Transfer conveyor system for use between sterile and non-sterile environments

A sterile product packaging system includes a bottle filling/stoppering machine housed within a sterile environment and a bottle capping machine housed within a non-sterile environment separated by a partition wall from the sterile room. Each of the filling/stoppering machine and capping machine has a belt conveyor associated therewith for moving bottles to and from the machines, each belt conveyor residing entirely within the respective sterile and non-sterile rooms. A transfer conveyor system is provided to transfer bottles from the filling/stoppering machine belt conveyor, through the opening in the partition wall, to the capping machine belt conveyor. The transfer conveyor system includes a lead screw formed of an elongated shank having a continuous spiral thread along its length. A transfer plate overlaps the ends of the two belt conveyors, and is situated beneath and substantially contiguous with the lead screw. The spiral thread of the lead screw has a bottle-engaging root configured to engage a bottle between the lead screw and a guide bar opposite the lead screw. Bottles are pushed from the filling/stoppering machine conveyor belt onto the transfer plate and conveyed along the length of the lead screw as the spiral thread rotates to exit the lead screw onto the capping machine conveyor. The lead screw transfer conveyor system prevents cross-contamination between the sterile and non-sterile environment.

BACKGROUND OF THE INVENTION 
The present invention concerns a transfer conveyor system for use between a 
sterile or "clean" room and a relatively non-sterile room in a sterile 
product packaging system. In one specific aspect, the invention concerns a 
transfer conveyor system for conveying bottles from a filling/stoppering 
machine in a sterile room to a capping machine in a non-sterile room, 
while minimizing the potential for cross contamination caused by the 
transfer conveyor system. 
Most modern packaging systems are mechanized with electrically controlled 
conveyors used to transfer containers between packaging stations. For 
example, controlled conveyors transfer containers to a station in which 
the containers are filled and from there to a separate station in which 
the containers are closed, after which the container is discharged. Bottle 
containers are particularly well suited for this mechanized approach to 
filling and closing. In some industries, it is essential that certain of 
the packaging operations occur in a sterile or "clean" environment. One 
such field concerns medicines or drugs which are subject to regulation by 
the Food and Drug Administration. In this industry, the filling/stoppering 
operation is typically conducted in a sterile room to avoid contamination 
of medicine or drug. Other steps of the packaging process, such as closing 
the container, need not occur in the sterile environment. 
Referring now to FIG. 1, a diagramatic view of a sterile product filling 
and bottle capping system 10 is depicted to illustrate one such typical 
system in the industry. For such a system 10, an input conveyor 11 
continuously provides containers, such as bottles, to a filling/stoppering 
machine 12. The filling/stoppering machine resides within a sterile room 
13. Alternatively, the source of bottles may also reside within the 
sterile room 13. At the filling/stoppering machine 12, the empty and 
sterilized bottles are filled with a medicine or drug and then stoppered. 
The newly filled and stoppered containers are passed by way of a transfer 
conveyor 14 to a capping machine 15. As illustrated, the capping machine 
15 is housed within a relatively non-sterile room. The capping machine 15 
engages a closure to the newly filled bottles and passes the final product 
to a discharge conveyor 17. 
In many prior systems, such as the system 10, the transfer conveyor 14 
includes a continuous belt-type conveyor that extends between time 
filling/stoppering machine 12 and the capping machine 15. One significant 
drawback of using a continuous belt conveyor is that the belt passes from 
the sterile to time non-sterile environment and then returns to the 
sterile room, presenting a significant risk of a contaminated belt 
returning into the sterile room. Thus, the use of a belt conveyor as time 
transfer conveyor 14 between sterile and non-sterile rooms may 
substantially defeat the purpose of segregating time two environments. 
Another approach in time industry has been to perform all of the packaging 
operations in a sterile environment. Thus, the filling/stoppering machine 
and capping machine would both be situated within the sterile room. In 
this arrangement, only the final product leaves the sterile room, thereby 
significantly eliminating the risk of contamination of the medicine or 
drugs contained therein. Although this approach may provide the greatest 
security against contamination, large sterile environments are difficult 
and expensive to maintain. Housing all of the packaging machinery in a 
sterile environment increases the size of the room required to house all 
the equipment, which likewise increases the requirements for the 
sterilization system. 
What is needed in the industry is a sterile product packaging system which 
provides time greatest security against contamination of the product, such 
as medicines or drugs, without incurring the expense of an enlarged clean 
room. In addition, this system would optimize the requirements of 
maintaining a sterile room so that only the essential step of filling the 
container with sterile product and stoppering need be performed in a 
sterile environment, leaving the remaining steps of the packaging system 
to be conducted in non-sterile environments. 
SUMMARY OF THE INVENTION 
The present invention contemplates a sterile product packaging system which 
includes a filling machine and stoppering machine housed within a sterile 
environment, and a subsequent machine for sealing the packaging housed 
within a non-sterile environment. In a preferred embodiment, the packages 
are bottles, the filling/stoppering machine is used to fill the bottles 
with sterile medicine or drugs, and the final packaging step is performed 
at a bottle capping machine. In one important aspect of the invention, a 
transfer conveyor system is provided between the sterile 
filling/stoppering machine and the non-sterile capping machine. The 
transfer conveyor system extends through an opening in a wall dividing the 
two environments. 
In a preferred embodiment of the invention, the transfer conveyor system 
extends from the sterile room to the non-sterile room and includes a lead 
screw which is formed of an elongated shank having a continuous spiral 
thread along its length. The transfer conveyor system also includes a 
transfer plate which overlaps the ends of a first belt conveyor leaving 
the filling/stoppering machine in the sterile room and a second belt 
conveyor entering the capping machine in the non-sterile room. With this 
arrangement, neither of the belt conveyors extends through the opening in 
the dividing wall. The transfer conveyor system, and particularly the lead 
screw transfer plate, provides the only means for transferring bottles 
between the two environments. 
The lead screw, and particularly the spiral thread, provides a 
bottle-engaging root which is configured to engage a bottle between the 
lead screw and a guide bar opposite the lead screw. In this manner, 
bottles are grabbed from the conveyor leaving the filling/stoppering 
machine and are conveyed along the length of the lead screw as the spiral 
thread rotates. The bottles then exit the lead screw at its last spiral 
thread and are picked up by the conveyor which carries the bottles to the 
capping machine in the non-sterile environment. 
One object of the invention is to provide a transfer conveyor system which 
is readily adapted for use between product packaging machines positioned 
in sterile and non-sterile environments, respectively. Another important 
object is to provide such a conveyor system that substantially avoids or 
minimizes the risk of contamination of the sterile environment. 
A further object of the present invention resides in a transfer conveyor 
system which can be easily mated with control systems used in controlling 
the container packaging machinery. Other objects and certain benefits of 
the present invention will become obvious from the following written 
description and accompanying figures.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
For the purposes of promoting an understanding of the principles of the 
invention, reference will now be made to the embodiment illustrated in the 
drawings and specific language will be used to describe the same. It will 
nevertheless be understood that no limitation of the scope of the 
invention is thereby intended, such alterations and further modifications 
in the illustrated device, and such further applications of the principles 
of the invention as illustrated therein being contemplated as would 
normally occur to one skilled in the art to which the invention relates. 
Referring again to FIG. 1, a sterile product packaging system 10 is shown 
as including a filling/stoppering apparatus 12 in a sterile room 13, and 
filled and stoppered containers are provided to a closure apparatus 15 in 
a non-sterile room 16. In one embodiment, the containers are glass vials 
or bottles, the bottles are filled and stoppered, and the closure 
apparatus is a bottle capping machine. 
In accordance with the present inventions, the transfer between the 
filling/stoppering machine 12 and the capping machine 15 is performed by a 
transfer conveyor system 20 as illustrated in FIG. 2, the transfer 
conveyor system 20 extends through an opening 24 in partition wall 22 
which divides the sterile room 13 and the non-sterile environment 16. 
Bottles are received by the transfer conveyor system 20 from the 
filling/stoppering machine by way of a filling/stoppering machine conveyor 
means 26. Similarly, the transfer conveyor system passes bottles through 
the opening 24 onto a capping machine conveyor means 28, which then 
carries the bottles to the capping machine 15. 
In the preferred embodiment, as in typical systems in the medicine and drug 
product industry, both the filling/stoppering machine conveyor means 26 
and the capping machine conveyor means 28 comprise a continuous belt-type 
conveyor. In an important aspect of the invention, neither conveyor means 
26 or 28 passes through the opening 24 in the dividing wall 22 so that the 
belts of the respective conveyor means cannot carry contaminants into the 
sterile room 13. 
In the sterile room, a bottle sensor 27 determines whether a number of 
bottles B are backed up on the respective filling/stoppering conveyor 
means 26. Likewise, a similar bottle sensor 29 is provided in the 
non-sterile room to determine whether bottles are backed up prior to entry 
into the capping machine 15. Both sensors are used to control the rate and 
timing of operation of their respective associated conveyor means, or 
associated filling/stoppering machine 12 and capping machine 15. For 
example, if the bottle sensor 27 detects a bottle directly underneath the 
sensor situated on the conveyor means 26, a signal is sent to the 
filling/stoppering machine 12 to place the machine at idle so that it does 
not pass further filled bottles onto the conveyor means 26. Likewise, the 
bottle sensor 29 determines whether the capping machine 15 is having 
trouble keeping up with the flow of bottles from the filling machine. In 
this instance, the bottle sensor 29 at the capping machine end of the 
system will place the capping machine conveyor means 28 in an idle 
condition until the slowdown at the capping machine has been resolved. In 
the preferred embodiments, both bottle sensors 27 and 28 are integrated 
into a complete control system for both the filling/stoppering machine 12 
and capping machine 15, as well as the transfer conveyor system 20 itself. 
In the preferred embodiment, the transfer conveyor system includes screw 
conveyor means 30 which extend through the opening 24 between the two 
conveyor means 26 and 28. In particular, the screw conveyor means 30 
overlaps a portion of the outlet or discharge end of the 
filling/stoppering machine conveyor means 26 and extends through the 
opening 24 to overlap a portion of the inlet end of the capping machine 
conveyor means 28. In accordance with the present invention, the screw 
conveyor means 30 is the only component of the sterile product packaging 
system that passes between the sterile and non-sterile environments. 
However, as will become apparent from the following description, no 
component of the screw conveyor means 30 moves from the non-sterile room 
to the sterile room, thereby greatly minimizing the risk of contamination 
of the sterile room 13. 
The screw conveyor means 30 includes a lead screw 32 as shown in FIGS. 2 
and 3. The lead screw 32 comprises an elongated shank 33 onto which a 
continuous spiral thread 34 is formed. The root 36 of the spiral thread 34 
is adapted to engage a bottle between adjacent thread tips 37 at 
essentially the root diameter of the lead screw 32. The spiral threads 34 
of the screw 32 can be formed in the configuration of a typical lead screw 
or worm-type gear. The manner in which the lead screw 32 engages the 
bottle B is shown more particularly in the detail view of FIG. 4. In that 
figure, it can be seen that the bottle B is retained between thread tips 
37 in the recessed root 36 of the lead screw. Rotation of the lead screw 
in the direction of the arrow R causes the spiral threads to push the 
bottle B in the direction D. 
The lead screw 32 includes a drive spindle 38, as shown at the left end of 
the screw in FIG. 3, and a support spindle 39, at the right end of the 
lead screw. The drive spindle 38 is connected to a drive motor 40 by way 
of a gear box 41. The support spindle 39 is rotatably mounted in an end 
bearing support 43. The lead screw 32 is carried by a frame 45, and more 
particularly, the gear box 41 and the end bearing support 43 are mounted 
at opposite ends of the frame 45. A mounting bracket assembly 46 is 
provided to support the frame on existing structure associated with either 
the filling machine 12 or capping machine 15. In the preferred embodiment 
depicted in FIGS. 2 and 3, the mounting bracket assembly 46 is situated in 
the sterile room and is suitably attached to framework associated with the 
filling machine in a manner that will be readily known to persons of 
ordinary skill in this art. 
Further details of the transfer conveyor system are shown in FIG. 5. In 
particular, it can be seen that the system includes a transfer plate 48 
supported by the frame 45 and mounting bracket assembly 46, and projects 
horizontally outward from beneath the lead screw 32 so that the lead screw 
overlaps a longitudinal edge of the plate. The transfer plate 48 is wide 
enough to support a bottle thereon when the bottle is disposed between 
thread tips 37 of the lead screw. 
As shown in FIG. 3, the transfer plate resides directly above and in close 
proximity to the filling machine conveyor belt 26 and the capping machine 
conveyor belt 28. The plate is generally contiguous with although somewhat 
shorter than the lead screw, as shown in FIG. 3. More particularly, the 
transfer plate 48 begins after preferably two windings of the spiral 
thread 34 on the lead screw 32. By retracting the leading edge of the 
transfer plate 48 from the end of the lead screw 32, bottles can be 
engaged by at least one turn of the spiral thread 34 when the bottles are 
still on the conveyor belt, thereby providing a smooth transfer of the 
bottles onto the plate 48. Similarly, at the discharge end of the lead 
screw 32, the transfer plate 48 terminates prior to the end of the lead 
screw, axed preferably prior to about one turn of the spiral thread 34. In 
the same manner, the rotation of the lead screw will push bottles off the 
transfer plate 48 onto the capping machine conveyor means 28 moving 
beneath time plate. 
The transfer plate ,18 preferably includes a leading edge bevel 49 which 
further facilitates the passage of bottles between the conveyor belt 26 to 
the transfer plate 48. In addition, a trailing edge bevel 50 may be 
provided at the opposite end of the plate to provide a smooth transition 
of bottles from the plate onto the capping conveyor belt moving beneath. 
As shown in FIGS. 2 axial 3, the transfer plate 48 spans the gap between 
the ends of the two belt conveyors 26 and 28, extending through the 
opening 24 in partition wall 22. 
Referring back to FIG. 5, it can be seen that the mounting bracket assembly 
46 also includes an adjustment plate 52. A pivot mount 53 is provided on 
the adjustment plate 52 for pivotable attachment of the frame 45 thereto. 
The adjustment plate 52 includes a guide slot 54 through which a fixation 
means 55 extends. The fixation means is mounted to the frame 45 and 
provides means for adjustably fixing the frame to the adjustment plate 52 
at the guide slot 54. The mounting bracket assembly 46, and particularly 
the pivot mount for the frame 45, allows the location of the lead screw 32 
to be varied with respect to the transfer plate 48. Thus, the entire 
transfer conveyor system 20 can be adjusted to account for different sizes 
of bottles passing between the filling and capping stations. For example, 
bottles having a larger diameter or a greater height may require that the 
gearbox 41 and frame 45 be pivoted in the clockwise direction depicted in 
FIG. 5 in order for the lead screw to engage the bottles without jamming. 
The details of the gearbox 41 are shown in FIG. 5. In particular, the motor 
40 includes a drive pinion 58 which extends into the gearbox. A cluster 
gear arrangement 59 is rotated by the drive pinion 58 to ultimately rotate 
the drive spindle 38 of the lead screw 32. The cluster gear arrangement 59 
can be modified as required to provide the optimum gearing between the 
motor 40 and the lead screw 32. In addition, clockwise or 
counter-clockwise rotation of lead screw can be accomplished, for example, 
by modifying the gear arrangement 59 or by reversing the motor. 
In a further aspect of the transfer conveyor system 20, a guide bar 62, as 
shown in FIGS. 2 and 5, is provided opposite the lead screw 32. As shown 
more specifically in FIG. 5, a bottle B is disposed between the lead screw 
32 and the guide bar 62 so that it cannot slip off the plate 48. An 
upstream guide bar 64 is provided opposite guide bar 62 between the 
filling machine and the transfer conveyor system 20. Likewise a downstream 
guide bar 65 is also provided between the conveyor system 20 and the 
capping machine. The combination of the guide bar 62 with the two upstream 
and downstream guide bars, 64 and 65, respectively, properly guides the 
bottles that are traveling on the two conveyor means 26 and 28. 
As discussed above, the sterile product packaging system 10 includes a pair 
of bottle sensors 27 and 29. These bottle sensors control the operation of 
their respective filling/stoppering machine 12 and capping machine 13. In 
addition, the transfer conveyor system motor 40 can be controlled by 
either or both of the sensors 27 and 29. Specifically, if for example 
sensor 29 detects a backup at the capping machine, a signal can be sent to 
control both the capping machine conveyor means 28 and the lead screw 
drive motor 40 to stop or idle these particular conveyor components. Once 
the backup is resolved at the capping machine, a further signal from the 
bottle sensor 29 can direct the drive motor 40 for the transfer conveyor 
system 20 to continue. In a similar manner, the bottle sensor 27 for the 
filling machine may also control the lead screw drive motor 40. 
While the invention has been illustrated and described in detail in the 
drawings and foregoing description, the same is to be considered as 
illustrative and not restrictive in character, it being understood that 
only the preferred embodiment has been shown and described and that all 
changes and modifications that come within the spirit of the invention are 
desired to be protected. 
For example, the lead screw 32 can be formed of a single molded piece. 
Alternatively, Lime drive spindle 38 for the lead screw 32 may extend 
throughout the entire length of the screw suitably fixed in a bore within 
the shank 33 so that the lead screw rotates with the drive spindle. It is 
further understood that the drive spindle 38 and support spindle 39 can be 
mounted within a bearing or bushing arrangement at either end of the lead 
screw. 
The drive motor 40 can be sized according to the speed requirements for the 
system. Preferably the motor is a variable speed motor which can be 
electrically tied to the speeds of either or both of the filling machine 
and capping machine. In one specific embodiment, a COMPUMOTOR* motor, sold 
by Compumotor Corp, is utilized which is controlled by a sequencing 
program in an electronic system controller. In this specific embodiment 
the motor is an electronic stepping motor which is synchronized to a 
master pulse generated by a shaft encoder on either the capping machine or 
on the capping machine conveyor. 
In another aspect not specifically depicted in the figure, a laminar flow 
hood can be provided directly above the discharge end of the lead screw 
32. This laminar flow hood will provide a further degree of isolation 
between the sterile and non-sterile environments by drawing air across the 
conveyor components in a known manner.