Abstract:
A system for the needle treatment of a conveyable fiber bat is provided with at least one conveying device having a plurality of needles that can be inserted into and withdrawn from a fiber bat. At least one rotating cylinder is provided to make possible a high needle-treatment speed and a uniform structure of the needle-felted fiber bat. The outside of this rotating cylinder forms a conveying surface for the fiber bat. The needles can pass through the conveying device from the inside toward the outside. The needles penetrate the fiber bat perpendicular to the conveying direction and then withdraw. The outside of the rotating cylinder, the fiber bat, and the needles have a similar speed in the conveying direction during the needle-treatment.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the priority of German Patent Application No. 101 40 864.1 filed on Aug. 21, 2001, the disclosure of which is being incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     The invention relates to a system for the needle-treatment of a conveyable fiber bat, and more particularly to a system which includes at least one conveying device having a plurality of needles which are pushed into and subsequently withdrawn from the fiber bat. 
     The fiber bat is subjected to tension during fiber-bat processing when the needles, which are inserted into the fiber bat during the needle-treatment, restrain a continuous conveyance of the fiber bat. This tension can lead to an undesirable stretching of the fiber bat in the conveying direction. U.S. Pat. No. 5,909,883A discloses a system in which the withdrawing roller drive is controlled so that the conveying speed is reduced during the needle intervention to take into account the tension on the fiber bat which increases when the needles penetrate into the material. However, this is tied to a comparably high design and control expenditure. Less complicated means for lowering the tensile stress of the fiber bat during the needle insertion are disclosed in Austrian Patent No. 259,246B1, in which one of the two rollers of a roller pair is designed with diametrically opposite arranged driver cams for the fiber bat. In dependence on the lift frequency of the needle board, the roller is operated such that a frictional connection between conveying rollers and fiber bat exists only if the needles of the needle board release the fiber bat. Such an intermittent conveying drive for the fiber bat represents an advantageous condition for a needle-treatment of the fiber bat with little tension. However, this intermittent conveying effect also requires a uniform thickness of the fiber bat that cannot be ensured in practical operations. Unavoidably thick and thin areas in the fiber bat result in irregularities in the advancement of the fiber bat and thus also in an irregular needle-treatment. Furthermore, thickened areas in the fiber bat can result in damage to the fiber bat surface, caused by the driver cams of one of the conveying rollers impacting on the fiber bat, and can lead to a mechanical overload of these conveying rollers, in particular in the bearing region. Another disadvantage is that a high operating speed is not possible with the known intermittent operation of the needle. According to a prior suggestion, the needles are rigidly arranged on the outside surface of a belt that circulates endlessly around two deflection rollers. In the process, a relative movement occurs between needles and fiber material, which pulls the fiber material out of shape. Specifically, when the needles are pushed in and pulled out of the fiber material at the two deflection locations, relative movements between the needles and the fiber material occur because of the slanted positioning of the needles relative to the fiber material. These movements lead to a stretching in the conveying direction and, in particular, to an irregular structure of the fiber material. 
     SUMMARY OF THE INVENTION 
     It is an object of the invention to provide a device of the aforementioned type that avoids the above-mentioned disadvantages and, in particular, makes it possible to have a high needle-treatment speed and a uniform structure of the needle-treated fiber bat. The conveying device can form part of a needle-treatment system. 
     The above and other objects are achieved according to the invention by the provision of a system for performing a needle treatment operation on a conveyable fiber bat, comprising: at least one circulating endless conveying device having an outside constituting a conveying surface for the fiber bat and an inside; a plurality of wire needles positioned for penetrating the conveying surface from the inside toward the outside and back again, and for being pushed into and withdrawn from the fiber bat; and, means for moving the conveying surface, the fiber bat, and the needles at the same speed during the needle-treatment operation. 
     A high needle-treatment speed and a uniform fiber bat structure are attained with the conveying device according to the invention since the conveying surface or surfaces, the fiber bat, and the needles, during penetration and withdrawal, have the same speed in the conveying direction; moreover, the needles penetrate and are withdrawn from the fiber bat in a direction perpendicular or nearly perpendicular to the fiber bat conveying direction during the needle-treatment operation. A careful and effective needle-treatment of the fiber bat, i.e., the fiber material, thus occurs without any relative speed between the fiber bat and the needles during the conveying operation. The conveying device imparts this careful needle-treatment to a range of fiber bats, including thick fiber bats and fiber bats with short fibers. A high throughput speed can be attained with the conveying device. The extended penetration phase contributes to the high throughput speed. Further advantages of the device are low weight, compact design, and low noise during operation. The design of the device permits a modular construction. The needle treatment can be realized on one side or on two sides of the fiber bat. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of a roller-carding unit with a card unit feeder and the conveying device according to the invention. 
     FIG. 2 is a side view of a floccule feeder directly connected to the conveying device according to the invention. 
     FIG. 3 a  is a sectional side view of an embodiment of the conveying device shown in FIG. 3 b.    
     FIG. 3 b  is a partial sectional front view of the conveying device shown in FIG. 3 a.    
     FIGS. 4 a  through  4   c  are sectional side views of the of the conveying device which show the position of components of the conveying device at successive times. 
     FIG. 5 is a side view of the conveying device which includes a circulating endless perforated belt. 
     FIG. 6 a  is a perspective view of a portion of the endless perforated belt depicted in FIG.  5 . 
     FIG. 6 b  is a side view of a drive mechanism for the endless perforated belt. 
     FIG. 7 is a perspective view of an alternate embodiment of the endless perforated belt. 
     FIG. 8 a  is a side view of a plurality of serially connected conveying devices. 
     FIG. 8 b  is a block diagram of a common electronic control connected to drive motors and drive mechanisms for moving the needles associated with a plurality of conveying devices according to the invention. 
     FIG. 9 a  is a sectional side view of another embodiment of the conveying device according to the invention. 
     FIG. 9 b  is a partial sectional front view of the embodiment of the conveying device in FIG. 9 a.    
     FIG. 10 is a block diagram of a common electronic control connected to drive motors and drive mechanisms for moving the needles associated with a conveying device according to the invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows a roller-carding feeder  11  in conjunction with a roller-carding unit  1 . The roller-carding feeder  11  will first be described. A vertical reserve chute  2  is fed from above with the finely broken up fiber good I, for example via a condenser and through a feeding and distribution line  3 . Air outlet openings  4 ′ and  4 ″ are provided in an upper region of the reserve chute  2  through which transport air II is pulled by a suctioning device  5  following separation from fiber goods or floccules III. A feed roller (intake roller)  6  operating jointly with a feeding trough  7  closes off a lower end of the reserve chute  2 . With this slow-rotating feed roller  6 , the fiber goods III from the reserve chute  2  are supplied below to a fast-moving opening roller  8 , provided with pins or saw-tooth wire, and making contact along a portion of its circumference with a lower feeding chute  9 . The opening roller  8 , rotating in the direction of arrow  8   a , conveys the fiber goods III into the feeding chute  9 . The feed roller  6  rotates slowly in a clockwise direction (arrow  6   a ) and the opening roller  8  rotates in a counterclockwise direction (arrow  8   a ), so that opposite rotational movements are realized. The feeding chute  9  is provided at the lower end with a withdrawing roller  10 , rotating in the direction shown by the drawn arrow, and a feed trough  14  which places the fiber goods into the roller-carding unit  1 . An example of this roller-carding feeder  11 , is a SCANFEED unit manufactured by the company Trützschler in Mönchengladbach, Germany. 
     The feed roller  10  and the feed trough  14  of the roller-carding feeder  11  are followed in the conveying direction A of the roller-carding unit  1  by a first uptake roller  16   1 , a second uptake roller  16   2 , a licker-in cylinder  17 , a transfer roller  18 , and a main carding cylinder  19 . Two roller pairs  16   1  an  16   2  are associated with the licker-in cylinder  17  and six roller pairs are associated with the main carding cylinder  19 ; each roller pair consists of a stripping roller  21  and a clearer  22 . Immediately adjoining and cooperating with the main carding cylinder  19  is a doffer  20  and a stripping roller  21  which serves as a calender roller. Two calender rollers  23  and  24  follow the stripping roller  21 . The conveying device  15  according to the invention is located downstream of the calender rollers  23  and  24 . 
     Alternately, the conveying device  15  according to the invention can be installed downstream of an aerodynamic fiber-bat former (not shown herein), instead of downstream of a roller-carding unit  1 . The conveying device  15  can also follow a carding machine provided with at least one crushing cylinder for creating a heavier fiber bat. 
     According to FIG. 2, a floccule feeder  26 , for example, a SCANFEED FBK 5000, manufactured by the company Trützschler in Mönchengladbach, Germany, is directly connected to the conveying device  15 . Transfer devices  25 , e.g. circulating endless conveying belts and conveying rollers can be arranged between the floccule feeder  26  and the conveying device  15  according to the invention. An operating width of five meters is possible. 
     FIG. 3 a  is a sectional side view of the conveying device and corresponds to the section IIIa taken through FIG. 3 b . FIG. 3 b  is a partial sectional front view of the conveying device and corresponds to the section IIIb taken through FIG. 3 a.    
     According to FIG. 3 a , a rotating cylinder  26  rotates in the direction of arrow  26 ′ and is driven by a drive motor  27 . The fiber bat  37  moves in the direction indicated by arrow C towards the rotating cylinder  26 , on the surface of the outer shell surface of the rotating cylinder  26 , and away from the rotating cylinder  26  in the direction indicated by arrow D. A plurality of openings  28  penetrate through the outer shell of rotating cylinder  26 , which can be a tubular body. Four longitudinal rows of openings  28  are arranged over the circumference of the rotating cylinder  26 . As shown in FIG. 3 a , the rows are equally spaced at 90° angles around the rotating cylinder axis  29 . As seen in FIG. 3 b , the openings  28  within a row are arranged side-by-side. Within the rotating cylinder  26  are four rows of radially moveable needles  30 . The rows are arranged equally spaced at 90° angles around the rotating cylinder axis  29 . As seen over the width of the rotating cylinder  26  (see FIG. 3 b ), each row contains a plurality of needles  30 , arranged side-by-side. Each needle row  30   1 ,  30   2 ,  30   3 , and  30   4  is constrained by two side guides between which the needles  30  can move back and forth in the direction of arrows A and B along a straight line extending between an opening  28  and the rotating cylinder axis  29 . The free end of needles  30  can be pushed through and withdrawn from the openings  28 . The other end of the needles  30  in a needle row is embedded in a needle board  31 ; each needle row has an associated needle board. One end of a connector rod  32  is mounted such that it can pivot on a needle board  31  and the other end such that it can rotate on a needle-actuation shaft  33 ; each needle board has at least one associated connector rod  32 . The rotating cylinder  26  is provided on each of its two ends with locally fixed end plates only  34   a  is shown in FIG. 3 b . A bearing  35   a  is provided between the circumferential face of the end plate  34   a  and the inside shell surface of the rotating cylinder  26 . A similar bearing is provided at the other end of the rotating cylinder  26  between the non-illustrated end plate and the inside shell surface of the rotating cylinder. The needle-actuation shaft  33  is received in the end plates. The rotating cylinder axis  29  and the needle-actuation shaft axis  36  are arranged parallel with respect to each other with a distance a between them. 
     FIGS. 4 a  through  4   c  show that during the needle-treatment operation the fiber bat  37  initially moves in a straight line tangentially towards the rotating cylinder  26 , as indicated by arrow C, in order to receive needle treatment. Subsequently, the fiber bat  37  moves circumferentially with the outer shell surface  26 ″ of the rotating cylinder  26  as shown by arrow E. Finally, the fiber bat  37  moves once more in a straight line away from rotating cylinder  26  in the direction of arrow D. The rotating cylinder  26  rotates with a high speed in the direction of arrow  26 ′. According to FIG. 4 a , at point in time t 1 , the needles  30  in the needle row  30   1  are positioned completely inside of the rotating cylinder  26 . The needles  30  in the needle row  30   2  penetrate the openings  28   2  and start to penetrate the fiber bat  37  in the direction of arrow A. The needles  30  in the needle row  30   3  completely penetrate the fiber bat  37 , whereas the needles  30  in the needle row  30   4  are in the process of being withdrawn from the fiber bat  37  in the direction of arrow B. According to FIG. 4 b , at a later point in time t 2 , the fiber bat  37  has been advanced in the direction of arrows C, D and E. It is essential that the conveying surface, i.e., the outer shell surface  26 ″ of rotating cylinder  26 , the fiber bat  37 , and the needles  30  have the same speed in the conveying direction during the needle treatment, from the start of penetration of the needles  30  into the fiber bat, through full penetration and complete withdrawal of the needles. The needle rows  30   1  through  30   4  in FIG. 4 b  are in a different position than in FIG. 4 a . According to FIG. 4 c , the rotating cylinder  26  at an even later point in time t 3  has performed nearly a three-quarters rotation with respect to its position in FIG. 4 a . The needle rows  30   1  and  30   2  are being withdrawn from fiber bat  37  in the direction of arrow B while the needle rows  30   3  and  30   4  are moving in the direction of arrow A towards the fiber bat  37 . While the rotating cylinder  26  rotates, the needles  30  perform two movements simultaneously: they perform a back and forth movement in the direction of arrows A and B while moving along a circular path shown by arrow  26 ′. 
     FIGS. 3 a  and  3   b  show an embodiment in which all movements of the conveying device, e.g., the rotational movement of the rotating cylinder  26  and the linear movements of the needles  30 , are mechanically derived from a single drive motor. 
     An endless perforated belt  38  which serves as a stitch bed circulates around three deflection rollers  39   a ,  39   b , and  39   c , as shown in FIG.  5 . The rotational direction of the deflection rollers  39   a ,  39   b , and  39   c  is indicated with the curved arrows  39 ′,  39 ″ and  39 ′″. The fiber bat  37  (not shown in FIG. 5) is guided and conveyed between the curved outside  38 ′ of the perforated belt  38  and the outer shell surface  26 ″ of rotating cylinder  26  which rotates in the direction shown by arrow  26 ′. It is essential that the perforated belt  38 , the outside  38 ′ of which forms another conveying surface, the outer shell surface  26 ″ of rotating cylinder  26 , the fiber bat, and the needles (not shown in FIG. 5) have the same speed in the conveying direction shown by arrow E during the needle-treatment. The belt forms part of the entire conveying device. 
     FIG. 6 a  shows the deflection of the perforated belt  38  with openings  40  around a belt deflection device (not shown in FIG. 6 a ). Successive recesses  41  which penetrate through perforated belt  38  are provided in one edge region (as shown) or in both edge regions of perforated belt  38 . The edges bounding the recesses in the conveying direction of perforated belt  38  are reinforced with edge-reinforcing elements  42   a  and  42   b  against wear and tear. The edge-reinforcing elements  42   a  and  42   b  have rounded outer surfaces. As shown in FIG. 6 b , the teeth  43   a  of a toothed wheel  43  extend through the recesses of the perforated belt  38 . The toothed wheel is driven (in a manner not shown herein) by a device, e.g., a drive motor, in the direction of the curved arrow  43 ′. 
     In another embodiment of the stitch bed shown in FIG. 7, the circulating endless perforated belt is an endless ladder belt formed by two endless toothed belts, only one belt  44   a  being shown herein. A plurality of strips  45  span between the outside of the endless toothed belts. The strips  45  have openings  46  through which the needles (not shown in FIG. 7) can penetrate. Gearwheels (not shown in FIG. 7) are used to drive the toothed belts. 
     In yet another embodiment (not shown herein), the stitch bed is formed of a mesh material. 
     Belts which serve as stitch beds can be formed of any one of a number of materials, including steel. 
     FIG. 8 a  shows a needle-treatment system composed of a plurality of conveying devices  15   a  through  15   f  according to the invention that are serially connected. The drive motors and drive mechanisms for moving the needles for the conveying devices  15   a  through  15   f  are connected to a common electronic control  51 , shown in FIG. 8 b , for coordinating the conveying and needle speeds of the conveying devices relative to each other; the conveying speeds and the needle speeds of any two of the conveying devices in the needle treatment system can be identical or different. 
     In the embodiment of the conveying device shown in FIGS. 9 a  and  9   b , a drive motor  91  drives the rotational movement of the rotating cylinder  26  and separate drive mechanisms  92  for moving the needles drive the linear movements of the needles  30 . 
     In an embodiment, shown in FIG. 10, the drive motor  91  for the rotating cylinder, the drive motor or motors  101  for a circulating endless belt, and the drive mechanism or mechanisms  92  for moving the needles can be connected to a common electronic control  102 . The common electronic control  102  coordinates the drive motors  91  and  101  and drive mechanisms  92  for moving the needles to ensure that the rotating cylinder, needles, fiber bat, and circulating endless belt all travel with the same speed in the conveying direction. The common electronic control  102  controls the points in time of insertion and of removal of the needles. 
     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, and the invention, therefore, as defined in the appended claims, is intended to cover all such changes and modifications that fall within the true spirit of the invention.