Patent Publication Number: US-2007119358-A1

Title: Decorative stitch

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a decorative stitch intended to provide a fabric with decorativeness at the top surface.  
      2. Explanation of the Related Art  
      A conventional decorative stitch is disclosed, for example, as “Stitch type 602” in JIS L 0120-1984 (Federal Standard No. 751a), which is composed of a plurality of needle threads and one cover thread.  
      In the conventional decorative stitch, however, since needle threads are disposed at specified interval at the top surface of fabric and are passed through loops of cover thread already cast on the top surface of fabric, the cover loops of the cover thread are very obvious visually, and the entire stitch looks very heavy.  
     SUMMARY OF THE INVENTION  
      It is hence an object of the present invention to provide a decorative stitch not spoiling the decorativeness while tightening the cover loops of cover thread compactly if needle threads are disposed at specified interval at the top surface of fabric.  
      The decorative stitch of the present invention includes a plurality of needle threads having needle thread loops disposed at specified interval at the top surface of fabric and passed through cover loops of cover thread already cast on the top surface of fabric.  
      A feature of the decorative stitch is that upper ends of needle thread loops are collected at the top surface of fabric by cover thread loops so as to adjacent each other.  
      According to the present invention, since the upper ends of needle thread loops are adjacent to each other, the cover loops of the cover thread are compact at the top surface of fabric, and heavy image can be eliminated.  
      In the decorative stitch of the present invention, said upper ends are aligned at the upper ends of the rightmost needle thread loop or the leftmost needle thread loop. Then, it is not required to set strictly the tension balance of needle threads when forming the stitch.  
      When the rightmost end of the upper ends of needle thread loops is shifted from the upper end of other needle thread loops, the cover thread can be applied smoothly. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
       FIG. 1  is a perspective view of first embodiment of decorative stitch according to the present invention.  
       FIG. 2  is a photograph showing the fabric surface side in first embodiment.  
       FIG. 3  is a photograph showing the fabric surface side of other decorative stitch.  
       FIG. 4  is a perspective view of second embodiment of decorative stitch according to the present invention.  
       FIG. 5  is a photograph showing the fabric surface side in second embodiment. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      Preferred embodiments are described by referring to the accompanying drawings. A decorative stitch S 1  is, as shown in  FIG. 1 , composed of two needle threads  1 ,  2  and one cover thread  3 . The needle threads  1 ,  2  have needle thread loops, the needle thread loops are disposed at specified interval at the top surface of fabric. The upper end  2   a  of needle thread loops of right side needle thread  2  is shifted to the upper end  1   a  of needle thread loops of left side needle thread  1 . That is, the upper ends  1   a ,  2   a  of the needle thread loops are adjacent to each other. Under loops  1 L,  2 L of needle threads are passed through two divided loops  4   a ,  4   b  of looper thread  4 , and interlooped with other one loop  4   e  of looper thread  4 . The looper thread  4  is located at the bottom surface of fabric.  
      The cover thread  3  forms right and left cover loops  3   a ,  3   b  stretched horizontally at the top surface of fabric, and the cover loops  3   a ,  3   b  cross across the upper ends  1   a ,  2   a  of needle thread loops stretched at the top surface of fabric. The under needle thread loops  1 L,  2 L are passed through the cover loops  3   a ,  3   b  of cover thread  3  already cast on the top surface of fabric. The upper end  2   a  of needle thread loop of right side needle thread is shifted to the front side by the cover thread  3 , and the top surface of fabric has a pattern as shown in  FIG. 2  (the pattern shown in the middle). As a result, casting of cover thread  3  is smooth, and the upper ends  1   a ,  2   a  of needle thread loops are collected by the loops  3   a ,  3   b  of the cover thread  3 .  
      In this preferred embodiment, the upper end of needle thread loop of right side needle thread is shifted to the left side needle thread side, but this is not limited. For example, the upper end of needle thread loop of left side needle thread maybe shifted to the right side needle thread side, or the upper ends  1   a ,  2   a  of needle thread loops may be collected in the middle as shown in  FIG. 3 . In this preferred embodiment, the decorative stitch is composed of two needle threads, but not limited to this, for example, the decorative stitch may be composed of three needle threads.  
      An example of decorative stitch S 2  composed of three needle threads is shown in  FIG. 4 . This decorative stitch S 2  comprises three needle threads  5 ,  6 ,  7  and one cover thread  8 . The needle threads  5 ,  6 ,  7  are disposed at specified interval at the top surface of fabric, and upper ends  5   a ,  7   a  of needle thread loops of needle threads at both sides are shifted to the upper end  6   a  of the middle needle thread loop. That is, the upper ends  5   a ,  6   a ,  7   a  of the needle thread loops are adjacent to each other. The cover thread  8  forms right and left cover loops  8   a ,  8   b  stretched horizontally at the top surface of fabric, and the cover loops  8   a ,  8   b  cross across the upper ends  5   a ,  6   a ,  7   a  of needle thread loops already cast on the top surface of fabric. The under loops of needle thread are passed through the cover loops  8   a ,  8   b  of cover thread  8  already cast on the top surface of fabric.  
      The upper end  5   a  of needle thread loop of left side needle thread and the upper end  6   a  of needle thread loop of middle needle thread are aligned, but the upper end  7   a  of needle thread loop of right side needle thread is shifted to the front side by the cover thread  8 , and the top surface of fabric has a pattern as shown in  FIG. 5  (the pattern shown in the middle). As a result, casting of cover thread  8  is smooth, and the upper ends  5   a ,  6   a    7   a  of needle thread loops are collected by the loops  8   a ,  8   b  of the cover thread  8 . Under loops of needle thread  5 ,  6 ,  7  are passed through three divided loops of looper thread  9 , and interlooped with other one loop of looper thread  9 .  
      The sewing machine for forming the decorative stitch of the present invention may be any known interlock sewing machine. A known interlock sewing machine generally has a tensioning device for each thread at the front side, and thread tension on thread route is changed by operation of the tensioning device. As a result, the length of each thread for forming the decorative stitch is changed. In the case of decorative stitch S 1 , the tension is slightly set lower for the right side needle thread  2 , and in the case of decorative stitch S 2 , the tension is slightly set lower for the needle threads  5 ,  7  at both sides. The tension is set slightly higher for the cover threads  3 ,  8 , and the tension should be normal for the looper threads  4 ,  9 .  
      In the preferred embodiment, only one looper thread is disposed at the bottom surface of fabric, but not limited to this, a plurality of looper threads may be provided according to the needle threads.