Abstract:
A fiber cleaning device is provided for use with a carding machine having a rotating clothing cylinder, a housing surrounding the cylinder, and an opening in the housing for removing impurities. The device has a separating knife with a knife edge for locating in the opening and directed counter to a rotational direction of the cylinder, and a pressure regulating element installed downstream, in the rotational direction of the cylinder, of the separating knife. The pressure regulating element is for adjusting a pressure between the housing and the cylinder such that fiber material accumulation on the knife edge is promoted.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
         [0001]    This application claims priority to German Patent Application No. 101 44 211.4 filed on Sep. 8, 2001, the disclosure of which is incorporated herein by reference.  
         BACKGROUND OF THE INVENTION  
         [0002]    The invention relates to a device for use with a carding machine for cleaning and opening textile fiber material such as, for example, cotton, synthetic fibers, and the like. The device comprises a rotating clothing or wire needle cylinder surrounded by a housing. The cylinder is located downstream of a feeding device and is provided with at least one opening for removing impurities such as trash particles, leaf rests, seed husks, stem rests, sand, and the like. At least one separating knife is arranged near the clothing or the wire needles of the cylinder such that a knife edge of the separating knife is directed counter to the rotational direction of the cylinder. The knife edge is positioned at a downstream end of the opening, in the rotational direction of the cylinder.  
           [0003]    German Patent No. 39 08 834 discloses a device of this type, in which the fiber material collects around the edge of the separating knife. A nep or burl of the fiber material is thicker than the fiber bat on the roller and is pushed onto the knife. This collection of material is known as a “fiber beard”. The fiber beard remains only briefly on the edge of the knife. The neps, burls and husks often slip off of the knife edge, slip through under the knife and follow the cylinder clothing.  
         SUMMARY OF THE INVENTION  
         [0004]    It is an object of the invention to create a device of the aforementioned type that avoids the aforementioned disadvantages and, in particular, permits a lasting and improved removal of the neps, burls and/or husks.  
           [0005]    Particular embodiments of the invention provide a fiber cleaning device for use with a carding machine having a rotating clothing cylinder, a housing surrounding the cylinder, and an opening in the housing for removing impurities. The device has a separating knife with a knife edge for locating in the opening and directed counter to a rotational direction of the cylinder, and a pressure regulating element installed downstream, in the rotational direction of the cylinder, of the separating knife. The pressure regulating element is for adjusting a pressure between the housing and the cylinder such that fiber material accumulation on the knife edge is promoted.  
           [0006]    Due to an increase in the air pressure downstream of the edge of the knife, as seen in the rotational direction of the cylinder, more neps are removed at the edge of the knife. More fibers fit themselves around the knife edge and the neps (the thickened and knotted sections) also fit themselves more clearly around the edge of the knife. A type of fiber beard or “bow wave” is created in front of or on the knife edge. It is preferable if the neps, burls, and husks are positioned on the side of the knife edge opposite the cylinder clothing. The accumulated neps, burls, and husks are thus prevented from again slipping through under the knife and following the cylinder clothing. The foreign bodies (neps, burls, and husks) accumulated and concentrated in this way can then be removed by, for example, suctioning.  
           [0007]    Other embodiments of the invention provide a carding machine. The carding machine has a rotating clothing cylinder, a housing surrounding the cylinder, an opening in the housing for removing impurities, a fiber cleaning device, and a traveling flat having a flat bar. The flat bar has a pressure increasing element that increases a pressure upstream, in the rotational direction of cylinder, of the opening. The fiber cleaning device has a separating knife with a knife edge located in the opening and directed counter to a rotational direction of the cylinder. The fiber cleaning device also has a pressure regulating element installed downstream, in the rotational direction of the cylinder, of the separating knife. The pressure regulating element adjusts a pressure between the housing and the cylinder such that fiber material accumulation on the knife edge is promoted. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]    The invention is explained below in further detail with the aid of exemplary embodiments shown in the drawings, wherein:  
         [0009]    [0009]FIG. 1 is a schematic side elevation view of a carding machine including an example of the invention;  
         [0010]    [0010]FIG. 1 a  is a partial side elevation view of an embodiment of the invention provided with a throttle bar;  
         [0011]    [0011]FIG. 2 is a partial side elevation view of an example of the invention showing a fiber beard with accumulated fibrous impurities such as neps;  
         [0012]    [0012]FIG. 3 is a partial side elevation view of an example of the invention having a wire-needle roller adjacent the knife edge;  
         [0013]    [0013]FIG. 4 is a partial side elevation view of an example of the invention having clothing on a back surface of the knife in the region of the knife edge;  
         [0014]    [0014]FIG. 5 is a partial side elevation view of an example of the invention having a suctioning device adjacent the knife edge;  
         [0015]    [0015]FIG. 6 is a partial side elevation view of an example of the invention having a serrated knife edge;  
         [0016]    [0016]FIG. 7 is a partial side elevation view of an example of the invention having a rotating knife bar adjacent the knife edge;  
         [0017]    [0017]FIG. 7 a  is a partial side elevation view of the serrations of the example shown in FIG. 7;  
         [0018]    [0018]FIG. 8 is a side elevation view of a flat bar with clothing and a flat bar with a pressure beam; and  
         [0019]    [0019]FIG. 9 is a side elevation view of a flat bar with clothing and a pressure beam. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0020]    [0020]FIG. 1 shows a carding machine, for example a high-performance carding machine Model DK 903 manufactured by the company Trutzschler in Mönchengladbach, Germany. The carding machine is provided with feed roller  1 , feed table  2 , licker-ins  3   a,    3   b,    3   c,  main carding cylinder  4 , doffer  5 , stripping roller  6 , crushing rollers  7 ,  8 , sliver element  9 , web trumpet  10 , withdrawing rollers  11 ,  12 , traveling flats  13  with flat bars  14 , can  15  and can holder  16 . Travelling flats move around rollers  13   a  and  13   b.  Cleaning rollers  31 ,  32  will be discussed below. Curved arrows show the rotational directions of the rollers while the operating direction is indicated by arrow A. The device  17   a,    17   b  according to the invention can be positioned, for example, at the location B and/or C on the main carding cylinder  4 . As shown in FIG. 1 a,  a stationary carding element  18 , a suction hood  19   a  with a separating knife  20  and a discharge opening  21 , and a pressure regulating element (in this example, a throttle bar)  17  are provided one behind the other at location B, as seen in rotational direction  4   a,  of the main carding cylinder  4 . Pressure regulating element  17  can also be a carding element with clothing. A similar arrangement can be located at one or more other locations on the carding machine such as, for example, suction hood  19   b  at location C in FIG. 1. Main carding cylinder  4  has cylinder clothing  4   b.  A cover  23  is positioned opposite the cylinder clothing  4   b.  A distance a is the distance of the separating edge  20   a  (see FIG. 2) of the separating knife from the tips of the cylinder clothing  4   b.  A distance b is the distance of the pressure regulating element  17  from the tips of the cylinder clothing  4   b.  Distances a and b are preferably less than a distance c of the cover  23  from the tips of the cylinder clothing  4   b.    
         [0021]    As a result of the arrangement of the pressure regulating element  17  according to FIGS. 1 a  and  2 , a pressure increase is created in the space between the housing  23  and the clothing  4   b  of cylinder  4 . This pressure increase causes more (in particular, fibrous) impurities such as neps and the like to be separated from the desirable fiber material at the knife edge  20   a.    
         [0022]    During operation of the machine, fiber material F builds up on knife edge  20   a  (FIG. 2). A nep or burl (a thickened section or knotted section) is thicker than the desirable fiber bat and is therefore pushed more easily onto the knife  20 . The increased pressure downstream of the knife edge  20   a  helps remove more neps from the desirable fiber bat at the knife edge  20   a.  More fibers will fit themselves around the knife edge  20   a  and the neps also will fit themselves more noticeably around the knife edge  20   a.  This build-up of fibers is referred to as a fiber beard F or a bow wave in front of the knife edge  20   a.  The fiber beard F remains briefly on the knife edge  20   a.  This positions the neps, burls, and husks (herein after referred to as NBH) at the correct location on the knife edge  20   a,  that is, beyond the clothing  4   b.  However, even when the NBH is in this position, it can again slip through underneath the knife  20  and follow the cylinder clothing  4   b.  This disadvantage can be corrected by the invention by processing the fiber beard F at the knife edge  20   a  to discharge the NBH. Increased pressure behind the knife  20  promotes the accumulation of the fiber beard F at the knife edge  20   a.  Mechanical or pneumatic movement of the NBH results in improved discharge of the NBH.  
         [0023]    The invention promotes the removal of NBH by increasing the size of the fiber beard F at the knife edge  20   a  due to the increased pressure downstream of the knife  20 . The increased pressure is created with the aid of a restricted location, for example a throttle bar  17  arranged at a distance of {fraction (14/1000)}″ to the main carding cylinder clothing  4   a,  downstream of the knife  20 . Due to the increased pressure, the fiber beard F is long enough that it can be actively processed, for example, combed out.  
         [0024]    In the example shown in FIG. 3, a wire-needle roller  25  (similar to clothing found on a flat bar) is rotated (in either direction) at the knife edge  20   a  and catches the NBH that accumulates on the knife edge  20   a.  The wire-needle, or other, clothing orientation depends on the rotational direction of the wire-needle roller  25 . A knurled roller can also be used. The roller  25  is preferably cleaned continuously on the side facing away from the main carding cylinder clothing  4   a.  The roller  25  is preferably set into a curved recess  20   b  above the knife edge  20   a.    
         [0025]    In the example shown in FIG. 4, the back of the knife (beyond the clothing) is provided with a micro-clothing  26  for catching the NBH on the knife edge  20   a.    
         [0026]    In the example shown in FIG. 5, the NBH are suctioned, with a directed suctioning flow D, from the fiber beard F on the knife edge  20   a.  To accomplish this suctioning, the knife edge  20   a  is provided with a suctioning device  27  such as, for example, a suctioning box, a suctioning line, or the like. The suctioning can be continuous or intermittent.  
         [0027]    In the example shown in FIG. 6, the knife edge is serrated over its width so that the NBH particles are caught in the teeth  28  and the goods fibers are carried along by the main carding cylinder  4 . The NBH particles are preferably cyclically removed through, for example, suctioning (FIG. 5), combing out (FIG. 3), or the like.  
         [0028]    In the example shown in FIGS. 7 and 7 a,  a roller  29  with a plurality of knife arms  29   a,  each provided with a serrated knife tip  29   b,  is arranged so that a serrated knife tip  29   b  is intermittently inserted into the fiber beard F to remove NBH particles from the knife edge  20   a.  The desirable fibers move past the serrated knife tip  29   b  back into the main carding cylinder  4 . On the side opposite the cylinder clothing  4   b,  the serrated knife tips  29   b  of each knife arm  29   a  of roller  29  are cleaned.  
         [0029]    With the exemplary embodiments shown herein, the removal of NBH particles is improved considerably through the interaction between a larger fiber beard and a special knife edge.  
         [0030]    This interaction can also be realized at other locations of the carding machine. In the example shown in FIG. 8, the clothing  14   a  of a traveling flat  14   1  can be closed off in that the following traveling flat  14   2  is provided with a closing element, e.g. a throttle bar  30 . Also, as shown in FIG. 9, a throttle bar  30 ′, or the like, on a traveling flat  14   3  can be arranged behind the clothing  14   a ′. As a result, a bow wave is created in front of the restricted location (in front of throttle bar  30 ,  30 ′) and the NBH affix themselves to the clothing  14   a,    14   a ′ as a result of the mechanical impact. The NBH are then removed by rotating cleaning rollers  31 ,  32  (see FIG. 1) from the clothing  14   a  of the rotating flat bars  14  of traveling flats  13 .  
         [0031]    The invention has been described in detail with respect to preferred embodiments and it will now be apparent from the foregoing to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects. The invention, therefore, is intended to cover all such changes and modifications that fall within the true spirit of the invention.