GB942819A - Improvements in or relating to manufacture of articles from strip metal - Google Patents

Abstract

942,819. Feeding webs. HUMPRIS & SONS Ltd. Aug. 3, 1961 [Aug. 26, 1960 No. 29521/60. Heading B6B. [Also in Division B3] An apparatus for feeding strip material comprises means for driving a reel to unwind the material thereon in a direction away from the machine, means for guiding the material under the reel to feed means of a following machine thereby forming a loop in the material on the side of the reel remote from the machine, and control means operated by the loop to control the drive means of the reel and maintain the loop between a minimum and maximum position. A reel 10 is driven by a constant speed motor 14 through an electromagnetic clutch 12 and a gear-box 13 and braked by a brake 15. The strip forms a loop 17 which when it becomes too large cuts a light beam 22 and through a photo-cell and control unit 21 disengages the clutch 12 and if necessary applies the brake 15. The strip then passes under the reel to a pair of feed rolls 16 and measuring rolls 19 associated with a cutting or fabricating machine 20. A safety switch comprising a roller 23 carried on a pivoted arm 24 switches off the machine 20 if the loop becomes too short. Tension in the strip is maintained by pivoted arm 26 which has a roller 25 rotatably mounted thereon. In a modification (Fig. 2, not shown) the clutch is replaced by a variable speed unit which is controlled by three photo-cells. Two of the photocells vary the output speed of the unit so that the loop cuts the light beam to one of the cells, but not to the other, and the third photo-cell reduces the output speed to zero and applies the reel brake when the loop becomes sufficiently large to cut it. A further photo-cell switches off the fabricating machine when the loop becomes so small it no longer cuts the light beam to that cell. Specification 942,820 is referred to.