GB1022157A - Device using a shearing element in a fixed position to cut constant lengths from a strip moving past at high speed - Google Patents

Abstract

1,022,157. Shearing. SOC. NOUVELLE SPIDEM and COMPAGNIE GENERALE D'ELECTRONIQUE INDUSTRIELLE LEPAUTE. June 10, 1964 [June 12, 1963], No. 24036/64. Heading B3W. An apparatus for dividing strip one portion of which is driven at a constant speed by means 2, has gripping rollers preceding a shear 4, which is followed by a constant-speed conveyer 6 and is characterized in that the gripping rollers 3 rotate at a varying speed which is always lower than the speed of the conveyer 6 and are progressively decelerated prior to the cutting period to a small constant speed, stopped at the instant of cutting and immediately afterwards returned to their original speed prior to the progressive deceleration. Construction.-Strip from a coil 1 passes through a straightener 2 to feed rolls 3, 3a, through a reciprocating shear 4 to conveyers 6, 6a, 6b for removing the cut pieces of strip. A carriage 55 supports devices 7, 8, 8a, 9, 10 and 10a which detect the approach of the leading end of the strip. In the embodiment described photo-electric cells are used, other means referred to include limit switches, proximity induction devices and low-tension contacts directly bridged by the strip. The carriage 55 is movable to vary the length cut. The feed rolls 3, 3a are connected by gears 16, 16a and are driven through reduction gearing 17 by a D.C. motor 13 fed from a Ward-Leonard set. The motor drives a phonic wheel 18, Fig. 3 (not shown), which feeds signals through a gate 19, which opens when the leading end of the strip reaches the first detector, to a reverse counter 20. At the output from the counter is a converter for transforming the numerical values given by the wheel 18 into voltage signals of a corresponding amplitude. The converter is supplied by a tachometric generator 12a driven by the motor 12. The output from the converter is added to a small regulating voltage adjusted by a potentiometer 22 and constitutes a reference voltage for controlling the speed of the motor 13. When the leading end of a strip to be divided reaches the detector 7 the speed of the rollers 3 or 3a is progressively reduced until, when the leading end is a short distance from the detector 9, the speed is very low and is determined only by the potentiometer setting. When the detector 9 is reached the rollers 3, 3a are stopped and the shear operates.