Abstract:
An improved tape supply system particularly suited for use in a multifunction tape applicator for applying a front and/or back L-clips to a case wherein a dancer roll is operable to provide slack in the tape and a break is applied to facilitate cutting of the tape.

Description:
FIELD OF INVENTION 
       [0001]    The present invention relates to an improved tape delivery system for a tape applicator for applying tapes to a case, more particularly to a delivery system for providing slack and stopping tension in the tape used in a multi-functional tape applicator for selectively applying closure tapes in different configurations such as L-clip and C-clip configurations 
       BACKGROUND OF THE PRESENT INVENTION 
       [0002]    Equipment for applying tape in a C-clip configuration is very well known and is commonplace in the literature and the industry. C-clip configuration generally applies a continuous ribbon of tape starting on a leading face of a case or carton passing through the machine along the surface of the case facing the taper and at least partway along the trailing face of the case i.e. the ribbon of tape forms a C-shape. 
         [0003]    L-clip configuration generally applies a ribbon of tape along two adjacent a faces of case e.g. around a corner of the case i.e. the ribbon of tape is formed into an L-shape. 
         [0004]    “L”-clip taping fulfills the “sustainability” packaging requirements in material and cost-saving comparing to the common “C”-clip taping. The concept of L-clip taping is known attention is directed to U.S. Pat. No. 4,640,731 that employs 2 separate applicators one to apply an L clip to the leading end and the other to apply an L clip to the trailing end of the case. U.S. Pat. No. 4,642,157 applies an L-clip using and application roll to apply the tape to one wall of the case and then a separate wipe down roll to apply the tape to an adjacent surface of the case. This device can only apply an L clip to the leading end of the case. Similarly U.S. Pat. No. 5,227,002 provides a device that can apply a tape in an L-clip configuration to leading face only of a case. 
         [0005]    Majority of carton closure do not require a continuous C-clip tape to seal the full length of the flaps, particularly carton package for the domestic business to business market where the tape sealed cartons are stacked, palletized and pallet wrapped with plastic film for shipping and storage. 
         [0006]    An L-clip configuration of a sealing tape is ideal for light weight cartons; single hinged flap cartons; tray carton with top lid; half slotted case, etc. 
         [0007]    The L-clips generally may be peeled off easily by hand without the use of box cutting knife, eliminating injuries and product damages when opening the carton with knife. 
         [0008]    In general, the adhesion and the strength of the pressure sensitive tape material are strong enough to withstand the weight of the content inside the carton with only the front and the back L-clips tape on top or at the bottom of the carton. 
         [0009]    C-clip taping provides a more secure and dust/inserts/tamper proof package. It is ideal for individual consumer package subject to multi-handling and or over-sea shipping. 
         [0010]    Regardless of all the obvious benefits of “L”-clip taping, the “C”-clip tape applicators are much more simple, reliable and user-friendly. Mostly operate mechanically without power-driven. They can be removed from the machine for tape replenishing with no tools. Because of its simplicity; low cost; easy to use and low maintenance as well as its long history of taping method, the popularity of C-clip taping remains very strong in the industry. 
         [0011]    The currently available L-clip tape applicators in the industry are dedicated for L-clip taping only, mostly operated by air cylinder with electrical control, meaning external sensors wiring and two power sources are required. Mechanical non-powered L-clip tape applicators with separated front and back units are too complicated since it has two individual tape rolls and other duplicated apparatus (see U.S. Pat. No. 4,640,731 referred to above). They are not particularly user-friendly. 
         [0012]    In general, L-clip tape applicators are much larger in size than conventional C-clip applicators and require more mounting space, extra wiring, special installation and a longer drive system to accommodate the tape applicator. Since the known L-clip tape applicators are dedicated for a single function, the carton sealing machine is dedicated for “L”-clip taping only. In situation where it is required to change the taping configuration, it is necessary to replace the entire tape applicator accordingly. The machine has to be shut down for the removal and disconnection of the existing unit and the installation, connection and set up of a different tape applicator. 
         [0013]    The concept of a multifunctional taper capable (with minor adjustments) to apply a tape selectively in a C-clip or L-clip configuration is taught in Applicant&#39;s co-pending U.S. patent application Ser. No. 12/318,877 filed: Jan. 12, 2009 inventor Joe Lam the disclosure of which is incorporated herein by reference. This machine has the capability of selectively applying a C-clip, a L-clip or, a pair of L-clips (a leading and trailing L-Clip applied respectively to the lead or trailing end of the case being sealed or closed). 
         [0014]    EPC application 0 259 241 describes a tape extender for extending the length of tape between a drag roll and the source of the tape (tape roll) and is an improvement for an apparatus for folding over the leading end of the tape to be applied to seal a carton in the conventional manner i.e. as a C-shaped tape application. This EPC Application 0 259 241 is specifically related to an apparatus for applying a length of tape and employs a drag between the tape supply roll and the lead applicator and operates to tension the tape between the supply roll and the drag as the tape is being pulled by movement of the case being taped and with the cut-off knife in inactive position and then to relieve said tension in the tape when the when the tape is cut by. cut off knife  150  in active cutting position. 
         [0015]    The present invention provides an improved tape delivery system that is particularly suitable for delivering tape to a tape applicator for applying an L-clip to the case and provides a system for clamping and providing slack in the tape (extending the tape) being delivered to the point of application to the case. 
       BRIEF DESCRIPTION OF THE PRESENT INVENTION 
       [0016]    It is an object of the present invention to provide an improved tape delivery system adapted to clamp the tape and to extend the tape to provide slack in the tape being delivered from a supply roll to a tape applicator for applying L-clip tape sections and in particular provides an improved delivery system for delivering tape to a multifunctional machine as described in the said U.S. patent application Ser. No. 12/318,877 filed: Jan. 12, 2009 (incorporated herein by reference) which is capable of changing from C-clip to front and/or back L-clips depending on the carton sealing requirement. 
         [0017]    Broadly the present invention relates to a tape supply system for a tape applicator for applying a closing tape ribbon to a carton comprising a frame for said tape applicator, a source of tape, a plurality of guide rolls arranged to define a tape path for a tape ribbon from said tape supply to an applicator for applying said tape to a case,
       one of said guide rolls being a dancer roll mounted to rotate on a first axis mounted on a dancer arm adjacent to one end of said dancer arm, said dancer arm being pivotably mounted on said frame on a second axis parallel to said first axis and positioned spaced from said first axis, a spring biasing said dancer arm to rotate in a counterclockwise direction around said second axis, a one way cam element pivotably mounted on a pivotal axis on said dancer arm and located between said first and second axis and a second spring biasing said cam to rotate in an anticlockwise direction on said pivotal axis,   a one way clutch roll pivotably mounted on said frame on a third axis parallel to said first axis, said one way clutch roll permitting rotation to permit movement of said tape along said tape path from said tape supply toward said applicator,   an applicator arm pivotably mounted on said frame on a forth axis parallel to said first axis, said applicator arm having an applicator adjacent to an end of said applicator arm remote from said danced arm, a co-operating cam element mounted on said applicator arm adjacent to its end remote from said applicator and positioned to engage said cam element and move said cam element and thereby said dancer arm in a clockwise direction around said second axis when said applicator arm is rotated clockwise around said fourth axis,   an applicator arm guide roll forming one of said guide rolls and being rotatably mount on said application arm for rotation about a fifth axis parallel to said first axis and positioned between said fourth axis and said applicator,   an exit roll forming one of said guide rolls mounted for rotation on said applicator arm on a sixth axis substantially parallel to said first axis and positioned on said applicator arm between said applicator arm guide roll and said applicator, said exit roll having a plurality of pin elements substantially parallel to said sixth axis and projecting from on axial end of said exit roll,   a stop cam fixed to said frame and positioned to interact with said pin elements when said application arm is rotated clockwise so that said stop cam is in an operative position wherein said stop cam engages said pin elements to stop rotation of said exit roll.   said tape path extending from said dancer roll to said one way clutch roll and then to said application arm guide roll, then to said exit roll and from said exit roll to said applicator.       
 
         [0025]    Preferably the tape supply system for a tape applicator for applying a closing tape ribbon to a carton further comprises a guide rod mounted on said frame and positioned to engage said tape ribbon 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0026]    Further features, objects and advantages will be evident from the following detailed description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings in which; 
           [0027]      FIG. 1  is a schematic illustration with parts omitted for clarity of a multifunctional tape applicator as described in detail in U.S. patent application Ser. No. 12/318,877 filed: Jan. 12, 2009 inventor Joe Lam with the present invention incorporated therein to replace the earlier tape extender and showing the applicator arm in rest or initial position. 
           [0028]      FIG. 2   a  is schematic plan isometric illustration with parts omitted for clarity showing the stop cam and exit roll. 
           [0029]      FIGS. 2   b  and  2   c  each shows a schematic side elevation with parts omitted for clarity of two different forms of stop cam and guide pin and their interaction with the exit roll when the stop cam is in position to stop rotation of the exit roll. 
           [0030]      FIG. 3   a  is a schematic illustration with parts omitted for clarity showing the applicator arm in position with the applicator after initial contact with the leading face (leading in the direction of travel of a case through the machine). 
           [0031]      FIG. 3   b  is a schematic illustration similar to  FIG. 3   a  with the applicator arm in position wherein the co-operating cam element and the cam element have engaged to rotate the dancer arm clockwise as the applicator arm is also rotated clockwise by engagement of the applicator with the case being taped. 
           [0032]      FIG. 3   c  is a schematic illustration with parts omitted showing the applicator in an advanced position relative to  FIG. 3   b  wherein the co-operating cam element and the cam element are about to disengage in the over-travel position and showing the exit roller stopping the tape for cutting and completing the first L-clip taping to a case. 
           [0033]      FIG. 3   d  is a schematic illustration with parts omitted showing the applicator further in the over-travel position after the application of an L-clip to a case and showing co-operating cam element and the cam element disengaged and the dancer arm rotating counterclockwise to it rest position. 
           [0034]      FIG. 3   e  is a schematic illustration similar to  FIG. 3   d  showing the applicator arm at the start of its counterclockwise rotation as the applicator arm is returning from its over travel position to apply the second L-clip. 
           [0035]      FIG. 3   f  is a schematic illustration similar to  FIG. 3   d  showing the applicator arm as the applicator arm is returning from its taping position toward its initial position after tape cutting and case has cleared. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0036]    Turning to  FIG. 1  a multifunctional tape applicator  10  with the tape supply system  12  of the present invention incorporated therein. The applicator includes a frame  14  having a pair of substantially parallel panes namely a front panel  16  and a back panel  18  connected together in spaced apart relationship by bolts  20  with spacers between the panels  16  and  18 . The components of the applicator  10  are generally positioned between the panels  16  and  18  with some components mounted from the front panel  16  and others from the back panel  18  as will be described below. 
         [0037]    Applicator as described in detail in U.S. application Ser. No. 12/318,877 filed: Jan. 12, 2009 inventor Joe Lam and includes an applicator arm  24  which at one end mounts an applicator  26  which in the illustrated version is in the form of an applicator roll and at its opposite end located adjacent to the adhesive tape source or roll  30  is a cam  28 . 
         [0038]    The remainder of the illustrated components of multifunction tape applicator includes the connecting arm interconnecting the arm  32  and the trailing arm  34  with the slide cam  35  in position to operate and have the applicator move to over travel position wherein the applicator  26  is positioned above the adjacent surface of the case  100  being processed (see  FIG. 2  or  3 ). Full details of the applicator as indicated above are describe in the said US patent application The tape supply system added by the present invention includes a first guide roll  36  of a plurality of guide rolls that define a tape path  38  for a ribbon of tape  40  that is drawn from the roll  30  in the operation of the device. The roll  36  is mounted between the panels  16  and  18  of the frame  14 . 
         [0039]    The next guide roll of the plurality of guide rolls defining the tape path  38  is a dancer roll  42  which is mounted to rotate on a first axis  44  that is mounted at one end of a dancer arm  46  which in turn is mounted at its opposite end to rotate on a second axis  48 . Also mounted on the dancer arm  46  for rotation on a pivotal axis  50  is a one way cam element  52  having a one way cam surface  54  and a rear surface  56 . The arm  46  is biased to rotate counterclockwise (i.e. anticlockwise) about the second axis  48  by a spring  59  connecting the end of the arm  46  adjacent to the roll  42  to the frame  14  and the one way cam element  52  is biased to rotate in an anticlockwise direction around the pivotal axis  50  by a spring  61  interconnecting the arm  46  with the one way cam at a location on cam  52  on the opposite side of the pivotal axis  50  relative to the cam surface  54 . 
         [0040]    A one way clutch roll  58  i.e. a roll that can only rotate in one direction in this case only can rotate in the clockwise direction is mounted on the frame  14  to rotate on a third axis  60  and to permit the tape  40  to advance along the tape path  38  toward the applicator, but not rearward toward the tape supply roll  30  is the next guide roll defining the tape path  38 . 
         [0041]    The applicator arm  24  is pivotably mounted on the frame  14  to rotate on a fourth axis  62 . Two other of the guide rolls forming the path  38  are mounted to the applicator arm  24  namely guide roll  64  and exit roll  66  which rotate on a fifth axis  68  and the sixth axis  70  respectively From the roll  58  the tape ribbon  40  passes around the guide roll  64  defining the path  38  and from there around the exit roll  66  which is positioned between the roll  64  and the applicator  26  and then to the applicator  26 . 
         [0042]    The tape ribbon  40  has its adhesive side facing and contacting the guide roll  36 , the one way clutch roll  58  and the exit roll  66   
         [0043]    It will be apparent that all of the above described axes are parallel. 
         [0044]    A stop cam  72  and guide rod  74  are mounted cantilever fashion from the front wall  16  and project toward the back wall  18  and are in position to interact with the exit roll  66  without interfering with the movement of the applicator arm  24  to an over travel position as is more clearly illustrated in  FIG. 2   a . As shown in  FIG. 2   a . the exit roller is cantilevered from the arm  24  and at its free end is provided with a plurality of axially extending pin elements  76  (three in the illustrated embodiment) symmetrically positioned around the sixth axis  70 . It will be evident that the stop cam  72  engages with one of these pins  76  when the arm  24  is in over travel position as will be described below. 
         [0045]    The sequence of operation of the tape extender formed by the dancer roll  42  and its mounting for relative movement to the frame  14 . As shown in  FIG. 3   a  at the commencement of the taping operation the case  100  being closed is moved against the applicator  26  which in the illustrated arrangement is in the form of a roll that wipes the leading end of the tape ribbon  40  against the leading face  102  of the case with the adhesive side of the tape  40  in contact with the leading face  102  of the case  100 . As the case is advanced the applicator moves over the top (or bottom depending on the orientation of the case relative to the applicator)  104  of the case  100  which forces the arm  24  to rotate in a clockwise direction as indicated by the arrow  106  in  FIG. 3   b  which moves the cam  28  against the cam face  54  of the cam  52  and forces the cam  52  and the dancer arm  46  to rotate clockwise about axis  48  and thereby move the dancer roll away from the one way clutch roll  58  and extend the length of the tape path  38  between the tape roll  30  and the roll  58  to provide an extended length of tape  40 . Next the arm  24  is moved toward over travel position as shown in  FIG. 3   c  and the cut off knife  150  is positioned to cut and cuts the ribbon  40  as indicated at  152  to apply and L-clip tape to the leading corner of the case  100 . In this position the cam  28  is about to clear the cam face  54  of the cam  52  and the dancer roll  42  is in its fully extended position stretching the spring  59  and maximizing the length of the tape path  38  between the tape roll  30  and the one way clutch roll  58 . In  FIG. 3   d  the arm  24  has reached full over travel position with the applicator  26  well above the top  104  of the case  100  and the cam  28  is clear of the cam face  54  of the cam  52  and the spring  59  contracts bringing the dancer roll  42  and arm  46  back to their starting positions as indicated by the arrows  160  and  162  and providing slack in the tape  40  as indicated at  164 . 
         [0046]    In the illustrated system the arm  24  is then moved to the top  104  of the of the case  100  and a L-clip is applied to the trailing end  110  of the case  100  as described in full in the said US patent application (see  FIG. 3   e  and the slack  164  is used to begin the formation of this L-clip applied along the top  104  of the case  100  adjacent to the trailing end  110  of the case. After the applicator  26  clears the trailing end  110  of the case  100  it returns to the starting position and in so doing the cam  28  engages the rear face  56  of the cam element  52  and moves same against the resistance of the spring  61  (see  FIG. 3   f ) so that the arm  24  can return to starting position as shown n  FIG. 3   a.    
         [0047]    When the arm  24  is in over travel position the stop cam  72  engages the pins  76  to prevent rotation of the exit roll  66  and to which the adhesive side of the tape  40  is adhered to stop movement of the tape  40  to permit proper cutting of the tape by the knife  150 . The rod  74  forces the tape  40  to more fully surround the exit roll  66  and thereby increase the area of contact between the adhesive tape  40  and the exit roll  66  (see  FIG. 2   b  and  FIGS. 3   c  and  3   d ). 
         [0048]      FIG. 2   c  shows a modification of the breaking cam  72 A and rod  74 A (equivalent to the cam  72  and rod  74 ) wherein the two are substantially concentric and position on the up-stream side of the exit roll  66  which permits exit roll  66  to rotate clockwise for more tape cutting tension. Having described the invention, modifications will be evident to those skilled in the art without departing from the scope of the invention as defined in the appended claims.