[0001] The present invention relates to a wrapping unit designed for the packaging mainly
of chocolates, candy, small pastries and the like, hereinafter generically termed
products.
[0002] Packaging devices are known which provide for covering each individual product with
a sheet made of a material preferably chosen among polymeric, metallic, paper and
combinations thereof.
[0003] The flaps of this covering sheet can be mutually sealed (cold or with heat) for better
isolation of the contained product and a consequent protection thereof against atmospheric
and environmental agents.
[0004] In particular, devices of the known type provide for the shaping of a tubular covering
for the product (obtained by wrapping the sheet around the product itself) in which
a notch is preferably provided which ensures the possibility to open the package easily
on the part of the user.
[0005] This technical solution is described in European patent No.
1888410.
[0006] This solution does not allow to achieve complete packaging of the product and therefore
requires in subsequent stations the execution of subsequent closure processes.
[0007] The further closure stations of the known type are not versatile and are therefore
suitable to perform a single type of packaging.
[0008] It is furthermore appropriate to specify that wrapping machines of the known type
are also particularly specific: each of them is normally designed to provide a single
type of wrapping; the poor versatility of machines of the known type makes them less
appealing for potential clients.
[0009] WO 2014/097235 discloses a method for packaging articles to form a tubular wrapping of thermosealable
sheet material inside which the articles to be packaged are prearranged, regularly
distanced, and to feed the tubular wrapping to a cut station at which grip means,
suitable to grasp in succession the articles, operate. The transverse cut of the tubular
wrapping is performed in suitable step relationship in the section upstream the article
grasped by the grip means and the prepackaged article is transferred to a closure
rotatable head for closing the package, rotatable at a plurality of operative stations.
In a first operative station the bellows folding of the open ends of the portion of
tubular wrapping containing the article is performed. Successively, the sealing of
the bellows folded ends of the wrapping is performed to obtain the airtight closure
of the package.
[0010] The aim of the present invention is to solve the problems described above, providing
a wrapping unit that is versatile and therefore suitable to generate wrappings with
different characteristics on the processed products.
[0011] Within the scope of this aim, an object of the invention is to propose a wrapping
unit in which format changing operations are particularly easy.
[0012] Another object of the invention is to propose a wrapping machine that is versatile.
[0013] A further object of the present invention is to provide a wrapping assembly and a
wrapping machine that have modest costs, are relatively simple to provide in practice
and safe in application.
[0014] In accordance with the invention, there is provided a wrapping unit as defined in
independent claim 1 and a wrapping machine as defined in independent claim 2. Further
advantageous features are defined in the dependent claims.
[0015] Further characteristics and advantages of the invention will become better apparent
from the description of a preferred but not exclusive embodiment of the wrapping unit
according to the invention, illustrated by way of nonlimiting example in the accompanying
drawings, wherein:
Figure 1 is a schematic top view of a wrapping unit according to the invention prior
to the clamping of a tubular blank that contains a product;
Figure 2 is a schematic top view of a wrapping unit according to the invention during
the clamping of a tubular blank that contains a product;
Figure 3 is a schematic side view of a wrapping unit according to the invention during
the clamping of a tubular blank that contains a product.
[0016] With particular reference to the figures cited above, a wrapping unit is generally
designated by the reference numeral 1.
[0017] The wrapping unit 1 comprises at least one gripper 2 which is provided with mutually
opposite jaws 3 for clamping at least one end of a tubular blank A that contains a
product B to be packaged.
[0018] It is necessary to specify that at least one of the jaws 3 comprises at least one
air extraction unit 4 to extract air from the inside of the tubular blank A simultaneously
with its clamping.
[0019] The adoption of a unit 1 provided with a single gripper 2 allows to provide so called
"singletwist" wrappings (generally termed "twist on top" wrappings), in which the
product B is in contact with a closed base of the wrapping sheet (the blank A is therefore
closed at one end and is not a tubular element provided with a through opening) and
its open tubular portion is clamped by the gripper 2 and subsequently (in a subsequent
station) subjected to twisting (rolling up onto itself with respect to its own axis).
[0020] According to an embodiment that is particular efficient and suitable to provide the
wrapping termed "double twist" (i.e., in which the ends of the tubular blank are both
open, upstream and downstream of the product B, and are subsequently rolled up onto
themselves in a station arranged downstream of the unit 1), the grippers 2 can validly
be at least two, which face each other.
[0021] The grippers 2 are mutually arranged at a distance that is substantially similar
to the length of the tubular blank A, so that when the blank A is arranged between
them its portions that protrude externally with respect to the product B are aligned
with the jaws 3 (which close, clamping them).
[0022] In particular, a first gripper 2 is preset to clamp a portion of the tubular element
A that is arranged upstream of the product B contained therein, while a second gripper
2 is preset to clamp a portion of the tubular element A arranged downstream of the
product B contained therein.
[0023] The tubular blank A comprises, along its internal surface, areas that can be sealed.
[0024] Upon the clamping of the upstream portion or of the downstream portion of the product
B on the part of the at least one gripper 2, the sealable areas that are internal
to said portion make mutual contact and mate.
[0025] Generally speaking, sealable areas are adopted which are constituted by layers of
adhesive (which can be active at room temperature or can be activated after heating
or following clamping) which ensure perfect cohesion of the affected surfaces, with
consequent isolation and segregation of the product B within the tubular blank A after
the clamping performed with the grippers 2.
[0026] With particular reference to a constructive solution of unquestionable interest in
practice and in application, at least one jaw 3 of each gripper 2 can comprise effectively
an air extraction unit 4 for extracting air from the inside of the tubular blank A
simultaneously with its clamping.
[0027] This air extraction allows greater stability and more uniform distribution of the
covering with respect to the product B (the tubular element A tends to cover the product
B by following its shape and replicating its contour) and minimizes the problems linked
to oxidation and perishing of the product itself (the absence of air preserves the
product B against potential contaminations or deteriorations).
[0028] According to the invention, the at least one jaw 3, more precisely the air extraction
unit 4 thereof, comprises an oscillating terminal clamp 5, intended to abut against
the tubular blank A.
[0029] The air extraction unit 4 is in fact operational by virtue of the sliding of the
clamps 5 on the surface of the tubular blank A (as close as possible to the product
B): progressively, the clamps 5 move into mutual contact, compressing the tubular
blank A and therefore in practice eliminating the air.
[0030] The clamp 5 is pivoted to the respective jaw 3 with respect to a pivot 6: the clamp
5 can oscillate freely or can be controlled by a respective actuator.
[0031] More specifically, elastic means are arranged which are designed to keep the clamp
5 in a rotated configuration of maximum distance from the respective jaw 3: upon the
clamping of the gripper 2, the terminal end of each clamp 5 is the first part of the
jaw 3 that makes contact with the tubular blank A, facilitating the stretching of
the sheet (which constitutes the blank A) along the product B and the exit of the
air that is present between them; therefore it ensures the provision of a covering
that perfectly replicates the shapes of the product B.
[0032] According to a constructive hypothesis of unquestionable interest in application,
the at least one jaw 2 comprises a heater 7 for increasing the temperature of a surface
thereof that abuts against the tubular blank A.
[0033] The clamping of a portion of the blank A on the part of the gripper 2 provided with
at least one jaw 3 that has a heated portion causes the heat-sealing of the portions
(of the flaps) of the tubular blank A that are mutually pressed against each other.
[0034] It has thus been shown that even in the case of sealable areas that are constituted
by layers of adhesive that can be activated by heat it is possible to ensure optimum
packaging.
[0035] Furthermore, it is specified that it is possible (by adopting sheets made of thermoplastic
material) to utilize the natural capacity of said material for thermal bonding, without
the need to add additional sealable layers along the internal surfaces of the tubular
blank A.
[0036] The present invention is also suitable to form an entire wrapping machine which comprises
a packaging carousel provided with a plurality of consecutive stations.
[0037] In particular, the carousel comprises a first forming station.
[0038] The forming station is provided with grip means for receiving the product B from
a supply unit and with mutual coupling elements for the flaps of a covering sheet.
[0039] In particular, the packaging sheet is conveniently arranged between the grip means
and the supply unit. The grip means therefore clamp the product B with the interposition
of the packaging sheet, forming a partial wrapping of the product on the part of said
sheet.
[0040] The coupling elements mutually join the protruding flaps of the sheet that is partially
wrapped around the product B until they constitute a tubular blank A that contains
the product.
[0041] The carousel further comprises, downstream of the forming station, a wrapping unit
1, which comprises at least one gripper 2 that is provided with mutually opposite
jaws 3 for the clamping of at least one end of the tubular blank A that contains a
product B to be packaged (blank A provided by the forming station in a preceding step).
[0042] At least one of the jaws 3 comprises, in this case, at least one air extraction unit
4 for extracting the air from the inside of the tubular blank A simultaneously with
its clamping.
[0043] The carousel further comprises a twisting station, arranged downstream of the wrapping
unit 1, which comprises at least one rotatable pair of pincers which is preset to
clamp at least one of the ends of the tubular blank A that contains the product B
and is closed at at least one end.
[0044] The twisting station performs the function of rolling onto itself the at least one
end of the tubular blank A that is arranged upstream and/or downstream of the product
B contained therein.
[0045] The carousel comprises, finally, an expulsion station that is designed to deliver
the product A wrapped within the closed and partially rolled up sheet to a predefined
exit area.
[0046] It is specified that the coupling elements that are present in the forming station
and at least one of the mutually opposite jaws 3 of the forming unit 1 can validly
comprise respective heaters 7 for the heat-sealing of the flaps of sheet that are
clamped and juxtaposed by them.
[0047] If adhesive layers that are active even at ambient temperature are arranged on the
sheet flaps, it is not necessary to have the heaters 7 (or it is possible to deactivate
them if the machine comprises them anyway).
[0048] Furthermore, the coupling elements of the forming station can comprise effectively
a blade for cutting the flaps of the sheet that are clamped by them.
[0049] Such blade is movable between a retracted configuration, at an arrangement of mutual
separation of the coupling elements, and a protruding configuration, at an arrangement
of mutual abutment of the coupling elements.
[0050] This generates an incision at the clamping region of the juxtaposed flaps of the
sheet, creating a point for easy opening of the wrapping for the end user.
[0051] It is specified that in the machine according to the invention the wrapping unit
1 can validly comprise at least two grippers (ensuring the possibility to provide
wrappings of the so-called "double-twist" type), which face each other and are arranged
at a mutual distance that is substantially similar to the length of the tubular blank
A.
[0052] As already described earlier, a first gripper 2 is preset to clamp a portion of the
tubular element A arranged upstream of the product B contained therein, a second gripper
2 is preset to clamp a portion of the tubular element A arranged downstream of the
product B contained therein.
[0053] In order to ensure that the machine according to the invention generates a wrapping
that is aesthetically pleasant and suitable for a close-fitting covering of the product
B, at least one jaw 3 of each gripper 2 comprises at least one air extraction unit
4 for extracting the air from inside the tubular blank A simultaneously with its clamping.
[0054] Advantageously, the present invention solves the previously described problems, proposing
a wrapping unit 1 that is versatile and therefore suitable to generate wrappings with
different characteristics on the processed products.
[0055] As shown, the unit 1 in fact allows to provide wrappings of the type known as "double
twist", and in general sealed wrappings.
[0056] Usefully, the wrapping unit 1 ensures that the format changing operations are particularly
easy: the unit in fact has a structure that is simple and can be disassembled easily
by any specialized operator.
[0057] Conveniently, the wrapping machine according to the invention also is versatile,
allowing the provision of wrappings of various shapes and of the sealed type.
[0058] Validly, the present invention defines a wrapping unit 1 and a wrapping machine that
are relatively simple to provide in practice and have modest costs, such as to render
them technical solutions of assured application.
[0059] The invention thus conceived is susceptible of numerous modifications and variations,
all of which are within the scope of the appended claims; all the details may further
be replaced with other technically equivalent elements.
[0060] In the exemplary embodiments shown, individual characteristics, given in relation
to specific examples, may actually be interchanged with other different characteristics
that exist in other exemplary embodiments.
[0061] In practice, the materials used, as well as the dimensions, may be any according
to the requirements and the state of the art.
[0062] Where technical features mentioned in any claim are followed by reference signs,
those reference signs have been included for the sole purpose of increasing the intelligibility
of the claims and accordingly such reference signs do not have any limiting effect
on the interpretation of each element identified by way of example by such reference
signs.
1. A wrapping unit, comprising at least one gripper (2) provided with mutually opposite
jaws (3) for clamping at least one end of a tubular blank (A) that contains a product
(B) to be packaged, at least one of said jaws (3) comprising at least one air extraction
unit (4) for extracting the air from the inside of said tubular blank (A) simultaneously
with its clamping, said grippers (2) being at least two, which face each other and
are arranged at a mutual distance that is substantially similar to the length of said
tubular blank (A), a first gripper (2) being preset to clamp a portion of said tubular
element (A) that is arranged upstream of the product (B) contained therein, a second
gripper (2) being preset to clamp a portion of said tubular element (A) located downstream
of the product (B) contained therein, at least one of said jaws (3) of each gripper
(2) comprising at least one air extraction unit (4) for extracting the air from the
inside of said tubular blank (A) simultaneously with its clamping, at least one of
said jaws (3) comprising a heater (7) for increasing the temperature of a surface
thereof that abuts against said tubular blank (A), the clamping of a portion of the
blank (A) on the part of said gripper (2) provided with at least one jaw (3) having
a heated portion producing the heat-sealing of the flaps of the tubular blank (A)
that are mutually pressed against each other, at least one of said jaws (3) comprises
an oscillating terminal clamp (5) that is intended to abut against said tubular blank
(A), said at least one air extraction unit (4) being formed by said terminal clamp
(5) that is therefore preset to extract the air from said tubular blank (A).
2. A wrapping machine of the type comprising a packaging carousel provided with a plurality
of consecutive stations, comprising:
- a first forming station, provided with grip means for receiving a product (B) from
a supply unit and with mutual coupling elements for the flaps of a covering sheet,
between said grip means and said supply unit there being a packaging sheet, said grip
means clamping said product (B) with the interposition of said packaging sheet so
as to form a partial wrapping of said product on the part of said sheet, said coupling
elements mutually joining the protruding flaps of said sheet that is partially wrapped
around said product (B) so as to constitute a tubular blank (A) that contains said
product (B);
- a wrapping unit (1) comprising at least one gripper (2) provided with mutually opposite
jaws (3) for the clamping of at least one end of a tubular blank (A) that contains
a product (B) to be packaged, at least one of said jaws (3) comprising at least one
air extraction unit (4) for extracting the air from the inside of said tubular blank
(A) simultaneously with its clamping;
- a twisting station comprising at least one rotatable pair of pincers which is preset
to clamp at least one of the ends of said tubular blank (A), which contains said product
(B), and is closed at at least one end for rolling up said at least one end onto itself;
- an expulsion station preset to deliver said product (B) wrapped with in said sheet
at a predefined output area;
said wrapping unit (1) comprising at least two grippers (2), which face each other
and are arranged at a mutual distance that is substantially similar to the length
of said tubular blank (A), a first gripper (2) being presets to clamp a portion of
said tubular element (A) that is arranged upstream of the product (B) contained therein,
a second gripper (2) being preset to clamp a portion of said tubular element (A) that
is arranged downstream of the product (B) contained therein; and
at least one jaw (3) of each gripper (2) comprising at least one air extraction unit
(4) for extracting the air from the inside of said tubular blank (A) simultaneously
with its clamping.
3. The wrapping machine according to claim 2, characterized in that said coupling elements and at least one of said mutually opposite jaws (3) comprise
respective heaters (7) for heat-sealing the sheet flaps that are clamped and juxtaposed
by them.
4. The wrapping machine according to claim 2, characterized in that said coupling elements comprise a blade for cutting the flaps of said sheet clamped
by them, said blade being movable between a retracted configuration, at an arrangement
for mutual separation of said coupling elements, and a protruding configuration, at
an arrangement for mutual abutment of said coupling elements with consequent clamping
of said juxtaposed flaps of said sheet.
1. Eine Verpackungseinheit umfassend mindestens einen Greifer (2) ausgestattet mit einander
gegenüberliegenden Backen (3) zum Festklemmen von mindestens einem Ende eines rohrförmigen
Rohlings (A), der ein Produkt (B) enthält, das verpackt werden soll, wobei mindestens
eine der genannten Backen (3) mindestens eine Luftextraktionseinheit (4) umfasst zum
Extrahieren der Luft aus dem Inneren des genannten rohrförmigen Rohlings (A) gleichzeitig
mit seinem Festklemmen, wobei die genannten Greifer (2) mindestens zwei sind, welche
einander gegenüber stehen und mit einem gegenseitigen Abstand angeordnet sind, der
im Wesentlichen gleich ist zu der Länge des genannten rohrförmigen Rohlings (A), wobei
ein erster Greifer (2) voreingestellt ist, um einen Teil des genannten rohrförmigen
Elements (A), das stromaufwärts von dem Produkt (B), das darin enthalten ist, angeordnet
ist, zu greifen, wobei ein zweiter Greifer (2) voreingestellt ist, um einen Teil des
genannten rohrförmigen Elements (A),das stromabwärts von dem Produkt (B), das darin
enthalten ist, angeordnet ist, zu greifen, wobei mindestens eine der genannten Backen
(3) von jedem Greifer (2) mindestens eine Luft Extraktionseinheit (4) zum Extrahieren
der Luft aus dem Inneren des genannten rohrförmigen Rohlings (A) gleichzeitig mit
seinem Festklemmen umfasst, wobei mindestens eine der genannten Backen (3) ein Heizelement
(7) umfasst zum Erhöhen der Temperatur einer Oberfläche davon, welche gegen den genannten
rohrförmigen Rohling stößt, wobei das Festklemmen eines Teils des Rohlings (A) auf
dem Teil des genannten Greifers (2) bereitgestellt ist mit mindestens einer Backe
(3) die einen erhitzten Teil hat, welcher das Heißversiegeln der Klappen des rohrförmigen
Rohlings (A) erzeugt, welche gegenseitig aneinander gepresst werden, wobei mindestens
eine der genannten Backen (3) eine oszillierende Anschlussklemme (5) umfasst, die
gegen den genannten rohrförmigen Rohling (A) anstoßen soll, wobei die mindestens eine
Luftextraktionseinheit (4) durch die genannte Anschlussklemme (5) gebildet wird, die
deshalb voreingestellt ist, um die Luft aus dem rohrförmigen Rohling (A) zu extrahieren.
2. Eine Verpackungsmaschine vom Typ umfassend ein Verpackungskarussell bereitgestellt
mit einer Vielzahl von aufeinander folgenden Stationen, die Folgendes umfasst:
- eine erste Formstation, bereitgestellt mit Eingriffmitteln zum Aufnehmen eines Produkts
(B) von einer Zuführeinheit und mit gegenseitigen Kopplungselementen für die Klappen
eines Deckplatzes, wobei zwischen den genannten Eingriffsmitteln und der genannten
Zuführeinheit eine Verpackungsfolie ist, wobei die genannten Eingriffsmittel das genannte
Produkt (B) mit der Einfügung der genannte Verpackungsfolie festklemmen, um ein teilweises
Verpacken des genannten Produkts auf dem Teil der genannten Folie zu bilden, wobei
die genannten Kopplungselemente gemeinsam die vorstehenden Klappen der genannten Folie,
die teilweise um das genannte Produkt (B) herumgewickelt ist, verbinden, um einen
rohrförmigen Rohling (A) zu bilden, der das genannte Produkt (B) enthält;
- eine Verpackungseinheit (1) umfassend mindestens einen Greifer (2), bereitgestellt
mit einander gegenüberliegenden Backen (3) für das Festklemmen von mindestens einem
Ende eines rohrförmigen Rohlings (A), der ein Produkt (B) enthält, das verpackt werden
soll, wobei mindestens eine der genannten Backen (3) mindestens eine Luftextraktionseinheit
(4) umfasst, zum Extrahieren der Luft aus dem Inneren des genannten rohrförmigen Rohlings
(A) gleichzeitig mit seinem Festklemmen;
- eine Abdrehstation umfassend mindestens ein rotierbares Paar von Zangen, welche
voreingestellt sind, um mindestens eines der Enden des genannten rohrförmigen Rohlings
(A) festzuklemmen, welcher das genannte Produkt (B) enthält, und es wird an zumindest
einem Ende geschlossen, zum Aufrollen des genannten mindestens einen Endes auf sich
selbst;
- eine Auswurfstation, voreingestellt, um das genannte Produkt (B) eingepackt innerhalb
der genannten Folie an einem vordefinierten Ausgabebereich zu liefern;
wobei die Verpackungseinheit (1) mindestens zwei Greifer (2) umfasst, welche sich
gegenüberliegen und in einem gegenseitigen Abstand angeordnet sind, der im Wesentlichen
gleich ist zu der Länge des genannten rohrförmigen Rohlings (A), wobei ein erster
Greifer (2) voreingestellt ist, um einen Teil des genannten rohrförmigen Elements
(A) festzuklemmen, der stromaufwärts von dem Produkt (B) das darin enthalten ist,
angeordnet ist, wobei ein zweiter Greifer (2) voreingestellt ist, um einen Teil des
genannten rohrförmigen Elements (A) festzuklemmen, das stromabwärts von dem Produkt
(B), das darin enthalten ist, angeordnet ist; und
wobei mindestens eine Backe (3) von jedem Greifer (2) mindestens eine Luftextraktionseinheit
(4) zum Extrahieren der Luft von dem Inneren des genannten rohrförmigen Rohlings (A),
gleichzeitig mit seinem Festklemmen, umfasst.
3. Die Verpackungsmaschine gemäß Anspruch 3, dadurch gekennzeichnet, dass die genannten Kopplungselemente und mindestens eine der genannten einander gegenüberliegenden
Backen (3) entsprechende Heizelemente (7) umfassen für das Heißversiegeln der Folienklappen,
welche durch sie festgeklemmt und nebeneinander angeordnet werden.
4. Die Verpackungsmaschine gemäß Anspruch 3, dadurch gekennzeichnet, dass die genannten Kopplungselemente eine Klinge zum Schneiden der Klappen der genannten
Folie, welche durch sie festgeklemmt wurde umfassen, wobei die Klinge zwischen einer
zurückgezogenen Konfiguration in einer Anordnung für gegenseitige Trennung der genannten
Kopplungselemente, und einer vorstehenden Konfiguration, bei einer Anordnung für gegenseitiges
Anstoßen der genannten Kopplungselemente mit anschließendem Festklemmen der genannten
nebeneinander angeordneten Klappen der genannten Folie bewegbar ist.
1. Unité d'enveloppement, comportant au moins une pince (2) pourvue de mâchoires (3)
mutuellement opposées pour serrer au moins une extrémité d'une ébauche tubulaire (A)
qui contient un produit (B) à emballer, au moins l'une desdites mâchoires (3) comportant
au moins une unité d'extraction d'air (4) pour extraire l'air de l'intérieur de ladite
ébauche tubulaire (A) simultanément à son serrage, lesdites pinces (2) étant au moins
au nombre de deux, qui se font face et sont agencées à une distance mutuelle qui est
sensiblement similaire à la longueur de ladite ébauche tubulaire (A), une première
pince (2) étant préréglée pour serrer une portion dudit élément tubulaire (A) qui
est agencée en amont du produit (B) contenu dans celui-ci, une seconde pince (2) étant
préréglée pour serrer une portion dudit élément tubulaire (A) située en aval du produit
(B) contenu dans celui-ci, au moins l'une desdites mâchoires (3) de chaque pince (2)
comportant au moins une unité d'extraction d'air (4) pour extraire l'air de l'intérieur
de ladite ébauche tubulaire (A) simultanément à son serrage, au moins l'une desdites
mâchoires (3) comportant un élément chauffant (7) pour augmenter la température d'une
surface de celle-ci qui vient en butée contre ladite ébauche tubulaire (A), le serrage
d'une portion de l'ébauche (A) sur la partie de ladite pince (2) pourvue d'au moins
une mâchoire (3) ayant une portion chauffée produisant le thermoscellage des rabats
de l'ébauche tubulaire (A) qui sont mutuellement pressés les uns contre les autres,
au moins l'une desdites mâchoires (3) comporte une pince terminale oscillante (5)
qui est destinée à venir en butée contre ladite ébauche tubulaire (A), ladite au moins
une unité d'extraction (4) étant formée par ladite pince terminale (5) qui est donc
préréglée pour extraire l'air de ladite ébauche tubulaire (A).
2. Machine à envelopper du type comportant un carrousel d'emballage pourvu d'une pluralité
de stations consécutives, comportant :
- une première station de formage, pourvue de moyens de préhension pour recevoir un
produit (B) d'une unité d'alimentation et d'éléments de couplage mutuel pour les rabats
d'une feuille de recouvrement, entre lesdits moyens de préhension et ladite unité
d'alimentation étant agencée une feuille d'emballage, lesdits moyens de préhension
serrant ledit produit (B) avec l'interposition de ladite feuille d'emballage de manière
à former un enveloppement partiel dudit produit sur la partie de ladite feuille, lesdits
éléments de couplage assemblant mutuellement les rabats en saillie de ladite feuille
qui est partiellement enveloppée autour dudit produit (B) de manière à constituer
une ébauche tubulaire (A) qui contient ledit produit (B),
- une unité d'enveloppement (1) comportant au moins une pince (2) pourvue de mâchoires
(3) mutuellement opposées pour le serrage d'au moins une extrémité d'une ébauche tubulaire
(A) qui contient un produit (B) à emballer, au moins l'une desdites mâchoires (3)
comportant au moins une unité d'extraction d'air (4) pour extraire l'air de l'intérieur
de ladite ébauche tubulaire (A) simultanément à son serrage,
- une station de torsion comportant au moins une paire de pinces rotatives qui est
préréglée pour serrer au moins l'une des extrémités de ladite ébauche tubulaire (A),
qui contient ledit produit (B), et est fermée au niveau d'au moins une extrémité pour
enrouler ladite au moins une extrémité sur elle-même,
- une station d'expulsion préréglée pour délivrer ledit produit (B) enveloppé à l'intérieur
de ladite feuille dans une zone de sortie prédéfinie,
ladite unité d'enveloppement (1) comportant au moins deux pinces (2), qui se font
face et sont agencées à une distance mutuelle qui est sensiblement similaire à la
longueur de ladite ébauche tubulaire (A), une première pince (2) étant préréglée pour
serrer une portion dudit élément tubulaire (A) qui est agencée en amont du produit
(B) contenu dans celui-ci, une seconde pince (2) étant préréglée pour serrer une portion
dudit élément tubulaire (A) qui est agencée en aval du produit (B) contenu dans celui-ci,
et
au moins une mâchoire (3) de chaque pince (2) comportant au moins une unité d'extraction
d'air (4) pour extraire l'air de l'intérieur de ladite ébauche tubulaire (A) simultanément
à son serrage.
3. Machine à envelopper selon la revendication 2, caractérisée en ce que lesdits éléments de couplage et au moins l'une desdites mâchoires (3) mutuellement
opposées comporte des éléments chauffants (7) respectifs pour thermosceller les rabats
de feuille qui sont serrés et juxtaposés par ceux-ci.
4. Machine à envelopper selon la revendication 2, caractérisée en ce que lesdits éléments de couplage comportent une lame pour couper les rabats de ladite
feuille serrée par ceux-ci, ladite lame étant mobile entre une configuration rétractée,
au niveau d'un agencement de séparation mutuelle desdits éléments de couplage, et
une configuration en saillie, au niveau d'un agencement de mise en butée mutuelle
desdits éléments de couplage avec un serrage conséquent desdits rabats juxtaposés
de ladite feuille.