Abstract:
The present invention relates to an apparatus for printing pattern or indicia onto a gelatin ribbon. It comprises a transfer station with a print roll and a motor-driven casting roll provided for forming a gelatin ribbon. The transfer station is positioned in relation to the casting roll in such a way that the gelatin ribbon is sandwiched between the casting roll and the transfer station; elastic tackiness of a passing gelatin ribbon causes the rotation of the print roll. The apparatus further comprises an adjustment means, wherein the adjustment means are adapted to provide finely-tuned positioning of the transfer station in relation to the casting drum, and balance pressure exerted by the transfer station on the passing gelatin ribbon thus facilitating on optimal printing result.

Description:
[0001]     This application is based on a Provisional application Ser. No. 60/564,692 filed on Apr. 26, 2004. 
     
    
       [0002]     The present invention relates to a method and apparatus for printing a pattern or indicia onto a gelatin ribbon, said ribbon being subsequently used in an encapsulation process. Encapsulation of products inside a gelatin shell has existed since the 1940s, the basics of which are described in U.S. Pat. No. 2,234,479.  
         [0003]     In brief, a standard encapsulation process comprises two soft gelatin ribbons fused together by a die into capsules containing a product. As the gelatin ribbons are fused by the die, a liquid product is injected through tubes into the eventual capsules. Products may be anything from marking paint for paintball applications to pharmaceuticals intended to be swallowed by consumers.  
       BACKGROUND OF THE INVENTION  
       [0004]     Considering the wide use of encapsulation by modern industry, there is a need to mark capsules with indicia or a pattern for identification or aesthetic purposes. Marking capsules in their final state is difficult and expensive, requiring extra labor and chemicals that may cause adverse effects to consumers. Thus, printing on the gelatin ribbon prior to the encapsulation process is more a cost-effective and accepted practice.  
         [0005]     There is known U.S. patent application Ser. No. 10/236669 for “Method and apparatus for printing a ribbon for packaging gelatin capsules” invented by Cruttenden, Holland, Tidy, and Rowe. This application uses a transfer station to mark the gelatin ribbon prior to encapsulation. The transfer station comprises a print roll (a flexographic printing plate wrapped around a cylinder) that picks up ink off an inking roller immersed in an ink tray. The transfer station is located along the gelatin ribbon&#39;s path between the casting drum and the oiling station. The print roll is in contact with the passing gelatin ribbon, driven by a motor at the same speed as the ribbon and depositing indicia or a pattern onto said ribbon. However, this application presents several disadvantages over the present invention. Firstly, it is over twenty times more expensive than the present invention: it requires sensitive and complex components such as a stepper motor, an encoder, prologic controls, speed controllers, air cylinders, and a gear drive assembly. Secondly, this application requires electricity and an air compressor to function. Considering the multitude and inter-dependence of components, this application is more prone to failure and down-time.  
       SUMMARY OF THE INVENTION  
       [0006]     It is therefore the object of the present invention to provide an improvement to the above application. The transfer station of the present invention also comprises a print roll and an inking roll (anilox roll) immersed in an ink tray. However, instead of printing on the gelatin ribbon in mid-air thus necessitating an electric motor and logic controls to coordinate proper turning of the printing assembly, the apparatus of the present invention functions using the friction of the passing gelatin ribbon, which is an important part of the present invention. The transfer station of the present invention is positioned so that the passing gelatin ribbon is sandwiched between the motor-driven gelatin casting drum and the transfer station&#39;s print roll. The turning force and pressure exerted by the casting drum combined with the elastic tackiness of the gelatin ribbon causes the print roll to turn at the same speed as gelatin ribbon. Rotation of the print roll cause rotation of the anilox roll adjacent to the print roll.  
         [0007]     Another important advantage of the present invention is the ease of routine preventive maintenance: the transfer station of the present invention can be removed, serviced and replaced much faster than U.S. patent application Ser. No. 10/236669, thus resulting in improved productivity and reduced labor hours. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]      FIG. 1  is a perspective view of the transfer station according to the embodiment of present invention.  
         [0009]      FIG. 2  is a side cross-sectional view of  FIG. 1 .  
         [0010]      FIG. 3  is a side view of  FIG. 1 .  
         [0011]      FIG. 4  is a side cross-sectional view of the transfer station of  FIG. 1  mounted on its base assembly.  
         [0012]      FIG. 5  is a perspective view of the present invention in use.  
         [0013]      FIG. 6  is a perspective view of the base assembly of  FIG. 4 .  
         [0014]      FIG. 7  is a side view of  FIG. 6 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0015]     The present invention relates to a method and apparatus for imprinting a pattern or indicia onto a gelatin ribbon in an encapsulation process. Instead of using an auxiliary driving means to turn the printing means, the present invention utilises pre-existing driving means in the form of the casting drum that shapes and feeds said gelatin ribbon. The invention relies on the combination of outwardly pressure and turning force exerted by said casting drum, pressure of the print roll and the elastic tackiness of said gelatin ribbon; said combination causes the present invention to function without resorting to auxiliary driving means, which is a substantial advantage of the present invention over all known prior art.  
         [0016]     Referring to drawings,  FIGS. 1-3  show the preferred embodiment of the printing apparatus according the present invention comprising a transfer station  10  placed into a housing  15  and having a print roll  20  and an inking or anilox roll  30 . Print roll  20  is made of extruded rubber similar to a rubber stamp with a logo or pattern and anilox roll  30  is made of laser-engraved ceramic-coated stainless steel. A doctor blade  40  is mounted adjacent to the anilox roll  30  and is provided to scrape excess ink off said anilox roll. An ink tray  35  contains ink for printing. The anilox roll  30  acts as an ink-metering system and is partially submerged in the ink tray  35 .  
         [0017]     Positioning of the transfer station  10  in relation to the casting drum  60  and regulating optimal pressure exerted by the print roll  20  on the gelatin ribbon  70  is provided by different adjustment means shown on  FIGS. 1-7 , described below.  
         [0018]      FIG. 1  shows third adjustment means that are located on the transfer station  10 , comprising two knobs  120  facilitating forward/backward movements of the anilox roll  30  towards the print roll  20  (movement shown by arrows C). Fourth adjustment means are located on the transfer station  10 , comprising two knobs  130  that facilitate movements of doctor blade  40  towards anilox roll  30  (shown by arrows D).  
         [0019]      FIG. 2  shows a cross-sectional view of transfer station  10 , showing anilox roll  30  in ink tray  35  and doctor blade  40  adjacent to anilox roll  30 .  
         [0020]      FIG. 4  is a side cross-sectional view of the preferred embodiment and  FIG. 5  is a perspective view of the preferred embodiment in operational mode. These Figures show transfer station  10  having print roll  20 , anilox roll  30  in ink tray  35  and doctor blade  40  adjacent to anilox roll  30 . Transfer station  10  is removably mounted on a base assembly  50  by means of a mounting bolt (not shown). First adjustment means are located on the base assembly  50  and comprise a mount bracket  80  having an elongated slot  56  provided for mounting screw  55  facilitating lateral left/right adjustments for setting base assembly  50  in exact alignment with the casting drum  60  (shown by arrows X). Second adjustment means are located on the base assembly  50  and comprise a crank  90  facilitating forward/backward adjustment of the transfer station  10  towards the casting drum  60  (shown by arrows A). Fifth adjustment means are located on the base assembly  50  and comprise a knob  100  facilitating vertical up/down adjustment of the transfer station  10  (shown by arrows Y). Sixth adjustment means are located on the transfer station  10  and comprise two knobs  110  facilitating pivotal adjustments of the transfer station  10  in a horizontal plane (shown by arrows B). All six adjustment means are operated manually.  
         [0021]     To achieve optimal printing results, print roll  20  of the transfer station of the present invention  10  must remain in a finely-tuned balance with moving gelatin ribbon  70 , wherein said print roll turns at the same speed as gelatin ribbon  70 . Gelatin ribbon  70 &#39;s elastic and tacky properties are ideally mated to print roll  20 &#39;s rubber coating. However, if print roll  20  is placed too close to gelatin ribbon  70 , it will cause said ribbon to stretch, deform or tear; if the print roll  20  is placed too far from ribbon  70 , it will lack the necessary friction to turn at the same speed as gelatin roll  70 , thus blurring or distorting the desired printed image. To maintain this balance, the preferred embodiment has six manual adjustment movements, which is an important feature of the present invention.  
         [0022]      FIGS. 6 and 7  depict the base assembly  50  of the present invention comprising the mounting bolt  55  provided to fasten the mounting bracket  80  by means of bracket slot  56  to the base assembly  50 . Base channel  116  is provided to house the crank  90  adapted to adjust the forward/backward movements of the transfer station  10 . Platform  114  is provided for mounting the transfer station  10  onto the base assembly  50 . Height adjustment channel  116  is provided to house the height adjustment knob  100  facilitating vertical up/down adjustments of the transfer station  10 .  
         [0023]     With reference to  FIG. 5 , the first step in aligning transfer station  10  with gelatin ribbon  70  begins with setting base assembly  50  in an exact alignment with casting drum  60  on the mount bracket  80  using mounting screw  55  inserted into the bracket slot  56 . Mount bracket  80  allows for lateral left/right adjustment movement, as identified by arrows X. Once base  50  is in exact alignment with drum  60 , transfer station  10  is moved toward drum  60  using crank  90 , wherein the crank  90  controls forward/backward adjustment movement as identified by arrows A.  
         [0024]     Transfer station  10  is moved toward drum  60  until print roll  20  comes in contact with moving gelatin ribbon  70  and begins to turn due to ribbon  70 &#39;s motion. Anilox roll  30  is moved toward print roll  20  using knobs  120  so that anilox roll  30  makes contact with print roll  20 ; knobs  120  control anilox roll  30  forward/backward adjustment movement identified by arrows C. Print roll  20 &#39;s turning motion is transferred to anilox roll  30 , and anilox roll  30  starts picking up ink out of ink well  35 . Doctor blade  40  is adjusted using knobs  130  so that it exerts an even pressure along the length of anilox roll  30 , wherein knobs  130  control doctor blade  40  pressure adjustment movement as shown by arrows D on  FIG. 2 . As anilox roll  30  turns and picks up ink out of ink well  35 , doctor blade  40  subsequently scrapes off excess ink leaving only the appropriate amount of ink on anilox roll  30 . Ink is transferred from the anilox roll  30  through contact to print roll  20 , which in turn transfers said ink to gelatin ribbon  70 .  
         [0025]     Balance between transfer station  10  and gelatin ribbon  70  can also be finely-tuned using knob  100 , being vertical up/down base adjustment movement shown by arrows Y on  FIG. 4 , as well as knobs  110  facilitating horizontal pivotal adjustment movement shown by arrows B on  FIG. 5 . The amount of ink that is allowed to transfer to print roll  20  can be controlled through the third or anilox roll adjustment movement provided by knobs  120  (arrows C) and fourth or doctor blade  40  pressure adjustment movement provided by knobs  130  (arrows D). It must be emphasized that the present invention is not restricted to the sequence of adjustment steps shown above and any other possible sequence of steps may be used for the same purpose with the same final result.  
         [0026]     The present invention has the following advantages over prior art, in particular U.S. application Ser. No. 10/236669: 
        it does not use any utilities;     all adjustments are made manually, which is very important feature of the present invention;     the printing apparatus of the present invention is not gear driven, electrically powered or pneumatically driven;     there is no need for stepping motors, speed controllers or any other similar means, thus eliminating potential malfunctions and need for routine maintenance.        
 
         [0031]     It must be emphasized that present invention is not restricted to the use of printing apparatus shown on  FIGS. 1-3 ; any similar equivalents could be used for the same purpose. Adjustment means also are not restricted to the embodiments shown above and any other equivalent arrangements could be used for the same purpose within the scope of the present invention.  
         [0032]     Thus, it can be seen that the objects of the present invention have been satisfied by the structure presented hereinabove. While in accordance with the Patent Statutes, only the best mode and preferred embodiments of the present invention have been presented and described in detail, it is to be understood that the invention is not limited thereto or thereby. Accordingly, for an appreciation of the true scope and breadth of the invention, references should be made to the following claims.