Helmet and Fabrication Method

The invention relates to a helmet and to its manufacturing method.

In the fields of rope access work, rope access technicians are equipped with a great deal of safety equipment including a helmet. The helmet is designed to be fixed on the head and has to protect the user against the different types of impacts. To withstand increasingly violent impacts without increasing the weight of the helmets, work has been carried out on the crown as regards both the shape and the materials constituting the latter, and also as regards the means for attaching the crown to the user's head.

In addition to these issues, a requirement also exists as regards control of the temperature inside the helmet, more particularly when the outside temperature rises and/or intense efforts are made.

To improve thermal comfort, the helmet can be provided with one or more through holes that open out facing the user's head so as to create an air flow. This air flow enables the space between the head and the crown or the foam liner to be swept to reduce the temperature inside the helmet.

For obvious safety reasons, while at the same time keeping a reasonable size and weight, it is not possible to make holes in a large number of parts of the crown, with the result that the holes are generally present on the right and left lateral portions of the crown.

Independently from its position on the crown, the presence of a through hole passing through the thickness of the crown corresponds to the presence of a tunnel that opens out directly facing the user's head. It is apparent that under some particular conditions, in particular in tree-pruning activities, a branch or other slender item may pass through the tunnel and strike the user's head when a relative movement occurs between the branch and crown, for example a branch that moves with a substantially horizontal movement directed towards the inside of the volume delineated by the crown.

To avoid such a nuisance, certain pruning helmets are not provided with through holes, thereby preventing formation of an air flow in the upper part of the inside volume of the helmet. An alternative embodiment consists in making holes of small cross-section. As the cross-section is small, the air flow is very limited, which means that a large number of holes are required. Nevertheless, formation of a large number of holes naturally results in an impairment of the mechanical performances, requiring other modifications to be made on the crown.

It is observed that it is difficult to form a helmet for mountaineering or for working at heights that enables a significant air flow to be had in the top part of the crown while at the same time providing a high degree of protection.

It is observed that the problem of ventilation is also present in other categories of helmets, in particular skiing helmets that have a rigid crown inside which a foam liner is placed. The crown defines through holes, and the foam liner also defines through holes that are staggered and/or a netting is fitted between the crown and foam liner. It should be noted that the ventilation problems are different as the skier is moving at high speed, the activity takes place in rather low temperatures and the impacts present a different typology, thus enabling other trade-offs to be made as regards the configuration and position of the through holes, with the result that the holes are mainly provided on the top of the helmet. Furthermore, such a configuration is not attractive for a helmet for mountaineering or for working at heights, as it implies providing a helmet that is heavier and more voluminous in order to comply with different regulatory requirements, in particular as regards the resistance to perforating impacts arising from objects falling on the top of the helmet.

One object of the invention consists in providing a helmet that enables a better trade-off to be made between protection and ventilation of the inside of the crown without impairing the other parameters of the helmet.

This issue tends to be solved by means of a helmet designed for working at heights and for mountaineering comprising:

The helmet is remarkable in that it comprises a diverter attached to the crown and arranged between the crown and the space designed to receive a user's head delineated by the cap to divert an object entering via one of the first through holes;

In a preferred embodiment, the diverter delineates several second through holes separated by second studs to define a second ventilation area. The second through holes have a smaller area than an area of the first through holes facing the second through holes in the first direction.

Preferentially, each first through hole is facing at least two second through holes in the first direction.

In advantageous manner, the diverter is installed removable from the crown.

Preferentially, a shutter is installed movable with respect to the first ventilation area between a closed position where the first through holes are blocked by the shutter and an open position where the shutter is not facing the first through holes in the first direction.

According to one embodiment, the diverter is installed movable with respect to the crown between a protection position and another position in which the shutter is installed fixedly secured to the diverter. The protection position is a position where the diverting wall is facing the first ventilation area in the first direction. The other position corresponds to the closed position of the shutter.

It is a further object of the invention to provide a manufacturing method of a helmet that enables a trade-off between ventilation and protection of the head to be improved.

This result tends to be achieved by means of a method for manufacturing a helmet comprising the following steps:

represent a protection helmetprovided with a crownand a cap. The capis designed to receive the user's head. The capenables the user's head to be placed at a distance from the crown. The capis preferentially fixed to the crown. The capcan be in the form of a set of wire elements, for example webbing straps, as is well known in the technical field to define an empty space propitious to creating an air flow.

The crownis made from a material that is unable to fold onto itself. The crowncan preferentially be made from a plastic material for example from polycarbonate or injection-moulded ABS or from polystyrene or expanded polypropylene, or from any other plastic material, in particular injection-moulded, thermoformed or foam plastic.

The crownhas a peakand a base. The crown wall extends from the baseto the peakin a heightwise direction ZZ that corresponds substantially to the longitudinal direction of the user once the helmet is being worn.

The basecan define a supporting plane that corresponds to the horizontal plane tangent to the lowest point of the crownwhen the user is wearing the helmet. Preferentially, the supporting plane is defined by at least three points of the basethat are pressing on a plane when the helmetis placed on a support.illustrates the supporting plane AA.

The crowndefines a crown surface that represents the surface of the median plane of the crown in the thickness direction. The crown surface is a curved surface that is approximately a half-sphere.

To remove of a part of the heat given off by the user's head, the crownhas a crown wall that defines several first through holes. The first through holesare preferentially right first holes and left first holes, i.e. first holes arranged in the right-hand part and the left-hand part with respect to a median sagittal plane of a user wearing the helmet. It is also advantageous for the right first through holes and the left first through holes to be arranged symmetrically with respect to the median sagittal plane. It is further possible to have front first holes and/or back first holes as alternatives or as complements to the right and left first holes.

As illustrated inand in, the first through holeis pass-through in the thickness direction, i.e. in the direction connecting the inner face of the crownand the outer face of the crown. The first through holesare also pass-through in a first direction that is parallel to the supporting plane AA.

The right and left first through holesare designed to enhance the presence of an air flow inside the helmetbetween the crownand the user's head, at least in the top part of the crown. The first through holescan be of any shape. The shape of the first through holescan differ between the multiple first through holes.

The first through holesare separated from one another by first studs. The first through holesdefine a first area. It was observed that to have an air flow ensuring an efficient heat removal, it is necessary to have large first through holes. The first through holeshave large cross-sections without penalising the mechanical performances of the crownin response to impacts.

To encourage the presence of an efficient air flow, the first through holeseach have a first area that is as large as possible, for example more than 1 cm, preferentially more than 2 cm, more preferentially more than 5 cmand even more preferentially more than 8 cmor 10 cm.

However, the larger the value of the first area, the easier it is for the cross-section of a foreign body, for example a twig or branch, to get inside the crown. Furthermore, the risk of injury increases with the cross-section of the foreign body.

To maintain a large air flow while reducing the probability of the head coming into contact with a foreign body entering from outside the crown, the helmetis provided with a diverter. The divertercomprises a diverting wall′ arranged inside the volume bounded by the crownand the volume designed to receive the head and represented by the cap. The diverteris located facing the first through holesin the first direction. The diverteris located between the crownand the cap, i.e. between the crownand the volume representative of the user's head.

Preferentially, the diverteris fixed to the crown. The diverterhas a diverting wall′ that is distinct from the crown wall. The diverting wall′ is rigid or substantially rigid.

The diverting wall′ is for example made from plastic, metal or wood. The diverting wall′ is not a netting attached to the crown.

In a particular embodiment, the diverting wall′ opposes a thrust force with a value of 1 kN in the direction of the cap. This prevents a foreign body from reaching the user's head.

The diverting wall′ extends from the area facing the first through holesin the direction of the peakof the crown. The diverting wall′ is terminated by a top end that represents the end closer to the peak, i.e. opposite a bottom end that is closer to the base. Such resistance is not possible with the cap, which must be flexible to provide the expected comfort.

The diverting wall′ defines at least one portion with an inclined surface that is globally directed towards the peakof the crown. The inclination of the diverting wall′ enables a foreign body that enters from outside through one of the first through holesto slide against the diverting wall′ and be directed towards the peakof the crown. More precisely, the diverting wall′ is inclined in the direction of the space situated between the peak of the capand the peakof the crownwithout passing through the surface delineated by the cap.

The top end of diverting wall′ is located between the crownand the capso that any imaginary line tangent to the top end and passing through the first through holespasses through the crownwithout passing through the space receiving the user's head delineated by the cap. A foreign body can enter the crown through a first through hole. The foreign body comes into contact with the diverting wall′ and slides along the diverting wall′ until it leaves the diverter. The foreign body is then tangent to the top end. The alignment between the top end and the first through holes prevents a rectilinear foreign body from being able to penetrate into the volume designed to receive the user's head.

The diverting wall′ will oppose movement of the foreign body in the first direction in the direction of the capto prevent contact with the user's head and/or the inclination will direct the foreign body to the space situated between the peak of the capand the peakof the crownwithout passing through the cap, so that the foreign body moves in an area where the risk of contact with the head is very slight or even nil. This avoids having to form a diverterthat is stronger and therefore bulkier and heavier. The deviation can result in the foreign body being wedged against the first studs, thereby also reducing the risk of injury. If the foreign body enters the helmetwith a downward path, the divertermoves towards the crownand forms a blocking part. The deviation wall′ prevents the external element from penetrating into the crownuntil it reaches the space intended to receive the user's head or press on the cap.

For example, the diverterdefines an inclined surface that extends mainly in a direction connecting the peakof the crownand the right or left lower end of the crowndepending on whether the diverteris fixed to the right part or to the left part of the crown. The angle of inclination of the diverting wall′ and especially the position of the top end can be adjusted according to the position of the first through holes, the curvature of the crownand the available space between the capand the crown. The same can be the case for an installation on the rear or front part of the crown.

The diverterhas an inclination close to that of the crownin the area facing the first ventilation area while being different in order not to reduce the volume accessible for the user's head without reducing the ability to accept an air flow.

In an observation along a cutting plane perpendicular to the supporting plane AA, the wall of the crownand the wall of the diverterare distant and move away from one another when moving in a heightwise direction ZZ perpendicular to the supporting plane away the supporting plane AA in the direction of the peak. In other words, the structure delineated on the one hand by the wall of the crownand on the other hand by the wall of the diverterflares out in the direction of the peak. The diverting wall′ and the inner wall of the crown define a duct that opens out to enable an air flow to pass in a top part of the helmet. The duct flares out in the direction of the peakto facilitate the presence of a large air flow.

It is particularly advantageous for the diverternot to define a surface parallel to the surface of the crownand for the diverterto move progressively away from the crownwhen moving away from the supporting plane AA. Observation of the separating distance between the crownand the diverteris made in sectional planes that are perpendicular to the supporting plane AA. The separation between the crownand the diverterenhances the formation of an air flow in the inner top part of the crowneliminating formation of an obstacle above the area receiving the user's head. It is also advantageous to form a rim in order to have a minimum separating distance between the crown wall that defines the first through holesand the wall of the diverter. This minimum space ensures that a minimum air flow is captured for the helmetto be correctly ventilated.

As illustrated in, it is particularly advantageous for the diverterto extend facing the first through holesat least over the whole of the facing surface between the first through holesand the space accessible for the head bounded by the capin the first direction.

In a preferred embodiment, the diverterextends underneath the first through holes. More preferentially, the diverteris in contact with the crownor is separated from the crownby a smaller distance than a threshold value, for example less than 6 mm or less than 4 mm or less than 2 mm, to prevent a foreign body having a larger diameter than the threshold value from passing between the crownand the diverterin the first direction as illustrated inthat is parallel to the median sagittal plane and represents the vertical direction. Bringing the crowninto contact with the diverterimproves the mechanical performances.

As an exemplary embodiment illustrated in, the crowndefines a rim defining the first through holes. The attachment between the diverterand the crownis situated on one side of the rim whereas the first through holesare situated on the other side of the rim.

To enhance the air intake, it is advantageous for the wall of the diverterto be offset from the wall of the crownby several millimetres. It is particularly advantageous for the diverternot to be in contact with the crownand for the wall of the diverterto extend in the direction of the top part of the crownso as to form an opening enhancing removal of the air flow in the top part of the crown. The air passing through the crowncomes into contact with the diverterthat does not delineate a closed volume. As the divertermoves progressively away from the crownwhen approaching the peak, it is easy for the air that enters to flow towards the peakof the crownthereby achieving an air flow that is able to remove heat.

As illustrated in, to facilitate the presence of an air flow as close as possible to the top of the user's head, it is advantageous for the diverterto define several second through holesarranged facing the first ventilation area. The facing direction is the first direction.

The second through holesare separated from one another by second studs.

It is advantageous for the second through holesto be facing the first through holesand more preferentially for the second through holesto present a smaller cross-section than the cross-section of the first through holes. A large quantity of air enters via the first through holesand a part of this quantity of air passes through the second through holes, the rest passing along the second studsin the direction of the peakof the crown.

As the diverteris located inside the crown, it is not intended to withstand the same impacts as the crown. It is advantageous to form a diverterthat is as ventilated as possible in order not to limit the air flow entering via the first through holestoo greatly.