Abstract:
A fiber processing machine for forming a fiber lap from fiber tufts, includes a fiber feeding assembly which has a feed roll having a rotary axis; a carrier element extending adjacent and along the feed roll; and a feed tray array cooperating with the feed roll for drawing fiber material into a nip defined between the feed tray array and the feed roll and for discharging the fiber material from the nip. The feed tray array is composed of a series of individual feed trays lined up along the feed roll. Individual, separate rotary supports for mounting each feed tray on the carrier element provide for a pivotal motion of each feed tray in a plane generally perpendicular to the rotary axis of the feed roll.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation of pending U.S. application Ser. No. 09/332,531 filed Jun. 14, 1999. 
    
    
     This application claims the priority of German Application No. 198 26 070.9 filed Jun. 12, 1998, which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     This invention relates to a feed tray assembly in a fiber processing machine which forms a fiber lap (fiber batt), for example, from wool or chemical fiber tufts. The machine includes a fiber feeding device composed of a slowly rotating feed roll cooperating with a feed tray. A rapidly rotating opening roll is disposed immediately downstream of the feed roll (as viewed in the direction of fiber advance). The fiber feeding device and the opening roll withdraw the fiber material from a reserve chute and forward the material to a downstream-arranged device for processing the fiber material. The feed tray assembly includes a feed tray array formed of a plurality of individual feed trays rotatable about an axis. 
     In a known device of the above-outlined type as disclosed, for example, in German Offenlegungsschrift (application published without examination) 34 13 595, in a fiber tuft feeder for a card, above the opening roll which separates the upper chute (reserve chute) from the lower chute (feed chute), a feed roll is disposed which draws the fiber tufts from the upper chute in cooperation with a feed tray array which is composed of a plurality of closely side-by-side arranged individual feed trays. Each feed tray is pivotal about an axis which extends parallel to the feed roll axis. The individual feed trays are pivoted by the fiber tufts to an extent which depends from the mass of the fiber tufts passing through the gap defined by the feed trays and the feed roll. The feed trays are situated at the outlet of the upper chute. The support shaft on which all the individual feed trays are mounted extends beyond the two flanking (outermost) feed trays and is disposed in the narrow, air-impervious side walls of the reserve chute. 
     It is a disadvantage of such a prior art arrangement that the tray-supporting shaft which extends throughout the width of the tuft feeder, sags so that it cannot be used in case of wide roller card feeders which may have a width of over 3 m. It is a further drawback that the distance between the individual feed trays, on the one hand and the feed roll, on the other hand, is altered in an undesired manner. Further, the pressing forces urging the feed trays against the feed roll are not uniform which may lead to changes or misalignments of the clearance between adjoining feed trays, likely to cause operational disturbances. It is a further disadvantage of the prior art arrangements that the feeding device cannot be adapted to different types of fiber material, particularly different fiber lengths. 
     SUMMARY OF THE INVENTION 
     It is an object of the invention to provide a fiber feeding assembly of the above-outlined type from which the discussed disadvantages are eliminated and which, in particular, is operationally reliable and makes possible an exact clamping of the fiber material between the individual feed trays and the feed roll. 
     This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the fiber processing machine for forming a fiber lap from fiber tufts includes a fiber feeding assembly which has a feed roll having a rotary axis; a carrier element extending adjacent and along the feed roll; and a feed tray array cooperating with the feed roll for drawing fiber material into a nip defined between the feed tray array and the feed roll and for discharging the fiber material from the nip. The feed tray array is composed of a series of individual feed trays lined up along the feed roll. Individual, separate rotary supports for mounting each feed tray on the carrier element provide for a pivotal motion of each feed tray in a plane generally perpendicular to the rotary axis of the feed roll. 
     By providing that each individual feed tray has its own rotary support and that all rotary supports are mounted on a common stable support element, a linear alignment of the rotary axes of the individual feed trays is ensured in a simple manner. Between the individual feed trays and the feed roll in all zones the same pressing forces prevail, as related to the axial length units of the feed roll. At the same time, undesired deformations relative to the rotary axes and as concerns the distance between the individual feed trays are avoided whereby the operational reliability and uniformity of the fiber material are improved. 
     The invention has the following additional advantageous features: 
     The individual feed trays and the feed roll are supported independently from one another, and the location of the support for the feed trays and/or the support for the feed roll may be changed relative to one another. 
     The carrier element is an elongated member such as a carrier beam which is hollow, which resists bending and whose opposite ends are supported on the side walls of the machine frame. 
     The carrier element is hollow and has a square or rectangular cross section, it is made of steel and has moments of inertia which are at least approximately identical in a vertical direction, and do not vary to a greater extent than a ratio of 1:1.5. 
     The moments of resistance of the carrier element are similar to one another. 
     Each individual feed tray is biased by a spring or a pneumatic element and all biasing elements are counter supported by the carrier element. 
     With the carrier element and the individual feed trays respective springs are associated which are supported at one end by the carrier element and, at the opposite end, by the respective individual feed tray. 
     Each individual feed tray is rotatably supported at one end thereof. 
     The rotary supports for the individual feed trays are secured to the carrier element or are arranged adjacent thereto. 
     For each feed tray spring a holding element (such as an angled member) is provided and each individual feed tray is mounted on an individual holding element. 
     The springs and the rotary supports of the individual feed trays are positioned close to the corners of the carrier element. 
     The pressing forces between the individual feed trays on the one hand and the feed roll on the other hand are at least approximately identical. 
     At least one abutment is provided for limiting the rotary motion of the individual feed trays and the abutment is fixed relative to the carrier element. 
     The feed trays are extruded members made, for example, of aluminum or an aluminum alloy. 
     The surface of each individual feed tray oriented towards the fiber material is wear resistant and is, for example, a sheet metal of high grade steel or the feed tray surface is plated. 
     The sheet metal is bonded to the feed tray surface by gluing. 
     The opening roll is a preliminary roll of a roller card unit. 
     An additional preliminary roll is associated with the preliminary roll of the roller card unit. 
     The support element is situated externally of the feed chute. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic side elevational view of a machine assembly formed of a roller card and a roller card feeder incorporating the invention. 
     FIG. 2 is a fragmentary perspective view of a feed roll as well as individual feed trays mounted on a carrier element according to the invention. 
     FIG. 3 is a sectional side elevational view of the roller card feeder of FIG. 1, shown on an enlarged scale and illustrating additional details. 
     FIG. 4 a  is a sectional side elevational view of the upper part of the construction shown in FIG. 2, wherein the fiber feeding assembly according to the invention is located at the upper feed chute. 
     FIG. 4 b  is a sectional view taken along line IVb—IVb of FIG. 4 a.    
     FIG. 4 c  is a sectional view taken along line IVc—IVc of FIG. 4 a.    
     FIG. 5 is a sectional side elevational view of the lower part of the construction shown in FIG. 2, wherein the device according to the invention is located at the lower feed chute. 
     FIG. 6 is a perspective view illustrating the mounting of carrier elements to lateral machine frame walls. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Turning to FIG. 1, upstream of a roller card unit  1  a fiber feeder is located, having a vertically oriented reserve chute  2  charged from above with a mixture I of air and finely opened fiber material (fiber tufts). Such charging may be effected, for example, by a condenser or by a supply and distributor duct  3 . In the upper region of the reserve chute  2  air outlet openings  4  are provided through which the transporting air II leaves the reserve chute after being separated from the fiber tufts III by means of a suction device  5 . The lower end of the reserve chute  2  is closed off by a feed roll  6  which has a rotary axis  6 ′, a direction of rotation  6   a  and which cooperates with a feed tray array  7  formed of a plurality of individual feed trays  7   a  as shown in FIG. 4 b.  The fiber material III is advanced from the reserve chute  2  by means of the slowly rotating feed roll  6  to a rapidly rotating opening roll  8  having pins  8   b  or a sawtooth clothing on its circumferential surface. One part of the circumference of the opening roll  8  faces a lower feed chute  9 . The opening roll  8  which rotates in the direction of the arrow  8   a  advances the fiber material III into the lower chute (feed chute)  9 . The feed chute  9  has at its lower end a withdrawing roll  10  which advances the fiber material to the roller card unit  1 . The fiber feeder may be an EXACTAFEED model, manufactured by Trutzschler GmbH &amp; Co. KG, Monchengladbach, Germany. 
     Also referring to FIG. 3, the lower part of the walls of the feed chute  9  are provided with air outlet openings  11  to separate the air stream V from the fiber stream VI. At the top, above the feed roll  6 , the feed chute  9  is in communication with a duct  12  coupled to the output of a blower  32 . The rotating feed roll  6  and the opening roll  8  continuously advance the mixture IV of air and fiber material at a certain flow rate into the feed chute  9  and an identical quantity of fiber VI is drawn from the feed chute  9  by the withdrawing roll  10  which cooperates with a feed tray array  14  composed of a plurality of individual feed trays  14   a  (only one is visible) and which advances the fiber material from the feed chute  9  to the roller card unit  1 . The blower  32  drives an air stream from the duct  12  onto the fiber material in the feed chute  9  for ensuring a uniform densification of the fiber material and for maintaining constant the flow rate thereof. The opening roll  8  and the feed roll  6  are surrounded by respective parts  9   c  and  9   d  of the chute  9 . The chute parts  9   c  and  9   d  conform to the circumference of the rolls  6  and  8 . As viewed in the direction of rotation  8   a  of the opening roll  8 , the chute part  9   c  is interrupted by a separating opening for the fiber material. The separating opening is adjoined by the wall region which extends to the feed roll  6 . 
     Also referring to FIG. 2, at the lower end of the wall zone facing the feed roll  6  a feed tray (intake tray) array  7  is arranged. The edge of the feed (intake) tray array  7  is oriented in the rotary direction  8   a  of the opening roll  8 . The plane which contains the rotary axes of the feed roll  6  and the opening roll  8  is oriented at an oblique angle to the vertical plane which contains the rotary axis of the opening roll  8 . As viewed above the axis of the opening roll  8 , the oblique plane is offset relative to the vertical plane in the direction of rotation  8   a  of the opening roll  8 . The reserve chute (upper chute)  2  includes wall elements  30   a  which are displaceable in the direction of the chute depth as illustrated in FIG. 4 c.  The wall portions ll a  of the feed chute  9  which contain the air outlet openings  11  are formed in sections and are supported on the side wall  9   b  for rotation in the direction of the arrows D and E. Each section ll a  is associated with a setting device  34 , such as a pneumatic cylinder. This arrangement allows a sectionwise adjustment of the depth of the feed chute  9  in the region where the fiber lap (fiber batt) is formed. 
     The feeding device for the roller card unit  1  is constituted by the withdrawing roll  10  and the feed tray array  14  at the lower end of the feed chute  9 . Downstream of the feed roll  10  and the feed tray array  14 , as viewed in the direction of fiber advance A in the roller card unit  1 , there are provided a first preliminary roll  15 , a second preliminary roll  16 , a licker-in  17 , a transfer roll  18 , a main cylinder  19 , a doffer  20  and a stripping roll  21 . With the licker-in  17  and the main cylinder  19  two and, respectively, six roll pairs are associated, each formed of a working roll  22   a  and a reversing roll  22   b.  Two calender rolls  23  and  24  are disposed immediately downstream of the stripping roll  21  to cooperate therewith. The rotation of the individual rolls is indicated by the curved arrows drawn therein. 
     As shown in FIG. 2, a carrier beam (carrier element)  25  is provided which is made, for example, of structural steel and which has a hollow, rectangular cross-sectional configuration. The carrier beam  25  is stable and resists bending. It has a length of, for example, 5 m or more and extends parallel to and throughout the width of the machine. A plurality of individual feed trays  7   a  are secured by means of respective rotary supports  26  to a side wall  25   a  of the carrier beam  25  between the carrier beam  25  and the feed roll  6 . Each feed tray  7   a  is supported by a respective compression spring  27  on a throughgoing angle member  28  which is secured to the bottom wall  25   c  of the carrier beam  25 . Further, abutment elements  29  are provided which limit the excursion of the respective feed trays  7   a.    
     Turning to FIGS. 3 and 4 c,  the side wall  2   a  of the upper reserve chute  2  has a plurality of wall elements  30  which are displaceable in the direction of the arrows B, C whereby the depth a of the reserve chute  2  may be zonewise adjusted. Each wall element  30  is movable by its own setting device, such as a pneumatic power cylinder  31  coupled to an electronic control and regulating device (such as a microcomputer)  38 . The height of the wall elements  30   a  essentially corresponds to the region where the fiber lap is formed from the fiber tufts. As shown in FIGS. 1 and 3, the carrier beam  25 , together with the rotatable feed trays  7   a,  is arranged at the lower end of the wall  2   b  of the reserve chute (upper chute)  2 . At the lower end of the wall  9   a  of the feed chute  9  a further carrier beam  33  is arranged which, similarly to the carrier beam  25 , may be made of structural steel. The carrier beam  33  rotatably supports feed trays  14   a  which form a feed tray array  14 . A fan  32  introduces air into the region of the feed roll  6  through the duct  12 . 
     FIG. 4 b  shows that the carrier beam  25  which has a length of approximately 5 m, is disposed in the region of the lower end of the chute side wall  2   b  and extends throughout the width b of the machine and is held in side plates  39   a,    39   b  of the machine frame by supporting components  25 ′ mounted on the side plates  39   a,    39   b  and being adjustable relative thereto. The carrier beam  25  rotatably supports five individual feed trays  7   a  each being 1 m wide and made of an extruded aluminum member having a wear-resistant surface exposed to the fibers. The feed trays  7   a  are rotatable in the direction of the arrows F, G by virtue of the rotary supports  26  affixed to the side wall  25   a  of the carrier beam  25 . 
     As shown in FIG. 4 a,  to the rearward face of each feed tray  7   a  a respective angle member  35  is affixed which is supported on a respective angle member  36  (affixed to the face  25   b  of the carrier beam  25 ) by a respective compression spring  27 . Thus, by virtue of this arrangement each feed tray  7   a  of the feed tray array  7  is urged toward the feed roll  6  by its spring  27  in the direction of the arrow F and each feed tray  7   a  may pivot individually against the force of the spring  27  in the direction of the arrow G as urged by the force exerted on the feed tray  7   a  by the throughgoing fiber material. Between the movable angle member  35  and the fixed angle member  36  an inductive path sensor  37  is arranged. The path sensor  37  has a plunger armature  37   a  cooperating with a plunger coil  37   b  which is coupled to the electronic control and regulating device  38  as shown in FIG. 4 c.  Upon pivotal motion of the feed trays  7   a  and the resulting excursion of the plunger armature  37   a  of the respective inductive path sensor  37  in the direction of the arrows H, I, an electric pulse is generated which represents the excursions which are performed by the feed trays  7   a  in case the fiber thickness varies as the fibers pass through the feed gap defined by the feed roll  6  and the respective feed trays  7   a.  As shown in FIG. 4 b,  the carrier beam  25  with the feed trays  7   a,  on the one hand, and the feed roll  6 , on the other hand, are mutually independently secured to the rigid side plates  39   a,    39   b  of the machine. In this manner the carrier beam  25  with the feed trays  7   a  may be displaced locally relative to the feed roll  6  so that in case of different fiber material, or during maintenance work or the like the distance and thus the intake gap defined between the feed trays  7   a  and the feed roll  6  may be altered and adapted as required. 
     As shown in FIG. 5, in the region of the lower end of the side wall  9   a  of the feed chute  9  an approximately 5 m long carrier beam  33  is provided which extends over the entire width of the machine. This embodiment has sixteen individual feed trays  14   a  which form a feed tray array  14  and each has a length of 250 mm. Each feed tray  14   a  is an extruded aluminum component having a wear-resistant surface in the area where it is exposed to the fibers. The wear-resistant surface is provided by coating, by plating with high grade steel, or the like. The feed trays  14   a  are, at one of their ends, secured to the side wall  33   a  of the carrier beam  33  by means of respective rotary supports  40  to be rotatable in the direction of the arrows K, L. On their side oriented away from the fibers, each feed tray  14   a  is secured to one leg of respective angled members  41 , whereas the other leg of the angled member  41  supports a respective spring  42  which presses against a respective angled member  43  secured to the bottom wall  33   c  of the carrier beam  33 . To each rotary support  40  one end of a respective, generally U-shaped lever  44  is affixed which thus rotates as a unit with its associated rotary support  40  and which extends above the top wall  33   d  of the carrier beam  33 . A respective support element  44 ′ is affixed to the side wall  33   b  of the carrier beam  33 . For each feed tray  14   a,  between the free end of the respective lever  44  and the support element  44 ′ an inductive path sensor  45  is provided which is formed of a plunger armature  45   a  and a plunger coil  45   b  coupled to the electronic control and regulating device  38 . In this manner, upon excursions of the feed trays  14   a  and a corresponding movement of the respective path sensor  45  in the direction of the arrows M, N, electric pulses are generated which represent the excursions of the respective feed trays  14   a  when the thickness of the fiber material passing through the intake gap changes. 
     FIG. 6 illustrates the securement of the ends of the carrier beams  25  and  33  to the inner faces of the machine side walls  39   a,    39   b  by means of screws which may pass through slots of a mounting plate. 
     The above-described fiber tuft feeder combined with the roller card unit  1  includes the regulating system controlling the fiber lap profile for the roller card unit. Two systems are formed, namely the assembly formed of the feed roll  6  and the feed tray array  7  which close off the upper feed chute  2  and the assembly formed of the withdrawing roll  10  and the feed tray array  14  which closes off the lower end of the feed chute (lower chute)  9 . In both systems a series of feed trays ( 7   a  and  14   a ) are used which cooperate with the feed roll  6  and the withdrawing roll  10 , respectively. The feed tray widths and the zone division may be varied and adapted to the requirements. 
     Between the feed trays  7   a  and the feed roll  6  and the feed trays  14   a  and the withdrawing roll  10  in all zones the same pressing forces relative to the roll length units (for example, 10 cm) are preserved and deformations of a few millimeters are permitted. 
     All functional elements with the exception of the feed roll  6  and the withdrawing roll  10  are mounted on the carrier beam  25  or  33 , while it is ensured that the force paths (represented by the carrier beams  25 ,  33 , the rotary supports  26 ,  40 , the series of feed trays  7   a,    14   a,  the springs  27 ,  42 ) are very short and all elements are situated in the vicinity of the corners of the cross-sectionally rectangular carrier beams  25 ,  33 . 
     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.