Patent Publication Number: US-6907822-B2

Title: Dry offset rotary printer for labeling wine corks

Description:
TECHNICAL FIELD AND BACKGROUND OF THE INVENTION 
   This invention relates to automated printing machines; and more particularly, to dry offset printing machines. As the demand for wine has increased, so has the demand for natural cork stoppers. To reduce demand for natural cork stoppers, containers other than bottles requiring cork stoppers, such as collapsible bags in boxes and bottles with screw cap lids, have been used. However, the buying public typically perceives collapsible bags stored in boxes with exposed spigots and screw cap bottles as indicators of inferior quality wine. To meet the demand for cork stoppers, synthetic cork stoppers have been developed. These synthetic cork stoppers are made from polymeric materials that have been extruded, or molded during a molding process. These synthetic corks have characteristics similar to their natural counterparts. 
   In the wine industry, corks are frequently printed with words and other indicia identifying the vineyard where the wine was produced or where the wine is bottled. Printing of natural cork stoppers is typically done using a rotary letter press or rotary letter flex printing system which utilizes a reverse reading hard or soft printing plate which has ink placed on the raised surface. The raised surface of the plate then makes contact with the natural cork, thus transferring the appropriate image. This printing process is typically limited to single color printing. 
   Printing machines used for printing indicia on natural cork stoppers have been found to be ineffective when used with synthetic cork stoppers. The synthetic stoppers are not as absorbent as natural cork and the printing on such corks, regardless of transfer method, require a forced drying of the printed ink. Additionally, the synthetic corks have a lower coefficient of friction at their surface and require a surface treatment, which oxidizes the surface allowing the printing ink to “flow out” when applied to the surface. 
   Therefore it would be advantageous to have a printing machine capable of imprinting synthetic cork stoppers with forced surface pretreatment and forced ink drying. It would also be advantageous to have a printing machine capable of printing synthetic cork stoppers that more securely holds the synthetic stoppers to reduce the likelihood of machine jams. It would also be advantageous to have a printing machine capable of printing synthetic cork stoppers which is more compact than previously known synthetic cork printing machines. 
   SUMMARY OF THE INVENTION 
   Therefore, it is an object of the invention to provide a printing machine capable of imprinting synthetic cork stoppers with little smearing. 
   It is another object of the invention to provide a printing machine capable of printing synthetic cork stoppers that more securely holds the synthetic stoppers to reduce the likelihood of machine jams. 
   It is another object of the invention to provide a printing machine capable of printing synthetic cork stoppers which is more compact than previously known synthetic cork printing machines. 
   It is another object of the invention to provide a printing machine which completely processes a synthetic cork in a single, continuous process. 
   It is another object of the invention to provide a printing machine which imprints synthetic corks which includes both forced surface treatment before printing and forced drying of the cork after printing. 
   These and other objects of the present invention are achieved in the preferred embodiments disclosed below by providing a rotary printing machine for the printing of synthetic cork stoppers of the type having a surface which is normally non-ink receptive. A Ferris wheel mechanism is provided, having a plurality of evenly spaced carriers mounted a predetermined radial distance from and parallel to the axis of rotation for the Ferris wheel mechanism, each carrier for rotatably holding a synthetic cork stopper. An indexing drive system controls incremental rotation of the Ferris wheel mechanism through a predetermined sequence of steps, and a cork feeder introduces a single synthetic cork stopper into each of the carriers as empty ones of the carriers are presented one-by-one at the cork feeder. A corona discharger treats the surface of each synthetic cork stopper prior to being printed with sufficient energy to alter the surface energy of the cork sufficiently to permit receptivity of printing ink. A rotary printing system rotatably imprints with ink the surface of each held synthetic cork stopper with an image. 
   According to one preferred embodiment of the invention, a carrier driver is provided for rotating each cork stopper as the surface of the stopper is being treated by the corona discharger. 
   According to another preferred embodiment of the invention, the Ferris wheel mechanism further comprises a coaxially-mounted drive axle coupled to the indexing drive system, and two parallel, spaced apart circular plates coaxially mounted on the drive axle. 
   According to yet another preferred embodiment of the invention, each carrier further comprises a stationary holder rotatably mounted on one of the plates, a movable holder rotatably mounted on the other of the plates opposite the stationary holder, the moveable holder being moveable between an open position and an engaged position with respect to the stationary holder such that when in the open position the synthetic cork stopper drops out of the carrier and the Ferris wheel mechanism and when in the engaged position the synthetic cork stopper is held between the moveable and stationary holders; and movement means for moving the moveable holder between the open and engaged positions. 
   Preferably, the stationary holder and moveable holder have concave surfaces for receiving the ends of the synthetic cork stopper. 
   According to yet another preferred embodiment of the invention, the stationary holder and moveable holder are removably mounted on their respective plates. 
   According to yet another preferred embodiment of the invention, the stationary holder and moveable holder each further comprise a removably mounted cup for holding the synthetic cork. 
   According to yet another preferred embodiment of the invention, a slip clutch is provided for interconnecting the drive axle to the indexing drive system means. 
   According to yet another preferred embodiment of the invention, the printing machine includes a plurality of carrier spin drivers positioned adjacent the Ferris wheel mechanism at each step where the synthetic cork stopper is being treated, printed and dried, each carrier spin driver having a continuously rotating drive wheel, and a spin pulley coaxially mounted on one of the rotatable holders in each carrier, the spin pulley removably engageable with the drive wheel of a carrier spin driver when the carrier is positioned at a step where the synthetic cork is being treated, printed and dried. 
   According to yet another preferred embodiment of the invention, the dry offset rotary printing means further comprises a plurality of rotary print heads with each print head providing a different color in an imprinted image. 
   According to yet another preferred embodiment of the invention, the Ferris wheel mechanism further comprises a coaxial, rotatably mounted drive axle coupled to the indexing drive system means and a circular plate coaxially mounted on the drive axle. 
   According to yet another preferred embodiment of the invention, each carrier further comprises a stationary holder rotatably mounted on the surface of the plate and a mounting arm mounted on the surface of the plate adjacent each stationary holder. A movable holder is rotatably mounted on the mounting arm opposite the stationary holder, and is moveable between an open position and an engaged position with respect to the stationary holder such that when in the open position the synthetic cork stopper drops out of the carrier and the Ferris wheel mechanism and when in the engaged position the synthetic cork stopper is rotatably held between the moveable and stationary holders. Movement means permit movement of the moveable holder between the open and engaged positions. 
   According to yet another preferred embodiment of the invention, the printing machine further comprises a plurality of carrier spin drivers positioned adjacent the Ferris wheel mechanism at each step where the synthetic cork stopper is being treated, printed and dried, each carrier spin driver having a continuously rotating drive wheel, and a spin pulley coaxially mounted on one of the rotatable holders in each carrier, the spin pulley removably engageable with the drive wheel of a carrier spin driver when the carrier is positioned at a step where the synthetic cork is being treated, printed and dried. 
   An embodiment of the method for printing indicia on synthetic cork stoppers according to the invention comprises the steps of introducing a single synthetic cork stopper of the type having a normally non-ink receptive surface into a carrier of a Ferris wheel mechanism, treating the synthetic cork stopper surface prior to being printed to render the surface at least temporarily receptive to printing ink, rotatably imprinting an image on the surface of the synthetic cork stopper in the carrier of the Ferris wheel mechanism, drying the ink on freshly imprinted synthetic cork stopper, indexing the rotation of the Ferris wheel mechanism to present the carrier of the Ferris wheel mechanism to stations for treating, imprinting, and drying corks held in the carriers of the Ferris wheel mechanism. 
   According to one preferred embodiment of the invention, the method includes the step of moving a moveable holder of the carrier with respect to a stationary holder of the carrier between an open position and an engaged position such that the synthetic cork stopper drops out of the carrier in the open position and the synthetic cork stopper is held between the moveable and stationary holders in the engaged position. 
   According to another preferred embodiment of the invention, the method disengaging a drive axle from an indexing drive system in response to a jam so that the indexing rotation ceases. 
   In alternative embodiments, the carriers are removably mounted in the Ferris wheel mechanism, the carriers have removable cups used for holding the synthetic corks, and the carriers may be independently rotated at various carrier positions using a carrier spin drive. In other embodiments, the Ferris wheel mechanism comprises a single circular plate mounted on the drive axle with the cork stopper carriers mounted on one side of this plate. Further, a slip clutch mechanism may be provided between the Ferris wheel mechanism and the indexing drive system to reduce the likelihood of damage to the indexing drive should jams occur. 
   Because each cork is individually held in place during the steps of corona treatment, printing and drying, the down time caused by corks not properly releasing from the print drums is reduced. Further, the Ferris wheel mechanism allows a misfed cork to drop through the mechanism and out of the machine. Lastly, because the carriers and/or their cups are readily removable, the printing machine of the present invention may be quickly retooled for use with a variety of lengths and diameters of synthetic corks. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Some of the objects of the invention have been set forth above. Other objects and advantages of the invention will appear as the invention proceeds when taken in conjunction with the following drawings, in which: 
       FIG. 1  is a schematic representation of a dry offset rotary printing machine according to one embodiment of the present invention; 
       FIG. 2  is an elevational illustration showing the Ferris wheel mechanism, the printing of cork stoppers, as well as, schematically showing the indexing drive and the use of a carrier spin drive to independently rotate the carriers; 
       FIG. 3  is a detailed isometric view of the synthetic cork feed mechanism; 
       FIG. 4   a  is a partial sectional view illustrating the assembly of the synthetic cork carriers in both the open position; 
       FIG. 4   b  is a sectional view illustrating the assembly of the synthetic cork carriers in the engaged position; 
       FIG. 5  is a partial sectional view of the machine illustrated in the above Figures showing the cam and cam follower used to move the movable carrier between the open and engaged positions; 
       FIG. 6  is a side elevational view of the silicone application station of the printing machine; 
       FIG. 7  is a flow diagram of a preferred embodiment of the process according to a preferred embodiment invention. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT AND BEST MODE 
   Referring now specifically to the drawings, a cork printer according to the present invention is illustrated in FIG.  1  and shown generally at reference numeral  100 . 
   As used herein, the terms “cork,” “corks,” and “cork stopper” refer to synthetic and natural cork stoppers. Elements having the same or similar functions in the various Figures have similar reference numerals. 
     FIG. 1  illustrates a dry offset rotary printing machine  100  used for the printing of synthetic cork stoppers. The printing machine  100  comprises a rotatable Ferris wheel mechanism  102  having a plurality of evenly spaced carriers mounted a pre-determined radial distance from and parallel to the axis of rotation of Ferris wheel mechanism  102 . Each carrier rotatably holds a synthetic cork stopper to be treated, printed and dried in the machine. Ferris wheel mechanism  102  illustrated in  FIG. 1  has sixteen carrier positions, numbered 1 through 16. Each of these positions has a cork stopper carrier although it is not required. A larger or smaller number of carriers may be provided based on design choice. The vertical orientation of the Ferris wheel advantageously decreases the amount of floor space needed for the footprint of machine  100 . 
   Shown mounted adjacent to carrier position  1  is feed mechanism  104 . This mechanism introduces a single cork into each of the carriers as the carriers rotate past feed mechanism  104 . A cork supply bin  106  attaches to cork feed mechanism  104  via a feed tube  108 . Cork feed mechanism  104  is further explained with reference to FIG.  3 . 
   Shown at positions  3  and  4  is a dual corona discharge treating unit  112  having corona discharge heads  114  positioned adjacent carrier positions  3  and  4  so that the corona discharge impinges upon the surface of the cork stoppers held in the carriers at those positions. Preferably, corona unit  112  is a Dual Spot Generator, Model No. 7107D02 manufactured by Tantec, Inc. of Schaumburg, Ill. Corona treating of the synthetic corks allows the cork surface to better accept the inks used in a dry rotary offset printing. 
   Mounted adjacent carrier position  6  is an offset rotary transfer print drum  120 . Shown positioned adjacent to the rotary drum  120  are two dry offset rotary print heads  122 . Each print head includes a continuously driven ink fountain roller with a roller inking arrangement. Print heads  122  transfer an inked image onto one or more raised surfaces or platens  121  of print drum  120  which then transfers the ink image onto the surface of the cork stopper located at carrier position  6 . Print drum  120  is positioned so that platens  121  contact both the surface of a cork stopper at position  6  and the image plate in print heads  122  in their rotation. The width of raised platen  121  are typically slightly less than the length of the longest cork stopper to be printed. The length of raised patent  121  is about equal to or longer than the circumference of the largest diameter cork stopper to be printed. The print heads preferably used in the present invention are Model Half Size 6-3000 Series print heads manufactured by Apex Machine Company of Ft. Lauderdale, Fla. Other types of dry offset printing systems may be used with the Ferris wheel mechanism. 
   Mounted adjacent to carrier position  7  through  11  is ultraviolet (UV) drying or curing assembly  130  that dries freshly imprinted corks at those positions. The drying assembly  130  comprises an UV light along with fan and drying elements  132  extending therefrom and about Ferris wheel mechanism  102 . Preferably, the UV drying assembly  130  is a Model UVPAK manufactured by Fusion AETEK UV Systems, Inc. of Romeoville, Ill. Other types of drying or curing assemblies may be used. 
   Shown adjacent to carrier positions  13  through  15  is bin  140  that collects the dried imprinted corks exiting the machine, typically at carrier position  14  or  15 . Attached to drive axle  103  of Ferris wheel mechanism  102  via belt  154  is an indexing drive system  150 , such as a servo motor or mechanical cam indexer. The indexing drive system controls the rotation of the Ferris wheel mechanism through a predetermined sequence of steps at which the various operations are performed. These steps are the feeding of a synthetic cork into carriers at carrier position  1  and then rotating the Ferris wheel mechanism and held corks through the carrier positions at which the held cork stoppers are corona treated, printed, dried and removed. In operation, indexing drive system  150  moves Ferris wheel mechanism  102  through a predetermined amount of rotation. For the 16 station unit shown, this would mean approximately 22.5° of rotation per step. The length of time at which Ferris wheel mechanism  102  is stopped at each station is determined primarily by the length of time needed to imprint the cork which occurs for the machine shown at carrier position  6 . An indexing drive system for use in the present invention is Model P-325 indexer manufactured by Ferguson Company of St. Louis, Mo. A slip clutch mechanism as is known in the art (not shown) may be interconnected between indexing drive system  150  and drive axle  103  to reduce the likelihood of damage to the indexing drive and printing machine in the event that there is a jam in the printing machine. One such slip clutch mechanism is Model Size 1 manufactured by Mayr Corporation of Waldwick, N.J. or Torque Limiter Model 250A manufactured by Morse Industrial Corporation of Ithaca, N.Y. 
   Ferris wheel mechanism  202  is shown in FIG.  2  and is comprised of a horizontally oriented, rotatably mounted drive axle  203  that is coupled to indexing drive system  250 . Drive axle  203  is mounted in or on bearings  251  as is known in the art. Curved arrow  252  indicates the direction of rotation of Ferris wheel mechanism  202 . Two parallel, spaced apart, preferably circular plates  260 ,  261  are coaxially mounted on drive axle  203  and support the cork stopper carriers positioned intermediate plates  260 ,  261 . Plates  260 ,  261  may be solid or have a hub, spokes and rim arrangement. The number of carriers desired and the room needed to mount the various pieces of treating, printing and drying equipment about the outer circumference of Ferris wheel mechanism  202  determines the diameter of the plates. Alternatively, a single plate may be used to form the Ferris wheel mechanism. In this alternate embodiment, the carriers are positioned in a cantilevered fashion from one face of the plate. For example the stationary holder may be mounted on the surface of the plate while the opposite moveable contact is mounted on a C- or L-shaped arm extending outwardly from the plate&#39;s surface. 
   Each carrier  270  comprises a pair of opposed rotatable holders, one of which is stationary, the other moveable. Preferably, all of the stationary holders  272  mount on plate  260  with the corresponding moveable holders  274  mounting on plate  261 . Other arrangements are possible and the exact arrangement is not critical. Both holders are rotatable in their mounted positions, and, preferably, both holders are removably mounted. Preferably, movable holders  274  are linearly movable between an open position  275  and an engaged position  276  with respect to their corresponding stationary holder  272  when cork stopper  278  is clamped in position. Moveable holder  274  may be moved between these two positions by springs, linkages, linear actuators or the like as is well known. At open position  275 , a printed cork  276 A drops out of carrier  270  and Ferris wheel mechanism  202  into container  240 . Also new or unprinted cork  277  may be inserted into carrier  270 . In the engaged position, held corks  278  are clamped between movable holder  274  and stationary holder  272  of each carrier  270 . Unprinted cork  277  is shown on feed mechanism  204  waiting to be clamped into position. Cork feed tube  208  is shown filled with additional unprinted corks  277  queued up for entry into Ferris wheel mechanism  202 . As shown there the cork stoppers are aligned along their longitudinal axis—the preferred orientation for the printing operation. 
   Print drum  220  is shown having an reverse ink image  221  which is brought into contact with surface  279  of cork  278  at carrier position  6  and rotatably prints the surface of this held cork. Also shown is carrier spin drive  290  that is used to rotate the carriers and any cork stopper held therein. Advantageously, this direct rotation of the cork stopper ensures that the cork stopper is effectively treated, printed and dried. Preferably at each carrier position at which a treating, drying or printing operation occurs, a carrier spin drive unit is provided. Spin drive unit  290  has a continuously spinning drive wheel  292  that engages a carrier to spin or rotate the carrier. Drive wheel  292  is shown engaging stationary holder  272  that is adjacent print drum  220 . Moveable holder  274  may also be used to engage drive wheel  292 . 
   Drive wheel  292  may engage more than one carrier at a time, depending, of course, on the diameter of the drive wheel used. Drive wheel  292  engages a carrier  270  as Ferris wheel mechanism  202  indexes into position. When Ferris wheel mechanism  203  indexes and rotates to the next position, the spinning carrier disengages from drive wheel  292  due to the rotational motion of Ferris wheel mechanism  203 . Drive wheel  292  is sized so the drive wheel rotational path and carrier path are tangent or coincident only about a given carrier position or only about positions adjacent to that given position. 
   The use of the carrier spin drive allows the cork to be rotated when being treated, printed or dried. This ensures that the entire surface of the cork is properly treated at each of the respective stops in the machine. By providing a positive drive to the held cork rather than letting the held cork be rotated by the print drum, a better transfer of the inked image occurs. Drive wheel  292  comprises a pulley having a rubber O-ring or similar material in the groove of the pulley (see  FIG. 4   b ). Spinning the carriers may be accomplished by means other than the drive wheel and spin pulleys. For instance, gears, belts or linkages may be used to achieve the same effect. A planetary gearing system may also be employed as is known in the art. Further, carrier rotation may be provided at every carrier position between carrier position  1  where new corks enter the Ferris wheel and the exit carrier positions. 
   To load the carriers, a single cork is presented to each carrier as it is rotated into carrier position  1 .  FIG. 3  depicts feed mechanism  304  that performs this function. The exit end  309  of feed tube  308  is mounted to a receiving platform  310 . In supply tube  308  and shown in dashed line are new synthetic cork stoppers  377 . Stoppers  377  are queued and aligned in a single file ready to exit feed tube  308  and are biased to do so if a free space is available on receiving platform  310 . Biasing preferably is done using a gravity feed system for the cork stoppers. Cork stopper  377  upon exiting feed tube  308  comes to rest against stop  311 . Linear actuator  315  is positioned intermediate end  309  of supply tube  308  and stop  311 . End  316  of linear actuator  315  adjacent the stopper is C- or U-shaped in cross section. This holds new cork stopper  377  in alignment as linear actuator  315  feeds the stopper into the Ferris wheel mechanism. 
   The double headed arrow indicates the reciprocal linear motion of linear actuator  315  into and away from the carriers. Positioned adjacent to and in line with end  316  of linear actuator  315  and attached to receiving platform  310  is holding cradle  317  on which positioned new cork  377  is shown. Holding cradle  317  is curved to approximately the same radius as that of the cork stopper to be printed. Should larger or smaller cork diameter stoppers need to be printed, the curvature may be adjusted or a new cradle having the appropriate curvature may be installed. When a carrier is present at carrier position  1 , holding cradle  317  is positioned intermediate the stationary and moveable holders. A carrier engages or clamps cork  377  that is in holding cradle  317  and when the Ferris wheel mechanism is rotated to the next position, holding cradle  317  is emptied of its new cork stopper  377 . As the next carrier is being rotated into carrier position  1 , linear actuator  315  actuates and pushes new cork  377  adjacent stop  311  onto holding cradle  317 . During the process of loading holding cradle  317  with the next new cork stopper  377 , actuator  315  blocks exit end  309  of feed tube  308  preventing another new cork stopper  377  from exiting feed tube  308  until linear actuator  315  retracts to its rest position. Feed mechanism  304  reliably introduces a single synthetic cork stopper into each carrier when it reaches carrier position  1 . 
   Referring now to  FIGS. 4   a  and  4   b , cork stopper carrier  470  is shown in the open and engaged positions, respectively. Stationary holder  472  mounts in an opening  441  provided in plate  460 . Provided in opening  441  is hollow cylindrical housing  442  having at each end thereof circular bearings  443 . Cylindrical rod  444  is inserted through bearings  416  and extends substantially perpendicularly and outwardly for each face of plate  460 . End  445  of rod  444  between plates  460 ,  461  has removably mounted thereon cup  446  for engaging with or receiving an end of cork  477 . Cup  446  can be attached by various means as is known in the art, including the use of threaded connections, keyed connections, or a bolt and nut connection. Cup  446  has a flat surface or face for holding a cork stopper or is a shaped face  447 , such as a concave or convex face, corresponding to the shape of the ends of the cork stoppers to be printed. At opposite end  448  of rod  444  is removably mounted a spin pulley  449 . The rod  444 , spin pulley  449  and cup  446  rotate about axis  450  together as a unit in bearings  443 . 
   Movable holder  474  is similarly constructed and is removably mounted on the other plate  461  of the Ferris wheel mechanism. Because movable holder  474  is linearly movable there are some differences in its construction. Cylindrical rod  462  in movable holder  474  is longer than rod  444  of stationary holder  472  and is mounted in linear bearing  463  allowing rod  462  and cup  464  to be linearly moveable between the open and engaged positions. An O-ring seal  493  is provided where rod  462  exits housing  442 . Another seal  494  is provided at the other end of housing  442  where rod  462  is removably and rotatably connected to cup  464 . These seals protect the linear bearing from contaminants such as dirt and debris. Because of the use of a cam follower and guide bar arrangement that is described with reference to  FIGS. 4   a ,  4   b , and  5 , cup  464  is rotatably mounted on end  459  of rod  462  and rotates about axis  450 . The face of cup  464  that engages the end of a cork stopped is shaped as previously described for cup  446 . The added length in rod  462  allows movable holder  474  to receive or contact an end of cork  477  when placed in the engaged position. The end of cup  464  has an opening that receives end  459  of rod  462 . The opening may be fitted with a circular bearing. Because cups  446 ,  464  are removable, cups having different profiles may be used to accept cork stoppers having ends with configurations different from typical corks, such as champagne cork stoppers. 
   As previously described, when in the proper position to do so, spin pulley  449  engages with drive wheel  492  rotating carrier  470  and held cork stopper  478  about the centerline of carrier  470 . Preferably, each carrier  470  and/or cups  446  and  464  mounts, as is known in the art, to be readily removed to allow for retooling with different sizes carriers or cups should a substantially large or smaller diameter synthetic cork stopper need to be printed. The cups have approximately the same diameter as the cork stoppers that are to be printed. 
   Various subsystems may be used to transfer moveable holder  474  between the open and engaged positions. One such subsystem is described with reference to  FIG. 4   a . Attached adjacent to exterior end  465  of rod  462  ( FIG. 4   a ) is cam follower  466  which depends in a direction perpendicular to the centerline of rod  462 . Guide rod  467  mounts to plate  461  adjacent and parallel to rod  462 . Sleeve  468  slideably mounts on guide rod  467  and contains therein a linear bearing (not shown) which rides on guide rod  467 . Cam follower  466  attaches to sleeve  468 . The free end of guide rod  469  inserts in clamp collar  469  which is adjustably fixed in position on guide rod  467 . Mounted and compressed between sleeve  468  and collar  469  is spring  482  which biases holder  474  toward the engaged position and provides clamping force for holding the cork stopper. Stationary cam  480  is circular in shape and cut into its outer edge or rim is a step that forms an circular track  481  having an L-shaped cross section that extends outwardly from Ferris wheel mechanism. Cam follower  466  traverses track  481  as the Ferris wheel mechanism rotates through the various carrier positions. Guide rod  467  keeps cam follower  466  radially aligned with the axis of rotation of the Ferris wheel mechanism and in track  481  as cam follower  466  traverses track  481 . 
   Linear actuator  483 , such as an hydraulic or pneumatic cylinder, mounts on bracket  486  that, in turn, fastens to the exterior face of stationary cam  480  mounted on the drive axle and positioned adjacent plate  461 . The portion of cam  480  and segment of track  481  adjacent carrier position  1  is notched out. Inserted into the notch is cam block  485  that is sized to be closely received in the notch and which is also attached to drive rod  484  of linear actuator  483 . Cam block  485  also has an L-shaped track corresponding to track  481  cut into its outer edge such that when drive rod  484  extends the track in cam block  485  it aligns with track  481  in cam  480 . For a  16  carrier Ferris wheel mechanism the length of the track segment on the cam block spans an arc of approximately less than 20 degrees. 
   When a cam follower traverses onto the track segment in cam block  485 , linear actuator  483  actuates. On actuation, drive rod  484  retracts which linearly moves cam block  485  outwardly from the exterior face of cam  480 . Cam follower  466  also moves in the same direction linearly moving sleeve  468 , rod  462 , and cup  464 . This action transfers movable holder  474  to the open position and further compresses spring  482  (See  FIG. 4   a ). When linear actuator  483  deactivates, cam block  485  returns to its position aligned with cam  480  moving moveable holder  474  into the engaged position and clamping a cork resting in the feed cradle. The Ferris wheel mechanism indexes and the process repeats for the next cork stopper. A second linear actuator, second notch and second cam block may be provided at the exit station to remove the dried printed corks from each carrier by transferring the moveable holder from the engaged position to the open position as just described. If the cork exit position and the cork feed position are adjacent, a single actuator and a cam block having a longer track segment may be used as means to move the movable holder between the open and closed positions. Other arrangements as are known in the art may be used to transfer movable holder  474  between the open and engaged positions at both the cork feed position and the cork exit position. 
   In  FIG. 4   b , movable holder  474  is shown in the engaged position with held cork  478  clamped between the holders. Cam follower  466  is shown traversing track  481 . The moveable holder  474  remains in this position until held cork reaches the exit position. When the printed and dried cork reaches the exit position, typically carrier position  14  or  15 , movable holder  474  retracts to allow the printed and dried cork to exit the Ferris wheel mechanism and the machine. 
   Referring to  FIG. 5 , the mounting arrangement of cam  580  and cam follower  565  is seen. Cam  580  is fixed in position relative to rotating Ferris wheel mechanism  502 . Cam  580  is shown mounted adjacent plate  561  on bearing assembly  551 A that is mounted on drive axle  503 . Bearing assembly  551  allows Ferris wheel mechanism  502  to rotate about axis  590  but allows cam  580  to remain stationary. Cam follower  566  follows track  581  as Ferris wheel mechanism  502  rotates. In lieu of the linear actuator and cam block used at the exit position, the width of the track can be configured to narrow in the vicinity of the exit position thereby linearly shifting moveable holder  574  into the open position. 
   Referring now to  FIG. 6 , the silicone application station  600  applies a thin film of food grade silicone to the surface of the cork after printing. It is important that the silicone be applied evenly to the cork, as it serves to lubricate the cork during subsequent insertion into the bottle. It is also important that no silicone be inadvertently applied to the chucking elements. Silicone on the chucking elements may be transferred back to the printing blanket, causing contamination of the printing process. Silicone from a reservoir  605  flows through shut off valve  607  to a metering pump  610 . 
   The metering pump  610  is a commercially available model A7771-155HV from LMI. The metering pump  610  is controlled by the PLC of the printer  100 . The user can preset the amount of silicone to be applied. The amount of silicone pumped during each pump cycle is controlled at the pump  610 . Pump cycle frequency is controlled by the PLC. A precise quantity of silicone is therefore supplied by pump  610  via a hose  620  to the application station  625 . A line of holes placed in manifold  630  allows the silicone to form droplets on the upper surface of the manifold  630 . The droplets contact the surface of the cork as it is indexed from the ink drying station  130  where the corks are dried by curing the UV ink just applied. The cork with the silicone applied to its surface is then indexed into contact with a medical grade sponge  635 . The cork is driven via an external drive (not shown) causing it to rotate in contact with the sponge  635 . The sponge  635  transforms the droplets of silicone into a uniform film coating the entire surface of the cork except the ends held by the chucking device (not shown). The position of the holes in the manifold  630  and the width of the sponge  635  limit the area of silicone application to the cork, thus preventing silicone from be transferred to the chucking devices. 
   One advantage to this system is that the silicone is applied to the cork during the printing process. Other methods require additional handling. In typical prior art processes, the printed corks are placed in a large tumbler, silicone is added to the tumbler and the mixture of corks and silicone tumbled for a suitable amount of time. By directly applying the silicone within the printing system the additional handling and time required are eliminated. Another prior art method of applying the silicone requires the silicone be sprayed onto the surface of the cork. This method involves an expensive spray system because of the very small quantity of silicone being applied. Spraying also requires some method of transferring the cork from the printing device to the spraying device without the possibility of silicone migrating back to the printing system. The silicone application station  600  described here eliminates these problems. 
   The operation of the rotary printing machine  100  according to a preferred embodiment of the invention, and the related process, is illustrated and summarized in FIG.  7 . 
   Use of a dry offset rotary printer permits multiple colors to be employed in the images that are imprinted, unlike natural cork printing machines using the Gravure process. Further, the means to move the movable holder between the open and engage positions and from engaged to the opened position are not critical. Linear actuators or cams and cam followers as described may be used or other means as is known in the art may be used to move the movable holder. Although the movable holder is described as being linearly moveable between positions, it is also understood to those in the art that the moveable holder may move in a nonlinear fashion such as swinging through an arc. 
   A printing machine for printing synthetic corks is described above. Various details of the invention may be changed without departing from its scope. Furthermore, the foregoing description of the preferred embodiment of the invention and the best mode for the invention are provided for the purpose of illustration only and not for the purpose of limitation—the invention being defined by the claims.