Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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The invention relates to a machine for manufac-
turing, filling and sealing packages where the packages are
formed and welded from a flexible web of material with an
expanding-mandrel turntable and with at least one following
filling turntable with a filling station and a welding
station for a head seam.
Such machines are generally used for the manufacture
of liquid containers, e.g. containers for milk, fruit juice
and the like. The web of material, e.g. plastic-coated paper,
is drawn from a feed roll. The individual package blanks are
made from the web by cutting them off and welding them. For
this purpose the blanks are taken up one by one on expanding
mandrels.
In a known machine described in U.S. patent 3,918,236
issued to Allen, November 11, 1975, the packages thus formed,
which remain open only at the top, are alternately transferred
to two filling turntables on which the packages are filled
at a filling station and sealed at a head seam-welding station.
If rectangular packages are produced, there are
two flaps at the top and bottom of each package. To ensure
that these flaps do not get in the way during the subsequent
packing of the filled packages in a packing container, e.g. a
carton, these flaps must either be laid flat against the out-
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side of the package or be cut off. Cutting off the flaps isonly possible if the package sheath at this place has an
additional weld so that no opening is produced by cutting
off the flaps. Such an added welding step is comparatively
expensive. Merely pressing the bottom and top flaps does
not suffice to bring these flaps to a position suitable
for subsequent packing.
The purpose of the invention is therefore to
design a machine of the above type that provides a permanent
adherence of the bottom and top flaps to the outside of the
package. The additional work stations needed for this pur-
pose must be arranged so as to consume as little space as
possible and must be designed in such a way as to be as struc-
turally simple as possible.
This problem is resolved in the invention by
providing forming station for the bottom flaps on the expand-
ing-mandrel turntable, by having a welding die that extends
over the entire length of the head seam at the welding station
for that seam and by having a head-forming turntable that
possesses a forming station for the head flaps and a sealing
station for the head flaps after the filling turntable.
The bottom flaps and the top flaps are preformed
at the respective forming stations in such a way that they
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can be sealed simply to the outside of the package by means
of pressure and heat. Owing to the preforming the forces
arising at the sealing place are kept very small. As a
consequence there is no danger of the sealing joint reopening.
On the other hand the strength requirements of the seal are
small.
The larger number of working stations is produced
in a very simple and space-saving manner by shifting the
stations for forming and sealing the head flaps to a special
head-forming turntable. Compared with the possibility of
providing a larger turntable with more work stations this
solution has the advantage of better use of space. Struc-
turally, the solution is particularly simple, because essen-
tially the same structural parts are used for the head-forming
turntable that are used for the filling turntable.
The invention will be explained more fully with
reference to an embodiment illustrated in the drawing.
In the drawings:
Figure 1 shows a simplified plan view of a machine
for manufacturing, filling and sealing packages;
Figure 2 shows a partial section, enlarged, along
the line II - II in Figure 1, of the forming station for the
bottom flap in its starting position;
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Figure 3 shows, in partial section corresponding
to Figure 2, the forming station in its end position;
Figure 4 shows, in an enlarged partial section
along the line IV - IV in Figure 1, a welding station for
the head seam in the welding position, the initial position
of the welding head being represented in dot-dash lines;
Figure 5 shows, in an enlarged partial section
along the line V - V in Figure 1, a forming station for the
head flaps in the initial position;
Figure 6 shows the station according to Figure
5 in its end position;
Figure 7 shows, in a partial section along the
line VII - VII in Figure 1, a heating station for the head
flaps;
Figure 8 shows, in an enlarged partial section
along the line VIII - VIII in Figure 1, a sealing station
for the head flaps in the initial position, and
Figure 9 shows the station according to Figure 8
in its end position.
The machine shown in Figure 1 is for manufacturing
filling and sealing packages. It has a feed roll 2 mounted
in a machine frame 1, and from this roll a web of material
made, for example, of plastic-coated paper is drawn. First
the web of material 3 passes through scoring station 4 where
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it receives a longitudinal scoring and is then folded over.
In this form web 3 passes through a press 5 in which the
previously printed web is furnished with a datum imprint.
Web 3 then passes through a stamping station 6,
a longitudinal-seam welding station 7, a second pressing
and a feeding station 8 in which the longitudinal seam is
given a second pressing and which also assists in web trans-
port. In a cutting station 10 the blanks are cut off for
the individual packages and in a loading station 11 they
are fitted onto an e~panding mandrel 12 on a turntable 13
that is only indicated by broken lines in the Figure.
Rotating clockwise on turntable 13 the packages
arrive at a folding station 14 at which the two lateral
seams are formed. The fold formed during the folding over
of the web in station 4 lies at the bottom of the package.
In station 14 bottom flaps 16 of package 15, developed
during the fitting of the package onto expanding mandrel
12, are heated and are then sealed at sealing station L 7
(Figure 2 and 3).
Package blank 15, thus prepared for the filling
process and hereinafter referred to simply as the "package",
is transferred in a transfer station 18 from turntable 13
to a filling turntable 19 where it is stripped from the
expanding mandrel. In a filling station 20 package 15 is
filled then in a spreading station 21 the head seam of
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package 15 is drawn apart by spreading fingers. At a
following forming station 22 the head seam is preformed so
that the head seam can be welded at a welding station 23
(Figure 4). The sealed package 15 is then transferred at a
transfer station 24 to a head-forming turntable 25 including
station 26 (Figures 5 and 6) for forming the head flaps,
where the projecting head flaps 27 of package 15 are folded
downwards and thus are preformed. In a following heating
station 28 (Figure 7) the undersides of head flaps 27 and
the outsides of the packages are heated so that in a follow-
ing sealing station 29 (Figures 8 and 9) head flaps 27
can be sealed tightly on the outside of the package.
At an outlet station 30 the finished packages
15 arrive at a discharge tray 31 from which they are taken
for further loading.
Forming station 17 (Figure 2) for the bottom flaps
possesses two laterally movable stamp plates 40, each of
which is joined to guide rolls 41. A hydraulic cylinder
42 bears a vertically movable control body on its piston
rod 43, and on this body side arms 45 are mounted each of
which terminates in a slanted control surface 46 that
engages with guide rolls 41.
At the lower end of each stamp plate 40 a flap-
forming swivel plate 48 is mounted by a hinge 47. Each plate
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48 bears a guide roll 49 which is in contact with curved
guide surfaces 50 on control body 44.
When control body 44 is moved upwards by hydraulic
cylinder 42 stamp plates 40 move laterally towards package
15; simultaneously swivel plates 48 are rotated into the
final position shown in Figure 3.
Figure 2 shows a bottom-flap heater 51 located in
folding station 14 and indicated with dot-dash lines. Heater
51 heats bottom flaps 16 and the lower outside surface of
package 15. When these heated surfaces are pressed against
each other in forming station 17, as represented in Figure
3, flaps 16 are sealed in this position. Stamp plates 40
adjacent the side faces of the package prevent bulging of
the side faces of package 15 when the pressure required for
sealing is applied to the bottom of the package.
At welding station 23 (Figure 4) for the head
seams there is a welding head operated vertically by a
hydraulic cylinder 60. It has a stationary welding die
62 and a swivelling welding die 63 hinged thereto. Both
welding dies, 62 and 63, are heatable. A pressure cylinder
64 engages pivotable welding die 63.
When package 15, whose head seam 65 has already
been preformed at station 22, arrives at head-seam welding
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station 23, welding head 61 is at first in the open position
represented in Figure 4 with dot-dash lines. Hydraulic
cylinder 60 drives welding head 61 downwards. Hydraulic
cylinder 64 then closes the welding head and exerts the
necessary welding pressure and heat on head seam 65. The
lengths of welding dies 62, 63 is so chosen that they extend
over the entire length of head seam 65. Thus the head seam
is completely closed in a single welding process. The head
seam therefore extends into head flaps 27.
Transfer station 24, which is not represented
in detail, is constructed similarly to welding station
23, for the head seams, except that dies 62, 63 are not
heated but cooled. Here head seam 65 is pressed again and
strengthened. The apparatus which holds package 15 at the
head seam in transfer station 24 and whose basic construc-
tion is shown in Figure 4, is arranged to move laterally
and transports package 15 from filling turntable 19 to head-
forming turntable 25.
Head-shaping station 26 (Figures 5 and 6) possesses
a shaping form 71, movable by means of a hydraulic cylinder
70. The plate-shaped centre part of the form 71 bears down-
wardly to against head-flap dies 72. When shaping form 71 is
lowered over package 15 (Figure 6) head-flap dies 72 press
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head flaps 27 downwards so that the latter are preshaped.
At the following head-flap heating station 28
(Figure 7) hot-air blowers 73 engage with their heating
nozzles 74 beneath head flaps 27 and heat the lower side of
the head flaps 27 and the opposite surfaces of the package
side walls. During this step guides 75 hold head flaps 27
in their position.
At the following head-flap sealing sta~ion 29
(Figures 8 and 9) the surfaces thus heated are forced by
laterally pressing flap-sealing dies 80 against the package
side walls where they are firmly sealed. Head flaps 27 are
held in their position before sealing by guide rods 81.
Lateral flap sealing dies 80 are joined at a hinge
82 to each other and to a vertically movable head support
plate 83. A hydraulic cylinder 84 is connected flexibly
through its piston rod 85 and levers 86 with both flap-
sealing dies 80. When piston rod 85 is driven out first
head-support plate 83 is laid against the top of package 15;
then flap-sealing dies 80 press laterally against head flaps
27. During this step the head-support plate 83 prevents the
top of package 15 from bulging upwards from the effect of
the pressure of flap-sealing dies 80.