GB1008291A - Apparatus for winding flexible material - Google Patents

Abstract

1,008,291. Winding up flexible material; tension control. BRITISH INSULATED CALLENDER'S CABLES Ltd. May 22, 1964 [May 24, 1963], No. 20916/63. Headings DID and D1T. An apparatus for controlling the tension in flexible material being wound on to a take-up drum comprises main driving means for positively feeding the material towards the drum at a controlled linear speed or for controlling such feeding and means for rotating the drum comprising a differential gear, one member of which is couples to said main driving means, another member of which is coupled to the drum carrier and the third member of which is coupled to an auxiliary power source which has torque/speed characteristics such that it exerts a torque that is dependent on its speed. In Fig. 2 a pair of flexible members are twisted together to form a strand by passing said members through the flier 26 and then winding them on to a rotating take up drum 20. The flexible members are fed to the flier 26 by capstans 5 and 6 (only 6 is shown in Fig. 2), the speed of the capstans being maintained in a constant relationship with the speed of the flier to determine the length of lay of the two flexible members. The invention relates to means for controlling the tension in the flexible material as it is wound on to the drum 20 and is of the kind that automatically varies the speed of the drum 20 in accordance with the torque applied to the drum by the tension in the material. In Fig. 2 and 3 a main driving motor 29 drives the flier 26 via belt 30, shaft 27, and belt 18. The main motor 29 also drives an upper sun wheel 32 Fig. 3 and a tachogenerator 31 Fig. 2. The lower sun wheel 34 is driven by a torque motor 37 the arrangement being such that the lower sun wheel 34 is driven in opposite direction and at a lower speed than the upper sun wheel 32. The torque motor 37 has a torque/speed characteristic such that it exerts a torque that is inversely proportional to its speed. The cage 38 of the differential gear carrying the plant wheels 39 is geared via a pinion 42 to a splined shaft 45 rotating the drum 20. To traverse the flexible material on to the drum 20 the splined shaft 45 is reciprocated by a reversing motor 50. In the machine described the drum 20 always rotates at a speed less than the speed of the flier 26, the difference in speed being such that the cable is wound on the drum under tension. The desired tension is obtained by adjusting the supply voltage to the torque motor 37. As the number of layers of cable wound on the drum 20 increases, the tension in the cable will tend to decrease but since any decrease in tension in the cable would decrease the load on the torque motor 37 and thus increase its speed, the necessary decrease in speed of the drum 20 to keep the tension substantially constant is automatically effected. Controlling the speed of the capstans 5, 6. The capstans 5, 6 are driven by a motor 9 that also drives a tacho-generator 10. The field current supplied to the motor 9 is proportional to the difference between a proportion of the output of the tacho-generator 31 (reduced by a rheostat 61, Fig. 6, not shown) and the output of the tachogenerator 10. Hence the speed at which the capstans 5 and 6 are driven by the motor 9 is always a constant proportion of the speed at which the flier 26 is driven by the motor 29, the actual proportion (which controls the lay length of the finished cable) being dependent upon the setting of the rheostat 61.