TWI830001B - Item of protective headgear and method of assembling the protective headgear - Google Patents

Abstract

According to an aspect of the invention there is provided a connector for connecting inner and outer layers of an apparatus, the connector comprising: a first attachment part for attaching to one of the inner or outer layers; a second attachment part for attaching to the other of the inner or outer layers; wherein: the first and second attachment parts are connected in such a way as to allow the first attachment part and second attachment part to move relative to each other when the inner and outer layers move relative to each other, and the first attachment part comprises: a first flange portion adjacent a gap, said gap for accommodating a portion of said one of the inner or outer layers, said flange portion retaining said inner or outer layers within said gap, and wherein the first flange portion is substantially dome-shaped.

Description

Protective helmets and methods of assembling protective helmets

The present invention relates to a connector between an inner part and an outer part of a device. In particular, the invention relates to devices, such as helmets, that may include a sliding interface between two components.

Helmets are known to be used in various activities. Such activities include combat and industrial uses, such as, for example, protective helmets for soldiers, and hard hats or helmets used by builders, miners or operators of industrial machinery.

Helmets are also commonly used in sports activities. By way of example, protective helmets may be used in: ice hockey, cycling, motorcycling, racing, skiing, snowboarding, ice skating, skateboarding, equestrian activities, American football, baseball, rugby, soccer, skateboarding Ball, lacrosse, rock climbing, golf, airsoft, roller derby and paintball.

Helmets can be fixed-sized or adjustable to fit different sizes and shapes of heads. In certain types of helmets (eg, typically in ice hockey helmets), adjustability can be provided by moving parts of the helmet to change the outer and inner dimensions of the helmet. This can be achieved by having the helmet have two or more parts that can move relative to each other. In other cases (for example, typically in cycling helmets), the helmet is provided with attachment means for securing the helmet to the user's head, and the attachment means can vary in size to fit the user's head ,and The main body or shell of the helmet remains the same size. In some cases, comfort padding within the helmet may serve as an attachment device. The attachment means may also be provided in the form of a plurality of physically separate parts (for example, a plurality of comfort pads that are not interconnected with each other). These attachment means for placing the helmet on the user's head can be used with additional strap means, such as a chin strap, to further secure the helmet in place. Combinations of these adjustment agencies are also possible.

Helmets are usually made of an outer shell, which is usually hard and made of plastic or composite materials, and an energy-absorbing layer, called a liner. In other configurations, such as a rugby scrum cap, the helmet may not have a hard outer shell and the helmet may be flexible as a whole. In either case, protective helmets must now be designed to meet specific legal requirements involving, inter alia, the maximum accelerations that may occur at the center of gravity of the brain under specified loads. Typically, tests are performed in which a so-called simulated skull equipped with a helmet is subjected to radial blows towards the head. This has resulted in modern helmets having good energy absorption capabilities in the event of a radial blow to the skull. Developments have also been made to reduce the energy transmitted from an oblique strike (i.e., its combined tangential and radial components) (by absorbing or dissipating rotational energy and/or redirecting it as translational energy rather than (e.g., WO 2001/045526 and WO 2011/139224, the entire contents of which are incorporated herein by reference).

These oblique impacts (in the absence of protection) cause both translational and angular accelerations of the brain. Angular acceleration causes the brain to rotate within the skull, which causes damage to the body components that connect the brain to the skull and to the brain itself.

Examples of rotational injuries include: mild traumatic brain injury (MTBI), such as concussion; and severe traumatic brain injury (STBI), such as subdural hematoma (SDH), bleeding due to ruptured blood vessels, and diffuse axial DAI can be summarized as the excessive stretching of nerve fibers due to high shear deformation in brain tissue.

Depending on the characteristics of the rotational force (such as duration, amplitude, and rate of increase), one may suffer concussion, SDH, DAI, or a combination of these injuries. Generally speaking, SDH occurs in the case of accelerations of short duration and large amplitude, while DAI occurs in the case of longer and wider acceleration loads.

In helmets that reduce the rotational energy transmitted to the brain caused by oblique impacts, such as those disclosed in WO 2001/045526 and WO 2011/139224, two parts of the helmet can be configured to rotate at an angle. Slide relative to each other after impact. Connectors may be provided that connect parts of the helmet together while allowing the parts to move relative to each other upon impact.

In order to provide such a helmet, it may be desirable to provide two components that are slidable relative to each other, thereby providing a sliding interface. It would also be desirable to be able to provide such a sliding interface without substantially increasing manufacturing cost and/or effort.

According to a first aspect of the present invention, there is provided a connector for connecting an inner layer and an outer layer of a device, the connector comprising: a first attachment part for attaching to one of the inner layer or the outer layer. or; a second attachment part for attachment to the other of the inner layer or the outer layer; wherein: the first attachment part and the second attachment part are connected in a manner such that when the inner layer The first attachment part and the second attachment part are allowed to move relative to each other when the outer layer is moved relative to each other, and the first attachment part includes: a first flange portion adjacent a gap for receiving A portion of the one of the inner layer or the outer layer, the flange portion retains the inner layer or the outer layer within the gap, and wherein the first flange portion is substantially dome-shaped.

According to a second aspect of the present invention, a connector for connecting an inner layer and an outer layer of a device is provided. The connector includes: a first attachment part for attaching to the inner layer or the outer layer. one of the outer layers; a second attachment part for attachment to the other of the inner layer or the outer layer; wherein: the first attachment part and the second attachment part are connected in a manner to The first attachment part and the second attachment part are allowed to move relative to each other when the inner layer and the outer layer are moved relative to each other, and the first attachment part includes: a first flange portion adjacent the gap, the The gap is used to accommodate a portion of the one of the inner layer or the outer layer, and the first flange portion keeps the inner layer or the outer layer in the gap; separate first and second sections, the first A section is configured to connect directly to one of the inner layer or the outer layer, the second section is configured to connect the remainder of the connector to the first section, wherein: the first The first section of the attachment part includes: a first flange portion located at a peripheral portion of the first section; and a recessed portion located within the peripheral portion at a central region of the first section ; a through hole passing through the recessed portion; and the second section of the first attachment feature includes: another flange portion configured to be located within the recessed portion of the first section ; and a neck portion configured to pass through the through hole of the first section, the neck portion being connected to the remaining portion of the connector.

Optionally, the first flange portion of the first section and the flange portion of the second section together form a substantially flat continuous surface when located therein.

According to a third aspect of the present invention, a connector for connecting an inner layer and an outer layer of a device is provided, the connector comprising: a first attachment part for attaching to one of the inner layer or the outer layer. or; a second attachment part for attachment to the other of the inner layer or the outer layer; wherein: the first attachment part and the second attachment part are connected in a manner such that when the inner layer The first attachment part and the second attachment part are allowed to move relative to each other when the outer layer is moved relative to each other, and the second attachment part includes: a first part having a through hole therein; and a second part having a through hole therethrough. through the through hole and configured to attach to the other of the inner layer or the outer layer; wherein the first portion of the second attachment feature is configured such that the first portion can be spirally passed through the inner layer. layer or a hole in the one of the outer layer, and the first attachment feature is configured such that the first attachment feature cannot be threaded through the hole.

Optionally, the second part may be removable from the through hole in the first part of the second attachment part and configured such that the second part is located in the first part of the second attachment part. Do not screw through this hole when inside.

Optionally, this second part is a fastening member and includes a snap pin.

Optionally, the first portion includes an elongated tail protruding therefrom.

According to a fourth aspect of the present invention, a connector for connecting an inner layer and an outer layer of a device is provided, the connector comprising: a first attachment part for attaching to one of the inner layer or the outer layer. a second attachment part for attaching to the other of the inner layer or the outer layer; and an elastic member connecting the first attachment part and the second attachment part; wherein: the elastic A component is configured to be disposed between the inner layer and the outer layer and extend in a direction substantially parallel to the planes of the inner layer and the outer layer when the connector is attached to the inner layer and the outer layer; and When the connector is attached to the inner layer and the outer layer, the elastic member is biased in a direction perpendicular to the plane of the inner layer and the outer layer when in a neutral state, such that when the first attachment part is attached When attached to the one of the inner layer or the outer layer, the second attachment feature presses against the one of the inner layer or the outer layer.

Optionally, the first attachment feature includes a first flange portion adjacent a gap for receiving a portion of the one of the inner layer or the outer layer, the first flange portion attaching the inner layer to Or the outer layer is retained within the gap, and wherein the first flange portion is substantially dome-shaped.

Optionally, the first attachment feature includes: a separate first section configured to be directly connected to the one of the inner layer or the outer layer, the second section A section is configured to connect the remainder of the connector to the first section, wherein the first section of the first attachment feature includes a first flange portion located on the first section The peripheral part is separated by a gap, the gap is used to accommodate a part of the inner layer or the outer layer, the flange part keeps the inner layer or the outer layer in the gap; the concave part, which is located within the peripheral portion at a central region of the first section; a through hole extending through the recessed portion; and the second section of the first attachment feature including a flange portion configured to located within the recessed portion of the first section; and a neck portion configured to pass through the through hole of the first section, the neck portion being connected to the remaining portion of the connector.

Optionally, the second attachment feature includes: a first portion having a through hole therein; and a second portion passing through the through hole and configured to attach to the other of the inner layer or the outer layer ; wherein the elongated portion of the second attachment part is configured so that the elongated portion can be threaded through a hole in the one of the inner layer or the outer layer, and the first attachment part is configured so that it cannot Thread the first attachment part through the hole.

According to a fifth aspect of the invention, there is provided a device comprising: an inner layer and an outer layer configured to move relative to each other; and at least one connector as in any of the preceding aspects, the at least one connector A connector connects the inner layer to the outer layer.

Optionally, the inner layer and the outer layer are configured to move relative to each other at the sliding interface.

Depending on the situation, the device is attached to a protective hat.

Optionally, the first attachment part is attached to the inner layer.

Optionally, the inner layer is an interface layer configured to interface with the wearer's head.

According to a sixth aspect of the present invention, there is provided an assembly according to the fifth aspect of the present invention. A method of apparatus in one aspect: the method comprising spirally threading a second attachment member through a hole in one of the inner layer or the outer layer until the first attachment member is adjacent the hole; at the hole, through the first A flange portion attaches the first attachment feature to the one of the inner layer or the outer layer; and attaches the second attachment feature to the other of the inner layer or the outer layer.

1: 1st helmet/protective helmet/helmet/2nd helmet

2: Outer shell/rigid shell/hard shell/layer/hard layer

2': Softer inner/inner layer

2": Harder outer layer

3: Inner shell/energy absorption layer

3': Relatively thick inner layer/inner layer

3": Relatively thin outer layer/outer layer

3A: External parts

3B: Internal parts

4: Sliding layer/sliding accelerator

5: Connecting parts/fixed parts

5a: Fixed parts/suspended parts

5b: Fixed parts/suspended parts

5c: Fixed parts/suspended parts

5d: Fixed parts/suspended parts

6: Intermediate housing/optional adjustment device/adjustment device

7: Ventilation hole

8:Part One

9:Part 2

10: Head

11: Longitudinal axis

12: Displacement

13:Interface layer/attachment device

14:Inner shell

15: Helmet lining/lining

16:Comfort padding

17: Outer panel/board

20:Connector/First instance connector/Second instance connector

21: First attachment part

22: Second attachment part

23: Elastic parts/elastic parts

31: Card dunk/body

41:hole

211: First flange part/flange part/dome-shaped first flange part

212: Neck part

213: Second flange part/flange part

214:Gap

215: First section/first part

216:Second Section/Second Part

217: First flange part

218: concave part

219:Through hole

221:Part One

222:Through hole

223:Part 2/Fastening components

224: snap pin

225:Flange part

226: Extend tail/tail

2110:Flange part

2112:Second flange part

I: Front oblique impact/oblique impact

K: oblique impact/impact force/force

K _R :radial force

K _T : tangential force/helmet rotation tangential force

The present invention will be described in more detail below with reference to the accompanying drawings, in which: Figure 1 shows a cross-section through a helmet for providing protection against oblique impacts; Figure 2 is a diagram showing the working principle of the helmet of Figure 1; Figure 3A, Figures 3B and 3C show variations of the structure of the helmet in Figure 1; Figures 4 and 5 schematically illustrate another configuration of the helmet; Figures 6 to 9 schematically illustrate other configurations of the helmet; Figure 10 schematically illustrates schematically illustrates another configuration of the helmet; Figure 11 schematically illustrates another configuration of the helmet; Figure 12 schematically illustrates another configuration of the helmet; Figure 13 shows a first view of the first example connector; Figure 14 shows a second view of the first example connector connected to a device; FIG. 15 shows a third view of the first example connector screwed through a hole in a part of the device; FIG. 16 shows a first view of the second example connector View; Figure 17 shows a first part of the second example connector; Figure 18 shows a second part of the second example connector; Figure 19 shows a second view of the second example connector connected to a device; Figure 20 shows a third view of a second example connector connected to a device.

The thickness ratios of the various layers in the helmet shown have been exaggerated in the drawings for the sake of clarity and can of course be adapted as needed and required.

Figure 1 shows a first helmet 1 of the kind discussed in WO 01/45526, which is intended to provide protection against oblique impacts. This type of helmet can be any of the types of helmets discussed above.

The protective helmet 1 is constructed with an outer shell 2 and an inner shell 3 arranged inside the outer shell 2 and intended to be in contact with the wearer's head.

Disposed between the outer shell 2 and the inner shell 3 is a sliding layer 4 (also called a sliding accelerator or a low friction layer), which can achieve displacement between the outer shell 2 and the inner shell 3 . In particular, as discussed below, the sliding layer 4 or sliding promoter can be configured so that sliding can occur between the two parts during impact. For example, it may be configured to slide under forces associated with an impact on helmet 1 that is not expected to be fatal to the wearer of helmet 1 . In certain configurations, it may be desirable to configure sliding layer 4 such that the coefficient of friction is between 0.001 and 0.3 and/or below 0.15.

In the illustration of FIG. 1 , disposed in the edge portion of the helmet 1 may be one or more connecting members 5 interconnecting the outer shell 2 and the inner shell 3 . In some configurations, the connector can offset the mutual displacement between the outer housing 2 and the inner housing 3 by absorbing energy. However, this is not required. Furthermore, even where this feature is present, the amount of energy absorbed is generally minimal compared to the energy absorbed by the inner housing 3 during impact. In other configurations, the connecting part 5 may not be present at all.

Furthermore, the position of these connecting parts 5 can vary (for example, away from the edge). Partially positioned, and connecting the outer shell 2 and the inner shell 3) through the sliding layer 4.

The outer casing 2 is preferably relatively thin and strong in order to withstand various types of impacts. The outer casing 2 may be made of a polymer material such as, for example, polycarbonate (PC), polyvinyl chloride (PVC) or acrylonitrile butadiene styrene (ABS). Advantageously, the polymeric material may be fiber reinforced using materials such as fiberglass, aramid, Twaron, carbon fiber or Kevlar.

The inner shell 3 is significantly thicker and acts as an energy absorbing layer. In this way, it can reduce or absorb the impact on the head. It may advantageously be made from: foam materials such as expanded polystyrene (EPS), expanded polypropylene (EPP), expanded polyurethane (EPU), vinyl nitrile foam; or for example formed Other materials with honeycomb structures; or strain rate sensitive foams such as those marketed under the trade names Poron ^™ and D3O ^™ . The construction can vary in different ways, which are presented below with, for example, several layers of different materials.

The inner housing 3 is designed to absorb the energy of impact. Other elements of the helmet 1 (for example, the hard outer shell 2 or the so-called "comfort padding" provided within the inner shell 3) will absorb this energy to a limited extent, but this is not their main purpose, and they The contribution to energy absorption is minimal compared to the energy absorption of the inner housing 3 . In fact, although certain other elements (such as comfort pads) may be made of "compressible" materials and thus are considered "energy absorbing" in other contexts, it is generally accepted in the helmet community that A compressible material is not necessarily "energy absorbing" in the sense of absorbing a meaningful amount of energy during impact for the purpose of reducing injury to the helmet's wearer.

Several different materials and embodiments can be used as sliding layer 4 or sliding accelerator, for example, oil, Teflon, microspheres, air, rubber, polycarbonate (PC), fabric materials such as felt wait. This layer may have a thickness of approximately 0.1 mm to 5 mm, but may also be Other thicknesses may be used, depending on the material chosen and the desired performance. The number of sliding layers and their positioning can also vary, and examples of this are discussed below (see Figure 3B).

As connecting element 5 , for example, deformable plastic or metal strips can be used, which are anchored in a suitable manner in the outer and inner housings.

Figure 2 shows the working principle of the protective helmet 1, assuming that the helmet 1 and the wearer's head 10 are semi-cylindrical, with the head 10 being placed on the longitudinal axis 11. When the helmet 1 experiences an oblique impact K, torsional force and torque are transmitted to the head 10 . The impact force K causes both a tangential force K _T and a radial force K _R on the protective helmet 1 . In this particular context, only the helmet rotational tangential force K _T and its effects are of interest.

As can be seen, the force K causes a displacement 12 of the outer housing 2 relative to the inner housing 3, deforming the connecting part 5. A significant reduction in the torsional forces transmitted to the skull 10 can be obtained using this configuration. Typical reductions may be approximately 25%, but in some instances reductions as high as 90% may be possible. This is the result of the sliding motion between the inner housing 3 and the outer housing 2 reducing the amount of energy converted into radial acceleration.

Sliding movements may also occur in the circumferential direction of the protective helmet 1, although this is not shown. This may be the result of a circumferential angle of rotation between the outer housing 2 and the inner housing 3 (ie, during impact, the outer housing 2 may rotate up to a circular angle relative to the inner housing 3).

Other configurations of the protective helmet 1 are also possible. Several possible variations are shown in Figure 3. In Figure 3A, the inner housing 3 is constructed from a relatively thin outer layer 3" and a relatively thick inner layer 3'. The outer layer 3" is preferably harder than the inner layer 3' to help facilitate sliding relative to the outer housing 2. In Figure 3B, the inner housing 3 is constructed in the same way as in Figure 3A. In this case, however, there are two sliding layers 4 with an intermediate housing 6 between them. If so desired, the two sliding layers 4 can be embodied in different ways and made of different materials. For example, one possibility is to have lower friction in the outer sliding layer than in the inner sliding layer. In Figure 3C, the outer casing 2 is embodied in a different manner than before now. In this case, the harder outer layer 2" covers the softer inner layer 2'. For example, the inner layer 2' can be of the same material as the inner shell 3.

Figure 4 shows a second helmet 1 of the type discussed in WO 2011/139224, which is also intended to provide protection against oblique impacts. This type of helmet can also be any of the types of helmets discussed above.

In Figure 4, the helmet 1 includes an energy absorbing layer 3 similar to the inner shell 3 of the helmet of Figure 1. The outer surface of the energy absorbing layer 3 may be provided by the same material as the energy absorbing layer 3 (i.e. there may be no additional outer shell), or the outer surface may be a rigid shell equivalent to the outer shell 2 of the helmet shown in Figure 1 Body 2 (see Figure 5). In that case, the rigid shell 2 can be made of a different material than the energy absorbing layer 3 . The helmet 1 of Figure 4 has an optional plurality of vents 7 extending through both the energy absorbing layer 3 and the outer shell 2, thereby allowing air flow through the helmet 1.

An interface layer 13 (also known as attachment means) is provided to interface with (and/or attach the helmet 1 to the wearer's head). As discussed previously, this may be desirable when the energy absorbing layer 3 and rigid shell 2 cannot be adjusted in size, as this allows for accommodating heads of different sizes by adjusting the size of the attachment means 13 . The attachment means 13 may be made of an elastic or semi-elastic polymer material such as PC, ABS, PVC or PTFE or a natural fiber material such as cotton. For example, a textile cap or mesh may form the attachment means 13 .

Although the attachment device 13 is shown as including a headgear portion with other strap portions extending from the front, rear, left and right sides, the specific configuration of the attachment device 13 may vary depending on the configuration of the helmet. In some cases, the attachment means may be more similar to a continuous (formed) sheet that may have holes or gaps (eg, corresponding to the location of the vents 7) to allow air flow through the helmet.

Figure 4 also shows an optional adjustment device 6 for adjusting the diameter of the headband of the attachment device 13 for a particular wearer. In other configurations, the headband can be worn with an elastic headband, in which case , the adjustment device 6 may not be included.

The sliding promoter 4 is arranged radially inward from the energy absorbing layer 3 . The sliding facilitator 4 is adapted to slide against the energy absorbing layer or against the attachment means 13 provided for attaching the helmet to the wearer's head.

The sliding facilitator 4 is provided to assist the energy absorbing layer 3 to slide relative to the attachment means 13 in the same manner as discussed above. The sliding accelerator 4 may be made of a material with a low friction coefficient, or may be coated with this material.

Thus, in the helmet of FIG. 4 , the sliding promoter 4 can be arranged on the innermost side of the energy absorbing layer 3 facing the attachment means 13 or integrated with it.

However, it is also conceivable that the sliding facilitator 4 could be provided on an outer surface of the attachment means 13 or integrated therewith for the same purpose of providing slideability between the energy absorbing layer 3 and the attachment means 13 . That is, in certain configurations, the attachment device 13 itself may be adapted to act as a sliding facilitator 4 and may comprise a low friction material.

In other words, the sliding promoter 4 is arranged radially inward from the energy absorbing layer 3 . The sliding promoter may also be arranged radially outward from the attachment device 13 .

When the attachment means 13 is formed as a cap or mesh (as discussed above), the sliding promoter 4 can be provided as a patch of low friction material.

The low friction material can be a waxy polymer (such as PTFE, ABS, PVC, PC, Nylon, PFA, EEP, PE and UHMWPE) or a powder material that can be infused with lubricant. Low friction materials can be fabric materials. As discussed, this low friction material can be applied to either or both the slip promoter and the energy absorbing layer.

The attachment means 13 can be fixed to the energy absorbing layer 3 and/or the outer shell 2 by means of fastening means 5, such as the four fastening means 5a, 5b, 5c and 5d in Figure 4. These fixed parts can Adapted to absorb energy by deforming in an elastic, semi-elastic or plastic manner. However, this is not required. Furthermore, even where this feature is present, the amount of energy absorbed is generally minimal compared to the energy absorbed by the energy absorbing layer 3 during impact.

According to the configuration shown in Figure 4, the four fixed parts 5a, 5b, 5c and 5d are suspension parts 5a, 5b, 5c, 5d with first parts 8 and second parts 9, wherein the suspension parts 5a, 5b, 5c, The first part 8 of 5d is adapted to be fixed to the attachment means 13 and the second part 9 of the suspension parts 5a, 5b, 5c, 5d is adapted to be fixed to the energy absorbing layer 3.

Figure 5 shows the configuration of a helmet similar to that of Figure 4 when placed on the wearer's head. The helmet 1 of Figure 5 includes a hard shell 2 made of a different material than the energy absorbing layer 3. In comparison to Figure 4, in Figure 5 the attachment device 13 is fixed to the energy absorbing layer 3 by means of two fastening parts 5a, 5b adapted to absorb energy elastically, semi-elastically or plastically and force.

Figure 5 shows an oblique impact I before generating a rotational force on the helmet. The oblique impact I causes the energy absorbing layer 3 to slide relative to the attachment device 13 . The attachment means 13 are fixed to the energy absorbing layer 3 by means of fastening means 5a, 5b. Although for the sake of clarity only two such fixed components are shown, in practice there may be many such fixed components. The fixed component 5 can absorb rotational force by deforming elastically or semi-elastically. In other configurations, the deformation may be plastic or even lead to severing of one or more of the fixed components 5 . In the case of plastic deformation, after impact, at least the fixing part 5 will need to be replaced. In certain situations, a combination of plastic and elastic deformations in the fastening parts 5 may occur, ie some fastening parts 5 rupture, plastically absorbing energy, while other fastening parts deform elastically and absorb force.

Generally speaking, in the helmet of Figures 4 and 5, the energy absorbing layer 3 acts as an impact absorber during an impact by compressing in the same manner as the inner shell of the helmet of Figure 1 . like Using the outer shell 2 it will help spread the impact energy over the energy absorbing layer 3 . The slip promoter 4 will also allow sliding between the attachment means and the energy absorbing layer. This allows the energy that would otherwise be transmitted to the brain as rotational energy to be dissipated in a controlled manner. This energy can be dissipated by frictional heat, deformation of the energy absorbing layer, or deformation or displacement of the fixed component. Reduced rotational acceleration resulting from reduced energy transfer affects the brain, thereby reducing the rotation of the brain within the skull. The risk of rotational injuries including MTBI and STBI (such as subdural hematoma, SDH, vascular rupture, concussion and DAI) is thereby reduced.

The connectors that can be used inside the helmet are described below. It should be understood that these connectors can be used in a variety of content contexts and are not limited to use within helmets. For example, they may be used in other devices that provide impact protection, such as body armor or padding for athletic equipment. In the context of helmets, connectors may be used, in particular, to replace previously known connecting and/or fixing components of the arrangement discussed above.

In a configuration, the connector can be used with a helmet 1 of the type shown in Figure 6 . The helmet shown in Figure 6 has a configuration similar to that discussed above with respect to Figures 4 and 5. In particular, the helmet has a relatively hard outer shell 2 and an energy absorbing layer 3 . Head attachment means are provided in the form of a helmet liner 15 . Liner 15 may include comfort padding as discussed above. Generally speaking, the liner 15 and/or any comfort pad may not absorb a significant proportion of the energy of an impact compared to the energy absorbed by the energy absorbing layer 3 .

Lining 15 is removable. This may enable cleaning of the lining and/or may enable the deployment of a lining modified to fit a particular wearer.

Between the lining 15 and the energy absorbing layer 3, an inner shell 14 formed of a relatively hard material (that is, a material harder than the energy absorbing layer 3) is provided. Inner shell 14 may be molded to energy absorbing layer 3 and may be made from any of the materials discussed above in connection with forming outer shell 2 . in substitution In one configuration, the inner housing 14 may be formed from a fabric material, optionally coated with a low friction material.

In the configuration of Figure 6, a low friction interface is provided between the inner shell 14 and the liner 15. This may be implemented by appropriate selection of at least one of the material used to form the outer surface of the liner 15 or the material used to form the inner shell 14 . Alternatively or additionally, a low friction coating may be applied to at least one of the opposing surfaces of the inner shell 14 and liner 15 . Alternatively or additionally, lubricant may be applied to at least one of the opposing surfaces of the inner housing 14 and liner 15 .

As shown, liner 15 may be connected to the remainder of helmet 1 via one or more connectors 20 discussed in further detail below. The selection of the location of the connectors 20 and the number of connectors 20 to be used may depend on the configuration of the rest of the helmet.

In a configuration such as that shown in FIG. 6 , at least one connector 20 may be connected to the inner housing 14 . Alternatively or additionally, one or more of the connectors 20 may be connected to another part in the remainder of the helmet 1 , such as the energy absorbing layer 3 and/or the outer shell 2 . The connector 20 can also be connected to two or more parts in the rest of the helmet 1 .

Figure 7 shows another alternative configuration of the helmet 1. As shown, the helmet 1 of this configuration includes a plurality of separate sections of comfort pad 16 . Each section of comfort pad 16 may be connected to the remainder of the helmet by one or more connectors 20 .

The section of comfort pad 16 may have a sliding interface provided between the section of comfort pad 16 and the remainder of the helmet 1 . In this configuration, the sections of comfort pad 16 may provide similar functionality to that of liner 15 in the configuration shown in FIG. 6 . The options discussed above for creating a sliding interface between the liner and the helmet also apply to the sliding interface between sections of the comfort liner and the helmet.

It should also be understood that the configuration of Figure 7 (i.e., multiple independently mounted sections of comfort liner 16 having a sliding interface between sections of comfort liner 16 and the rest of the helmet) Can be combined with any form of helmet, including those such as those illustrated in Figures 1 to 5 that also have a sliding interface disposed between two other parts of the helmet.

Figures 8 and 9 show arrangements equivalent to those of Figures 6 and 7, except that the inner shell 14 is applied to the liner 15 (in Figure 8) or the comfort liner 16 (in Figure 9). In the case of Figure 9, the inner housing 14 may be only a part of the housing or a plurality of sections of the housing, as compared to the essentially full housing configuration of Figures 6-8. In fact, in both FIGS. 8 and 9 , the inner shell 14 may also be represented as a relatively hard coating on the lining 15 or comfort pad 16 . With regard to Figures 8 and 9, the inner shell 14 is formed from a relatively hard material (ie, a material harder than the energy absorbing layer 3). For example, the material can be PTFE, ABS, PVC, PC, Nylon, PFA, EEP, PE and UHMWPE. This material can be bonded to the outside of the liner 15 or comfort pad 16 to simplify the manufacturing process. This joining may be by any means, such as by adhesive or by high frequency welding or stitching. In an alternative configuration, the inner housing 14 may be formed from a fabric material, optionally coated with a low friction material.

In FIGS. 8 and 9 , a low friction interface is provided between the inner shell 14 and the energy absorbing layer 3 . This may be implemented by appropriate selection of at least one of the material used to form the outer surface of the energy absorbing layer 3 or the material used to form the inner shell 14 . Alternatively or additionally, a low friction coating may be applied to at least one of the opposing surfaces of the inner shell 14 and the energy absorbing layer 3 . Alternatively or additionally, lubricant may be applied to at least one of the opposing surfaces of the inner housing 14 and the energy absorbing layer 3 .

In FIGS. 8 and 9 , at least one connector 20 can be connected to the inner housing 14 . Alternatively or additionally, one or more of the connectors 20 may be connected to another component in the liner 15 or remainder of the comfort pad 16.

In another configuration, the connector may be used with a helmet 1 of the type shown in Figure 10. The helmet shown in Figure 10 has the same features as discussed above with respect to Figures 1, 2, 3A and 3B. It has a similar configuration. In particular, the helmet has a relatively hard outer shell 2 and an energy absorbing layer 3 configured to slide relative to each other. At least one connector 20 can be connected to the outer shell 2 and the energy absorbing layer 3 . Alternatively, the connector may be connected to one or more intermediate sliding layers providing low friction associated with one or both of the outer shell 2 and the energy absorbing layer 3 .

In yet another configuration, the connector may be used with a helmet 1 of the type shown in Figure 11. The helmet shown in Figure 11 has a similar configuration to that discussed above with respect to Figure 3B. In particular, the helmet has a relatively hard outer shell 2 and an energy absorbing layer 3 divided into an outer part 3A and an inner part 3B configured to slide relative to each other. At least one connector 20 can be connected to the outer part 3A and the inner part 3B of the energy absorbing layer 3 . Alternatively, the connector may be connected to one or more intermediate sliding layers providing low friction associated with one or both of the outer part 3A and the inner part 3B of the energy absorbing layer 3 .

Figure 12 shows yet another alternative configuration of the helmet 1. In this configuration, one or more outer panels 17 may be mounted to a helmet 1 having at least an energy absorbing layer 3 and a relatively stiff layer 2 formed outwardly from the energy absorbing layer 3 . It will be appreciated that this configuration of outer panels 17 can be added to any helmet according to any of the configurations discussed above (ie having a sliding interface between at least two of the layers of helmet 1).

The outer panel 17 may be mounted to the relatively hard layer 2 in such a way that, at least under impact to the outer panel 17, between the outer surface of the relatively hard layer 2 and the surface of the outer panel 17 in contact with the outer surface of the relatively hard layer 2 A low friction interface is provided between at least one portion. In some configurations, an intermediate low friction layer may be provided between hard layer 2 and plate 17 .

Furthermore, the outer panel 17 is mounted in such a way that upon impact to the outer panel 17 it can slide across the relatively hard layer 2 (or the intermediate low friction layer). Each outer panel 17 can be connected to the rest of the helmet 1 by one or more connectors 20 .

In this configuration, in the event of an impact on the helmet 1 , it is expected that the impact will fall on one or a limited number of outer panels 17 . Thus, by configuring the helmet such that one or more outer panels 17 can move relative to the relatively stiff layer 2 and any outer panels 17 that are not impacted, the surface that receives the impact (i.e., one or a limited number of outer panels 17 ) can be moved relative to the rest of the helmet 1 . This reduces the transfer of rotational forces to the rest of the helmet in the event of an oblique or tangential impact. In turn, this may reduce the rotational acceleration imparted to the brain of the wearer of the helmet and/or reduce brain damage.

13-15 show different views of the first example connector 20 according to the present invention. As explained above, the connector 20 is used to connect the inner and outer layers of a device such as a helmet.

The connector 20 includes: a first attachment part 21 for attaching the connector 20 to one of the inner layer or the outer layer; and a second attachment part 22 for attaching the connector 20 to the inner layer. The other of layer or outer layer. The first attachment part 21 and the second attachment part 22 are connected in a manner to allow the first attachment part and the second attachment part to move relative to each other when the inner and outer layers move relative to each other. In the example of the present invention, the first attachment part 21 and the second attachment part 22 are connected by an elastic component 23 . The characteristics of the first attachment part 21, the second attachment part 22 and the elastic component 23 will be explained in more detail below.

Figures 13 and 14 show the first attachment part 21 in more detail. As shown, the first attachment part 21 includes a first flange portion 211 . The first flange portion 211 is attached to the elastic member 23 by a neck portion 212 . As best shown in FIG. 14 , the neck portion 212 is bent at an angle of approximately 90 degrees such that the central axis through the first flange portion 211 is substantially perpendicular to the central axis through the elastic portion 23 .

The neck portion 212 means that although the attachment between the first attachment part 21 and the inner or outer layer of the device is carried out in a direction substantially perpendicular to the inner or outer layer of the device, the connection The container 20 itself extends substantially parallel to the inner or outer layer of the device, as shown in Figure 14.

The first attachment part 21 further includes a second flange portion 213 . As shown, these second flange portions may be disposed on neck portion 212. The first flange portion 211 and the second flange portion 213 may be configured to face each other and be separated by a gap 214 . As shown in FIG. 14 , gap 214 may be configured to receive a portion of one of the inner or outer layers to which first attachment feature 21 is connected and retain that portion within gap 214 . In some examples, portions of elastic member 23 may serve as a second flange portion. The example shown in Figure 14 is this example, although an additional second flange portion 213 is also provided. Therefore, the first flange portion 211 and the second flange portion 213 enable the first attachment part 21 to be fixed in position relative to an inner or outer layer of the device.

As shown in Figures 13-15, the first flange portion 211 may be substantially dome-shaped. It should be noted that the dome shape may have a circular outline as shown in the figure, but is not limited thereto. For example, the profile may alternatively be oval or elliptical. The term dome shape may refer to a substantially smooth, curved, convex shape. The bottom surface of the peripheral portion of the dome may face the second flange portion 213 across the gap 214 .

As shown in Figure 14, when the first attachment part 21 is connected to one of the inner or outer layers of the helmet such that the inner or outer layer remains within the gap between the flange portions 211 and 213, the first flange The domed shape of portion 211 creates a relatively streamlined configuration with a small profile. Preferably, the dome-shaped first flange portion 211 is substantially flat. For example, the dome-shaped first flange portion 211 may have a thickness of between 0.5 mm and 2 mm (eg, about 1 mm). The smoothness of the dome shape (ie, the lack of sharp corners) reduces the point pressure that would be felt if the first flange portion 211 were in contact with the wearer of the device. In addition, the dome shape can prevent the wearer's hair from being caught by the first attachment part 21 .

The second attachment part 22 includes a first portion 221 having a through hole 222 therein, such as Best shown in Figure 15. As shown in Figures 13 and 14, a second portion 223 (to which a fastening member may be attached) passes through the through hole 222 and is configured to attach to one of the inner or outer layers of the helmet. Preferably, the second part 223 is removable from the through hole 222 to be separated from the first part 221 . The first portion 221 may extend substantially in the same direction as the elastic member 23 connecting the first attachment part 21 and the second attachment part 22 . The through hole 222 may be disposed perpendicular to the extending direction of the first portion 221 . The through hole may also extend in a direction substantially parallel to the central axis passing through the first attachment part 21 .

As shown in Figure 14, the fastening member 223 may include a snap pin 224 configured to engage the snap basket 31 in the inner or outer layer of the device to which the second attachment part 22 is connected. As shown, the snap pin 224 can be connected to a flange portion 225 (eg, a plate) that is larger than the through hole 222 to retain the snap pin 224 within the through hole 222 . The second portion 223 may be formed of a relatively hard material compared to the first portion 221 . The orientation of the through hole 222 may mean that although the attachment between the second attachment feature 22 and the inner or outer layer of the device is in a direction substantially perpendicular to the inner or outer layer of the device, the connector 20 itself Extend substantially parallel to the inner or outer layer of the device, as shown in Figure 14.

As shown in Figure 15, the first portion 221 of the second attachment part 22 is configured so that the first portion 221 can be threaded through a hole 41 in an inner or outer layer of the device to which the first attachment part 21 is to be connected.

As shown in Figures 13-15, first portion 221 may have one or more substantially flat surfaces configured such that through holes 222 are formed in the surfaces.

Preferably, the thickness of the first part 221 (in the direction of the through hole 222) is relatively small compared with the width and length of the first part 221. Preferably, the width of the first part 221 should still not be greater than the length of the first part 221 . For example, the first portion 221 may be stretched in shape long, thus extending in a direction parallel to the elastic component 23 . The first portion 221 may be substantially rectangular in shape, as shown in the figures. However, other shapes may be used, such as oval or rectangular. These shapes may allow the first portion to spiral through hole 41 more easily.

In contrast, the first attachment part 21 is configured such that it cannot be screwed through the hole 41 . The hole 41 is configured to surround the neck portion 212 of the first attachment part 21 such that the edge of the hole 41 is located within the gap 214 between the first flange portion 211 and the second flange portion 213 .

Therefore, the width of the first flange portion 211 is greater than the width of the hole 41 . The difference between the width of the first flange portion 211 and the width of the hole 41 is preferably large enough so that the first flange portion 211 cannot be easily deformed to fit through the hole 41 .

Preferably, the second portion 223 of the second attachment part 22 is configured such that when located within the through hole 222 in the first portion 221 of the second attachment part 22, the second portion 223 cannot thread through the hole 41. In the case of the configuration set forth above, once the connector 20 is properly attached, it is difficult to detach.

As shown, the cross-sectional shape of first portion 221 may be substantially rectangular. The rectangular shape reduces the thickness of the first portion 221 while providing sufficient space for the through hole 222 . However, any shape can be used. As shown in FIG. 15 , the shape of the hole 41 may substantially correspond to the cross-sectional shape of the first portion 221 . However, this is not necessarily necessary.

The elastic member 23 may be configured to deform elastically, semi-elastically or plastically to allow the first attachment part 21 and the second attachment part 22 to move relative to each other. Therefore, the elastic member 23 may be formed from an elastic material, such as natural or synthetic rubber (eg silicone rubber), PP (polypropylene), PU (polyurethane) or the like, TPE (thermoplastic elastomer), or combinations and mixtures thereof. The elastic member 23 can be configured to flex in any direction. However, elastic components may be allowed 23 is configured to bend substantially only in planes parallel to the inner and outer layers of the device. The elastic member 23 may also be configured to stretch along its axis.

As shown in Figure 13, when the connector 20 is attached to the inner and outer layers, the elastic member 23 can be biased in a direction perpendicular to the plane of the inner and outer layers when in the neutral state. Thus, when the first attachment part 21 is attached to one of the inner or outer layers, the second attachment part 22 can be pressed against the inner or outer layer, as shown in Figure 14. Therefore, the elastic member 23 bends in a direction perpendicular to the central axis passing through the elastic member 23 . This configuration means that the connector 20 remains substantially parallel to the inner or outer layer to which the first attachment part 21 is connected during installation, thereby making it easier to connect the second attachment part 22 into the inner or outer layer. the other one.

The elastic portion 23 is preferably an elongated member, as shown in Figures 13-15. The cross-sectional shape of the elastic member 23 may be oval (as shown in the figure), circular, or any other shape. The elastic portion 23 has a cross-sectional shape such that it can be threaded through the hole 41 . The size of the elastic portion 23 should be such that it allows at least an amount of deformation required for the first attachment part 21 and the second attachment part 22 to move relative to each other, if desired. This may allow for example a displacement of between 5mm and 30mm or preferably 10mm to 15mm in any direction.

As shown in the figure, the first attachment part 21 may be formed from the same material as the elastic portion 23 . As shown in the figure, the first portion 221 of the second attachment part 22 may be formed of the same material as the elastic portion 23 . The elastic component 23 may be formed as one elastic component having the first portion 221 of the first attachment part 21 and/or the second attachment part 22 . Alternatively, the parts can be made from different materials that are attached or co-molded together.

Figures 16 to 19 show a second example connector 20 according to the present invention. The second example connector 20 includes a resilient portion 23 and a second attachment feature 22 that are substantially the same as those of the first example connector 20 . However, as shown in Figure 16, the first portion of the second attachment part 22 221 further includes an elongated tail 226 protruding therefrom. As shown, tail 226 extends substantially in the same direction as first portion 221 . Tail 226 is configured to assist in threading first portion 221 through hole 41 by providing a piece that can be more easily grasped and pulled through hole 41 .

As shown in FIG. 16 , this first attachment feature 21 is different from the first attachment feature 21 of the first example connector 20 . In the second example connector 20, the first attachment feature 21 includes separate first and second sections 215, 216 shown in Figures 17 and 18, respectively. The first section 215 includes a first flange portion 217 at a peripheral portion of the first section 215 . The first section 215 further includes a recessed portion 218 at a central portion of the first section 215 within the peripheral portion, and a through hole 219 passing through the recessed portion 218 .

The second section 216 of the first attachment feature 21 includes a flange portion 2110 configured to be located within the recessed portion 218 of the first section 215 and a through hole configured to pass through the first section 215 The neck part of 219 is 212. Neck portion 212 is connected to the remainder of connector 20 . Preferably, the first flange portion 217 of the first section 215 and the flange portion 2110 of the second section 216 together form a substantially flat continuous surface when located therein. In other words, the top surface of the first flange portion 217 of the first section 215 and the flange portion 2110 of the second section 216 may be substantially flush with each other. The flatness (ie, the lack of substantial undulations or corners) reduces the point pressure that would be felt if the surface of the first attachment feature 21 were in contact with the wearer of the device.

The first section 215 and the second section 216 of the first attachment part 21 may be configured by threading the remainder of the connector 20 through the through hole 219 until the flange portion 2110 is located in the recessed portion 218 Assemble together. Accordingly, the first portion 221 of the second attachment feature 22 may be sized and shaped to pass through the through hole 219 .

The first section 215 of the first attachment feature 21 may include a second flange portion 2112 , both of the second flange portion 2112 and the first flange portion 217 adjacent the gap 214 . gap 214 may be used to receive a portion of one of the inner or outer layers to which the first attachment feature 21 will be connected and to retain the inner or outer layer within the gap 214 . Alternatively, the second flange portion may be provided on the neck portion 212, or the elastic member 23 may act as the second flange portion.

The first section 215 of the first attachment part 21 may be made of a relatively hard material such as PP (polypropylene), PA (polyamide), POM (polyoxymethylene), PC (polycarbonate), wood or a material such as aluminum or steel metal) formed. However, neck portion 212 may be formed from an elastic material. For example, this material may be the same material from which elastic member 23 is formed. The elastic member 23 may be formed as one elastic member of the neck portion 212 of the first attachment part 21 . Alternatively, the parts can be made from different materials that are attached or co-molded together.

It will be appreciated that connectors 20 within the scope of the present invention may include first attachment parts 21 , second attachment parts 22 and/or elastic portions different from those set forth above. For example, a connector 20 within the scope of the present invention may comprise only one or only two parts selected from the first attachment part 21, the second attachment part 22 and the elastic part 23 explained above, where The remaining parts are different.

As set forth above, features of the inner and/or outer layers of the device may be configured to attach to the first and second attachment features 21 , 22 of the first and second example connectors 20 . For example, one of the inner or outer layers may include holes 41 for attaching the first attachment feature 21 . One of the inner or outer layers may include a mechanism for attaching the fastening members of the second attachment part 22 thereto, such as snap basket 31 .

In view of the above configuration, it may be preferable, but not necessary, for the holes 41 to be formed in a relatively thin layer. This may make it easier to attach the first attachment part 21 . In some examples, holes 41 may be formed in recessed portions of the layer. The recessed portion may be configured to receive the first attachment feature. This configuration may further help reduce the risk of first flange portion 211 coming into contact with the wearer of the device. The point pressure that will be felt may prevent the wearer's hair from being caught by the first attachment part 21 . Additionally, the edges of hole 41 may be rounded (eg, rather than squared). The rounded edge may be formed by the shape of the punching tool used to form the hole 41 . This feature can increase the life of the device by reducing wear between the hole 41 and the connector.

Similarly, it may be preferable if the means 31 for attaching fastening members are provided in a relatively thick layer. This may allow the mechanism 31 to be more securely fixed in this layer.

A preferred configuration of the device may be an outer layer of the energy absorbing layer 3 and an inner layer of the interface layer 13, such as the configuration shown in Figure 1 and explained above. Figures 14, 19, and 20 show example connectors 20 as part of a connection configuration within a device. Figure 14 shows the outer layer of the device, which is the energy absorbing layer 3. Figures 14, 19 and 20 show the inner layer of the device, which is the interface layer 13.

The assembly of a device according to the invention will now be explained with reference to Figures 14, 15, 19 and 20 and to a configuration in which the first attachment part 21 is connected to the interface layer 13 and the second attachment part is connected to the energy absorbing layer 3 method. As shown in part in FIG. 15 , the method includes spiraling the second attachment part 22 through the hole 41 in the interface layer 13 until the first attachment part 21 abuts the hole 41 . As shown in the close-ups in Figures 19 and 20, the first attachment part 21 is then attached to the interface layer at the hole 41 via the first flange portion 211, 217 and the second flange portion 213, 2112. This can be attached with a snap fit. As shown in Figure 14, the second attachment part 22 is attached to the energy absorbing layer 3, for example via a fastening member 223 and a corresponding mechanism 31.

The method may include the step of assembling the second attachment part 22 by positioning the fastening member 223 in the through hole 222 . This may be done after the step of passing the second attachment part 22 through the hole 41 . In the case of the second example connector 20 , the method may include the step of assembling the first attachment part 21 by positioning the second part 216 within the first part 215 . This can be done in the second The step of attaching the part 22 through the hole 41 is carried out before. Alternatively, this can be done after or during the step of passing the second attachment part 22 through the hole 41 . For example, the first portion 215 of the first attachment part 21 may be pre-attached to the interface layer, and then the second attachment part may be threaded through the first portion 215 of the first attachment part 21 and the hole 41 .

It will be appreciated that connector 20 may be used to connect any two parts of the device together (eg, any of the layers discussed above). Furthermore, where connector 20 is illustrated as connecting a first part to a first part of the device (eg, an interface layer) and a second part to a second part of the device (eg, an energy absorbing layer) , it should be understood that this can be reversed using suitable modifications.

Variations on the embodiments described above are possible in light of the above teachings. It is to be understood that the present invention may be practiced in other ways and in the manner specifically set forth herein without departing from the spirit and scope of the invention.

20:Connector/First instance connector/Second instance connector

21: First attachment part

22: Second attachment part

23: Elastic parts/elastic parts

211: First flange part/flange part/dome-shaped first flange part

212: Neck part

213: Second flange part/flange part

214:Gap

221:Part One

223:Part 2/Fastening components

224: snap pin

225:Flange part

Claims (11)

A protective helmet (1) comprising: an inner layer and an outer layer configured to move relative to each other; and at least one connector (20) connecting the inner layer and the outer layer, the connector (20) Comprising: a first attachment part (21) for attaching to the inner layer; a second attachment part (22) for attaching to the outer layer; wherein: the first attachment part ( 21) Connected to the second attachment part (22) in a manner that allows the first attachment part (21) and the second attachment part (22) to move relative to each other when the inner layer and the outer layer move relative to each other. move relative to each other, and the first attachment part (21) includes: a first flange portion (211) adjacent to a gap (214) for receiving a portion of the inner layer, the first The flange portion (211) holds the inner layer within the gap (214) and is characterized in that the inner layer is an interface layer configured to interface with the wearer's head; the first The flange portion (211) is substantially dome-shaped and substantially flat; the inner layer contains a hole (41) for the connector (20) to be screwed through the hole (41) so that the hole One edge of (41) is located within the gap (214), and the first attachment part (21) is configured so that the first attachment part (21) cannot be screwed through the hole (41) ). The protective helmet of claim 1, wherein the first flange portion (211) has a thickness of between 0.5 mm with a thickness between 2 mm. The protective helmet of claim 1 or 2, wherein in use, the first flange portion (211) is configured to exert point pressure on the wearer's head. The protective helmet of claim 1 or 2, wherein the connector (20) further includes an elastic component (23) connecting the first attachment part (21) and the second attachment part (twenty two). The protective helmet of claim 4, wherein the connector (20) further includes a neck portion (212) connecting the first flange portion (211) to the elastic member (23), wherein the neck portion (212) is bent at an angle of about 90 degrees, so that a central axis passing through the first flange part (211) is substantially perpendicular to a central axis passing through the elastic part (23). The protective helmet of claim 5, wherein the attachment between the first attachment part (21) and the second attachment part (22) is performed in a direction substantially perpendicular to the inner layer, and the The connectors (20) are substantially parallel to the inner layer. The protective helmet of claim 1 or 2, wherein the first attachment part (21) includes a second flange part (213), the second flange part (213) is disposed between the gap (214) and the The side opposite the first flange part (211). The protective helmet of claim 1 or 2, wherein the inner layer and the outer layer are configured to slide The interfaces move relative to each other. A protective helmet as claimed in claim 8, wherein the outer layer is an energy absorbing layer, and the protective helmet (1) includes a sliding accelerator (4) configured to slide against the outer layer or the inner layer . A protective helmet as claimed in claim 9, wherein the inner layer is the slip promoter (4) and is configured to slide against the energy absorbing layer. A method of assembling a protective helmet (1) according to any one of claims 1 to 10, comprising screwing a second attachment part (22) through a hole (41) in the inner layer until the A first attachment part (21) is adjacent to the hole (41); at the hole (41), the first attachment part (21) is attached to the inner layer via the first flange portion (211); and attaching the second attachment part (22) to the outer layer.