Abstract:
A debris separator pre-separates debris from a label tape, the label tape including a carrier web and a label material, the label material being half cut into labels and debris that surround all around individual labels. The label tape is transported in a path. A first roller is disposed in the path, extends in a direction, and is covered with an elastic member. A second roller is disposed in the path, extends parallel to the first roller, and includes elastic members angularly disposed on the second roller. The elastic members have circumferential surfaces. A controller controls the first and second rotatable bodies. The first and second rollers rotate with the label tape sandwiched between their circumferential surfaces, the second circumferential surface digging into the first circumferential surface and the first circumferential surface pushing back the debris to detach the debris at least partially from the web.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention generally relates to a label separator and a label printing system. 
         [0003]    2. Description of the Related Art 
         [0004]    A composite label tape is comprised of a carrier web and label material releasably adhered by an adhesive to the carrier web. The label material includes labels and residues or debris that surround each label. Each label is removed from the carrier web, leaving the surrounding residues on the web, and is applied to a product surface. Japanese Patent Publication No. 2006-181860 discloses one type of residue separator configured to separate the residue material from the carrier web. The apparatus comprises a mechanism which includes a separator member that peels the residues of the label material from the web. The separator member is effective in preventing the labels from being peeled together with the residue material. 
         [0005]      FIG. 14  illustrates the label tape when the residues are peeled. However, the apparatus suffers from the following drawbacks. The label tape includes a web  9 , half cut labels  10  and a residue  11 , which are attached on surface of the web  9  by means of an adhesive. The residues include a portion  11   a  that extends in a direction parallel to a direction in which the label tape is paid out. When the residues begin to be peeled off from the web  9 , the portion  11   a  is first peeled substantially in the direction in which the label tape is paid out. A portion  11   b  extends substantially in a direction perpendicular to the residue  11   a  and begins to be peeled off at its longitudinal ends. When the portion  11   b  leaves the web  9 , unpleasant noise occurs. If the portion  11  is strongly adheres to the web  9 , the portion  11   b  may break at its middle portion  11   c.    
       SUMMARY OF THE INVENTION 
       [0006]    The present invention was made to solve the drawbacks of conventional apparatus for removing residues of the label material of a half cut label tape. 
         [0007]    An object of the invention is to provide a label separator and a label printing system that do not make unpleasant noise. 
         [0008]    A debris separator pre-separates debris from a label tape, the label tape including a carrier web and a label material, the label material being half cut into labels and debris that surround all around individual labels. The label tape is transported in a path. A first roller is disposed in the path, extends in a direction, and is covered with an elastic member. A second roller is disposed in the path, extends parallel to the first roller, and includes elastic members angularly disposed on the second roller. The elastic members have circumferential surfaces. A controller controls the first and second rotatable bodies. The first and second rollers rotate with the label tape sandwiched between their circumferential surfaces, the second circumferential surface digging into the first circumferential surface and the first circumferential surface pushing back the debris to detach the debris at least partially from the web. 
         [0009]    Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the scope of the invention will become apparent to those skilled in the art from this detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and wherein: 
           [0011]      FIG. 1  is a perspective view of a label printing system according to the present invention when a continuous label tape roll has not been loaded yet; 
           [0012]      FIG. 2  is a top view as seen in a direction shown by arrow A in  FIG. 1 ; 
           [0013]      FIG. 3  is a front view as seen in a direction shown by arrow B in  FIG. 1 ; 
           [0014]      FIG. 4  is a perspective view of the label printing system when the label tape has been loaded; 
           [0015]      FIG. 5  is a top view as seen in a direction shown by arrow D in  FIG. 4 ; 
           [0016]      FIG. 6  is a side view as seen in a direction shown by arrow E in  FIG. 4 ; 
           [0017]      FIG. 7A  illustrates the pertinent portions of a pre-separation mechanism; 
           [0018]      FIG. 7B  illustrates an annulus sector; 
           [0019]      FIG. 7C  is a perspective view of a slit disc and a slit detector; 
           [0020]      FIG. 7D  is a top view as seen in a direction shown by arrow F in  FIG. 7C ; 
           [0021]      FIG. 8A  is a top view of the label tape; 
           [0022]      FIG. 8B  is a side view of the label tape when the label tape has been partially paid out; 
           [0023]      FIG. 8C  is a cross-sectional view taken along lines  8 C- 8 C in  FIG. 8A ; 
           [0024]      FIG. 9  illustrates the positional relationship between an upper roller assembly and a lower roller assembly when a mark line on the label tape has not been detected by the mark detector yet; 
           [0025]      FIG. 10  illustrates the operation of the pre-separation mechanism; 
           [0026]      FIGS. 11A, 11B, and 12  illustrate elastic members of the lower roller assembly when the elastic member is pushed into the elastic member of the upper roller assembly; 
           [0027]      FIG. 13  is an expanded view of a pertinent portion in the vicinity of a half cut line printed on the label tape; and 
           [0028]      FIG. 14  illustrates a prior art label tape when residues are peeled from the label tape. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0029]    By way of preferred embodiments, the present invention will be described in detail with reference to the accompanying drawings. 
       First Embodiment 
       [0030]    The label tape according to the invention includes a web, a label material, and an adhesive in a laminated structure, the label material being adhered to the web by the adhesive. 
         [0031]    The label material is a sheet, which is half cut to define labels and residues or peripheral portions, the residue surrounding each label. The residue includes portions  11   a  that extend in directions parallel to the direction in which the label tape advances, and portions  11   b  that extend in directions perpendicular to the portions  11   a.    
       {Configuration} 
       [0032]      FIG. 1  is a perspective view of a label printing system  100  when the continuous label tape roll has not been loaded yet.  FIG. 2  is a top view as seen in a direction shown by arrow A of  FIG. 1 .  FIG. 3  is a front view as seen in a direction shown by arrow B. The label tape advances or is paid out in a direction shown by arrow C as shown in  FIG. 1 . 
         [0033]      FIG. 4  is a perspective view of the label printing system  100  when the label tape  8  has been loaded.  FIG. 5  is a top view as seen in a direction shown by arrow D of  FIG. 4 .  FIG. 6  is a side view as seen in a direction shown by arrow E in  FIG. 4 . 
         [0034]    Referring to  FIGS. 1 and 2-6 , the label printing system  100  constitutes of a label printer  1  as a printing device, a pre-separation mechanism  19 , and a post-separator  2 . 
         [0035]    The label printing system  100  is configured to print on the label material releasably adhered to one side of the web by an adhesive ( FIG. 8C ). 
         [0036]    The roll of label tape  8  is rotatably supported on the label printer  1  via a supporting mechanism (not shown). The label tape  8  is paid out from the roll, and information is then printed on the label material. The label printer  1  pays out the printed label tape  8  through an exist  14  ( FIGS. 1 and 4 ) to the pre-separation mechanism  19 . 
         [0037]    The pre-separation mechanism  19  is located between the label printer  1  and the post-separator  2 , and is fixed to the printer  1  and the post-separator  2  by means of an appropriate means (not shown). The pre-separation mechanism  19  detaches the residues or debris  11   b  from the label tape  8 , leaving the labels  10  behind and allowing the labels  10  to remain attached to the web  9  until the label tape  8  arrives at the post-separator  2 . 
         [0038]    A controller (not shown) sends command signals to the label printer  1  and the pre-separation mechanism  19  over cables, thereby driving the label printer  1  and the pre-separation mechanism  19  in synchronism. The pre-separation mechanism  19  drives its mechanical elements in accordance with the command signals, thereby properly transporting the label tape  8 . 
         [0039]      FIG. 7A  illustrates the pertinent portions of the pre-separation mechanism  19 .  FIG. 7B  illustrates an annulus sector. An upper guide  24  and a lower guide  25  are substantially in the shape of a narrow plate, and extend straightly from the printer  1  to the post-separator  2 . The upper and lower guides  24  and  25  are supported on a frame (not shown) with a predetermined space therebetween to define a label path  36  through which the label tape  8  advances. The label path  36  has an entrance that opens to the label printer  1  and an exit that opens to the post-separator  2 . Each of the upper and lower guides  24  and  25  has an opening  24   a  or  25   a  through which the upper or lower feed roller  23  or  21  partially enters the path  36 . The opening is located upstream of the upper and lower roller assemblies  30  and  33 . 
         [0040]    A lower feed roller  21  and an upper feed roller  23  are disposed upstream of the upper and lower roller assemblies  30  and  33 , and cooperate with each other to transport the label tape  8  sandwiched therebween toward the upper and lower roller assemblies  30  and  33 . The lower feed roller  21  and the upper feed roller  23  partially enter the label path  36 , and rotate each other to feed the label tape  8  to the upper and lower roller assemblies  30  and  33 . The upper and lower feed rollers  23  and  21  each have a plurality of sub rollers as shown in  FIG. 4 . The lower feed roller  21  and upper feed roller  23  constitute an upstream feed roller pair. An upper feed roller  22  and a lower feed roller  20  are disposed downstream of the upper and lower roller assemblies  30  and  33 , and cooperate with each other to transport the label tape  8  sandwiched therebetween. The upper and lower feed rollers  22  and  20  each have a plurality of sub rollers as shown in  FIG. 4 . The upper feed roller  22  and lower feed roller  20  constitute a downstream feed roller pair. Each of the upper and lower guides  24  and  25  has an opening  24   b  or  25   b  through which the upper or lower feed roller  23  or  21  partially enters the path  36 , the opening  24   b  or  25   b  being located downstream of the upper and lower roller assemblies  30  and  33 . The upper feed roller  22  and the lower feed roller  20  partially enter the label path  36  and rotate to feed the label tape  8 . When the label tape  8  passes through the gap between the upper and lower feed rollers  22  and  20  after the debris  11   b  has been peeled off the web  9 , the upper feed roller  22  and the lower feed roller  20  hold the label tape  8  therebetween and rotate to further transport the label tape  8 . Once the debris  11   b  has been peeled off the web  9 , the debris  11   b  will not adhere to the web again even though the upper feed roller  22  and the lower feed roller  20  hold the label tape  8  therebetween in a sandwiched relation. 
         [0041]    The upstream and downstream feed roller pairs are rotatably supported on a frame (not shown), and are driven in rotation by a drive source, e.g., a motor so that the upstream and downstream feed roller pairs cooperate with each other to transport the label tape  8  in accordance with the control commands from the controller. 
         [0042]    An upper roller assembly  30  and a lower roller assembly  33  are disposed between the upstream and downstream feed roller pairs. A mark detector  26  is located under the lower guide  25  immediately upstream of the lower roller assembly  33 . 
         [0043]    The upper roller assembly  30  is rotatably supported on a side frame (not shown) above the upper guide  24 , and is mechanically coupled to the upstream feed roller pair and the downstream feed roller pair, so that the upper roller assembly  30  rotates in synchronism with the upstream and downstream feed roller pairs. 
         [0044]    The lower roller assembly  33  is rotatably supported on a side frame (not shown) under the lower guide  25 , and is mechanically coupled to a drive mechanism different from that of the upper roller assembly  30 , so that the lower roller assembly  33  rotates independently of the upper roller assembly  33 . The upper roller assembly  30  and the lower roller assembly  33  have their rotational axes that lie in the same vertical plane. 
         [0045]    The mark detector  26  detects a black marker line  12 , which is printed on a side of the web  9  opposite the labels  10  and indicates the position of the information printed on a corresponding label  10 . The detection signal of the mark detector  26  is sent to the controller, and is used to controllably drive the pre-separation mechanism  19 . The mark detector  26  may be disposed at any location as long as it is located upstream of the lower roller assembly  33 , and downstream of the label printer  1 . 
         [0046]      FIGS. 8A and 8B  illustrate the configuration of the label tape  8 .  FIG. 8C  is a cross-sectional view taken along lines  8 C- 8 C of  FIG. 8A .  FIG. 8A  is a top view of the label tape  8 .  FIG. 8B  is a side view of the label tape  8  when the label tape  8  has been partially paid out. Referring to  FIG. 8C , the label tape  8  includes the web  9 , labels  10 , an adhesive coating  15 , and the debris or residue  11 . The label tape  8  is paid out in a direction shown by arrow H. As shown in  FIG. 8C , the label material is half cut at boundaries  13 , which surround each label  10 , into the labels  10  and the debris  11  surrounding the labels  10 , so that the labels  10  and the debris  11  still adhere to the web  9  but the labels  10  can be separated from the web  9  without difficulty at a later stage. Thus, the debris  11  can be peeled off from the web  9  while the labels  10  remain releasably adhered to the web  9 . 
         [0047]    The mark line  12  is printed in a projected area, which is defined by projecting the label  10  onto a side of the web  9  opposite the label  10 . The mark line  12  is in the vicinity of the trailing end of the label  10  with respect to the advance direction C of the label tape  8 . The mark line  12  indicates a position where the information is printed on the label  10 . 
         [0048]    Referring to  FIG. 7A , the upper roller assembly  30  includes an upper roller shaft  31  rotatably supported on the side frame (not shown), and an elastic member  32  that covers the circumferential surface of the upper roller assembly  30 . The elastic member  32  is formed of, for example, sponge. 
         [0049]    The lower roller assembly  33  includes a slit disc  28 , a lower roller shaft  34 , and four elastic members  35 . The slit disc  28  has four slits  29  angularly equally spaced by 90°, the slits radially extending and having an identical shape. Each of the elastic members  35  has a cross-section in the shape of an annulus sector, and extends in a direction parallel to the lower roller shaft  34  ( FIG. 12 ), and a leading edge  35   a  and a trailing edge  35   b  with respect to the rotation of the lower roller assembly  33 . Annulus sector is a shape ( FIG. 7B ) that has a center C, the opening angle  6 , and the radii 0&lt;r&lt;R of the two circular arcs bounding it. The elastic members  35  are formed of, for example, a rubber material. 
         [0050]    The slits  29  are angularly equally spaced such that each slit is shifted by 90° in phase relative to the elastic member  35 . In other words, each slit  29  is positioned angularly in the middle of adjacent elastic members  35 . 
         [0051]      FIG. 7C  is a perspective view of the slit disc  28  and a slit detector  27 .  FIG. 7D  is a top view as seen in a direction shown by arrow F in  FIG. 7C . The slit detector  27  is mounted on a frame (not shown), and includes a light source  27   a  and a light receiving section  27   b.  The slit detector  27  detects the slits  29  formed in the slit disc  28  when the slit disc  28  rotates. The detection signal of the slit detector  27  is sent to the controller over a cable. In response to the detection signal, the controller sends a command to stop the rotation of the lower roller assembly  33 . 
         [0052]      FIG. 9  illustrates the positional relationship between the upper roller assembly  30  and the lower roller assembly  33  when the mark line  12  has not been detected by the mark detector  26  yet. 
         [0053]    The elastic member  35  of the lower roller assembly  33  has a hardness of A and the elastic member  32  of the upper roller assembly  30  has a hardness of B. The hardness are selected such that A is greater than B. 
         [0054]    When the upper and lower roller assemblies  30  and  33  rotate, the elastic member  35  is brought into contact with the elastic member  32  of the upper roller assembly  30 , so that the elastic member  35  is pushed or dug into the elastic member  32 . Reference character D denotes an amount of dig by which the elastic member  35  is pushed into the elastic member  32  ( FIG. 9 ). 
         [0055]    When the elastic member  35  digs strongly into the elastic member  32 , the label  10  is pushed downward by the elastic member  32  while the label tape  8  is pushed upward by the leading edge  35   a  ( FIG. 11A ) of the circumferential surface of the elastic member  35 . This causes the debris  11   b  to separate from the web  9 , creating a small area S ( FIG. 11B ) between the debris  11   b  and the web  9 . As a result, the debris  11  in the vicinity of the half cut line  13  is detached from the web  9 . The circumferential dimension of the elastic member  35  should be at least as long as the width of the debris  11   b.    
         [0056]    The post-separator  2  is located downstream of the pre-separation mechanism  19 , and receives the label tape  8  whose debris  11  has been detached from the web  9  in the vicinity of the half cut line  13 . The post-separator  2  separates the debris  11  from the web  9 , leaving only the labels  10  adhered to the web  9 . 
         [0057]    Referring to  FIGS. 2 and 6 , a guide roller  6  receives the label tape  8 , and cooperates with a separator bar  7  to separate the debris  11  from the web  9 . The guide roller  6  and the separator bar  7  are rotatably supported on a frame (not shown), and are configured to rotate freely. The debris  11  is then wound on a debris take-up spool  5 . The web  9  on which the labels  10  remain attached is further advanced by the guide roller  6  and is wound on a web take-up spool  3 , which is at a downstream end of the label advance direction. The web take-up spool  3  includes flanges  4  that are disposed at longitudinal end portions of the web take-up spool and guide the web  9  so that the web  9  is wound on the web stake-up pool  3  smoothly without misalignment. The web take-up spool  3  and the debris take-up spool  5  are driven in synchronism by a drive mechanism (bot shown). 
       {Operation} 
       [0058]    The operation of the label printing system  100  will be described in detail with reference to  FIGS. 10-13 . 
         [0059]      FIGS. 7A-7D and 10-13  illustrate the operation of the pre-separation mechanism  19 . 
         [0060]    The label printer  1  prints on the labels  10  of the label tape  8 . The label tape  8  is then paid out through the exit  14  into the label path  36  defined by the upper guide  24  and the lower guide  25 . 
         [0061]    The label tape  8  is transported by the upstream feed roller pair constituted of the upper and lower feed rollers  23  and  21 , which rotate at a circumferential speed equivalent to the speed at which the label tape  8  is paid out. The label tape  8  enters the pre-separation mechanism  19  defined between the upper roller assembly  30  and the lower roller assembly  33 . 
         [0062]    The upper roller assembly  30  is mechanically coupled to the upstream roller pair and the downstream roller pair. Thus, the upper roller assembly  30  rotates in synchronism with the upstream and downstream roller pairs. On the other hand, the lower roller assembly  33  is not mechanically coupled to the upstream and downstream roller pairs. Therefore, the lower roller assembly  33  in  FIG. 9  is at rest. 
         [0063]    When the lower roller assembly  33  is at rest, the four elastic members  35  slightly extend into the label path  36  or are completely out of the label path  36 . At this moment, the leading edge  35   a  of the elastic member  35 - 2  may or may not come in slight contact with the back surface of the web  9 , so that the elastic member  35 - 2  will not interfere with the label tape  8  that advances through the label path  36 . 
         [0064]    Referring to  FIG. 9 , the mark detector  26  detects the black mark line  12  printed on the back side of the web  9 , and sends the detection signal to the controller upon detection of the mark line  12 . 
         [0065]    The label tape  8  is further advanced a distance Y ( FIG. 10 ) for a short period of time t shortly after detection of the mark line  12 . At the end of the short period of time t, the controller drives the lower roller assembly  33  into rotation. 
         [0066]    It is desirable that the lower roller assembly  33  starts to rotate when the mark line  12  arrives substantially at the leading edge  35   a  of the elastic member  35 - 2 . The distance Y ( FIG. 10 ) may be selected in accordance with the dimension L ( FIG. 8A ) of the label  10  extending in the advance direction of the label tape  8 . 
         [0067]    As shown in  FIG. 11A and 11B , the elastic member  35  comes into rolling pressure contact with the elastic member  32  of the upper roller assembly  30 , and then digs into the elastic member  32 . 
         [0068]      FIGS. 12 and 13  illustrate the elastic members  32  and  35  when the elastic member  35  is pushed into the elastic member  32 .  FIG. 13  is an expanded view of a pertinent portion in the vicinity of the half cut line  13 . 
         [0069]    Referring to  FIG. 13 , when the elastic member  35  is pushed into the elastic member  32 , the elastic member  35  and elastic member  32  are positioned relative to each other such that the half cut line  13  is a distance Z downstream of the leading edge  35   a  of the elastic member  35 . Referring back to  FIGS. 11A and 11B , the distance Z is a distance between the leading edge  35   a  and the half cut line  13 . 
         [0070]    When the label tape  8  is sandwiched between the elastic member  32  and the elastic member  35 , the debris  11  sits on the circumferential surface of the elastic member  35  while the label  10  and web  9  is pressed downward by the elastic member  32  at an area immediately downstream of the leading edge  35   a  of the elastic member  35  with respect to the advance direction of the label tape  8 . Therefore, the debris  11  is separated from the web  9  at the half cut line  3 . In this manner, portions  11   b  of the debris  11 , which would otherwise make unpleasant sounds at the post-separator  2 , are separated from the web  9  before the label tape  8  arrives at the post-separator  2 . 
         [0071]    The upper and lower feed roller pairs continue to rotate so that the label tape  8  further advances as shown in  FIG. 10 . When the slit  29  passes the sensor  27 , the sensor  27  detects the slit  29  and sends the detection signal to the controller. In response to the detection signal, the controller drives the drive mechanism to stop the rotation of the lower roller assembly  33 , so that the lower roller assembly  33  comes to rest. 
         [0072]    As described above, the operation of the pre-separation mechanism  19  illustrated in  FIGS. 9, 11A and 11B  is repeated for each debris portion  11   b,  so that the debris portions  11   b  are detached from the web  9  before label tape  8  arrives at the post-separator  2 . 
         [0073]    The post-separator  2  receives the label tape  8  whose debris portions  11   b  have been detached, and removes only the entire debris  11  is from the web  9 , leaving only the labels  10  on the web  9 . 
         [0074]    Pre-separating the debris portions  11   b,  which extends in a direction perpendicular to the direction in which the label tape  8  advances, provides smooth, quiet debris-separating operation at the post-separator  2 , reducing unpleasant noise or sounds as well as preventing cutting off of the debris  11  in the middle of the removal operation of the debris  11  at the post separator  2 . 
       {Modifications} 
       [0075]    The present invention is not limited to the above-described embodiment, and may be modified in a variety of ways. For example, the present invention may be applied to an apparatus configured to partially separate the leading edge portions of the labels on a label tape whose debris have been completely removed, so that the labels can be easily separated from the web of the label tape when the label is actually affixed to a product at a later stage. 
         [0076]    The four elastic members  35  have been described as having a cross section in the shape of an annulus sector, and the corner of the leading edge  35   a  of the elastic member  35  pushes up the label material in the vicinity of the half cut line  13 . Alternatively, the number of the elastic members  35  may be increased as long as the corner of the leading edge  35   a  pushes up the label material in the vicinity of the half cut line  13 . 
         [0077]    The sensor  27  has been described as detecting the slit  29  to stop the rotation of the lower roller assembly  33 . Alternatively, the sensor  27  may be configured to detect other type of mark e.g., a line instead of the slit  29 , as long as the mark properly indicates a position or timing to stop the lower roller assembly  33  and is detected reliably. 
         [0078]    The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.