GB696130A - Improvements in wire drawing machines - Google Patents

Abstract

696,130. Drawing wire. NORTON & CO., Ltd., Sir J. F., and NORTON, W. J. June 7, 1951 [June 14, 1950], No. 14840/50. Drawings to Specification. Class 83 (iv). [Also in Group XXXVII] A wire drawing machine having a number of blocks driven through magnetic clutches has means which, upon the pressing of the " Start " button or its equivalent to set the machine in operation, causes the clutches to be saturated to a value in excess of that required for normal running, such excess saturation being maintained for a short period of time during which the initial inertia and resistance to drawing through the dies is overcome. The electrical system is such that on starting up, the clutches are fully energized, and after a predetermined time lag of up to two seconds, a contactor with a mechanical timing device, or an electronic device, operates to insert rheostats in the clutch circuits to reduce excitation of the clutches. To stop the machine, the driving-motor or motors of the commutator type is or are retarded at a controlled rate, by means of a notor. driven induction regulator, until the torque of the clutches is insufficient to maintain the drawing action, whereupon the clutches are deenergized. With a fixed speed motor or motors the clutches are de-energized at a con. trolled rate until the blocks cease to draw. Limit switches in the aforesaid induction regulator ensure that when the driving motor or motors stop the regulator returns to a position between the limits to which said switches are set, such as to give an initial speed suitable for the particular wire being drawn. Upper and lower speed limit switches stop the pilot motor which operates the induction regulator when the latter reaches either of its limiting positions.