Abstract:
A case sealing device is provided for applying a sealing tape to a surface of a case to be sealed. The device includes a work surface. A first portion of the work surface defines an entry region and a second portion of the work surface defines an exit region. A taping assembly is mounted adjacent the work surface between the entry region and the exit region. The taping assembly includes a taping head and a taping head linkage. The linkage has a rotatable first end and a second end. The second end is secured to the taping head. The taping head is adapted to hold an associated roll of tape. The taping head and the taping head linkage are configured to cooperate to dispense a strip of the tape from the taping head onto the surface of the case to be sealed as the case to be sealed is brought into contact with the taping assembly during sliding movement from the entry region to the exit region of the work surface.

Description:
A claim for domestic priority is made herein under 35 U.S.C. §119(e) to U.S. Provisional App. Ser. No. 60/854,311 filed on Oct. 24, 2006, the entire disclosure of which is incorporated herein by reference. 

   BACKGROUND 
   The present application relates to the general field of packaging. It finds particular application to packaging equipment used to tape or seal shipping containers, cases, boxes, or cartons and will be described with reference thereto. However, other applications are also contemplated. 
   It is well known that merchandise and the like are commonly shipped or transported in rectangular cardboard containers or cases. Typically, these cases are supplied as a flat sheet and must be erected (or folded into a rectangular cube) and partially sealed before they can be used. In high volume shipping and packaging facilities, this process is performed by an automatic machine known as a case erector/sealer. In lower volume facilities, the cases are individually erected and manually sealed using a handheld unit commonly referred to as a “taping gun.” 
   For reasons which are obvious, manually erecting and sealing cases is laborious and, in particular, time consuming. In addition, handheld taping guns are not consistent in applying a reliable tape seal. In many instances, the user must hold the loose or open flaps of the case closed while attempting to operate the taping gun in sealing the case. Since sealing a case is a relatively precarious operation for a single individual, portions of the sealing tape often fail to adhere reliably to the case, fold and adhere to itself, or otherwise adhere in an improper or off-center location on the case. For example, if the end portions of the tape are not adhered properly, they could catch on a foreign object causing the tape to become detached and possibly spoiling the case. 
   On the other hand, automatic case erectors/sealers are complicated to operate, require frequent maintenance, and are cost prohibitive for many medium and small sized businesses. In addition, automatic case sealers are typically limited to a specific range of case sizes. 
   For at least these reasons, a need exists to provide a simple, versatile, reliable, and cost effective case sealing machine designed to accommodate medium to low volume packaging operations. Thus, the present application provides an improved device and a method that overcome the aforementioned problems and others. 
   SUMMARY 
   According to one aspect of the present invention, a case sealing device is provided for applying a sealing tape to a surface of a case to be sealed. The device includes a work surface. A first portion of the work surface defines an entry region and a second portion of the work surface defines an exit region. A taping assembly is mounted adjacent the work surface between the entry region and the exit region. The taping assembly includes a taping head and a taping head linkage. The linkage has a rotatable first end and a second end. The second end is secured to the taping head. The taping head is adapted to hold an associated roll of tape. The taping head and the taping head linkage are configured to cooperate to dispense a strip of the tape from the taping head onto the surface of the case to be sealed as the case to be sealed is brought into contact with the taping assembly during sliding movement from the entry region to the exit region of the work surface. 
   According to another aspect of the present invention, a method is provided of sealing a surface of a case to be sealed with tape. The method includes advancing a case to be sealed along a work surface. A first end of a length of the tape extending along an applicator surface contacts a first wall surface of the advancing case to adhere the first end of the tape to the first wall surface. With continued advancement of the case to be sealed, a linkage that supports the applicator surface is rotated while the tape is dispensed against the first wall surface of the advancing case. With continued advancement of the case to be sealed, the linkage is further rotated to cause the applicator surface to round a forward edge of the advancing case. With continued advancement of the case to be sealed, the tape is pressed against a second wall surface of the advancing case. With continued advancement of the case to be sealed, the tape is cut and a cut end portion of the tape is adhered against a third wall surface of the advancing case. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention may take form in various components and arrangements of components and various steps and arrangement of steps. The drawings are only for purposes of illustrating various embodiments of the invention and are not to be construed as limiting the invention. 
       FIG. 1  is a perspective view from a right or front side of a first embodiment of a case sealing device illustrating a work table, a self-centering guide assembly, and an articulated taping head assembly. 
       FIG. 2  is a perspective view from a right or rear side of the case sealing device of  FIG. 1  illustrating a work surface having an exit region lower than an entry region. 
       FIG. 3  is a top plan view of the case sealing device of  FIG. 1 . 
       FIG. 4  is a perspective view from a right or front side of a taping head assembly of the case sealing device of  FIG. 1 , illustrating a taping head and a taping head linkage. 
       FIG. 5  is a perspective view from a left or front side of the taping head assembly of the case sealing device of  FIG. 1  with the housing shown transparently in phantom. 
       FIG. 6  is a perspective view from a rear side of the taping head assembly of  FIG. 1 , illustrating a first stop and a second stop of the taping head linkage with the housing shown transparently in phantom. 
       FIG. 7  is a side view of a portion of the case sealing machine of  FIG. 1 , illustrating a carton to be taped and the taping head assembly, with the housing shown transparently in phantom, in a first or initial taping position. 
       FIG. 8  is a side view of the case sealing machine of  FIG. 1 , illustrating the carton and the taping head assembly, with the housing shown transparently in phantom, in a second taping position. 
       FIG. 9  is a side view of the case sealing machine of  FIG. 1 , illustrating the carton and the taping head assembly, with the housing shown transparently in phantom, in a third taping position. 
       FIG. 10  is a side view of the case sealing machine of  FIG. 1 , illustrating the carton and the taping head assembly, with the housing shown transparently in phantom, in a fourth or final taping position. 
       FIG. 11  is a perspective view from a front side of a second embodiment of a taping head assembly, with a housing shown transparently in phantom, for a case sealing machine including a curvilinear taping head guide. 
       FIG. 12  is a side view of the taping head assembly of  FIG. 11 , illustrating a taping head, a taping head linkage, and the curvilinear taping head guide. 
   

   DETAILED DESCRIPTION 
   With reference to  FIGS. 1-3 , a first embodiment of a case sealing machine  100  is shown. The sealing machine  100  includes a work surface  102  having a first elevation  102   a  corresponding with an entry region  104  and a second, lower elevation  102   b  corresponding with an exit region  106 . In addition, the sealing machine  100  includes a pair of generally parallel self-centering guides  108  mounted to the work surface  102  and disposed about a taping assembly  110 . 
   To aid in the discussion of the overall structure and function of the case sealing machine  100 , a brief recitation of operation is set forth. Generally, a case A (which has been at least partially erected) is received at the entry region  104  against the work surface  102  and between the centering guides  108 . As, the user of the machine  100  applies a moderate downward and forward pressure on the case A, the case A is driven through the centering guides  108 . The centering guides  108  center the case A with respect to the taping assembly  110 . Once the centering guides  108  have expanded to the appropriate width to accommodate the centered case A, the taping assembly  110  comes into contact with a first or forward wall surface B of the case A where a beginning of a strip of tape is adhered to the forward wall surface B. As the case A is pushed through the guides  108  and along the work surface  102 , the taping assembly  110  begins to pivot in a rearward fashion allowing the taping assembly  110  to move and adhere the tape down the forward wall B, round over a lower forward edge C of the box, and to a second or bottom wall surface D of the case A. Eventually, a rear edge E of the case A moves past the taping assembly  110 . At this point the case A is received into the exit region  106  which is at a lower elevation than the entry region  104 . As the user continues to urge the case A downward, the case A begins to drop to the second level where the tape is cut and an end portion of the tape is adhered to a third or rear wall surface F of the case A. To lessen user effort and long term fatigue, the centering guides and work surface can include a low friction coating or film (e.g. Teflon) thereby reducing the sliding friction between the machine and the case. 
   Each of the centering guides  108  can be operatively connected to the other via a linkage and/or a cable system such that both centering guides  108  move in equal yet opposite directions simultaneously. For example, a four bar linkage can be connected to the spindles of the centering guides. A plurality of pulleys connected are to the spindles and/or linkages while a cable follows a figure “8” pattern about the plurality of pulleys. As such, when one guide is pushed backward/outward against the resistance of a biasing force (e.g. a gas cylinder or spring), the other guide responds similarly but in the opposite direction and by the same amount. Since both guides retract or expand equally but in opposite directions, the case A will naturally take the path of least resistance traveling along the centerline of the taping assembly  110 . 
   With reference now to  FIGS. 4-6 , various perspective views of the taping assembly  110  are shown. Generally, the taping assembly  110  includes a frame or housing  112  for supporting a taping head  114  and a taping head linkage  116 . The housing  112  can be releasably secured to the work surface or table (e.g. via one or more clips, clevis pins, threaded fasteners, etc.) such that the taping assembly  110  can be removed with ease for periodic maintenance, adjusting, and/or replacement. The housing can include a first side wall  122 , a second side wall  124 , and a lower or lateral support member  126 . The taping head  114  includes a tape roll  128  for receiving the roll of adhesive tape G, an application roller  130  for applying the adhesive tape to the associated carton or case A ( FIG. 2 ), a wiper arm  132 , and a cutter  133 . The general purpose of the wiper arm  132  (discussed in greater detail below) is to press and smooth the trailing end portion of the tape against the rear wall surface F of the case once the tape has been cut by a cutter or cutting edge  133 . The taping head further includes a first support  134   a  plate, a second support plate  134   b , and a third support plate  134   c  which generally secure the tape roll  128  and the application roller  130  to the taping head linkage  116 . 
   With reference to  FIGS. 5 and 6 , the taping head linkage  116  of the taping head assembly  110  is shown in greater detail. The taping head linkage  116  includes a first arm or link  136  and a second arm or link  138 . The first arm  136  is rotatably secured by a first pin  140  between the first and second housing walls  122 , 124  and the second arm  138  is rotatably supported by the first arm  136  by a second pin  142  disposed at a distal end of the first arm  136 . The first arm  136  pivots about the first pin  140  and the second arm  138  pivots about the second pin  142 . The first arm and the second arm may also include respective first and second biasing members  144 ,  145 . In addition, the first, second, and third support plates  134   a - 134   c  secure the taping head  114  to the second arm  138 . 
   Generally, as a case is brought into contact with the application roller  130 , the taping head  114  pivots rearwardly about the first and second pins  140 , 142  and follows a curvilinear path defined by the individual rotation of each of the first and second arms  136 , 138 . By adjusting the biasing force or tension of the biasing members  144 ,  145 , the movement of the first and second arms  136 , 138  can be proscribed accordingly. By way of example only, if the biasing factors (e.g. ‘K’ factor or spring constant) of the first and second biasing members  144 ,  145  are equivalent, then the first arm  136  will deflect or pivot about the first pin  140  before the second arm  138  deflects or pivots about the second pin  142 . This occurs because the first arm  136  (if longer in length than the second arm  138 ) will develop a greater moment arm or torque. 
   With continued reference to  FIGS. 4-6 , the taping assembly  110  includes a variety of stops or limits, some of which are adjustable. In general, these stops define the forward/uppermost and rearward/lowermost positions of the taping head  114 . In particular, the first arm  136  includes a forward stop  146  and a rear stop  148 . As shown, both first arm stops  146 , 148  may include a dowel or pin having internally thread ends for securing the stops to the housing  112  of the assembly  110 . Furthermore, the housing  112  may include multiple lengthwise slots for adjusting the stops  146 , 148  in a forward or rearward direction to optimize the taping action of the assembly  110 . Similarly, the second arm  138  also includes a forward stop  150  and a rear stop  152 . The forward and rear stops  150 , 152  of the second arm  138  are attached to the first arm  136 . Thus, the overall travel of the second arm  138  can be adjusted with respect to the first arm  136 . For instance, and by way of example only, as the second arm  138  pivots upwards, a lower surface of the second arm  138  can eventually encounter the forward stop  150 . Similarly, as the second arm  138  pivots downwards it will eventually encounter or interfere with the rear stop  152 . However, unlike the forward stop  150 , the rear stop is adjustable by undoing a locking nut and threading the rear stop  152  into or out of the first arm  136 . By threading the rear stop  152  into the first arm  136 , the amount of rearward travel of the second arm  138  (and the taping head  114 ) is increased. Of course, any number of techniques may be used to adjust the range of motion of the first and second arms  136 , 138 . 
   Now with reference to  FIGS. 7-10 , the taping head assembly  110  is shown in various positions with respect to the associated case A and the work surface  102 . Specifically,  FIG. 7  illustrates the taping assembly  110  in a first or initial position. As illustrated, the taping head  114  is in an upper and forward-most position and the first and second arms  136 , 138  are fully against their respective forward stops. In the initial position, the leading end of the tape (with its adhesive facing outward) and/or the forward most portion of the application roller  130  contacts the forward wall surface B of the case A where the adhesive tape is first applied as it is driven into and over the taping assembly  110  ( FIG. 8 ). Prior to contacting the forward wall surface B, the tape may be held in contact with or adjacent to the application roller  130  due to a difference in electrostatic charge between the tape, application roller  130 , and/or a cross member  154  ( FIGS. 4 and 5 ). To enhance and/or prolong the electrostatic charge therebetween, the cross member  154  (FIGS.  4  and  5 ) may include an electrostatic retention member, coating, or other insulating material (e.g. glass, silk, rubber, acrylic, PVC, ABS, or any other plastic or polymer, etc.) having a triboelectric effect when brought into sliding or rolling contact with the cross member or the application roller  130 . By enhancing or prolonging the retention of the electrostatic charge, the likelihood that the cut end of the tape adjacent the application roller  130  will become detached, fold over onto itself, or onto another portion of the taping assembly  110  is greatly reduced. Thus, the uninterrupted service and overall reliability of the sealing machine can be improved. 
   With reference to  FIG. 8 , the taping assembly  110  is shown in a second or intermediate position. When the case is driven into and over the taping assembly  110 , the first arm  136  pivots rearwardly until it contacts the first arm rear stop  148  as the tape plays out from the roll G. At this point, the second arm  138  and the taping head  114  have not rotated about the second pivot  142  or moved with respect to the first arm  136 . Generally, by way of example only with respect to the instant embodiment, better taping action may occur if the first arm  136  rotates fully prior to the rotation of the second arm  138 . If the second arm  138  were to rotate first or concurrently with the first arm  136  it is possible that the case A might interfere with the support plates or frame of the taping head  114  making it more difficult for the user to push the case A through the machine. It should also be noted that the second position of the taping head  114  shown in  FIG. 8  generally represents the taping transition point between the forward wall surface B, the lower forward edge C, and the bottom wall surface D of the case A. 
   With reference to  FIG. 9 , a third intermediate position of the taping assembly  110  is shown. In the third position, the first arm  136  continues to rest against the first arm rear stop  148  while the second arm  138  rotates to its fully downward/rearward position and against the second arm rear stop  152  ( FIG. 6 ). In this orientation, the supporting plates or frame of the taping assembly will not interfere with the case as is it driven through the machine. With the second arm  138  fully rotated, the application roller  130  may protrude slightly above the generally horizontal work surface  102 . This protrusion ensures that the tape positively contacts the bottom wall surface D of the case A as it passes over the roller  130 . Depending on the amount of protrusion (which is a function of the rear stop setting for both first and second arms) this interference between the application roller  130  and the bottom wall surface D ( FIG. 2 ) of the case can produce a substantial normal force therebetween. 
   With respect to  FIG. 10 , the taping assembly  110  is shown in a final or rear wall taping or wiping down position. As the rear edge of the case A passes, the application roller  130 , the taping head  114  generally remains in the final or taping position because the adhesive tape has not yet been cut. After the rear edge E of the case A moves past the application roller  130  of the taping head  114 , the case A encounters a drop  160  from the first elevation  102   a  of the entry region  104  of the work surface  102  to the second elevation  102   b  of the exit region  106 . As the case A drops, the tape is pulled past or into contact with the cutter or cutting edge  133  and the wiper arm  132  (which is in contact with the bottom wall surface D) is deflected downward as the case A drops. As the wiper arm  132  is deflected downward, the cutter  133  is activated causing the cutting edge to protrude into the path of the tape thereby severing the tape. Once the tape is cut, the wiper arm  132  springs upward “wiping down” the trailing cut end portion of the tape against the rear wall surface of the case as the first and second biasing members  144 ,  145  ( FIG. 4 ) bias the first and second arms  136 , 138  into the first or initial position. 
   The wiper arm may include one or more layers each having various thicknesses and/or varying stiffness. The wiper can be stiffer at a base portion (near the taping head) and more flexible at a tip portion (farthest away from the taping head). A stiffer base portion ensures that the taper cutter will be activated as the case drops from the first level to the second level while a flexible tip portion ensures a good “wipe down” of the cut end portion of the tape. 
   It should be noted that both the “wiping down” action and the tape cutting are enhanced by the elevation change between the entry region and the exit region of the work surface. Furthermore, the transition between the entry region level and the exit region level can be accomplished in any number of ways. For example, a rounded or eased transition between the elevation of the entry region and the elevation of the exit region can be used as illustrated in the first embodiment. On the other hand, given a particular case design, size, or application other geometries including triangular, stepped, or curvilinear ramps may be used. Further still, the transition regions or ramps on either side of the taping assembly can be of dissimilar height so as to cause the case to tilt or drop unevenly thereby further enhancing the cutting action of the tape cutter. 
   With reference now to  FIGS. 11 and 12 , a second embodiment of a taping assembly  210  is shown. As with the first embodiment, the taping assembly  210  includes a frame or housing  212  for supporting a taping head  214  and a taping head linkage  216 . In addition, the frame  212  is secured to a generally planar work surface (e.g. a table). As shown in  FIG. 8 , the taping head  214  includes a tape roll  228  for receiving the roll of adhesive tape G, an application roller  230 , and a wiper arm  232 . As before, the taping head includes a wiper arm activated tape cutter  233 . Similar to the first embodiment, the taping head linkage  216  of the second embodiment also includes a first arm or link  236  and a second arm or link  238 . The second arm  238  includes a curvilinear taping head guide  240  rigidly secured thereto. In addition, a third arm or stationary link  242  (shown in dashed) is defined between a guide roller  244  and a primary pivot  245 . The first arm  236  pivots about the primary pivot  245  and the second arm  238  pivots about a secondary pivot  247  disposed at a distal end of the first arm  236 . 
   As mentioned previously, the curvilinear taping head guide  240  may be rigidly secured to the second arm  238  and can be in rolling contact with the guide roller  244 . As with the first embodiment, as a partially erected case or carton is brought into contact with the application roller  230 , the taping head  214  pivots rearwardly about the primary and secondary pivots  245 , 247 . However, the primary distinction with the second embodiment is that the taping head  214  must follow the proscribed curvilinear path as defined by the taping head guide  240  as it rolls downward along the guide roller  244 . As such, the first and second arms may move in independently or in concert as necessary to follow the proscribed curvilinear path. 
   In addition, the taping assembly  210  includes various adjustable limits or stops. As before, these stops define the uppermost and lowermost positions of the taping head  214 . In particular, the first arm  236  includes a forward stop  246  and a rear stop  248 . As shown, both first arm stops  246 , 248  consist of a threaded fastener which may be threaded in or out to adjust the overall travel of the first arm  236 . Also, the second arm  238  includes a forward stop  250  and a rear stop  252  which are the same or nearly identical to those of the first embodiment. The second arm forward and rear stops of the second arm could also involve a block slideably secured or attached to a rear surface of the first arm  236 . In either case, the overall travel of the second arm  238  can be adjusted with respect to the first arm  236 . In addition, a slot may be provided in the taping assembly housing  212  so that the guide roller  244  may be adjustable in a vertical and or horizontal direction. Adjusting the guide roller  244  would allow the curvilinear taping head guide  240  of the second arm to pivot more or less abruptly. In addition, the guide roller  244  (or cam follower) may be a rotating bearing element or a pin that travels along a low friction track or slot in either of the housing  212  or the curvilinear guide member  240 . 
   It should also be noted that the dual pivot design of the present invention allows for a much more compact design and for the option of varying the tension between the first arm and the second arm of the taping head linkage. If a single lever design were used, the overall length of the single lever or arm would have to be considerably longer than the present design. This would drastically increase the overall horizontal length of the machine. In addition, by providing separate tensioning or biasing members for the first and second arms, it is easier for the user to push a case through the machine rather than struggling to overcome the force needed to unroll the tape and to deflect the main biasing member. Naturally, the biasing members can take on any number of devices such as a spring, weight, pneumatic cylinder, or gas charged damper. 
   As noted previously, several adjustments can be made to alter the overall starting and ending positions of the taping assembly. In particular, the forward stop of the first arm should be adjusted so that the first arm is near vertical when the taping assembly is in the initial or starting position. This ensures that adhesive tape is not immediately under tension when the taping head begins to move rearward. In addition, the forward stop of the first arm should be adjusted so that the tape head is leaning forward at approximately a 10° angle to expose the maximum amount of tape to be rolled against the case and to help prevent any excessive amount of unrolled tape from becoming entangled. The rear stop of the first arm should be adjusted so that the support plates clear the work surface. And, the rear stop of the second arm should be adjusted so that the application roller is level with or slightly above the work surface. Furthermore, the stops may include preset positions or detents to accommodate a variety of taping conditions. The stops may also include bumpers fabricated from a soft or low durometer material, hydraulic dampers, and/or springs to reduce shock to the linkage arms and other components of the taping head assembly. Lastly, an unwind brake (provided on the tape roll to maintain positive tension) should be adjusted just tight enough to ensure a consistent cut by the tape cutter. 
   As is apparent from the above discussion, the present invention offers several advantages over known case sealing equipment. For one, the present invention provides a faster and easier technique for applying tape to a case as compared to a conventional hand taping gun. Rather than the user rotating the tape or hand taping gun about the case, the user instead pushes the case in a straight line along a generally flat work surface. This eliminates any user error in the proper application, alignment, and smoothing of the tape to the case. Furthermore, because pushing a case along a straight line is less stressful on a user&#39;s wrists as compared to rotating or manipulating a conventional hand taping gun, the risk of developing or aggravating carpel tunnel syndrome and/or other work related injuries is greatly reduced. In addition, the present invention requires no electricity as it is entirely human powered. A human or manually powered machine has the added benefit of making the device less expensive, more reliable, and simpler to use. 
   The exemplary embodiments have been described with reference to the preferred embodiments. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the exemplary embodiment be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.