FR2544657A1 - METHOD AND DEVICE FOR MANUFACTURING HOLLOW BODIES COMPRISING A LOCALLY SHAPED WALL OF TWO OR MORE LAYERS - Google Patents

Abstract

THE INVENTION CONCERNS A METHOD AND A DEVICE FOR MANUFACTURING HOLLOW BODIES INCLUDING A SHAPED WALL, IN LOCATIONS, OF TWO OR MORE LAYERS. THE DEVICE FOR APPLYING COVERING LAYERS ON PREFORMS 1, INCLUDES A TRANSPORT DEVICE INCLUDING FINGERS 21 RECEIVING THE PREFORMS 1 AND WHICH DRIVES THE LATTER IN FRONT OF COVERING STATIONS 5, 6, 7, AN ACTIVATION STATION 4 OF THE EXTERNAL SURFACE OF THE PREFORMS AND A STATION 8 FOR FINAL FORMING AND EJECTION. APPLICATION IN PARTICULAR TO THE MANUFACTURE OF CONTAINERS IN THE FORM OF PLASTIC BOTTLES.

Description

The invention relates to a method and a device for making bodies

  hollow having a wall formed, at least in places, of two or more layers,

  comprising in particular a wall layer having an effect

  a blocking feature or stop feature, wherein a laminated half-finished product is first produced in accordance with the desired layered structure of the wall

  hollow bodies and from which one then forms the

said hollow body.

  It is known that in particular masked plastics, such as polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, etc. are more or less permeable to the different media and that thanks to combinations of different plastics having different values. permeability sometimes

  opposites, we can obtain a sufficient action of blocking

  in almost all environments, the blocking values of these materials being used in an additive manner. Methods are already known for manufacturing containers, in which one carries out with the aid of several extruders and by means of a particular extrusion tool,

  a laminated product in the form of a pipe or a

  as a semi-finished product, which can be se-

  the usual thermoforming processes to obtain the

containers considered.

  Processes are also known which make it possible to confer on the hollow body manufactured a blocking action or a more intense barrier effect thanks to a subsequent covering with a covering material.

  corresponding, or through a painting.

  It is further known to obtain at least one partial blocking surface, and this at least in the case

  symmetry of revolution containers, thanks to the winding

  tape of a blocking material, for example aluminum foil, but of course it is not

  not possible to cover the entire surface.

  All these processes have defects and

  disadvantages, particularly in connection with a

  mass production. This is why the invention aims to create a simple possibility, unaffected by disturbances and suitable especially for mass production, to manufacture hollow bodies having a wall provided,

  at least in places of two or more layers.

  This problem is solved according to the invention

thanks to the fact that

  first of all, preforms are

  1-layer hollow body, in the form of a demifini product, these preforms are coated with one or more layers in accordance with the desired layered structure of the wall of the finished hollow body, and forming is carried out to preforms as well

  equipped with the laminated wall structure, to obtain

the finished hollow bodies.

  Therefore, in accordance with the invention, the hollow body is manufactured in two stages, in which case it is possible, according to the purpose of use and depending on the filling material that can be accommodated in the hollow body, to treat different suitable materials.

  during lamination of the preform.

  According to the process according to the invention, the

  hollow-shaped shapes are preferably

  green layers at their outer surface.

  For the covering of the preforms, it is possible to use the most diverse methods, for example a covering in the manner of an injection molding process, a spraying of a coating material,

  immersion of the preforms in a coating material

  coating, in particular a painting of the pre-

  forms with the coating material, high vacuum or sputter deposition coating or even a coating coating of a sheet-like coating material by means of the coating method.

deep plucking.

  First, in a first step,

  can be manufactured according to known methods, by

  example by the injection molding process, a pre-

  formed of a layer that already has the dimensions

  definitive seams preferably at the body, but not yet completely formed in the next lower part of the neck and at the level of its body The preform consisting of a layer forms to a certain extent the support structure of the hollow body to be completed later, while we can realize the

  or the layers deposited on this preform, with materials

  can be selected according to the desired properties, such as characteristic properties of

  blocking or stopping or barrier, for example

  lyethylene, polyvinylidene chloride, the product de-

  signed under the acronym EVAL or others.

  The preforms covered with the layers can be stored in any manner and be heated again using known means and can be expanded in a forming station, either mechanically or at

  blowing process and are brought into their

me of definite hollow body.

  For the implementation of the method, it is particularly appropriate to use a device for affixing coating layers on body-shaped preforms.

  hollow, characterized in that a transmission device

  port, receiving preforms, can be moved step-by-step

  in front of a receiving station, at least one filling station

  and an ejection station, the transport device

  having receiving fingers engaging in the

  This device makes it possible to coat layers of preforms in a manner that is practically continuous and with a flow rate that is particularly advantageous for the manufacture of articles in large series.

  tif is characterized by particularly high security

  operating mode, a simple operating mode and significant modification capabilities, which can be

implemented quickly.

  In a preferred embodiment, in the device according to the invention it is provided at least

  between the receiving station and the first filling station

  an inter- mediate or activation

  holding devices for activating the surface to be coated with layers, preforms by mechanical, thermal, electrical or radiation action or by the deposition of a chemical activation product or

  of an adhesive agent This intermediate position used to activate

  the surface to be covered guarantees not only

  adhesion of the coating, but also allows

  preforms, which have been stored for a longer or shorter time after their manufacture, may

  be covered by a durable coating.

  For the recovery of preforms, it is pos-

  sible to provide an injection molding device in the device according to the invention, the injection molding mold has a cavity receiving a

  prefers an upper edge of the thickness of the

  to be affixed to the outer dimensions of the

  _ 3 C preforms, the thickness of the layer being variable and

  to be better adapted to the external degree of defor-

  in relation to mechanical strength as in

  possibility, the device according to the invention can

  have a spraying device for the purpose of

  the preform covering, this spraying device

  The invention is equipped with a nozzle arrangement extending over the axial length of the preform, and devices for rotating the preform about its longitudinal axis or for rotating the nozzle device around the fixed preform.

  Correspondingly, one can also

  to look at other recovery devices It's all

  it is possible to equip the device according to the

  of recovery devices of different types.

  pes, and for example in the device according to the

  a spray device for affixing a first coating and, downstream of this device, an injection molding device serving

to affix a second coating.

  The transport device can be realized at

  the way of a circular transfer table around the-

  what is the reception desk,

  several collection points and the ejection

and forming.

  Other features and benefits from there

  present invention will emerge from the description given

  hereinafter referenced to the accompanying drawings, on the

what:

  FIG. 1 represents an elevation view

  of a preform covered with a coating

  to the invention; FIG. 2 represents a sectional view on a larger scale of the wall element II of FIG. 1, FIG. 3 schematically represents a view

  in plan of a recovery device comprising a ta-

  circular transfer; FIG. 4 represents an axial section of a

  injection molding device contained in the

  FIG. 3 is a system for applying cover layers to the preforms; and

  FIG. 5 represents a device for spraying

  can be used in the device of Figure 11 and can

  to apply a covering layer to the preforms.

  FIG. 1 shows a preform 1 after covering, the contour of the untreated preform being represented in dotted line in the region of the wall 11 of FIG.

  the preform, to be shaped later

  as shown in Figure 1, the preform 1 is made with an opening piece 12 which is already identical to the opening end of a hollow body in the finished state, which must be manufactured The drawing shows in addition that the preform 1 has been coated only in the region of its wall to be shaped, but not in the region

its opening mouth 12.

  FIG. 2 shows an example of the layered structure of a treated preform. In this example, the preform has been produced by molding or by injection molding.

  it was covered with layers on its outer face Con-

  in this way, the inner layer 13 represents the

  king made for example by polyethylene (PE) or polypropylene (PP) during the injection molding of the preform and which must also be subsequently the carrier wall layer for the hollow body After activation, it was deposited on the outer surface of the

  layer of the wall 13, by spraying, a first coating

  14 which can be constituted for example by

  polyvinylidene chloride (PVDC) and presents good

  stopping or blocking characteristics On this coating

  There is deposited an outer layer 15 which may be made of polyester or polyamide so as to impart good surface properties to the hollow body.

to manufacture.

  FIG. 3 shows the diagram of a covering machine, in which the different layers are affixed in one or more stations on the preform 1. The covering machine contains, as a transport device, a circular transfer table 2, on the

  around which are arranged two fingers of reception

  These radially extending fingers 21 can be supported so that they can be rotated around them.

  their longitudinal axis and, in one or the other posi-

  tion of the circular transfer table 2, are

  in a rotational movement, as explained

  cited with reference to Figure 5.

  13 The various items used for recovery

  preforms 1 are arranged around the transfer table.

  circular feed 2 o are arranged the various positions used for covering the preforms 1 The receiving station 3 is followed, according to the direction of rotation

  1 j of the circular transfer table 2, by a station inter-

  in section 4, in which the respective preform 1 is

  tivated at its outer surface.

  can be achieved for example by means of radia-

  22, which are rotated

  turn of the preform in the direction of the arrow, but

  However, as indicated above, it is possible to

  turn the preform 1 and rotate it

  receiving finger 21 who carries it.

  After a new rotation of the trans-

  Circumstances 2 (in the example shown, a step forward

  this double), the preform, whose surface has been activated,

  reaches the first collection point 5 Confor-

  3, this first covering station 5 is occupied by an injection molding device, namely by an injection mold 24 to be

  brought under the preform 1 and by a dtex-

  The essential parts of this system of

  injection molding are reproduced in Figure 4.

  In this figure, the injection molding mold 24 has a cavity 26, 26a which is larger than the layer to be applied must be thick.

  covering material is discharged through the injection nozzle.

  the extrusion press 25 in the formed slot,

  the preformed opening mouthpiece 12 not being subjected to the ap-

  plication of a coating. Instead of the injection molding device

  could also be foreseen in the first position of

  covering a spraying device 27 according to the

  FIG. 5, for example in correspondence with FIG.

  2, first depositing by spray a barrier layer consisting of polyvinylidene chloride on the preform 1 in the region of its wall 11 to be

  later deformed Even in this case, the tip of or -

  preformed 12 is not covered with a coating.

  As shown in FIG. 5, in this example the preform 1 is rotated under the effect of the rotation of the

  receiving finger 21 carrying it, while the

  Spray 25 is made in the form of an arm

  fixed on which is arranged a row of spray nozzles

28.

  In FIG. 3 it has been indicated that a second covering station 6 and a third covering station 7 may be further arranged following the first covering station 5. In accordance with the representation of FIG.

  Figure 3; these other collection points 6 and 7 are

  of injection molding devices, that is to say

  injection molding molds 24 and presses of ex-

  From the last covering station 7, the covered preform arrives in the finalizing and ejection station 8 to be packed for transport or stored. The forming and ejection station 8 can contain forming devices by blowing

known type.

  Instead of covering with a molding by

  injection or spraying, it is also possible to

Q

  other possibilities of recovery, for example de-

  by evaporation of layers under high vacuum or immersion

  The preform can be covered with a sheet by means of the deep-drawing process. It is also possible to cover the coating material by coating the preform. used separately or in combination For this purpose,

  the device of Figure 3 makes it possible to equip the

  5 and 7 overlapping stations with the respective appropriate devices, for the desired method of recovery. It is also possible to equip the device.

  of Figure 3 with more than three cover positions.

Claims (12)

  1 Process for manufacturing hollow hollow bodies   having a wall formed, at least in places, of two or more layers, in particular having a wall layer having a locking effect or a stopping characteristic, according to which a semi-finished product is first produced laminated in accordance with the structure   desired in layers of the wall of hollow bodies and in particular   firing from which said hollow bodies are then formed, characterized   in that the single-layer hollow body preforms (1) are first produced in the form of a semi-finished product, these preforms are covered with one or more layers ( 1) in accordance with the desired layered structure of the wall of the finished hollow body, and forming the preforms as well as   equipped with the laminated wall structure, to obtain the finished hollow bodies.   Process according to claim 1, characterized   in that the preforms (1) in the form of hollow bodies are   covered with layers at their outer surface.   3. Process according to any one of the claims   1 and 2, characterized by overlapping the preforms (1) with layers in accordance with an injection molding process, in which the forms are introduced.   individually in corresponding injection molds.   Process according to any one of the claims   1 to 3, characterized by a preform overlap   (1) by spraying a coating material with   is lying. Process according to any one of the   cations 1 to 4, characterized by a recovery of   forms (1) by immersion in the covering material is lying.   Process according to any of the claims   cations 1 to 4, characterized by a recovery of   forms (1) by coating, in particular painting with the covering material.   Process according to any one of the claims   cations 1 to 6, characterized by a recovery of pre-   (1) by high vacuum evaporation deposition or at   using a sputtering process.   Process according to any one of the claims   cations 1 to 7, characterized by a recovery of   forms (1) by depositing a covering material in the form of   sheet by means of the recovery process.   Process according to any one of the   1 to 8, characterized in that the preforms (1)   are made with an opening end, (12), whose-for-   and the dimensions are equal - at least in one   ge measurement to those of the opening end of the finished hollow bodies, and that the mouthpiece is not   subject to overlapping operatiol.   Process according to any one of the   1 to 9, characterized in that the preform is made by injection molding and that during this operating phase the carrier wall layer of the body hollow is prepared.   11 Device for covering preforms   shaped hollow body during the implementation of the   assigned according to any one of claims 1 to 10,   characterized in that a transport device, receiving   before the preforms (1), can be moved step-by-step   before a reception station (3), at least one   cover (5) and an ejection station (8), the device   carrying fingers with receiving fingers (21)   gaging inside the preforms.   Device according to claim 1 or 11, characterized in that at least between the receiving station   (3) and the first covering station (5) is located   having regard to an intermediate station (4) which contains devices for activating the surface, to be covered with layers, of the preforms (1) by mechanical, thermal, electrical or radiation action or by means of   chemical activation product or an adhesion sive.   13 Apparatus according to any one of the   11 and 12, characterized by a device for   injection molding used to coat the layers   forms (I) and in which the injection molding mold (24) has a cavity (26, 26 a) receiving a preform and   the size is greater, the thickness of the layer   to be deposited, to the outer dimensions of the preforms.   14 Apparatus according to any one of the   11 to 13, characterized by a spraying device   for covering the preforms (1) and comprising   a nozzle device (10) extending over the axial length   the respective preform (1), and devices   to rotate the preform (1) around its axis   to rotate the nozzle device (10) tower of the preform (1) fixed.   Device according to any one of the   1 to 14, characterized in that the transport device is constructed in the manner of a circular transfer table (2) around which the receiving station (3) is arranged, the covering station (5), preferably   several collection points (5,6,7), and the ejection station tion (8).