Patent Publication Number: US-6220793-B1

Title: Apparatus for guiding pneumatically conveyed textile fiber tufts

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the priority of German Application No. 198 20 914.2 filed May 9, 1998, which is incorporated herein by reference. 
     FIELD OF THE INVENTION 
     This invention relates to an apparatus for channeling pneumatically transported textile fiber tufts such as cotton or chemical fiber tufts from a main conduit into at least one of two branch conduits by movable routing gates. In the region of the location where the branch conduits extend from the main conduit, an aperture for intake air is provided whose control element (closing and opening element) is coupled with the drive of the routing gates. 
     TECHNOLOGY REVIEW 
     When fiber tufts are conveyed pneumatically, the fiber material is entrained by a conveying gas, for example, air, through a conduit which introduces the fiber tufts into a fiber processing machine. Fiber tufts are often processed by a fiber processing line composed of a plurality of simultaneously operating, serially and/or parallel-connected fiber processing machines, such as fiber bale openers, cleaners, card feeders, carding machines and mixers which are interconnected by tuft conveying conduits. For supplying the pneumatically conveyed tufts to parallel-connected machines, from a main conduit two branch conduits extend, and a 2-way tuft distributing device (channeling or routing device) is inserted between the main conduit and the branch conduits. 
     The 2-way distributing device includes two routing gates, by means of which the fiber tuft-laden conveying stream flowing through the main conduit may be directed into either the first branch conduit (by closing the second branch conduit) or into the second branch conduit (by closing the first branch conduit) or into both branch conduits (by maintaining both branch conduits open). The main conduit and the two branch conduits have essentially identical diameters. If the entire conveying stream is channeled into only one of the two branch conduits, the flow rate in the active branch conduit is identical to that in the main conduit, that is, the entire conveying air quantity of the main conduit is available for conveyance in the branch conduit. If, however, the conveying stream is split to flow in both branch conduits, then in each branch conduit the flow rate of air is only one half of that in the main conduit, and consequently, such halved flow rates may be insufficient to fulfill its conveying function of air for the after-connected fiber processing machines. Therefore, in the region of the 2-way distributing device, as a rule, at least one air intake opening is provided through which an air quantity is drawn such that in both branch conduits the flow rate of air will essentially equal that in the main conduit. The air intake opening is closed if fiber tufts are conveyed only in one of the two branch conduits. 
     In a known device the intake opening is provided in the ceiling wall of the 2-way distributing device. Each routing gate is rotatably supported along one edge thereof and each is adjoined by a closure element. If the conveying stream is directed into only one of the two branch conduits, the other branch conduit is closed by one of the routing gates and at the same time the associated closure element obturates the air intake opening. The same applies to the other branch conduit. When the conveying stream flows in both branch conduits, in which case the two routing gates maintain both branch conduits open, the two closure elements coupled with the respective routing gates are both spaced from the air intake opening which thus remains open. 
     Such a conventional arrangement is disadvantageous in that it uses additional closure elements and further, their mechanical operation involves substantial structural outlay. Complex structure, assembly and substantial spatial requirement are particular drawbacks. It is a further disadvantage that the flat closure elements are situated above one another and therefore cause certain leakage losses. 
     SUMMARY OF THE INVENTION 
     It is an object of the invention to provide an improved flow channeling device of the above-outlined type from which the discussed disadvantages are eliminated and which is structurally particularly simple and provides for a better guidance of the air stream. 
     This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the device for channeling a pneumatically conveyed fiber tuft stream includes a housing defining a chamber; a main conduit merging into the chamber for guiding the fiber tuft stream into the chamber; first and second branch conduits extending from the chamber for guiding the fiber tuft stream out of the chamber; first and second air intake openings provided in the housing for allowing air, situated externally of the main conduit, to be drawn into the first and second branch conduits; and a routing gate assembly disposed in the chamber and including first and second routing gates each having a surface cooperating with respective first and second air intake openings. The routing gate assembly has a first operational state for channeling the flow from the main conduit simultaneously into the first and second branch conduits; a second operational state for channeling the flow from the main conduit solely into the first branch conduit; and a third operational state for channeling the flow from the main conduit solely into the second branch conduit. In the second and third operational states one of the first and second routing gates blocks directly one of the first and second air intake openings with the surface of the routing gate. 
     By virtue of the fact that each air intake opening may be opened and closed by the associated routing gate itself, each routing gate performs simultaneously several functions: it channels the fiber stream, blocks or opens a branch conduit and blocks or opens the associated air intake opening. In contrast to the known device, separately provided closure elements and their coupling to the routing gates are dispensed with. In addition to the simplification of structure and assembly as well as space saving, a further advantage of the invention resides in the elimination of leakage losses, because each routing gate itself provides for a reliable closure of its own air intake opening. 
     The invention has the following additional advantageous features: 
     At least one pneumatic cylinder is used for pivoting the routing gates. 
     The size of the air intake opening is adjustable and is controlled by a slide or the like. 
     Between each routing gate and the associated air intake opening a seal is provided which is arranged on that surface of the routing gate which is oriented towards the air intake opening or is arranged in the inner wall face of the housing in the region of the air intake opening. 
     The wall faces which contain the air intake openings and the associated routing gates are oriented to one another at an acute angle when conveyance in both branch conduits takes place. 
     During conveyance in one branch conduit, one routing gate hermetically closes the other branch conduit and the other routing gate hermetically closes the air intake opening associated with the active branch conduit. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic top plan view of a spinning preparation line incorporating the invention. 
     FIG. 2 a  is a sectional top plan view of a preferred embodiment of the invention. 
     FIG. 2 b  is a side elevational view of the structure shown in FIG. 2 a.    
     FIG. 2 c  is a partial sectional view taken along line IIc—IIc of FIG. 2 a.    
     FIGS. 3 a,    3   b  and  3   c  are sectional top plan views showing different operational positions of the preferred embodiment. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 schematically shows a spinning preparation (fiber processing) line which is composed of an automatic bale opener  1  which may be, for example, a BLENDOMAT BDT 020 model manufactured by Trützschler GmbH &amp; Co. KG, Mönchengladbach, Germany, a high-capacity condenser  2 , fiber-transporting blowers  3 ,  7  and  8 , multiple mixers  4 ,  9  and  11 , cleaners  5 ,  10  and  12  and a 2-way fiber flow distributing device (routing or channeling device)  6  structured according to the invention. The individual machines of the fiber processing line are interconnected by pneumatic conduits through which fiber tufts are pneumatically conveyed by the blowers as they are removed from the fiber bales  1   a  by the fiber bale opener  1 . The fiber tufts first pass through the main conduit  13  and then are directed into the branch conduit  14  and/or  15  by means of the channeling device  6 . The direction of fiber processing in the fiber processing line is designated by the arrow A. 
     The 2-way distributing device  6 , as shown in FIG. 2 a,  has a main conduit  13  and two branch conduits  14  and  15 . The fiber tuft/air mixture symbolized by the arrow B enters the 2-way distributing device  6  and, dependent upon the position of the routing structure to be discussed in greater detail later, the fiber tuft/air mixture exits the device  6  through the branch conduit  14  as a stream C and/or through the branch conduit  15  as stream D. 
     In the inner chamber of the distributing device  6  two routing gates  18  and  19  are disposed which are cantilevered to respective housing side walls  6   a  and  6   b  by respective pivot pins  20  and  21  for pivotal motions. Air intake openings  22  and  23  are provided in the respective walls  6   a  and  6   b  to face the associated routing gates  18  and  19 . 
     As seen in FIG. 2 b,  on the side wall  6   b  a slide  24  is mounted which, by shifting it in the direction of the arrows G and H varies the size (air passage area) of the air intake opening  23 . The other air intake opening  22  may be similarly controlled by a slide (not shown) mounted on the side wall  6   a.    
     Turning to FIG. 2 c,  above the top housing wall  6   c  of the device  6  a pneumatic cylinder  26  is arranged whose push rod  26   a  is coupled, for example, by a non-illustrated crank or a rack-and-pinion device, to the pivot pin  20  of the routing gate  18 . In this manner, the pivot pin  20  may be rotated and thus the routing gate  18  may be swung in the direction of the arrows I, K as shown in FIG. 3 c.  A similar, non-illustrated pneumatic driving arrangement is associated with the routing gate  19  to swing the same in the direction of the arrows L and M as likewise illustrated in FIG. 3 c.  The pneumatic cylinders are coupled to a non-illustrated electronic control and regulating device or a switching device by means of which the position of the routing gates  18  and  19  may be set. 
     FIGS. 3 a,    3   b  and  3   c  show three different settings of the fiber distributing device  6 . 
     According to FIG. 3 a  the routing gates  18  and  19  are pivoted into such a position that both branch conduits  14  and  15  communicate with the main conduit  13  and further, the routing gates  18  and  19  are spaced from the respective air intake openings  22  and  23 , since the routing gates  18  and  19  are inclined at respective acute angles α and β to the respective wall faces  6   a  and  6   b.  In this position of the routing gates  18  and  19  the fiber tuft conveying air stream is directed simultaneously into both branch conduits  14  and  15 . Further, the air intake openings  22  and  23  are open and, as a result, intake air streams E and F are admitted into the inside of the distributing device  6 . Consequently, the flow rate of air in each branch conduit  14  and  15  remains the same as the flow rate in the main conduit  13 . 
     In the operational position of FIG. 3 b,  the routing gate  19  is pivoted further away from the wall  6   b  and closes airtight the branch conduit  15  in cooperation with the dividing bulkhead  6   d  of the distributing device  6 . Such a blockage of the branch conduit  15  also hermetically separates the air intake opening  23  from the main conduit  13  and the branch conduit  14 , since the air intake opening  23  is situated in the branch opening  15 . The routing gate  18 , in contrast, is moved towards the wall  6   a  to lie flat thereagainst and thus hermetically closes the air intake opening  22 . In this operational position the pneumatically conveyed fiber tuft stream passes solely through the branch conduit  14 . 
     In the operational position of FIG. 3 c,  the routing gate  18  is pivoted further away from the wall  6   a  and closes airtight the branch conduit  14  in cooperation with the dividing bulkhead  6   d  of the distributing device  6 . Such a blockage of the branch conduit  14  also hermetically separates the air intake opening  22  from the main conduit  13  and the branch conduit  15 , since the air intake opening  22  is situated in the branch opening  14 . The routing gate  19 , in contrast, is moved towards the wall  6   b  to lie flat thereagainst and thus hermetically closes the air intake opening  23 . In this operational position the pneumatically conveyed fiber tuft stream passes solely through the branch conduit  15 . 
     As shown in FIGS. 3 b  and  3   c,  the air intake openings  22  and  23  are surrounded by a respective rubber or elastomer sealing ring  28  and  29  supported on the respective side walls  6   a  and  6   b.  In this manner an airtight closure of the air intake opening  22  by the routing gate  18  (FIG. 3 b ) or an airtight closure of the air intake opening  23  by the routing gate  19  (FIG. 3 c ) is obtained. 
     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.