Patent Publication Number: US-9844289-B2

Title: Ribbon-type device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     Benefit is claimed of U.S. patent application Ser. No. 61/693,863, filed Aug. 28, 2012, and entitled “Ribbon-Type Device”, the disclosure of which is incorporated by reference herein in its entirety as if set forth at length. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates to a ribbon-type device for effecting undulation in the form of an accommodation means for a pull cord of a curtain for gathering the same in the vertical or horizontal direction. 
     Ribbon-type devices for effecting undulation of the above type are known in the prior art in a number of various embodiments. The known devices, however, suffer from the serious drawback that the pull cord or other cords can form large loops in which body parts, in particular, such as a finger, an arm or even the head of a child can become entangled, and this has resulted in considerable injuries in the past. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide a ribbon-type device for effecting undulation in the form of an accommodation means for a pull cord of a curtain, which device safeguards against injuries and, at the same time, enables the curtain to be gathered rapidly and effectively. 
     For a ribbon-type device for effecting undulation of the above type, this object is achieved, according to the invention, in that there is provided a functional unit comprising two tapes of fabric, each of which extends in an undulating manner to form a plurality of alternating positively and negatively curved arcs, an arc of positive curvature of the first fabric tape being set so as to oppose an arc of negative curvature of the second fabric tape and an arc of negative curvature of the first fabric tape being set so as to oppose an arc of positive curvature of the second fabric tape, the two fabric tapes being joined to each other at each transition between an arc of positive curvature and an arc of negative curvature by means of tie-off stitching, the plurality of such tie-offs forming accommodation means for a pull cord of a curtain. 
     Preferred embodiments of the invention are the subject matter of the sub claims. 
     By means of the above combination of features in the ribbon-type device for effecting undulation according to the invention, the alternating arcs of the functional contracting and expanding unit act as backing elements for a pull cord, and it is possible to keep the arcs so small by virtue of their design that parts of the human body, including those of children, cannot get caught up between the arcs. Furthermore, the contracting and expanding unit of the invention forms a safe accommodation means for a pull cord so that the possibility of the pull cord forming artificial loops is highly improbable. 
     According to a first preferred embodiment of the device of the invention, the tie-offs are spaced from each other at equal intervals. Preferably, the distance between any two adjacent tie-offs ranges from 0.5 cm to 2 cm. 
     According to an important preferred embodiment of the device of the invention, the warp threads of each fabric tape cross each other in the region of the tie-off stitching, and the two tapes of fabric are securely joined to each other by interweaving of the weft threads of each fabric tape. Preferably, the two fabric tapes of the functional unit are each made of soft multifilament yarns. 
     According to a further preferred embodiment of the device of the invention, the functional unit comprising the two tapes of fabric is attached to a tape of backing fabric that has a larger width than the two tapes of fabric and that is intended for application of the functional unit to a curtain. 
     Preferably, the backing fabric is made of robust monofilaments, the diameter of which is larger than that of the multifilament yarns in the fabric tapes of the functional unit. 
     According to another preferred embodiment of the device of the invention, the functional unit is attached to the backing fabric by interweaving the arcs of negative curvature of any one of the two tapes of fabric with the backing fabric. Preferably, the other of the two fabric tapes of the functional unit is not interwoven with the backing fabric so that an isolated arc of negative curvature is formed. 
     The functional unit of said two fabrics is preferably attached to a tape of backing fabric so as to form a plurality of isolated arcs. The length of an arc can be variably predefined for different curtains, in order to predefine the folds formed in a curtain. 
     The curtain is preferably attached to the tape of backing fabric. Therein, the curtain is preferably attached to the tape of backing fabric in that the curtain is sewn to the backing fabric by means of two seams running parallel to said pull cord. Preferably, the seams do not include said two fabrics. 
     The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The device of the invention is explained below with reference to a preferred embodiment illustrated in the figure of the drawings. In the drawings: 
         FIG. 1  shows a preferred embodiment of the ribbon-type device for effecting undulation according to the invention in a view taken obliquely from above. 
         FIG. 2  is a detail of the preferred embodiment of the ribbon-type device shown in  FIG. 1 . 
         FIG. 3  is a view taken obliquely from above of the ribbon-type device shown in  FIG. 1  together with an non-gathered curtain. 
         FIG. 4  is a view taken obliquely from above of the ribbon-type device shown in  FIG. 1  together with an gathered curtain. 
     
    
    
     Like reference numbers and designations in the various drawings indicate like elements. 
     DETAILED DESCRIPTION 
     The ribbon-type device  100  for effecting undulation according to the invention as shown in  FIG. 1  represents an accommodation means for a pull cord  140  of a curtain for gathering the same in the vertical or horizontal direction and comprises a functional unit  160  comprising two tapes of fabric  110 ,  120 . 
     Each of the two fabric tapes  110 ,  120  extends in an undulating manner to form a plurality of alternating positively and negatively curved arcs  111 ,  121 ,  112 ,  122 , an arc of positive curvature  111  of the first fabric tape  110  being set so as to oppose an arc of negative curvature  122  of the second fabric tape  120  and an arc of negative curvature  112  of the first fabric tape  110  being set so as to oppose an arc of positive curvature  121  of the second fabric tape  120 . 
     Furthermore, the two fabric tapes  110 ,  120  are joined to each other at each transition between an arc of positive curvature  111 ,  121  and an arc of negative curvature  112 ,  122  by way of tie-off stitching  130 , the plurality of such tie-offs  130  forming an accommodation means for a pull cord  140  of a curtain. The tie-offs  130  are spaced from each other at equal intervals of approximately 1 cm. 
     The warp threads of each fabric tape  110 ,  120  cross each other in the region of the tie-off stitching  130 , and the two tapes of fabric  110 ,  120  are securely joined to each other by interweaving of the weft threads of each fabric tape. The two fabric tapes  110 ,  120  of the functional unit  160  are each made of soft multifilament yarns. 
     The functional unit  160  comprising the two tapes of fabric  110 ,  120  is attached to a tape of backing fabric  170  that has a larger width than the two tapes of fabric  110 ,  120  and that is intended for application of the functional unit  160  to a curtain. The backing fabric  170  comprises robust monofilaments, the diameter of which is larger than that of the multifilament yarns in the fabric tapes  110 ,  120  of the functional unit  160 . 
     The functional unit  160  is attached to the backing fabric  170  by interweaving of the arcs of negative curvature  112 ,  122  of any one of the two tapes of fabric  110 ,  120  with the backing fabric  170 , whilst the other of the two fabric tapes  110 ,  120  of the functional unit  160  is not interwoven with the backing fabric  170 , so that an isolated arc of negative curvature  112 ,  122  is formed. 
     The functional unit ( 160 ) of said two fabrics ( 110 ,  120 ) is attached to a tape of backing fabric ( 170 ) so as to form a plurality of isolated arcs. The length of an arc can be variably predefined for different curtains, in order to predefine the folds formed in a curtain. 
     The curtain material  180  is attached to each tape of backing fabric ( 170 ). The curtain material is attached to the tape of backing fabric ( 170 ) in that the curtain material is sewn to the backing fabric ( 170 ) by means of two seams  190 A,  190 B running parallel to said pull cord. The seams do not include said two fabrics ( 110 ,  120 ). 
     The exemplary embodiment of the invention explained above merely serves the purpose of providing better comprehension of the teaching of the invention defined in the claims, which teaching is not, as such, restricted to the exemplary embodiment.