Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
1 FI~LD OF THE INVENTION
The present invention relates to one piece nestable
thin walled containers provided with a unique sidewall and
bottom configuration which allows manufacturers to fill liquid
product at a slightly higher rate where the filling rate was
previously limited by problems of product splashing during
filling operation and causing or leading to contamination of
the sealing area of the container.
BACKGROUN~ OF THE INVENTION
With the increasing costs of dairy products, it has
been found that with individually packaged servings of products,
such as cream, a substantial waste saving can be realized by
reducing the fill quantity. This was f:irst accomplished by
reducing the fill quantity in existing containers; however,
the lower level of product in the contalner was readily apparen-t
and negatively accepted by the consumer. It was subsequently
found that a reduction in the size of the containers created
a product which appeared to be much smaller than previous con-
tainers. To overcome this problem, a new container design was
developed which reduced the overall height of the container,
increased the diameter of the container, and provided a false
bottom in the container. A container of this design appears
to have approximately the same volume as the original containers,
and it was found previous filling problems relating to product
splash were reduced.
The filling rate of individual portion-sized containers
has always been limited and often imposes certain time restraints
on the overall production process. The filling rate of a liquid
product into a small capacity container is limited as splash
0 of the product occurs at higher rates and contaminates the seal-
l ing area. To overcome this problem in stop/start conveyor systems,often two filling stations are provided to reduce the conveyor
dwell time. By providing a container of reduced height, it
was expec-ted that splash problems due to high speed filling
would increase. However, the new container design has unexpect-
antly and surprisingly reduced the problems of splash, and
enabled the manufacturers to increase the filling rate.
SUMMAR~ OF THE INVENTION
The present invention provides a one piece nestable
thin walled container with a unique bottom configuration which
allows the product filling rate to be increased as the problems
of splashed product contaminating the sealing area is not as
frequent. The container comprises a rim portion integrally
at-tached to a tapered sidewall portion extending downwardly and
integrally attached to the bottom portion. The bottom portion
comprises an annular ring portion surrollnding an inwardly extend-
ing curved portion.
In the preferred filling method, liquid ~ets of product
are aimed to strike the sidewall of the container such that
product will 10w down the container wall across the annular
ring portion and over a portion of the curved surface. The con-
tact of the liquid with the container reduces the speed of the
liquid and reduces the tendency of product to splash and possi
bly contaminate the sealing area of the rim during the filling
~5 operation.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention are
shown in the drawings, wherein:
Figure l is a front view of a creamer container of
the new design;
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l Figure 2 is a partial perspective view of a container
cut across its diameter;
Figure 3 is a front view of Figure 2; and
Figure 4 is a cross sectional view of the container
beneath a filling head.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
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The container 2 shown in Figure l has a flat rim por-
tion 6 which is used to heat seal a foil type lid to a filled
container. The sidewalls 3 of the container have been provided
with recessed grooves 4 which extend longitudinally down the side-
wall. These recessed grooves 4 provide additional structural
strength and also help reduce the speed of the product when it
is introduced into the container.
As shown in Figures 2 and 3, the sidewalls of the con-
tainer terminate in an annular ring portion 8 which surrounds andcenters the inwardly directed dome portion 10. This dome por-tion
10 acts as a false bottom and reduces the amount of product neces-
sary to fill the container.
In Figure 4, a creamer container has been located directly
beneath a filling heat 40 which has been provided with a number
of nozzles 42. This would be typical of a container nested in
a conveyor bed and positioned to start the filling operation.
After the filling operation has been complete, the conveyor will
be indexed and the container advanced to the heat seal~ng opera-
tion. In order to complete the heat sealing operation, the flange6 of the container must be free of all product and any drips or
splash of product on the flange area 6 will result in improper
heat sealing of the lid to the container and subse~uent spoilage
of the product. The nozzles 42 have been provided with a further
restriction 44, which is of reduced diameter and prevents dripping
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1 of the product after the filling operation is complete. There-
fore -the restrictions 44 act as a valve where the surface tension
of the product at the end of restriction 44 is sufficient to
prevent dripping~ Although this restriction 44 provides a very
simple method of controlling flow of the product, it creates
problems during the filling operation. The reduced diameter
of the restriction 44 causes a very narrow jet of product to be
introduced into the container. The velocity of the jet or pro-
duct is a function of this diameter, and in order to reduce the
velocity, the filling head 40 has been provided with a number of
nozzles. However, the velocity of the product leaving-each nozzle
is still quite high. In the preferred filling method, the nozzles
have been placed about the circumference of the filling head and
at an angle such that the jet of the product strikes the container
sidewall at an oblique compound angle. This compound angle
introcluces a slight swirling effect of t:he product and also
ensures that the jet of product flows across a number of recessed
grooves 4. The product tends to coat and flow down the sidewall
to the annular ring 8 at which point it flows across this surface
and subsequently coats a portion of the dome surface lO. It can
be appreciated that the narrow jet of product has now dispersed
considerably and widened due to the frictional losses and drag
created when the product flows over these surfaces. As this
initial product flows up and across the dome surface 10, the
surface tension between the product and the container combined
with the gravitational force exerted on the product, tend to
keep the product in contact with the dome. However, the upward
momentum of the product tends to counteract these forces. The
filling rate is adjusted such that the point at which the product
leaves the dome surface, the interaction of the product with the
4 ~
1 surface of the sidewall, -the annular rinq and the dome portion,
has reduced the speed of the product such that the momentum of
the product is not of sufficient magnitude to cause the product
to leave the cavity of the container. Also it must be remembered
that there is a number of nozzles introducing the product into
the container, therefore when the product separates from the
dome, there may well be a collision of product roughly directly
above the center of the dome 10. This collision tends to further
reduce the momentum of the product and reduces the possibility
of the product leaving the container cavity.
Product that lands on the rim 6 will cause an ineffect-
ive heat seal. However, it should also be noted that if the
filling head 40 is splashed with product, there is a good possi-
bility that this product will drip on the heat sealing area 6.
Therefore it is important to assure no product splashes on the
rim 6 directly and it is also important tha-t the product does
not contact the filling head ~0.
This inver,tion has been found useful with cream contalners
where the ratio of overall height to base diameter of the container
is approximately 1:1 and particularly useful in containers with
a height and base diameter of approximately 1 inch. It has also
been found in such containers that -the ratio of the width of the
annular ring to the horizontal radius of the dome at the bottom
of the container oE approximately 1:2 functions quite satisfactor-
ily. The filling rate will have bo be considered when designingcontainers according to this invention~ and these ratios may
have to change if an extremely fast filling rate is used. It is
apparent that problems of splash decrease as the height of the
container increases~ and therefore faster filling s~eeds are
possible with larger containers.
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1 As can be seen in Figure 4, the accumulation of liquid
45, at either side of the dome 10, is initially quite rapid
and this accumulation of liquid further reduces the tendency
of the product being introduced in the container to splash.
It is believed the accumulation of liquid 45 helps to dissipate
some of the energy of the jets of product flowing down the
sidewalls of the container and the dome 10 provi.des a smooth
surface over which the accumulated product may ar.ise.
Although it is difficult to quantify the filling rates
as these are a function of at least the size of the container,
the product, and the method of filling, it has been found that
the maximum filling rate with a container of this design is
greater than the maximum filling rate with prior art flat
bottom containers of approximately equa:L size.
To this point, the container has been described in
regards to the preferred method o~ peripherally filling of the
container; however, it should also be noted that the design
functions satisfactorily when product is ~irst directed at
the dome surface and dispersed to the sides of the container.
As in peripheral filling, the interaction of the various compo-
nents of the container reduce the velocity of the product such :
that the momentum of the product is not of sufficient magnitude
to allow it to leave the confines of the container.
The unique container design has reduced the problem
of product splash during the filling operation and may alsopermit the filling rate to be increased.
Although various preferred embodiments of the invention
have been described herein in detail, it will be appreciated
by one s~illed in -the art that variations may be made thereto
without departing from the spirit of the invention or the scope
of the appended claims.
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