Patent GB-688537-A (GB)
Title: Improvements relating to the spinning of artificial filaments
IPC: D01D5/00
Filed: 1949-07-13
Abstract: <PICT:0688537/IV (a)/1> <PICT:0688537/IV (a)/2> <PICT:0688537/IV (a)/3> <PICT:0688537/IV (a)/4> <PICT:0688537/IV (a)/5> Apparatus for spinning artificial filaments comprises a spinning jet, means for forcing a filament - forming material under pressure through the jet into a setting medium in the apparatus, an annular member surrounding the jet face and leaving an opening through which the filament-forming material can pass into the setting medium, and a jet-engaging member movable relatively to the jet to close the opening and to seal the face of the jet from the setting medium, said jet-engaging member being movably mounted in the apparatus so as to be positively guided into its closing or jet-protecting position.  As shown, the jet protector mechanism is mounted on the wall 4 of the spinning metier on a level with the jet 3 and includes bearings 7, 8 supported in a framework 9 (Fig. 2).  An actuating shaft 11 slidably supported in the bearings extends through a hole 12 in the wall 4 and also through a hole in the block 14 to which it is adjustably fixed by means of a set-screw.  The shaft is encircled by a spring 17 held in compression between the block 14 and a washer 18 bearing on the framework.  The block 14 is also fastened to the shaft 21 of an air cylinder 22 (Fig. 4).  The introduction of air into the cylinder 22 forces the block and shaft against the spring 17 to hold the jet protector in the inoperative position (shown in dotted lines in Fig. 2).  The shaft 11 carries a yoke 24 carrying in its turn a shaft passing through a slot in a lever arm 31 which rotates freely on the shaft 33 supported by bearings on the wall 4.  On the free end of the lever arm 31 is mounted a cup 39 having its edge 41 at an angle to the horizontal plane for engagement with the edge 43 of a complementary cup 42 on the spinning unit. These cups are adjusted so that together with a gasket 44 they seal the jet from the setting medium.  A wiper shaft 46 passes through a central aperture in the cup 39 and is made liquid-tight by a gasket 47 held in position by a liquid-distributing plate 48. A pin 49 extending from the upper end of shaft 46 engages one of four apertures 51 in a wiper plate 52 which carries four sponge-rubber wipers 53.  The plate is furnished with a depending split shaft 56 which engages with a hole in the upper end of shaft 46.  Liquid is introduced into the cup 39 by a hose coupling 61 and passes along a passage-way opening into a channel 63, from which it may pass through apertures 64 in the liquid distributing plate 48, apertures 66 in the wiper plate, over the jet 3 and the sponge-rubber wipers 53 to the passage-way 67 in the outer circumference of the plate 48.  From there it passes to the circumferential channel 68 and out by the hose coupling 72. Flexible hoses 73 and 74 are attached to the couplings 61 and 72. To the wiper shaft is attached a ratchet-wheel 77 surrounded by a shield 80.  The ratchet-wheel is driven by a U-shaped member 81. A flat spiral spring 88 fastened to the cup and to the member 81 is so loaded as to urge the ratchet driving member in Fig. 2 in a clockwise direction, this rotation being limited by a stop 91. On the ratchet driving member is a pawl 93 with a catch 94 formed at one end, and mounted on the cup 39 are a pawl 96 which engages the ratchet teeth 78 and a spring catch 97 positioned to engage the catch 94.  A bar 98 fixed to the cup 42 carries a bolt 101 so positioned as to pass through the shield 80 and to strike the spring catch 97.  When the lever arm and cup 39 are moved into the position shown in dotted lines in Fig. 2, the ratchet driving member is rotated against the spring 88 and the spring catch 97 engages the catch 94 thus locking the ratchet driving member 81. Pawl 93 moves to the next ratchet tooth, pawl 96 preventing counter-rotation.  When the cup is returned to its sealing position, the ratchet driving member 81 is held stationary until the catch 97 is released by striking the bolt 101, and the torsion in the spring rotates the ratchet driving member in the opposite direction carrying with it the pawl 93, ratchet-wheel 77 and wiper plate 52, this last being turned so that a fresh surface of sponge rubber is presented for contact with the jet 3.  On starting the spinning pump motor 106 (Fig. 5) and closing the normally open push-button switch 111, current flows through the holding coil 112 which holds switch 114 closed, and the solenoid coil 113 which draws a valve-operating bar 116 to the left, rotating the air valve 117 and the liquid valve 118 to the spinning position (solid lines).  Compressed air is thus admitted to the air cylinder 22 and the flow of liquid to the cup 39 is prevented.  When the power to the motor fails, the solenoid coil ceases to operate and the bar moves the valves 117, 118 to the position shown in dotted lines, shutting off the flow of compressed air and thus moving the jet-protector into the protecting position and allowing liquid to flow to the cup from the tank 122.  Current through the solenoid may be interrupted independently of the motor by the provision of a normally closed push-button switch 124.  An additional switch operated by pressure in the supply line of the filament-forming solution may also be provided.  In the spinning of cellulose acetate or other acetone-soluble ester of cellulose, the liquid passed through the cup 39 may be acetone, which may be recovered and passed back to tank 122.  Other solvents may be employed.  The apparatus may be used in dry-, wet- or melt-spinning processes.