Abstract:
A carrier for transporting pellet-like objects is disclosed. The carrier has a fixed jaw portion and a movable jaw portion positioned in spaced relation and opposite to the fixed jaw portion. The movable jaw portion is movable between an open and a closed position. When in the closed position, the jaw portions cooperate to grip the pellet-like item. The jaw portions are mounted on a movable conveyor which moves the carriers through a processing station which performs an operation on the pellet-like object while it is gripped by the jaw portions. An actuator extends from the movable jaw portion and is used to actuate the jaw portions into the closed position. A camming surface engages the actuator to close the jaw portions. Parts of the camming surface are sloped so as to gradually close and gradually allow the jaw portions to open.

Description:
FIELD OF THE INVENTION  
         [0001]    The invention relates to a carrier having movable jaws for holding pellet-like objects for transport in a machine which processes the pellet-like objects.  
         BACKGROUND OF THE INVENTION  
         [0002]    In the manufacture of products such as pharmaceuticals and confectionary items comprising pellet-like objects such as pills, capsules, lozenges, tablets and caplets, it is often desired to perform a manufacturing related operation on each object. Such operations may be as simple as inspecting or orienting the objects or as complex as printing or etching trademark or brand name indicia on each object. Mechanical operations, such as drilling holes in the objects, may also be performed as part of the manufacturing process.  
           [0003]    For operations such as printing indicia or drilling holes, the accuracy and precision of the operation is strongly affected by how the pellet-like objects are presented to the apparatus effecting the operation. Machines which perform such operations typically have an endless conveyor which passes through a hopper filled with bulk pellet-like objects. The conveyor has carrier bars with pockets shaped to conform to the shape of the objects. Each pocket in the carrier bar receives a pellet-like object as it passes through the hopper. The conveyor moves the carrier bars to a processing station, which may, for example, be a rotogravure printing wheel, a laser printer or a laser drill. As each bar passes the processing station, the desired operation, for example, printing or drilling, is performed on each pellet-like object held on each carrier bar. Upon completion of the operation, the conveyor moves the pellet-like objects onward for further processing.  
           [0004]    If the carrier bars do not present the pellet-like objects to the processing station in a consistent position and orientation, then the operation, printing or drilling, for example, will yield inconsistent results among the objects. Printing may be on different portions of each object, the holes may be drilled in different locations on each object and so forth. Such inconsistency is unacceptable for mass produced consumer items. Furthermore, it is often the case that the operation itself will affect the position and orientation of the pellet-like object on the carrier bar. Thus, even if the carrier bars present each object to the apparatus consistently in the same position and orientation, the actions of the apparatus may cause the object to be displaced or reoriented during the operation, adversely affecting the results of the operation. For example, a gravure wheel may move the object upon contact, causing the printing of the indicia to become distorted. Similarly, if an object shifts in position upon being hit by the beam from a laser drill then the hole drilled in the object will not be round but ellipsoidal in shape.  
           [0005]    The characteristics which make pockets in carrier bars easy to fill with pellet-like objects also make them relatively poor at consistently positioning and orienting the objects. For easy filling, the pocket may be oversized, for example, allowing the object to be located anywhere among a range of positions within the pocket. Oversized pockets moreover cannot effectively prevent the pellet-like object from shifting in position within the pocket during processing. There is clearly a need for a carrier mountable on a conveyor which positions and orients pellet-like objects consistently and holds the objects firmly during manufacturing operations so that operations such as printing or drilling may be performed yielding consistent, high-quality results.  
         SUMMARY AND OBJECTS OF THE INVENTION  
         [0006]    The invention concerns a carrier useable on a movable conveyor for transporting pellet-like objects. The carrier comprises a first jaw portion mountable on the conveyor and having a first surface engageable with the pellet-like object and a second jaw portion mountable on the conveyor in spaced relation to the first jaw portion. The second jaw portion has a second surface substantially facing the first surface and engageable with the pellet-like object. One of the jaw portions is movable toward the other of the jaw portions into a closed position for gripping a pellet-like object between the first and the second surfaces. The one jaw portion is also movable away from the other jaw portion into an open position for releasing the pellet-like object from the carrier. The carrier also includes an actuator for moving the one jaw portion relatively to the other jaw portion between the open and the closed positions at predetermined positions spaced lengthwise along the conveyor.  
           [0007]    The invention also concerns a movable conveyor for transporting pellet-like objects along a path. The conveyor comprises a plurality of carriers for holding the pellet-like objects, the carriers being positioned one behind another and movable along the path, each of the carriers being substantially as described above.  
           [0008]    A method of transporting pellet-like objects along a path is also part of the invention. The method includes the steps of:  
           [0009]    (a) providing a carrier movable along the path and having opposing jaw portions engageable with the pellet-like object, the jaw portions being relatively movable toward one another into a closed position for gripping the pellet-like object and biased away from one another into an open position for releasing the pellet-like object;  
           [0010]    (b) biasing the jaw portions into the open position and loading the pellet-like object onto the carrier between the jaw portions;  
           [0011]    (c) moving the carrier along the path, the path including a portion positioned between predetermined locations spaced lengthwise therealong and traversed by the carrier;  
           [0012]    (d) moving the jaw portions into the closed position while the carrier traverses the predetermined portion of the path between the predetermined locations thereby gripping the pellet-like object between the jaw portions; and  
           [0013]    (e) biasing the jaw portions into the open position after the carrier has traversed the portion of the path between the predetermined locations, thereby releasing the pellet-like object.  
           [0014]    The method may further include the step of performing an operation on the pellet-like object while the carrier is traversing the portion of the path between the predetermined locations where the pellet-like object is securely gripped.  
           [0015]    It is an object of the invention to provide a carrier useable with a conveyor for transporting pellet-like objects.  
           [0016]    It is another object of the invention to provide a carrier for pellet-like objects which grips the pellet-like objects.  
           [0017]    It is still another object of the invention to provide a carrier which grips pellet-like objects and holds them in a consistent position and orientation for performing a processing operation on the pellet-like objects.  
           [0018]    It is again another object of the invention to provide a carrier which ensures consistent, high-quality processing of pellet-like objects.  
           [0019]    It is yet again another object of the invention to provide a carrier which grips pellet-like objects without damaging them.  
           [0020]    It is still another object of the invention to provide a method for processing pellet-like objects consistently and with high quality. 
       
    
    
       [0021]    These and other objects of the invention will be apparent upon consideration of the following drawings and detailed description of preferred embodiments of the invention.  
       BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]    [0022]FIG. 1 is a side view of a machine using carriers according to the invention;  
         [0023]    [0023]FIG. 2 is a perspective drawing of a carrier according to the invention;  
         [0024]    [0024]FIG. 3 is an exploded perspective view of the carrier shown in FIG. 2; and  
         [0025]    [0025]FIG. 4 is a partial sectional view of a portion of the machine shown in FIG. 1. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0026]    [0026]FIG. 1 shows a machine  10  for processing pellet-like objects  12 , shown by way of example as elongated capsules. Machine  10  includes a conveyor  14  formed, for example, from an endless chain  16  which is moved along a path  18  in the direction shown by arrows  19  by sprockets  20  and  22 . The sprockets  20  and  22  are preferably powered by an electric motor (not shown). A plurality of carriers  24  are mounted on the endless chain  16 , preferably one behind the other in the manner of individual articulated links allowing the chain to bend around sprockets  20  and  22 . Carriers  24  hold the pellet-like objects  12  and transport them for processing by the machine as described in detail below.  
         [0027]    Carriers  24  are conducted along path  18  which begins at point  18   a  as the carriers enter a hopper  26  positioned over the path  18 . Hopper  26  holds pellet-like objects  12  in bulk and preferably has an open bottom  28  which allows the carriers  24  to pass through the hopper  26  as they move along path  18  and receive pellet-like objects  12 . Carriers  24  emerge from the hopper  26  at point  18   b  along path  18  with each carrier holding a pellet-like object  12 . The carriers  24  are moved further along path  18  to a processing station  30  mounted on the machine  10  and located along the path  18 .  
         [0028]    Processing station  30  is shown schematically in FIG. 1 and represents any device which performs a desired operation on each pellet-like object. For example, processing station  30  could be a printer for branding the pellet-like objects with a trademark or brand name, a camera for inspecting the objects as they pass or a laser drill for drilling a hole in each object.  
         [0029]    As the pellet-like objects  12  pass through the processing station  30 , the carriers  24  are actuated at a point  18   c  to firmly grip the objects  12  and present them to the station in a consistent position and orientation, without allowing them to move within the carriers  24 . By gripping the objects  12 , the carriers ensure that the operation performed at the processing station will be performed consistently and accurately for each pellet-like object processed. Details of the structure and operation of carriers  24  are described below.  
         [0030]    After passing through the processing station, the pellet-like objects  12  are released from the grip of the carriers  24  at a point  18   d  along path  18 . The pellet-like objects  12  are then deposited into a container  32  at a point  18   e  along path  18 . The carriers  24 , being mounted on an endless chain  16 , move along a return path  34  which takes them back to the hopper  26  where the cycle begins again.  
       Carrier Structure and Operation  
       [0031]    [0031]FIGS. 2 and 3 show a carrier  24  in detail. Carrier  24  comprises a base  36  having an aperture  38  and a slot  40  for mounting the carrier  24  on the endless chain  16  comprising conveyor  14  (see FIG. 4). A fixed jaw portion  42  is mounted on the base  36 , preferably integrally therewith. The fixed jaw portion  42  preferably projects substantially perpendicularly from the base  36 . A movable jaw portion  44  is attached to base  36  in opposition to the fixed jaw portion  42 . Preferably, movable jaw portion  44  is pivotally mounted to the base  36  on a pivot pin  46  and is, thus, pivotable about a pivot axis  48  (FIG. 2) oriented substantially perpendicular to the fixed jaw portion  42 . Other configurations of movable jaw are also contemplated, such as a jaw portion slidable relatively to the other, and a cantilevered jaw portion which is flexible and resilient and capable of being deflected toward the fixed jaw portion.  
         [0032]    Preferably, the movable jaw portion  44  also projects substantially perpendicularly to the base  36 . Each jaw portion  42  and  44  has a respective surface  50  and  52  (FIG. 3) which face one another and are engageable with a pellet-like object  12 , shown in FIGS.  2 - 4  by way of example as a round pill. Surfaces  50  and  52  each have a complementary shape which together substantially conform to the shape of the pellet-like object  12 , thereby allowing the carrier  24  to receive the pellet-like object as it passes through the hopper  26  of machine  10  as described above with reference to FIG. 1.  
         [0033]    Because it is pivotally mounted, the movable jaw portion  44  is pivotally movable relatively to the fixed jaw portion  42  between an open position (identified as  43  in FIG. 4) and a closed position (identified as  45  in the same Figure). In the open position  43 , the surfaces  50  and  52  of the fixed jaw portion  42  and the movable jaw portion  44  are separated from one another by a distance which will allow the pellet-like object  12  to easily be received between the surfaces  50  and  52 . In the closed position  45 , the movable jaw portion  44  is pivoted toward the fixed jaw portion  42  so that the surfaces- 50  and  52  grip the pellet-like object  12  and hold it firmly in a desired position and orientation for presentation to the processing station  30  shown in FIG. 1. The gripping action of the carrier  24  ensures that the pellet-like objects  12  are processed consistently and accurately.  
         [0034]    As shown in FIGS. 2 and 3, movable jaw portion  44  of the carrier  24  has an actuator  54  for moving movable jaw portion  44  relatively to the fixed jaw portion  42 . Preferably, the actuator is in the form of a projection  55  mounted on the movable jaw portion  44  and oriented to extend downwardly, substantially perpendicular to the base  36 . A force applied to the actuator  54  in the direction indicated by arrow  49  perpendicular to and spaced from pivot axis  48  will cause the movable jaw portion  44  to pivot relatively to the fixed jaw portion  42  between the open and closed positions.  
         [0035]    It is preferred to bias the movable jaw portion  44  into the open position by the use of a coil spring  56  positioned between the jaw portions as shown in FIG. 3. Spring  56  is mounted in sockets  58  and  60  in both jaw portions  42  and  44  and acts as a compression spring to normally bias the jaw portions away from one another.  
         [0036]    [0036]FIGS. 1 and 4 illustrate how the carriers  24  are actuated to grip the pellet-like objects  12  as they are transported by the conveyor  14  through the processing station  30 . Chains  16  of the conveyor move between guide rails  62  and  64  (only one of which is shown in FIG. 4) mounted on each side of machine  10 . The guide rails  62  and  64  are arranged in a parallel, spaced relation and define the path  18  which the chain  16  takes in its motion. For most of the path length, the space between guide rails  62  and  64  is empty of obstructions, but along a portion  66  of the path  18 , preferably starting at about predetermined position  18   c  (before processing station  30 ) and ending at about predetermined position  18   d  (after the processing station  30 ), a camming surface  68  is located between the guide rails  62  and  64 .  
         [0037]    As the carriers  24  traverse the path  18  where there are no obstructions between the guide rails  62  and  64 , the jaws  42  and  44  are biased into the open position by the spring  56 . This is desired, for example, as the carriers  24  pass through the hopper  26  because the open position allows the carriers to easily acquire pellet-like objects  12  between the opposing surfaces  50  and  52 . The open position is also desired after processing (point  18   e  along path  18 ) so that the pellet-like objects may be released into the container  32 . However, as the carriers  24  carrying pellet-like objects  12  traverse the portion  66  of path  18  between the predetermined positions  18   c  and  18   d  (which is substantially co-located with the processing station  30 ), they encounter the camming surface  68  positioned between the guide rails  62  and  64  as shown in FIG. 4. Camming surface  68  is positioned beneath the carriers  24  such that it is engaged by actuators  54  which preferably extend downwardly from the movable jaw portions  44  of each carrier. Upon engagement, the camming surface  68  applies an upward force to each actuator  54  as each carrier  24  traverses the portion  66  of path  18 . The force causes the movable jaw  44  on each carrier to pivot into the closed position  45  and firmly grip the pellet-like object  12  between the surfaces  50  and  52 . As long as the actuator  54  engages the camming surface  68  the jaws  42  and  44  will remain in the closed position. Thus, the camming surface  68  is co-located with the processing station  30  between the predetermined positions  18   c  and  18   d  so that the pellet-like objects  12  are securely held during processing. Camming surface  68  is sized in length so that each pellet-like object  12  is gripped before and during the processing step and released only after processing is completed.  
         [0038]    The camming surface  68  is preferably engaged by the tips  72  of the actuators  54 , the actuators being partially hollow and each having a spring biased ball bearing  74  at the tip  72  to facilitate engagement with the camming surface  68  and reduce friction due to the relative motion.  
         [0039]    Camming surface  68  preferably comprises a lead-in surface  76  located so as to initially engage the actuators  54  as they pass the predetermined position  18   c . The lead-in surface  76  is sloped toward the path  18  as shown in FIG. 4. This enables the actuators  54  to engage the camming surface  68  gradually in order to gradually pivot the movable jaw portion  44  into the closed position  45  and grip the pellet-like object  12  gently, avoiding a harsh impact which might damage it. The lead-in surface  76  also helps mitigate wear of the actuators and camming surface by avoiding a sudden impact of actuator against camming surface.  
         [0040]    Camming surface  68  further includes an intermediate surface  77  positioned so as to engage the actuators  54  after the lead-in surface  76 . The intermediate surface  77  is oriented substantially parallel to the path  18  for maintaining constant engagement with the actuators  54  and thereby maintaining the movable jaw portion  44  in the closed position  45  to grip and hold the pellet-like objects  12  while the carriers  24  traverse the intermediate surface  77 . It is most advantageous to perform any processing operations on pellet-like objects  12  while they traverse the intermediate surface  77  because this is where they are held most securely. Preferably, therefore, the processing station  30  is substantially co-located with the intermediate surface  77 .  
         [0041]    Camming surface  68  also includes a lead-out surface  78  positioned so as to engage the actuators  54  after the intermediate surface  77 . The lead-out surface  78  allows the actuators  54  to disengage from the camming surface gradually, preventing the movable jaw portion  44  from snapping open abruptly under the biasing action of spring  56  and possibly catapulting the pellet-like objects  12  from the carriers  24 . The movable jaw portion  44  is biased into the open position  43  upon passing the predetermined position  18   d  along path  18 . This enables the pellet-like object  12  to be released from the carrier, for example, at position  18   e  and be deposited into the container  32 .  
         [0042]    Gripping the pellet-like objects  12  during processing ensures that every one of them will be presented to the processing station in the same relative position and orientation, thus, providing for consistent and accurate processing of each pellet-like object and ensuring a high quality product with fewer rejects and less wastage.