TECHNICAL FIELD AND BACKGROUND ART.
The present invention relates to a method and an apparatus for automatically
manufacturing glass containers, in particular containers with a narrow mouth or
a mouth having fastening means for lids or closures in general or containers with
wide mouths, such as jugs with or without a spout, vases or containers with or
Techniques are already known for obtaining, from a single gob of glass,
containers which have narrow mouths or are provided with internal or partial threading
or collars for fastening metal closing lids, atomizers, small pumping devices or
other closing elements which require extreme precision of the container neck.
The same techniques are used in order to produce wide-mouth containers
which must have predefined shapes and dimensions which do not require subsequent
machining operations such as cracking-off or fire-polishing of the edge.
Said known techniques essentially consist of processes which are performed
by machines referred to, in technical jargon, as "I.S." (individual section) machines.
There are two types of process which can be performed with said machines:
a first type involves the formation of a parison (preliminary moulded piece from
which the glass article must be formed) by means of pressing of a gob in a blank
A second type of machine involves formation of the parison using blown
compressed air. In both cases the parison is formed with the neck downwards and
is transferred by means of overturning through 180° into the final finishing station
where final moulding of the container is again performed by means of blowing. With
the techniques briefly described above it is not possible to obtain containers
with externally applied elements or decorations, in particular support bases, supporting
stems with feet, with applied elements which surround totally or partially the
base of the container or partially or totally line the container body.
Machines of the carousel type which also perform processing steps
such as those performed in I.S. machines have also been developed, said machines
producing articles with the same characteristics.
In the past, methods for producing articles with decorations applied
as described above have been developed. As can be noted from the following patents:
FR 553 943 A, DE 742457 C, US 1,647,175 A, CH 362,803 A, US 2,269,010 A, the methods
used all refer to manual or semi-automatic production methods.
Moreover from US-A-1 996 910 a method and an apparatus are known for
applying a decoration to glassware. The decoration could be of a colour different
from that of the body of the glassware.
In carrying out the method disclosed, the body of the glass container
may be formed by pressing or blowing. Then the container, set in an inverted position,
is confined in a mould and a receiver is provided for receiving the molten glass
with which the container is to be decorated. A plunger, entering the receiver,
forces or extrudes the molten glass through gates into the mould where the glass
comes into contact with a portion of the container.
After the glass has chilled, the sprue made by the glass in the gates,
is broken and the rough place formed by the breaking away of the sprue is smoothed
off. After the extruding operation has been finished, a body of glass will remain
inside the receiver and this has to be taken out and can be remelted. The mould
and the receiver provide a mould unit which forms the cavity in which the glass
is forced or extruded.
DISCLOSURE OF INVENTION.
The object of the present invention is that of providing containers
with a narrow mouth or wide mouth or one which is in any case precision-made so
as to allow the fastening, if necessary, of means for closing the container itself,
in which the body and/or base of the container are surrounded totally or partially
by applied decorative glass elements of the same or a different colour or in which
feet or decorative inserts are applied onto the external bottom of the base.
These and other objects are fully achieved by the method according
to claim 1 and the apparatus according to claim 2.
The method according to the present invention has the advantage that
the output and the production capacity and the final cost of the product make the
whole system extremely competitive compared to the techniques previously disclosed
in the patents described above.
In particular with respect to known methods as above disclosed in
which the glass is extruded through gates so that it is needed to sever excess
glass or sprue and, as a consequence, it is needed to smooth the base of the container
thus obtained, the present invention provides a method in which the glass is pressed
in the mould so that after the pressing step the container is a finished product.
BRIEF DESCRIPTION OF DRAWINGS.
Characteristic features and advantages will emerge more clearly from
the following description of a preferred sequence of the manufacturing steps illustrated,
purely by way of a non-limiting example, in the accompanying plates of drawings,
BEST MODE FOR CARRYING OUT THE INVENTION.
- Figures 1 to 7 illustrate the sequences for obtaining a container, shown in
Figure 8, in the form of a small bottle with a narrow precision-made neck and with
decoration on the bottom;
- Figures 9, 10, 12, 13, 14 and 15 show containers according to a further embodiment;
- Figure 11 shows, in schematic form, a production line in its entirety which
performs the sequence of process steps.
With reference to the Figures, the method which comprises in combination
a series of steps is now described.
In the first step shown in Figure 1, a gob 1 is inserted, via a funnel
2, into a blank mould 3 which is closed at the bottom by a bottom mould 4 through
which a cylinder or plug 5 passes and penetrates over a short distance inside the
mould 3. The bottom mould 4 is supported by a movable collar 6, as will be illustrated
below. The purpose of the bottom mould 4 is that of pre-forming the neck and the
mouth of the article. AMENDED SHEET
During the second step shown in Figure 2, a buffer-piece 7 is positioned
above the funnel said buffer-piece being provided with channels 7a which allow
the blowing of air which against the plug 5.
During the third step shown in Figure 3, the funnel 2 is removed and
the buffer-piece 7 is positioned against the blank mould in order to seal the cavity
of the blank mould itself. At the same time, the plug 5 is lowered so as to allow
the introduction of air under pressure which pushes the glass against the blank
mould in the top part thereof so as to form a parison 8 which is arranged in an
During the fourth step according to Figure 4, the blank mould is opened
and the parison 8, which remains gripped between the collar 6 and the bottom mould
4, is overturned through 180°, being positioned between the finishing mould 9 formed
by two side shells and a base piece 10.
As soon as the finishing mould has closed, the collar opens, allowing
the parison to assume a stable position inside the finishing mould.
The fifth step according to Figure 5 involves the introduction of
compressed air through a blowing head 11 which is positioned, with a certain degree
of play with respect to the mouth of the container, above the finishing mould.
All these steps belong to the I.S. process and are performed in the machine 35
shown in Fig. 11.
Once the blowing action has terminated, the finishing mould opens,
while an extraction member, arriving above the mould, grips the container 20 which
has been formed, as illustrated in Figure 6, and transfers it from the machine
35 onto a conveyor belt 36 so as to be transported to a pressing and/or injection
machine or station 38 by means of a transferring device 37.
By means of a suitable transferring device 37a and, if necessary,
overturning device, the article is introduced into the station for pressing a gob
19 which surrounds externally the whole of the bottom and partly the body of the
container, as illustrated in Figure 7. During this step, more precisely, the shaped
container is overturned with the mouth directed downwards and resting on a suitable
seat 21 which supports and keeps the container centered with respect to a mould
22 which has an incision consisting of a decoration 18 for example in the form
of petals as shown in Figure 8 which shows the finished product.
For this purpose, the gob 19 is passed through a collar 23 positioned
above the mould 22 and a piston 24 presses the gob into the mould.
The finished product which is obtained is therefore a container which
has a bottom 25 and side walls 26, the bottom being completely or partially surrounded
by a decoration 18. Instead of the external decoration it is possible to provide
decorations inside the bottom and bases as in Figures 12 to 15.
The finished product which is obtained could also have different shapes,
for example it could be small bottle for perfume or cream, as shown in Figures
9 and 10, but it again comprises a bottom 30, side walls 31 and a neck 32 which
is more or less high and provided with a collar 33 or precision fastening means
for a lid or a dispensing pump, not shown.
The finished product also again comprises a base portion 34 which
is made of glass and fixed externally to the bottom of the container body.
The glass portion 34 has a decorative effect and therefore could have
a colour different from that of the container.