GB983286A - Improvements in or relating to winding and reeling machines - Google Patents

Abstract

983,286. Feeding strip material. E. MULLER. Feb. 24, 1961 [March 4, 1960], No. 6815/61. Heading B6B. [Also in Division D1] An apparatus for maintaining constant tension in a material to be wound has a guide roller which is mounted on a movable part tending to assume a rest position and which is deflected from this rest position by the tensional force acting on the material, this movable part controlling a brake drum and brake cable thereon such that the effect of the brake decreases to decrease the tension in the material when there is an increase in the deflection of the movable part from its rest position, and such that the brake increases the tension in the material when there is a decrease in this deflection there being a second brake upstream of the guide roller acting directly on the material and applying a preliminary tension thereto. The material may be threads, yarns, wires, film, foil-like strips &c. According to a schematic construction, Fig. 1, a yarn W is passed over a guide roller R before being drawn off in the direction Z. Rotation of the roller R by the yarn W rotates a brake drum T around which a brake cable B 2 extends between a fixed point F and a point O on a pivoted pendulum like member P. The member P carries the brake drum T and the guide roller R. When the tension in the yarn W increases the pendulum is rocked towards the fixed point F and this reduces the braking effect of the cable B 2 and so reduces the tension in the yarn. V is the upstream brake acting directly on the yarn. In a further embodiment, Fig. 6, the yarn 40 is wound round a pulley 39 in a trolley 35 before being drawn away over a guide roller 42. The spindle for the pulley 39 is rigid with a brake drum 41 around which is coiled a brake cable 43 extending between the points 44 and 45. When the tension in the yarn being drawn off the roller 42 increases, the trolley 35 tends to move up a ramp 33 and this reduces the braking effect of the cable 43 and so reduces the tension in the yarn. The tension required can be set by means of a screw 34 for adjusting the inclination of the ramp 33 about the axis of the guide roller 42. A preliminary brake (not shown) acts on the yarn upstream at the drum 41. In a further embodiment, Figs. 8 and 10, Fig. 10 being a rear view of Fig. 8, a brake drum 69 is encircled by a brake cable 70 secured between the fixed part 71 and a part 55 on a pendulum 54 pivoted at 53. The pendulum is biased away from the brake drum 69 by a lever 60 rocking on a displaceable pivot 61, one end of the lever 60 being acted on by a spring 65 and the other end of the lever being coupled to the pendulum 54 at 59. The yarn 57, Fig. 8, passes over a guide roller 56 carried by the pendulum and thence around a roller 68 coupled by a spindle 67 to the brake drum 69. As the tension in the thread increases the pendulum 54 is rocked towards the brake drum 69 and this reduces the braking effect of the cable 70 and so reduces the tension in the yarn. The degree of tension can be set by adjusting the position of the pivot 61. The preliminary braking device is provided at 72.