FR2474943A1 - METHODS FOR MANUFACTURING RECEPTACLES, PARTICULARLY OF THE DISPOSABLE TYPE, AND RECEPTACLES THUS OBTAINED - Google Patents

Abstract

TO PRODUCE A RECEPTACLE, A STRIP 9 OF PLASTIC MATERIAL IS MOLDED IN A WAY THAT THE STRIP SHAPES A RECEPTACLE PROVIDED WITH A LIQUID-TIGHT SIDE WALL, THE FORMED RECEPTACLE BEING DETACHED FROM THE REST OF THE STRIP BY MEANS OF ASSOCIATED ELEMENTS 13 MOVING WITHIN THE OTHERS, ONE OR MORE OPENINGS BEING SIMULTANEOUSLY FORMED (AT 14) IN THE BASE OF THE RECEPTACLE, A FILTERING DISC BEING INSIDE THE RECEPTACLE.

Description

Processes for manufacturing receptacles, in particular of the disposable type, and

receptacles thus obtained

The present invention relates to the field of receptors.

tackles, and more particularly disposable receptacles.

  There is a need for inexpensive receptacles, and in particular partially permeable receptacles intended to constitute inserts used to make a

  filtering or controllable separation, and to be useful

read as (read filters in industrial processes, as well as in air cleaning installations, such as air filters for motor vehicles, in percolation or filtering systems, or in all other types of separating devices There is also a need for receptacles used as pots for

flowers or plants.

  According to the invention, a method of manufacturing is proposed.

  cation of a receptacle comprising the steps of molding a strip of plastic material in a molding tool or mold at a molding station so that the strip forms a receptacle having a liquid-tight side wall, and cutting the receptacle thus formed from the rest of the strip by means of associated elements and moving with respect to each other, characterized in that during or after the molding step, the receptacle is provided with a permeable or semi-permeable base part. These receptacles can be molded from a strip of thermo-plastic material which is heated and which is

  intermittently advances in the machine station

lage, one or more molding tools being preferably brought into the operating position at the molding station so as to be able to mold a receptacle therein, while at the same time molding or forming tools which were previously in the molding station are moved to a discharge position so that the receptacles

molded inside can be removed. Advantageous-

  The molding tool may comprise a recess in a tool, means being provided for creating a vacuum in the recess so that the strip of material is formed under vacuum. Advantageously, this receptacle is cut from the strip by a cutting blade cooperating with an elastic abutment surface in the molding tool, and preferably the cutting blade is heated. In one embodiment of the method, a receptacle comprising a base which forms an integral part thereof is formed while perforations are formed in the base of the receptacle. The perforation step of the base can be carried out in the molding tool and by means of heated tips cooperating with an elastic abutment surface which

is part of the molding tool. Preferably, the opera-

  perforation is performed simultaneously with the operation

tion of cutting the molded receptacle from the rest of the strip. Alternatively, the perforation operation can be performed by

ultrasound against a rigid support surface.

In another embodiment of the method, the base of the receptacle is embossed in whole or in part in the molding tool, and the embossing can be carried out at the same time as the receptacle is detached by cutting out the rest of the bandaged. Preferably, the base of the receptacle is stamped by means of a cutting edge cooperating with an elastic abutment surface of the molding tool. The base of the recess of the molding tool in which the receptacle is formed may be provided with an opening and means may be provided for connecting the opening to a source of vacuum or of partial vacuum, so that after stamping the base of the receptacle the cut base can be removed from the molding tool by vacuum or by partial vacuum. Preferably, a control valve or flap is provided between said opening and the source of vacuum or partial vacuum. While the perforations or openings formed in the base of the receptacle make it permeable, it is preferable that the perforations or openings formed in the base of the receptacle be covered by an element permeable to gases or liquids, such as an element of filter consisting of filter paper which can be fixed to the receptacle by heat-sealing or by gluing. Preferably, the method comprises the steps consisting in producing a receptacle provided with a peripheral bulge directed towards the outside and situated at a certain distance from the top of the receptacle to facilitate its stacking. The method may also include the step of providing the receptacle with rigid protrusions and extending substantially horizontally outward, the receptacle thus formed may be suitable as a tea strainer, coffee infuser or the like. The receptacle can also be provided with reinforcing or stiffening members extending along the base of said receptacle, and it is preferably provided at its upper part with a flange

device extending radially outward.

  The present invention also relates to a receptacle insofar as it is manufactured by means of a process such

as described above.

The invention will be better understood on reading the

description which follows in which reference is made to the drawings

annexed in which: fig. 1 is a perspective view of a receptacle produced according to the invention, with a permeable base and with a cut-out part, FIG. 2 is a plan view of the receptacle shown in FIG. 1, fig. 3 is a vertical section view showing the molding and forming tool and also representing a stamping tool cooperating with the previous one, these tools being used for the production of a receptacle as shown in FIGS. 1 and 2, fig. 4 is a vertical section of part of the molding tool shown in FIG. 3, fig. 5 is a vertical section of the molding tool of FIGS. 3 and 4, showing another tool intended to introduce a prefabricated porous base element into the receptacle, FIG. 6 is a vertical sectional view corresponding to FIG. 5, showing how the other tool can cooperate with

a punch or a stamp for the preparation of the element

  prefabricated porous base, fig. 7 is a view in vertical section of another tool for manufacturing receptacles according to the invention, showing how the receptacles are provided with a perforated base, FIG. 8 is a perspective view of an inverted receptacle, produced on the tool illustrated in FIG. 7,

fig. 9 is a perspective view of another receptacle

tackle made according to the invention,

fig. 10 is a perspective view of another receptacle

still tackle, produced according to the invention, this receptacle consisting of a tea strainer, and

fig. It is a perspective view of another reception-

  tackle again, produced according to the invention and intended to be

  used as a flowerpot or plant pot.

  Reference being made to the accompanying drawings, we will begin by describing a receptacle provided with a permeable base and

manufactured according to the invention with reference to figs. 1 and 2.

  The receptacle 1 is circular in plan and comprises a side wall which tapers in a conical manner, from a flange or an upper flange 2 directed radially outwards, in the direction of a flange or a lower rim 3 extending radially towards

  the interior. The wall 1a is made of a thermo-material

  plastic and it is homogeneous but not permeable. Thus, the wall is gas and liquid tight. The flange or the rim 3 directed inwards defines a circular opening 4 in the middle of the base of the receptacle 1. A circular disc made of a material permeable to gases or liquids, such as a disc made of porous paper or

  analogous, and having a larger diameter than the diameter

opening 4 meter, is fixed to the collar-3 by means of

  an adhesive or by heat sealing its perimeter

  ring on collar 3, so as to close the opening

  ture 4. The disc 5 serves, in this receptacle, as an element for

filtering.

Whereas, in the receptacle illustrated in figs. 1 and 2,

  the opening 4 formed in the base of the receptacle is covered

  green by a material permeable to gases or liquids, it will be understood that a receptacle produced according to the invention can

  simply include an exposed opening that can extend

  dre on the entire base surface, or only on a part of the base surface, or alternatively that the base surface of the receptacle is provided with a series of small openings or perforations. Thus, the side wall and the base of the receptacle can be made in the form

  of a unitary assembly, for example of a thermo-material

plastic, the base of the receptacle being provided with a large number of small perforations by means suitable during the forming or molding step, or after this step. Having thus described the products manufactured using the methods of the present invention, a particular method will now be described with reference to the drawings in FIGS. 3 to 5

attached drawings.

Fig. 3 represents a vacuum forming tool 7.

The tool includes a recess in its upper surface and

it is provided with pipes 8 communicating with the hollow

  and used to extract air from the recess. When using the tool, it heats and intermittently advances a strip 9 of thermoplastic material towards

the illustrated molding station o, as will be described below

  afterwards, it is hot molded and stamped by means of

  associated elements moving relative to each other.

  In a preferred embodiment of such a machine implementing the method according to the invention, two molding tools 7 are used, one tool being brought into the operating position at the molding station which is used for the manufacture of the receptacle , while the second molding tool is moved simultaneously to a discharge station where the receptacle made in the tool is removed from the tool. However, and referring again to FIG. 3, when the heated strip of thermoplastic material 9 is brought to the molding station, and when air is drawn in

  outside the recess defined in tool 7 by the pipes

8, the heated material is sucked inside the recess and thus adopts the configuration corresponding to

that of the recess which, of course, is the configuration

tion of the receptacle. As can be seen in fig. 3, two grooves are formed in the tool 7, one groove being located on the upper surface of the tool which surrounds the periphery of the recess and the other being formed in the part of the tool defining the recess. The grooves contain inserted elements made of an elastic material 10, 11. A stamping tool 12, suitable for stamping and cutting the strip of thermoplastic material 9 once

  that it has been molded, is also planned. The estam tool

page and cutting 12 includes two circular cutting blades

res 13, 14. The cutting blade 13 is aligned with

  the elastic element 10 and the cutting blade 14 is aligned

with the elastic element 11. When the estam-

  page and cutting 12 is lowered, the cutting blade 13 is effected

  kills a cut in the strip of thermoplastic material 9 where the strip 9 is in contact with the element

inserted and elastic 10 and it is therefore used to separate the receptacle

  tackle the rest of the strip 9. The second cutting blade 14 cuts in the molded part of the strip in

the area which is in contact with the inserted and elastic element

as 11, thus performing the cutting of a circular disc from the base of the receptacle, thereby defining the opening 4 which is in the base of the receptacle. Since the two cutting blades 13, 14 cut the portions of the strip which are supported by the inserted and elastic elements 10, 11, the step of stamping and of

  cutting can take place simultaneously at two tiered levels.

  This is practically impossible with the estam-

  classic pages in which a stamping and cutting step is performed against a hard or rigid abutment surface. The method described above which uses elastic abutment surfaces allows relatively tolerances

  between the positioning of the two stop surfaces.

It has been found that differences reaching several tenths of a millimeter always make it possible to obtain satisfactory stamping. However, the cutting edges 13 and 14 are preferably heated since this facilitates

the operation of the device.

  As can be seen in fig. 3, the bottom of the hollow

ment formed in the tool 7 is provided with an opening 15.

As can be seen in fig. 4, this opening 15 is connected to a pipe 16 in which a suitable flap 17 is mounted. The pipe 16 is connected to a source of vacuum or partial vacuum, such as a vacuum cleaner. During the vacuum molding step described above, the flap 17 is kept closed. Because a certain amount of air is present in the pipe 16 between the closed flap 7 and the recess in the mold, the part of the strip 9 is drawn down against the base of the recess of the mold 7 and it is not sucked through the opening 9 but retains a substantially planar configuration. It should be noted that this part of the base does not remain completely flat but usually forms a bulge 18 directed slightly downwards because this part of the strip 9 is not supported by a support surface during the step. molding. However, this is of little importance as, as will now be described, this part of the strip is removed and is not part of the receptacle

finally got it.

When the stamping step is finished, the flap 17 is open. The vacuum or partial vacuum is thus set

  communication with opening 15 and due to the differ-

  Between the pressure prevailing inside the recess and the mold 7 and the pressure prevailing in the pipe 16, the punched disc 18 is sucked into the pipe 16, beyond the flap 17, to reach a collecting device. appropriate. The molding method described above therefore makes it possible to obtain a receptacle formed integrally by means of a thermoplastic material, comprising a side wall, an upper flange facing outwards and a lower flange facing towards the interior. It will be understood that by using the method described above, we

  can produce receptacles with considerable precision

  maple, the upper and lower flanges being correctly centered and the central disc of the bottom being punched with precision. The receptacle can however be

produced quickly and at low cost.

  A disc 5, such as a disc intended to constitute a filter element and described with reference to FIGS. 1 and 2, can be easily connected to the receptacle manufactured in the manner described above. As shown in fig. 5, one can use a tool 19 having a circular part supporting a disc 5, the part of the tool 19 supporting the disc being heated. The tool can be moved so that the periphery of the disc 5 is brought into contact with the flange facing inward and formed at the bottom of the receptacle and, because the tool is heated, the disc 5 found thermally welded to the receptacle. As shown in fig. 6, it is desirable that the tool 19 can be provided initially with a sheet 29 of paper or the like to form the disc 5, this sheet

having dimensions greater than its final dimensions.

The tool 19, at the same time as the sheet 29 can then pass through a stamp 30 located above the tool 7, the stamp 30 and the tool 19 cooperating to provide a disc of desired dimensions. Tool 19 can also be used as a sorting and stacking element for

  receptacles after manufacture, if desired.

If we now refer to fig. 7 of the accompanying drawings, this represents another tool which can be

  used for implementing the method according to the invention.

The illustrated tool 7 comprises two recesses in which one can vacuum in vacuum elements of a strip 9 of a heated thermoplastic material. A cutting and stamping tool 12 is provided, comprising heated cutting edges 13, 13a corresponding to those described above, which cut in the region of the strip supported by elastic abutment surfaces. However, in the illustrated arrangement, the tool 12 is provided with two perforation elements 12a, 12b, each perforation element comprising a disc-shaped member provided with a series of heated points 22 directed downwards, suitable for being inserted into the material defining the base of the receptacle, while the receptacle is still in the mold. The base of the recess defined in the mold 7 is constituted by an elastic material 24. It will be understood that, when the tool shown in FIG. 7, perforations are formed in the base of the receptacles produced at the same time as the receptacles are cut from the rest of the strip 9. FIG. 8 represents a receptacle made by the tool illustrated in FIG. 7 and shows the perforations 20 formed in the base

of the receptacle.

It will be understood that the perforations 20 formed in the base of the receptacle can be formed against a support surface and therefore can therefore be formed by ultrasound. The perforation step can also be performed in a station separate from the molding station. Alternatively, the perforation tool can be located at the delivery station where the manufactured receptacles are removed from the mold and can therefore be combined with a stacking device instead of being combined with the stamping function such as

as illustrated in fig. 7.

  Fig. 9 shows another embodiment of a receptacle manufactured according to the invention, the receptacle being of generally rectangular configuration and comprising reinforcing or stiffening ribs 21 extending across its base surface. Advantageously, parts 23 of the base can be embossed in whole or in part during the manufacture of the receptacle, or even these parts can be perforated. In any case, the regions of the base located between the reinforcing elements 21 can be covered by a material permeable to gases or liquids. Fig. 10 shows another embodiment of a

  -receptacle manufactured according to the invention, the receptacle illus-

very intended to be used as a tea strainer.

  Note that two projections 25, 26 horizontal and sensitive

  completely rectangular are formed integrally with the side wall of the receptacle 1 and are sufficiently rigid so that the receptacle can be placed on a container such as a tea cup when used in

as a tea strainer.

It will be understood that the receptacle shown in FIG. can be used as an infuser. Thus, for example, the receptacle can be filled with an appropriate amount of a substance to be extracted, such as coffee, and one can then mount a leak-proof cover.

fluids, in the form of a suitable sheet

required, in position above the open upper mouth of the receptacle. Coffee can then be prepared by pouring boiling water through the liquid-permeable cover sheet, and therefore through the coffee contained inside the receptacle, the water

  infused leaving the receptacle by its permeable base.

Naturally, one can extract or infuse others

substances than coffee.

  Fig. it represents yet another receptacle,

  carried out by means of a method according to the invention, the reception

tackle 27 which is illustrated consisting of a pot intended to contain plants or plants. Four holes 28 are formed in the base of the receptacle. When the receptacle is used, that is to say when plants or plants grow in the receptacle, the receptacle is maintained

in an appropriate support.

  It will be noted that the invention has been described with reference to simple embodiments of the molding tool and

that the molding tools are provided with cooling means

classic dissement. Likewise, while the invention was

described with reference to tools comprising one or more

  tools can be designed with a large number of recesses. This is how we can envisage a molding machine with which we can produce for example 64 receptacles during a molding cycle of 4 seconds. This corresponds to an overall production rate of 960 receptacles per minute. It's easy to understand

  that this level of production makes it possible to produce receptacles

  keys in large series and at low prices.

  The receptacles can be made with a bulge

on their side wall to facilitate stacking.

It will be understood that the invention is not limited to the specific embodiments illustrated and that it can be modified in various ways without departing from the scope.

of application indicated in the appended claims.

It should be emphasized that a receptacle eye may have any suitable cross section, not only circular or rectangular, and that moreover the base surface of the receptacle need not be flat. The receptacles according to the present invention can be manufactured at such a low price that they can be

consider as disposable receptacles.

Claims (26)

1 - Method for manufacturing receptacles comprising the steps consisting in molding a strip (9) of thermoplastic material in a molding tool (7) or mold at a molding station so that the strip forms a receptacle key (1) comprising a lateral wall (la) impermeable to and cutting the receptacle formed from the rest of the strip by means of associated elements which can move relative to each other, characterized in that during or after the molding step the receptacle (1 ) is provided with a permeable or semi-base base part (5) permeable. 2 - Method according to claim 1, - characterized in that said receptacle (1) is molded from a heated strip (9) of a thermoplastic material which is made intermittently advance into the molding station. 3 - Method according to claim 1 or 2, character- se in that one or more molding tools (7, 7 ') are brought to an operating position at the molding station so that a receptacle (1) can be molded therein, and in that molding tools or forming (7, 7 ') which were previously at the molding station are moved simultaneously- to a delivery station so that receipts keys molded inside can be removed. 4 - Method according to any one of claims above, characterized in that the molding tool (7) comprises a recess in the tool. and in that it comprises means (15, 16, 17) for evacuating the hollow- so as to form the strip of material under vacuum. 5 - Method according to any one of claims 1 to 4, characterized in that said receptacle (1) is de- cut from the strip (9) by a cutting blade (13) cooperating with a surface (10) of elastic stop in the tool molding (7). 6 - Method according to claim 5, characterized in what the cutting blade (13) is processed. 7 - Method according to any one of claims previous, characterized in that it allows to form a receptacle (1) comprising a base forming an integral part grante, perforations (20) being formed in the base of the receptacle. 8 - Process according to claim 7, characterized in that the step of perforating the base is carried out in the molding tool (7). 9 - Method according to claim 8, characterized in that the step of perforating the base is carried out by means of heated spikes (22) cooperating with a surface elastic stop (24) forming part of the mold tool beam (7). - Method according to claim 9, characterized in that the perforation step is performed at the same time as the step of separating the molded receptacle (1) from the rest of the strip (9). 11 - Method according to claim 7 or 8, characterized in that the perforation step is performed ultrasoni- only against a rigid support surface. 12 - Method according to any one of claims 1 to 6, characterized in that the base of the receptacle is es- fully or partially buffered in the mold tool ge (7). 13 - Method according to claim 12, characterized in that the base of the receptacle is stamped at the same time as the receptacle and cut from the rest of the strip (9). 14 - Method according to claim 13, characterized in that the base of the receptacle is shaped by a flange cutting (14) cooperating with an elastic stop surface that (he) in the molding tool (7). 15 - Method according to claim 14, characterized in that the cutting edge (14) which stamps said base is heated. 16 - Method according to any one of claims 12 to 15, characterized in that the base of the recess of the molding tool (7) in which the receptacle (1) is formed is provided with an opening (15) and in that means are provided for connect the opening to a vacuum or partial vacuum source so that after stamping 24749g43 1 4 the base of the receptacle, the cut base is evacuated from the partial vacuum molding tool. 17 - Method according to claim 16, characterized in that a control valve (17) is provided between said opening (15) and the source of vacuum or partial vacuum. 18 - Method according to any one of claims 1 to 17, characterized in that the perforations (20) or or grooves (28) formed in the base of the receptacle are re- covered by a gas or liquid permeable element (5) helpers. 19 - Method according to claim 18, characterized in that the perforations (20) or openings (28) formed in the base are covered by a filter element. - Method according to claim 19, characterized in that the filter element is constituted by a filter paper. 21 - Method according to any one of claims 18 to 20, characterized in that the element permeable to gases or liquids is fixed to the receptacle (1) by welding thermal. 22 - Method according to any one of claims 18 to 20, characterized in that the gas permeable element or to liquids is fixed to the receptacle (1) by gluing. - Method according to any one of the claims previous, characterized in that it includes the steps consisting in manufacturing a receptacle (1) provided with a bom- outwardly directed peripheral unit located some distance from the upper end of the receptacle to facilitate stacking. 24 - Method according to any one of claims above, characterized in that it comprises the step ad- additional consisting of providing the receptacle (1) with projections (25, 26) rigid, substantially horizontal and protruding outward. 25 - Method according to any one of claims previous, characterized in that it comprises the step sistant to provide a receptacle (1) of reinforcing or stiffening members (21) extending along the base of the receptacle. 26 - Method according to any one of claims previous, characterized in that the receptacle (1) is provided with a peripheral collar (2) extending radially outwardly at the top of said receptacle. 27 Receptacle, characterized in that it comprises a side wall (la) substantially liquid tight and a permeable or semi-permeable base part. 28 - Receptacle according to claim 27, characterized in that its permeable or semi-permeable base part is substantially planar. 29 - receptacle according to claim 27, characterized in that the side wall (la) and the base part are prepared from a thermo-plastic sheet by molding hot lage. - Receptacle according to claim 29, characterized in that the base part is provided with one or more openings (28) or is perforated (at 20) at least in one certain measure. 31 - receptacle according to claim 27 or 28, ca- characterized in that the base part is made of a prefabricated sheet (5), preferably gas permeable or liquids, suitable for being fixed at the lower limit re (3) of the side wall (la). 32 - Receptacle according to any one of the claims tions 27 to 31, characterized in that the lateral limit (the) upper is connected to a flange (2) extending in the periphery.