Abstract:
A label applicator system provides for high speed, accurate label transfer from a web to items moving on an item transport along a path relative to the system. The items, such as bottles, have a contoured surface. The applicator includes a supply reel for supplying labels on a web and a take-up for taking up the web after transfer of the label. A drive roller moves the web through the applicator system. The system includes a web positioning assembly and a movable label applicator head. A contour sensor senses the bottle contour and develops a profile for the head to follow to apply the labels to the bottles. The supply, take-up and the drive are operably engaged with one another to maintain a relatively constant tension in the web. The web positioning assembly is configured to advance and retract the web to accommodate a pitch difference between the bottles in the bottle transport and the labels on the web and to accommodate movement of the decorating head toward and away from the bottles in the bottle transport.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates to a decorating or graphic transfer system. More particularly, the present invention pertains to a high speed decorating system for label or graphic transfer that accommodates transfer to contoured surfaces and accommodates differences in pitch between the graphic and the receiving surface. 
         [0002]    Containers, and particularly bottles, are often decorated with indicia, logos and the like, as well as information such as food stuffs ingredients and nutritional information. The decoration can be provided as a label that is, for example, glued or adhered to the bottle, or as printing applied directly to the bottle. 
         [0003]    As to labeling the bottles, this can be done in a number of ways. For example, adhesives can be used to adhere the label (e.g., pressure sensitive labels) directly to the bottle, such as a film-like wrap around label commonly used on 2 liter soda-pop bottles. Other methods include adhering a full, sleeve-like label both to itself and to the bottle. Another method includes wax transfer labels, in which a label is transferred from a web having a wax release layer. The wax transfer labels provide the least degradation over time. In addition, unlike pressure sensitive labels, the wax transfer label does not have to be removed prior to recycling, which is a consideration that is of increasing importance. 
         [0004]    Label applicator machines for transferring labels from the carrier web to the bottles have become complex. Due to the increasing demand on manufacturing efficiencies and the attendant costs, many such machines are designed to provide increased throughput with lower labor costs. 
         [0005]    In addition, the complexity of bottle profiles has also placed a high demand on the operating equipment. In order to assure that the label properly transfers to the bottle, the bottle contour must be precisely known, and the indexing of the bottle vis-à-vis the label (e.g., an accommodation of the label and bottle pitches) must be made. These steps, however, are found to be difficult to carry out and time intensive. 
         [0006]    Accordingly, there is a need for a high speed wax transfer decorating system that accurately maps the profile of a bottle and adjusts the label position and the label web speed to properly apply the label to the bottle. Desirably, such a system also accounts for the change in supply and take-up spool diameters to monitor the quantity of labels remaining on the web to provide indication that the label supply is running low. 
       BRIEF SUMMARY OF THE INVENTION 
       [0007]    A label applicator system provides for high speed, accurate label transfer from a web to items moving on an item transport along a path relative to the system. The items, such as bottles, have a contoured surface. 
         [0008]    The present system accurately maps the profile of the bottle and adjusts the label position as well as the label web speed to properly apply the label to the bottle. The system also accounts for the change in supply and take-up spool diameters as the label web moves through the applicator and the labels are transferred to the bottles (as the labels are used). 
         [0009]    The applicator includes a supply, such as a reel for supplying the web (with the labels on the web) and a take-up for taking up the web after transfer of the label from the web to the bottle. A drive element such as a roller moves the web through the applicator system. 
         [0010]    The application includes a web positioning assembly and a movable label applicator head. A contour sensor senses the bottle contour and develops a profile for the head to follow to apply the labels to the bottles. The overall system is controlled by a control system. 
         [0011]    The supply, the take-up and the drive element are operably engaged with one another to maintain a relatively constant tension in the web. The web positioning assembly is configured to advance and retract the web to accommodate a pitch difference between the bottles in the bottle transport and the labels on the web. The web positioned assembly also advances and retracts to accommodate movement of the decorating head toward and away from the bottles in the bottle transport. 
         [0012]    These and other features and advantages of the present invention will be apparent from the following detailed description, in conjunction with the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0013]    The benefits and advantages of the present invention will become more readily apparent to those of ordinary skill in the relevant art after reviewing the following detailed description and accompanying drawings, wherein: 
           [0014]      FIG. 1  is an illustration of a high speed decorating system embodying the principles of the present invention; 
           [0015]      FIG. 2  is an exemplary bottle profile representing the surface contour of a typical bottle; 
           [0016]      FIG. 3  is a plan view of a portion of an exemplary web with labels there showing the label pitch; 
           [0017]      FIGS. 4 and 5  are perspective views of an embodiment of the high speed decorating system with two bottles mounted on a conveyor; 
           [0018]      FIG. 6  is a partial perspective view of applicator system illustrating a product inflation subsystem; and 
           [0019]      FIG. 7  is a top view of the applicator system of  FIG. 6  showing a mirror image applicator or simultaneously applying labels to both sides of the bottles. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0020]    While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred embodiment with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiment illustrated. 
         [0021]    It should be further understood that the title of this section of this specification, namely, “Detailed Description Of The Invention”, relates to a requirement of the United States Patent Office, and does not imply, nor should be inferred to limit the subject matter disclosed herein. 
         [0022]    Referring now to the figures and in particular, to  FIG. 1  there is shown an illustration of a high speed wax transfer system  10  embodying the principles of the present invention. The transfer system  10  includes a web transport system illustrated generally at  11 , mounted to a frame  12  having a payout reel  14 , from which a web W having labels L thereon are fed and a take-up reel  16  that takes up the web W after transfer of the labels L. As will be appreciated by those skilled in the art, generally, labels L are presented on a waxed web W that is wound around the payout reel  14 , introduced to a decorating or applicator head  18  at which the labels L are separated from the web W and transferred to a product P such as a bottle, and the label-less web W is then rewound onto the take-up reel  16  for later processing. 
         [0023]    The web W is fed from the payout reel  14  over a first roller  20  and is redirected to a payout analog dancer arm  22 , over which the web W is again redirected. As will be discussed in detail below, the payout dancer arm  22 , along with a take-up analog dancer arm  24 , and the payout and take-up reel  14 ,  16  movements serve to maintain a constant tension on the web W as it moves through the applicator system  10  to orderly and accurately position labels L for transfer to the products P. 
         [0024]    Moving along the web W path, from the payout dancer arm  22 , the web W passes over one side  26   a  of a reciprocating servo web positioner  26 , around additional (idler) rollers  28  and on to a heating element  30 . The back side of the web W is heated and passes over the reciprocating servo decorating head  18  at which the label L is transferred from the web W onto the product P. A heater block indicated generally at  32  at the decorating head  18  (in the support  34  for the head  18 ) further heats the web W just prior to label L transfer. The label-less web W passes over additional idler rollers  36  and onto an opposing end  26   b  of the web positioner  26 . 
         [0025]    Following the web positioner  26 , the web W passes over additional idler rollers  38  and over a servo-driven web feed roller  40  after which the web W traverses over the take-up dancer arm  24  and onto the take-up reel  16 . The servo-driven web feed roller  40  provides the drive to move the web W through the system  10 , while the payout and take up reels  14 ,  16  are intended to supply and take up the web W and to provide a general or gross tension in the web W. 
         [0026]    Both the payout and take-up reels  14 ,  16  are also servo driven, mounted to shafts  42 ,  44  for rotation. The payout and take-up dancer arms  22 ,  24  are analog (e.g., linear) movement elements that move along respective paths that are about tangential to their respective reels  14 ,  16 . The dancer arms  22 ,  24  are both biased (sprung, as indicated at  58 ) to maintain tension on the web W as it is fed from the payout reel  14  and as it is wound onto the take-up reel  16 . 
         [0027]    A laser sensor (head)  46  maps the profile or contour of the product P as it passes (or just prior to passing) the head  18 . This is carried our for each “new” product profile. The laser  46  samples points from a start point (operator designated) along the product profile to an end point. A controller  48  includes code or commands such that the start and end points are mathematically blended to provide a smooth transition (rather than a sharp or step function) at the start and end of label L application. The mapping is a “learned” process, and a sample contour plot is illustrated in  FIG. 2 . 
         [0028]    As the product (bottle) P is conveyed passed the laser sensor head  46  and the decorating head  18  (discussed below), it is inflated with compressed air. Inflating the products during label transfer is carried out to provide a resistance or back-pressure against the decorating head  18  pressing the label L to the product P and serves to maintain the intended or designed profile of the product P (e.g., product P shape) during label L transfer. Inflating during profile mapping assures that the mapped profile matches the profile of the product P during application. 
         [0029]    Referring to  FIG. 6 , inflation is carried out at an inflation substation  76 , by applying a moving cup seal  78  to an opening in the product (the open top  0  of the illustrated bottle) and introducing a predetermined quantity of compressed air into the product P through the cup seal  78 . As the product P moves beyond the applicator  10 , the cup seal  78  is removed from the product P thus allowing the product P to return to atmospheric pressure. The inflation pressure in the product is monitored to within about 0.1 psi to assure adequate inflation and to prevent over-inflation. 
         [0030]    The decorating head  18  is also a servo-driven  50  element that reciprocates toward and away (as indicated by the double headed arrow at  52 ) from the product path  54 , to move the web W and label L into contact with the product P in accordance with the mapping scheme developed by the laser head  46  and controller  48 . Essentially, the mapping scheme (e.g., the laser taught contour) functions as an electronic cam to move the head  18  (and thus the web W and label L) to follow the product P profile. The cam profile is repeated once per product repeat pitch. The repeat pitch P P  (i.e., the distance between the same point on two adjacent products P) is set by an operator and in a present transfer system  10  is variable between about 3 inches and about 9 inches; however, other repeat pitches are contemplated. When the repeat pitch is established, the head  18  is set to follow the cam profile at each repeat pitch interval. 
         [0031]    The decorating head servo  50  is a linear movement element. It provides a high velocity, low inertia motion response to accurately follow the cam profile (or product contour) without exerting an over-pressure on the product P. 
         [0032]    The head  18  includes a roller  56  (with the heater within the head support  34 ) to facilitate label L transfer. The web W is moved over the roller  56  at a speed that is matched to the product P movement during application. Between label L applications, the web W can change speed (increase or decrease) to properly position a next label for application to a next product, according to the product repeat pitch P P  and the label pitch L P  (the pitch of the labels L on the web W). 
         [0033]    The decorating head roller  56  includes a matrix of holes and grooves (not shown) formed on its heated face, prior to the label transfer point. A vacuum is drawn at the face (again, prior to the transfer point) to the heated surface to assure fast and thorough heating of the label L. Immediately following transfer, the web W is cooled by passing the web W over a chiller plate  57  to cool the wax that remains on the web W. The chiller  57  is supplied with chilled air to cool the molten wax to prevent wax build-up on the adjacent surfaces (e.g., roller  36 ). 
         [0034]    The present system  10  includes a number of features that enhance label L application speed and placement accuracy. First is the web transport system  11  which is configured to accurately move the web W through the applicator system  10  maintaining the web W at a fairly constant tension. The servo web feed roller  40  provides the motive force to move the web W through the system and the dancer arms  22 ,  24  are biased (as by springs  58 ) slides each having an idler roller  60 ,  62  at the end thereof over which the web W passes. The dancer arms  22 ,  24  provide for proper tension of the web W and are used to monitor the quantity of labels/web on the payout and take-up reels,  14 ,  16 , respectively. 
         [0035]    The position of each arm  22 ,  24  is monitored by a scaled analog signal transmitted from a transducer  64 ,  66  mounted to the slide  22 ,  24 . In that the web W is looped over the rollers  60 ,  62 , a one inch (linear) movement of either arm  22 ,  24  translates to a 2 inch linear movement of the web W. This is then compared to rotational movement of the reel  14 ,  16  (or conversely, how far the arm  22 ,  24 , moves compared to a predetermined number, e.g., one, rotation of the reel  14 ,  16 ), which is then used to determine the circumference of the reel  14 ,  16  which corresponds to the quantity of labels/web on the reel  14 ,  16 . Accordingly, the quantity of web W (an thus labels L) that remain on the payout reel  14  is know from the initial diameter, the rotational movement and the movement of the slide  22 ,  24 . When a new roll of labels L is installed on the applicator system  10  the initial ratios are calculated by rotating the payout reel  14  (shaft  42 ) a predetermined distance until a target distance of the dancer arm  22  is detected. The rotation of the reel  14  (in degrees of rotation) that is needed to achieve the target arm  22  movement is calculated as a percentage of 360 degrees and this percentage is used to determine the initial circumference of the reel  14 . By example, if 45 degrees of rotation is needed to produce a 3 inch movement of the dancer arm  22  (which is 6 inches of web W movement), the calculation of 360/45 yields a value of 8, which is then multiplied by the web W movement (6 inches) to yield an initial reel  14  circumference of 48 inches. 
         [0036]    The next feature is the servo web positioner assembly  26  which defines a web path that is symmetrical before the decorating head  18  (as indicated generally by the arrow at  68 ) and after the decorating head (indicated generally at  70 ), e.g., a head approach path  68  which is between the payout reel  14  and the head  18  and an egress path  70  that is between the head  18  and the take-up reel  16 . 
         [0037]    The assembly includes a single servo actuator  26 , which is a linear slide, having rollers  72   a,b  at the opposite ends  26   a,b , with the roller  72   a  on one end  26   a  in the approach path  68  and the roller  72   b  on the opposing end  26   b  in the egress path  70 . The egress path side  26   b  is nearer to the product path  54 . In that the approach and egress paths  68 ,  70  are identical, movement of the web W is linear relative to the movement of the servo actuator  26 . 
         [0038]    As a result, as the web positioner servo  26  moves toward or away from the product path  54 , the web W movement is two times that of the actuator  26 , as long as the web W is held taut between the payout and take-up reels  14 ,  16 . Web W movement is two times that of the servo  26  movement because the web W is looped around or over the rollers  72   a,b . For example, a one inch movement of the actuator  26  away from the product path  54  (or into the approach path  68 ) results in a two inch linear forward movement (or advance) of the web W. 
         [0039]    This movement of the web positioner servo  26  serves to accommodate two variables in the system, namely, the differences in the label pitch L P  and product pitch P P  and the differences in web W speed and product P speed. Where, for example product P speed is 360 inches per minute, labels L are applied at a rate of one (1) per second and the label pitch L P  is 5 inches. If the product pitch P P  is 6 inches, the web W moves at a speed of 300 inches per minute to account for the lesser label pitch L P . 
         [0040]    The web positioner servo  26  matches the web W speed to the product P speed during application of the label L to the product P. That is, the positioner servo  26  moves to “increase” the speed of the web W to a desired speed to provide a smooth transfer of the label L from the web W to the product P. 
         [0041]    The web positioner servo  26  performs a cam profile once per product pitch P P  to account for the pitch (P P −L P ) differences. In between labels L (when the labels L are on a lesser pitch than the products), the cam profile jumps the positioner servo  26  to move the next label into position for transfer to the next product. In addition, using the web positioner servo  26 , the web W can be run at a slightly faster or slower rate to control label L stretch during the application process. 
         [0042]    It will also be appreciated that as the decorating head  18  reciprocates, it too advances and retracts the web W from its ordinary movement and speed. This movement of the web W must also be accommodated or accounted for in order to both position the label L properly and to match the web W speed with the product P speed. The web positioner servo  26  also serves to accommodate web W movement due to decorating head  18  movement to maintain the label L properly positioned for transfer. 
         [0043]    In order to compensate for error in label L positioning as the decorating head  18  follows the product P contour, the positioner servo  26  and the decorating head roller  56  are geared to one another so that the position of the web W resulting from movement of the head  18  is compensated for by the positioner servo  26 . For example, as the decorating head  18  moves toward the product P (following the profile), the positioner servo  26  moves away from the product path  54  an equal amount to prevent skewing of the label L. 
         [0044]    Although the web feed roller  40  rotates at a relatively constant rate to move the web W through the applicator system  10  at a constant rate, it will be appreciated that the web W speed may not always be able to be maintained at a constant rate. Accordingly, a sensor eye  74  is mounted at the roller  40  to sense the presence or absence (or the indexing) of a registration mark R formed on the labels L or on the web W. The sensor eye  74  can be used (through the controller  48 ) to adjust the speed of the feed roller  40  to achieve a desired web W speed. 
         [0045]      FIGS. 6 and 7  illustrate a labeling line that is configured for simultaneous two-sided application. The line includes labeling systems  10 ,  10 ′ in mirror image relation to one another. In this manner labels can be applied to both sides of the product simultaneously and can make use of a single inflation subsystem. 
         [0046]    All patents referred to herein, are hereby incorporated herein by reference, whether or not specifically done so within the text of this disclosure. 
         [0047]    In the present disclosure, the words “a” or “an” are to be taken to include both the singular and the plural. Conversely, any reference to plural items shall, where appropriate, include the singular. 
         [0048]    From the foregoing it will be observed that numerous modifications and variations can be effectuated without departing from the true spirit and scope of the novel concepts of the present invention. It is to be understood that no limitation with respect to the specific embodiments illustrated is intended or should be inferred. The disclosure is intended to cover all such modifications as fall within the scope of the invention.