Process and apparatus for removing foreign bodies from textile fibres

摘要

627,044. Removing foreign bodies from fibrous webs. HOFFMAN, M. T. June 22, 1945, No. 16031. Convention date, May 11, 1944. [Classes 120 (i) and 120 (iii)] Foreign matter is removed from wool and other textile fibres by (1) subjecting. a thin web of the fibres to the pulverising action of crushing rolls sufficient to pulverise a part of the foreign matter, (2) subjecting the fibres to a dusting or similar machine or to air blast, so as to rearrange the lie of the individual fibres with respect to each other, and (3) further subjecting the web of fibres to the pressure of additional crushing rolls adapted to pulverise substantially all of the remaining part of the foreign matter. Preferably, the fibres are carded before the first passage through crushing rolls and both before and after the second crushing. In one modification, material is passed through a part 1 of a carding set; Fig. 1, and the carded web produced is subjected to the action of crushing rolls, 4, 5, which may be of the kind described in Specification 444,043. From the rolls 4, 5 the web is carried forward to a duster 10 or similar machine for removing the crushed foreign matter by air currents and centrifugal force. The fibres are further carded in a machine 13, crushed between rolls 19 and passed forward to a finisher card, or to a duster or similar machine. In another modification, the crushing rolls 4, 5 are followed by two series of fluted crushing rolls and dusters. The rolls 4, 5 may be replaced by an arrangement comprising, one, preferably hollow, rod 33, Fig. 4, supported by two rolls 36, 37, against which the roll 33 may be pressed by air, water, oil or other fluid pressure. Rolls 33, 36, 37 may be heated by infra-red, or other means, particularly when paint and tar are present in the fibrous web. In order to effect agitation of the fibres between rolls 36, 37, a wire-clothed roll 39 and/or a series of nozzles 38 directing blasts of compressed air against the fibres may be arranged. Static electricity may be employed to agitate the fibres instead of or in addition to the elements 38, 39. On leaving the nip of the rolls 33, 37, the material may be sucked into the intake flue 40 of a duster. The surfaces of one or more of the rolls 33, 36, 37 may be roughened, fluted or knurled, or the top roll may rotate at a different speed to the lower rolls, or the top roll may be reciprocated axially with respect to the other rolls, to increase the pulverising action. The rolls may be long enough to receive webs from two or more carding machines side by side. The carding machines may have swifts of larger diameter with more workers and strippers than usual to permit of speedier carding and higher productions. In a further modification, the series of fluted rollers may have upper and lower rolls urged together by spring or hydraulic means and air jets or axial reciprocation may be arranged. An arrangement for treating webs from several carding machines is shown in Fig. 9 in which webs pass between nips of two rolls of a stack 86, from which they are sucked into the intake slots 94 of a suction conduit 95 conveying the material to a duster or similar machine, after which it is given a second crushing so as to supply clean stock to a plurality of sets of cards. In another arrangement, several carding parts may be followed by individual crush rolls, from which material is conveyed by suction pipes or otherwise to a common ceiling condenser which removes part of the dust and deposits the material on the feed lattice of a series of fluted crush rolls from which it passes to one or more dusters and a bin, to be distributed by gravity chutes, or otherwise, to several carding parts followed by individual crush rolls delivering to a common ceiling condenser.