METHOD FOR MANUFACTURING A PRODUCT PROVIDED WITH A CAVITY, PRODUCT AND SYSTEM FOR THE MANUFACTURE THEREOF

Abstract

The product manufactured according to the method is waterproof and provided with a cavity, such as a glove, shoe, or a backpack. Initially, a structure is made in the shape of the product by stitching portions of a laminated material attached together by corresponding seams. The stitched structure is then turned inside out and a thermally-curable silicone compound material, in uncured liquid state, is applied on the seams. The structure with applications is then simultaneously subjected to heating with a curing temperature of the material, and to a vacuum operation with pumping means that suck in air from outside the structure with applications into the structure and extract it outside. The invention also relates to a system for manufacturing according to the method.

Claims

1. A method for manufacturing a product that is waterproof and provided with a cavity, such as a glove, a shoe, a sports shoe, or a backpack, characterised in that first a structure is made with the shape and outer surface of the product, provided with a cavity, stitching portions of laminated material such as laminated natural or synthetic leather, and/or a laminated material based on leather, and/or a laminated textile material, and/or a laminated substrate, attached together by corresponding seams and then the following steps are carried out: a) turning the structure inside out and applying a thermally-curable silicone compound material, in uncured liquid state, on the seams, including the stitches of the seams and the edges of the portions that form the seams, obtaining a structure with applications; b) subjecting the structure with applications of the silicone compound material obtained in step a) to heating at a curing temperature of said material, c) simultaneously to step b), and by means of pumping means, performing a vacuum by sucking the air from outside the structure with applications of the silicone compound material obtained in step a) into the structure through the seams thereof, and from there extracting said air outside.

2. The method according to claim 1, characterised in that the heating of step b) occurs at a temperature comprised between 115° C. and 150° C. for a period of between 2 and 30 min.

3. The method according to claim 1, characterised in that the application on the seams of the thermally-curable silicone compound material, in uncured liquid state, of step a) is performed with a brush or a paintbrush.

4. The method according to claim 1, characterised in that at least steps b) and c) are carried out in a chamber or oven inside of which the structure with applications obtained in step a) is placed, the air that is sucked in from outside the structure being the air present inside the chamber or oven, and in that the air sucked into the structure in step c) is extracted from inside the structure to the outside of the chamber or oven by the pumping means.

5. The method according to claim 4, characterised in that the application on the seams of the thermally-curable silicone compound material, in uncured liquid state of step a) is performed inside the chamber or oven which steps b) and c) are carried out.

6. The method according to claim 4, characterised in that the application on the seams of the thermally-curable silicone compound material, in uncured liquid state of step a) is performed outside the chamber or oven in which steps b) and c) are carried out.

7. The method according to claim 1, characterised in that the application on the seams of the thermally-curable silicone compound material, in uncured liquid state of step a) is performed with the structure turned inside out tightly fitted on a hollow inner mould or skeleton the outer surface of which reproduces the inner shape of the structure of the product, the inner mould or skeleton being provided with a plurality of vacuum openings which communicate the outside of the inner mould or skeleton with the inner cavity thereof.

8. The method according to claim 1, characterised in that steps b) and c) are performed with the structure turned inside out with applications obtained in step a) fitted on a hollow inner mould or skeleton the outer surface of which reproduces the inner shape of the structure of the product, the inner mould or skeleton being provided with a plurality of vacuum openings that communicate the outside of the inner mould or skeleton with the inner cavity thereof, the vacuum openings being crossed by air from outside the structure that is sucked into the structure in step c) and from there extracted outside.

9. The method according to claim 7, characterised in that the inner mould or skeleton on which the structure is fitted turned inside out for the application on the seams of the thermally-curable silicone compound material, in uncured liquid state, of step a) is the same inner mould or skeleton on which the structure is fitted when steps b) and c) are performed.

10. The method according to claim 7, characterised in that the vacuum openings that communicate the outside of the inner mould or skeleton with the inner cavity thereof are configured as through holes, as meshes of a net from which the inner mould or skeleton is made, or as elongated slits.

11. The method according to claim 7, characterised in that the hollow inner mould or skeleton is made of metal or a plastic material that is dimensionally stable at the curing temperature of the thermally-curable silicone compound material that is applied in uncured liquid state in step a).

12. The method according to claim 1, characterised in that the portions of laminated material are portions of natural or synthetic leather attached to a plastic sheet or membrane, and/or portions of reconstituted leather or bicast leather attached to a plastic sheet or membrane.

13. The method according to claim 1, characterised in that the laminated textile material and/or the laminated substrate are woven or non-woven materials comprising natural fibres and/or synthetic fibres, attached to a plastic sheet or membrane.

14. A product that is waterproof and provided with a cavity, such as a glove, a shoe, a sports shoe or a backpack, of laminated material such as laminated natural or synthetic leather, and/or a laminated material based on leather, and/or a laminated textile material, and/or a laminated substrate, characterised in that it is obtainable by the method according to claim 1.

15. The product that is waterproof and provided with a cavity, such as a glove, a shoe, a sports shoe or a backpack, of laminated material such as laminated natural or synthetic leather, and/or a laminated material based on leather, and/or a laminated textile material, and/or a laminated substrate, according to claim 14, characterised in that the holes of the stitches of the seams of the product are partially or completely filled with a thermally-cured silicone compound, with a filling depth of at least 30% of the sum of the thicknesses of the portions of laminated material attached at the seams.

16. A system for manufacturing a product that is waterproof and provided with a cavity, such as a glove, a shoe, a sports shoe or backpack, wherein the product comprises a structure with the shape and outer surface of the product, provided with a cavity, the structure being made up of portions of laminated material such as laminated natural or synthetic leather, and/or a laminated material based on leather, and/or a laminated textile material, and/or a laminated substrate, stitched and attached together by corresponding seams, characterised in that it comprises: at least one hollow inner mould or skeleton the outer surface of which reproduces the inner shape of the structure of the product, the inner mould or skeleton being provided with a plurality of vacuum openings that communicate the outside of the inner mould or skeleton with the cavity thereof; a chamber or an oven with room to arrange inside the at least one hollow inner mould or skeleton, with heating means, and pumping means to create the vacuum inside the inner mould or skeleton, capable of being activated when the at least one hollow inner mould or skeleton is arranged inside the chamber or oven, sucking the air from outside the inner mould or skeleton into the cavity thereof through the vacuum openings and extracting said sucked air out of the cavity and the chamber or oven.

17. The system for manufacturing a product that is waterproof and provided with a cavity, such as a glove, a shoe, a sports shoe or a backpack, according to claim 16, characterised in that the vacuum openings that communicate the outside of the inner mould or skeleton with the cavity thereof are configured as through holes, as meshes of a net from which the inner mould or skeleton is made, or as elongated slits.

18. The system for manufacturing a product that is waterproof and provided with a cavity, such as a glove, a shoe, a sports shoe or a backpack, according to claim 16, characterised in that the hollow inner mould or skeleton is metallic or made of a plastic material that is dimensionally stable at a temperature comprised between 115° C. and 150° C.

19. The system for manufacturing a product that is waterproof and provided with a cavity, such as a glove, a shoe, a sports shoe or a backpack, according to claim 16, characterised in that it comprises a plurality of hollow inner moulds or skeletons arranged on a conveyor belt, band or strap in which each hollow inner mould or skeleton is connected to respective pumping means suitable for creating a vacuum inside the respective inner mould or skeleton, and in that the chamber or oven extends longitudinally in the direction of advance of the conveyor belt, band or strap, and is configured with two ends provided with means to enable the inlet and outlet of a group of the plurality of inner moulds or skeletons to/from the chamber or oven.

20. The system for manufacturing a product that is waterproof and provided with a cavity, such as a glove, a shoe, a sports shoe or a backpack, according to claim 16, characterised in that the portions of laminated material are portions of natural or synthetic leather attached to a plastic sheet or membrane, and/or portions of reconstituted leather or bicast leather attached to a plastic sheet or membrane.

21. The system for manufacturing a product that is waterproof and provided with a cavity, such as a glove, a shoe, a sports shoe or a backpack, according to claim 16, characterised in that the laminated textile material and/or the laminated substrate are woven or non-woven materials comprising natural fibres and/or synthetic fibres, attached to a plastic sheet or membrane.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The attached drawings illustrate, by way of non-limiting example, portions of the stitched structure from which a product provided with a cavity, such as a glove, is manufactured according to the method object of the invention, as well as two embodiments of the system for manufacturing the product. In said drawings:

[0036] FIG. 1 schematically shows a cross section of two portions of laminated material, such as laminated leather, attached by stitching, of the stitched structure, the direction of the depth of a stitch of the attachment seam between said portions being marked with a dashed line;

[0037] FIG. 2 is an enlarged view of the seam of FIG. 1 showing the applications of thermally-curable silicone in liquid state at the ends of the stitch and at the ends of the laminated material portions of the seam;

[0038] FIG. 3 is an enlarged view of the seam of FIG. 1 when the method object of the invention has finished, showing the cured silicone inside the hole of the stitch;

[0039] FIG. 4 schematically shows a first embodiment of the system in which the step of sealing the seams of the stitched structure is carried out to manufacture the product or article, in this case a glove, according to the method object of the invention;

[0040] FIG. 5 shows a hollow inner mould or skeleton formed by a net provided with meshes that cross it, as an alternative to the inner mould or skeleton represented in FIG. 4, with some of the pumping means;

[0041] FIG. 6 shows a third embodiment of the hollow inner mould or skeleton provided with slits for the passage of air therethrough, with some of the pumping means;

[0042] FIG. 7 schematically shows a second embodiment of the system in which the step of sealing the seams of the stiched structure is carried out to manufacture the product according to the method object of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[0043] FIG. 1 shows a cross section of two portions 2 of laminated material, such as laminated leather or a laminated textile material, attached by stitching, which form part of a stitched structure for manufacturing a product or article provided with a cavity, such as a glove, a shoe, a sports shoe or a backpack.

[0044] Laminated leather is a tanned leather to which a plastic sheet or membrane 22 is adhered to the grain of the leather 21 (the upper portion) with heat and pressure, achieving uniformity on the entire surface of the leather. Similarly, a laminated textile material is that formed by a fabric (which would be comparable to the grain of the leather 21) to which a plastic sheet or membrane 22 adheres, on the non-visible face thereof. Laminated leather and laminated textile material are waterproof materials, and in many cases they are also windproof and breathable (permeable to water vapour), so it is very advantageous to manufacture products or articles from them such as gloves, shoes, sports shoes (for example, for sports practice), boots or backpacks so that these products also exhibit these properties.

[0045] The portions 2 are intended to be made of any one of the following laminated materials: laminated leathers or leather-based laminates, including laminated natural leathers, laminated synthetic leathers, and other types of laminated materials similar to laminated leather, such as bicast leather or reconstituted leather materials; laminated textile materials and laminated substrates, the structure that is attached to the plastic sheet or membrane being able to be formed by natural or synthetic fibres, woven or non-woven, and the laminated substrates being able to further exhibit a synthetic matrix on which fibres of synthetic natural origin are arranged.

[0046] To carry out the manufacture of these products, first a structure 10 is made with the shape of the product by stitching portions 2 of laminated material attached together by corresponding seams 3, that is, joining the portions 2, facing them or partially overlapping them and stitching them together so that they stay together.

[0047] This structure 10 is the part of the product that will remain on the outside once finished, with the shape and surface thereof, that is, as an outer structure of the glove, shoe, or backpack that is manufactured. When joining the portions 2 by means of seams 3, it must be taken into account that when passing the thread that holds the portions 2 together, the needle or tool creates stitches 4 in the portions 2 of laminated material. These stitches 4 are the holes through which the thread passes but which at the same time represent a path for the inlet of water, wind and water vapour, so if they are not properly sealed, the product being manufactured will no longer be waterproof. The same happens with the edges 31 of the facing or overlapping portions 2 that form the seams 3, since it is also necessary to seal them.

[0048] A dashed line in FIG. 1 marks the direction in which the depth 40 of a stitch 4 of the attachment seam 3 between said portions 2 extends. The depth 40 of the stitch 4 in the case represented is the sum of the thicknesses of the two portions 2 of laminated material joined at the seam 3.

[0049] In order to carry out the correct sealing of the stitches 4 and of the edges 31 of the seams 3, the stitched structure 10 with the shape of the product and formed by a plurality of portions 2 attached by seams, is turned inside out. FIG. 4 represents the structure 10 with a dashed line for greater clarity. Thus, if it is a stitched structure 10 of a glove, the inner surface of said structure 10 will be exposed to the outside and the same with the rest of the stitched structures 10 of shoes, sports shoes, boots and backpacks, leaving on the outside the surface that corresponds to the inner surface of the stitched structure 10 that forms part of the product in the normal use thereof by a user.

[0050] The portion of structure 10 shown in FIGS. 1 to 3 is not represented turned inside out, but must be turned so that the stitches 4 and the edges 31 are easily accessible to apply a thermally-curable silicone compound material, in uncured liquid state 5, on the seam 3 (including the stitches 4 and the edges 31). The application can be made with a brush, paintbrush or with a spray gun. FIG. 2 shows the stitched structure with the applications of said thermally-curable silicone compound material, observing how said material is placed at the two ends of the stitch 4, which are the holes created in the portions 2 of laminated material when the needle and the thread of the seam 3 have passed.

[0051] To apply the thermally-curable silicone compound material, in uncured liquid state 5, on the seams 3, the structure 10 turned inside out is fitted tightly on a hollow inner mould or skeleton 7 the outer surface of which reproduces the inner shape of the product (particularly, the inner shape of the structure 10), such as those shown in FIGS. 4 to 6. The hollow inner mould or skeleton 7 fills the inside of the turned structure 10 and acts as a support of the same to apply the material on the seams 3 and also plays an important role in the following steps of the method that are described below.

[0052] The hollow inner mould or skeleton 7, which can be metallic or made of a plastic material resistant to the curing temperature of the silicone compound material, is provided with vacuum openings, configured as through holes 71 in FIG. 4. According to the option in FIG. 5, the inner mould or skeleton 7 is formed by a net of resistant threads or wires that, by interlocking, form meshes 72 (vacuum openings) with each other. By contrast, in FIG. 6, the hollow inner mould or skeleton 7 is formed by a body built with a 3D printer in which the vacuum openings are configured as slits 73. The vacuum openings communicate the outside of the hollow inner mould or skeleton 7 with the cavity thereof.

[0053] After applying the thermally-curable silicone compound material, in uncured liquid state 5, the structure 10 is simultaneously subjected to a heating operation at a curing temperature of said silicone compound material and to a vacuum operation. The vacuum operation consists of sucking the air from outside the structure 10 into the structure 10 by means of pumping means 9 and subsequently extracting it from the inside out, as shown in FIG. 4 with thick grey arrows. The structure 10 with applications is fitted on the inner mould or skeleton 7, provided with through holes 71, meshes 72, or slits 73, which is in turn arranged inside the chamber or oven 8 provided with heating means 81 and complemented with pumping means 9 to create the vacuum inside the inner mould or skeleton 7. The air extracted from inside the chamber or oven 8 passes through the through holes 71, meshes 72 or slits 73 to reach the cavity of the mould 7 and be expelled to the outside, out of the chamber or oven 8. Due to the fact that the seams 3 with applications of the silicone compound material of the structure 10 turned inside out are on one of the multiple vacuum openings of the inner mould or skeleton 7, when the vacuum is generated and the air is sucked into the structure 10, said silicone compound material in uncured liquid state 5 will be attracted penetrating into the holes of the stitches 4 and the spaces between the portions 2 joined by a seam 3.

[0054] FIG. 6, unlike FIG. 5, schematically represents (with a dashed line) the structure 10 tightly fitted on the inner mould or skeleton 7. This tightness is also seen in the lower portion, wherein the wrist portion of the glove is tightened around a cylindrical support on which the mould 7 is fixedly placed and which is provided with suction ports 91 that are part of the pumping means 9 for sucking the air in order to create the vacuum inside the mould 7 and the structure 10 arranged above.

[0055] What is achieved with the simultaneous heating and vacuum operations is that as the silicone compound material, initially in uncured liquid state 5, cures, becoming a silicone gel that is soft and flexible but very dimensionally stable with temperature, the silicone compound material enters and penetrates the holes of the stitches 4 of the seams 3 by the vacuum created, by which the silicone compound material is pushed by the air outside the stitched structure into the holes of the stitches 4. By creating the vacuum in the chamber or oven 8, in which the structure 10 with applications is located, air is extracted from inside this structure 10 with applications; in fact, air is extracted from inside the inner mould 7 which causes the curable silicone compound, in uncured liquid state 5, to enter and penetrate the holes of the stitches 4 of the seams 3.

[0056] With the pumping means 9, the air from the chamber or oven 8 that is outside the structure 10 of the product is sucked in and directed towards the cavity of the hollow inner mould or skeleton 7. The through holes 71, the meshes 72 or the slits 73 of the hollow inner mould 7 lead the air from inside the chamber or oven 8 into the inner mould 7 and from there it is extracted out of the oven 8 or chamber, so that the liquid silicone compound is initially introduced, by effect of the vacuum created, through the stitches 4 and spaces between the meeting points of the laminated portions 2.

[0057] The curing temperature and time will depend on the features of the thermally-curable silicone compound. For example, there are silicone compound that cure at 150° C. in 30 minutes and others that when cured at 150° C., do so in just 10 minutes. In most cases, the temperature in the chamber or oven 8 will be comprised between 115 and 150° C. and the curing will take between 2 and 30 min.

[0058] Once the silicone compound is fully cured by heating to the curing or crosslinking temperature, the orifices or holes of the stitches 4 are filled with a silicone gel 6 that is soft and flexible, but very dimensionally stable as mentioned above. The silicone gel 6 has penetrated at least to a depth from the beginning of the hole equivalent to 30% of the total depth of the hole (depth is the total thickness that crosses the stitch 4) when a vacuum is created. Thus, FIG. 3 shows how the hole of the stitch 4 has been plugged at both ends by the silicone gel 6, being perfectly sealed and also the edge 31 of the seam 3.

[0059] In this way, the structure 10 of stitched portions 2 is already entirely a waterproof structure, since the seams 3 have been perfectly sealed with the silicone gel 6. To finish making the product, the structure 10 will be removed from the inner mould or skeleton 7, it will be turned the right way round to put the structure of stitched portions with the sealed seams 3 the right way round and the finishing operations that are required will be carried out, such as putting a soft inner lining, a rubber or closure on the wrist portion, etc.

[0060] FIGS. 4 and 7 represent two embodiments of a system for carrying out the method described above, that is, for manufacturing a product provided with a cavity such as a glove, a shoe, a sports shoe or a backpack, wherein said product is waterproof, and optionally also windproof and breathable, starting from a structure 10 of portions 2 of laminated material such as laminated leather or similar (laminated synthetic leather, laminated reconstituted leather, etc.), of laminated textile material or of a laminated substrate, stitched together.

[0061] The system comprises one or more hollow inner moulds or skeletons 7 as those explained above, provided with through holes 71 or meshes 72 that cross it and communicate the outside of the hollow inner mould or skeleton 7 with the cavity thereof; pumping means 9 to create the vacuum inside each inner mould or skeleton 7; and a chamber or an oven 8 with room to arrange inside one or more hollow inner moulds or skeletons 7, the oven 8 having heating means 81 to reach the curing temperature of the silicone compound material initially in uncured liquid state 5.

[0062] FIG. 7 shows that the system comprises a plurality of hollow inner moulds or skeletons 7 arranged on a conveyor belt, band or strap 11 in which each hollow inner mould or skeleton 7 is connected to respective pumping means 9 for creating a vacuum inside the respective inner mould or skeleton 7. The chamber or oven 8 extends longitudinally in the direction of advance of the conveyor belt, band or strap 11 and is configured with two ends provided with means to enable the inlet and outlet of a group of the plurality of inner moulds or skeletons 7 to/from the chamber or oven 8. The pumping means 9 are activated to create the vacuum when the structures 10 turned inside out and with the applications of the silicone compound material initially in uncured liquid state 5 enter the chamber or oven 8, the heating means 81 being in operation. At the outlet of the oven 8, the seams 3 are already sealed with the silicone gel 6, plugging the stitches 4 and the edges 31 of the seams 3.