Patent GB-1018601-A (GB)
Title: Improved strip shear mechanism
Inventor: LAWSON KENNETH THOMAS
IPC: B23D25/06
Filed: 1962-08-22
Abstract: 1,018,601. Shearing. HEAD, WRIGHTSON & CO. Ltd. Nov. 22, 1963 [Aug. 22, 1962], No. 32247/62. Heading B3W. In a pendulum-type flying shear the bottom blade 22 is constrained to follow a circular orbital path and the top blade 10 is constrained to follow an oscillatory path and means are provided for constraining the two blades to take up the same relative position during each cutting operation. A shearing line comprises a constant speed feed and flattening device and a shear which are both driven by a constant speed motor, the drive to the shear being through a continuously variable gear unit. The top blade 10 is mounted on a beam 11 carried by a tube 15 which is pivotally mounted in bearings 16 carried in cross-heads 19 and 20 arranged on a main frame 21. The bottom blade 22 is mounted on a beam 23 which is detachably secured via couplings 27 to blocks slidable in radial slots in flywheels 29 mounted in bearings 30 and 31 in the frame 21, and driven by pinions 33, Fig. 4 (not shown). The beam 23 slides between two spaced arms 36 secured to the beam 11 so that as the flywheels rotate the top blade 10 oscillates over the passline of the strip L. To match the speed of the blades to the speed of the strip the blade mounting blocks can be moved along the flywheel slots by screws 39, Fig. 6 (not shown), engaged in nuts 40 which are mounted in the flywheels and are rotated by shafts 55 and 56 through gears. The shafts 55 and 56 are connected by a layshaft 58 and receive their drive from a motor 41, Fig. 3 (not shown), through a worm 44 and wheel 45 and a sun and planet gear 48-50 and 52-54. Means are also provided to adjust the vertical position of the top beam 11 and the blade 10 to maintain the correct relationship between the blades 10 and 22 according to the length of strip to be cut, and since this adjustment is dependent upon the adjustment of the bottom beam as described above, both adjustments are made simultaneously by the motor 41. For this purpose the motor also drives a gear-box 67 and a shaft 68 which has worms 69 which each drive two screws 72 which raise or lower the cross-heads 19 and 20. The shaft 68 is extended at one end 75 and coupled to the speed control of the continuously variable gear unit and the other end 76 of the shaft is extended and coupled to a mechanism for raising and lowering the feed device, the height of which is adjusted in accordance with the height of the pass line L of the strip, this height varying according to the length of the cut. The machine includes a miss-cut mechanism which enables primary selection from a plurality of sheet-length ranges to be effected. For this purpose the bearings 16 of the tube 15 are mounted in eccentric bores in carriers 17 and 18 and the carriers which are connected by a spindle 83 are driven from a three-speed gear-box 78 through gears 81 and 82. The input to the gear-box 78 is by bevel gears from one of the flywheels 29 and the gear ratios are chosen so that the carriers 17 and 18 can be driven at one half or one third of the speed of the bottom beam 23, so that the top blade 10 is only in position to co-operate with the bottom blade at every second or third cycle of the shear.