FR2696710A1 - Machine for closing a container such as a tray of semi-rigid material, by means of a cover. - Google Patents

Abstract

The invention relates to a machine for closing a container (1) by means of a cover (3), comprising means (8, 11) for continuously conveying the containers, a plurality of shapers (14) each composed of at least two elements intended to cooperate to surround each container, means for driving the shapers adapted to move them in a closed loop, means (38, 39, 47, 48) for supplying the suitable covers (3) to present each cover in an inclined manner above a container (1), in a position such that said container drives this cover with it, and shaping means (30, 32) adapted to come to exert on the cover a suitable pressure in causing the assembly of the container (1) and said cover (3).

Description

MACHINE FOR CLOSING A CONTAINER

  SUCH AS A TRAY IN SEMI-RIGID MATERIAL,

BY MEANS OF A LID

  The invention relates to a machine for closing a container, such as a container made of a semi-rigid material, by means of a cover. It is particularly applicable to the closing of containers containing fruit. at present automated machines for closing trays of fruit by means of lids which snap onto said trays. Such machines include a snap-on station to which the trays are routed15 and to which a cover is lowered and press the latter on said tray in order to obtain the closing thereof. The disadvantage of such machines lies in the fact that the trays filled with fruit are frequently deformed by the latter. As a result, these trays no longer have a upper face of a form strictly conjugate with that of the covers, and

  when these are brought into contact with said trays, on the one hand, they can no longer be assembled with the latter and, on the other hand, they frequently come into contact with the fruits which they damage.

  To overcome this drawback, the applicant has developed a machine, described in patent application FR 91 08573 not published on the date of filing of this application, in which the container is initially belted, guaranteeing against any deformation of this one, then moved upwards until it meets the cover itself, surrounded by a stirrup. When closing the container, the latter and the cover therefore occupy perfectly defined relative positions. In addition, the container cannot deform, the closing operation is carried out with great reliability. However, the downside of this machine is that it works

  discontinuous, the closing operation necessitating stopping the translation of the containers, then a vertical displacement of the latter. As a result, the production rates of such a machine are relatively low.

  The present invention aims to overcome this drawback and aims to provide a machine offering the advantages of the above described, namely mainly the possibility of carrying out with great reliability the operation of closing a container, and also operating , with a high production rate. To this end, the invention relates to a machine for closing a container, such as a container made of semi-rigid material, provided with a face, called upper, open, by means of a cover of conjugate form of said upper face, said container and cover being provided with latching means able to allow their assembly, said machine being characterized in that it comprises: continuous conveying means suitable for bringing the containers individually one after the other others, a plurality of conformers each composed of at least two elements intended to cooperate to surround each container, near the upper face and over the greater part of the perimeter of said container, means for driving the elements of the conformers adapted to move them in a closed loop along which the elements of a shaper are brought on either side of a container until it comes to surround the latter er, then moved linearly so as to drive said container, and finally brought to release the container, means for supplying the covers adapted to present each cover in an inclined manner above the upper face of a container, in a position such that said container comes into contact with an end face, said upstream, of said cover and carries the latter with it, shaping means of shapes conjugated to that of the cross section of a cover, adapted to come to exercise on said lid a pressure capable of generating the assembly of the container and the lid. According to the invention, and during its progression, the container is therefore initially belted, thus guaranteeing against any deformation thereof. In a second phase, this container encounters a cover positioned so as to be driven by this container and coming to deposit on the latter without slowing down its speed of translation Finally, the assembly is carried out during the passage of the container / cover assembly in line with the conforming means of conjugate shape of the cross section of the cover. Consequently, and in the first place, the various operations leading to the closure of the container are carried out continuously, making it possible to obtain a very high yield. For example, a machine intended for closing conventional trays of fruit has a yield in the order of 3,000 trays / hour.25 In addition, during these operations, the container surrounded by a shaper cannot therefore be deformed and the closing operation is carried out with great reliability. It should also be noted that the design of this machine makes it possible to use it with containers of different size and shape, providing for this purpose removable conformers of combined shapes and dimensions of the different models of containers and lids. 35 According to another characteristic of the invention: the means for driving the conformers are arranged so as to move the latter along a horizontal trajectory situated at a height suitable for said conformers to surround the containers in an intermediate portion of their height, 5 the conveying means comprise a track on which the containers move, said

  track being interrupted upstream of the point of supply of the covers so that each container undergoes a downward movement relative to the shaping device 10 surrounding it, causing said container to find itself belted near its upper face.

  Furthermore, according to a preferred embodiment, the means for driving the conformers comprise two support chains of said conformers15 driven in a closed loop around pinions with vertical axes, said chains each supporting one of the elements of the conformers and being arranged in parallel one with respect to each other so that said elements cooperate with a view to driving the containers. Furthermore, each shaping element advantageously consists of two L-shaped parts arranged facing each other. and each carried by a support member secured to at least one link of the drive chain. In addition, according to another characteristic of the invention, the support member of each piece of a shaping element comprises a plate secured to at least one link in the chain by means of an axis, and provided with at least one finger projecting from the underside Furthermore a e30 guide track, arranged under each chain, has a support surface capable of allowing the sliding of the plates, in which is formed a groove for guiding the fingers of said plates. When it is used for closing the containers by means of lids provided with a peripheral rim, this machine preferably also comprises shaping means comprising a centering coil comprising sides adapted to grip the cover and exert pressure on the flange

of the last.

  In addition, when using this machine for the assembly of lids and containers provided with latching means respectively arranged at the end faces said upstream and downstream of said lids and containers, and advantageously : the means for supplying the lids are adapted to present them in a position such that their upstream latching means are arranged in correspondence with the upstream latching means of the containers coming into contact with said lids, the shaping means include, in downstream of the centering coil, a stirrup of conjugate section of the cross section of a cover, and means

  for driving said stirrup along a vertical axis, able to move the latter so that it comes to exert pressure on the cover, at the level of the downstream end of the latter, in order to cause the assembly of the means of 'click downstream.

  Furthermore, according to another characteristic of the invention, the means for supplying the covers comprise: an inclined ramp provided with lateral guide means adapted to center the covers with respect to the sides of the centering coil, a store of stacked covers on top of each other, arranged towards the upper end of the ramp, gripping means capable of gripping the stacked covers one by one and of depositing them on the ramp, retractable stop means arranged towards the lower end of the ramp, arranged to stop the descent of the cover located at the head of the line and occurring at said end, and means for driving the cover stopped by the retractable stop means, adapted to bring said cover into the position suitable to allow its entrainment by a container. In addition, according to a preferred embodiment: the means for driving the cover located at the head of the line comprise a push-plate arranged to come into engagement with said cover, and means for moving said push-plate suitable for move longitudinally along the ramp and orthogonally above it, a flexible stop member is arranged so as to prevent any sliding of a cover brought into the position of cooperation with a container, when the push plate n is no longer engaged with said cover, said stop member being further adapted to disappear, by the effect of its flexibility, under the thrust of a container cooperating with said cover. Finally, the machine according to the invention advantageously comprises the following equipment: weighing means for each container constituted by an electronic balance, and a container evacuation station for oversized containers, a conveyor belt for evacuating closed containers disposed of so as to take charge of the movement of said containers when they are released from the conformers, a labeling station suitable for affixing transversely, on the lid of a closed container, a label of length greater than the width of said lid arranged so to exceed on either side of the latter, support members arranged so as to be on either side of the containers, associated with vertical displacement means capable of moving them along a container of so that they fold down the ends of the labels, and that they apply these on the longitudinal sides of the closed container. Other characteristics, purposes and

  advantages of the invention will emerge from the description

  detailed description which follows with reference to the appended drawings which represent, by way of nonlimiting example, a preferred embodiment. In these drawings which form an integral part of this description:

  Figure 1 is a schematic view in longitudinal section through an axial vertical plane A of a machine according to the invention, Figure 2 is a longitudinal section through an axial horizontal plane B, Figure 3 is a cross section through a vertical plane C, Figure 4 is a cross section through a vertical plane D, Figure 5 is a cross section through a vertical plane E, Figure 6 is a cross section through a vertical plane F, Figure 7 is a cross section through a plane G representing the cover store, Figure 8 is a perspective view of one of the parts of an element of a shaper, and Figure 9 is a partial side view showing the means drive

  covers at the bottom of the inclined ramp.

  The machine shown diagrammatically in the figures is intended to ensure three operations on the trays continuously feeding this machine: a weight sorting with automatic evacuation of the trays whose weight is outside the limits set by the user, an automatic fitting of a cover , and an automatic installation of an adhesive tape. An example of a container that can be closed using this machine is shown more clearly.

  detailed in Figure 9 and consists of a tray 1 of a material such as semi-rigid plastic.

  This tray 1 has the shape of a truncated pyramid flaring upwards and has an open upper face 1 a provided on its periphery with an external peripheral return 2 of latching. The cover 3 intended to cooperate with this tray 1 is also shown in more detail in FIG. 9 and includes a peripheral snap-on rim 4 able to come over the peripheral return 2 of the tray 1 and to snap onto it. ci For this purpose, this rim 4 has snap-on studs such as 5 arranged towards each of the ends of the cover 3 and arranged internally at the base thereof in order to come to bear elastically under the return of snap-fastening 2 of the tray 1. The machine according to the invention comprises, firstly, a continuous conveying system shown in FIG. 4 This conveying system comprises a track 6 provided with an axial longitudinal slot 7, on which each tray 1 is to be manually deposited It further comprises a chain 8 with cleats 9 driven in a closed loop around two sprockets 10, 11 with horizontal axes, said chain being arranged so that the cleats 9 protrude above the track 6 through the longitudinal slot 7. Furthermore, interposed along this conveyor system, the machine comprises means for weighing each tray 1 consisting of an electronic balance 12, and an evacuation station 13 from the trays 1 out of size These weighing 12 and evacuation means 13

  being of conventional type known per se will not be described in more detail.

  Secondly, the machine comprises a plurality of shapers adapted to each belt a tray 1, coming to bear under the peripheral return 2 of the latter. These shapers consist of two elements 14, 1535 each associated with means drive adapted to move them in a closed loop along which said elements are brought on either side of a tray 1 until it surrounds the latter, then moved linearly so as to drive said tray, and finally led to release the latter. These drive means consist of two support chains 16, 17 driven in a closed loop around pinions such as 18, 19 with vertical axes. These two chains 16, 17 are also arranged so that the conformers 14, 15 surround the trays. 1 when these are on track 6 of the conveyor

  with cleats 9, downstream of the evacuation station 13.

  To this end, these chains 16, 17 are arranged parallel to each other, on either side of the end of the track 6, and in the extension of the latter. These chains 16, 17 are also arranged at a height such that the elements 14, 15 of the conformers surround the trays 1 located on track 6, substantially halfway up the latter. In this way, once these trays 1 have passed the end of the track 6, they slide downwards inside the conformers 14, 15, until the latter come to bear under their snap-back 2. As indicated above, each shaper is composed of two elements 14, 15 each associated with a drive chain 16, 17 Each element 14, 15 is further divided into two parts 14 a, 14 b, 15 a, b having the general shape of a L conjugate the shape of the angles of the trays 1, said pieces being

  arranged to be positioned at the right of each of the angles of said trays.

  As shown in FIG. 8, each part 14 a, 14 b, 15 a, 15 b of conformator is made up

  a plate 20 pierced with two oblong holes such as 21 and provided, on one side, with a longitudinal rim 22 of shape 35 conjugated with the angles of the trays 1.

  This plate 20 is secured to the chain 16 or 17 by means of a plate 23 on which it is fixed by means of screws 24 housed in the holes

oblong 21.

  The fixing of the plate 23 on the chain 16 or 17 is in turn ensured by means of two rods such as 25 projecting from said plate and locked relative to a link of said chain by means of a nut system / lock nut 26. This plate 23 is further provided, on the underside and in the extension of the rods 25, with two fingers such as 27 arranged so as to be housed in a guide groove 28 formed longitudinally in a block 29 made of plastic arranged under the path of each chain 16, 17 so as to serve as a sliding surface for each plate 23. It should be noted that the design of the conformers makes it possible, on the one hand, to easily adjust the spacing between two elements 14, 15 thanks to the oblong holes and, on the other hand, to quickly change conformers according to the shape of the trays 1 to be closed. The machine further comprises, interposed along the rectilinear path of the conformers 14, 15, conforming means of shapes conjugate to that of the cross section of a cover 3 It further comprises means for supplying the covers 3 adapted to present each cover inclined at right angles to the abovementioned shaping means, in a position such that a tray 1 comes into contact with the rim 4 of this cover, the snap-back 2 of said tray being disposed above snap-on studs 5 of said cover. 30 The shaping means comprise, first of all, and as shown in FIG. 3, a fixed coil 30 whose axis is fixed on two lateral flanges such as 31 This coil 30, d on the one hand, is arranged and, on the other hand, has flanks of shape 35 adapted to grip a cover 3 resting on a tray 1 so as to center the latter and to exert pressure on the reb ord 4 of said cover. These shaping means further comprise, as shown in FIG. 6, a stirrup 32 of conjugate section of the cross section of the covers 3, intended to be moved downwards and to exert on said cover and its peripheral rim 4, a pressure able to generate the assembly of the latching pads 5, arranged at the rear of the covers 3 with respect to the direction

for moving the trays 1.

  To this end, this stirrup 32 is carried by the end of the rod of a jack 33 arranged vertically, and the body of which is secured to a gantry 34 disposed above the movement circuit of the conformers 14, 15. In addition , two vertical rods as fixed on the stirrup 32 and slidably mounted by

  compared to gantry 34, provide guidance for this stirrup.

  In addition, the machine comprises, interposed between the coil 30 and the stirrup 32, a flexible support member 36 carried by a vertical plate 37 integral with the coil 30 As shown in FIG. 9, this support member, consisting of a brush 36, is arranged so as to serve as a bottom stop defining the position of a

  cover 3 for driving the latter by a tray 1 Furthermore, this brush 36 has a flexibility adapted so that it disappears horizontally when the trays 1 are advanced.

  The means for supplying the covers comprise, for their part, and firstly, a ramp

  inclined 38 along which the covers 3 descend by gravity, and a store 39 of stacked covers 30 disposed in the upper part of this ramp.

  As shown schematically in Figure 7, the cover store has four

  cylinders such as 40 arranged horizontally and the body of which is integral with the wall of the magazine 39, on the rods 35 of which the stack of covers rests.

  This store 39 further comprises four other jacks such as 41 arranged horizontally and arranged above the aforementioned jacks 40, so as to come into contact with the rim of the second cover of the stack, starting from the bottom, during their displacement. The store 39 comprises, finally, a jack 42 arranged orthogonally to the ramp 38 and the body of which is integral with the latter. This jack 42, arranged directly above the stack of covers 3, comprises a rod provided with a suction cup 43 adapted to allow gripping the lower cover and bringing it onto the ramp 38. The actuation of this jack 42 is carried out once the jacks 41 are deployed so as to come into contact with the edge of the second cover of the stack , and the cylinders

  retracted to allow the lower cover to descend.

  The guide ramp, for its part, as shown in FIG. 4, a chute 38 supporting the covers, comprising means for lateral guidance of the said covers made up of two rods such as 44, arranged on either side of the chute . This chute 38 is carried by a hinge pin 45 for adjusting its inclination. For example, for trays 1 as described above, the appropriate inclination of the ramp is 210. The rods 44 for lateral guidance are spaced apart so as to center the covers 3 relative to the sides of the coil 30 As shown in FIG. 9, these rods 44 extend, moreover, practically

  to the right of this coil 30, while the bottom of the chute 38 is interrupted at a distance from the brush 36 of low stop substantially less than the length of a cover 3.

  The means for supplying the covers comprise, in addition, a retractable finger 46, such as for example constituted by the end of the rod of a jack, disposed towards the lower end of the ramp 38, and 35 adapted to come and make protrusion above said ramp so as to stop the descent of the cover 3 located

at the head of the line.

  These means for supplying the covers further comprise means for driving the cover 3 stopped by the retractable finger 46, capable of bringing said cover, after withdrawal of said finger, into its low stop position against the brush 36. 5 These drive means comprise a first cylinder 47 disposed above the ramp 38 parallel to the latter. The body of this cylinder 47 is fixed to said ramp, so that its rod is oriented downwards. drive comprise, in addition, a second cylinder 48 carried by the rod of the above-mentioned cylinder 47, so as to extend orthogonally with respect to the ramp. They finally include a push plate

  49 fixed under the core of a stirrup 50 carried by the rod of the jack 48, so as to extend parallel to the ramp 38.

  This pusher plate 49 also has a transverse corrugation 51 intended to be positioned between two consecutive covers when this plate 49 is pressed against them.

  The operation of these drive means is subject to means for detecting the presence of a tray 1, such as for example one or more photoelectric cells.25 This control and the arrangement of the drive means are suitable for operate them in the following manner First, the retracted positions of the actuator 47 and the deployed position of the actuator 48 are adapted to bring the plate 49 into contact with the cover 3 stopped by the retractable finger 46 and the cover 3 located in the second position, the corrugation 51 being housed between the two covers. On the order of the detection means, the retractable finger 46 is retracted, and the jack 47 deployed so as to bring the cover located at the head of the file

  to its proper position to be driven by a tray 1.

  The jack 48 is then retracted, the retractable finger 46 having been previously deployed so as to prevent the next cover from continuing to descend. It should be noted that during the retraction of the jack 48, the cover 3 is stopped at the bottom stop by the brush 36 and cannot therefore continue its descent. Finally, the cylinder 47 is retracted then the cylinder 48 again deployed in order to start a new cycle. The machine according to the invention also comprises an endless conveyor belt 52 on which the trays 1 are brought before the elements 14, 15 of the shapers do not move apart, thus releasing said trays. 15 This conveyor belt comprises a first section 52 which is inclined upward, intended to raise the trays 1 so as to allow the peripheral return 2 to be released before the elements 14 , 15 of conformers do not deviate. Finally, the machine according to the invention comprises a labeling station for closed trays 1 moving on the conveyor belt 52. This labeling station comprises, first of all, means 53 for dispensing labels of a type known per se, adapted to affix on the cover 3, a label of length greater than the width of a tray 1, arranged so as to d spread on either side of the cover 3. This labeling station further comprises means adapted to fold the ends of the

  labels and apply them to the longitudinal sides of the closed container.

  As shown in FIG. 5, these means comprise, first of all, two horizontal brushes such as 54 fixed towards the ends of the wings of a sheet 55 of inverted U shape disposed above the conveyor belt 52. This sheet 55 and these brushes 54 are arranged so that the ends of said brushes are spaced apart by a distance less than the width of a tray 1. These means further comprise a jack 56 arranged vertically, the body of which is fixed on a portal frame 57 positioned above the conveyor belt

  52, and whose rod carries the sheet 55.

  The jack 56 is slaved so as to deploy substantially before the portion of the tray

  covered with the label does not reach its level, then10 to retract between two trays.

  Finally, a rod 58 integral with the sheet 55 and sliding relative to the gantry 57, makes it possible to guide

  this sheet during its vertical displacements.

Claims (8)

  1 / Machine for closing a container (1), such as a container made of semi-material   rigid, with a face (la), called upper, open, by means of a cover (3) of conjugate shape of said upper face, said container and cover being provided with latching means (2, 5) capable to allow their assembly, said machine being characterized in that it comprises: 10 means (6-11) of continuous conveying adapted to bring the containers (1) individually one after the other, a plurality of composite conformers each of at least two elements (14, 15) intended to cooperate to surround each container (1), near the upper face (la) and over the greater part of the perimeter of said container, drive means (16 -19) elements (14, 15) of the shapers adapted to move them in a closed loop along which the elements (14, 15) of a shaper are brought on either side of a container (1) until it comes to encircle the latter, then moved linearly rement so as to drive said container, and finally brought to release the container, means (38-51) for supplying covers (3) adapted to present each cover (3) in an inclined manner above the upper face (la) of a container (1), in a position such that said container comes into contact with an end face, said upstream, of said cover and drives the latter with it, shaping means (30, 32) of shapes conjugated to that of the cross section of a   cover (3), adapted to exert on said cover a pressure capable of generating the assembly of the container (1) and the cover (3).   2 / Machine according to claim 1, characterized in that: the drive means (16-19) of the conformers (14, 15) are arranged so as to move the latter along a horizontal trajectory situated at a height suitable for said said conformers surround the containers (1) in an intermediate portion5 of their height, the conveying means (6-11) comprise a track (6) on which the containers (1) move, said track being interrupted upstream of the point d '' brought covers (3) so that each container (1) 10 undergoes a downward movement relative to the shaper (14, 15) surrounding it, bringing said container   to be surrounded by a belt near its upper face (la).   3 / Machine according to claim 2, characterized in that the conveying means comprise a chain (8) with cleats (9) driven in closed loop   around two pinions (10, 11) with horizontal axes, said chain being arranged so that the cleats (9) protrude above the track (6), through a longitudinal slot20 (7) formed in this last.   4 / Machine according to one of the preceding claims, characterized in that the means   for shaping the shapers (14, 15) comprise two chains (16, 17) supporting said shapers driven in closed loop around pinions (18, 19) with vertical axes, said chains each supporting one of the elements (14, 15) of the conformers and being arranged parallel to each other so that   said elements cooperate with a view to driving the containers (1).   / Machine according to claim 4, characterized in that each element (14, 15) of a shaper consists of two parts (14 a, 14 b, 15 a, 15 b) in the form of L arranged opposite one on the other and   each carried by a support member (23) secured to at least one link of the drive chain (16, 17).   6 / Machine according to claim 5, characterized in that: the support member of each part (14 a, 14 b, 15 a, 15 b) of an element (14, 15) of conformator comprises a plate (23) secured to at least one link in the chain (16, 17) by means of an axis (25), and provided with at least one finger (27) projecting on the underside, a guide track (29), disposed under each chain (16, 17), has a support surface capable of   allow the sliding of the plates (23), in which is formed a guide groove (28) of the fingers (27) 10 of said plates.   7 / Machine according to one of the preceding claims for closing a container (1) by means   a cover (3) provided with a peripheral snap-on edge (4), characterized in that the shaping means15 comprise a centering coil (30) comprising sides adapted to grip the cover (3) and exert pressure on the rim (4) of the latter. 8 / Machine according to claim 7 intended for the assembly of covers (3) and containers (1) provided with latching means (2, 5) respectively arranged at the end faces said upstream and downstream of said covers and containers, characterized in that: the supply means (38-51) of the covers (3) are adapted to present them in a position such that their upstream latching means (5) are arranged in correspondence with the means d 'snap upstream (2) of the containers (1) coming into contact with said covers, the shaping means comprise, downstream of the centering coil (30), a stirrup (32) of conjugate cross section of the cross section of a cover ( 3), and drive means (33) of said stirrup along a vertical axis, capable of moving the latter so that it comes to exert pressure on the cover (3), at   the rear end of the latter, in order to cause the assembly of the downstream latching means.   9 / Machine according to one of the preceding claims, characterized in that the means for supplying   covers (3) comprise: an inclined ramp (38) provided with lateral guide means (44) adapted to center the covers (3) relative to the sides of the centering coil (30), a store (39) of covers (3 ) stacked on top of each other, arranged towards the upper end of the ramp (38), gripping means (42, 43) capable of gripping the lids (3) stacked one by one and of depositing them on the ramp ( 38), retractable stop means (46) disposed towards the lower end of the ramp (38), arranged to stop the descent of the cover (3) located at the head of the line and occurring at said end, and drive means (47-51) of the cover (3) stopped by the retractable stop means (46), adapted to bring said cover into the appropriate position to allow it to be driven by a container (1). 10 / Machine according to claim 9, characterized in that: the cover drive means (3) being at the head of the line comprise a push plate (49) arranged to engage with said cover, and means for displacement (47, 48) of said pusher plate able to move it longitudinally along the ramp (38) and orthogonally above it, a flexible stop member (36) is arranged so as to prevent sliding optional cover (3) brought into the position of cooperation with a container (1), when the pusher plate (49) is no longer in engagement with said cover, said stop member being further adapted to disappear , by the effect of its flexibility, under the push of a container (1) cooperating with said cover.   11 / Machine according to claim 10, characterized in that it comprises means for detecting the position of a container (1) capable of controlling the drive means (47-51) of the cover (3) being   at the head of the line. 12 / Machine according to one of the preceding claims, characterized in that it   comprises weighing means (12) of each container (1) consisting of an electronic balance, and a station   evacuation (13) of oversized containers. 13 / Machine according to one of the preceding claims, characterized in that it   comprises a conveyor belt (52) for evacuating the closed containers (1) arranged so as to take charge of the movement of the said containers when the latter are released from the conformers (14, 15). 14 / Machine according to one of   previous claims, characterized in that it comprises:   a labeling station (53) adapted to affix transversely, on the lid (3) of a closed container (1), a label of length greater than 25 the width of said lid arranged so as to protrude on either side of the latter, support members (54) arranged so as to be on either side of the containers (1), associated with vertical displacement means (56) able to move them along a container ( 1) so that they fold down the ends of the labels and they   apply these on the longitudinal sides of the closed container.