Note: Descriptions are shown in the official language in which they were submitted.
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The present invention relates to a method and an
arrangement for fastening a stabilizing arrangement on a con-
tainer particularly for fastening a foot onto a bottle. The
invention is suitable for application where both the stabilizing
arrangement and the container consist of plastics material.
There is great interest in the ability to make con-
tainers of plastics material for storing beverages. This inter-
est is due, in part, to the desire to reduce the weight of the
packing used to as great an extent as possible, while simul-
taneously utilizing the good properties of plastics material,particularly ;ts impact strength. The types of plastics
material used for this purpose are, however, relatively
expensiye. Accordingly, it is also necessary for economic
reasons to employ the smallest possible wall thickness of the
containers used, thereby saving on materials.
In order to withstand the loads to which the material
packed in the containers is exposed, the parts of the containers
which are subjected to these stresses, for example, the bottom
of a bottle, must be so constructed as to make the most effec-
tive possible use of the strength of the material. This isparticularly important when containers of plastics material are
used to store materials under pressure, for example, beverages
containing carbon dioxide. Because of the requirements explain-
ed above, this means that the bottom of a container should have
a mainly circular shape.
For a container such as a bottle for storing materials,
it is essential that it should be possible to store the container
in an upright position. With a container having a bottom of
semi-spherical shape, this is impossible. As a result, such
containers are equipped with supporting arrangements, such as
feet. Various types of feet have been used, including parts
projecting from the bottom of the bottle or separate parts fixed
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to the containers, In the last-mentioned case, these parts are
applied to the container by snap engagement, riveting, or
comparable methods.
According to the present invention, a method and an
arrangement are provided for fastening a separate member,
which consists of a supporting arrangement, to a container of
plastics material. According to the invention, the supporting
arrangement is welded to the container. The invention can be
applied to combinations of plastics material when the plastics
material in the supporting arrangement and container are weld-
able. Examples of such plastics materials are polyethylene,
polyethylene terephthalate, acrylonitrile, and polyvinyl chloride.
According to the present invention, the stabilizing
arrangement is guided into a position in which it lies against
the container. The material of the stabilizing arrangement is
thus pressed against the material of the container.
According to one embodiment of the invention, the
inclination of the bottom of the container to become deformed
during the fastening of the arrangement is compensated for by
subjecting the internal volume of the container to pressure.
This embodiment is often suitable for use with thin-walled
containers. As an alternative, the application of pressure is
replaced by a mechanical holding means. A mandrel for trans-
mitting energy, for example, ultrasound, is brought into a
position in which the mandrel transmits energy to the materials
of the stabilizing arrangement and the container in a region
which corresponds substantially to that where the stabilizing
arrangement lies against the container. The stabilizing arrange-
ment is thus welded to the container. When this has been done,
the welded container and stabilizing arrangement are cooled.
After the stabilizing arrangement and the container
have been welded together, a bending moment is produced in the
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stabilizing arrangement and results from displacing the mid-
dle bottom portion of the stabilizing arrangement in relation
to the other parts of the latter before the welding is carried
out. This displacement is achieved by moving the middle
bottom portion in the direction of the bottom of the container
so that after application to the container, an upper edge of
the stabilizing arrangement disposed in this form presses
against the container.
An arrangement according to the invention for fast-
ening stabilizing arrangements on containers consists of a
supporting member which continuously receives the stabilizing
arrangements in unison at a rate at which the stabilizing
arrangements are to be welded to the containers. A gripping
means acts on the containers in such a manner that each in-
dividual container lies against the stabilizing arrangement
under the action of compressive forces when the stabilizing
arrangement lies in the supporting means. A means of giving
up energy, for example, an ultrasonic welding means, is
brought by driving means into contact with the material of the
stabilizing arrangement and transmits energy to the region of
contact between the material of the stabilizing arrangement
and the container. The materials are thereby heated and the
stabilizing arrangement is welded to the container. If
necessary, the container is given a stable shape during
welding utilizing a holding-up means which assumes a position
against the inner surface of the container in the welding
region. Alternatively a pressure application element can be
employed to hold the internal volume of the container under
increased pressure.
Two concentrically disposed rings are provided in the
supporting element for the stabilizing arrangement. The outer
ring preferably has a beaker-like appearance and is adapted
to the outside dimensions of the stabilizing arrangement. In
certain embodiments, the ring is disposed on a number of relative-
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ly soft springs.
The inner ring has an inside diameter which is adapted
to the outside diameter of a mandrel which transmits energy.
In this arrangement, it is possible for the mandrel to slide
through the ring in order to bear against a stabilizing arrange-
ment when the latter rests against the inner ring.
When a stabilizing arrangement has been introduced
into the supporting means, a middle portion of the bottom
thereof rests against the upper surface of the inner ring and
is, at the same time, centered in the supporting means by the
outer ring. In the embodiment where the outer ring is suspended
on springs, it is situated in an upper position under the
action of the springs.
A gripping means acts in sequence on the containers
by bringing them into a position with bottom parts thereof, dis-
posed in the stabilizing arrangement. The latter more or less
embraces the bottom part of the container. The gripping means
then acts on the container in such a manner that it is moved
in the direction of the stabilizing arrangement. The middle
portion of the bottom of the stabilizing arrangement is fixed
in position in the supporting element with respect to the inner
ring, whereas the outer parts of the stabilizing arrangement
are displaced relative to the middle portion of the bottom
through the action of the container. If necessary, this is per-
mitted by the previously mentioned spring suspension of the
outer ring. Through this displacement of the container, reliable
contact is also obtained between the middle portion of the
bottom of the container and the middle portion of the stabiliz-
ing arrangement.
In one embodiment of the invention, an arrangement
simultaneously embraces the mouth p~tion of the container in
such a manner that the latter forms a closed space. Pressure
is applied to the interior of the container, whereby it is
stabilized against mechanical displacement. The element used
for embracing the mouth portion of the container preferably
consists of the previously-mentioned gripping element.
The above-noted assistance in the displacement of the
container for a relative movement of the material of the
stabilizing arrangement is preferably provided by the gripping
element. In one embodiment, the gripping element is displaced
with a roller lying against a cam so that when a relative
displacement occurs between the roller and the cam, the gripping
element is displaced in the direction of the stabilizing arrange-
ment.
With the stabilizing arrangement and the container
fixed in relation to one another in the manner described above,,
a mandrel is thereupon guided through the inner ring, into con-
tact with the material in the middle portion of the bottom of
the stabilizing arrangement so as to transmit ultrasonic energy
thereto. Ultrasonic energy is given up to the material of
the stabilizing arrangement and container, and the stabilizing
` 20 arrangement is thus welded in this region to the bottom of the
container. With the stabilizing arrangement and the container
also fixed in relation to one another by external elements, the
welded part is then cooled, the internal excess pressure (where
applied) is relaxed or the holding-up means used is removed,
whereupon the external fastening element is taken away, and
the container, together with the stabilizing arrangement welded
to it, is carried away from the production unit.
The inner ring is preferably mounted for sliding in
the supporting element, so that the distance of the container
in the axial direction between the upper surface of the inner
ring and the upper surface of the outer ring is adjustable.
The relative displacement between the middle portion
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of the bottom of the stabilizing arrangement in relation to the
remainder of the latter is effected in an alternative embodiment
of the invention through the displacement of the inner ring,
optionally in conjunction with the displacement of the outer
ring.
The positioning of the individual stabilizing arrange-
ment in the supporting element and also the displacement of the
containers with or without the stabilizing arrangements can be
effected in accordance with a known technique. For example,
a suction means may be used to secure the stabilizing arrange-
ment, and a vacuum tube may be employed for bringing the com-
pleted containers to a storage site.
In one aspect of the present invention there is
provided a method of securing a stabilizing arrangement of
plastics material onto a container of plastics material,
said stabilizing arrangement having a bottom middle portion
and a peripherally extending rim portion and said container
also having a bottom middle portion, said method comprising
the steps of: a) placing said container within said stabilizing
arrangement such that there is contact therebetween at their
respective bottom middle portions and while in such position
slidable engagement may occur between said rim portion and
- said container and b) securing said container to said stab-
lizing arrangement at said respective bottom middle portions
only thereby permitting said slidable engagement between
said rim portion and said container to remain possible.
In a further aspect of the present invention there
is provided an arrangement for securing a stabilizing arrange-
ment of plastics material onto a container of plastics
material, the arrangement comprising: a supporting element
for receiving and carrying a stabilizing arrangement to be
secured to the bottom of a container; a gripping element to
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cause a container to lie with a bottom surface thereof
against a stabilizing arrangement in the supporting element
an element for transmitting energy operatively connected to
drive means, the drive means adapted to bring the element
into contact with the material of the stabilizing arrangement
adjoining a region where the material of the stabilizing
arrangement lies against the material of the container, the
element for transmitting energy adapted to transmit energy
to the material of the stabilizing arrangement, and to the
material in the container in the aforesaid region thereby
securing the stabilizing arrangement to the container.
In drawings which illustrate a preferred embodi-
ment of the present invention:-
FIGURE 1 is a perspective view of an arrangement
operating in accordance with the present
invention, and
FIGURE 2 is a partial vertical section illustrat-
ing how the element for welding the
stabilizing arrangement to the container
is mounted.
In Figure 1, a plate 100 is mounted on a shaft
driven by a mechanism 101. The plate is rotatable stepwise
so as to assume fixed stopping positions. A number of
supporting elements 20 are disposed on the plate. The
supporting elements 20 conform to the dimensions of the
stabilizing arrangements 30 which are to be joined to the
container 10. Control elements 21 corresponding to the
dimensions of the containers are connected to the support-
ing elements. An element 50 for transmitting energy,
for example, for ultrasonic welding, is situated at one
of the positions for the supporting elements 20, The
element 50 is equipped with a mandrel 51 which can be
displaced from a lowered position lying under the plate
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100 to an upper position
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77
in which the mandrel is situated in the supporting element 20.
A cooling element 53 is located at a downstream position relative
to the element 50. The cooling element 53 is provided with a
mandrel 52 which can be moved from a position beneath the plate
100 and an operative position situated within the supporting
element 20.
A gripping element 40 associated with each individual
supporting element 20 is arranged to assume a position in
which it secures the individual containers 10 to the supporting
elements 20. In one embodiment of the invention, the gripping
elements are connected to a pressure application means 81, which
consists of a container for compressed air and is equipped
with valves for connecting and disconnecting the gripping element
to and from the pressure application means. The gripping ele-
ments are arranged to make sealing connection with the mouth
portions of the containers, so that when the valve connected to
the pressure application means is opened, an excess pressure is
produced in the containers.
A supporting disc 80 is arranged to cooperate with
the gripping elements 40. In one embodiment, the gripping
elements are provided with a roller 41 lying against the support-
ing plate 80. The direction and shape of the supporting plate
are so selected that when it performs a relative movement with
respect to the supporting disc 80, the gripping element 40 is
moved in the direction of the supporting elements 20.
The stabilizing arrangement is fed with the aid of a
magazine 60 containing individual stabilizing arrangements, a
feed means 61, such as a worm, and a suction element 62. The
suction element 62 secures a stabilizing arrangement fed by the
feed means, and brings it into the desired position in the
supporting elements 20. The suction element 62 is movable
between a position under the plate 100 and a position above the
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supporting means 20. The suction element is common to all the
supporting elements 20. Finished containers with stabilizing
arrangements welded to them can be discharged with the aid of a
suction discharge pipe 70, as shown in the drawing.
Figure 2 shows in detail how the supporting elements
20 are mounted in one emboaiment of the invention. The plate
100 and a mandrel can be seen in the drawing, the mandrel being
either a mandrel 51 for transmitting energy, for example, for
ultrasonic welding, or a mandrel 53 for cooling. In addition,
the bottom part of the container 10 is shown, as well as the
stabilizing arrangement 30. In addition to these parts,
Figure 2 also shows an outer ring 22, preferably of metal, and
an inner ring 23. The outer ring is mounted on a number of
springs 24 so that the ring can be moved between a raised
initial position some distance above the plate 100 and a lowered
position close to the plate. The inner diameter of the outer
ring 20 conforms to the outside diameter of the stabilizing
arrangement 30, so that the outer ring lies against the stabil-
izing arrangements.
The inner ring 23 is joined to the plate 100, and
is usually displaceable with respect to the plate 100, for
example, by being screwed into the plate by means of a screw-
thread. The inside diameter of the ring enables the mandrel
51 or 53 to pass through it. It can also be seen that the plate
100 also permits the passage of the mandrel. The upper surface
of the inner ring lies approximately flush with the bottom
surface of the outer ring 22.
In Figure 2, it can be seen how the middle portion of
the bottom of the container 10 is situated some distance from
the middle portion of the bottom of the stabilizing arrangement
30. This is the starting position for the container when the
latter has first been brought into a position for welding to
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the stabilizing arrangement. In the following stage of the pro-
cess, the container is subjected to forces which are directed
towards the stabilizing arrangement, so that the container to-
gether with the outer parts of the stabilizing arrangement is
displaced towards the plate lO0. The middle portion of the
bottom of the container lO thus reaches a position in which the
material of that portion is pressed against the material in the
' middle portion of the bottom of the stabilizing arrangement.
Since it is suspended on springs 24, the outer ring 22 can follow
the stabilizing arrangement during this movement. The welding
and cooling of the welded region are effected with the container
- and stabilizing arrangement lying in the position close to the
plate lO0.
The mode of operation of an arrangement according to
the description given above is explained below. With the aid
of the feed means 61, the stabilizing arrangements are fed
individually from the magazine 60 to the supporting elements
20. This takes place with the supporting elements 20 in the
position designated position 1. The final positioning of the
stabilizing arrangement in the supporting element is effected
by the suction element 62, which takes over the stabilizing
arrangement 30 after the latter has been delivered by the feed
means 61. The control element 21 assists the suction element
in the correct directing of the stabilizing arrangement.
The plate 100 is thereupon turned one step in its
direction of rotation and a container 10 is placed on the
supporting element 20' by means not shown in the drawing, thus
also being placed on the stabilizing container in the supporting
element. The control element 21' ensures the correct orientation
of the container. The gripper 40' is brought into the position
for closing the mouth portion of the container 10'.
The plate lO0 is rotated one step further. If necessary,
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pressure is then applied to the interior of the container. The
roller 41l' of the gripping element 40" is operated during the
movement of the supporting plate 80 in such a manner that the
container 10" is moved in the direction of the supporting
element 20l'. The stabilizing arrangement 30" is thus acted on
by the container 10" in such a manner that the stabilizing
arrangement and the container assume correct positions relative
to one another for the subsequent welding.
The plate 100 is now rotated one step further. The
mandrel 51 on the element 50 for the supply of energy, for
example, for ultrasonic welding, is moved upwardly towards the
middle portion of the bottom of the stabilizing arrangement 30"'.
Ultrasound energy is transmitted by the mandrel and the material
in the middle portion of the bottom of the stabilizing arrange-
ment, and also the corresponding parts in the bottom of the
container, are heated and the container is thereby welded to
the stabilizing arrangement. The mandrel 51 then returns to its
position below the plate 100.
The plate 100 is now advanced a further step. The
mandrel 53 of the cooling means 52 then assumes a position in
which it lies against the middle portion of the bottom of the
stabilizing arrangement 30 and thus cools the material in this
region and also in the region of the middle portion of the
bottom of the container. This cooling lasts until the necessary
strength has been achieved in the bond between the stabilizing
arrangement and the container.
The plate 100 is advanced one more step, the roller 41
on the gripping element 40 thus being freed from engagement with
the supporting plate 80. The application of pressure to the
interior of the container, in cases where pressure is applied,
then ceases. The gripping element can thus return to its
starting position. The container, together with the stabilizing
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arrangement welded to it, is released for removal from the
production unit. This can be achieved by means of an ejection
device or utilizing a suction pipe 70.
' With the construction described, a number of positions
may be provided for the supporting element 20 between the
position for cooling the welded region and the position for
removal from the production unit. These positions may, for
example, be utilised for inspecting the products and also for
ejecting any which do not pass this inspection.
The arrangement described also makes it possible for
a central control system for the sequence of production
operation to be provided, for example with the aid of a micro-
; dator. The latker attends to all the control functions and
;~ pulses necessary for enabling the operating elements to make
the movements necessary for the sequence of operations.
'~ In some applications, the outer ring 22 may have a
fixed orientation in relation to the plate 100. This arrange-
ment is expedient when the additional security provided through
the movable suspension of the outer ring 22 in respect of the
orientation of the bottom of the container in relation to the
stabilizing arrangement is not necessary.
The foregoing text describes an arrangement working
in accordance with the principle of the invention and consist-
ing of a number of working stations which are positioned on a
plate 100, which performs a circular movement during the course
of the operation. It is obvious that the invention is not
restricted to the use of an apparatus arranged in this manner,
but may also be applied with a more or less linear movement of
production elements. In accordance with the principle of the
invention, it is equally possible for the separate production
stations to be fixed in position and for the containers and
supporting elements to be moved between the various production
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stations. A combination of the two alternative arrangements
may be found economical in certain cases.
An advantage of the invention which has not so far
been mentioned consists in that when fastened to the container,
the stabilizing arrangement is assured of accurate orientation
in relation to the vertical axis of the container. Problems
in connection with the filling of the container are thus over-
come. Previously known foot constructions in which the foot
clips on the container do not provide the accurate orientation
achieved here.
In addition to the above description, the invention
is characterized by the following patent claims.
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