Patent GB-1228312-A (GB)
IPC: B65H59/40
Filed: 1969-02-13
Abstract: 1,228,312. Creels; tension control; stopmotion. LEESONA CORP. 13 Feb., 1969 [15 March, 1968], No. 7804/69. Headings DID and D1J. Tension control means for wire from a supply spool includes means that is rotated by the wire as it is pulled from the spool, said rotatable means being coupled to an electric motor so as to rotate it counter to its normal direction of rotation and so impart a drag force to the wire, and electrical control means for the motor to permit changing of the wire tension while the wire is in motion. The apparatus includes means for disconnecting the source of electrical power to said motor upon interruption of the wire from the supply spool. In Fig. 3 the rotatable means in a flier 36 rigid with a spindle 78, the lower end of the spindle carrying the rotor 70 of the aforesaid motor. In Fig. 7 the rotatable means is a pair of discs 160, 164 on inclined axes so that the discs pinch the wire therebetween, one of the discs being coupled to the rotor of the aforesaid motor. The disc 164 has pins around its periphery that are directed towards and are engageable with recesses in the disc 160, the wire 32' resting on these pins. In Fig. 9 one of the discs 172 has a resilient groove 174 in its periphery, the wire 32" running in this groove and being gripped by said groove by the other disc 176. Fig. 1 (not shown) shows a multiple coil winding machine incorporating a plurality of supply reels, each supply reel having an individual braking motor. Fig. 5 (not shown) shows how all the motors are jointly controlled by a single auto-transformer (125) to vary their drag force jointly, and how each motor is, additionally individually adjustable by resistance controls (132). In the event of wire breakage the dancer pulley 48', Fig. 7, will spring up and allow leaf spring 46' to close a switch carried by a bracket 44' to shut off the coil winding mechanism and also de-energise the tension motor 64' controlling the broken wire. Due to mechanical lag in switch operation, the motor 64' will begin rotating in its forward direction and will coast to a stop thus causing the wire 32', in the embodiment in Fig. 3, to be immediately and automatically rewound upon the supply spool. The leaf spring 46' is also coupled to the bracket 44' via a dash pot 50'. The dash pot 50' may be a transparent cylinder having graduations thereon and includes a check valve Fig. 4 (not shown) for damping flutter of the piston coupled-to the leaf spring 46', the piston being visible in the cylinder and its position relative to said graduations being an indication of the tension in the wire. There may be means associated with the leaf spring 46' to provide adjustment of the electrical control means. In Fig. 6 (not shown) such means includes a photo-electric feed back device. It includes a light source (154), a photocell (156) and a first polarized sheet (152) all fixedly mounted on the bracket (44) with the sheet (152) between the light-source and the photocell; and a second polarized sheet (142) mounted for relative rotation in a plane parallel to said first sheet (152) and also located between the light source and the photo cell, the second sheet (142) being movable in response to movement of the leaf spring 46'. The output from the photocell may include a tension readout monitor.