Connector with a deformable retainer

There is disclosed a connector for connecting first and second parts of an apparatus, the connector comprising: a deformable retainer having first and second sides around an inner space; and a first plate positioned within the inner space to provide a low friction interface between the first and second sides of the retainer; wherein the first side of the retainer has a first anchor point that is configured to connect the connector to the first part of the apparatus; and the second side of the retainer has a second anchor point that is configured to connect the connector to the second part of the apparatus.

RELATED APPLICATIONS

This application is a 35 USC § 371 National Stage application of International Application No. PCT/EP2019/080752, entitled “CONNECTOR,” filed on Nov. 8, 2019, which claims the benefit of United Kingdom Patent Application No. 1818219.6, filed on Nov. 8, 2018, the disclosure of which is incorporated herein by reference in its entirety.

The present invention relates to a connector, which may be used to connect two parts of an apparatus, for example for connecting a liner or comfort padding to the remainder of a helmet.

Helmets are known for use in various activities. These activities include combat and industrial purposes, such as protective helmets for soldiers and hard-hats or helmets used by builders, mine-workers, or operators of industrial machinery for example. Helmets are also common in sporting activities. For example, protective helmets may be used in ice hockey, cycling, motorcycling, motor-car racing, skiing, snow-boarding, skating, skateboarding, equestrian activities, American football, baseball, rugby, soccer, cricket, lacrosse, climbing, golf, airsoft and paintballing.

Helmets can be of fixed size or adjustable, to fit different sizes and shapes of head. In some types of helmet, e.g. commonly in ice-hockey helmets, the 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 a helmet with two or more parts which can move with respect to each other. In other cases, e.g. commonly in cycling helmets, the helmet is provided with an attachment device for fixing the helmet to the user's head, and it is the attachment device that can vary in dimension to fit the user's head whilst the main body or shell of the helmet remains the same size. In some cases, comfort padding within the helmet can act as the attachment device. The attachment device can also be provided in the form of a plurality of physically separate parts, for example a plurality of comfort pads which are not interconnected with each other. Such attachment devices for seating the helmet on a user's head may be used together with additional strapping (such as a chin strap) to further secure the helmet in place. Combinations of these adjustment mechanisms are also possible.

Helmets are often made of an outer shell, that is usually hard and made of a plastic or a composite material, and an energy absorbing layer called a liner. In other arrangements, such as a rugby scrum cap, a helmet may have no hard outer shell, and the helmet as a whole may be flexible. In any case, nowadays, a protective helmet has to be designed so as to satisfy certain legal requirements which relate to inter alia the maximum acceleration that may occur in the centre of gravity of the brain at a specified load. Typically, tests are performed, in which what is known as a dummy skull equipped with a helmet is subjected to a radial blow towards the head. This has resulted in modern helmets having good energy-absorption capacity in the case of blows radially against the skull. Progress has also been made (e.g. WO 2001/045526 and WO 2011/139224, which are both incorporated herein by reference, in their entireties) in developing helmets to lessen the energy transmitted from oblique blows (i.e. which combine both tangential and radial components), by absorbing or dissipating rotation energy and/or redirecting it into translational energy rather than rotational energy.

Such oblique impacts (in the absence of protection) result in both translational acceleration and angular acceleration of the brain. Angular acceleration causes the brain to rotate within the skull creating injuries on bodily elements connecting the brain to the skull and also to the brain itself.

Examples of rotational injuries include Mild Traumatic Brain Injuries (MTBI) such as concussion, and Severe Traumatic Brain Injuries (STBI) such as subdural haematomas (SDH), bleeding as a consequence of blood vessels rapturing, and diffuse axonal injuries (DAI), which can be summarized as nerve fibres being over stretched as a consequence of high shear deformations in the brain tissue.

Depending on the characteristics of the rotational force, such as the duration, amplitude and rate of increase, either concussion, SDH, DAI or a combination of these injuries can be suffered. Generally speaking, SDH occur in the case of accelerations of short duration and great amplitude, while DAI occur in the case of longer and more widespread acceleration loads.

In helmets such as those disclosed in WO 2001/045526 and WO 2011/139224 that may reduce the rotational energy transmitted to the brain caused by oblique impacts, the first and second parts of the helmet may be configured to slide relative to each other following an oblique impact. However, it remains desirable for the first and second parts to be connected such that the helmet retains its integrity during normal use, namely when not subject to an impact. It is therefore desirable to provide connectors that, whilst connecting first and second parts of a helmet together, permit movement of the first part relative to the second part under an impact. It is also desirable to provide connectors within a helmet that can be provided without substantially increasing the manufacturing costs and/or effort.

The connectors in WO 2017/157765 address some of issues mentioned above. However, they can be relatively fiddly and time-intensive to manufacture. The present invention aims to at least partially address this problem by providing an easy to manufacture connector that permits relative movement under impact.

According to a first aspect of the present invention, there is provided a connector for connecting first and second parts of an apparatus, the connector comprising: a deformable retainer having first and second sides around an inner space; and a first plate positioned within the inner space to provide a low friction interface between the first and second sides of the retainer; wherein the first side of the retainer has a first anchor point that is configured to connect the connector to the first part of the apparatus; and the second side of the retainer has a second anchor point that is configured to connect the connector to the second part of the apparatus. The provision of the plate between the sides of the deformable retainer creates a low friction interface that allows the sides to move relative to each and thus allow the first and second parts of an apparatus to move relative to each other.

Optionally, the connector further comprises a second plate positioned within the inner space, the first and second plate being configured to slide with respect to each other to provide the low friction interface between the first and second sides of the retainer.

Optionally, the retainer has an aperture, optionally a slit, for inserting the first plate. The aperture can be on a second side of the retainer.

Optionally, the second anchor point comprises a pair of arms extending outwards from opposite edges of the aperture. The arms can be integrally formed with the retainer. The he arms can be deformable. The arms can extend across the second side of the retainer. The arms can extend beyond the second side of the retainer. The connector can be configured to connect to the second part of the apparatus by passing the arms through an opening in the second part of the apparatus.

Optionally, the deformable retainer is at least partially formed from a deformable material. The deformable material can be substantially elastically deformable. The deformable material can be a silicone elastomer.

Optionally, the deformable retainer comprises a fastener positioned on the first side of the retainer as the first anchor point. The fastener can be formed from a relatively stiff hard compared to the deformable material.

Optionally, the first anchor point comprises space for applying adhesive.

Optionally, the first plate is not fixed to the retainer. The second plate may not be either.

Optionally, the first plate comprises a low friction material.

According to a second aspect of the invention, there is provided a liner for a helmet, comprising a connector according the first aspect.

Optionally, the first anchor point of the connector is configured to be connected to the helmet.

Optionally, the liner comprises comfort padding and optionally a layer of relatively hard material, compared to the comfort padding, provided more outwardly than the comfort padding.

According to a third aspect of the invention, there is provided a helmet, comprising a liner according to the second aspect.

Optionally, the liner is removable from the helmet.

According to a fourth aspect of the invention, there is provided a method of assembling a connector for connecting first and second parts of an apparatus, the method comprising: forming a deformable retainer having first and second sides around an inner space, a first anchor point that is configured to connect a first side of the connector to the first part of the apparatus, and a second anchor point that is configured to connect the second side of the connector to the second part of the apparatus; and positioning a first plate within the inner space to provide a low friction interface between the first and second sides of the retainer.

Optionally, the connector is the connector of the first aspect.

The proportions of the thicknesses of the various layers in the helmets depicted in the figures have been exaggerated in the drawings for the sake of clarity and can of course be adapted according to need and requirements.

FIG.1depicts a first helmet1of the sort discussed in WO 01/45526, intended for providing protection against oblique impacts. This type of helmet could be any of the types of helmet discussed above.

Protective helmet1is constructed with an outer shell2and, arranged inside the outer shell2, an inner shell3that is intended for contact with the head of the wearer.

Arranged between the outer shell2and the inner shell3is a sliding layer4or a sliding facilitator, and thus makes possible displacement between the outer shell2and the inner shell3. In particular, as discussed below, a sliding layer4or sliding facilitator may be configured such that sliding may occur between two parts during an impact. For example, it may be configured to enable sliding under forces associated with an impact on the helmet1that is expected to be survivable for the wearer of the helmet1. In some arrangements, it may be desirable to configure the sliding layer or sliding facilitator such that the coefficient of friction is between 0.001 and 0.3 and/or below 0.15.

Arranged in the edge portion of the helmet1, in theFIG.1depiction, may be one or more connecting members5which interconnect the outer shell2and the inner shell3. In some arrangements, the connecting members5may counteract mutual displacement between the outer shell2and the inner shell3by absorbing energy. However, this is not essential. Further, even where this feature is present, the amount of energy absorbed is usually minimal in comparison to the energy absorbed by the inner shell3during an impact. In other arrangements, connecting members5may not be present at all.

Further, the location of these connecting members5can be varied (for example, being positioned away from the edge portion, and connecting the outer shell2and the inner shell3through the sliding layer4).

The outer shell2is preferably relatively thin and strong so as to withstand impact of various types. The outer shell2could be made of a polymer material such as polycarbonate (PC), polyvinylchloride (PVC) or acrylonitrile butadiene styrene (ABS) for example. Advantageously, the polymer material can be fibre-reinforced, using materials such as glass-fibre, Aramid, Twaron, carbon-fibre or Kevlar.

The inner shell3is considerably thicker and acts as an energy absorbing layer. As such, it is capable of damping or absorbing impacts against the head. It can advantageously be made of foam material like expanded polystyrene (EPS), expanded polypropylene (EPP), expanded polyurethane (EPU), vinyl nitrile foam; or other materials forming a honeycomb-like structure, for example; or strain rate sensitive foams such as marketed under the brand-names Poron™ and D3O™. The construction can be varied in different ways, which emerge below, with, for example, a number of layers of different materials.

Inner shell3is designed for absorbing the energy of an impact. Other elements of the helmet1will absorb that energy to a limited extend (e.g. the hard outer shell2or so-called ‘comfort padding’ provided within the inner shell3), but that is not their primary purpose and their contribution to the energy absorption is minimal compared to the energy absorption of the inner shell3. Indeed, although some other elements such as comfort padding may be made of ‘compressible’ materials, and as such considered as ‘energy absorbing’ in other contexts, it is well recognised in the field of helmets that compressible materials are not necessarily ‘energy absorbing’ in the sense of absorbing a meaningful amount of energy during an impact, for the purposes of reducing the harm to the wearer of the helmet.

A number of different materials and embodiments can be used as the sliding layer4or sliding facilitator, for example oil, Teflon, microspheres, air, rubber, polycarbonate (PC), a fabric material such as felt, etc. Such a layer may have a thickness of roughly 0.1-5 mm, but other thicknesses can also be used, depending on the material selected and the performance desired. The number of sliding layers and their positioning can also be varied, and an example of this is discussed below (with reference toFIG.3B).

As connecting members5, use can be made of, for example, deformable strips of plastic or metal which are anchored in the outer shell and the inner shell in a suitable manner.

FIG.2shows the functioning principle of protective helmet1, in which the helmet1and a skull10of a wearer are assumed to be semi-cylindrical, with the skull10being mounted on a longitudinal axis11. Torsional force and torque are transmitted to the skull10when the helmet1is subjected to an oblique impact K. The impact force K gives rise to both a tangential force KT and a radial force KR against the protective helmet1. In this particular context, only the helmet-rotating tangential force KT and its effect are of interest.

As can be seen, the force K gives rise to a displacement12of the outer shell2relative to the inner shell3, the connecting members5being deformed. A reduction in the torsional force transmitted to the skull10of roughly 25% can be obtained with such an arrangement. This is a result of the sliding motion between the inner shell3and the outer shell2reducing the amount of energy which is transferred into radial acceleration.

Sliding motion can also occur in the circumferential direction of the protective helmet1, although this is not depicted. This can be as a consequence of circumferential angular rotation between the outer shell2and the inner shell3(i.e. during an impact the outer shell2can be rotated by a circumferential angle relative to the inner shell3).

Other arrangements of the protective helmet1are also possible. A few possible variants are shown inFIG.3. InFIG.3a, the inner shell3is constructed from a relatively thin outer layer3″ and a relatively thick inner layer3′. The outer layer3″ is preferably harder than the inner layer3′, to help facilitate the sliding with respect to outer shell2. InFIG.3b, the inner shell3is constructed in the same manner as inFIG.3a. In this case, however, there are two sliding layers4, between which there is an intermediate shell6. The two sliding layers4can, if so desired, be embodied differently and made of different materials. One possibility, for example, is to have lower friction in the outer sliding layer than in the inner. InFIG.3c, the outer shell2is embodied differently to previously. In this case, a harder outer layer2″ covers a softer inner layer2′. The inner layer2′ may, for example, be the same material as the inner shell3.

FIG.4depicts a second helmet1of the sort discussed in WO 2011/139224, which is also intended for providing protection against oblique impacts. This type of helmet could also be any of the types of helmet discussed above.

InFIG.4, helmet1comprises an energy absorbing layer3, similar to the inner shell3of the helmet ofFIG.1. The outer surface of the energy absorbing layer3may be provided from the same material as the energy absorbing layer3(i.e. there may be no additional outer shell), or the outer surface could be a rigid shell2(seeFIG.5) equivalent to the outer shell2of the helmet shown inFIG.1. In that case, the rigid shell2may be made from a different material than the energy absorbing layer3. The helmet1ofFIG.4has a plurality of vents7, which are optional, extending through both the energy absorbing layer3and the outer shell2, thereby allowing airflow through the helmet1.

An attachment device13is provided, for attachment of the helmet1to a wearer's head. As previously discussed, this may be desirable when energy absorbing layer3and rigid shell2cannot be adjusted in size, as it allows for the different size heads to be accommodated by adjusting the size of the attachment device13. The attachment device13could be made of an elastic or semi-elastic polymer material, such as PC, ABS, PVC or PTFE, or a natural fibre material such as cotton cloth. For example, a cap of textile or a net could form the attachment device13.

Although the attachment device13is shown as comprising a headband portion with further strap portions extending from the front, back, left and right sides, the particular configuration of the attachment device13can vary according to the configuration of the helmet. In some cases the attachment device may be more like a continuous (shaped) sheet, perhaps with holes or gaps, e.g. corresponding to the positions of vents7, to allow air-flow through the helmet.

FIG.4also depicts an optional adjustment device6for adjusting the diameter of the head band of the attachment device13for the particular wearer. In other arrangements, the head band could be an elastic head band in which case the adjustment device6could be excluded.

A sliding facilitator4is provided radially inwards of the energy absorbing layer3. The sliding facilitator4is adapted to slide against the energy absorbing layer or against the attachment device13that is provided for attaching the helmet to a wearer's head.

The sliding facilitator4is provided to assist sliding of the energy absorbing layer3in relation to an attachment device13, in the same manner as discussed above. The sliding facilitator4may be a material having a low coefficient of friction, or may be coated with such a material.

As such, in theFIG.4helmet, the sliding facilitator may be provided on or integrated with the innermost sided of the energy absorbing layer3, facing the attachment device13.

However, it is equally conceivable that the sliding facilitator4may be provided on or integrated with the outer surface of the attachment device13, for the same purpose of providing slidability between the energy absorbing layer3and the attachment device13. That is, in particular arrangements, the attachment device13itself can be adapted to act as a sliding facilitator5and may comprise a low friction material.

In other words, the sliding facilitator4is provided radially inwards of the energy absorbing layer3. The sliding facilitator can also be provided radially outwards of the attachment device13.

When the attachment device13is formed as a cap or net (as discussed above), sliding facilitators4may be provided as patches of low friction material.

The low friction material may be a waxy polymer, such as PTFE, ABS, PVC, PC, Nylon, PFA, FEP, PE and UHMWPE, or a powder material which could be infused with a lubricant. The low friction material could be a fabric material. As discussed, this low friction material could be applied to either one, or both of the sliding facilitator and the energy absorbing layer.

The attachment device13can be fixed to the energy absorbing layer3and/or the outer shell2by means of fixing members5, such as the four fixing members5a,5b,5cand5dinFIG.4. These may be adapted to absorb energy by deforming in an elastic, semi-elastic or plastic way. However, this is not essential. Further, even where this feature is present, the amount of energy absorbed is usually minimal in comparison to the energy absorbed by the energy absorbing layer3during an impact.

According to the embodiment shown inFIG.4the four fixing members5a,5b,5cand5dare suspension members5a,5b,5c,5d, having first and second portions8,9, wherein the first portions8of the suspension members5a,5b,5c,5dare adapted to be fixed to the attachment device13, and the second portions9of the suspension members5a,5b,5c,5dare adapted to be fixed to the energy absorbing layer3.

FIG.5shows an embodiment of a helmet similar to the helmet inFIG.4, when placed on a wearers' head. The helmet1ofFIG.5comprises a hard outer shell2made from a different material than the energy absorbing layer3. In contrast toFIG.4, inFIG.5the attachment device13is fixed to the energy absorbing layer3by means of two fixing members5a,5b, which are adapted to absorb energy and forces elastically, semi-elastically or plastically.

A frontal oblique impact I creating a rotational force to the helmet is shown inFIG.5. The oblique impact I causes the energy absorbing layer3to slide in relation to the attachment device13. The attachment device13is fixed to the energy absorbing layer3by means of the fixing members5a,5b. Although only two such fixing members are shown, for the sake of clarity, in practice many such fixing members may be present. The fixing members5can absorb the rotational forces by deforming elastically or semi-elastically. In other arrangements, the deformation may be plastic, even resulting in the severing of one or more of the fixing members5. In the case of plastic deformation, at least the fixing members5will need to be replaced after an impact. In some case a combination of plastic and elastic deformation in the fixing members5may occur, i.e. some fixing members5rupture, absorbing energy plastically, whilst other fixing members deform and absorb forces elastically.

In general, in the helmets ofFIG.4andFIG.5, during an impact the energy absorbing layer3acts as an impact absorber by compressing, in the same way as the inner shell of theFIG.1helmet. If an outer shell2is used, it will help spread out the impact energy over the energy absorbing layer3. The sliding facilitator4will also allow sliding between the attachment device and the energy absorbing layer. This allows for a controlled way to dissipate energy that would otherwise be transmitted as rotational energy to the brain. The energy can be dissipated by friction heat, energy absorbing layer deformation or deformation or displacement of the fixing members. The reduced energy transmission results in reduced rotational acceleration affecting the brain, thus reducing the rotation of the brain within the skull. The risk of rotational injuries including MTBI and STBI such as subdural haematomas, SDH, blood vessel rapturing, concussions and DAI is thereby reduced.

Connectors of the present invention for connecting two parts of an apparatus are described below. It should be appreciated that these connectors may be used in a variety of contexts and are not be limited to use within helmets. For example, they may be used in other devices that provide impact protection, such as body armour or padding for sports equipment. In the context of helmets, the connectors of the present invention may, in particular, be used in place of the previously known connecting members and/or fixing members of the arrangements discussed above.

In an embodiment of the invention, the connector may be used with a helmet1of the type shown inFIG.6. The helmet shown inFIG.6has a similar configuration to that discussed above in respect ofFIGS.4and5. In particular, the helmet has a relatively hard outer shell2and an energy absorbing layer3. A head attachment device is provided in the form of a helmet liner15. The liner15may include comfort padding as discussed above. In general, the liner15and/or any comfort padding may not absorb a significant proportion of the energy of an impact in comparison with the energy absorbed by the energy absorbing layer3.

The liner15may be removable. This may enable the liner to be cleaned and/or may enable the provision of liners that are modified to fit a specific wearer.

Between the liner15and the energy absorbing layer3, there is provided an inner shell14formed from a relatively hard material, namely a material that is harder than the energy absorbing layer3. The inner shell14may be moulded to the energy absorbing layer3and may be made from any of the materials discussed above in connection with the formation of the outer shell2.

In the arrangement ofFIG.6, a low friction interface is provided between the inner shell14and the liner15. This may be implemented by the appropriate selection of at least one of the material used to form the outer surface of the liner15or the material used to form the inner shell14. Alternatively or additionally, a low friction coating may be applied to at least one of the opposing surfaces of the inner shell14and the liner15. Alternatively or additionally, a lubricant may be applied to at least one of the opposing surfaces of the inner shell14and the liner15.

As shown, the liner15may be connected to the remainder of the helmet1by way of one or more connectors20of the present invention, discussed in further detail below. Selection of the location of the connectors20and the number of connectors20to use may depend upon the configuration of the remainder of the helmet. Accordingly, the present invention is not limited to the configuration depicted inFIG.6.

In an arrangement such as shown inFIG.6, at least one connector20may be connected to the inner shell14. Alternatively or additionally, one or more of the connectors20may be connected to another part of the remainder of the helmet1, such as the energy absorbing layer3and/or the outer shell2. The connectors20may also be connected to two or more parts of the remainder of the helmet1.

FIG.7depicts a further alternative arrangement of a helmet1using the connectors20of the present invention. As shown, the helmet1of this arrangement includes a plurality of independent sections of comfort padding16. Each section of comfort padding16may be connected to the remainder of the helmet by one or more connectors20according to the present invention.

The sections of comfort padding16may have a sliding interface provided between the sections of comfort padding16and the remainder of the helmet1. In such an arrangement, the sections of comfort padding16may provide a similar function to that of the liner15of the arrangement shown inFIG.6. The options discussed above for provision of a sliding interface between a liner and a helmet also apply to the sliding interface between the sections of comfort padding and the helmet.

It should also be appreciated that the arrangement ofFIG.7, namely the provision of a plurality of independently mounted sections of comfort padding16provided with a sliding interface between the sections of comfort padding16and the remainder of the helmet may be combined with any form of helmet, including those such as depicted inFIGS.1to5that also have a sliding interface provided between two other parts of the helmet.

FIGS.8and9show equivalent embodiments to those ofFIGS.6and7, except that the inner shell14is applied to the liner15(inFIG.8) or comfort padding16(inFIG.9). In the case ofFIG.9, the inner shell14may only be a partial shell or a plurality of sections of shell, as compared to the substantially full shell arrangements ofFIGS.6to8. Indeed, in bothFIGS.8and9the inner shell14may also be characterised as a relatively hard coating on the liner15or comfort padding16. As forFIGS.6and7, the inner shell14is formed from a relatively hard material, namely a material that is harder than the energy absorbing layer3. For example, the material could be PTFE, ABS, PVC, PC, Nylon, PFA, FEP, PE and UHMWPE. The material may be bonded to the outer side of the liner15or comfort padding16to simplify the manufacturing process. Such bonding could be through any means, such as by adhesive or by high frequency welding.

InFIGS.8and9a low friction interface is provided between the inner shell14and the energy absorbing layer3. This may be implemented by the appropriate selection of at least one of the material used to form the outer surface of the energy absorbing layer3or the material used to form the inner shell14. Alternatively or additionally, a low friction coating may be applied to at least one of the opposing surfaces of the inner shell14and the energy absorbing layer3. Alternatively or additionally, a lubricant may be applied to at least one of the opposing surfaces of the inner shell14and the energy absorbing layer3.

InFIGS.8and9, at least one connector20may be connected to the inner shell14. Alternatively or additionally, one or more of the connectors20may be connected to another part of the remainder of the liner15or comfort padding16.

Connectors20according to the present invention will now be described. For convenience, the connectors20will be described in the context of a connector for connecting a liner15to the remainder of a helmet1as depicted inFIG.8. However, it should be appreciated that the connector20of the present invention may be used for connecting any two parts of an apparatus together. Furthermore, where below the connector20is described as having a first component connected to a first part of an apparatus, such as a helmet liner15, and a second component connected to a second part of an apparatus, such as the remainder of the helmet1, it should be appreciated that, with suitable modifications, this may be reversed.

FIG.10shows a perspective view of a connector20. The connector20is for connecting first and second parts of an apparatus, for example connecting an energy absorbing layer3of a helmet to an inner shell14/liner15combination as depicted inFIG.8.

The connector20has a deformable retainer21. The deformable retainer21has first and second sides22,23around an inner space24. As such, the deformable retainer21forms a pouch or pocket surrounding the inner space24. However, the inner space24need not be entirely enclosed or surrounded by the deformable retainer21. As shown inFIG.12, the retainer21may have cutaway sections exposing the inner space24. As discussed later, one or more plates25,26may be provided within the inner space24. As shown inFIG.11, these plates may protrude out of the inner space24and out of the deformable retainer21, through the cutaway sections. However, as also shown inFIG.11, at least a portion of the periphery of retain21is not cutaway in order to retain the plates25,26within the retainer21. In other words, at least several points around the perimeter of the retainer21, as illustrated inFIG.11, wrap around the outer edge of the plates25,26. In some arrangements, the entire outer edge of the plates may be covered by the retainer21, rather than just parts as shown inFIG.11.

The first and second sides22,23of the retainer21are each provided with an anchor point to connect the connector20to the first and second parts of the apparatus respectively. That is, the first side22of the retainer21has a first anchor point27. In other words, the body of the retainer21itself comprises the anchor point27. The anchor point27is not, for example, part of the plates25,26positioned within the inner space24defined by the retainer21. The first anchor point27is configured to connect the connector20to the first part of the apparatus. Similarly, the second side of the retainer21has a second anchor point28. The second anchor point28is configured to connect the connector20to the second part of the apparatus.

A particular example of a second anchor point28is discussed in more detail below, however a first anchor point27is simply depicted inFIG.12in the form of a blank space. Such a blank space could be used to apply an adhesive to fix the connector to the first part of the apparatus to be connected, for example. Alternatively, this area could be used to provide one side of a hook and loop connector (the other side being on the part to be connected to). The area could also be used for providing other methods of attachment, as befits the particular application for which the connector20is being used, such as for high frequency welding or providing part of a magnetic connector.

As such, the first anchor point27(and, indeed, the second anchor point28) can be used for permanent or releasable connection to the first part (or second part, in respect of the second anchor point28), as necessary. Either type of attachment (detachable or permanent) may be configured such that it prevents translational movement of a respective anchor point27,28relative to the part being connected to. However, anchor points27,28may be configured to allow rotation (e.g. in the case of a snap fitting) about one or more axes of rotation relative to the part being connected to. The anchor points27,28may also be connected to the parts to be connected by way of one or more additional components.

FIG.14shows an alternative first anchor point27in the form of a fastener. In particular, the anchor point forms one half of a snap-fit connection, the other half being in first part40being connected by the connector20. As illustrated, the fastener itself may be incorporated into the body of the retainer21. In other words, the fastener is part of the body of the retainer21.

In general, the deformable retainer21is at least partially formed from a deformable material. However, as in the embodiment ofFIG.14, the deformable retainer21need not be entirely made of deformable material. As such, the base of the fastener/anchor point27may be made of a relatively stiff material compared to the rest of the body of the retainer21. The deformable material used for the body of the retainer21may be, for example, an elasticated fabric, cloth or textile, or an elastomeric material. In particular, the deformable material may be a silicone or polysiloxane elastomer. In general, the deformable material is preferably substantially elastically deformable.

As indicated by the dashed lines inFIG.11, and shown in the cross-sectional views ofFIG.13andFIG.14, the connector can also include one or more plates25,26. The one or more plates25,26can be positioned within the inner space24of the retainer21. The one or more plates25,26provide a low friction interface between the first and second sides22,23of the retainer21. That is, the retainer21may deform to allow the first and second sides22,23to move relative to each other, and the low friction interface can facilitate that movement.

As such a connector20of the present invention may be configured to permit a desired relative range of movement between the first and second sides22,23, and therefore the relative range of movement between the first part of the apparatus the second part of the apparatus being connected. Such configuration may be achieved by the selection of the material forming the retainer21and the thickness of the material forming the retainer21, for example. A connector20for use within a helmet may be configured to enable a relative movement of the first and second sides22,23of the retainer21of approximately 5 mm or more in any direction within a plane parallel to the sliding interface.

The plates25,26used in the connector20may be made from a variety of different materials. In an example, a plate may be made from polycarbonate (PC), polyvinylchloride (PVC), acrylonitrile butadiene styrene (ABS), polypropylene (PP), nylon or another plastic. The plates may optionally have a thickness in the range of from approximately 0.1 mm to approximately 2 mm, optionally 0.2 mm to approximately 1.5 mm, for example approximately 0.7 mm thick.

Providing a first plate25within the inner space24allows the first side22of the retainer21and/or the second side of the retainer21to slide with respect to the plate, and thus with respect to each other. That is, the plate provides a low friction interface between the (internal) first and second sides22,23of the retainer21.

Alternatively, first and second plates25,26can be positioned within the inner space21. This is shown inFIGS.13and14, for example. This provides potential not only for the plates25,26to slide with respect to the inner surfaces of the retainer21, but also or alternatively with respect to each other. In other words, in this arrangement, there can be a low friction interface between the first and second plates25,26and as such there is a low friction interface between the first and second sides22,23of the retainer21.

In this context, a low friction interface may be configured such that sliding contact across the interface is still possible even under the loading that may be expected in use. In the context of a helmet, for example, it may be desirable for sliding to be maintained in the event of an impact that is expected to be survivable for the wearer of a helmet. This may be provided, for example, by the provision of an interface between the two surfaces at which the coefficient of friction is between 0.0001 and 0.3 and/or below 0.15.

The low friction interface may be implemented by at least one of: using a low friction material for the construction of the first and/or second sides22,23of the retainer21; applying a low friction coating to the inner surfaces of the first and second sides22,23; using a low friction material for at least one of the plates25,26; applying a low friction coating to at least one surfaces of the plates25,26; applying a lubricant to any of the structures inside of or forming the inner space24.

As such, the retainer21is not necessarily directly attached or bonded to the plates25,26, although in some embodiments such attachment may be present. Instead, the retainer21can be provided as a close enough fit around the plates25,26such that it stays in place due to the mechanical interaction with the plates25,26. Indeed, to initially fit the plates25,26within the retainer21, it may be necessary to stretch the retainer21and/or bend the plates25,26. An example of this is discussed in more detail below.

When viewed in plan view, the anchor points27,28may be arranged substantially at the centre of their respective sides22,23of the retainer21. However, the present invention is not limited to a particular configuration. When viewed in plan view, any convenient shape of the retainer21and plates25,26may be used, for example substantially rectangular, substantially square, substantially circular or substantially elliptical. In the case of a shape having corners, the corners may be rounded in order to minimise the risk of a plate getting caught on another part of the connector or another component.

As can be seen in the Figures, the connector20has an aperture29in the retainer21. The aperture29is a slit in the depicted embodiments, but any suitable shape could be used.

The aperture29allows the insertion of the plates25,26into the inner space of the retainer21. Because the retainer21is deformable, the aperture29need not be as large as the plates25,26. For example, as shown inFIG.11, the diameter of the depicted plate25is larger than the width of the slit29. However, the plate25can be inserted into the inner space24of the retainer21through the slit29, because the slit29and the retainer21can deform to allow the entry of the plate25. Providing a slit29that is not as large as the diameter of the plate25also has the advantage that the plate25is held securely within the retainer once the retainer21is allowed to return to its original shape

As shown in the Figures, the slit can be provided on the second side23of the retainer21, but could also be provided elsewhere.

The second anchor point28may be of any of the types discussed in connection with the first anchor point27, above. However, in the Figures a particular version of the second anchor point28is depicted. The second anchor point28on the second side23of the retainer21is depicted in the drawings as comprising a pair of arms30. The arms30extend across the second side23of the retainer21. The arms30can also extend beyond the second side23of the retainer21, as shown. That is, the length between the two ends of the arms30is longer than the width of the retainer21.

The arms30are integrally formed with the retainer21, in the embodiments depicted. That is, for example, the arms30could be moulded with the retainer21as part of a single moulding process.

The arms30are preferably deformable. As such, the arms30may be made from the same substantially elastically deformable materials as discussed above in connection with the material suitable for use for the retainer21.

The arms30may be attached to the second side23of the retainer21via a stem32. Stem32also forms part of the second anchor point28. The stem32is optionally made of the same material as the arms30. The stem32can provide a space between the arms and the second side23of the retainer21, to allow the arms to easily fit around a second part50as illustrated inFIG.12, and discussed below.

The arms30can be used to manipulate the connector, in particular whilst the connector20is being constructed. As such, each arm30may comprise a handle31provided at end of the arm, to assist with manipulating the connector. For example, when any plates25,26are being inserted into the inner space24of the retainer21, the connector20can be held by the arms30. Because the arms30are connected to the second side23of the retainer21, the arms can also be used to stretch the aperture29, to assist with inserting the plates25,26. That is, the arms30can be positioned such that they are separated by the aperture29. Therefore, pulling the arms30away from each other will tend to deform the aperture29to widen the access through the aperture29into the inner space24.

Also, as part of the anchor point28, the arms30enable the connector20to be connected to a layer of material such as the inner shell14or liner15, i.e. the second part50that the connector20is being connected to.FIG.12illustrates how the arms can be used to connect through and around a hole in a second part50. Because the arms30are deformable, they can be fed through a hole in a second part50, which hole can be smaller than the size of the retainer21. Once the arms30are fed through the hole in the second part50, the arms can spread out either side of the hole, extending in a direction that would be across the second side of the retainer21(although the arms30are separated from that second side23by the presence of the second part50). As such, the connector20is then connected to the second part50by the physical interlocking of the retainer21and the arms30around the second part50.

In other words, the retainer21and the arms30can extend on different sides of the second part50beyond the hole through the second part50, with the stem32positioned within the hole in second part50. The connector20is thus connected to the second part50via the second anchor point28. It is then difficult to remove the connector20without deliberately intending to do so. To further reinforce the attachment of the connector20to the second part50, or for aesthetic reasons, it may be desirable to place an adhesive patch or sticker on the second part50over the arms30, once they have been inserted through the hole in the second part50. However, this is not necessary to achieve the connecting function.

As mentioned above, the arms30and stem32may be formed as a single piece with the retainer21, by moulding for example. However, the connector may be formed by connecting together multiple pieces, e.g. either side of the inner space24, subsequently joined at the edges.

The preceding discussion has primarily considered the connector20shown inFIGS.10-14in isolation or in general use. However, as will be understood from the earlier description, such a connector20may be of specific use in helmets, where it is desirable for two parts to be able to move with respect to each other whilst also being connected. For example, the connector20could be arranged to have the arms30positioned through a hole in a helmet liner, with the other side (i.e. the first side22and anchor point27) arranged to connect to the inside of the helmet (e.g. an inner energy absorbing layer3). Such a liner may comprise comfort padding and/or a layer of relatively hard material, such as the inner shell14. In use, when such a connected liner/helmet arrangement is worn by a user, the connector20will allow for the liner to slide with respect to the helmet, by virtue of the first and second sides22,23moving with respect to the low friction interface between then.

Advantageously, a liner for a helmet may be provided pre-connected to the connectors20, leaving the first side22and associated first anchor point27free for connection to the helmet.