METHOD FOR MANUFACTURING THREE-DIMENSIONAL ARTICLES HAVING A FLEXIBLE WALL

Abstract

Method for manufacturing three-dimensional articles with a flexible wall, by means of a mould (1-2) and a counter-mould (3) between which pieces (4) are arranged that will form the article to be obtained. Between the pieces (4), the mould (1-2) and counter-mould (3) a conduit network (7) and cavities (6) are delimited into which, through first points (8), a plastic material is injected in a melted condition, whereas through one or more second points (9) said conduit network is connected to a vacuum network.

Claims

1. Method for manufacturing three-dimensional articles, comprising a mould and a counter-mould between which a space is delimited having the shape and volume of the article to be obtained, said article consisting of laminar pieces arranged between the mould and the counter-mould, and bound by a plastic material being injected through a conduit network delimited between the mould, counter-mould and laminar pieces, wherein said conduit network is connected through at least one first point to the means for injecting the plastic material in a liquid state or without curing, wherein through at least one second point, being distant from the first point, said channel network is connected to a vacuum source, and wherein the pieces forming the mould are provided of an outer coating, based on a material having high deformation capacity, the edges of which rest against each other when attaching said pieces.

2. Method according to claim 1, wherein the conduit network is connected, through said second point or points, to an auxiliary vacuum chamber formed onto the mould which, in turn, is connected to a vacuum source.

3. Method for manufacturing three-dimensional articles according to claim 1, by means of a mould and a counter-mould comprising, at the mutual support surfaces thereof, recesses facing each other which delimit, upon attaching said mould and counter-mould, tight chambers that can be connected to a vacuum source, wherein the conduit network is connected through second point or points to the tight chamber or chambers delimited between the mould and counter-mould, the tight chambers of which are connected, in turn, to a vacuum source.

4. Method according to claim 3, wherein the conduit network is provided, at the second points, with filters being air permeable and impermeable to the plastic injected therein.

5. Method according to claim 4, wherein the injected plastic material undergoes, once inside the conduit network, a reaction causing expansion thereof.

6. Method according to claim 5, wherein the mould and/or counter-mould are provided, along the perimeter delimiting the areas occupied by the pieces forming the article to be obtained, with tight gaskets.

7. Method according to claim 6, wherein fastening of the pieces forming the article to be obtained on the mould is performed by means of vacuum, created through the conduits which open into the mould surface, in the areas that said pieces will occupy, and start from the chamber through which vacuum is created in the conduit network.

8. Method according to claim 7, wherein the laminar pieces have oblique cuts facing each other, between which angled channels are delimited, the vertex of which is directed towards the outer surface of the article to be obtained.

9. (canceled)

10. Method according to claim 1, wherein on the facing surfaces of the pieces forming the mould, and around the areas that the pieces forming the article to be obtained will occupy, a coating is applied of a substance having high deformation capacity, such as silicone.

11. Method according to claim 10, wherein on the surfaces of the mould onto which the pieces of the article to be obtained are arranged, a substance is applied, such as silicone, acting as a slip agent between said surfaces and pieces.

12. Method according to claim 11, wherein the pieces forming the article to be obtained are provided with an outer coating based on a material having high adherence capacity with respect to the injected plastic material.

13. An article of manufacture comprising a mould and a counter-mould between which a space is delimited having the shape and volume of the article to be obtained, said article consisting of laminar pieces arranged between the mould and the counter-mould, and bound by a plastic material being injected through a conduit network delimited between the mould, counter-mould and laminar pieces, wherein said conduit network is connected through at least one first point to the means for injecting the plastic material in a liquid state or without curing, wherein through at least one second point, being distant from the first point, said channel network is connected to a vacuum source, and wherein the pieces forming the mould are provided of an outer coating, based on a material having high deformation capacity, the edges of which rest against each other when said pieces are attached.

14. The article of manufacture according to claim 13, wherein the conduit network is connected, through said second point or points, to an auxiliary vacuum chamber formed onto the mould which, in turn, is connected to a vacuum source.

15. The article of manufacture according to claim 13, wherein the injected plastic material undergoes, once inside the conduit network, a reaction causing expansion thereof.

16. The article of manufacture according to claim 13, wherein the mould and/or counter-mould are provided, along the perimeter delimiting the areas occupied by the pieces forming the article to be obtained, with tight gaskets.

17. The article of manufacture according to claim 13, wherein the laminar pieces have oblique cuts facing each other, between which angled channels are delimited, the vertex of which is directed towards the outer surface of the article to be obtained.

18. The article of manufacture according to claim 13, wherein on the facing surfaces of the pieces forming the mould, and around the areas that the pieces forming the article to be obtained will occupy, a coating is applied of a substance having high deformation capacity, such as silicone.

19. The article of manufacture according to claim 13, wherein on the surfaces of the mould onto which the pieces of the article to be obtained are arranged, a substance is applied, such as silicone, acting as a slip agent between said surfaces and pieces.

20. The article of manufacture according to claim 13, wherein the pieces forming the article to be obtained are provided with an outer coating based on a material having high adherence capacity with respect to the injected plastic material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The attached drawings represent a non-limiting exemplary embodiment, wherein:

[0028] FIG. 1 is a perspective view of a mould and counter-mould for obtaining a neoprene suit, according to the method indicated in the state of the art.

[0029] FIG. 2 is a schematic section of mould and counter-mould for manufacturing shoes with the method of the invention.

[0030] FIG. 3 is a partial section of the mould from FIG. 1, taken according to the cutting line III-III.

[0031] FIG. 4 is a similar section to that from FIG. 3, showing an execution variant.

[0032] FIG. 5 shows a sectional profile of facing edges of laminar pieces that will form the article to be obtained.

[0033] FIG. 6 is a similar section to that of FIG. 5, showing a possible fastening system for the laminar pieces on the mould.

[0034] FIG. 7 shows a perspective of mould consisting of three pieces provided with an outer sealing coating.

[0035] FIG. 8 shows a section of a peripheral sealing system of the pieces forming the article to be obtained, during the injection step.

DETAILED DESCRIPTION OF AN EMBODIMENT

[0036] FIG. 1 shows a mould that can be made up of two pieces (1 and 2) or more, and a counter-mould (3) that can be also made up of one or more pieces. Between pieces (1 and 2) of the mould and the counter-mould (3) there is a space being delimited the shape and volume of which corresponds to that of the article to be obtained. In this case it is a neoprene suit.

[0037] According to the method described in PCT/ES2012/070139, the article to be obtained, in this case the neoprene suit, comprises laminar pieces (4) being arranged on the inner surface of the mould (1-2) and will have a thickness being approximately the same as the distance between the mould and the counter-mould. Between the pieces (4) and the surface of the mould (1-2) channels (5) are delimited being enclosed by the counter-mould (3), forming a conduit network being interconnected to each other, through which a plastic material will be injected in a melted state, which upon solidification thereof will be used as a means for attaching the pieces (4).

[0038] In order to make the melted plastic material flow easily along the conduit network, according to the present invention, said conduit network is connected, through points being distant to those for injecting the melted plastic material, to a vacuum source so as to create in the conduit network a low pressure that guarantees the melted plastic to flow from the injection point or points to the end of the conduit network.

[0039] As it has been already indicated, flow of the plastic material being injected through the conduit network can be improved by using a material that, when it is injected therein, reacts producing certain expansion thereof.

[0040] FIG. 2 shows a mould, also consisting of two pieces (1 y 2) and a counter-mould (3), for obtaining a shoe. The counter-mould (3) adopts the shape of a shoe tree. As in the previous case, on the inner surface of the piece (1) of the mould, laminar pieces (4) are arranged being of a flexible nature, configuring the shoe upper and the thickness of which corresponds approximately to the distance between the facing surfaces of said pieces (1) and the counter-mould (3). The mould is closed by means of the piece (2), delimiting with the counter-mould (3) a chamber (6), the volume of which may correspond to that of the shoe sole and heel.

[0041] Also, as in the previous case, between the laminar pieces (4) and the facing surfaces of the mould (1-2) and counter-mould (3) a conduit network (7) is formed through which melted plastic will be injected.

[0042] According to the invention the injection of melted plastic material is performed in the conduit network (7) through one or more first points (8), whereas through one or second points (9) said conduit network is connected to a vacuum source, with the second points (9) being distant from the first points (8) and preferably situated at the end of the conduit network, considering the first points (8) as the beginning or start of said network. In the first injection point or points (8) a check valve is arranged for preventing the injected plastic to come out, once injection is finished.

[0043] With this system, it is guaranteed that the melted plastic being injected through the first points (8) runs along the whole conduit network, until reaching the second points (9) situated at the end of said conduit network.

[0044] The mould of FIG. 1 can be as that described in PCT/ES2014/070672, wherein the pieces (1-2) making up the mould, FIG. 3, are provided at the attaching surfaces thereof with recesses (11 and 12) facing each other, which form a tight chamber (13) which is connected to a vacuum source, so as to secure the attachment and closure between pieces (1 and 2) of the mould. Applying the method of the invention, the conduit network (5) may be connected to the vacuum source through the tight chambers (13). For that purpose, as it is shown in FIG. 3, the conduit network (5) is connected via second points (14) to the tight chamber or chambers (13) which in turn is connected to a vacuum source, for example through the valves (15). Between the pieces (10-11) there can be gaskets (16) arranged for tightness of the tight chambers (13).

[0045] In case the conduit network (5) requires, due to the length thereof, several second points (14) through which the vacuum is performed, these second points may open into at least an auxiliary vacuum chamber (17), FIG. 4, provided with a connection (18) to a vacuum source. Thus, by means of a single connection (18) to a vacuum source the required low pressure may be transmitted to the conduit network through several second points (14). The pieces (10-11) making up the mould may correspond to the constitution being described in reference to FIG. 3.

[0046] When the conduit network opens into one or more tight (13) or vacuum (17) chambers, through which vacuum is performed in the conduit network, filters can be arranged at said mouths that, by allowing the air to pass through, prevent the plastic injected through the conduit network from entering into the chambers. Preferably, the laminar pieces (4-4) forming the product to be obtained will be cut with oblique edges (19-20) facing each other, as it is shown in FIG. 5, such that angle-sectioned channels (21) are formed between them, with the vertex (22) directed towards the outer surface of the product or garment to be obtained.

[0047] Fastening of the laminar pieces (4-4) on the surface of the pieces (1-2) forming the mould can be guaranteed by means of ribs projecting from said surfaces and being accommodated into channels (23-24) made on the facing surfaces of the laminar pieces (4-4), FIG. 6.

[0048] Also fastening of the pieces forming the product to be obtained on the mould may be attained by means of a vacuum effect, created through the conduits opening onto the mould surface, in the areas that said pieces will occupy, and starting from the tight (13) or vacuum (17) chambers through which vacuum is created in the conduit network.

[0049] As it can be seen in FIG. 4, the pieces (1 and 2) making up an outer coating (25) based on a material having high deformation capacity, such as silicone, the edges (26) of which rest on and are pressed against each other, upon attaching the pieces (1 and 2), providing for a mould closure being tight with respect to the outer one.

[0050] This arrangement can be better appreciated in FIG. 7, representing a mould consisting of two pieces (27-28), and a counter-mould (29) which are provided with an outer coating (25), similar to that of FIG. 4, by way of a lining, based on a material having high deformation capacity, slightly projecting from the facing surfaces of the pieces (27-28-29). By attaching and adjusting to each other the pieces of the mould and counter-mould, the edges of the coating (25) rest against each other and, thanks to the deformation capacity thereof, they form an outer tight closure for the mould assembly.

[0051] When the pieces (4-4) forming the article to be obtained are made of a material having low adherence capacity for the injected plastic, said pieces can be provided with an outer laminar coating (30), FIG. 8, for example based on a fabric which, as well as providing a good adherence for the plastic (31) being injected, can be penetrated by said plastic along the width of a peripheral strip (32) that will also act as a closure so as to prevent said plastic material from penetrating deeper into the outer laminar coating (30) and as gripping or anchoring means for the laminar coating.