Patent Publication Number: US-2006009340-A1

Title: Adjustable bias folder

Description:
BACKGROUND OF THE INVENTION  
      The present invention relates to a bias folder. More particularly, this invention relates to an adjustable bias folder that can produce various kinds of bias tapes with a single bias folder.  
       FIG. 5  shows a bias folder  10  by prior art. The bias folder  10  produces a bias tape of fixed type and dimension. A bias tape may be single-folded or double-folded, and folded portions of a bias tape may have different sizes depending on the use of a bias tape produced by the bias folder. A set of many number of bias folders have been required and to be replaced to produce different kinds of bias tapes.  
      A simpler or more efficient device for producing bias tapes has long been in need.  
     SUMMARY OF THE INVENTION  
      The present invention contrives to solve the need that was not satisfied by the prior art.  
      An objective of the invention is to provide an adjustable bias folder that can produce a single-folded bias tape or a double-folded bias tape selectively without changing the bias folder.  
      Another objective of the invention is to provide a bias folder that can produce bias tapes having different dimensions without changing the bias folder.  
      To accomplish the above objectives, the present invention provides an adjustable bias folder that includes a fabric path through which a fabric strip passes and an adjusting device. The fabric path includes a first end and a second end. The fabric strip enters the fabric path at the first end. The fabric strip is folded to have one or more folded portions at the second end as the fabric strip exits the fabric path. The adjusting device adjusts the dimension of the folded portions.  
      The adjusting device includes a first adjuster that adjusts the dimension of one of the folded portions of the fabric strip, and a second adjuster that adjusts the dimension of another one of the folded portions of the fabric strip.  
      The first adjuster is movable between a first retracted position and a first extended position. The first adjuster is nearest to the second end of the fabric path in the first retracted position and farthest to the second end of the fabric path in the first extended position.  
      Similarly, the second adjuster is movable between a second retracted position and a second extended position. The second adjuster is nearest to the second end of the fabric path in the second retracted position and farthest to the second end of the fabric path in the second extended position.  
      The fabric path further includes a curved portion on which the fabric strip slides. The curved portion gradually becomes narrower from the first end to the second end.  
      The fabric path further includes a first recess that is positioned on one side of the curved portion and a first flange that is positioned in the first recess. The first recess and the first flange guides the fabric strip so that one of the folded portions of the fabric strip is formed. The fabric path further includes a second recess that is positioned on the other side of the curved portion and a second flange that is positioned in the second recess. The second recess and the second flange guides the fabric strip so that another one of the folded portions of the fabric strip is formed.  
      The first adjuster includes a first elongated plate, and a first extension. The first elongated plate includes a first plate end and a second plate end. The first extension extends from the first plate end of the first elongated plate. The first extension makes an angle with the first elongated plate. The second adjuster includes a second elongated plate, and a second extension. The second elongated plate includes a first plate end and a second plate end. The second extension extends from the second plate end of the second elongated plate. The second extension makes an angle with the second elongated plate.  
      The first elongated plate slides under the first recess. The first extension abuts with the second end of the fabric path when the first adjuster is in the first retracted position. The second elongated plate slides under the second recess. The second extension abuts with the second end of the fabric path when the second adjuster is in the second retracted position.  
      The second plate end of the first elongated plate is connected to an adjusting lever so that movement of the adjusting lever moves the first adjuster between the first retracted position and the first extended position. The second plate end of the second elongated plate is connected to the adjusting lever so that movement of the adjusting lever moves the second adjuster between the second retracted position and the second extended position.  
      The adjusting lever pivots with respect to a first point. The first adjuster is connected to the adjusting lever at a second point. The second adjuster is connected to the adjusting lever at a third point. The second point and the third point are oppositely positioned with respect to the first point.  
      The first extension is substantially perpendicular to the first elongated plate. The second extension is substantially perpendicular to the second elongated plate.  
      The adjustable bias folder further includes a bracket attached to the fabric path. The bracket guides the fabric strip near the second end of the fabric path.  
      The adjustable bias folder further includes a straightener attached to the fabric path. The straightener keeps the fabric strip in substantially the same plane with the fabric path.  
      An adjustable bias folder having a single adjuster that adjusts the dimension of a single folded portion of the fabric strip is also provided by the present invention.  
      The advantages of the present invention are: (1) a single bias folder can be used to produce a single-folded bias tape or a double-folded bias tape selectively without changing the bias folder; (2) a single bias folder can be used to produce bias tapes having folded portions of different dimensions; (3) the dimensions of the folded portions can be easily adjusted with simple operation.  
      Although the present invention is briefly summarized, the fuller understanding of the invention can be obtained by the following drawings, detailed description and appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      These and other features, aspects and advantages of the present invention will become better understood with reference to the accompanying drawings, wherein:  
       FIG. 1  is a cross-sectional view showing a single folded bias tape;  
       FIG. 2  is a cross-sectional view showing a double folded bias tape;  
       FIG. 3  is a view similar to  FIG. 1  but showing a folded portion having a different size;  
       FIG. 4  is a view similar to  FIG. 2  but showing folded portions having different sizes;  
       FIG. 5  is an illustrative perspective view showing a bias folder by prior art;  
       FIG. 6  is an illustrative perspective view showing an adjustable bias folder according to the present invention;  
       FIG. 7  is a partial plan view of the adjustable bias folder;  
       FIG. 8  is a partial elevation view of the adjustable bias folder;  
       FIG. 9  is a partial bottom view of the adjustable bias folder;  
       FIG. 10  is a cross-sectional view taken along the line X-X in  FIG. 7 ;  
       FIG. 11  is a cross-sectional view taken along the line XI-XI in  FIG. 7 ;  
       FIG. 12  is a schematic plan view showing a first adjuster is in its extended position, and a second adjuster is in its retraced position;  
       FIG. 13  is a schematic plan view showing the first adjuster is in its retracted position, and the second adjuster is in its extended position; and  
       FIG. 14  is schematic plan view showing the first adjuster and the second adjuster are in their intermediate position. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       FIGS. 1-4  show various examples of bias tapes in cross-section.  FIG. 1  shows a single folded bias tape  12 .  FIG. 3  shows another single folded bias tape  14  having a folded portion  16  of a different size.  FIG. 2  shows a double folded bias tape  18 .  FIG. 4  shows another double folded bias tape  20  having folded portions  22 ,  24  having different sizes.  
       FIG. 6  shows an adjustable bias folder  26  according to the present invention. The adjustable bias folder  26  includes a fabric path  28  through which a fabric strip  30  passes and an adjusting device  32 .  
      The fabric path  28  includes a first end  34  and a second end  36 . The fabric strip  30  enters the fabric path  28  at the first end  34 . The fabric strip  30  is folded to have one or more folded portions  16 ,  22  at the second end  36  as the fabric strip  30  exits the fabric path  28 . The adjusting device  32  adjusts the dimension of the folded portions  16 ,  22 .  
      As shown in  FIGS. 7-9 , the adjusting device  32  includes a first adjuster  38  that adjusts the dimension of one of the folded portions  16 ,  22  of the fabric strip  30 , and a second adjuster  40  that adjusts the dimension of another one of the folded portions of the fabric strip  30 .  
      The first adjuster  38  is movable between a first retracted position and a first extended position. The first adjuster  38  is nearest to the second end  36  of the fabric path  28  in the first retracted position and farthest to the second end  36  of the fabric path  28  in the first extended position.  
      Similarly, the second adjuster  40  is movable between a second retracted position and a second extended position. The second adjuster  40  is nearest to the second end  36  of the fabric path  28  in the second retracted position and farthest to the second end  36  of the fabric path  28  in the second extended position.  FIGS. 12-14  show variations of the positions of the first adjuster  38  and the second adjuster  40 .  
      As shown in  FIGS. 10 and 11 , the fabric path  28  further includes a curved portion  42  on which the fabric strip  30  slides. The curved portion  42  gradually becomes narrower from the first end  34  to the second end  36 .  
      The fabric path  28  further includes a first recess  44  that is positioned on one side of the curved portion  42  and a first flange  46  that is positioned in the first recess  44 . The first recess  44  and the first flange  46  guides the fabric strip  30  so that one of the folded portions  16 ,  22 ,  24  of the fabric strip  30  is formed.  
      The fabric path  28  further includes a second recess  48  that is positioned on the other side of the curved portion  42  and a second flange  50  that is positioned in the second recess  48 . The second recess  48  and the second flange  50  guides the fabric strip  30  so that another one of the folded portions  16 ,  22 ,  24  of the fabric strip  30  is formed.  
      The first adjuster  38  includes a first elongated plate  52 , and a first extension  54 . The first elongated plate  52  includes a first plate end  56  and a second plate end  58 . The first extension  54  extends from the first plate end  56  of the first elongated plate  52 . The first extension  54  makes an angle with the first elongated plate  52 .  
      The second adjuster  40  includes a second elongated plate  60 , and a second extension  62 . The second elongated plate  60  includes a first plate end  64  and a second plate end  66 . The second extension  62  extends from the second plate end  66  of the second elongated plate  60 . The second extension  62  makes an angle with the second elongated plate  60 .  
      The first elongated plate  52  slides under the first recess  44 . The first extension  54  abuts with the second end  36  of the fabric path  28  when the first adjuster  38  is in the first retracted position as shown in  FIG. 13 .  
      The second elongated plate  60  slides under the second recess  48 . The second extension  62  abuts with the second end  36  of the fabric path  28  when the second adjuster  40  is in the second retracted position as shown in  FIG. 12 .  
      Referring back to  FIG. 9 , the second plate end  58  of the first elongated plate  52  is connected to an adjusting lever  68  so that movement of the adjusting lever  68  moves the first adjuster  38  between the first retracted position and the first extended position.  
      The second plate end  66  of the second elongated plate  60  is connected to the adjusting lever  68  so that movement of the adjusting lever  68  moves the second adjuster  40  between the second retracted position and the second extended position.  
      The adjusting lever  68  is pivotally attached to the fabric path  28 . The adjusting lever  68  pivots with respect to a first point  70 . The first adjuster  38  is connected to the adjusting lever  68  at a second point  72 . The second adjuster  40  is connected to the adjusting lever  68  at a third point  74 . The second point  72  and the third point  74  are oppositely positioned with respect to the first point  70  so that the first adjuster  38  and the second adjuster  40  are moved oppositely with each other by pivoting the adjusting lever  68 .  
      The first extension  54  is substantially perpendicular to the first elongated plate  52 . The second extension  62  is substantially perpendicular to the second elongated plate  60 .  
      Referring back to  FIG. 6 , the adjustable bias folder  26  further includes a bracket  76  attached to the fabric path  28 . The bracket  76  guides the fabric strip  30  near the second end  36  of the fabric path  28 .  
      The adjustable bias folder  26  further includes a straightener  78  attached to the fabric path  28 . The straightener  78  keeps the fabric strip  30  in substantially the same plane with the fabric path  28 .  
      An adjustable bias folder having a single adjuster that adjusts the dimension of a single folded portion of the fabric strip is also possible.  
      While the invention has been shown and described with reference to different embodiments thereof, it will be appreciated by those skilled in the art that variations in form, detail, compositions and operation may be made without departing from the spirit and scope of the invention as defined by the accompanying claims.