Dual chamber for absorption of a pressure increase

Abstract

The invention relates to a dual chamber (1) for absorption of a heterogeneous increase in pressure following an impact or a step, comprising a textile outer chamber and an inflatable inner chamber, wherein the textile outer chamber has an upper membrane (2) and a lower membrane (3) which are connected to one another by a lateral membrane (4) and by a plurality of partitions (5), which are preferably sewn together, the partitions (5) being positioned such that the textile outer chamber is forced to assume an angular shape during the inflation of the inner chamber.

Description

Double enclosure for absorption of increased pressure

[0001] The present invention relates to the field of absorbing an increase in pressure, in particular the field of cushioning a shock or a step. The field of the invention covers both the problems of shock absorption, protection of people or fragile objects, or even the comfort and performance associated with the cushioning properties of a shoe sole, in particular a sports shoe.

[0002] While it is known to use an air cushion to cushion a shock or absorb an increase in pressure, known technologies have notable drawbacks that limit their use.

[0003] First, an inflatable structure tends to take a shape that distributes the internal pressure as evenly as possible, which limits the shapes that known structures can take. Shapes that include angles are prohibited. These shapes are not compatible with all applications and limit the possibilities for distributing the absorption of an increase in pressure that would be heterogeneous.

[0004] Furthermore, known structures tend to wear out and lose efficiency as the pressure in the air chamber designed to absorb the increased pressure decreases, which occurs naturally over time and under stress.

[0005] The present invention makes it possible to resolve these shortcomings. Indeed, by constraining the inflation of a bladder by a second textile envelope which can be semi-rigid or even rigid in places, and comprising a network of internal partitions, it is possible to obtain a structure capable of taking irregular shapes and presenting angles. In addition, an asymmetrical arrangement of the partitions makes it possible to obtain a variable absorption response to the force applied to the double enclosure, and thus to allow a finer heterogeneous response.

[0006] Thus, the subject of the invention is a double enclosure for absorbing a heterogeneous increase in pressure following a shock or a step comprising a textile outer enclosure and an inflatable inner enclosure, in which the textile outer enclosure has an upper membrane and a lower membrane connected to each other by a lateral membrane and by a plurality of partitions, preferably sewn together, the partitions being positioned so that the textile outer enclosure is forced to take an angular shape when the inner enclosure inflates.

[0007] The external textile enclosure is not necessarily homogeneous and may include reinforcements, in particular reinforcements made of rigid or semi-rigid materials, which can limit wear of the external enclosure in areas that will be subject to heavy use. In addition, the presence of rigid or semi-rigid reinforcements can make it possible to modify the shape of the structure once inflated and to refine the response to the increase in pressure of the double enclosure. In addition, the use of a composite-type technical textile for such rigid or semi-rigid reinforcements makes it possible to choose directions of heterogeneous mechanical resistance in order to provide a shape or function to the object when it is inflated.

[0008] The inflatable inner enclosure is preferably made of a single deformable material which may or may not be elastic. The inner enclosure will advantageously have sufficient thickness to avoid any risk of leakage or puncture, the thickness in question depending on the material used. In addition, the use of an elastic material for the inflatable inner enclosure allows it to expand to fill volume gaps with the outer enclosure and thus ensure a shape match between the inner and outer enclosures.

[0009] This minimum thickness guaranteed, the internal enclosure will nevertheless have a thickness as thin as possible, in order to best match the shapes of the external envelope and to limit the mass of the double enclosure.

[0010] Advantageously, the textile external enclosure further has an intermediate membrane extending substantially parallel to the upper membrane and the lower membrane, said intermediate membrane being connected to the upper membrane and the lower membrane by the lateral membrane. Such an intermediate membrane makes it possible to locally increase the thickness of the double enclosure, and thus to provide a positioning or wedging imprint for it. More precisely, the presence of the intermediate membrane makes it possible to discretize the space available within the textile external enclosure, and to locally generate original interior space shapes (thanks to the interior volumes created), in particular discontinuous shapes such as, for example, discontinuous “staircase” shapes.By "discontinuous stepped shape" is meant any shape having a more or less regular sequence of steps (or levels) and risers connecting the steps, the steps being offset from each other in a first direction and extending parallel to each other in a second direction forming an angle with the first direction, the risers extending in the first direction. A possible application is for example when the double enclosure is part of a protective helmet, the presence of the intermediate membrane then providing a visor or a comfort zone for the helmet. Another application is when the double enclosure is part of a shoe sole, the presence of the intermediate membrane then providing a positioning imprint for the user's foot.Yet another application is when the double enclosure is part of a protective envelope configured to protect an object or package, the presence of the intermediate membrane then providing a cushioning footprint for the object or package. Optionally, the intermediate membrane may also be connected to the upper membrane and the lower membrane by the plurality of partitions.

[0011] The double enclosure may comprise a single internal enclosure or, alternatively, a plurality of internal enclosures. Each enclosure may then be inflated independently of the other internal enclosures, to a distinct pressure level. It is also possible for the double enclosure to be designed so that different combinations of internal enclosures must be inflated depending on the intended application. For example, if the double enclosure is used to protect a fragile package, depending on the shape of the package to be protected, which may be tubular, flat or parallelepiped for example, certain internal enclosures may be inflated or deflated. Similarly, if the enclosure is used for a shoe sole, depending on whether the shoe is to be used for athletic performance or for comfortable walking, different internal envelopes may be inflated.Alternatively or in combination, the application may depend on the level of inflation of the inflated internal enclosure(s).

[0012] The double enclosure may include a connection network in the internal enclosure to utilize the displacement of air volumes and pressure during dynamic movement to improve the comfort or performance of the object. This network may include one or more mechanical gas control elements such as check valves, flow regulators, pressure regulators, or pressure relief valves. This connection network may also include pressure distribution channels. Adjusting the diameter of the channels may then allow the air volumes and pressures to be varied precisely within the double enclosure. The channels may, for example, be made of a plastic material, typically polyurethane, without this being limiting within the scope of the present invention.

[0013] The internal enclosures are preferably straight cylinders made of polyurethane.

[0014] The external enclosure is structured by an upper membrane and a lower membrane, connected to each other by a lateral membrane. Each membrane can be designed independently and attached to the others by any suitable fastening means, in particular by sewing, welding or gluing. In this case, each membrane can in particular be made using different materials and can be distinguished by the stitching and its workmanship.

[0015] Alternatively, the whole can be designed in one piece, for example by weaving, and the distinction between upper membrane, lower membrane and lateral membrane is then purely topological.

[0016] Partitions are positioned between the lower membrane and the upper membrane and may also be designed separately and fixed, preferably sewn, glued or welded, to the assembly, or alternatively may be designed in one piece. The partitions may be made of the same material as the side membrane or may be made of one or more different materials.

[0017] Advantageously, and in the case where the double enclosure is a sub-assembly of a product, the pattern and / or the plans of the external textile enclosure allow for a seam allowance instead of assembly with another element of the product allowing assembly by sewing, thus avoiding the use of other assembly means such as glue for example. When the double enclosure is part of a protective helmet, this solution allows for example to attach a sun protection visor or ear muffs to the helmet. When the double enclosure is part of a shoe sole, this allows the sole to be attached to the upper of the shoe. Such an external sewing solution can also allow for assembling by sewing elements external to the product.

[0018] Not all partitions necessarily have the same dimensions and are not necessarily made of the same materials. Indeed, it may be advantageous to have higher partitions in the center of the double enclosure, for example, in order to allow the internal enclosure to occupy a larger space and to be able to absorb greater pressure when a greater shock is anticipated in the center. Similarly, some partitions may be completely rigid so as not to deform under the pressure of the internal enclosure and to further constrain the shape of the double enclosure. Indeed, if the pressure exerted by the internal enclosure on either side of the partition is identical and balanced, the partition will remain flat. But it may happen that this balance is broken, either by the presence of other partitions, or when the double enclosure includes several independent internal enclosures that can be inflated to different pressure levels.Playing on the rigidity of the partition can then help compensate for this imbalance.

[0019] The partition distribution is advantageously asymmetrical, with a higher partition density resulting in less swelling of the internal enclosure and less pressure absorption. The partition distribution can thus be used to configure a pressure absorption profile on the double enclosure.

[0020] On the outer membranes, the balance between the pressure exerted by the inner enclosure and the tension of the outer enclosure created by the pressure exerted by the inner enclosure on the partitions creates a curved surface forming an angle at the partitions.

[0021] These angles can be used to obtain precise shapes that best fit the geometry of the intended application.

[0022] This succession of angles creates a certain undulation which can be controlled by varying the ratio between the spacing of two successive partitions and their height. By providing a sufficiently small spacing between the partitions, it is possible to limit the curved nature of the external membranes, especially if they are reinforced with semi-rigid materials, and thus obtain substantially flat or angular surfaces.

[0023] Angular shape means a shape that cannot be explained by the sole application of homogeneous pressure on the enclosure, and is characterized by changes in the orientation of the surface forming angles, i.e. points or segments of the surface that are not derivable if we consider the thickness of the partitions as the elementary length of derivation.

[0024] Advantageously, the inner enclosure has a larger dimension corresponding to the shorter surface of the outer surface of the textile outer envelope with which it is configured to be in contact once inflated. This makes it possible in particular to avoid the formation of folds which occur if the inner enclosure is of too large dimensions.

[0025] The inner enclosure can be fixed, preferably sewn, to the outer enclosure, in several places in order to control its deployment during its inflation and to ensure good solidarity of the two enclosures.

[0026] Advantageously, the double enclosure is equipped with a valve, preferably retractable or designed for a needle pump, allowing the internal enclosure to be reinflated as needed. The double enclosure may also be equipped with one or more pressure indicators.

[0027] Thus, unlike prior art air cushion shoes for example, it is possible to re-inflate the sole when the pressure decreases over time and under significant stress, or even to adapt the inflation level in the event of a change in the use of the shoe.

[0028] The invention also relates to a shoe sole comprising a double enclosure according to the invention configured to absorb an increase in pressure caused by a step.

[0029] Such an increase in pressure is heterogeneous, mainly located at the heel and forefoot. The distribution of the partitions is therefore advantageously organized with a lower density in these areas. Rigid reinforcements can also be provided in these areas which are particularly stressed and sensitive to wear.

[0030] Such a shoe sole according to the invention advantageously makes it possible to stabilize the runner's foot as well as to recenter it within the shoe.

[0031] The double enclosure of the sole according to the invention may advantageously comprise a connection network arranged at the heel of the sole and making it possible to use the runner's weight to allow the transfer of air volumes and pressure during a dynamic movement in order to regulate the pressure of the assembly. Such a connection network makes it possible in particular to distribute the flows of air volumes and pressures between the front and the rear of the sole, at the time of the runner's step (rolling "from the heel"). Thus, manual re-inflation of the double enclosure is no longer necessary. This connection network may comprise mechanical gas control elements such as non-return valves, flow regulators, pressure regulators, or overpressure valves. This connection network may also comprise pressure distribution channels.Playing with the diameter of the channels can then make it possible to vary the air volumes and pressures precisely within the double enclosure of the sole. The channels can, for example, be made of a plastic material, typically polyurethane, without this being limiting within the scope of the present invention.

[0032] The invention also relates to a protective helmet comprising a double enclosure according to the invention configured to absorb a shock. It may, for example, be a helmet for cyclists.

[0033] A helmet can be likened to a half-sphere. The double enclosure then preferably allows a double curvature to be given to the internal enclosure. One of these curvatures, radial, is for example given by the distribution and orientation of the partitions relative to each other while the other curvature, longitudinal, can be parallel to the orientation of the internal enclosures if they have the shape of cylinders which fill the external enclosure and give it its unfolding shape by inflating.

[0034] The invention also relates to a protective envelope comprising a double enclosure according to the invention configured to protect an object or a package from external shocks or friction.

[0035] These can be packages used to send fragile parcels by post, or protection systems to prevent damage to parts during their movement on conveyors in an industrial structure, for example.

[0036] Depending on the application, the reinforced parts and the response profile to the increase in pressure will be different: in the case of movement on a conveyor, we will mainly seek to protect against friction and it is possible to predict the parts of the protective envelope which will be most stressed, while in the case of a postal package, it is important to protect against impacts and it is not possible to predict which parts of the envelope will be most stressed.

[0037] Being able to deflate the internal enclosure(s) can advantageously greatly reduce the volume of the protective envelope, which can facilitate its reshipping and reuse.

[0038] The present invention will be better understood by reading the non-limiting example embodiment which follows and by examining the attached drawing in which:

[0039] is a schematic perspective view of a shoe sole according to a first embodiment of the invention,

[0040] is a schematic view from below of the sole of the,

[0041] is a schematic sectional view of the sole of the according to a vertical anteroposterior plane, and

[0042] is a schematic perspective and cross-sectional view (along a vertical plane) of a shoe sole according to a second embodiment of the invention.

[0043] In the figures, the relative proportions of the different constituent elements have not been respected and do not correspond to reality, for the sake of clarity.

[0044] In a first embodiment shown in Figures 1 to 3, the invention relates to a shoe sole comprising a double enclosure.

[0045] The double enclosure 1 consists of a textile envelope on the one hand and an inflatable bladder on the other.

[0046] The textile envelope is made of reinforced polyamide and is composed of an upper membrane 2 and a lower membrane 3, connected by a lateral membrane 4 and by partitions 5. The textile envelope may also include reinforcements (not shown) judiciously placed at certain points of the sole to reinforce it locally, in particular reinforcements made of rigid or semi-rigid materials.

[0047] The shapes of the various parts making up the textile envelope are created by laser cutting. Notching is carried out in areas with strong curvatures.

[0048] The various membranes 2, 3 and 4 are assembled by means of seams, welds or gluing. In the case of using seams to assemble the various membranes 2, 3, 4, the seams are made in such a way that the underside has no visible seams. Indeed, in addition to the unsightly appearance of the seams, they also constitute a point of weakness which should not be placed in a place likely to undergo significant stress, in order to increase the durability of the sole.

[0049] The bladder is made of polyurethane cylinders. To make these cylinders, a polyurethane film is cut into planks shaped to form a lower and upper part of the cylinder. One of the planks has an opening for inserting a valve. The two planks are then welded together to form the cylinder. A valve is then welded to the opening provided for this purpose.

[0050] Additional elements can then be inserted into the valve, such as a shell or fins.

[0051] When assembling the double enclosure, some cylinders are advantageously inserted into the textile envelope while all the assembly seams have not yet been made. Other cylinders can be inserted later.

[0052] Thus, the seam 21 is first sewn to the upper membrane 2, then a first cylinder is inserted before the seam 22 is in turn sewn to the upper membrane 2, trapping the first cylinder. A second cylinder is then positioned before the seam 23 traps it in turn. Finally, a third cylinder is positioned between the seam 23 and the outer seam 24 which traps the third cylinder.

[0053] The partitions 5 do not all have the same height, which allows the double enclosure to have an undulating shape that can best fit the arch of the foot.

[0054] At the center of the sole, the 5 partitions are closer together because this part of the sole will not be subjected to much stress. Conversely, at the heel and forefoot, the 5 partitions are further apart to provide larger chambers, suitable for larger and more frequent impacts.

[0055] Some partitions 5 do not extend the full height of the double enclosure, which may allow bladder cylinders to pass through them in a constrained manner.

[0056] The bladder has a retractable valve and a pressure indicator, not shown, allowing one of the three cylinders to be reinflated if the inflation level of one of them is no longer adequate for the use you wish to make of the sole.

[0057] Another shoe sole comprising a double enclosure 10 is shown in the, according to a second embodiment of the invention. In addition to the upper membrane 2, the lower membrane 3, the lateral membrane 4 and the partitions 5, the textile outer envelope of the double enclosure 10 also comprises several intermediate membranes 12. Each intermediate membrane 12 extends substantially parallel to the upper membrane 2 and the lower membrane 3, and is connected to the upper membrane 2 and the lower membrane 3 by the lateral membrane 4. The intermediate membranes 12 define discretized interior spaces which can be inflated independently of each other and independently of the spaces delimited by the partitions 5, which makes it possible to locally increase the thickness of the double enclosure 10, and thus to provide a positioning or wedging imprint for it.In the illustrated embodiment, the presence of the intermediate membranes 12 makes it possible in particular to locally generate discontinuous “staircase” shapes 14.

[0058] The expression "comprising a" must be understood as "comprising at least one" unless otherwise specified.

Claims

Double enclosure (1; 10) for absorbing a heterogeneous pressure increase following a shock or step comprising an outer textile enclosure and an inflatable inner enclosure, in which the outer textile enclosure has an upper membrane (2) and a lower membrane (3) connected to each other by a lateral membrane (4) and by a plurality of partitions (5), preferably sewn together, the partitions (5) being positioned so that the outer textile enclosure is forced to take an angular shape when the inner enclosure is inflated. Double enclosure (10) according to claim 1, characterized in that the outer textile enclosure further has an intermediate membrane (12) extending substantially parallel to the upper membrane (2) and the lower membrane (3), said intermediate membrane being connected to the upper membrane (2) and the lower membrane (3) by the lateral membrane (4). Double enclosure (1; 10) according to claim 1 or 2, characterized in that the outer textile enclosure comprises reinforcements, in particular reinforcements of rigid or semi-rigid materials. Double enclosure (1; 10) according to any one of the preceding claims, characterized in that the inflatable inner enclosure is made of a single deformable material. Double enclosure (1; 10) according to any one of the preceding claims, characterized in that the double enclosure (1; 10) comprises a plurality of inflatable inner enclosures, each inner enclosure being capable of being inflated independently of the other inner enclosures, to a distinct pressure level. Double enclosure (1; 10) according to any one of the preceding claims, characterized in that the double enclosure (1; 10) comprises a connection network disposed in the inflatable inner enclosure and configured to move volumes of air and pressure in the inner enclosure during a dynamic movement of the double enclosure (1; 10). Double enclosure (1; 10) according to claim 6, characterized in that the connection network comprises one or more mechanical gas control element(s) of the type check valves, flow regulators, pressure regulators or overpressure valves. Double enclosure (1; 10) according to any one of the preceding claims, characterized in that the distribution of the plurality of partitions (5) is asymmetrical. Double enclosure (1; 10) according to any one of the preceding claims, characterized in that the inflatable inner enclosure is fixed to the textile outer enclosure in several places. Shoe sole comprising a double chamber (1; 10) according to any one of the preceding claims, configured to absorb an increase in pressure caused by a step. Protective helmet comprising a double enclosure (1; 10) according to any one of claims 1 to 9, configured to absorb a shock. Protective enclosure comprising a double enclosure (1; 10) according to any one of claims 1 to 9, configured to protect an object or package from external shocks or friction.

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