material supporting surface formed from a sponge-like material through which a suction can be applied by means 147, 150, Fig. 7, for holding the material on the table, a reciprocable cutting blade 31 mounted on a carriage 27 for movement over the table and adapted to be raised or lowered by means 71, 72, 57, Fig. 2, out of or into engagement with the material, and a mechanism 88, 90, 81 for controlling the angular rotation of the blade. The carriage 27 is slidably mounted on a bar 26, Fig. 1, which is movable over the cutting table by means of belts driven by an electric motor. The cutting blade is reciprocated by means of an electric motor 32 mounted on the carriage, the motor rotating a double-ended crank-shaft 40 by means of a gear 34. One end 45 of the crank-shaft is coupled to one end of a connecting rod 46, the other end of the rod being connected to a sleeve 49 guided in a bearing 59; the sleeve is connected via a spring 67, to a shaft 57 on which the blade 31 is secured. The other end 36 of the crankshaft is coupled to one end of a connecting rod 37, the other end of which being connected to a balance weight 53 reciprocable in a bearing 52. The lifting means is in the form of a piston- and-cylinder device 30, Fig. 2, the piston 72 being connected to an arm 68 which is also rotatably connected to the shaft 57, the arm being adapted to engage a shoulder 70 on the arm. The shaft 57 is angularly rotated by an electric motor 88 via gears 90, 81, the latter motor and the motors for moving the carriage 27 and the bar 26 being under the control of signals fed from a computer. In modifications, (Figs. 3, 4, 5, 6, not shown), the double-ended crankshaft 40 is replaced by two separate shafts rotated, via gears, by the motor 32, one shaft being arranged to reciprocate the sleeve 49 and the other connected to the balance weight. The table 23 is in the form of a box having walls 24, Fig. 7, for containing blocks of sponge-like material 138 separated by strips of impervious soft material 137, the separate blocks of sponge being connected with a suction source 150 via holes 136, chambers 135, pipes 147 and chambers 142. In order to reduce the suction power required, the suction is only applied to the particular block of sponge material through which the blade 31 is travelling (see Fig. 7), this being effected by means of a belt 145 having a port 149 which is aligned with the respective chamber 142, the belt being connected to the drive for the cutter carriage 27. In modifications, the particular chamber 135 to which the suction is applied may be selected by means of solenoid-operated valves actuated by switches (181, 182, Fig. 12, not shown) controlled by the bar 26 or by a rotary valve member (Fig. 9, not shown) driven from the carriage belt drive. In a further modification, Fig. 14, the sponge-like material is replaced by densely packed bristles 180 through which a suction can be drawn via a source 150; a sheet of impervious material 185 may be placed over the cloth 283 in order to increase the suction. In the modification shown in Fig. 15, the material 283 to be cut is held down during cutting by means of rollers 197, 198. The cutting edge of the blade 31 may be of wavy form or provided with cutting teeth and the blade may be circular, triangular or oval in cross-section. Several cutting edges may be formed on a circular cross-sectional blade.