Patent GB-893594-A (GB)
Title: Improvements in or relating to methods of and to apparatus for use in concatenating fibrous materials to form a spun yarn or strand
IPC: D01H4/00
Filed: 1960-02-29
Abstract: 893,594. Spinning yarns; rollers and stopmotions in spinning, &c. machines; twist tubes &c. KEELER, L. M. Feb. 29, 1960, No. 7014/60. Classes 120(2) and 120(3) Yarn is spun by delivering the forward end of a strand of untwisted, parallel, staple fibres into a gaseous, e.g. air, current which detaches and entrains individual fibres in a path perpendicular to the axis of revolution of a rotor, changing the direction of the current as it approaches the rotor so that it moves thereafter longitudinally of the axis whereby the advancing ends of fibres are constrained to move in paths parallel to the axis, whilst trailing ends of fibres are rotated by the rotor about the axis while radially spaced therefrom so that successive fibres are intertwisted. As shown in Fig. 1, a carded sliver S is drafted by back rolls D, aprons A, A<SP>1</SP>, and front rolls T (which is helically ribbed and the action of which is intermittent and incremental) and B (which may be rubber-covered) and delivered by presser roll Q coacting with roll B to a fibre inlet tube 10 through which fibres pass towards a rotor or spinning head 17 attached to the shaft of electric motor M. The rotor comprises head portions connected by a concave barrel 18 which has a central bore 21 communicating with apertures 19 and 20 and accommodating the end of a stationary, perforated tube 22 which leads to a yarn delivery port 25. The air pressure within an upper chamber formed in casing 11 by a system 23 is maintained sub-atmospheric by a pump (not shown) to which a pipe 27 leads, thus establishing a current of air through tube 10, in a chamber 16, through the rotor 17 and tube 22. By the time each trailing end of fibre is released from the nip of rolls Q, B, its forward end is in contact with barrel 18 and the air current will carry it into aperture 19 or 20 and the trailing end is then whipped outwardly contacting the inner surface of casing 11. A probe is inserted through port 25 until it is within bore 21 and the free end of the fibre becomes twisted thereon: the probe is slowly withdrawn, successive fibres becoming twisted on to preceding fibres and the twisted assembly is led to the nip of rolls 28, 29 whereby yarn Y is continuously withdrawn. A modified rotor, Figs. 4 and 5, comprises a single aperture 19a and is used in conjunction with a shortened tube 22a. In another modification, Figs. 6 and 7, adapted for spinning short staple, viz. 0À875 inches- 1À25 inches length, fibre, rotor 17b is a disc mounting bent pins 30, 31, 32, on one of which the leading edges of successive fibres are caught and the trailing ends whirled therearound. In the apparatus shown in Fig. 8, a tubular shaft 34 of motor M provides passage for an air current between exhausted chamber 16x and lower chamber 26m and carries a rotor 17x which has a concave barrel devoid of any opening and an open lower end comprising a fibre-engaging hook 37 at one side of a recess terminating in an eye through which pass fibres forming into a yarn and into which a tapered pin 39 adjustably projects. The yarn Y, in its passage from delivery port 25x to traverse drum 41 winding up a package 42, supports a pivoted feeler arm 40. If the yarn breaks, arm 40 falls to cause an arm 44 to move an actuating pin 45 of a microswitch 46 and thereby energize a solenoid 47 which moves its core 48x to pivot an arm 49a against the restraint of a spring 52 to turn a value 48 until its port 50 registers with a nozzle 51. An air current flows through nozzle 51, at a faster rate than air flows through tube 10x, towards and through an exhausted casing 49, so that fibre will cease to be drawn into the rotor and jamming of the apparatus by fibre accumulation is avoided. When the spinning operation is restarted by use of a probe, the arm 40 is restored to the position shown. The modified rotor 17m of Fig. 11 is generally cylindrical with a central, downwardlyflared bore: air currents whirling around a tapered pin 39m and then moving upwardly in passage 34 cause incoming fibres to wrap loosely around and slide along the pin until engaged and rotated by tufts, as at 53, of bristles on the rotor. Multiple assemblies of the spinning apparatus may be mounted on a spinning frame.