Automated apparatus and method for consolidating products for packaging

An automated apparatus for controlling the automatic packaging of contact lenses in a contact lens fabrication facility includes: a first robotic transfer device for periodically transferring a first predetermined amount of individual packages from an inspection station to an intermediate consolidation buffer and depositing the packages on the consolidation buffer; a control device for tracking and identifying each individual contact lens conveyed from the inspection station to the consolidation buffer and including memory and logic circuits for storing the identity of individual packages containing contact lenses that have been previously determined at the inspection station as being out of specification, and, generating a signal to enable the first robotic device to discard any individual package identified as out of specification; and, a second robotic assembly for periodically transferring a second predetermined amount of individual packages from the consolidation buffer to a second processing station, the control device enabling the first robotic device to provide a sufficient amount of individual packages to the consolidation buffer to enable the second robotic assembly to continuously transfer the second predetermined amount of packages to the second processing station in every period.

FIELD OF THE INVENTION 
The present invention relates generally to the field of manufacturing 
ophthalmic lenses, especially molded, hydrophilic contact lenses, and more 
specifically to an automated apparatus for consolidating contact lenses 
for packaging after inspection thereof. 
DESCRIPTION OF THE PRIOR ART 
The molding of hydrophilic contact lenses is disclosed in U.S. Pat. No. 
4,495,313 to Larsen; U.S. Pat. No. 4,640,489 to Larsen, et al.; U.S. Pat. 
No. 4,680,336 to Larsen et al.; U.S. Pat. No. 4,889,664 to Larsen et al.; 
and U.S. Pat. No. 5,039,459 to Larsen et al., all of which are assigned to 
the assignee of the present invention. 
These prior art references disclose a contact lens production process 
wherein each lens is formed by sandwiching monomer or monomer mixture 
between a front curve (lower) mold section and back curve (upper) mold 
section, carried in a two by four mold array. The monomer is polymerized, 
thus forming a lens which is then removed from the mold sections and 
further treated in a hydration bath and packaged for consumer use. 
U.S. Pat. Nos. 5,080,839 and 5,094,609 disclose respectively a process for 
hydrating contact lenses and a chamber for hydrating contacts lenses 
formed with a monomer or monomer mixtures disclosed in the forgoing 
patents. The process disclosed in these patents significantly reduce the 
thruput time by hydrating the lens and releasing the lens from the mold 
cavity with deionized water and a small amount of surfactant without any 
salts, so that the time consuming ionic neutralization of the polymer from 
which the lens blank is made does not occur during the hydration process. 
When deionized water is used, the final step of the process is to 
introduce buffered saline solution into the final package with the lens 
and then seal the lens within the package so that the final lens 
equilibrium (ionic neutralization, final hydration and final lens 
dimensioning) is accomplished in the package at room temperature or during 
sterilization. 
U.S. Pat. No. 4,961,820, also assigned to the assignee of the present 
invention, discloses a final package for a contact lens, wherein the 
package is formed from a transparent plastic material such as 
polypropylene and a foil laminate that is heat sealed thereto. 
While U.S. Pat. Nos. 5,080,839 and 5,094,609 contemplate that the entire 
hydration process and transfer to final packaging may take place in a 
fully automated fashion, and while the chamber and process described in 
the foregoing patents enabled automated handling of the lens during 
hydration, suitable automated equipment to inspect and handle the lenses 
at high production rates and implement the methods thereof in a fully 
automated apparatus was not readily available or taught by the prior art. 
SUMMARY OF THE INVENTION 
Recent developments in the inspection of contact lenses produced in 
accordance with the foregoing methods has enabled automated lens 
inspection, as taught in U.S. Ser. No. 07/993,756 entitled "Lens 
Inspection Method and Apparatus", (VTN 0037) assigned to the assignee of 
the present invention. Further, recent developments in the hydration and 
automated handling of wet contact lenses, as taught in U.S. Ser. No. 
08/258,556 "Automated Method and Apparatus for Hydrating Soft Contact 
Lenses" (Docket 8998), also assigned to the assignee in the present 
invention, has enabled automatic robotic handling of lenses during 
hydration, and prior to the inspection thereof by the automated lens 
inspection system. 
The removal of lenses, that are out of product specification, from a serial 
product stream of contact lenses generates random variations in the 
product flow which must be consolidated prior to packaging. 
The present invention therefor provides an automated apparatus for 
consolidating serial product flow wherein the product flow includes random 
variations in the flow. The present invention provides a consolidation 
buffer for receiving the serial products from the production line, and 
then consolidating random variations in the product flow. The automated 
robotic handling means then selects a predetermined number and arrangement 
of product units and transports that number and arrangement to a 
subsequent packaging station for packaging, sterilization, and final 
shipment. 
It is further an object of the present invention to provide a robotic 
transfer means for receiving serial product flow, and selectively ejecting 
individual product units in response to data signals from the automated 
lens inspection system. 
It is further an object of the present invention to provide a consolidation 
buffer between two serial production operations, wherein the number and 
arrangement of product varies between input and output. The present 
invention enables use of a first x,y array of product units merging from a 
serial production line, and consolidating those product units into a 
second x,y array of units which corresponds to an array used in second 
production operation relating to the product. 
It is further an object of the present invention to provide a programmable 
logic controller which maintains a status count for each of the individual 
products in the consolidation buffers of the present invention, including 
a count for each random addition of product, and a separate count for each 
selection and transport of product from the buffers to the final packaging 
station. 
It is another object of the present invention to provide a method and 
apparatus for the high speed robotic handling of discrete final packages 
of product having a soft contact lens carried therein. This robotic 
handling enables selective ejection or rejection of specific lenses, even 
when carried in a predetermined X,Y array, when one or more of said lenses 
have been flagged as flawed or out of spec by the automated lens 
inspection system. 
It is another object of the present invention to provide an automated 
control means for sequencing and coordinating each of the robotic 
assemblies used in the transfer of lenses from the automated lens 
inspection system to final packaging. 
While the invention is described with particular reference to molded 
contact lenses wherein the lens has been molded between a first and second 
mold half, as described in U.S. Ser. No. 08/258,654 "Consolidated Contact 
Lens Molding" (Docket 9016) it is understood the present consolidation 
apparatus is equally suitable for the consolidation of lenses formed by 
lathe cutting wherein the hydrogel is maintained at a dry state while the 
desired optical surfaces are cut and polished. Further, the apparatus of 
the present invention may also be used in consolidating spin cast lenses 
which subject a liquid monomer to centrifugal force in a mold which has 
the same shape as the desired optical surfaces of the lens.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
FIG. 1 is a diagrammatic illustration of the automated apparatus of the 
present invention used to consolidate serial product flow when the serial 
product flow has random variations therein. While prefigured 2.times.8, 
2.times.5 and 4.times.8 arrays are used in the description of the present 
invention, it is understood that a variety of arrays and configurations 
may be used in the practice of the invention described herein. 
As illustrated in FIG. 1, an inspection pallet 10 carrying sixteen product 
articles 20, arranged in a 2.times.8 array 20(a) is transported in the 
direction of arrow A from an automated inspection system that has 
separately reviewed each of the products 20 according to a predefined 
product criteria. Pallet 10 travels on a conveyor 12(b) through each of 
the three positions 10(a), (b) and (c) illustrated in FIG. 1. After the 
products have been removed from the inspection pallet 10, as indicated in 
10(c), the empty inspection pallets are returned via return conveyor 13 to 
be refilled with product. 
A robotic handling device 200 is positioned adjacent conveyors 12, 13 and 
has mounted thereon a 2.times.8 vacuum array 202 having sixteen 
independently actuable vacuum gripping means mounted thereon. Pallet 10(b) 
is conveyed along conveyor 12 to a predetermined product pick point, as 
illustrated in FIG. 1 and the 2.times.8 array 202 is positioned thereabove 
to remove each of the sixteen products from the inspection carrier 10(b). 
As illustrated in FIG. 1, products 20(b), (c) and (d) have been marked 
with an "X" to diagrammatically illustrate the removal of flawed or out 
spec products. In the practice of the present invention, a programmable 
logic controller is used to control the various elements of the present 
invention and receives a datablock from the automated inspection system 
having a flag set for each of the products 20(b), (c) and (d) that are 
flawed or out of spec. 
After the products 20 have been removed from the inspection carrier 10(b), 
the robotic transfer device 200 positions the 2.times.8 array over 
conveyor belt 14 and selectively discharges the products 20(b), (c) and 
(d). Those products are then removed by conveyor 14 for subsequent 
destruction or recycling. 
The robotic device 200 then places the remaining products on a vacuum 
consolidation buffer 230 as indicated at 20(d). The product array as 
deposited at 20(d) includes gaps or random variations in the product flow 
resulting from the removal of the out of spec products 20(b), (c) and (d) 
from the serial product flow. The vacuum consolidation buffer 230 includes 
a pair of pneumatic product followers 232, 234 which are used to 
consolidate the product group 20(d) with product group 20(e). Each of the 
pneumatic followers 232, 234 is independently advanced in the direction of 
arrow C until the product stream is consolidated. As product 20(f) 
encounters product 20(g), the entire stream of product driven by product 
follower 232 will advance and trigger an optical sensor 236, which 
generates a control signal for the programmable logic controller to 
de-energize product follower 232 and return the follower to the initial 
start position. Likewise, optical sensor 238 generates a similar return 
signal for product follower 234 when the second product stream has been 
consolidated. After consolidation of the product, a separate indexing 
mechanism 240 returns the entire product stream in the direction of arrow 
D to a predetermined registration point for subsequent robotic handling. 
In the present invention, the consolidation buffer 230 includes a pair of 
vacuum rails which lightly grip the product to permit sliding movement of 
the product along the rails in response to product followers 232, 234, but 
which will prevent "shingling" of the product during consolidation. 
A package feed robotic handling device 300 is positioned between the 
consolidation buffer 230 and a packaging station 400, and is equipped with 
an array 302 which contains ten vacuum gripping means arranged in a 
2.times.5 matrix. The 2.times.5 array 302 is first positioned over product 
group 20(f) and the vacuum gripping means is actuated to withdraw the 
first ten products from the vacuum consolidation rail 230. The packaging 
robotic handling device 300 then positions the 2.times.5 array and product 
group 20(f) over position 1 on the packaging indexing table 400, and drops 
the array of products onto support pallet 410 mounted on the packaging 
indexing table 400. For the purposes of illustrating the operation of the 
invention, only a single support pallet 410 is illustrated on the 
packaging indexing table 400, although it is understood that in actual 
practice eight such support pallets are provided, one for each index 
position. The ten product units 20(g), carried by support pallet 410 are 
then indexed to position 2 for product verification, and to position 3 for 
subsequent product packaging operations. 
During packaging, the packaging index table 400 rotates support pallets 410 
from position to position to enable the products to undergo subsequent 
packaging steps. In the event there is a malfunction or delay in the 
operation of the packaging indexing table 400, the incoming product 
arriving on consolidation buffer 230 is temporarily stored in a buffer 
area 308 which has a plurality of buffer pallets 310 positioned therein. 
When the packaging index table 400 resumes operation, the package robotic 
handling device 300 will then transfer products in the 2.times.5 arrays 
from the buffer pallets 310 to the support pallets 410 on a first-in, 
first-out basis. 
If the product being handled is time sensitive, the programmable logic 
controller can generate a time stamp to be placed with each product array 
as it is transferred from any given processing station to any subsequent 
processing station. Thus, a time stamp may be placed on the product when 
inspected, or when transferred to the buffer area 308. If the product is 
transferred to buffer 308, the X,Y coordinates of the array are also 
stored with the time stamp. If the time sensitive allotment expires before 
packaging index table 400 has resumed operation, the packaging robotic 
handling device 300 will then discard expired time sensitive product, and 
will transfer only product meeting the time sensitive criteria to the 
support pallet 410. Likewise, if a problem in the production line results 
in an inordinate number of products being rejected, so that less than five 
products are available on either consolidation string 230(a), (b) at 
position 20(e) then the robotic handling device 200 will transfer product 
as necessary to balance product streams on both sides of the packaging 
consolidation buffer 230, and thereby enable removal of product as a 
2.times.5 product array. 
POST HYDRATION PROCESSING 
The present invention was designed for and is particularly adapted for use 
in the post hydration processing section of an automated contact lens 
production facility. Contact lenses molded in an automated production 
line, such as that described in copending application U.S. Ser. No. 
08/258,654 entitled "Consolidated Contact Lens Molding"; hydrated in a 
hydration system as described in U.S. Ser. No. 08/181,275, entitled 
"System for Handling Contact Lenses During Hydration"; and automatically 
inspected as described in U.S. Ser. No. 07/993,756 entitled "Lens 
Inspection Method and Apparatus" are particularly well suited for 
consolidation and packaging by the present invention. 
The present invention envisions a multi-purpose disposable lens package 
carrier which transports a contact lens during inspection thereof, and 
serves as a portion of the final packaging after inspection. Package 
carrier 20 is illustrated in FIG. 6 and is formed from injection molded or 
thermal formed plastic sheet material, such as polypropylene and includes 
a planar essentially rectangularly shaped base member 34 having an 
angularly depending wall portion 38 at one end thereof forming a first 
flange member and a pair of registration flanges 33(a), 33(b), one of 
which is visible in FIG. 6, at the other end thereof which are used to 
align the package carrier for robotic handling. This package carrier is 
more fully described in copending application U.S. Ser. No. 995,607, the 
disclosure of which is incorporated here by reference thereto. 
Registration notches 31(a), (b) are provided on either side of the base 34 
to cooperate with registration pins on various support pallets used in the 
processing and packaging operations to register the package carrier and 
lens for further handling or treatment. Offset from the center of the 
package is a cavity 36 integrally formed therein which is of an 
essentially semi-spherical configuration, generally in conformance with a 
curvilinear shape of a contact lens (not shown) which is adapted to be 
stored therein in a sealed condition while immersed in a suitable sterile 
aqueous solution in a manner similar to that described in U.S. Pat. No. 
4,691,820 to Martinez; which is assigned to the assignee of the present 
invention, the disclosure of which being incorporated herein by reference 
thereto. The height "h" of flange member 38 depending from the planar base 
member 34 is complimentary to the height or depth of cavity 36, and 
provides for self alignment of the package carrier in cooperation with 
depending flanges 33(a), (b) on specially configured pallet carriers, as 
will hereinafter be described. Depending flange 38 is also used in the 
final packaging of the product in cooperation with a plurality of 
generally "chevron-shaped" ridges 32, which will assist the end user in 
gripping the package while peeling open a foil laminate cover. 
The cavity 36 also includes a plurality of tick marks 37 which are used to 
assist in holding a contact lens in the centered position in the cavity 
during the removal of deionized water at one of the post hydration 
processing stations. The package carrier is also equipped with an annular 
flange 39 which is used for heat sealing a foil laminate cover in order to 
provide a hermetic seal for the contact lens during final distribution. A 
cut-out 35 may optionally be provided to facilitate gripping the flange 38 
and the package when the cover stock or foil laminate is removed for 
consumer usage. 
Base member 34 also includes a smooth planar surface 34(a) to provide a 
suitable engagement zone for vacuum grippers on the upper side, and a 
vacuum rail on the lower side, which are used to transport the package 
carrier during various stages of the operation. 
An inspection carrier for transporting the package carriers through the 
automated lens inspection system is illustrated in FIG. 7. The inspection 
carrier 10 includes a first and second row 10(a), 10(b) of cavities 40 
which receive the bowl 36 of the package carrier and provide an optical 
sight path for the automated lens inspection system. Each of the 
intermediate registration pins 41 engage a package carrier on either side, 
with the end registration pins 41(a) engaging a single package. These 
registration pins provide for precise registration of the package carrier 
in the longitudinal dimension of the inspection carrier while a pair of 
hard edges 42(a), 42(b) provide a reference surface for the downwardly 
descending flanges 33(a), 33(b), which together with pins 41 register the 
carrier package against rotational skewing. The inspection pallet 10 is 
further provided with three registration openings 43 on either side of the 
pallet which are used to transport the pallet through the automatic lens 
inspection station and to lock the pallet in place during loading and 
unloading of the package carriers. The inspection pallet is further 
provided with a pair of grooves 44(a), 44(b) which provide a positive grip 
for an overhead transport mechanism that places and then removes the 
inspection pallet from the automatic lens inspection system. A pair of 
slanted faces 45 provide clearance for the downwardly descending flange 
member 38 of the package carrier 20. 
As illustrated in FIG. 3, an injection mold machine 30 is used to mold the 
polypropylene package carriers 20 which serve a dual purpose in the 
invention concept. First, to provide a carrier for the inspection of the 
lens by the automated lens inspection system, and secondly, to provide a 
receptacle for the final packaging of the lens for distribution to end use 
consumers. These package carriers are molded in predetermined array, 
typically in clusters of sixteen per mold cycle, and removed from the 
injection mold by a robotic transfer means 60 having a rapidly 
reciprocating low mass transport carrier 62. The carrier 62 includes a 
hand member 64 having a plurality of vacuum gripper means thereon which 
are arranged to correspond to the array of mold cavities within the 
injection molding machine 20. Carrier 62 reciprocates along support member 
26 and is rotatable from a vertical orientation as illustrated in FIG. 3, 
to a horizontal orientation necessary to place the packaged carriers into 
a secondary transfer shuttle 68. Secondary transfer shuttle 68 is used to 
transport a plurality, i.e. sixteen of the package carriers from a first 
receiving position 68(a) illustrated in FIG. 3 to a second position 68(b) 
where the package carriers are picked up by a robotic handling device 50. 
Robotic handling device 50 is articulated, having first and second arms 
51, 52 and a vertically reciprocating arm and hand (not shown) having a 
plurality of vacuum gripping means thereon which engage each of the 
package carriers transported by the transfer shuttle 68. 
The package carriers 20 are then removed from the transfer shuttle 68 and 
placed on an inspection pallet 10 at a pallet loading station 11. In the 
preferred embodiment the package carriers are molded in a 4.times.4 array 
to maximize the efficiencies inherent in such an array for molding, which 
are transported in the inspection pallet 10 in a 2.times.8 array. When 
these two arrays are used, robotic handling device 50 makes two separate 
transfers, and transfers a 2.times.4 array in each transfer. The loaded 
pallet 10 is then moved by conveyor 12(a) to a deionized water injection 
station 16 wherein each of the package carriers transported on the 
inspection pallet are partially filled with degassed and deionized water. 
The inspection pallet is then transferred by a push conveyor 17 to a lens 
loading area 18 where it is batched with a second pallet to provide a 
contiguous loading area with thirty-two package carriers, each of which 
has been dosed with degassed and deionized water. 
A first robotic transfer device 100 having a plurality of convex lens 
carrier elements 110 mounted thereon then removes thirty-two contact 
lenses from the preceding hydration station as described in U.S. Ser. No. 
08/258,556, entitled "Automated Method and Apparatus for Hydrating Soft 
Contact Lenses", (Docket 8998). The robotic transfer device 100 includes 
an adjustable 4.times.8 array 102 of convex lens carriers 104 which pick 
up thirty-two lenses with a first 4.times.8 array, configuration, and 
deposits them in the batched array of thirty-two package carriers at 
staging area 18, with a single lens in each package carrier. The contact 
lenses are transferred from the hydration station to the individual convex 
lens carrier 100 with a gentle puff of air, and retained thereon by 
surface tension. The robotic transfer array 102 is paused at station 70 to 
remove any air bubbles entrapped in the residual deionized water that wets 
the lens. Station 70 includes a plurality of specially configured air 
nozzles which blow off the residual bubbles. 
After the package carriers 20 have been loaded with a contact lens, the 
inspection pallets 10 are singulated by transport push plate 19 and loaded 
onto a first overhead conveyor 21. The overhead conveyor 21 then lifts the 
inspection pallet 10 from the lens loading area and transfers it to the 
automatic lens inspection system 15, and particularly to the conveyor 
15(b) for transport through the automatic lens inspection system. After 
the lenses have been inspected, the inspection pallet is lifted by the 
second overhead conveyor 22 and placed on conveyor 12(b) for transport to 
the deionized water removal station 24. The deionized water is removed by 
a specially configured nozzle, as described in U.S. Ser. No. 07/999,234, 
entitled "Solution Removal Nozzle". The deionized water is used to center 
the lens within the package carrier during the inspection process, but is 
removed prior to packaging, to enable a precise dosing of a buffered 
saline solution in the final package. 
After removal of the deionized water, the lenses, package carriers and 
inspection pallet are transported to the package removal pick point 25 
which clamps the inspection pallet 10 to enable the second robotic 
transfer device 200 to remove the package carriers and lenses therefrom. 
A programmable logic controller maintains a status register for each of the 
lenses as they are placed at the robotic transfer staging area 18 and 
receives a flag from the automatic lens inspection station 15 for each 
lens that has failed inspection. The second robotic transfer device 200 
includes a 2.times.8 array of independently actuable vacuum grippers which 
engage the package carriers at the package removal pick point 25. Any 
packages containing out of spec lenses are then dropped onto conveyor 14 
by the robotic transfer device 200 as hereinbefore described, and the 
remaining lenses are transferred to the consolidation buffer 230 
illustrated in FIGS. 4, 5, 8-12. 
The consolidation buffer 230 includes a pair of vacuum rails 230(a), (b), 
cross sections of which are illustrated in FIG. 12, which receive the 
2.times.8 array of package carriers from the second robotic transfer means 
200. This 2.times.8 array is deposited on the consolidation buffer 230 at 
position 230(c), as illustrated in FIG. 5. A pair of product followers 
232, 234 engage the string of package carriers and slide them in the 
direction of arrow C until they engage other package carriers on the 
consolidation buffer, or until they trigger light sensors 236, 238 as 
previously described. If they encounter existing package carriers, the 
followers 232, 234 push the entire string in the direction of arrow A 
until the string of package carriers has triggered light sensors 236, 238 
illustrated in FIG. 1. At this point, the PLC logic controller signals a 
pneumatic controller which reverses the actuating air pressure for the 
product followers 232, 234 causing them to withdraw. A product indexing 
pusher 240 then returns the product string in the direction of arrow D to 
a fixed reference position where the package carriers can be readily 
engaged by the third robotic handling device 300. The vacuum consolidation 
rails 230 exert a slight downward pressure on each of the package carriers 
on the smooth planar area 34(a) to hold the package carriers tightly to 
the rail and to prevent shingling thereof when being driven forward by 
product followers 232, 234, or indexing pusher 240. 
The packaging robotic transfer device 300 includes a 2.times.5 array 302 of 
vacuum gripping means 304 which may engage ten of the package carriers at 
the position illustrated at 230(d) in FIG. 5 for transfer to the indexing 
turntable 400. The indexing turntable 400 includes a rotatable turntable 
having eight support pallets 410 mounted thereon for receiving the 
2.times.5 array of package carriers and contact lenses from the packaging 
robotic transfer device 300. 
In normal operation, the robotic transfer device 300 deposits the 2.times.5 
array on support pallet 410 in the number 1 position. If the indexing 
turntable is not in operation, a large buffer area 308 is provided with a 
plurality of buffer pallets, one of which is indicated symbolically at 310 
in FIG. 5. Buffer area 308 will accommodate approximately fifty pallets 
for intermediate storage, or approximately 10 minutes of product stream in 
the event the packaging operation is temporarily interrupted for resupply, 
maintenance or adjustments. 
After the 2.times.5 array of package carriers has been deposited on support 
pallet 410, the pallet is rotated to position 412 where optical sensors 
verify that a package has been loaded at each position and that the 
packages are correctly aligned on the pallet. Indexing turntable 400 is 
then rotated again to station 414 wherein each of the individual package 
carriers are dosed with approximately 950 microliters of a buffered saline 
solution. The use of deionized water in the hydration and inspection steps 
significantly speeds the production line as a whole since the time 
consuming ionic neutralization of the polymer from which the lenses are 
made does not occur until after the inspection process. When deionized 
water is used for hydration and inspection, the final step of the process 
is to introduce buffered saline solution into the final package with the 
lens and then seal the lens within the package so that final lens 
equilibration (ionic neutralization, final hydration and final lens 
dimensioning) is accomplished in the package at room temperature or during 
sterilization after the lens has been packaged and sealed. 
It has been determined empirically that it is desirable that soft contact 
lenses produced in accordance with the present invention be exposed to 
atmosphere for no more than sixty minutes between the removal of the 
deionized water at station 24 (illustrated in FIG. 3) and the dosing of 
the saline solution at station 414 in FIG. 5. The programmable logic 
controller which previously received the inspection results from the 
automated lens inspection system and correlated those results to the 
individual lenses, also time stamps the individual lenses at the pick up 
point 25, immediately following the removal of the deionized water at 
station 24. This time stamp is transferred through consolidation and into 
the 2.times.5 array when removed by the packaging robotic transfer device 
300. In the event the indexing turntable 400 is not operational, and the 
2.times.5 array is stored in the buffer 308, then the X,Y coordinates of 
the 2.times.5 array are stored with the time stamp to enable the packaging 
robotic transfer device 300 to select "fresh" product, i.e. less than 
sixty minutes old, at the time the indexing turntable 400 resumes 
operation. After operation is resumed, the robotic transfer device 300 
will then dispose of the "expired" product, rather than transferring it to 
the indexing turntable. 
After saline dosing at station 414, the saline level is checked at station 
415 and the support pallet is then rotated under a final product check 
station 416 to a foil receiving station 418. 
As described earlier, each group of package carriers 20 receives a single 
laminated foil cover sheet which is heat sealed to the package carriers. 
The lens package is more fully described in U.S. Ser. No. 08/146,754, 
entitled "Packaging Arrangement for Contact Lenses", also assigned to the 
assignee of the present invention, the disclosure of which is incorporate 
herein by reference thereto. The laminated foil stock 432 is fed from a 
large indefinite spool through a tensioning device 434 to an ink jet 
printer 436 which prints the lot, batch and power number of the lenses to 
be packaged. The foil laminate is cut from an indefinite length product 
into two strips that are heat sealed to the 2.times.5 product array to 
provide two separate 1.times.5 product strips. The foil in between each of 
the package carriers is also partially severed, scored or perforated to 
enable the consumer to separate individual packages from the 1.times.5 
array at the time the product is used. The partial scoring is done with a 
series of rolling blades 440(a)-(d) which are pneumatically biased into a 
drum 439. The foil is then split into two strips by a foil slitter blade 
441 and the foil passes through a stationary gripper and sensing mechanism 
442. A video camera 438 and a series of sensors at station 442 are used to 
provide precise alignment of the information printed by the ink jet 
printer 436, with the printing fields into which said printing is placed, 
and the alignment of the perforations or scores provided by rolling blades 
439. An advancing gripper 434 is provided to draw a length of foil 
laminate corresponding to the 1.times.5 array and sever the strips with a 
rotating knife 444. At the completion of this cut, the advancing gripper 
434 has advanced in the direction of arrow E in FIG. 4 to place the 
1.times.5 foil strips under vacuum gripping heads 418(a), (b). These 
vacuum gripping heads then reciprocate downwardly to grip the foil, lift 
it from the advancing and cutting station 434, and transfer the foil to 
the indexing turntable 400 at the foil placement station 418. 
The indexing turntable 400 is then rotated again, and a heat seal mechanism 
420 seals a single strip of foil to five separate package carriers in a 
single high temperature short cycle sealing operation. Indexing turntable 
400 is then rotated to position 422 where a reciprocating transfer head 
446 removes the sealed product from the indexing turntable 400 and 
transports it in the direction of arrow F for sterilization and cartoning. 
The Consolidation Buffer 
The vacuum consolidation buffer of the present invention will be described 
with respect to FIGS. 8-12 in which 230(a), (b) represent a pair of 
elongated vacuum rails defined by housing members 231(a), (b) which 
enclose vacuum plenums 242(a), (b) and which define a plurality of vacuum 
slits 244(a), (b). While a single elongated slot 244(a), (b) is depicted 
in FIG. 12, and a plurality of slots are depicted in FIG. 8, it is 
understood that a variety of aperture shapes and arrangements could be 
used. As illustrated in FIG. 12, the second robotic transfer device 200 
includes a 2.times.8 array 202 of independently actuable vacuum gripping 
means 204 which pick a 2.times.8 array of package carriers from pick point 
25, immediately following the removal of the deionized water as previously 
described with respect to FIG. 3. The 2.times.8 array is then moved to 
position 230(c) as illustrated in FIG. 5, and as illustrated in 
cross-section in FIG. 12 wherein the individual package carriers 20 are 
positioned immediately above the vacuum rail, and then lowered into 
engagement therewith, to enable the vacuum slits 244(a), (b) to engage the 
smooth planar surface 34(a) of the package carrier 20. The vacuum gripping 
means 204 are then released and the package carriers 20 are then lightly 
gripped and secured to the consolidation buffer vacuum rails 230(a), (b) 
by a vacuum drawn through plenum 242(a), (b). The purpose of the vacuum 
rail is to prevent shingling of the individual carrier packages when long 
strings of the packages are moved by the product followers 232, 234. Each 
of the vacuum rails 230(a), (b) also define an elongated trough 246(a), 
(b) which receives the bowl of the package carrier 20 and product guides 
250(a ), (b) which prevent lateral movement of the package carrier as they 
are slid along the vacuum rail. After the package carrier 20 has been 
seated on the vacuum rail as illustrated in FIG. 9, the package followers 
232, 234 advance the respective strings of product or package carriers 
along the vacuum consolidation rail 230(a)(b) in the direction of arrow C 
in FIG. 8. As illustrated in FIG. 8, the product followers 232, 234 are 
mounted on pneumatically driven carriages, one of which is visible in 
elevation view of FIG. 8 and two of which are visible in plan view in FIG. 
10. The carriage includes a rodless cylinder 250 mounted for reciprocation 
on pneumatic cylinder 252 and guided by guide rod 251. The product 
followers 232, 234 are each mounted to the respective carriages by virtue 
of a pair of parallel rods 254(a), (b), 254(c), (d) which are mounted for 
reciprocation within housings 250(a), (b). The product followers 232, 234 
are biased into engagement with the carriage members 250(a), (b) by means 
of springs 256. 
The product string is advanced in the direction of arrow C until they 
trigger one or both of the optical sensors 236, 238. When the optical 
sensors are triggered, the programmable logic controller reverses the 
pneumatic bias on rodless cylinder 252 and the carriage 250 is then 
retracted to its original position as illustrated in FIG. 8. In addition, 
a proximity sensor (not shown) at the end of the stroke will also generate 
a signal to reverse the direction of carriage 250 if no product has been 
deposited on either of the consolidation buffer rail 230(a), (b). 
After the respective product streams have been advanced from position 
230(c) to the optical sensor 238, a product indexing mechanism 240 is 
actuated to return the product string to a predetermined location for 
registration with the third robotic transfer device 300 which transfers 
product onto the packaging indexing table 400. The product indexing 
mechanism 240 includes a pneumatic cylinder 264 which retracts a push rod 
266 and a pusher plate 262 into engagement with the product stream on the 
vacuum consolidation rail. The product pusher arm 262 then returns the 
leading edge of the first package carrier on each vacuum rail to a 
predetermined index position for registration with the 2.times.5 array 302 
mounted on the packaging robotic transfer device 300. 
While the invention has been particularly shown and described with respect 
to the preferred embodiments thereof, it will be understood by those 
skilled in the art that the foregoing, and other changes in form and 
details, may be made therein without departing from the spirit and scope 
of the invention, which is limited only by the scope of the following 
claims.