Apparatus for Opening and Cleaning Cotton Waste

This invention relates to an apparatus for opening and cleaning cotton waste particularly strips, card fly, scutcher waste, comber waste, filter waste and under-card waste. The apparatus comprises a fiber feed arrangement for advancing the fiber material to an opening roll and further has a screen which is situated downstream of the feeding device in the direction of the opening roll as well as a fiber collecting bin. An apparatus of this type is disclosed, for example, in German Published Accepted Application (Auslegeschrift) No. 2,755,380.

It is an object of the invention to provide an improved apparatus of the above-outlined type in which the degree of opening and cleaning is substantially increased.

This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the screen is arranged eccentrically with respect to the beater roll and further there is provided an openable and closable cover which is situated downstream of the screen in the direction of the beater roll. During operation the shroud is periodically opened to allow passage of the cleaned fiber tufts into an outlet.

The invention is based on the principle according to which a dosed quantity of waste is advanced in a narrow beater chamber with the aid of a beater roll over a large-surface screen until a predetermined pre-cleaning is achieved. Additional components such as guide plates, beater strips, work rolls, cutters, strippers or the like can be dispensed with. With the structure according to the invention the fiber tufts are opened and cleaned in a gentle manner. According to the invention, the screen is arranged eccentrically with respect to the beater roll and the space between the beater roll and the housing is very narrow and is so formed that it allows the fiber material to drift in a pulsating manner into and out of the circumscribable circle of the beater roll upon each revolution thereof, while the fiber tufts can leave the chamber only for very short periods. In this manner, during the entire cleaning interval (2 to 5 seconds) the fiber tuft material is imparted a high velocity so that the fiber tufts formed by alternating buildup are advanced over the screen and are freed from dust and cleaned continuously by centrifugal force. Since the screen and the beater roll are the only working components, the high cleaning effect of the apparatus according to the invention can be traced in particular to the advantageous configuration of the beater chamber and screen in conjunction with the intermittent operational mode. A particular advantage of the invention resides in the fact that the waste material is pre-cleaned in such a manner that it may be subsequently cleaned by means of a single beater pass to such an extent that it may be again introduced into the cleaning line without soiling the fresh cotton.

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

FIG. 2 is a side elevational view, on an enlarged scale, of a detail of FIG. 1.

FIG. 3 is a sectional view of a detail of the structure shown in FIG. 1.

Turning to FIG. 1, there is shown a feed chute 1 into which waste material from individual machines of a cleaning line is introduced. At the lower end of the feed chute 1 there are arranged two oppositely rotating feed rolls which draw the material from the feed chute 1 and advance the material to an opening roll (beater roll) 3 arranged downstream of the feed rolls 2. The opening roll 3 which preferably has a diameter of 350-400 mm, rotates with a circumferential speed of approximately 13-15 m/sec. Along the circumference of the opening roll 3 there are arranged a plurality of strip-like supports 3a (FIG. 3) extending parallel to the axis of the opening roll 3. The number of the supports 3a is preferably between 5 and 7. Each support strip 3a is provided with a series of spaced pins 3b of circular cross section, as shown in FIG. 3. The opening roll 3 is closely surrounded by a housing which is formed in part by a screen 4 and a shroud 5. The latter may be rotatable about an axis A extending parallel to the longitudinal axis of the opening roll 3. The screen 4 is arranged eccentrically with respect to the opening roll 3 whereby the distance between the opening roll 3 and bars 4a forming the screen 4 increases as viewed in the direction of rotation of the opening roll 3. The surface of the screen 4 extends approximately 40-50% (that is, approximately 140.degree.-180.degree.) over the circumferential face of the opening roll 3. The screen bars 4a, shown in detail in FIG. 2, are centrally adjustable. Underneath the screen 4 there is provided a waste collecting space 9 which is at atmospheric (neutral) pressure. The shroud 5 is situated downstream of the screen 4 as viewed in the rotational direction of the opening roll 3. It may be opened in the direction of the arrow B by rotating it about the axis A. In the closed position shown in FIG. 1, the shroud 5 is a smooth (not angled) continuation of the screen 4. The height of the fiber column in the feed chute 1 is sensed by a sensor 7 which, for example, may be a photocell. The feed rolls 2 and the shroud 5 are controlled electromechanically by a timing device (not shown). By means of such a control device the collecting space 9 is periodically and automatically emptied.

In the description which follows, the operation of the above-described apparatus will be set forth.

The waste material is advanced by the feed rolls 2 to the opening roll 3 which repeatedly takes the material through the annular space 8 over the inner face of the screen 4. During this operation the shroud 5 is in its closed position as illustrated in FIG. 1. By virtue of centrifugal forces foreign bodies such as fragments or dust fly into the collecting chamber 9 through the intermediate spaces between the bars 4a of the screen 4. After the opening roll has performed, for example, 20 to 30 revolutions, the shroud 5 is automatically opened, whereby the pre-cleaned material is advanced into the feed (outlet) chute 6. From the feed chute 6 the material is transferred to an after-connected cleaning machine such as, for example, a Novacotonia NCA model manufactured by Trutzschler GmbH Monchengladbach, Germany. Although the entire pre-cleaning process which is performed in the chamber 8 is performed intermittently, and likewise, the feed chute 6 is charged intermittently, the charging of the feed chute 1 and the discharging of the feed chute 6 are continuous. The heights of the material column in the feed chutes 1 and 6 are regulated by an otherwise conventional control device having sensors 7 (for the feed chute 1) and 10 (for the feed chute 6). In this manner, the quantities introduced by the feed rolls 2 and the cleaning periods determined by the timing device may be set arbitrarily so that the apparatus can be adapted to different types of fiber material to be opened and pre-cleaned.

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.