Apparatus for closing a container

The container closure and sealing apparatus includes opposed and oppositely rotating screw feeders for moving the containers from the feed conveyor to tacking apparatus which exerts sufficient force on a tape of pre-punched covers to dislodge a cover from the tape and temporarily secure the cover to the container. An infeed indexing apparatus works in timed coordination with the tacking apparatus and with the heat sealer to remove the containers from the screws and deposit the containers onto the heat sealer where localized heat is applied to the container and cover to perform the permanent sealing and securing of the cover to the container. The heat sealer transports the containers to an indexing ejector which works in timed relationship therewith to move the containers from the heat sealing assembly to a discharge conveyor.

BACKGROUND OF THE INVENTION 
This invention relates generally to improved apparatus for sealing and 
closing the open tops of containers. 
More particularly, but not by way of limitation, this invention relates to 
an improved apparatus for closing and sealing the open top of a container 
with a cover having a heat responsive, adhesive polymer thereon. 
Various types of apparatus have been proposed in the past for closing the 
open tops of containers. In some instances, the upper or open end of the 
container has been provided with a flange over which the cover is crimped 
when the cover is constructed from a material such as aluminum foil. In 
other instances, apparatus has been provided wherein the cover is spin 
welded, such as when a thermoplastic material is used for the cover. At 
times, the cover is attached to the container by some form of adhesive 
disposed between the cover and the container. Various degrees of success 
have been attained by the apparatus previously utilized. 
This invention provides improved apparatus for sealing the open tops of 
such containers wherein it is immaterial whether the flange is provided 
about the periphery of the open end of the container or not and wherein it 
is immaterial what material is utilized to form the cover. To this end, 
the open end of the container is sealed by a cover that has an adhesive 
placed on the cover that will form a bond with the container. 
It is an object of this invention to provide improved apparatus that 
provides a means for closing and sealing such containers at a high rate of 
speed and with great dependability. 
SUMMARY OF THE INVENTION 
Accordingly, this invention provides improved apparatus for closing and 
sealing the open top of a container with a cover having a heat responsive 
adhesive polymer thereon, the apparatus comprises: a housing; container 
feed means on the housing for receiving the containers and for positioning 
each container; cover applying means for locating a cover on each 
positioned container to close the open top; container discharge means; 
and, means for activating the adhesive polymer including means for moving 
the container from the container feed means to the discharge means.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the drawing in FIGS. 1 and 2 in particular, shown therein and 
generally designated by the reference character 10 is apparatus 
constructed in accordance with the invention for closing and sealing the 
open end of containers. As illustrated, the apparatus 10 includes a base 
or housing 12 having the following apparatus therein: a feed conveyor 
apparatus 14, a tacking assembly 16, a cover feed and punching mechanism 
18 and indexing feeder 20 (See FIG. 2), a heat sealing assembly 22, an 
indexing assembly 24 and a discharge conveyor 26. 
In FIGS. 1, 2 and 3, it can be seen that the infeed conveyor apparatus 14 
includes a feed conveyor mechanism 28 having a plurality of containers 30 
thereon. The containers 30 are being directed into a pair of opposed and 
oppositely arranged feed screws 32 that function in timed relationship 
with the tacking assembly 16 so that the feet or pads 34 on the tacking 
assembly 16 are aligned with the containers 30 as they pass thereunder. 
In FIG. 5, there is an enlarged illustration of a cover tape 36 which 
includes a plurality of prepunched covers 38. The covers are punched in 
the aluminum foil tape 36 and retained therein by a plurality of small 
tabs 40. Also, the covers 38 are coated adjacent to their periphery with 
an adhesive 42. The adhesive 42 is desirably Ethylene Vinyl Acetate if the 
containers 30 are manufactured from a plastic material such as 
polypropylene, polyethylene or polyethylene terephthalate. It is preferred 
that the adhesive 42 be one that is activated when heat is applied thereto 
to securely close and seal the containers 30. The tape 36 may of course, 
be of any desirable material, but for many applications, aluminum foil has 
proved to be entirely satisfactory. 
A blank aluminum foil 43 tape can be seen in FIG. 1 extending from a roll 
into the cover feed and punching mechanism 18. The tape 43 is routed 
around the apparatus 18 by a plurality of idlers to a punching roll 46 
where the tape 43 is punched to form the tape 36 having covers 38 punched 
therein as shown in FIG. 5. The prepunched tape 36 is then fed into the 
tacking apparatus 16. As the tape 36 passes through the apparatus, the 
pads 34 in the tacking assembly 16 exert enough force downwardly on the 
tape 36 and upon the containers 30 to dislodge the covers 38 from the tape 
36 and temporarily secure the covers 38 to the containers 30. The tape 36 
with the covers 38 punched therefrom is then reeled onto a reel 47 from 
which the punched out tape is removed for disposal. 
The indexing feeder 20 engages each of the containers 30 (See FIG. 2) as 
they come out from under the tacking assembly 16 and out of the feed 
screws 14. The indexing feeder 20 rotates in such a manner as to position 
each of the containers 30 on the heat sealing assembly 22 under one of the 
pistons 48 carried thereby. 
The heat sealing assembly 22, or at least a portion thereof, is rotating in 
timed relationship with the indexing feeder 20 to move the containers 30 
from the indexing feeder to the indexing ejector 24. The pistons or 
plungers 48 on the heat sealing assembly 22 move downwardly to engage the 
covers 38 located on the upper end of the containers 30. 
As illustrated in FIG. 4, the plunger 48 deforms the peripheral edge of the 
cover 38 downwardly over the outside of the container 30. Heating 
electrodes or other suitable heating means 50 is located in the plungers 
48 and, when activated, causes local heating of the cover 38 and of the 
adhesive 42 thereon so that the cover 38 adheres to and seals the upper 
open end of the container 30. The traverse time in the heat sealer is 
designed to provide total and complete sealing of the containers 30. 
Upon reaching the indexing ejector 24, the containers are moved thereby 
from the heat sealing assembly 22. The containers 30 are moved onto the 
discharge conveyor 26. As previously mentioned, the screws 14 operate in 
timed relationship with the tacking assembly 16, the indexing feeder 20, 
the heat sealer 22 and the indexing ejector 24 so that a minimal amount of 
time required to close and seal the containers 30 occur as a container 30 
moves through the apparatus 10. 
OPERATION OF THE PREFERRED EMBODIMENT 
The containers 30 have been filled by appropriate filling apparatus and 
discharged onto the feed converyor 28 and, as the containers 30 are moved 
by the conveyor 28, they enter the feed screws 14. The screws 14 move the 
containers 30 under the tacking assembly 16 and under the cover tape 36. 
At this point, downward force is applied by the pads 34 on the tacking 
assembly 16 causes one of the covers 38 to be severed from the tape 36 and 
temporarily located on the container 30. 
Upon leaving the tacking assembly 16 and feed screws 14, the containers 30 
are picked up by the indexing feeder 20 which deposits the containers onto 
the heat sealing assembly 22. The containers 30 are carried thereby to the 
indexing ejector 24. 
During the traverse of the containers 30 between the indexing feeder 20 and 
the indexing ejector 24, the plungers or pistons 48 move downwardly into 
engagement with the covers 38 and with the upper end of the containers 30. 
Heat is applied by the electrical conductors 50 or other suitable means to 
locally heat the cover 38, the adhesive 42 thereon and the upper 
peripheral edge of the containers 30 causing the covers 38 to be securely 
and sealingly attached thereto. From the indexing ejector 24, the 
containers 30 are discharged onto the discharge conveyor so that the 
containers 30 can then be packed into appropriate cartons. 
Thus, it can be appreciated from the foregoing detailed description that 
the closure and sealing apparatus described herein is effective and 
efficient to provide quick and thorough closure and sealing of the 
containers. 
Having described but a single embodiment of the invention, it will be 
understood that many changes and modifications can be made thereto without 
departing from the spirit or scope of the invention and the annexed 
claims.