Patent Publication Number: US-2020283179-A1

Title: Variable pitch starwheel for container carrier applicating machine

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Application Ser. No. 62/813,397, filed on 4 Mar. 2019. This U.S. Provisional Application is hereby incorporated by reference herein in its entirety and is made a part hereof, including but not limited to those portions which specifically appear hereinafter. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     This invention relates to a system for transferring containers within a carrier applicating machine. 
     Description of Prior Art 
     Container carriers connect two or more containers into a sturdy unitized package or “multipack” of containers. Carriers are generally planar arrays of rings, sometimes referred to as “six-pack carriers,” typically formed from a thermoplastic sheet material. Carriers are applied to containers of various sizes and shapes. 
     The unitized containers are generally randomly oriented so that each container is positioned in a different rotational orientation within the carrier. This random orientation results in inconsistencies related to displaying the package, particularly the container&#39;s trademark and graphics. In addition, it is often preferable to ensure that UPC labels on the respective containers are oriented correctly, either facing inward or outward. 
     According to one method know in the art, individual containers are rotated, either manually or mechanically, into a preferred orientation after packaging randomly oriented containers in the container carrier. Rotation of the containers once the containers are engaged within the container carrier may destroy the integrity of the container carrier through excessive torque applied to the respective thermoplastic rings within the container carrier. Alternatively, rotation of the containers may be impossible once the containers are sealed within shrink-wrapped or similar packages known to those having ordinary skill in the art. 
     Existing orientation systems enable containers to be rotated into a desired rotational position and then engaged with the container carrier to fix the desired rotational position within the package. However, difficulties arise between orientation and transfer to the container carrier, particularly in maintaining the desired orientation as containers travel between the orienter and engagement within the container carrier. 
     Therefore, a need exists for a system and method of transferring oriented containers, of all sizes, to a container carrier and a resulting package. 
     SUMMARY OF THE INVENTION 
     According to one preferred embodiment of this invention, a system for packaging containers preferably cooperates with an inlet conveyor and a jaw drum. An orienter preferably accepts a plurality of containers from the inlet conveyor and singularizes each container and then rotates each container into a desired rotational position for presentation to a starwheel or “transfer device.” 
     The starwheel preferably includes a central wheel and a corresponding radial position cam and angle position cam. A plurality of can grippers are preferably arranged around the central wheel. Each can gripper preferably includes a radial follower that engages with the radial position cam and an angle follower that engages with the angle position cam. 
     Each cam gripper therefore includes a radial follower that moves with the radial position cam to adjust a radial position of the can gripper as it rotates around the central wheel and an angle follower that moves with the angle position cam to adjust an angular position of the can gripper as it rotates around the central wheel. In this manner, containers can be provided to a transfer device at a first pitch and a first centerline and transferred in a fixed angular position to a second pitch and a second centerline. This permits the subject system to orient and transfer containers from a continuous input to a desired position at the jaw drum for unitization. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above-mentioned and other features and objects of this invention will be better understood from the following detailed description taken in conjunction with the drawings wherein: 
         FIG. 1  is a top view of a packaging machine according to one preferred embodiment of this invention; 
         FIG. 2  is a side perspective view of the packaging machine shown in  FIG. 1 ; 
         FIG. 3  is a partial cutaway top view of a variable pitch starwheel according to one preferred embodiment of this invention; 
         FIG. 4  is a top view of a variable pitch starwheel according to one preferred embodiment of this invention; 
         FIG. 5  is a top perspective view of a gripper according to one preferred embodiment of this invention; 
         FIG. 6  is a side view of a variable pitch starwheel at a transfer point from a container orienter; and 
         FIG. 7  is a side view of the variable pitch starswheel shown in  FIG. 6  at a transfer point to an applicating drum. 
     
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
       FIGS. 1-2  show a packaging machine  10  for unitizing containers  20  in a container carrier  30  and  FIGS. 3-7  more particularly show a variable pitch starwheel  60  for transfer of containers  20  within the packaging machine  10 . The variable pitch starwheel  60  as described is preferably used in connection with traditional packaging machines for applying a generally continuous string of container carrier  30  to a plurality of containers  20 . Container carriers  30  may be, though not necessarily, formed from an elastic thermoplastic material having a plurality of container receiving openings, each for engaging a container  20 . Alternatively, other packaging known to those having ordinary skill in the art, such as paperboard, shrinkwrap, cartoning, gluing and/or other unitization and/or joining methods may be used in connection with the system. 
     In one example of a packaging machine according to the present invention, as shown in  FIGS. 1 and 2 , an inlet conveyor  40  feeds the plurality of containers  20  into packaging machine  10  having an orienter  50 , a starwheel  60  and a jaw drum  70 . The jaw drum  70  preferably spreads the container carrier  30  and engages each container  20  with the container receiving opening. When the container carrier  30  is stripped off the jaw drum  70 , the container carrier  30  elastically retracts around each container  20  and tightly engages the plurality of containers  20 . Absent the orienter  50 , or a similar system for orienting containers, each container  20  is rotationally positioned in a generally random orientation. In alternative examples of such traditional packaging machines, the inlet conveyor  40  feeds the plurality of containers  20  into paperboard carriers that are glued or otherwise sealed or into plastic sleeves that are shrunk wrapped or otherwise sealed. 
     Container carriers  30  preferably moves through the packaging machine  10  from a reel stand where carriers  30  are dispersed in a continuous string of carrier stock from either reels or large boxes of carrier stock and ultimately to packages where each carrier is separated into a unitized package, each package containing a plurality of uniform containers. A typical configuration for a package is a “six-pack” containing two longitudinal rows of containers in three transverse ranks. Additional desired packages such as four-packs, eight packs and twelve packs may be unitized using machine  10  according to this invention, and such additional sizes of packages are limited only by the consumer market for such additional sizes. 
     Carrier  30  (and carrier stock) is preferably constructed from a flexible plastic sheet, such as low-density polyethylene or a blend containing similar desirable properties. The flexible plastic sheet is punched or otherwise formed into a plurality of container receiving apertures aligned in transverse ranks and at least two longitudinal rows to form a continuous sheet of carriers. 
     Accordingly, a plurality of containers is provided from the inlet conveyor  40  and ultimately to the jaw drum  70  for application of the container carriers  30  to containers  20 . As described, the jaw drum  70  may be positioned with respect to the inlet conveyor  40  to accept the plurality of containers  20 . The carrier  30  proceeds from a reel stand, carton and/or infeed to the jaw drum  70 , particularly to a plurality of jaw pairs located radially about the jaw drum  70 . The jaw drum  70  preferably comprises a cylindrical member rotatable about a horizontal axis which transports the carrier  30  to the plurality of containers  20  which flow through the jaw drum  70 . As the jaw pairs move with the rotation of jaw drum  70 , container receiving apertures within the carrier  30  stretch to accommodate a container  20 . The carrier  30  in a stretched condition is positioned over a plurality of containers so that each container receiving aperture engages with one container. Upon engagement with the containers  20 , the carrier  30  is released from the respective jaw pair and grips a perimeter of container. 
     An output conveyor  80  preferably conveys the containers  20  longitudinally from the jaw drum  70  after the carrier  30  has been applied. After the carrier  30  is stripped from the jaw drum  70 , a continuous string of unitized containers proceeds along the output conveyor  80  and through a cutoff device  90 . According to a preferred embodiment of this invention, the cutoff device  90  is adjustable and/or replaceable with minimal use of tools to divide packages into any number of desired sizes. 
     The system according to one preferred embodiment of this invention preferably cooperates with the inlet conveyor  40  and the jaw drum  70 . An orienter  50  as described preferably accepts a plurality of containers  20  from the inlet conveyor  40 . The orienter  50  preferably singularizes each container  20  and then rotates each container  20  into a desired rotational position to the starwheel  60 . According to one preferred embodiment of this invention, and as shown in  FIGS. 1 and 2 , the inlet conveyor  40  preferably branches into two single file rows of containers  20  each with their own orienter  50  and starwheel  60  before the two rows merge back together at the jaw drum  70 . 
     The plurality of containers  20  from inlet conveyor  40  are preferably fed into the orienter  50 , as described. The orienter  50  is preferably generally round with a plurality of radially spaced recesses formed within a perimeter, each recess configured to accept one container  20  of the plurality of containers  20 . Therefore, the orienter  50  preferably initiates or maintains singularization of the plurality of containers  20  into separate recesses. 
     According, to one preferred embodiment of this invention, one or more recesses of the orienter  50  further includes a chuck for engaging one end of the container  20 . As best shown in  FIG. 6 , the chuck preferably comprises a flexible contact to maintain pressure against the container  20 . Alternatively, a sleeve having an internal cavity may be formed to engage an end of the container  20  in flush and/or mating contact. Flush, and preferably mating, contact is formed between the chuck and the container so that the container  20  rotates in synchronization with the chuck. According to one preferred embodiment of this invention, each recess further includes a pressure plate securing an opposite end of the container  20  from the chuck. 
     As a result, a container, such as a can, is firmly engaged between the chuck and the pressure plate. The pressure plate preferably, though not necessarily, comprises a generally flat, smooth surface that permits rotation of a bottom of the container. A motor is preferably mechanically coupled to the chuck to rotate the container. At least one sensor, such as a photocell, may be additionally connected with respect to the orienter  50  for locating the oriented position of container  20  and stopping the rotation of the container  20 . 
     As a result, the motor fixes the orientation of the container  20  within the respective position in the orienter  50 . Accordingly, the orienter  50  individually and independently places an oriented container  20  at a pickup location for the starwheel  60 . 
     As shown in  FIGS. 1-7 , the starwheel  60  is preferably connected with respect to the orienter  50 . The starwheel  60  transfers an oriented container  20  in a fixed rotational position from the orienter  50  to the jaw drum  70 . The starwheel  60  preferably grips the oriented container  20  with sufficient force to prevent rotation as the oriented container  20  slides along a stationary floor or against a stationary wall of the system. 
     As shown in the figures, a system according to this invention preferably comprises two orienters  50  and two starwheels  60  which together result in the orientation and transfer of two rows of containers  20 . This arrangement speeds up the packaging process and also cooperates with typical packaging machines  10  that accept two rows of containers  20 . 
     The starwheel  60  also referred to herein as the “transfer device” is best shown in  FIGS. 3-7  and preferably includes a central wheel  100 . A radial position cam  110  is preferably positioned relative to the central wheel  100 . Likewise, an angle position cam  120  is preferably positioned relative to the central wheel  100 . 
     As shown in  FIGS. 3 and 4 , a plurality of can grippers  130  are arranged around the central wheel  100 . Although the term “can” is used in association with the term “can gripper  130 ,” it is understood that bottles or other containers  20  may be engageable with the starwheel  60  and/or the can grippers  130  as described. The can grippers  130  are preferably configured to accommodate containers having diameters between approximately 2 inches and approximately 3 inches. 
     As best shown in  FIG. 5 , each can gripper  130  preferably includes a radial follower  140  that engages with the radial position cam  110  and an angle follower  150  that engages with the angle position cam  120 . Each cam gripper therefore includes a radial follower  140  that moves with the radial position cam  110  to adjust a radial position of the can gripper  130  as it rotates around the central wheel  100  and an angle follower  150  that moves with the angle position cam  120  to adjust an angular position of the can gripper  130  as it rotates around the central wheel  100 . As shown in  FIG. 4 , a radial distance from a center of the center wheel  100  changes as each can gripper  130  rotates around the center wheel  100 . Likewise, a spacing between each adjacent can gripper  130  changes as each can gripper  130  rotates around the center wheel  100 . 
     As shown in  FIG. 4 , a pickup location  200  includes a first pitch and a first centerline of the respective can gripper  130  and a dropoff location.  210  includes a second pitch and a second centerline of the respective can gripper  130 . According to a preferred embodiment of the invention, each adjacent can gripper  130  is in movement relative to each other adjacent can gripper  130  between the pickup location  200  and the dropoff location  210  and is generally static between each adjacent can gripper  130  during travel from the dropoff location  210  and the pickup location  200 . 
     One or more links  135  are preferably positioned between the radial follower  140  and the angle follower  150  to permit pivotal movement of the can gripper  130  as it traces around the central wheel  100 . 
     As further shown in  FIG. 5 , each can gripper  130  may further include a gripper head  160  positioned at one end. The gripper head  160  is preferably generally arcuate in shape to correspond with an outer surface of a container  20  and may include a tactile gripping surface  165 . The gripping surface  165  may be replaceable using a removable plate or similar arrangement as shown in  FIG. 5 . A quick change feature to facilitate tool-less removal and replacement may be incorporated into the can gripper  130  to permit changeover and/or replacement of the can gripper  130  and/or individual components thereof. 
     In addition, each can gripper  130  may include a pivot follower  170  extending from each can gripper  130 . The pivot follower  170  preferably comprises a pin that engages with a corresponding shaft in the central wheel  100  to permit each can gripper  130  to pivot and move in accordance with the radial position cam  110  and/or the angle position cam  120 , as best shown in  FIG. 3 . 
     In accordance with the arrangements described above, the plurality of can grippers  130  are thereby positioned radially around the central wheel  100  and positionable between a constant pitch and a variable pitch between each adjacent can gripper  130 . For instance, as shown in  FIG. 4 , the can grippers  130  are preferably positioned at a constant pitch between an infeed and an outfeed and a variable pitch between the outfeed and the infeed. As shown, the infeed is approximately 135 degrees from the outfeed. 
     In the context of the applicating machine  10  described herein for applying a flexible carrier  30  to a plurality of containers  20  provided from an infeed, the transfer device  60  preferably moves oriented containers from the orienter  50  to the jaw drum  70  from a first pitch to a second pitch wherein the first pitch is greater than the second pitch. This is possible, in part, because the transfer device  60  is preferably moveable in a rotational and a radial direction. 
     In accordance with the above description, a corresponding method for packaging a generally continuous string of container carrier  30  and containers  20  includes providing a generally continuous string of container carrier  30  and containers  20  to a transfer device  60  at a first pitch and a first centerline.  FIG. 6  shows a transfer between the orienter  50  and the starwheel  60  at the pickup location and  FIG. 7  shows a transfer between the starwheel  60  and the jaw drum  70  at the dropoff location. It is observed that the pitch between adjacent can grippers  130  is larger at the pickup location shown in  FIG. 6  than the pitch shown in  FIG. 7  at the dropoff location. Likewise, the centerline of the respective can grippers  130  at the pickup location is different from the centerline of the respective can grippers  130  at the dropoff location. 
     The containers are transferred in a fixed angular position through the transfer device  60  to a second pitch and a second centerline and subsequently applied with the container carrier to create unitized packages of containers. Specifically, in one preferred embodiment, a plurality of can grippers  130  are moved in an angular and radial direction as the can grippers rotate  130  around the transfer device  60 . 
     Accordingly, the starwheel  60  or transfer device may transfer each container  20  in a common or generally identical angular position to each adjacent container for placement in the carrier  30 . Alternatively, each container  20  may be fixed in a different angular position to each adjacent container  20  to create a cohesive “billboard” effect on the resulting package. 
     While in the foregoing specification this invention has been described in relation to certain preferred embodiments thereof, and many details have been set forth for purpose of illustration, it will be apparent to those skilled in the art that the system and method according to this invention are susceptible to additional embodiments and that certain of the details described herein can be varied considerably without departing from the basic principles of the invention.