Abstract:
The tubular banding applicator converts a flat tubular material into a cut length expanded tubular sleeve and mounts the sleeve circumferentially on a container. A driver moves a selected length of flat tubular material from a supply station, around a spreader, and into a hollow former having a retaining gate at an exit thereof. A cutter severs the selected length of tubular material from the supply station and a flow of air directed at a side of the flat tubular length assists in opening the sleeve. A conveyor carries a series of containers along a path to position each container in turn in alignment with the opened tubular sleeve. The driver moves a second selected length of flat tubular material from the supply into the former, thereby ejecting the first open sleeve from the former onto a container aligned below. The sleeve is subsequently caused to shrink to securely enwrap the container. The cut length may be either short in comparison to the height of the container and applied as a band between the container neck and a closure, or longer and applied to cover all or a portion of the container body.

Description:
RELATED APPLICATION 
     This application is a continuation-in-part of application Ser. No. 10/677,204 filed Oct. 2, 2003, now abandoned. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to the field of equipment and methods for applying tubular labels to containers, and more particularly to such labels that are supplied in flattened condition, opened prior to placement on a container and heat shrunk subsequent to being placed on the container. 
     BACKGROUND OF THE INVENTION 
     Traditionally, labels were attached by adhesive means to portions of the outer surface of containers to identify the enclosed products. This concept was particularly valid in the case of glass or plastic containers that could be more easily labeled than printed. More recently, labels have been used as surface ornamentation for most or all of the surface of the container, in addition to providing the necessary identification and information. Such full surface labels are often provided as a tube that is placed over the container and subsequently caused to shrink to snugly fit the container&#39;s contour. The tube is either made by tubular extrusion or by welding opposed longitudinal edges of an elongate sheet. The same advantage as noted above is obtained by printing the tubular label, rather than printing directly on the container, to decorate the container and identify the contents. Numerous products are being marketed today in containers with tubular labels. 
     Some containers are sealed by the application of a tubular band that covers all or a portion of the container neck and closure. Bands are generally shorter than labels. Bands serve as a tamper-evident indicator, thus improving product safety. 
     Tubular labels or bands can be supplied in cut lengths and fed from a magazine to the application machine, or supplied in continuous length on a roll, in which case the tubular supply is cut into pieces of a desired length in the applying machine. Tubular labels and bands are typically formed of polyvinyl chloride (PVC) or polyethylene (PE) resin. The process of applying a tubular label or band from a supply roll to a container involves the steps of drawing a length of tubular material from the supply, cutting the length of tubular material from the supply, reconfiguring the tubular material from a flat to an open cross section and placing the open cross section tubular material over the container in the selected position. The material may be substantially elastic and stretched to fit over the container, allowing the material to recover and to grip the container. Alternately, the material may be heat shrinkable, in which case the tube is placed loosely over the container and subsequently shrunk. The present invention is mainly directed to the application of labels and bands made of heat shrinkable material. 
     A machine for applying tubular labels to containers is disclosed in U.S. Pat. Nos. 5,305,578, No. 5,495,704 and No. 5,711,135 to Menayan. The Menayan apparatus utilizes a series of movably mounted suction cups for gripping successive cut bands. The suction cups are moved laterally to open the band from its flattened supply condition to an open application condition. A plunger is mounted angularly above the open band and activated to drive the leading band edge onto a leading edge of a container passing therebelow at the same time as an air blast is used to maintain the band in an open condition. 
     A further machine for performing such a handling process for a tubular band is the subject of U.S. Pat. No. 4,914,893 to Strub et al., entitled Large Size Container Banding Apparatus. The Strub et al. invention draws a length of tubular banding material from a supply roll of flat tube and expands the banding material to a substantially round cross section by pulling the banding material over an inserted wedge device which has rollers for smoothing edge creases that were formed in the previously flat tube. As the tubular band is cut to a desired length, a suction cup suspension means attaches to the band to maintain control during application of the band to the container closure. The band is subsequently heat shrunk to snugly surround the container closure and neck. 
     The present invention disclosed and claimed below provides a novel improvement over all known prior patents for the high speed expansion and mounting of short bands or full cover tubular labels to containers. 
     The present invention to be described below enables a large variety of band sizes to be applied to containers at a rapid rate and with relatively few moving machine parts. In this way, the present invention affords a simple, efficient band or label application apparatus and method. 
     SUMMARY OF THE INVENTION 
     The high speed banding applicator of the present invention provides a means to convert a flattened tubular supply material into a cut length expanded tubular band or label and to mount the cut length circumferentially onto a container. A drive station operates to advance a first selected length of flat tubular material from a supply station, around a spreader, and into a hollow cylindrical former. A gate is extended to temporarily prevent the tube from passing through the former. A cutter is activated to sever the selected length of opened tubular material from the supply to form a sleeve, and an air flow is directed at opposed sides of the cut sleeve to cause it to open radially. A conveyor transports a series of containers from a supply to a position in alignment with the axis of the former. The gate is retracted to allow the cut sleeve to pass out of the former. A second selected length of flat tubular material is advanced from the supply into the hollow former, thereby pushing the opened cut sleeve out of the former and onto the container aligned therewith. The sleeve is caused to shrink in a subsequent process so as to securely wrap around the container. The cut sleeve may be either a minor fraction of the height of the container and applied as a tamper-evident band over the container neck and closure, or a major fraction of the height of the container as a label. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention is best understood in conjunction with the accompanying drawing figures in which like elements are identified by similar reference numerals and wherein: 
         FIG. 1  is a schematic front elevation view of the tubular banding applicator of the invention. 
         FIG. 2  is a perspective view illustrating the transition of tubular material in a flaftened condition passing over a spreader and into a former, with the former partially cut away to expose a retractable plate adjacent thereto. 
         FIG. 3  is a perspective view of the former of the invention. 
         FIG. 4  is a cross-sectional view of the former taken in the direction of line  4 — 4  of FIG.  3 . 
         FIG. 5  is a cross-sectional view of the former taken in the direction of line  5 — 5  of FIG.  3 . 
         FIG. 6  is a top rear perspective view of the former with details of a gate and a constrictor plate. 
         FIGS. 7A-7D  illustrate a series of cross sectional top views of a tubular sleeve during the steps of being cut, opened, mounted on a container, and shrunk. 
         FIG. 8  is a flow chart showing the steps involved in the present invention banding applicator process. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The banding applicator apparatus  10  of the present invention is schematically illustrated in  FIG. 1 , comprising a machine for radially opening flattened tubular material to an expanded condition and placing a cut length of the opened tubular material circumferentially onto a container. The term “radially opening” indicates that the tube is expanded outwardly from a central axis of its flattened configuration to become two-dimensional in cross section, although not necessarily round; i.e. the opened tube may be shaped to match the cross section of the container on which the opened tube is to be mounted. As noted above, the present invention pertains to the mounting of a short band on the neck and closure portion of a container as well as to mounting a longer label to cover and decorate a major portion of the container&#39;s surface. 
     Referring now to  FIG. 1 , a quantity of flattened tubular banding material  14  is provided, preferably from a supply roll  12  that is rotatably mounted to enable tubular material  14  to be drawn through banding applicator  10  as needed. Tubular material  14  is drawn in the direction indicated by arrow A, passing over a spreader  20 , between a pair of idler rollers  22 ,  22 ′, and between a pair of drive rollers  24 ,  24 ′. Spreader  20 , to be described below, is placed inside tubular material  14  and supported on idler rollers  22 ,  22 ′ that are spaced from each other a distance sufficient to allow flattened tubular material  14  to pass therebetween and to maintain spreader  20  substantially in the position illustrated. Drive rollers  24 ,  24 ′ are intermittently driven in the direction indicated by arrows B by driver  28 , for example a stepper motor, as is known in the trade. In practice, only drive roller  24  is driven by driver  28 , and gearing between their respective shafts drives roller  24 ′. Alternatively, driver  28  may be another form of device, such as a motor and clutch combination, a linear motor, or a fluid-actuated cylinder. According to the preferred embodiment of the invention, driver  28  is actuated to extend a portion of tubular material  14  from supply  12 , and driver  28  is deactivated when a selected operator-preset length of tubular material  14  has been extended. The preset length may be determined by monitoring rotations of idler rollers  22 ,  22 ′ or by an encoder connected to driver  28 . In another embodiment, a sensor  26 , for example an optical detector, is connected to be in communication with driver  28  and to cause driver  28  to stop in response to detecting a registration mark printed on tubular material  14 . The tubular film for use in this second embodiment is printed with a series of such registration marks that are spaced apart from one another a distance equal to the desired length of the band to be cut. 
     Tubular material  14  next passes a cutter  30 , which in the preferred embodiments comprises a fixed blade  32 , a moving blade  34 , and a blade actuator  36 , as shown. Moving blade  34  is driven into and out of engagement with fixed blade  32  in the direction indicated by arrow C. Actuator  36  is, for example, a pneumatically actuated cylinder. Other types of cutter  30  may be utilized, as is applicable to the banding material employed. A forward portion of tubular material  14  is inserted into former  40  that is mounted below cutter  30 . 
     A gate  44  is mounted horizontally at a level adjacent to the lower surface of former  40  so as to be horizontally moveable. Gate  44  is extended and retracted by actuator  46 , which may be a fluid-operated cylinder or other form of linear motion driver. Alternatively, gate  44  may be configured to rotate in a horizontal plane to be placed into and out of the path of tubular material  14  by a controllable rotary device such as a servo motor. 
     Tubular material  14  is inserted into former  40 , and after being cut at a selected length, cut sleeve  14   a  opens radially for mounting onto a container  50  as container  50  is moved into position by conveyor  52 . Former  40  is described in detail below. When container  50  is in axial alignment below former  40 , gate  44  is retracted by actuator  46 . Opened sleeve  14   a  is expelled from former  40  by the advancement of a second length of tubular material  14  and mounted onto container  50  as container  50  is being moved below former  40  by container conveyor  52 . According to the preferred embodiment, conveyor  52  moves a series of containers  50  continuously without stopping as an expanded sleeve  14   a  is expelled from former  40  and placed on each container  50  in sequence. Conveyor  52  travels in a direction perpendicular to arrow A. Although the illustration of  FIG. 1  shows a sleeve  14   a  that is relatively short in length as is used to indicate to the consumer that container  50  has not previously been opened, and container  50  is of an arbitrary shape, decorative full length sleeve labels and different shaped containers  50  are understood to be in the scope of the present invention. 
     Referring now to  FIG. 2 , the flow of tubular material  14  passing around internal spreader  20  and into former  40  is illustrated in greater detail, with certain other machine components deleted for purposes of clarity. As it is coiled on and drawn from supply roll  12  (FIG.  1 ), flat tubular material  14  has a “layflat” dimension X. Dimension X is the width of flattened tubing, represented by the formula X=Πr, where “r” is the radius of the opened tube in circular cross section. Because tubular material  14  is coiled and stored under winding tension in the form of supply roll  12 , tubular material  14  forms and tends to retain a pair of creases C and C′ on opposite edges thereof. In  FIG. 2 , creases C, C′ are illustrated as lines composed of a long dash followed by two short dashes. Spreader  20  comprises an example of means for cross folding that is placed within tubular material  14  so that creases C, C′ that were located at opposed edges of tubular material  14  lie adjacent to one another; other cross folding means are usable. After passing over spreader  20 , creases C, C′ are repositioned to the center of tubular material  14  and pulled open. Spreader  20  has an upper plate  20   a  and a lower plate  20   c  that are connected to one another in spaced relation by a bar  20   b.  Upper plate  20   a  and lower plate  20   c  each reside in vertical planes that are mutually perpendicular. Upper plate  20   a  and lower plate  20   c  are substantially equal in width. Spreader  20  is placed within the interior of tubular banding material  14  so that creases C, C′ slidingly engage the vertical lateral edges of upper plate  20   a.  As tubular material  14  is drawn over spreader  20  and passes lower plate  20   c,  it is seen that lower plate  20   c  spreads tubular band  14  in a direction perpendicular to a plane between crease C and crease C′, thus causing the flat aspect of tubular material  14  to be reversed. During the step of spreading tubular material  14  transverse to creases C, C′, creases C, C′ remain oriented in a plane defined by the vertical edges of upper plate  20   a,  thereby passing creases C, C′ close to the center of lower plate  20   c . By making the width of lower plate  20   c  also similar to “layflat” width X of flat tubular material  14 , creases C, C′ are pulled fully open across lower plate  20   c , although creases C, C′ are not flattened or eradicated. The opposed vertical edges of lower plate  20 C create a pair of conforming edges E, E′ in tubular material  14 . Edges E, E′ are not typically creases in that they are not retained when tubular material  14  is released. Edges E, E′ are represented by uniform length dash lines. Although not shown in  FIG. 2  for reasons of clarity, idler rollers  22 ,  22 ′ and driven rollers  24 ,  24 ′ reside between spreader  20  and former  40  (see FIG.  1 ), with idler rollers  22 ,  22 ′ supporting spreader  20 . Tubular material  14  next passes into former  40 , shown in detail in  FIGS. 3 ,  4  and  5  and described below. Former  40  is mounted so that a pair of channels  62  are aligned parallel to lower plate  20   c  and a pair of guide grooves  64  are aligned parallel to upper plate  20   a.  As opened tubular material  14  passes into former  40 , creases C, C′ are maintained in alignment with guide grooves  64 , which serve to prevent tubular material  14  from twisting. 
     As tubular material  14  passes into former  40 , edges E, E′ enter respective channels  62  and creases C, C′ are adjacent to one another. Gate  44  is in its extended position below former  40  to prevent cut sleeve  14   a  from dropping. A supply of air is connected to an inlet  42  on either side of former  40 , each inlet  42  having a discharge end in a respective channel  62 . As cutter  30  ( FIG. 1 ) severs the extended portion of tubular material  14  at a level slightly above former  40 , the air flow through inlets  42  urges the cut sleeve to assume a cylindrical configuration in substantially cross-sectional conformity with the internal shape of cylindrical portion  56 . When a container  50  is about to be aligned below the opening in former  40 , gate  44  is retracted in the direction shown by arrow D and a further length of tubular material  14  is extended to discharge the cut sleeve  14   a  onto container  50 . While the preferred embodiment of the invention described relates to a former and container that are substantially round in cross section, other cylindrical cross sections, such as square or rectangular, are contemplated as would comport to the cross section of the container onto which tubular material  14  is to be mounted. 
     Referring now to  FIGS. 3 ,  4  and  5 , aspects of former  40  are described in greater detail. As indicated above,  FIG. 4  represents a cross section view of former  40  as taken in the direction of line  4 — 4  of FIG.  3  and  FIG. 5  in the direction of line  5 — 5  thereof. Former  40 , in one preferred embodiment, has a hollow conical mouth  58  extending from a larger entry end to a narrow end where it smoothly joins cylindrical portion  56 . In other embodiments of the invention, former  40  has no conical entry portion (see FIG.  6 ). Channels  62  reside in opposed side locations and are oriented substantially parallel to axis α of cylindrical portion  56 , and guide grooves  64  are formed substantially parallel to axis α in intermediate positions relative to channels  62 . Former  40  is preferably oriented so that guide grooves  64  are aligned with creases C, C′ and channels  62  are perpendicular thereto. 
     Former  40  is configured with an internal diameter Z that substantially conforms to the size of tubular material  14  in its opened condition. As noted in  FIG. 4 , dimension Y across the widest part of channels  64  is equal to or slightly larger than “layflat” dimension X (see  FIG. 2 ) of tubular material  14 . Dimension Z is substantially equal to the diameter of tubular banding material  14  in its fully opened round condition. Dimension L is slightly less than the length to which tubular material  14  is cut to form a sleeve for mounting onto a container  50 . Former  40  is preferably made of a material that is dimensionally stable and has a low surface friction, for example ultra high molecular weight polyethylene (UHMWPE). 
     Referring now to  FIG. 6 , and according to the description above, tubular material  14  is advanced in flattened condition through the opening in former  40  to a position above gate  44 , thus being positioned adjacent to a constrictor plate  68 , shown in  FIGS. 4 and 6 . Constrictor plate  68  is mounted in an exit chute  66  that is cut into a lower portion of former  40  at an exit side according to the flow direction of conveying containers, indicated by arrow F. Exit chute  66  allows a cut sleeve to move horizontally in the direction F with container  50  while cut sleeve  14   a  (shown in dashed lines) is dropping down onto a container  50  (see FIG.  1 ). Constrictor plate  68  is preferably formed at an inner edge thereof with a contour similar to the inner shape of former  40  and is positionable to impinge the central opening of former  40 . Therefore, as the air flow from inlets  42  urges cut sleeve  14   a  to open toward a round configuration, constrictor plate  68  imposes an elliptical restriction to the forward side of cut sleeve  14   a.  The somewhat elliptical cross section of cut sleeve  14   a  has been shown to improve the ease and reliability of mounting cut sleeve  14   a  onto a container  50 , improving the operational efficiency. 
     Cut sleeve  14   a  rests in position on extended gate  44 . When a container  50  is brought close to axial alignment with former  40 , actuator  46  ( FIG. 2 ) retracts gate  44 , allowing cut sleeve  14   a  to be discharged onto container  50 , whereupon gate  44  is again extended. Various plate designs and methods of moving may be substituted for the planar shape and linear motion of gate  44 , as will be apparent to those skilled in the art. 
       FIGS. 7A-7D  show a series of top cross sectional views of cut sleeve  14   a  in successive steps in the process of the invention.  FIG. 7A  shows tubular material  14  in flattened condition with creases C and C′ at opposed ends thereof.  FIG. 7B  shows tubular material  14  in cross folded condition with creases C and C′ adjacent one another and formed edges E and E′ at opposed ends as tubular material  14  is inserted into former  40 .  FIG. 7C  shows cut sleeve  14   a  in opened condition in former  40  and superimposed over a container  50  in position for mounting sleeve  14   a  thereupon.  FIG. 7D  shows sleeve  14   a  subsequent to mounting and shrinking onto container  50 . Whereas cross folded tubular material  14  prior to insertion into former  40  is wider than the diameter of opened sleeve  14   a  within former  40 , as a second length of tubular material  14  is advanced by drive rollers  24 ,  24 ′ the cut sleeve  14   a  residing within former  40  is discharged onto a container  50 . 
     The process of the present invention is controlled by a microprocessor (not shown), the steps of which are depicted in reference to the first embodiment in the form of a process chart in  FIG. 8 , to which reference is now made. The process is initiated in step  102 . Upon start-up of the apparatus, air flow is initiated in step  104 , and the container conveyor is activated in step  106  to transport containers from a container supply station (not shown) to banding applicator  10 . Tubular film  14  is cross folded in step  108  and a length of tubular film advanced in step  110 . The cross folded film is inserted into former  40  in step  112 . The process awaits a stop signal in step  114  and determines whether a registration mark, i.e. a mark showing the length of a piece of tubular material  14 , has been detected in step  116 . In step  118 , if a registration mark has been detected, the process goes to step  120 , stopping the extension of tubular material  14  (FIG.  1 ); if no registration mark has been detected, the process awaits a signal indicating the dispensed length is equal to the selected set length. Upon receipt of the length signal, the process goes to step  120  and stops the extension of tubular material  14 , the cut length being held in the former by the extended gate. Immediately upon stopping the extension of tubular material  14  at step  120 , and gate  44  is extended in step  121 . Tubular material  14  is cut at step  122 . The cut sleeve opens in step  124 , and, when an approaching container  50  is detected in step  125 , gate  44  is retracted in step  126 . A subsequent length of tubular material  14  is advanced into the former to expel the first cut sleeve  14   a  onto a container  50  passing therebelow in step  128 . At this stage, the first sleeve  14   a  is mounted onto a container  50  and a second length of tubular material  14  is being inserted into former  40 . The process is repeated by returning to step  114  to await a stop signal. 
     In summary, the present invention provides an apparatus for applying a band from a continuous supply of flattened tubular material to each one in a series of containers, the apparatus comprising:
         a. a supply of tubular film material in flattened condition;   b. a film tube spreader positioned within the tubular film material downstream of the supply;   c. means positioned downstream of the film tube spreader for advancing a selected length of the tubular material;   d. a cutter positioned downstream of the advancing means;   e. a former positioned downstream of the cutter for receiving the flat tubular film and radially opening the tubular film;   f. the former having a pair of guide grooves positioned to receive a pair of creases on opposed edges of the flat tubular film;   g. the former further having means to urge the cut flat film to open and form a sleeve;   h. retention means for holding the cut length sleeve in the former;   i. means for positioning each one of a series of containers sequentially in axial alignment with the former so as to circumferentially receive an open sleeve from the former.       

     While the description above discloses a preferred embodiment of the present invention, it is contemplated that numerous variations and modifications of the invention are possible and are considered to be within the scope of the claims to follow.