U.S. patent application number 10/457929 was filed with the patent office on 2003-11-13 for installation for packaging liquid doses in sealed bags and use thereof.
Invention is credited to Susini, Etienne.
Application Number | 20030208993 10/457929 |
Document ID | / |
Family ID | 8175072 |
Filed Date | 2003-11-13 |
United States Patent
Application |
20030208993 |
Kind Code |
A1 |
Susini, Etienne |
November 13, 2003 |
Installation for packaging liquid doses in sealed bags and use
thereof
Abstract
The invention concerns an installation for packaging liquid
doses in sealed bags produced from a longitudinally open blown
tubing, comprising a vertical frame, means for moving along said
blown tubing, a pipe supplying said liquid, means for welding said
opening, means for welding the opposite edges of said tubing
beneath the end of said pipe and cutting means. A first welding and
cutting station is arranged on either side of said pipe, to provide
first weld seams and cuts, a second welding and cutting station is
arranged beneath the end of said pipe to provide first weld seams
and cuts, a second welding and cutting station is arranged beneath
the end of said pipe to produce transverse weld seams to link the
two adjacent ends of the first weld seams located on either side of
said feeding pipe of two adjacent pairs of said first weld seams
and to form cut-outs.
Inventors: |
Susini, Etienne;
(Villescresnes, FR) |
Correspondence
Address: |
STURM & FIX LLP
206 SIXTH AVENUE
SUITE 1213
DES MOINES
IA
50309-4076
US
|
Family ID: |
8175072 |
Appl. No.: |
10/457929 |
Filed: |
June 10, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10457929 |
Jun 10, 2003 |
|
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PCT/IB01/02296 |
Dec 4, 2001 |
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Current U.S.
Class: |
53/551 ;
53/133.1; 53/284.7 |
Current CPC
Class: |
B65B 9/213 20130101;
B65B 61/205 20130101; B65B 51/303 20130101 |
Class at
Publication: |
53/551 ;
53/133.1; 53/284.7 |
International
Class: |
B65B 009/20; B65B
061/20 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 12, 2000 |
EP |
00811178.3 |
Claims
1. An installation for packaging doses of liquid in sealed bags
produced from a sheath (G) of a heat-sealable flexible material,
open longitudinally, comprising a vertical framework (B) comprising
means (50, 51, 74-77) for causing this sheath (G) to pass downward,
a feed pipe (41) for said liquid entering said sheath (G) through
said longitudinal opening, means (38, 39) for welding said
longitudinal opening below the passage for said feed pipe (41)
through said longitudinal opening, transverse welding means (68)
for connecting the opposite longitudinal edges of said sheath (G)
under the dispensing end of said feed pipe (41), and cutting means
(42, 43, 72, 73) for separating the bags containing said doses from
said sheath, characterized in that this installation comprises a
first welding and cutting station (3), arranged on each side of
said feed pipe (41) to form first welds and cuts on the outside of
these first welds, a second welding and cutting station (4) below
the end of said feed pipe (41) for forming transverse welds for
connecting the two adjacent ends of the first welds situated on
each side of said feed pipe of two adjacent pairs of said first
welds and to form cuts on the outside of said transverse welds.
2. The installation as claimed in claim 1, characterized in that
said first and second welding and cutting stations (3, 4) each
comprise at least two supports (11, 12; 59-62) arranged on each
side of said sheath (G), means (13, 14; 47a, 47b) of guiding these
supports (11, 12; 59-62) in a direction transverse to the movement
of said sheath (G), actuating means (15, 16; 53, 54) for moving
said supports (11, 12; 5962) along their respective guide means, in
opposite directions to one another, to move them closer together or
further apart, welding means (38, 39, 68, 69), cutting means (42,
43, 72, 73) and fixing means (21-24, 36, 100, 101) for connecting
said welding (38, 39, 68, 69) and cutting (42, 43, 72, 73) means
removably to said respective supports (11, 12; 59-62).
3. The installation as claimed in one of the preceding claims,
characterized in that the supports (59, 60) of the cutting and
welding means (69, 73) of said second welding and cutting station
(4) situated on one side of said sheath (G) and the supports (61,
62) of the cutting and welding means (68, 72) of this same welding
and cutting station (4) situated on the other side of said sheath
(G) are each secured to an independent actuating member (63-66) for
moving the supports (59, 60) arranged on one side of said sheath
(G) and those (61, 62) arranged on the other side of this sheath
(G) against each other and for parting them, and in that two
sliding devices (57, 58) can be moved in two horizontal and
mutually parallel paths, each of them being dynamically connected
to two of said supports (59, 60, 61, 62) situated on the same side
of said sheath (G), and are engaged with drive means (M1-M4) for
causing them to slide along said paths, in two opposite directions
alternately, so as to alternately place said welding and cutting
means respectively, in a determined working position with respect
to said sheath (G).
4. The installation as claimed in claim 3, characterized in that
each of the two sliding devices (57, 58) dynamically connected to
said respective supports (59-62) arranged on each side of said
sheath (G), are secured to two respective sliding members (55, 56)
mounted on guide means (47a, 47b) defining a horizontal path
perpendicular to the paths of said sliding devices (57, 58), said
sliding members each being engaged with drive means (53, 54) for
alternately bringing them closer together or moving them further
apart, means (74-77) for gripping said sheath (G) being secured to
said sliding members (55, 56), the means (47a, 47b) for guiding
these sliding members (55, 56) being secured to a chassis (47)
engaged with vertical guidance and drive means (50, 51) to drive
said chassis alternately downward and upward, the length of this
travel being determined according to the vertical dimension of said
sealed bags.
5. The installation as claimed in claim 3, characterized in that
the vertical position of the welding (38, 39) and cutting (42, 43)
means of said first welding and cutting station is fixed during the
packaging process, these welding (38, 39) and cutting (42, 43)
means being vertically aligned on each side of said sheath (G) with
a spacing corresponding to the spacing between two successive ones
of said sealed bags.
6. The installation as claimed in claim 5, characterized in that
said welding (38, 39) and cutting (42, 43) means are secured to a
common support (5) connected to said framework (B2) by
height-adjustment means (7, 70, 71, VR) and means (10) of locking
these adjusting means.
7. The installation as claimed in one of the preceding claims,
characterized in that said welding means (38, 39, 68) consist of
pulsed electrical heating means.
8. The installation as claimed in one of the preceding claims,
characterized in that said welding means (68) comprise a mating
support (69) associated with cooling means.
9. An installation for packaging doses of liquid in sealed bags
comprising a valve (V) formed by a passage formed between two
thermoplastic films arranged inside said sheath at the location of
each of said bags, running transversely to said sheath, and a pouch
the end wall of which is adjacent to the entry to said passage of
the valve (V) as claimed in one of the preceding claims,
characterized in that it comprises, upstream of said first welding
and cutting station (3), a station (2) for introducing one end of a
straw (P) into said passage in the valve (V), this station (2)
comprising means (84) for piercing the end wall of said pouch
adjacent to the entry to said passage in the valve (V) and means
(82) for inserting one end of a straw (P) into the entry of said
passage in the valve (V) and the remainder of said straw (P) into
said pouch.
10. The installation as claimed in claim 9, characterized in that
said station (2) for introducing a straw (P) into said passage in
the valve (V) comprises means (87-93) for flattening and clamping
said sheath (G) on each side of said passage in the valve (V), a
transfer disk (78) mounted to pivot and roughly coplanar with said
flattened sheath (G), a multitude of radial housings (82b) for said
straws (P), distributed at uniform angles over this transfer disk
(78), an equivalent series of radial guide means (82) for said
means (84) for piercing the end walls of said pouches, alternating
with said housings (82b), means (80, 81) for moving said transfer
disk (78) step by step in order in succession to bring a piercing
member (84) and one of said radial housings (82b) into alignment
with each of said passages in valves (V), and means (96) for moving
said piercing member (84) and said straw (P) radially and
alternately toward the outside of the transfer disk (78) when these
items are respectively aligned with said passage in the valve
(V).
11. The use of the installation as claimed in one of the preceding
claims for the packaging, by continuous filling, of said sheath (G)
with said liquid at the same time as performing the steps of
welding and cutting the periphery of said bags.
Description
[0001] The present invention relates to an installation for
packaging doses of liquid in sealed bags produced from a sheath of
a heat-sealable flexible material, open longitudinally, comprising
a vertical framework comprising means for causing this sheath to
pass downward, a feed pipe for said liquid entering said sheath
through said longitudinal opening, means for welding said
longitudinal opening below the passage for said filling pipe
through said longitudinal opening, transverse welding means for
connecting the opposite longitudinal edges of said sheath under the
dispensing end of said feed pipe, and cutting means for separating
the bags containing said doses, and to the use of this
installation.
[0002] A bag of this type, also comprising a valve adjacent to a
pouch containing a straw one end of which is engaged in the entry
to the valve, its method of manufacture and of packaging are
described in EP-0 948 446. As far as the actual packaging is
concerned, this document does, however, provide relatively little
detail and does not disclose the means used for this purpose. Nor
does it disclose any solution for continuous packaging. As
described, the shape of the bags is given by the edges of the
material in web form and by transverse welds, connecting the two
longitudinal edges of the web-form material, giving the bag a
quadrilateral profile.
[0003] The method that consists in continuous vertical packaging of
bags, single-serving cartons or parallelepipedal bricks from a
continuous tubular material, is well known. However, vertical
packaging installations used for this purpose permit the production
only of volumes of quadrangular profiles or volumes with regulated
surfaces, dictated by the tubular shape of the sheath from which
they are made, leaving little or no place for the imagination and
not allowing the bags thus produced to be given a novel or even
playful nature. In addition, a given installation can produce only
bags of identical shapes and sizes. Only the decoration and/or the
captions borne on the external surface of the bag allow the bag to
be customized to the product it contains and/or the brand name of
the manufacturer of the product packaged in this bag.
[0004] The main object of the present invention is to allow the
continuous packaging of liquid, advantageously, although not
exclusively, into bag blanks as described in the aforementioned
document, and the formation of bags capable of exhibiting various
shapes easily modified to suit the requirements or shape that is to
be given to the bag with a minimum amount of work.
[0005] To this end, the subject of the present invention is first
of all an installation for packaging doses of liquid in sealed bags
produced from a sheath of a heat-sealable flexible material, as
claimed in claim 1. Another subject of this invention is then the
use of this installation as claimed in claim 10.
[0006] One of the advantages of this installation is that the bag
is given most of the shape of its periphery before it is filled,
leaving between the two welded parts on each side of the filling
pipe only a passage for this pipe, so that the liquid is
practically already confined within the periphery of the bag. This
welding that gives most of the shape to the bag is accompanied by
the cutting operation for separating the welded portions from the
sheath from which the bag is formed. By virtue of this design, it
becomes possible to vary the shape of the periphery given to the
bag, because this is no longer dictated by the straight edges of
the tubular sheath.
[0007] In consequence, all that is required is a change of welding
and cutting tools and the profile given to the bag can be changed.
Combining a given profile with appropriate printing of the profile
makes it possible to give the bag particular appearances. Thus, for
example, the profile may be reminiscent of that of a fruit, the
printing on the bag then reproducing that of the skin of the fruit.
Such a bag can then be used to package the juice of the fruit in
whose likeness the bag is produced. This appearance is obviously
not restricted to the aforementioned example; it may adopt that of
imaginary or real people, caricatures, objects connected with
sports events, animals, etc. The profile given to the bag may also
be chosen to evoke a topic used in the context of an advertising
campaign.
[0008] Advantageously, when the packaging installation is used to
fill bags the blanks of which are produced in accordance with EP-0
948 446 as mentioned above, the workstations of the installation
relating to the packaging of the actual liquid are preceded by a
station intended to open the end wall of a pouch adjacent to the
passage in the valve and to place a straw in this passage and in
the adjacent pouch.
[0009] Other features and advantages of the present invention will
become apparent from reading the description which follows, given
in relation to the attached drawings which, schematically and by
way of example, depict one particular embodiment of the
installation that is the subject of the present invention and its
use.
[0010] FIG. 1 is an elevation of this embodiment;
[0011] FIG. 2 is an enlarged part view of FIG. 1, illustrating the
first welding and cutting station;
[0012] FIG. 3 is a view on III-III of FIG. 2, with the welding and
cutting tool removed;
[0013] FIG. 4 is a part view of the welding and cutting tool alone,
viewed on IV-IV of FIG. 2;
[0014] FIG. 5 is a view on V-V of the FIG. 1, illustrating the
second welding and cutting station;
[0015] FIG. 6 is a perspective view of the welding and cutting
tools alone, that are intended to be associated with the second
welding and cutting station of FIG. 5;
[0016] FIG. 7 is an enlarged part view of FIG. 1;
[0017] FIG. 8 is a section on VIII-VIII of FIG. 7;
[0018] FIG. 9 is an enlarged part view of a detail of FIG. 8;
[0019] FIG. 10 is a diagram of the series of operations of the
second welding and cutting station.
[0020] The installation illustrated in FIG. 1 comprises a framework
B comprising two parts B1 and B2 side by side. The part B1 is
intended to form straws P and feed them into bags the blanks of
which, in this example, are already formed from a web-form material
in the form of a flattened sheath G. This sheath G is stored in the
form of a reel (not depicted) and conveyed to the part B2 of the
framework B by a roller 1, arranged at the top of this part B2
which more especially forms the subject of the present
invention.
[0021] This sheath G is longitudinally open along its left-hand
edge with reference to FIG. 1. In this example, as it travels down,
this sheath G passes through a straw-loading station 2. This
station is obviously needed only if straws P have to be loaded into
the bags formed in the sheath G and more particularly when these
bags are fitted with valves. The sheath G then passes through a
first welding and cutting station 3 and through a second welding
and cutting station 4.
[0022] The first welding and cutting station 3 is depicted in
greater detail in FIGS. 2 to 4 and comprises a support frame 5
connected to the framework B2 by two runners 6 mounted on two
vertical slides 7 secured at each of their ends to two parallel
fixing plates 8 fixed to the framework B2 by bolts 9. Wing nuts 10
are used to fix the runners 6 onto the vertical slides 7. An
adjusting handwheel VR is secured to a shaft 70 the end of which is
engaged with a screw jack 71 intended to move the support frame 5
vertically on the vertical slides 7. This adjustment is intended to
alter the position of the welding and cutting station to suit the
size of the bags in which the liquid is packaged.
[0023] Two tool supports 11 and 12 are each mounted to slide on one
of two slides 13 and 14 respectively, that are fixed to two
parallel sides of the support frame 5. Each of these supports 11,
12 is connected to an actuator 15 and 16 respectively, to cause
these supports to slide on the slides 13, 14. Each tool support 11,
12 comprises two tool holders 17, 18 and 19, 20, respectively. Each
tool holder 17-20 has a fixing dowel 21, 22, 23, or 24,
respectively, each of which dowels passes through supports 25, 26,
27 and 28 respectively, exhibiting the form of pairs of parallel
plates, pierced with coaxial openings. At one of their ends, the
fixing dowels 21-24 end in heads 21a, 22a, 23a and 24a,
respectively, while keys 21b, 22b, 23b and 24b respectively, retain
them at their other ends.
[0024] The two tool holders 17, 18 and 19, 20, respectively, of the
tool supports 11, 12 are each mounted to slide on two respective
slides 29a, 29b and 30a, 30b. Wing nuts 17a, 18a, 17b, 18b, 19a and
20a, respectively, two other nuts symmetric with the last two 19a,
20a not being visible, are used to clamp the tool holders 17-20 on
the slides 29a, 29b, 30a, 30b. Two adjusting knobs 31, 32 (FIG. 2)
are secured to spindles of which a threaded part is engaged with a
nut (not depicted) secured to each of the supports 17, 18
respectively. These adjusting knobs 31, 32 are used to move the
supports relative to the slides 29a, 29b.
[0025] FIGS. 2 and 4 show in greater detail three of the four
tools, the fourth not being visible, 33, 34 and 35 mounted on the
four tool holders 17-20. Each tool 33-35 comprises on its rear face
a fixing block, of which just two, 36, 37, are visible in FIG. 4.
Each block has, passing through it, a bore 36a, 37a intended for
the passage of a fixing dowel 21, 23, respectively, the other two
bores not being visible.
[0026] Each tool 33, 34 comprises, in its upper part, a welding
electrode 38, 39 that can be seen in broken line in FIG. 2. The
flat surfaces of the tool 35 and of the non-visible tool facing the
tool 34, are situated opposite electrodes 38, 39, respectively, and
constitute opposite electrodes. The welds made by the two
electrodes 38, 39 define the entire periphery of the bag except for
a vertical passage 40 (FIG. 2) formed between the tools 33, 34 on
the one hand, and between the tool 35 and the non-visible tool
situated facing the tool 34 (FIG. 2). The vertical passage 40 is
intended to allow a liquid feed pipe 41 to pass (FIG. 1).
[0027] The lower parts of the two tools 33, 34 (FIGS. 2 and 4) each
comprise a moving cutter 42, 43 actuated by an actuator 44, 45.
These moving cutters 42, 43 have a shape corresponding to the
external edge of the welding electrodes 38, 39. The two tools, of
which just the tool 35 is visible, comprise, facing each moving
cutter 42, 43, a receiving groove of which only the groove 46 is
visible in FIG. 4, of a shape corresponding to that of the moving
cutter 42.
[0028] The actuating mechanism of the second welding and cutting
station 4 is illustrated in greater detail by FIG. 5, while the
tools intended to be associated with this actuating mechanism are
illustrated in FIG. 6. The entirety of this actuating mechanism is
carried by a horizontal rectangular chassis 47 secured to two
vertical slides 48, 49, each engaged with a linear motor 50, 51,
each of which is fixed to the framework B2 (FIG. 1) by fixing
brackets 52.
[0029] The two short sides of the rectangular chassis 47 each bear
an actuator 53, 54, each of these being in engagement with a slide
55 and 56 respectively, mounted on the chassis via guide rails (not
depicted) running along the two sides 47a, 47b of the chassis 47.
The slide 55 bears a runner 57 able to be moved at right angles to
the slide 55 by drive motors M1, M2, that is to say transversely to
the chassis 47. The slide 56 also bears a runner 58 that can also
be moved transversely to the chassis, by drive motors M3, M4.
[0030] Each runner 57, 58 carries two tool holders 59, 60 and 61,
62, respectively, each of these being secured to an actuator 63, 64
and 65, 66, respectively. A free roller 67, arranged transversely
at the center of the chassis 47 is intended to take the bottom of
the sheath G.
[0031] The tools intended to be mounted on the second welding and
cutting station 4 are illustrated in perspective in FIG. 6. These
tools comprise a welding electrode 68 situated facing an opposite
electrode 69, these two members 68, 69 being fixed to the supports
60, 62 by fixing pieces 100. Advantageously, the opposite electrode
69 is associated with cooling means. The two other supports 59, 61
bear the cutting members 72, 73. Whilst the member 73 is a fixed
cutting anvil member connected to the support 59 by fixing pieces
100, the cutting member 72 is formed of a block mounted to slide on
fixing rods 101 and pressed toward the cutting anvil member 73 by
return springs 102. This set-up allows the block to retreat when it
meets the cutting anvil member 73 and thus to allow the cutters
(not visible) to deploy.
[0032] The welding members 68, 69 and cutting members 72, 73 are
shaped to simultaneously close then cut lower and upper parts of
two adjacent bags, in order to connect, through the space 40 left
free, the welds made at the first welding and cutting station 3 by
the electrodes 38 and 39, thus forming a continuous weld delimiting
a packaging volume for the liquid.
[0033] Two pairs of gripping lips 74, 75; 76, 77 are arranged
respectively above and below these welding 68, 69 and cutting 72,
73 tools and are intended to be fixed to the slides 55 and 56
respectively. The lips 74 and 76 advantageously exhibit an attached
tongue 74a, 76a, made of an elastically compressible material such
as an elastomeric material used for producing seals. These lips
serve to grip the sheath G during the welding and cutting
operations. Given that, as will be explained in the course of the
description relating to the operation, the workstation is moved
downward by the linear motors 50, 51 during the welding and cutting
operations, the gripping lips 74-77 also serve to pull the sheath G
without slippage during these welding and cutting operations.
[0034] According to a preferred embodiment of the present
invention, the bags formed by the welding and cutting units 3, 4
comprise a valve, for example, like the bag described in EP-0 948
446.
[0035] The packaging installation according to the present
invention comprises, upstream of the welding and cutting stations
3, 4, a station 2 for loading the straws P into the passages formed
by the valves formed in the sheath G. This station will now be
described with reference in particular to FIGS. 7 and 8.
[0036] A transfer disk 78 is mounted to pivot about a horizontal
spindle perpendicular to the plane of the sheath G. For this, the
center 78a of the disk 78 is fixed and the disk 78 is fixed to a
drive means 78b mounted to pivot using ball bearings 79. A
gearwheel 78c secured to the hub 78b is connected to a gearwheel
80a of a drive motor 80 by a toothed belt 81. The surface of the
disk bears twelve radial slides 82, mounted to slide in supports
82a. Each radial slide 82 is pushed toward the center of the
transfer disk 78 by return springs 83 and each of them bears a
pusher 84. Radial housings 82b are mounted in the radial slides 82,
to accommodate the straws P.
[0037] One radial slide 82 in two carries a folded straw P in an
insertion position. Advantageously, these straws are already shaped
as described in WO 99/3791. The pushers 84 of the other radial
slides 82 situated between those that bear the straws P are
configured as puncturing members. What actually happens is that the
valves V described in EP 0 948 446 mentioned above occupy the
right-hand part of the sheath G (FIG. 7) and their entry is closed
by a diaphragm that the pushers 84 configured as puncturing members
are intended to perforate in order to give access to the passage in
the valve V.
[0038] FIG. 9 shows the device for guiding and clamping the various
layers of films that form the sheath in which the valves V are
formed. In fact, there are two guiding and clamping devices 85, 86,
one situated above and the other below the line of perforation and
insertion of straws P, which line consists of a horizontal line
passing through the center of the transfer disk 78.
[0039] Each guiding and clamping device 85, 86 has two fixed
support surfaces 87, 88 arranged in the shape of a V and between
which the edge of the transfer disk 78 passes together with the
ends of the slides 82, 82a. These support surfaces 87, 88 are fixed
to a part of the framework B2. Clamping surfaces 89, 90, 91 are
secured, one of them, 89, to an actuator 92, and the others, 90, 91
to an actuator 93. Two other actuators associated with similar
clamping surfaces, and of which only the actuator 93a is visible in
FIG. 7, operate in an identical way and serve the same goal as the
actuators 92, 93. They are arranged symmetrically above the valve V
and thus allow the layers of film of the sheath G to be clamped
above this valve V. A film intended to form the outer wall of the
bags and a film intended to form the diaphragm sealing a pouch for
containing the bent part of the straw P are arranged between the
support surface 87 and the clamping surface 89. The film forming
the other wall of the bag and a first film for forming the valve V
are clamped between the two clamping surfaces 90, 91, while the
second film of the valve is clamped between the clamping surface 91
and the bearing surface 88. Ball and spring spacer devices 94, 95
are intended to separate the two clamping surfaces 90, 91 when the
actuator 93 is in the open position.
[0040] The fixed center 78a of the transfer disk 78 bears an
actuator 96 aligned with the horizontal line of perforation and
insertion of straws P passing through the center of this transfer
disk 78 and through the passage in the valve V, aligned with the
diameter of this transfer disk 78.
[0041] A feed station 97 feeding the transfer disk 78 with straws P
lies diametrically opposite the loading station 2 where straws P
are loaded into the passages in the valves V. This station
comprises fiber-optic positioning means 98 for ensuring precise
angular alignment of the transfer disk 78. A pusher 99 is mounted
to slide along an axis passing through the center of the transfer
disk 78. The front part of this pusher 99 has a smaller diameter
than the rear part, so as to be able to enter the bore of the straw
P to keep the straw aligned by pushing it into a housing 82b
secured to the transfer disk 78.
[0042] The way in which the packaging installation works will now
be explained with reference to FIGS. 10 and 11 which give the
timing sequence for the operations relating to the first and second
welding and cutting stations 4. Given that the operations relating
to the straw loading station 2 are performed on the sheath G while
it is stationary, as are those at the first welding and cutting
station, whereas the second welding and cutting station 4 is also
used to advance the sheath step by step and therefore makes a
reciprocating vertical movement at the same time as the welding and
cutting operations, the operations of the straw loading station 2
and of the first welding and cutting station 3 are performed
between the operations of the second welding and cutting station
4.
[0043] It must first of all be emphasized that the liquid feed pipe
41 extends down as far as a level mid-way up the height of the
cutting tools 42, 43 (FIGS. 1, 2 and 4), that is to say a level
situated appreciably below the first welding station, thus allowing
liquid to be fed in at a continuous and constant flow rate without
the liquid overflowing.
[0044] While the sheath G is stationary, the straw loading station
2 first of all performs the operation of puncturing the film that
seals the entry to the valve V. For this, the actuators 92, 93
clamp the bearing and clamping surfaces 87-91 against each other,
immobilizing the sheath G. The actuator 96 placed at the center of
the transfer disk 78 is actuated and pushes the slide 82 secured to
a perforator 84 toward the sheath G to make through the latter an
opening allowing access to the passage of the valve V. The actuator
96 retreats and the slide 82 is moved back by the return springs
83.
[0045] Next, the motor 80 causes the transfer disk 78 to rotate
through 30.degree., corresponding to one angular spacing separating
two adjacent slides 82, in order to position a slide 82 into which
a straw P has been loaded. The actuator 96 is then actuated once
again to engage the front end of the straw P in the passage in the
valve V. The depth to which the straw P is engaged in the valve V
is chosen so that the valve remains closed. The actuator 96 returns
to its initial position and the springs 83 return the slide 82
back, while the straw P remains engaged in the passage in the valve
V.
[0046] The operations of puncturing and of loading the straw P
which have just been described are performed at the same time as
the welding and cutting operations at the first welding and cutting
station 3. The sequence of events is illustrated in FIG. 10. The
actuators 15 and 16 press the tools 33, 34 and the tools facing
them and of which just the tool 35 is visible in FIGS. 2 and 4,
against each other. The welding electrodes 38, 39 are then powered
with pulses of current to perform the welding of the sheath G.
Next, the actuator 44 is actuated to cause the cutters 42, 43 to
enter the receiving grooves facing them and of which just the
groove 46 is visible in FIG. 4, thus cutting the sheath G on the
outside of the welds formed by the electrodes 38, 39, and thus
separating them from the remainder of the sheath G.
[0047] As can be seen in FIG. 1, the welding electrodes 38, 39 and
the cutters 42, 43 lie at two different levels, which means that
the welding and cutting operations performed almost simultaneously
by the welding and cutting station are performed on two different
bags following on from one another along the sheath G. In this way,
one bag is welded while the one just below it is being filled with
liquid and at the same time cut. During the next operation cycle,
the bag that was welded is lowered by one spacing and therefore
finds itself facing the cutters 42, 43.
[0048] The sequence of events in the welding and cutting operations
at the second welding and cutting station 4 is illustrated in FIG.
11, referring more especially to FIGS. 5 and 6. First of all, after
the end of the operations performed at the first welding and
cutting station 3, the actuators 53, 54 drive the tools 72-77
against each other, so that the sheath G is trapped between the
lips 74, 75 on the one hand and between the lips 76, 77 on the
other, these two lines of gripping lying respectively one above and
one below the welding 68, 69 and cutting 73, 74 tools. During the
operations that will follow, all of the members mounted on the
chassis 47 will be driven downward by the linear motors 50, 51.
[0049] The length of the downward travel will correspond precisely
to the length separating two successive bags or to the length
separating two successive valves V, which amounts to the same
thing. However, whereas the valves V are formed on the sheath G at
regular and precise spacings before the operation of packaging
liquid into the bags, the bags are not formed until during the
packaging operation, at the same time as this, which means that it
is the valves V which serve as marker means.
[0050] Next, the actuators 64, 66 controlling the welding tools 68,
69 corresponding to the electrode and to the opposite welding
electrode press these tools against each other. The electrodes are
powered with current in pulses, making it possible to limit the
welding time, then to immediately cool afterwards in an extremely
short space of time, it being possible for the opposite electrode
69 to serve as a cooling member by being connected to means (not
depicted) for example a bimetal with Peltier effect, to quickly
lower its temperature, while at the same time keeping the welded
parts clamped together, something that cannot be achieved with
resistive heating. The cooling following the welding keeping the
parts clamped together is important in this case. This is because
at the time of this welding, the bag is full of liquid and has
therefore been deformed, which means that the welded surface would
crumple. By keeping it clamped as it cools, the appearance of this
welded portion is markedly improved.
[0051] Next, the actuators 64, 66 are opened and it is the turn of
the runners 57, 58 to be moved by the drive motors M1, M2, M3, M4
in order to bring the cutting tools 72, 73 into the place of the
welding tools, that is to say by moving the runners 57, 58 to the
right with respect to FIG. 5. After this movement, it is the
actuators 59 and 60 that move the cutting tools 72, 73 closer
together, causing the cutters of the tool 73 to protrude in order
to cause them to enter the grooves in the cutting anvil tool 73,
cutting as it passes the portion of sheath G corresponding to the
portions welded before. It can be seen from FIG. 6 that the welded
portions and the cut portions are used to connect together the two
portions already welded by the electrodes 38, 39 (FIG. 2) and cut
by the cutters 42, 43, on each side of the space 40 left free to
allow the passage of the liquid feed pipe 41. However, whereas the
first welding and cutting station 3 performs the welding and
cutting operations on two successive bags respectively, the second
welding and cutting station 4 performs welding then cutting of two
lower and upper parts respectively of two successive bags
simultaneously. At the same time, the lower bag, the upper part of
which has been welded, is separated from the sheath G after the
cutting operation.
[0052] Once cutting is over, the actuators 59, 60 are returned
backward, and then it is the turn of the actuators 53, 54 to be
returned backward. At the same time, at the end of this welding and
cutting operation of the second welding and cutting station 4, the
sheath G is lowered by a spacing corresponding to the height of a
bag, so that the first welding and cutting station 3 can recommence
its operating cycle.
[0053] While the first welding and cutting station 3 is performing
its operations, the chassis 47 of the second welding and cutting
station 4 is returned upward by one spacing by the linear motors
50, 51.
[0054] It is also during this space of time that the operations of
puncturing and loading the straw 2 which we shall now describe are
performed, it being understood that these operations are also
performed on a stationary sheath. Once the sheath G has been moved
by the second welding and cutting station 4, a valve V finds itself
aligned in the continuation of the diameter of the transfer disk
78. A slide 82 bearing a perforator 84 is positioned in the
diameter of the transfer disk 78 aligned with the passage of the
valve V. The four actuators 92, 93, 93a (the actuator 92a not being
visible) push the bearing surfaces 89, 90 against each other and
against the fixed support surfaces 87, 88 on each side of the valve
V. The intermediate bearing surface 91 is clamped between the
bearing surface 90 and the support surface 88. The various layers
of film forming the sheath G are thus held firmly on each side of
the valve V.
[0055] The actuator 96 pushes the radial slide 82 toward the valve
V so that the perforator 84 perforates the film that was closing
the entry to the passage in the valve V. It will be recalled that,
in this example, the sheath G and the valve V are assumed to have
been configured as described in EP-0 948 446 to which reference may
be made. However, the invention may also obviously be applied to
other types of bags equipped with valves. When the actuator 96
retreats, the return springs 83 return the slide 82 backward, with
the perforator 84.
[0056] The motor 80 then drives the transfer disk through one
spacing, in this example this spacing corresponding to 30.degree.,
thus placing the next slide 82 bearing a straw P on the line
connecting the center of the transfer disk 78 to the passage in the
valve V. The actuator 96 is once again actuated to push the slide
82 and engage the straw P in the passage in the valve V. Once the
engagement of the straw P is over, the four actuators 92, 93, 93a
(actuator 92a not being visible) retreat, releasing the layers of
film of the sheath G.
[0057] At the same time as the operation of loading a straw P into
the passage in the valve, the pusher 99 diametrically opposite the
valve V with respect to the transfer disk is also actuated to push
a straw P into the diametrically opposite slide 82.
[0058] As this operation of puncturing and of loading the straw P
are performed at the same time as the operation of the first
welding and cutting station 3, a further cycle of the second
welding and cutting station 4 with the pulling of the sheath G can
restart.
* * * * *