Patent GB-1041400-A (GB)
Title: Improved method and mechanism for the coiling of spools of constant length of thread
IPC: B65H63/08
Filed: 1963-11-29
Abstract: 1,041,400. Winding yarn packages of constant length. FR METTLER'S SOHNE MASCHINENFABRIK. A.G. Nov. 29, 1963 [Nov. 30, 1962], No. 47267/63. Headings D1F and D1J. [Also in Division G1] To wind yarn packages of constant length, the revolutions of a package being wound are used as a means for maintaining the diameter of the yarn package at a diameter predetermined as a function of its number of revolutions. This may be done by exerting pressure on the package, the pressure increasing if the package diameter is too great and decreasing if it is too small. Alternatively the tension in the yarn may be increased if the package diameter is too great and decreased if it is too small. In Fig. 1 the package 4 is in engagement with a grooved yarn traversing drum 2, the package 4 being supported by a frame 14, 15, 16 that can swing upwardly about an axis 30. The spindle of the package 4 carries a worm 24 which, through suitable gearing, rotates a crank 50 about the axis 30 to rock a lever 45 about an axis 41. The oscillations of the lever 45 cause a ratchet 43 thereon to turn a ratchet wheel 42 the rotation of which drives a shaft 37. The shaft 37 has a worm 35 that meshes with a toothed sector 34 rigidly coupled to the frame 14, 15, 16. Thus, as the package 4 rotates the frame 14, 15, 16 swings upwardly at a predetermined rate. If the package diameter tends to exceed its permitted diameter the pressure between the drive drum 2 and the package 4 increases to cause the windings to be wound more tightly and if the package diameter does not increase at the permitted rate the pressure between the drive drum 2 and the package 4 decreases to cause the windings to be wound on lightly. In Fig. 5 (not shown) the frame 14, 15, 16 carrying the package 4 is freely pivoted about the axis 30, the frame being rigid with a depending arm 70. The spindle of the package 4 carries a worm 24 which, through gearing, rotates a screw spindle 61 to displace a nut 62 thereon. The nut 62, Fig. 6 (not shown), in the base of a U-shaped support 63 one leg 64 of which carries a lamp 68 and the other leg 65 of which carries a photoelectric cell 69. The arm 70 extends between the legs 64, 65 and has a slot 71 through which the lamp 68 can shine on the cell 69. The output of the cell 69 is connected through an amplifier with a solenoid coil 73 of a thread brake 74. The brake 74 comprises a pair of discs 77, 78 the first of which is biased against the second by a spring 80. As the package diameter increases the arm 70 and the nut 62 move in unison to the right and sufficient light passes on to the cell 69 to cause the solenoid 73 to counteract the spring 80 to the desired extent. If the package diameter increases beyond its permitted rate the arm 70 moves to the right at a faster rate than the nut 62 to cause a reduction in the light passing on to the cell 69 and so reduce the effect of the solenoid 73. The resulting increase in the tension exerted on the yarn 74 causes the package to be wound tighter. If the package diameter does not increase at its permitted rate the nut 62 moves to the right faster than the arm 70 to cause an increase in the light passing on to the cell 69 to increase the effect of the solenoid 73. The resulting decrease in tension in the yarn 74 causes the package to be wound lighter. In a modified embodiment of that described with reference to Figs. 5 and 6 the nut 62 carries a potentiometer and the arm 70 carries a slider acting on the potentiometer, the potentiometer and slider being suitably connected to the solenoid 73 of the brake 74. In a further embodiment, Fig. 8 (not shown), the package 4 is mounted in a frame 14, 15, 16 that is caused to swing upwardly about the axis 30 at a rate dependent upon the revolutions made by the package. The package shaft carries a plurality of flat mirrors that reflect light rays, according to the speed of the package spindle, on to a photoelectric cell. The impulses produced by the cell are used to raise the frame 14, 15, 16 in a desired manner dependent on the revolutions made by the package. This varies the pressure exerted on the package by a grooved drum 2 and hence the density at which the package is wound.