GB1136841A - Improvements in or relating to devices for feeding wires tapes or the like - Google Patents

Abstract

1,136,841. Automatic tension control. S. DAVALL & SONS Ltd. Feb. 25, 1965 [Nov.25, 1963], No.46516/63. Heading G3R. In a system for controlling the feed of elongate material from a reel, means for taking up slack and thereby applying tension to the material progressively controls the speed of drive to the reel and also initiates braking of the reel if the amount of slack becomes excessive. In a magnetic wire recorder, Fig.2, the wire 41 passes over pulleys 51-64 between reels 42, 43 on which the wire is wound. Recording and erasing heads (not shown) are suitably positioned and the wire is moved by driving a capstan 56 and reels 42, 43. Movements of spring-loaded levers 74, 75, which apply tension to the wire by pressure on pulleys 55, 59, respectively control the speeds at which reels 42, 43 are driven so that loop size and hence wire tension is maintained constant on each side of capstan 56. Lead screws 69, 71 respectively driven with reels 42, 43 continuously, move pulleys 51, 64 across the reels to facilitate even distribution. If loop size varies unduly, movement of lever 74 or 75 operates a cam 78 or 79 sufficiently to move a pawl 83 or 84 into engagement with a ratchet wheel 87 or 91 so that one or other of the reels is braked to restore loop size according to the direction of movement and according to whether the loop is too large or too small.