ES2718392T3 - Inflatable helmet - Google Patents

Description

DESCRIPTION

Inflatable helmet

This specification refers to inflatable helmets, in particular, but not exclusively, for cycling and other leisure activities such as skateboarding.

Conventional cycling hard helmets provide reasonable protection to a cyclist in case the cyclist hits his head against a hard surface, such as when the cyclist falls or is thrown from his bicycle. However, such helmets are bulky, which means they can be uncomfortable to wear, and users may be tempted not to wear a helmet for this reason.

Various designs of inflatable helmets have been proposed, which can be deflated in a more compact and convenient way. However, these helmets may not offer the same protection as a hard helmet. A helmet protects the user both by extending an impact over a larger area and by absorbing energy by deformation. Some known inflatable helmets do not have sufficient rigidity, so they spread an impact and deform so easily, so that very little energy is absorbed.

A known helmet is in EP0394726, which in one embodiment shows a substantially grid-shaped lattice structure. This grid-shaped arrangement means that the helmet is vulnerable to collapse and deformation when forces are applied, particularly from the side. It also does not fold well. The object of the present invention is to provide a helmet that can be deflated in a more compact form that offers effective head protection.

In accordance with the present invention, a helmet according to claim 1 is provided.

The invention will now be described, by way of example, with reference to the drawings, of which

Figure 1 is a perspective view of the helmet in a deflated state.

Figure 2 is a longitudinal section of a longitudinal chamber.

Figure 3 is a cross section of a longitudinal chamber.

Figure 4 is a plan view of the helmet in a deflated state.

Figures 4a and 4b show a detail of Figure 4 when the helmet is changing from the deflated state to the inflated state.

Figure 5 is a cross section of the helmet in an inflated state.

Figure 6 is a schematic view of a connection strut in a deflated state.

Figure 7 is a schematic view of a connection strut in an inflated state.

Figure 8 is a cross section of a detail of the longitudinal chamber in a deflated state.

Figure 9 is a side elevation in partial section of a detail of the longitudinal chamber in a deflated state. Figure 10 is a cross section of a detail of the longitudinal chamber in an inflated state.

Figure 11 is a plan view of the safety indicator.

Figure 12 is a sectional view of the safety indicator.

Figure 13 is a bottom plan view of the safety indicator.

With reference to Figure 1, the helmet comprises a number of longitudinal chambers 20, generally arranged parallel to each other, and also referring to Figure 5, a number of connection struts 30, which connect each longitudinal chamber 20 with its neighbor.

With reference to Figures 2 and 3, each longitudinal chamber 20 comprises an inflatable chamber 22, surrounded by a flange 26 that is in a vertical plane along the longitudinal axis of the longitudinal chamber 20. The inflatable chamber comprises two walls 23, 23 'which enclose a volume of air 24. The longitudinal chamber 20 generally curved or arched along its long axis; As can be seen in Figure 2, both the inflatable chamber 22 and the flange may be curved, although to different degrees, and the lower surface of the inflatable chamber 22 and the upper surface of the inflatable chamber 22 may be curved to different degrees , and the lower surface of the flange 26 and the upper surface of the flange 26 may be curved to different degrees. The outer contour of the flange has a generally polar vector shape that adds strength to the curved air chamber that encompasses through this differential of vector space. The flange generally follows the upper surface (particularly when viewed from a side profile of an individual longitudinal chamber, or connecting strut, but separated from it by a generally constant distance), although to facilitate manufacturing, the upper edge of the flange It can be composed of flat edges while the shape of the longitudinal members can be a gradual curve.

With reference to Figure 1 and Figure 4, the longitudinal chambers 20 are shown here, although this number may, of course, vary. The length and curvature of each longitudinal chamber 20 increases as one moves from the leftmost longitudinal chamber 20 to a maximum in the center of the hull 10 (in this specific case, the fourth longitudinal chamber 20), before to decrease both in length and in curvature one moves to the camera more to the right. This gives the helmet a generally hemispherical shape, although flattened and elongated, similar to a conventional hard cycling helmet.

With reference to Figures 4 and 5, the connection struts 30 are also hollow, and are connected between the inflatable chambers 22 of each adjacent longitudinal chamber 20, so that all inflatable chambers 22 are in fluid communication. The connection struts may also have an outer ridge or flange along their length of the upper surface of the connection struts; A representative tab 27 is indicated in dotted lines in Figure 5, which can be repeated for each strut. For both the longitudinal members and the connecting struts, such tabs may be present just on the upper surface, just on the lower surface, or on both upper and lower surfaces simultaneously.

In a deflated state, when there is little or no air in the helmet, each of the inflatable chambers 22 is compressed in a generally flat state, which is in the same plane as each surrounding flange 26. Each longitudinal chamber 20 is flat against the adjacent longitudinal chambers 20, so that the entire structure of the hull 10 has a flattened shape that occupies a smaller volume.

When the air is forced into the helmet, each inflatable chamber 22 expands, so that the walls 23, 23 'are inclined around volume 24. The connection struts 30 also expand, as will be described in greater detail to continuation. The width of each longitudinal chamber 20 increases, and the distance between adjacent longitudinal chambers 20 increases, so that the structure expands or crushes like an accordion in one direction (i.e., perpendicular to the plane where each tab is located ). The resulting inflated shape is now similar to a traditional helmet and can be worn by a user.

With particular reference to Figure 5, during a fall or collision, a large component of the force experiences will generally be in a downward direction, radially inward, toward the head. The approximately oval shape of the inflatable chambers 22 allows for additional local expansion and deformation in the case of a force of such impact, and the flanges can also be flexed and deformed to provide greater damping.

The positions of the connection struts 30 are distributed over the length of the hull, so that when viewed from the side elevation, the number of matching connection struts 30 is kept to a minimum; that is, the connection struts on each side of the longitudinal members do not share a common axis (although their axes may be parallel). This staggered, offset or irregular distribution of the connection struts increases stability when external forces are applied. Ideally, the position of the connecting struts 30 along the lengths of the longitudinal chambers 20 is generally alternated to give an elliptical distribution (or alternatively, a diamond-shaped or reticular-shaped distribution). This neck rib acts not only as a structural support, but also distributes and channels any load along the hull in a restricted manner, redistributing any impact force with a uniform and fluid reactive autonomy through the geometric ability of the folding design without stress. This will also allow the helmet to fold towards a flatter configuration, since it minimizes the total thickness of the material, which helps reduce mass agglomeration at any point along the length of the compressed helmet. It will be noted that the helmet ideally does not include a circumferential ring, so the helmet is not restricted when folded.

Each outer ridge 26 will remain in a generally vertical position around each inflatable chamber 22. The resistance of each longitudinal chamber 20 is increased by the addition of the outer ridge 26, acting as a geometric structure to support and enclose the forces of the inflated chamber by reducing the flexion of the longitudinal chamber 20.

The outer ridge also reduces the surface area and, in the case of a fall or a crash, reduces friction between the hull and the ground or other surfaces, and thus prevents a sudden deceleration of the head that can cause stress on the user neck The flange also protects the inflatable chambers from external abrasion during daily use.

With reference to Figures 6 and 7, each connecting strut 30 comprises a generally tubular wall 32 extending between the openings 34 formed in the walls 23 of the neighboring inflatable chambers 22. The openings 34 have a rhombic or diamond shape. The connection strut 30 can be formed with a fold of folds 37 in the flattened state, so as to help achieve the rhombic cross section in the inflated state of the hull. When the helmet is in a compressed and deflated state, the connecting strut 30 is flat, with the wall 32 folded along two edges 35, 36 (extended between two opposite corners of the rhombus). In this state, the connecting strut 30 and the walls 23 of the inflatable chambers 22 are all in parallel planes. Alternatively, the connection strut may have a circular tubular section, or an elliptical, oval or lenticular tubular section; likewise, the openings 34 can be circular, elliptical or lenticular, the connection strut can have two fold lines 37 (which make up a lenticular section) or no fold lines. A fold line or a pair of fold lines may occur in the region where the flange or crest is executed. The absence of folding lines (and corners in the opening) with an elliptical shape eliminates weak points and seams.

When the hull is inflated and the inflatable chambers 22 and the connecting struts 30 are filled with air, the connecting strut 30 expands to a more tubular shape, with a generally elliptical cross section (although the section could have more sections and corners straight, for example, a rhombic shape, and the section can change along the length of the connection strut). In this way, a complex arrangement of structural supports is formed that interlace the cross-striated chambers to form a hollow geometric structure. The addition of air effectively deploys this structure by creating a geometrically prestressed protective cage. At the same time, the distance between the walls 23 of the inflatable chambers 22 increases, and the angle formed by the strut 30 connecting with the walls 23 increases from 0 ° to closer to 45 °, in the form of hinges, so that The structure as a whole, considered in plan, acts as a network of folding parallelograms, as illustrated in Figures 4a and 4b. The geometry of the inflatable chamber 22 and the connecting struts 30 does not allow the walls 23 of the inflatable chambers 22 to remain perfectly flat, and the connecting strut 30 is folded into a rhombic cross section with perfectly flat sides, in the inflated state , from a perfectly flat folded structure in a deflated state. Since the hull material is ideally chosen to be flexible but not stretchable, when the connection struts 30 expand, the walls 23 of the inflatable chambers 22 curve around the opening 34, and the wall and the edges of the struts 30 connection will not be perfectly straight and flat. This generally elliptical or rhombic cross section provides structural support and increases the rigidity of the transverse forces acting on the hull.

With reference to Figures 8, 9 and 10, the shape of each inflatable chamber 22 can be restricted in the inflated position by internal reinforcing straps. A belt 38 is formed with each end attached to opposite walls 23, 23 'of an inflatable chamber 22 during manufacturing. When the inflatable chamber 22 is in the non-inflated state, the reinforcing belt is in a loose state, generally flat and in the plane of the flat walls 23, 23 ', possibly arranged in an eight-shaped loop. The length of the belt 38 is chosen in such a way that when the helmet is filled with air and the inflatable chamber 22 is inflated, the belt is tensioned between the walls 23, 23 'when they are separated at their midpoints (i.e. the widest point when the inflatable chamber 22 is inflated). When the belt 38 reaches its maximum extension, it limits the expansion of the inflatable chamber 22.

In general, then, the hull structure is one in which, considered in plan, the longitudinal members and the connecting strut members expand from a deflated state where the longitudinal members and the connecting strut members are in a approximately parallel state with a small total width, to an expanded reticular type structure, with the longitudinal members still parallel, and the connecting strut members all inclined to the longitudinal members, to give the structure the required width. Ideally, all connecting strut members will be inclined to the same degree, although also the lengths and / or angles of the connecting strut members could be varied to create different separations between the longitudinal members or even make the longitudinal members diverge. of a parallel arrangement. In addition to having laterally anchoring or intersecting points not aligned with the longitudinal members, the connecting strut members alternate ideally so that (as shown in Figure 4, 4a and 4b) some are oriented approximately 45 ° positively and others oriented 45 ° negatively in the inflated state, although it will be appreciated that, ideally, the connected struts could all be aligned identically.

The helmet is ideally composed of a single material made as a single integral part. The material is chosen in such a way that, ideally, it does not stretch more than approximately 5%, so the shape is restricted so that, once inflated, it does not deform too much (or make a balloon), thus maintaining its shape and thus providing an effective protective cover that can withstand adequate tolerances of elongation at break. Suitable materials are high density polyethylene (HDPE or PEHD), Nylon or material with similar properties, but can also be achieved by using carbon fiber and rubber with an internal Kevlar®, polyester or Nylon fabric. The material can be formed in the shape of the helmet, either by printing or by another process of flat forming, injection molding, or by forming flat elements together and then joining them together. These materials also have adequate tensile strength and resilience, without being fragile or prickly, both in normal use, repeated inflation and deflation cycles, and in case of impact.

A more stretchable material could be used, although it may be necessary to provide a larger internal reinforcement (such as a polyester, nylon or carbon fiber fabric or a dropped stitch reinforcement), which prevents excessive inflation and maintains the correct internal pressure.

The use of these types of helmet material allows the helmet to be formed as a single skin shape (with a single continuous topological surface).

Typically, the flanges 26 of the walls of the inflatable chambers 22 and the connecting struts 30 comprise a single layer of material, formed as a single homogeneous piece, with an approximately constant thickness of 0.7 to 1 mm. A suitable method for manufacturing the helmet is by means of the 3D printing technique, for example, molten deposition, which forms the helmet in its compressed state, although other techniques such as selective laser sintering, stereo lithography and methods yet to be developed.

Internal belts can be formed simultaneously. This technique is particularly suitable for forming material with the tolerance required to produce opposite walls of the inflatable chamber 22 and the connecting strut 30, the walls that are almost flat with each other (and also between the neighboring walls of the inflatable chambers 22 and the connection strut 30) with little separation in the uncompressed, compressed state, but still remains different and without the adjacent walls adhering to each other. The hull could also be formed by injection molding or printed in a state that is not completely flat and compressed.

Ideally, an adjustable chin strap can be attached at two points on opposite sides of the helmets, so that the inflated helmet is held firmly on the user's head when in use, with handles or attachment points formed on the helmet for this purpose.

The helmet is formed as a completely sealed unit with a valve that can be used to inflate the helmet. Usually, this will be a standard Schrader valve, a common component to cycling due to its reliability. It also means that the helmet can be inflated with a standard bicycle pump.

An excessive amount of pressure applied to the helmet, either during its inflation, or as a result of a fall or impact against the helmet, can damage the helmet material, and possibly cause an earlier, sudden and catastrophic failure, either during the normal use or during an impact, so that the helmet becomes useless or does not provide sufficient impact protection.

With reference to Figures 11 to 13, a safety indicator 40 is included somewhere outside the helmet, preferably near the inlet valve. A circular area 42 is included in the wall 23 of the hull (typically in one of the most lateral inflatable chambers 22), the wall 23 in this area is flat on the outer surface of the wall 23, but slightly concave 43 on the inner surface , so that the thickness of the wall material at 44 decreases towards the center of the circular area 42. In the center of the circular area, a brightly colored circular region 45 may be included in the outer surface. Rupture lines 46 extend around the circular region, and in a radial formation extending outward from the circular region. A particularly thin weak point 48 may be included, for example, in the center of the circle.

The shape and thickness of the wall material in the circular area 42, and the configuration and depth of the break lines 46, are formed such that when a predetermined pressure is reached or exceeded, the break lines and / or the weak point will be torn, and this tearing will spread rapidly along part of the break lines. When this occurs, the rupture will be very evident since the brightly colored circular region will be torn, distorted or not visible at all.

The necessary shape and thickness of the wall material in the circular area 42, and the configuration and depth of the break lines 46, can be determined by producing a range of configurations by varying the parameters of shape, thickness, configuration, depth etc. for a particular material, and destructively test each configuration until one is found that breaks at the required pressure.

In addition to the absolute release valve, a secondary release valve is incorporated into the pressurization valve as a "controlled release system". This controls the maximum amount of air pressure that is allowed to enter the hull, which protects the structure from excessive inflation very accurately up to about 8 psi from the maximum safety pressure. This valve will also allow the controlled and counter-reactive autonomous release of air during impact through the pre-primed valves and spring-die calibrated load release, thus reducing the impact force by diverting this force through this device. reactionary, creating an anti-recoil energy absorption system. This also prevents the absolute destruction of the unit by preventing stresses from being added during impact and, therefore, increases the overall safety factor of the helmet.

Claims (15)

1. A helmet (10) having a plurality of substantially longitudinal members (20) disposed side by side, the longitudinal members (20) being in fluid communication with each other, having a first inflated state where the longitudinal members (20) are distributed to shape a substantially concave or dome shape, which has a second compressed state where the longitudinal members (20) are flat and substantially coincident with each other, characterized in that each longitudinal member is separated from the neighboring longitudinal members (20) by a member ( 30) connection in a reticular type configuration and where the intersection between the connection members (30) in a longitudinal member (20) is not coincident when considered from the side. 2. A helmet (10) according to claim 1, wherein the connecting members (30) include a flat rib or fin extending from the surface of the connecting member (30). 3. A helmet (10) according to claim 1 or 2 wherein the connecting members (30) have an elliptical section. A helmet (10) according to any one of claims 1 to 3, wherein the intersection between the connecting members (30) in the adjacent longitudinal members (20) is not coincident when considered from the side. A helmet (10) according to any one of claims 1 to 4, wherein the connecting members (30) are substantially parallel to the longitudinal members (20) in the compressed state, but form an angle with the members (20) Longitudinal in the inflated state. 6. A helmet (10) according to claim 5, wherein the angle of the inflated state does not exceed 60 degrees. 7. A helmet (10) according to claim 6, wherein the angle of the inflated state does not exceed 45 degrees. A helmet (10) according to any preceding claim, wherein the longitudinal members (20) and / or the connecting members (30) have a generally elliptical, lenticular or rhombic shape that can be folded flat in the compressed state. 9. A helmet (10) according to any preceding claim wherein the helmet (10) is made of HDPE or nylon. 10. A helmet (10) according to any preceding claim wherein the helmet (10) is manufactured using a 3D printing technique. 11. A helmet (10) according to claim 10, wherein the 3D printing technique is molten deposition. 12. A helmet (10) according to claim 10, wherein the 3D printing technique is selective laser sintering. 13. A helmet (10) according to claim 10, wherein the 3D printing technique is stereo lithography. 14. A helmet (10) according to any preceding claim, wherein the helmet (10) includes an indicator (40) showing the user when the helmet (10) has been inflated to the correct pressure. 15. A helmet (10) according to any preceding claim, wherein the helmet (10) includes an indicator (40) that shows the user when the helmet (10) is not safe because the pressure has been exceeded.