Web Guiding Device for a Carding Machine

This invention relates to a web guiding device mounted in a carding machine for withdrawing and gathering a fiber web discharged by a web delivering assembly of a carding machine. The web delivering assembly comprises a roller pair (such as squeezing rollers). The web guiding device comprises a guide element arranged immediately downstream of the roller pair as viewed in the direction of web discharge. The guide element has at least one operationally stationary guide face which traverses the plane of the fiber web and further, the upper longitudinal edge of the guide element extends immediately adjacent and along the upper roller of the roller pair.

In a known arrangement, the lower longitudinal edge of the guide element is arranged immediately adjacent and along the lower roller of the roller pair. Such an arrangement is disadvantageous because particularly in case of heavily soiled cotton, the impurities or waste crushed by the squeezing rollers do not drop downwardly out of the arrangement, but accumulate at the inside of the lower, curved zone of the guide face.

It is an object of the invention to provide an improved web guiding device of the above-outlined type, by means of which an accumulation of waste on the guide face of the guide element is prevented.

This object and others to become apparent as the specification progresses are accomplished by the invention, according to which, briefly stated, the longitudinal lower edge of the guide element is arranged at a sufficient distance from the lower roller of the roller pair of the web delivering assembly for allowing waste to drop out of the guide element.

The guide element according to the invention thus has three zones: an upper curved, closed zone which shields the fiber web from above, thus preventing air streams from entering the guide element from above. Such air streams are particularly adversely affecting the marginal zones of the fiber web. The upper closed zone of the guide element is adjoined by a central zone which, in turn, is followed by a lower, open zone. The latter provides that waste can freely fall downward from the squeezing rollers.

According to a preferred embodiment, the guide face extends from the central zone downwardly in a vertical direction. Such a planar configuration is simple to manufacture. Further, by prolonging the guide face downwardly, additional air streams may be prevented from entering the space between the roller pair and the guide element.

According to another preferred embodiment, the open, lower zone of the guide face has such a downwardly inclined course that the waste may slide downwardly thereon. By inclining the guide face in the direction of the rollers, again, additional air streams may be screened off.

FIG. 1 is a schematic side elevational view of a carding machine incorporating a preferred embodiment of the invention.

FIG. 2 is an enlarged schematic side elevational view of a detail of FIG. 1.

FIGS. 3 and 4 are schematic side elevational views of two further preferred embodiments of the invention.

FIG. 5 is a schematic perspective view of an additional preferred embodiment of the invention.

FIGS. 6a and 6b are schematic perspective and top plan views of still a further preferred embodiment of the invention.

FIG. 6c is a sectional view taken along line A--A of FIG. 6b.

FIG. 6d is a sectional view of a modified part of the embodiment shown in FIGS. 6a-6c.

Turning now to FIG. 1, there is schematically illustrated a carding machine which has a web delivering assembly including two squeezing rollers 1 and 2, downstream of which (as viewed in the direction of web advance) there is arranged a web guiding element 3. The longitudinal upper edge 4 of the guide element 3 is slightly spaced from the upper roller 1 and projects, in an upstream direction, beyond the highest point thereof. The lower longitudinal edge 5 of the guide element is situated at a distance from the surface of the lower roller 2. As shown in FIGS. 1 and 2, the guide face 6 of the guide element 3 extends vertically downwardly, while the upper curved zone of the guide element is adjoined by a planar zone. The guide face 6 is prolonged downwardly, that is, the lower longitudinal edge 5 is situated at a lower level than the lowermost point of the lower roller 2. The distance between the upper longitudinal edge 4 and the surface of the upper roller is, for example approximately 2.5 to 5 mm, while the distance between the planar zone of the guide face 6 and the periphery of the lower roller 2 is approximately 30 to 40 mm.

In the embodiment illustrated in FIG. 3, the guide face 6a of the guide element 3a is inclined downwardly in the direction of the squeezing rollers 1 and 2. Such an arrangement provides that waste material can slide downwardly on the inner face of the guide face 6a.

In the embodiment illustrated in FIG. 4, the upper longitudinal edge 4a of the guide element 3b is situated approximately at the height level of the center point of the surface of the upper roller 1. The vertically oriented planar central zone of the guide face 6b is adjoined by an obliquely oriented planar lower zone 15 which is inclined in the direction of the rollers 1 and 2.

In the embodiment illustrated in FIG. 5, the central zone of the guide element 3c is provided with an opening 7 for delivering the sliver formed from the fiber web. The opening widens in a V shape upwardly and terminates on the one and the other side of the guide element in longitudinal edges 4a' and 4a" respectively. The longitudinal edges 4a' and 4a" extend, similarly to the longitudinal edge 4 in the embodiment discussed in connection with FIGS. 1 and 2, beyond the uppermost point of the top of the upper roller 1. The lower longitudinal edge 5a of the guide element 3c is situated at a distance from the lower roller 2.

Turning now to FIG. 6a, there is shown a further embodiment in a perspective view, wherein the lower longitudinal edges 5b' and 5b" form two acute angles with the longitudinal axes of the squeezing rollers 1 and 2. As seen in FIG. 6b, the fiber web 9 leaves the squeezing roller pair (of which only the upper squeezing roller 1 is shown) and impinges, with its edges 9a, 9b (shown in phantom lines) on the guide face 6c of the guide element 3d and, as a result, it is rolled inwardly and gathered and thereafter leaves the guide element 3d as a sliver 12 through the opening 11. The sliver 12 passes through a trumpet 13 and a calender roller pair (of which only one roller 14 is shown). The guide element 3d is downwardly open, so that waste may fall downwardly from the fiber web 9. The lower longitudinal edges 5b' and 5b" are arranged at such an acute angle with respect to the longitudinal axes of the squeezing rollers 1, 2 that, on the one hand, the edges 9a and 9b of the fiber web 9 impinge on the guide face 6c and are deflected by the latter and, on the other hand, the fiber web 9 is still open, that is, it has a quasi-triangular shape. In its state between the squeezing rollers 1 and 2 and trumpet 13 the fiber web is extremely thin; it is formed of interhooked individual fibers and thus is relatively open so that waste particles and other impurities may readily be released thereby. FIG. 6c shows in cross section the curved guide element 3d which is surrounded by a rectangular supporting housing 8. FIG. 6d shows in cross section a rectangular guide element 3e which may be substituted for the guide element 3d.

It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.