Patent Abstract:
A bias tape maker includes an outer shell including a tape entering port and a tape exiting port for introduction and exit of a main tape, respectively, and an inner core fitted in the outer shell for defining a main tape passage between the outer shell and the inner core. The main tape passage has a tape folding portion for folding longitudinal margins of the main tape toward each other. The outer shell is provided with an auxiliary tape entry window adjacent the tape exiting port for introducing an auxiliary tape into the tape folding portion of the main tape passage.

Full Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a device for making a bias tape which is mainly used for finishing or decorating clothing or the like. Such a device is referred to as a bias tape maker. 
     2. Description of the Related Art 
     A bias tape is a narrow strip of cloth having a pair of longitudinal margins folded toward each other. Such a bias tape may be made by cutting a cloth diagonally across the weave to provide an elongate bias cloth, and then folding the longitudinal margins of the bias cloth toward each other. The bias tape thus provided has a good stretch and a high flexibility so that it is suited for use in finishing or decorating clothes or the like. 
     FIG. 10 illustrates atypical prior art bias tape maker. The bias tape maker  100  comprises an outer shell  102  and an inner core  103  for insertion into the outer shell  102 . The outer shell  102 , which may be made by bending a thin metal plate, has a generally tubular configuration which is progressively flattened toward its front end. The outer shell  102  includes a pair of roof margins  21 . 
     The inner core  103 , which may be made of a resin, tapers from its rear end toward its front end. The inner core  103  is formed with a generally triangular platform  131  which is laterally formed with a pair of longitudinal engaging grooves  32 . 
     As shown in FIG. 11, by engaging the roof margins  21  of the outer shell  102  with the engaging grooves  3 , the outer shell  102  is assembled with the inner core  103 . In the bias tape maker  100  thus assembled, a tape folding portion (not specifically shown) is defined between the inner core  102  and the outer shell  103 . 
     In use, a bias cloth  11  is introduced into the bias tape maker  100  from the rear end thereof. In advancing through the non-illustrated tape folding portion toward the front end of the tape maker  100 , the bias cloth  11  is continuously formed into a bias tape  1  provided with a pair of longitudinally extending folds  11   a . The bias tape  1  thus formed is pulled out from the front end of the bias tape maker  100 . The folds  11   a  may then be fixed or set by ironing for example. 
     The bias tape thus provided may be fixed on clothing for example in the following manner. First, the bias tape is bent into a desired configuration and ironed for example for setting the configuration. Then, the bias tape is disposed on clothing and provisionally fixed thereon with pins or needles for example. Then, the bias tape is sewed onto the clothing. Thus, the fixing process is rather complicated and troublesome. 
     For easier fixation, a bias tape is known which is provided with an auxiliary adhesive tape. Such a bias tape is hereinafter referred to as adhesive bias tape an example of which is shown in FIG.  9 . As shown in the figure, the adhesive bias tape  1  comprises a bias cloth  11  (hereafter referred to as “main tape”) including a pair of folds  11   a , and an auxiliary tape  12  attached on the main tape  11 . The auxiliary tape  12 , which is in the form of a narrow strip, comprises an adhesive layer  12   a  which becomes tacky or sticky by heating, and a releasable substrate  12   b , such as a silicone sheet, for releasably carrying the adhesive layer  12   a.    
     For fixing the adhesive bias tape  1  onto clothing for example, the user removes the releasable substrate  12   b  from the adhesive layer  12   a . Then, while bending the bias tape  1  into a desired configuration, the user provisionally fixes the bias tape  1  onto the clothing by ironing, and then sews it onto the clothing. Thus, the adhesive bias tape  1  can be fixed more easily than an ordinary (non-adhesive) bias tape. 
     Such an adhesive bias tape  1  may be formed by disposing an auxiliary tape  12  on the folds  11   a  of a main tape  11  and then bonding the auxiliary tape  12  to the bias tape  1  by thermally melting the adhesive layer  41  by ironing for example. 
     However, such fabrication of an adhesive bias tape has the following problems. Firstly, since both the auxiliary tape  12  and the main tape  11  are in the form of a narrow strip, it is difficult to accurately position the auxiliary tape relative to the main tape. Secondly, the ironing need be performed twice, i.e., for setting the folds  11   a  of the main tape  11  and for bonding the auxiliary tape  12  to the main tape  11 , which is troublesome. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide a bias tape maker which facilitates the formation of an adhesive bias tape. 
     According to a first aspect of the present invention, a bias tape maker comprises an outer shell including a tape entering port and a tape exiting port for introduction and exit of a main tape, respectively, and an inner core fitted in the outer shell for defining a main tape passage between the outer shell and the inner core. The main tape passage includes a tape folding portion for folding longitudinal margins of the main tape toward each other. The outer shell is provided with an auxiliary tape entry window adjacent the tape exiting port for introducing an auxiliary tape into the tape folding portion of the main tape passage. 
     Preferably, the auxiliary tape entry window has a width equal to or slightly larger than that of the auxiliary tape. 
     In a preferred embodiment, the outer shell comprises a pair of roof margins which extend toward each other into abutment adjacent the tape exiting port, and the auxiliary tape entry window is defined by a cutout formed in the pair of roof margins adjacent the tape exiting port. 
     Preferably, the auxiliary tape guide groove may be aligned with the auxiliary tape entry window longitudinally of the auxiliary tape. 
     Preferably, the auxiliary tape guide groove has a width generally equal to that of the auxiliary tape. 
     Preferably, the upper portion of the inner core has a front end partially extending into the auxiliary tape entry window. 
     Preferably, the upper portion of the inner core has a rear end formed with a handle which in turn is formed with an auxiliary tape guide hole for introducing the auxiliary tape toward the auxiliary tape guide groove. 
     Preferably, the auxiliary tape guide hole may be aligned with the auxiliary tape guide groove and the auxiliary tape entry window longitudinally of the auxiliary tape. 
     Preferably, the handle is inclined backwardly upward, the auxiliary tape guide hole being provided at a base end of the handle. 
     According to a second aspect of the present invention, a bias tape maker comprises an outer shell including a tape entering port and a tape exiting port for introduction and exit of a main tape, respectively, and an inner core fitted in the outer shell for defining a main tape passage between the outer shell and the inner core. The main tape passage includes a tape folding portion for folding longitudinal margins of the main tape toward each other. The inner core includes an upper portion formed with an auxiliary tape guide groove for guiding an auxiliary tape toward the tape exiting port. 
     Other features and advantages of the present invention will become clearer from the detailed description given below with reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view showing a bias tape maker, together with a bias tape, according to an embodiment of the present invention. 
     FIG. 2 is a plan view showing an outer shell of the bias tape maker shown in FIG.  1 . 
     FIG. 3 is a side view, partially in section, showing the inner structure of the bias tape maker shown in FIG.  1 . 
     FIG. 4 is a sectional view taken along lines IV—IV in FIG.  1 . 
     FIG. 5 is a sectional view taken along lines V—V in FIG.  1 . 
     FIG. 6 is a sectional view taken along lines VI—VI in FIG.  1 . 
     FIG. 7 is a perspective view showing an inner core of the bias tape maker shown in FIG.  1 . 
     FIG. 8 is a perspective view showing the bias tape maker of FIG. 1 without a bias tape. 
     FIG. 9 is a schematic perspective view showing an adhesive bias tape which is made by the bias tape maker of the present invention. 
     FIG. 10 is an exploded perspective view showing a prior art bias tape maker. 
     FIG. 11 is a schematic perspective view showing the same prior art bias tape maker. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A preferred embodiment of the present invention will be described below in detail with reference to FIGS. 1 through 8 of the accompanying drawings. 
     Referring to FIG. 1, there is illustrated a bias tape maker A for making an adhesive bias tape  1  which includes a main tape  11  of a cloth or fabric and an auxiliary adhesive tape  12  (see also FIG.  9 ). After biasing with the bias tape maker A, the main tape  11  has a pair of longitudinal edges  11   a  folded toward each other and joined together by the auxiliary tape  12  to form a closed loop which is flattened. The auxiliary tape  12  includes an adhesive layer  12   a  carried on a releasable substrate  12   b  of a silicone paper for example. The adhesive layer  12   a  has such a nature that it becomes tacky only when heated. 
     The bias tape maker A comprises an outer shell  2 , and an inner core  3  for fitting into the outer shell  2 . The outer shell  2  may be made by cutting or punching a thin metal plate into a predetermined configuration and bending the plate. The inner core  3  may be molded of a resin. 
     As shown in FIGS. 2,  3  and  8 , the outer shell  2  includes a bottom wall  22 , a pair of sidewalls  23  rising from the bottom wall  22 , and a pair of roof margins  21  bent at the respective side walls  23  toward each other. The outer shell  2  tapers from its rear end to its front end. 
     The roof margins  21  include mutually abutting portions  21   a  near the front end of the outer shell  2  (see particularly FIG.  8 ). Thus, the outer shell  2  provides a tape exiting port  24  at its front end. Each of the roof margins  21  includes an engaging portion  21   b  for engagement with a corresponding engaging groove  32  of the inner core  3  when the inner core  3  is assembled with the outer shell  2  (see particularly FIGS.  2 - 4 ). The engaging portion  21   b  is formed with a generally triangular engaging notch  21   c  for engagement with a corresponding engaging projection (not shown) formed in the engaging groove  32 , thereby preventing the inner core  3  from being unexpectedly detached from the outer shell  2 . 
     Each of the roof margins  21  is further formed with a cutout  21   d  (FIG. 2) which defines an auxiliary tape entry window  5  adjacent the tape exiting port  24  together with the counterpart cutout  21   d  of the other roof margin  21 . The window  5  has a width W w  which is equal to or slightly larger than the width of the auxiliary tape  12 . As shown in FIG. 8, when the outer shell  2  and the inner core  3  are assembled, a front end portion  3   a  of the inner core  3  advances partially into the window  5 . However, the window  5  is still kept open for introducing the auxiliary tape  12  into the outer shell  2  adjacent the tape exiting port  24 . Alternatively, the window  5  may be defined solely by the outer shell  2  as spaced away from the front end  3   a  of the inner core  3 . 
     As shown in FIG. 2, the bottom wall  22  of the outer shell  2  is formed with a tape advancing slot  29  provided between the front end and the rear end of the outer shell  2 . The function of the tape advancing slot  29  will be described later. 
     As shown in FIGS. 3 and 7, the inner core  3  tapers from its rear end toward its front end. Each of the longitudinal engaging grooves  32  is formed on a respective side surface of the inner core  3  and extends forwardly downward for engagement with the corresponding roof margin  21  of the outer shell  2 , as previously described. The inner core  3  mainly comprises two integral portions, i.e., an upper portion located above the engaging grooves  32  and a lower portion located below the engaging grooves  32 . When the inner core  3  is assembled with the outer shell  2 , the upper portion is exposed, whereas the lower portion is enclosed in the outer shell  2 . 
     As shown in FIG. 1, the inner core  3  is provided, on its top, with an auxiliary tape guide groove  31  extending longitudinally of the bias tape maker A for guiding the auxiliary tape  12  toward the auxiliary tape entry window  5 . The guide groove  31  generally corresponds in width to the auxiliary tape  12 . As shown in FIG. 4, the guide groove  31  is defined by a bottom surface  31   b  and a pair of side walls  31   a . The bottom surface  31   b  has a width WT which is equal to or slightly larger than that of the auxiliary tape  12 . Each side wall  31   a  has a height which is larger than the thickness of the auxiliary tape  12 . Thus, it is possible to smoothly advance the auxiliary tape  12  along the guide groove  31 . 
     As shown in FIGS. 3 and 7, the inner core  3  is formed, at its rear end of the upper portion, with a handle  6  which is inclined backwardly upward. The handle  6  is formed with an auxiliary tape guide hole  61  (FIG. 7) for guiding the auxiliary tape  12 . The guide hole  61  has a width which is equal to or slightly larger than that of the auxiliary tape  12  for allowing insertion of the auxiliary tape  12 . As shown in FIG. 8, the guide hole  61 , the guide groove  31  and the window  5  are aligned longitudinally of the bias tape maker A. 
     As shown in FIG. 7, the lower portion of the inner core  3  below the engaging grooves  32  comprises a larger width portion  34 , a smaller width portion  35 , and a generally triangular portion  36 . The larger width portions  34  and the triangular portion  36  are continuous with each other and provides a flat upper surface  36   a  on each side of the auxiliary tape guide grove  31 . As shown in FIG. 3, each of the engaging grooves  32  is defined between this flat surface  36   a  and the corresponding side wall  31   a  of the guide groove  31 . The smaller width portion  35  is located below the larger width portion  34  and the triangular portion  36 . The upper surface of the smaller width portion  35  is divided by the triangular portion  36  into two triangular surfaces  35   a.    
     As shown in FIGS. 4 and 5, when the outer shell  2  and the inner core  3  are assembled, a tape inserting portion R 1  and a tape folding portion R 2  are formed between the outer shell  2  and the inner core  3 . The tape inserting portion R 1  extends from the rear end of the outer shell  2  for inserting the main tape  11 , whereas the tape folding portion R 2  extends from the tape inserting portion R 1  to the tape exiting port  24  for folding the longitudinal margins  11   a  of the main tape  11  toward each other. Specifically, in passing through the tape inserting portion R 1 , the main tape  11  is bent to have a U-shaped cross section with the longitudinal margins  11   a  raised. On the other hand, in passing through the tape folding portion R 2 , the longitudinal margins  11   a  of the main tape  11  are folded toward each other, thereby turning into a pair of folds  11   a.    
     For making an adhesive bias tape  1 , the above-described bias tape maker A may be used in the following manner. 
     First, a main tape  11  is introduced into the tape inserting portion R 1  from the rear end of the bias tape maker A. Then, the main tape  11  is advanced until the leading end of the main tape  11  is exposed at the tape advancing slot  29 . In this state, the user can advance the main tape  11  by making access to the main tape  11  via the tape advancing slot  29  directly with a finger or a short engaging article (not shown). In subsequently passing through the tape folding portion R 2 , the longitudinal edges  11   a  of the main tape  11  are folded toward each other, as described before. 
     Finally, the main tape  11  is pulled out from the tape exiting port  24  by the user nipping the leading end of the tape  11  (see FIG.  1 ). 
     Then, as shown in FIG. 1, an auxiliary tape  12  is introduced from the rear side of the handle  6  into the guide hole  61  and is advanced along the guide groove  31 . Then, the leading end of the auxiliary tape  12  is inserted through the window  5  into the bias tape maker A. The auxiliary tape  12  is pushed until its leading end projects out from the tape exiting port  24 . As shown in FIG. 6, upon passing in front of the inner core  3 , the auxiliary tape  12  lies on the folded longitudinal margins  11   a  of the main tape  11 . 
     While pulling out the auxiliary tape  12  together with the main tape  11  from the tape exiting port  24 , ironing may be performed from above the auxiliary tape  24 . As a result, the folded longitudinal margins  11   a  of the main tape  11  are fixed or set, and at the same time, the auxiliary tape  12  is bonded to the folded longitudinal margins  11   a  of the main tape  11 , thus providing an adhesive bias tape  1 . 
     With the bias tape maker A according to the present invention, it is possible to pull out the auxiliary tape  12  together with the main tape  11  from the tape exiting port  24  with the auxiliary tape  12  accurately positioned on the folded main tape  11 . Therefore, unlike the prior art bias tape maker, the user need not perform a separate step of accurately positioning the auxiliary tape relative to the main tape. Moreover, the setting of the folds  11   s  and the bonding of the auxiliary tape  12  to the main tape  11  can be performed simultaneously by a single ironing step. Therefore, it is possible to efficiently make an adhesive bias tape  1 . 
     Moreover, since the window  5 , the guide groove  31  and the guide hole  61  are aligned longitudinally of the bias tape maker A, the auxiliary tape  12  can be reliably and smoothly introduced into the window  5  and pulled out from the tape exiting port  24  without lateral rubbing. As a result, it is possible to prevent the auxiliary tape  12  from breaking due to friction. 
     Further, by holding the handle  6  of the inner core  3 , the user can press the bottom wall  22  of the outer shell  2  against the workbench, thereby preventing the adhesive bias tape  1  from being unexpectedly lifted from the workbench during ironing. Therefore, the ironing of the adhesive bias tape  1  can be performed efficiently. Since the guide hole  61  is formed at the base end of the handle  6 , the user can hold the handle  6  without contacting the auxiliary tape  12 , thereby preventing the auxiliary tape  12  from being undesirably deformed. Thus, the user can perform efficient ironing without the need for taking care not to deform the auxiliary tape  12 . 
     The preferred embodiment of the present invention being thus described, it is obvious that the same may be varied in many ways. For instance, the main tape  11  may be made of any material other than cloth or fabric. The bottom of the smaller width portion  35  may be formed with downwardly directed grooves to reduce the contact area between the main tape  11  and the smaller width portion  35  for enabling smooth movement of the main tape  11 . Such variations are not regarded as a departure from the spirit and scope of the present invention, and all such variations as would be obvious to those skilled in the art are intended to be included in the scope of the appended claims.

Technology Classification (CPC): 1