Abstract:
A combination of a sliver intake assembly for guiding and introducing simultaneously a plurality of slivers into a drawing frame and a suction assembly for removing waste, such as dust or fiber fly. The combination includes an emplacement situated below the sliver intake assembly for accommodating a plurality of coiler cans from which slivers are withdrawn by the sliver intake assembly. The suction assembly has a suction duct which extends along the sliver intake assembly in a region thereof for drawing waste thereinto by vacuum.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the priority of German Application No. 195 18 302.9 filed May 18, 1995, which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     This invention relates to an apparatus for removing dust, fiber fly or the like by vacuum from the region of a sliver intake assembly which is situated at the input side of a drawing frame and which includes sliver guiding elements for the slivers withdrawn from coiler cans situated at the sliver intake assembly. The apparatus has air guiding means and a suction device for withdrawing the waste. 
     German Offenlegungsschrift (application published without examination) No. 29 07 747 discloses an apparatus arranged at a feed table of a drawing frame for pneumatic cleaning. The feed table has a plurality of intake locations, each associated with a roll pair defining a clamping gap (nip) for withdrawing sliver from a respective sliver storing device such as a coiler can and further, with each roll pair sliver guiding elements are associated. At least the sliver guiding elements are associated with an air guiding device connected with a vacuum source. Stated differently, an individual suction arrangement is provided for each sliver guiding device associated with the respective roll pairs. It is a disadvantage of this conventional arrangement that dust, fiber fly and the like present externally of the roll pairs and the sliver guiding elements cannot be trapped and drawn away. The flow conditions are only locally defined. Further, the provision of a plurality of individual suction devices involves a substantial technical and constructional outlay. 
     SUMMARY OF THE INVENTION 
     It is an object of the invention to provide an improved apparatus of the above-outlined type from which the discussed disadvantages are eliminated and which, in particular, makes possible an improved removal by suction of dust, fiber fly and the like at the sliver intake assembly of the drawing frame in a structurally simple manner. 
     This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, a combination of a sliver intake assembly for guiding and introducing simultaneously a plurality of slivers into a drawing frame and a suction assembly for removing waste includes an emplacement situated below the sliver intake assembly for accommodating a plurality of coiler cans from which slivers are withdrawn by the sliver intake assembly. The suction assembly has a suction duct which extends along the sliver intake assembly in a region thereof for drawing waste thereinto by vacuum. 
     By virtue of the fact that according to the invention a single suction device with a throughgoing air flow is provided for the several sliver intake locations of the sliver intake assembly forming part of a drawing frame, a plurality of individual suction devices and thus a plurality of air guiding elements associated therewith leading to the plurality of suction devices are avoided, whereby the apparatus is structurally significantly simplified. A single, common suction assembly makes possible a suction removal from the spatial environment of the sliver intake assembly of the drawing frame, as a result of which dust, fiber fly and the like is drawn away by suction even externally of the roll pairs and the sliver guiding elements, for example, from the region of the coiler can tops as the sliver is drawn out therefrom. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1a is a schematic side elevational view of a preferred embodiment of the invention. 
     FIG. 1b is top plan view of the construction shown in FIG. 1a. 
     FIG. 2 is an end elevational view of a variant of the construction shown in FIG. 1a. 
     FIG. 3 is a perspective view of a detail of the structure shown in FIG. 1a. 
     FIG. 4 is a perspective view of a detail of the construction shown in FIG. 1a. 
     FIG. 5 is a perspective view of another preferred embodiment of the invention. 
     FIG. 6 is a schematic end elevational view of yet another preferred embodiment of the invention. 
     FIG. 7 is schematic end elevational view, partially in section, of a variant shown in FIG. 2. 
     FIG. 8a is a perspective view of yet another preferred embodiment of the invention shown in a laterally closed position. 
     FIG. 8b is an illustration similar to FIG. 8a, showing the structure in an open lateral position. 
     FIG. 9 is a perspective view of still another preferred embodiment of the invention. 
     FIG. 10 is a block diagram for the control of the structure according to the invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Turning to FIG. 1a, a plurality of circular coiler cans 1a, 1b and 1c are situated on an emplacement 2a underneath an intake table 2 of a sliver intake assembly for simultaneously supplying a plurality of slivers 3a, 3b and 3c to a drawing frame 6 which may be, for example, a model HS machine, manufactured by Trutzschler GmbH &amp; Co. KG, Monchengladbach, Germany. The intake table 2 of the sliver intake assembly extends over the coiler cans 1a, 1b and 1c and carries a separate roll pair 4a, 5a; 4b, 5b and 4c, 5c for each respective coiler can 1a, 1b and 1c. The sliver extending from the coiler cans passes through the respective roll pair and is introduced therefrom, generally in a side-by-side relationship, into the drawing frame 6 for stretching and combining. At the output end of the drawing frame 6 the outputted sliver is, in a manner not shown, deposited in coils into a coiler can by a rotary coiler head. In the region of each lower roll 5a, 5b and 5c of the respective roll pair, guide elements 9a having upwardly open guide grooves are arranged for guiding the slivers 3a14 3c as illustrated in FIG. 4. There are further provided annular guide elements 10 through which the sliver passes as it rises from the coiler can underneath, immediately before being introduced into the respective roll pair. 
     A suction assembly generally designated at SA which extends over the sliver intake assembly has a duct 7 coupled to a vacuum source 9 for the suction removal of dust, fiber fly and the like as well as a hood generally designated at 8, having lateral hood elements 8a and 8b which may have transparent portions for visually observing the inner space defined by the hood 8. The duct 7 extends parallel to the intake table 2 and above the coiler cans 1a-1c, and the hood elements 8a, 8b cover the sliver intake device, the coiler cans 1a-1c, the roll pairs 4a, 5a, 4b, 5b and 4c, 5c as well as the slivers 3a, 3b and 3c from above and from the side. The arrow A designates the advancing direction of the slivers 3a-3c at the level of the intake table 2, whereas the arrow B which is parallel to arrow A, designates the flow direction of the vacuum-generated air stream in the hood 7. The hood elements 8a and 8b, as shown in FIG. 1, are hinged to the duct 7 for pivotal motion in a vertical plane and are illustrated in their downwardly pivoted closed position in FIG. 1 to thus form an air guiding arrangement. Also, the duct 7, in its closed position, prevents an accidental or undesired access. When deliberate access is to be gained to the sliver intake assembly, for example, for the purpose of replacing the coiler cans 1a, 1b and/or 1c, the hood elements 8a and 8b are pivoted upwardly into their open position as shown, for example, in FIG. 8b and in phantom lines in FIG. 5. It is noted that in the construction according to FIG. 5 additional end panels 8c, 8d, 8e and 8f are provided for closing the inner space of the hood from the front and the rear as well, whereby the hood defines an inner space from four vertical sides. 
     As shown in FIGS. 3 and 7, the suction duct 7 has a cross-sectionally trapezoidal shape. It has side walls 7&#39; which are provided, along their length, with a plurality of apertures 7a through which air is drawn from the outside in the direction D to generate a suctional air flow to which the roll pairs 4a, 5a; 4b, 5b; and 4c, 5c are exposed. As a result, waste material, such as dust or fiber fly freed from the sliver as it is compressed by the roll pairs is entrained by the vacuum stream into the duct 7. In this manner, the guide elements 9a shown in FIG. 4, the roll pairs 4a, 5a, 4b, 5b, and 4c, 5c and the slivers 3a, 3b and 3c are cleaned. The slivers 3a, 3b and 3c drawn from the respective coiler cans 1a, 1b and 1c balloon particularly in case of high sliver-advancing speeds. By virtue of such a motion of the slivers, a substantial amount of dust and fiber fly is released which, particularly at the inlet location of the guide elements 9a where a quieting of the stream is effected, is separated and drawn away by the air stream. 
     Turning to FIG. 2, the lower edge 8&#39; of the closed hood assembly 8 is at a small distance a from the cylindrical face 1&#39; of a coiler can 1. In this manner, the air stream C&#39; drawn in from the outside by the flow in the suction duct 7 is reinforced. Further, the lower edge 8&#39; of the hood assembly 8 is at a vertical distance b underneath the upper edge 1&#34; of the coiler can 1. The lower edge 8&#39; may be positioned as high as the level of the upper edge 1&#34;. 
     In FIG. 5, underneath the intake table 2, two rows of coiler cans 1a&#39;, 1b&#39;, 1c&#39; and 1a&#34;, 1b&#34;, 1c&#34; are shown. The suction duct 7 extends above the intake table 2 which supports the hood element 8a covering one row of the cans and the hood element 8b covering the other, adjacent row. The hood elements 8a and 8b are secured to the suction duct 7 by hinges and are pivotal in the direction of arrows F and G into open and closed positions. FIG. 5 illustrates the hood elements 8a, 8b in phantom lines in their upward, open position. When pivoted downwardly, the hood parts 8a and 8b assume a position as illustrated in FIG. 2. 
     In FIG. 6 the hood is formed by two roller shade-type devices 10a and 10b which may be pulled down into a closed, operative position or rolled up into a withdrawn, inoperative position. 
     In FIG. 7 the hood parts 8a and 8b are shown in their closed position in which they slope downwardly from the suction duct 7 at an angle a to the horizontal whereby the air streams E&#39; and E&#34; are guided towards the openings 7a of the suction duct 7. Terminal portions of the hood parts 8a, 8b are angled, so that in the closed position such terminal portions assume a vertically downward orientation. 
     Turning to FIGS. 8a and 8b, the cross section of the suction duct 7 increases as viewed in the direction of the air flow B. The hood is formed of two hood elements 8a&#39; and 8b&#39; which are secured to the duct 7 and may be affixed thereto in a downwardly sloping orientation (FIG. 8a) or in a substantially horizontal alignment (FIG. 8b). Or, in the alternative, the hood elements 8a&#39;, 8b&#39; may by hinged to the duct 7. The outer lower edges of the hood elements 8a&#39;, 8b&#39; are provided with hinges 11a and 11b, respectively, for carrying terminal flaps 12 (for the hood element 8a) and 13 (for the hood element 8b). The terminal flaps 12 and 13 are pivotal in a vertical plane in the direction of the arrows H and I. FIG. 8a shows the construction in a closed, operating position whereas in FIG. 8b the terminal flaps 12 and 13 assume a raised, generally horizontal, coplanar position in which the hood assembly is open, for example, for the purpose of effecting coiler can replacement. 
     In FIG. 9, the hood elements 8a&#34; and 8b&#34; of the hood are angled elements with rectangularly bent, approximately vertically oriented wall portions to which vertically slidable terminal flaps 14a, 14b are secured which are movable in the direction of the arrows K and L. For such securing purposes the hood elements 8a&#34; and b&#34; are provided with vertical slots 20 into which extend lugs 21 affixed to the respective terminal flaps 14a, 14b. The slots 20 may also serve as inlet openings through which an air stream enters into the inner space defined by the hood. 
     Turning to FIG. 10, the hood structures shown in various embodiments may be mechanically controlled, for example, by driving devices 15 such as a pneumatic pressure cylinder, electric motors or the like. Further, an electronic control and regulating device 26, for example, a microcomputer, is provided, together with a fill level sensing arrangement 16, all connected to the control and regulating device 26 to automatically place the hood assembly into its withdrawn, inoperative position when the sensor device 16 emits a signal indicating, for example, a nearly empty condition of at least one of the coiler cans. 
     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.