There has long been a need of rapidly removing dust, husks and neps from the cotton coming to the cylinder teeth of a carding machine, so that these contaminants do not disturb the carding process itself and do not wear the teeth on the cylinder or those on the flats, this need also extending to the prevention of the spread of these contaminants into the carding room.

The present invention relates to an arrangement which will satisfy all these needs. In accordance with the invention, the arrangement has been given the embodiment and characterizing features dis¬ closed in the appended claims.

The invention will now be described in detail while referring to the accompanying drawing on which Figure 1 is a cross-section illustrating a flat in a .carding machine, provided ivith an arrangement in accordance with the inven¬ tion, and Figure 2 illustrates an end portion of the arrangement on the flat, as seen in plan towards the cylin¬ der of said machine. In the continued description, orientation is in res¬ pect of the centre of the carding cylinder, and thus "inward" is radially towards the cylinder, "outward" the converse, "forward" in the direction of travel of the ^flats -

•• A-flats-fitting 2,3 ,is adapted in such a waythat it can be _/ attached to a flat for instance by glueing. This fitting: is- in two parts for each flat, the backward par ' 2 being conventionally provided with teeth 16. The forwar 5 face 8 of this part slopes forwards-outwards. The forward part 3 is formed as. a plate with its backward portion having a knife edge 17 at a distance from the forward fac 8 of the part 2, ^' thus forming a slot or gap 5 between the At its forward edge the plate 3 is formed with a bevelled portion 11 adapted for abutting against the inward back edge of the part 2 on the preceding flat.

The plate 3 is provided with outwardly directed spac protuberances 9, arranged to be glued by their flat outwa sides onto the inward side 7 of the flat slat 1. The pro-- tuberances 9 flare forwards from their backward edges 13, which are rounded, and have flat forward faces situated i the same plane as h ^~ forward side of the flat slat 1. A filter 10 is gluei to the forward faces of the protuberan ces 9 and slat 1. The areas between the protuberances 9 are formed as extensions 6 of the gap 5. The backward por tion of the outward side of the plate 3 is provided with rounded peaks 12, of which the ones situated nearest the protuberances- 9 are arranged to converge towards the fil¬ ter 10. The filter 10 can suitably be an extremely fine mesh net, a strip of fibre felt or a strip of foamed plas¬ tics with open pores.

The 1 arrangement functions in the following way _*

Since the cylinder rotates with comparatively large peripheral speed, the teeth of the ^' cylinder fittings wil entrain the air situated between them so that it is given a tangential movement forwards-outwards. When ^" this air :.. meets the front edge 17 of the slot 5, which is travelling in the same direction at a substantially less rate, it . will be forced into the slot 5 where it is caused by the ' peaks 12 to move in a substantially laminar mode and out through the filter 10, leaving behind husks, neps and dust in the extension 6, while air departs through the gap 18 between the fitting 3 and a preceding fitting 2. The por-

tion 11 prevents dust-contaminated air departing through the gap 18 out into the carding room where it could give rise to hygienic problems.

When the flat slat 1 comes to the forward turning point of the slat web, the openings of the gaps 5 are connected to a source of heavy vacuum (riot shown) which sucks the filter 10 clean so that the arrangement is ready to function once again when it comes to the rear turning point of the slat web.