Patent Publication Number: US-6659138-B2

Title: Device for producing a tape having a curve, especially a curved flat line compound

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to an apparatus for producing a band having a curve, especially, a curved flat composite cable, the apparatus being comprised of several clamping jaw pairs arranged downstream of a weaving device for withdrawing the individual lines which form the composite cable. 
     DE 198 16 666 A1 discloses the production of a band as woven composites with a curve in the plane of the weave. In this reference, an apparatus is also disclosed for the production of curved bands. The disclosed apparatus comprises a weft intake location of a narrow materials loom to which a gripper mechanism for clamping the warp threads with two gripping clamps is arranged. A clamping jaw pair, hereinafter referred to as grip clamps, is moveable and its jaws are driven and the other clamping jaw pair is fixed. 
     In order to weave a curve, the moveable grip clamps are closed to thereby clamp the warp threads, while the fixed grip clamps are opened. Then, the moveable grip clamps are moved about a rotation point, which leads to the result that the warp threads of the woven composite are moved during each cycle by an amount which increases from an angle which is nearer to the rotation point toward an angle of the grip clamps which is further from the rotation point. A curve is produced in the woven composite on the side toward the warp threads which are withdrawn by the relatively shorter amount. At the end of the movement, the fixed grip clamps are closed and the moveable grip clamps are opened and these moveable grip clamps return in a direction in opposition to the withdrawal direction back to their start position. 
     The course of movement is periodic. A curve is produced whose radius is given by the distance of the rotation point from the warp threads and whose sense of direction or handedness is given by the position to the right or the left of the warp threads relative to the position of the rotation point. To produce straight pieces, the moveable grip clamps are moved in a straight line manner. 
     The disadvantage of this apparatus is that the withdrawal process proceeds in a start-stop manner, in that, in connection with the movement of the moveable grip clamps back toward their start position, the transport of the warp threads must be abruptly interrupted. Particularly in connection with the working of warp threads of substantial mass, such as insulating electrical lines in comparison to pure textile yarns, strong fluctuations occur in the material which may be propagated up to the line building mechanism in the weaving machine or loom and, in connection with an increasing weft count, the production of a composite without problems or disturbances is increasingly impacted and is even fully impossible. Moreover, the apparatus permits only a very limited variation of the radii of the curves. 
     The present invention provides a solution to the challenge of providing a substantially uniform movement of the warp threads. 
     SUMMARY OF THE INVENTION 
     In accordance with the invention, this challenge is met in that all of the clamping jaw pairs are moveable relatively along the withdrawal direction and are driven and are pivoted. 
     In a preferred embodiment of the present invention, two clamping jaw pairs are arranged which are moveable back and forth along the extent of the withdrawal direction in alternating manner by means of a drive mechanism which engages the ends of the clamping jaws, whereby the amplitude of movement of both sides is independently variable. 
     The drive mechanism can preferably be comprised of a crank drive system, whereby, on each side of each clamping jaw, a crank drive engages and the stroke of the crank drive of one side relative to the stroke of the crank drive of the other side is adjustably variable. 
     In a further preferred embodiment of the present invention, a plurality of clamping jaws are arranged on one or more pairs of driven, endlessly circulating, non-rotatable drive means such that the clamping jaws are arranged in opposing manner by pairs. The clamping jaws comprise start cranks with sloping crank or start surfaces. Start rollers are provided adjacent the drive mechanism which are swingable into the path of movement of the start cranks. Elastic return movement elements, especially, spiral springs or flat springs, are preferably arranged between adjacent clamping jaws. 
     The drive mechanism, which is not extendable, comprises, preferably, roller chains or toothed drive chains. With the deployment of the inventive device, it is possible to use as warp thread differing material in order to meet the most stringent demands of the warp thread customer. 
     The warp threads are, for example, insulating copper lines, hoses for the conveyance of media and for pneumatic and hydraulic arrangements, armored or reinforced cords or yarns of cord, steel, carbon, or the like, light conducting cables, and similar materials. 
     The radii of the curves can be adjusted within a wide range which is not dependent upon the width of the clamping jaws. It is possible, for example, in correspondence with the demands of the aircraft and commercial vehicle industries, to finish or produce flat cables. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention is described with the aid of the hereinafter following exemplary embodiment in more detail. In the accompanying drawings, it is shown: 
     FIG. 1 is a side view of one embodiment of the device of the present invention with a crank drive, 
     FIG. 2 is a plan view of the device shown in FIG. 1, 
     FIG. 3 is a view of the working principle of the withdrawal device shown in FIG. 1, 
     FIG. 4 is a view of the lower portion of a withdrawal device having a chain drive, 
     FIG. 5 is a side view of the withdrawal device shown in FIG. 4, and 
     FIG. 6 is a view of the swing movement of the clamping jaws of a withdrawal device having a chain drive. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIG. 1 shows a side view of a device in accordance with the present invention in combination with a narrow materials loom. The device comprises four clamping jaws  1 ,  2 ,  3 ,  4  of which respective ones are respectively paired with one another to thereby form two respective pairs of clamping jaws. Individual lines  5  extend between each respective pair of clamping jaws, the individual lines being the warp threads of a composite cable. Each clamping jaw is travels along a broken line-depicted path  6 . A linkage rod  7 ,  7 ′,  8 ,  8 ′,  9 ,  9 ′,  10 ,  10 ′ engages the end of each clamping jaw to thereby couple the clamping jaw to a crank  11 ,  11 ′,  12 ,  12 ′,  13 ,  13 ′,  14 , and  14 ′ (FIG.  1  and FIG.  2 ). The linkage rods  8 ′ and  10 ′ as well as the cranks  12 ′ and  14 ′ are not shown. The cranks of the upper clamping jaws  1 ,  3  are driven via the upper shaft  15  and the cranks of the lower clamping jaws are driven via the lower shaft  16 . An offset of 180° is present between the cranks  11 ,  11 ′,  12 ,  12 ′ for the front clamping jaws  1  and  2  and the cranks  13 ,  13 ′,  14 , and  14  for the back clamping jaws. A weft infeed  17  (compare FIG. 2) is disposed in front of the front clamping jaws  1 ,  2 . 
     The device operates as follows: 
     The upper shaft  16  is rotated in a clockwise direction and the lower shaft  16  is rotated in the counter clockwise direction. Due to this rotational movement, the pair of the front clamping jaws  1 ,  2  and the back clamping jaws  3 ,  4  move along the path  6  in alternating manner back and forth. 
     If a clamping jaw pair reaches the front dead point (adjacent the weft in-feed), the clamping jaw pair closes and engages the individual lines  5 . At that instant, the other clamping jaw pair reaches the back dead point and opens. This operational condition is shown in FIG.  1 . The arrows show the path of movement. The back clamping jaws  3 , 4  are located shortly before the back dead point and are in engagement with the individual lines  5 , while the front clamping jaws  1 , 2  are located shortly before the front dead point and are open. 
     A curve is produced if the amplitude of movement of the linkage rods (the stroke) on one side of the clamping jaw pairs  1 ,  2 ,  3 ,  4  is different relative to that of the other side. FIG. 3 shows this operational condition. In this figure, for the purpose of providing a clearer overview, only the portion above the individual lines  5  is shown. The portion under the individual lines operate synchronously. 
     As seen in FIG. 3, the linkage rods  7 ,  9  have, as a result of a shorter adjusted crank  11 ,  13 , a relatively smaller amplitude than the right linkage rods  7 ′,  9 ′ which are associated with the longer adjusted cranks  11 ′,  13 ′. The start position of each clamping jaw pair is shown and (shown with a fine line) the end position of each clamping jaw pair within a half period of 0 to π. 
     The right individual lines are drawn off at a relatively greater length than the left individual lines. As a function of the size of the amplitude difference, there occurs a certain curve due to the size of the difference in the curve radius. During each period, the composite cable is curved through an angle ω. The direction or handedness of curvature is determined by the side on which the amplitude in comparison to the opposed side has a smaller value. 
     The drive mechanism and the clamp mechanism are configured such that the curved composite cable can travel sideways in a problem-free manner. To improve the intake of the withdrawal force on the individual lines, the clamping jaws can be configured with a profile corresponding to the circumferential profile of the individual lines. 
     FIG. 4 shows the lower portion of a withdrawal device having a roller chain drive. This roller chain drive comprises a lower chain  18 . The clamping jaws  19  are mounted at uniform spacings from one another in pivoting manner to the lower chain  18 . The clamping jaws  19  are connected to one another via spiral springs  20  and are supported against a press band  21 . In addition to the clamping jaws, start cranks  22 ,  22 ′ are provided. The start cranks have a sloped and bent start surface. Start rollers  23  are provided on the right and left for movement in a swinging manner into the movement path of the start cranks. The individual lines  5  (FIG. 5) travel over the lower portion of the withdrawal device. 
     In FIG. 5, there is shown a mirror image view of the upper portion of the withdrawal device. The upper chain  24  can be seen with the upper clamping jaws  25  which are supported against the upper press band  26 . The lower clamping jaws  19  and the upper clamping jaws  25  are arranged in opposing manner to one another on the chains. 
     The chains travel in an endless loop in the withdrawal direction. They apply the linear withdrawal force on the individual lines. The fixing of the beginning of clamping occurs through the two press bands  21 ,  26  on the clamping jaws  19 ,  25 . The clamping jaws are arranged, such as shown in FIG. 5, on the clamping line  27  such that the individual lines are clamped at the clamping line  27  between the upper clamping jaws  19  and the synchronously traveling lower clamping jaws at  25 . 
     FIG. 6 shows the pivot of the clamping jaws. Also here, for the purpose of a clearer overview, only a portion of the lower portion of the drive mechanism is shown. The upper portion of the drive mechanism executes the same movement in a synchronous manner. The clamping jaws  19 ,  25  engage the individual lines  5  initially parallel to the weft feed intake at the clamping line. Immediately after the clamping, a clamping jaw extends with the right start crank  22 ′ against the right start roller. In conjunction with a further movement of the chain, the clamping jaw is forced into a pivot movement and, indeed, is pivoted to such an extent that it eventually slides by the start roller. The position of a clamping jaw is shown during the pivoting and fully pivoted out with cross-hatching. 
     Due to the coupling between the clamping jaws by means of the spiral springs  20 , those clamping jaws, which lie in the travel direction of the chain ahead of the engaged clamping jaw, are also moved as well. Optionally, deployable additional start rollers can be provided as well for this purpose. In this manner, it is achieved that the tension in the material can be maintained for a longer duration than only during the time at which it passes the clamping line. 
     The thus-produced pivoting of the clamping jaws  19 ,  25  around the start crank  22 ′ effects different withdrawal of the materials along the width of all of the individual lines  5  and thus ensures the creation of a curve. 
     Different clamping jaw configurations and thereby different curve radii can be achieved through more or less strong backward movement of the start rollers, as is schematically shown in FIG.  6 . 
     Different senses of directions or handedness occur through the pivoting of the start roller  23  to the opposed side during simultaneous pivoting of the respective opposed start roller. 
     The clamping is released at a pre-determined distance from the clamp line selected with respect to the length of the press bands  21 ,  26 , in that the press bands end or bend away. The clamping jaws are then returned to their start positions by the spiral springs  20 . 
     The specification incorporates by reference the disclosure of German priority documents 100 01 333.3 filed Jan. 11, 2000 and PCT/DE01/00230 filed Jan. 11, 2001. 
     The present invention is, of course, in no way restricted to the specific disclosure of the specification and drawings, but also encompasses any modifications within the scope of the appended claims. 
     
       
         
           
               
             
               
                   
               
               
                 Overview of Reference Numbers 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
            
               
                   
                  1 
                 upper front clamping jaw 
               
               
                   
                  2 
                 lower front clamping jaw 
               
               
                   
                  3 
                 upper back clamping jaw 
               
               
                   
                  4 
                 lower back clamping jaw 
               
               
                   
                  5 
                 individual lines 
               
               
                   
                  6 
                 paths 
               
               
                   
                  7 
                 linkage rod 
               
               
                   
                  7′ 
                 linkage rod 
               
               
                   
                  8 
                 linkage rod 
               
               
                   
                  8′ 
                 linkage rod 
               
               
                   
                  9 
                 linkage rod 
               
               
                   
                  9′ 
                 linkage rod 
               
               
                   
                 10 
                 linkage rod 
               
               
                   
                 10′ 
                 linkage rod 
               
               
                   
                 11 
                 crank 
               
               
                   
                 11′ 
                 crank 
               
               
                   
                 12 
                 crank 
               
               
                   
                 12′ 
                 crank 
               
               
                   
                 13 
                 crank 
               
               
                   
                 13′ 
                 crank 
               
               
                   
                 14 
                 crank 
               
               
                   
                 14′ 
                 crank 
               
               
                   
                 15 
                 upper shaft 
               
               
                   
                 16 
                 lower shaft 
               
               
                   
                 17 
                 weft infeed 
               
               
                   
                 18 
                 lower chain 
               
               
                   
                 19 
                 upper clamping jaws 
               
               
                   
                 20 
                 spiral spring 
               
               
                   
                 21 
                 lower press band 
               
               
                   
                 22 
                 start cams 
               
               
                   
                 22′ 
                 start cams 
               
               
                   
                 23 
                 start roller 
               
               
                   
                 24 
                 upper chain 
               
               
                   
                 25 
                 upper clamping jaws 
               
               
                   
                 26 
                 upper press band 
               
               
                   
                 27 
                 clamping line