Patent GB-745948-A (GB)
Title: A method of and apparatus for producing coils from thermoplastic filament or strip stock
Inventor: STEGMANN ERNST
IPC: B42B5/12
Filed: 1953-09-07
Abstract: 745,948. Moulding coils from thermoplastic strip material. STORENUND MASCHINENFABRIK E. SCHENKER AKT.- GES. Sept. 7, 1953, No. 24694/53. Class 87 (2). Apparatus for making coils of thermoplastic filament, thin rod and strip stock material comprise transport rollers for moving the stock, coiling tools controlling the diameter of the coils and the pitch of the helical turns and two nozzles adjacent the tools producing a stream of air having hot and cold zones, whereby the stock is heated while being fed to the coiling tools and, when coiled, is cooled. The thermoplastic strip is stored on a roll 11, from which it is drawn off by being passed between a pair of rotating grooved rollers 46, the grooves being of different sizes to suit different filament diameters. The shaft 28 of the lower roller 46 is driven through clutch members 26, 30 from a shaft 24 which is belt-driven from a motor 13. The shaft of the upper roller is gear-driven from the shaft 28 and it is pressed downwards by a spring 41 so that the strip is gripped as it passes through the grooves formed between the rollers 46. Between the reel 11 and the rollers 46 the strip passes through two series of three rollers 128 to straighten it. The strip is urged by the rollers 46 to a roller 57, where it is bent downwards, and then runs up on to a second roller 58 which performs the corresponding turn and at the same time imparts thereto the required pitch. The roller 57, which is grooved to act as a forming tool, is carried on a mount 53 which is movable in a segment 50 by a threaded spindle 54. The roller 58 is carried on a mount 59 which is movable in a block 61 so mounted in the segment 50 that it can be swung about an axle 63, by a screw 64, to control the pitch of the coil turns. After being coiled the strip moves through an eyelet 93, Fig. 5, in a plate 92 and thence to a finger 66 which corrects the pitch of the turns as required. The plate 92 is held at right angles to the front of the machine and is exchangeable to suit the diameter of the strip being coiled. The finger 66 is adjustable by being held at the end of a pin 68 which is movable axially and rotatably in the segment 50. When the coil has reached the desired length the rotation of the shaft 28 is stopped by the action of a cam 116 on the face of a disc 109, Fig. 4, chain-driven from the shaff 24 through a variable gear unit 106, which operates a lever 117 which in turn operates, through an adjustable stop screw 119, Fig. 2, swing arms 121 to disengage the clutch 26, 30. The disc 109 continues to rotate until a cam 112 on its periphery causes an arm 111 to swing and turn an eccentric 96 which moves upwards a carriage 94 which carries a cutting tool 98 which coacts with the plate 92 to form a pair of scissors and sever the coil. As the disc 109 continues to rotate the parts operated by the cams 116, 112 return to their original positions and the forming of a fresh coil commences. The means for heating the strip before the coiling and for cooling it afterwards are provided by a pintle 70, Fig. 5, which projects inwards from the wall of the housing and may be adjusted vertically, by moving its carriage 71, so that it projects into the produced coil. The pintle comprises concentric tubes'74, 75, the inner one, 75, communicating with a cross bar 78 in a cap closing the end of the tubes to form a nozzle. A bore 81 communicating from the outer tube forms a second nozzle. Warm air under pressure is led through a pipe 88 to the outer tube 74 and ejected through the nozzle 81; cooling is effected by sucking air into the nozzle 78 and through the inner tube 75 and a suction pipe 84. The belt pulley 21 on the shaft of the motor 13 is variable in diameter to give various speeds for driving the machines, the flanges of the pulley being spring- pressed together and the adjustment being acquired by moving the motor mounting along bars 16 by the action of a threaded spindle rotated by a hand-wheel 19. In a modification the machine may comprise two coiling tools only, one controlling the diameter of the coils and the other their pitch. Appropriate clamping means, e.g. screws, are provided for clamping the adjustable components in their required positions.