EP4401597A1

EP4401597A1 - A retention system for a helmet

Info

Publication number: EP4401597A1
Application number: EP22785995.6A
Authority: EP
Inventors: Fé VAN DAM; Ruben BROEKHUIZEN
Original assignee: Lazer Sport NV
Current assignee: Lazer Sport NV
Priority date: 2021-09-15
Filing date: 2022-09-14
Publication date: 2024-07-24
Also published as: BE1029757B1; BE1029757A1; WO2023041600A1

Abstract

A retention system (400) for a helmet comprising a head basket (300) that is attachable to an inner surface of the helmet, configured to enclose at least part of a wearer's head. The retention system further comprising an adjustment system (200), configured to adjust the head basket along the wearer's head. The adjustment system comprising an operating element, configured to allow operation of the adjustment system, wherein the operating element includes an endless band (201).

Description

A RETENTION SYSTEM FOR A HELMET

Field of the Invention

[01] The present invention generally relates to a retention system for a helmet, as well as to a helmet including said retention system, and a method of adjustment of said helmet including said retention system.

Background of the Invention

[02] A retention system for a helmet generally prevents the helmet from shifting on a wearer's head while being worn during dynamic activities such as sports, and/or when the helmet does not perfectly fit a wearer's head. This may be achieved by providing an adjustable fit along a circumference of the wearer's head. Common helmet retention systems comprise at least a head basket, at least partially enclosing the wearer's head, and an adjustment system, configured to tighten said head basket along the wearer's head.

[03] The adjustment system, often located at the rear of the head, commonly comprises a ratcheting mechanism to adjust the fit of the retention system. Operation of the adjustment system may be performed through an operating element, e.g. by turning a wheel or knob, thereby tightening or loosening the head basket. One problem with these retention systems is the position of the adjustment system and/or operating element, as they can obstruct a comfortable fit for users with a specific hairstyle, e.g. hair that is tied-back in a ponytail, and can obstruct air flow by protruding from the helmet, i.e. reduce the aerodynamics of helmets including said retention systems.

[04] Existing solutions that partially address these challenges include self-adjusting retention systems, which automatically tighten around a wearer's head by means of a pre-tensioned element and thus have no need for a protruding operating element. However, these solutions may lack a degree of adjustability desired by advanced athletes and/or common users. [05] Alternative solutions include retention systems with an adjustment system and/or operating element that can be partially integrated in the helmet body. A problem with these systems is that the adjustment system and/or operating element, e.g. a knob, a wheel, a thumbwheel, or a wedge, still protrude at least partially from the helmet body, thereby obstructing airflow around the helmet. Furthermore, these systems can be relatively difficult and/or impractical to operate due to the limited exposed operating surface of the operating element.

Summary of the Invention

[06] It is an object of the present invention, amongst others, to at least partly solve the above identified challenges and problems. In particular, it is an object of the invention to provide a retention system for a substantially aerodynamic helmet that allows relatively easy and practical operation.

[07] According to a first aspect of the invention, this object is achieved by a retention system for a helmet as claimed in claim 1 . The retention system comprises a head basket that is attachable to an inner surface of the helmet. The head basket is configured to enclose at least part of a wearer’s head. The retention system further comprises an adjustment system, configured to adjust the head basket along the wearer’s head. The adjustment system further comprises an operating element, configured to allow operation of the adjustment system. In an inventive way, the operating element includes an endless band. In other words, the endless band is an operating element configured to allow operation of the adjustment system. Operation of the endless band can adjust the head basket along a wearer’s head.

[08] It is an advantage that the endless band can be operated through a substantially linear motion, allowing relatively easy and practical operation of the adjustment system. It is a further advantage that the endless band can be operated by at least one finger, or even by one finger only, which is not the case when the operating element is for example a rotatable knob, which can only be operated by at least two fingers. The endless band is a continuous strip or loop of material placed over at least two rotating members, such that the endless band engages part of the circumference of said rotating members. The endless band may further be stretched substantially tight or taut over the at least two rotating members such that the endless band can engage the at least two rotating members and transfer movement of the endless band to a rotation of the at least two rotating members. Such a rotating member may for example be, amongst others, a pulley, a roller, a jockey wheel, a guiding wheel, a sprocket, or any other rotating member known to the person skilled in the art.

[09] In the context of the present application, operation of the adjustment system, in particular operation of the endless band, refers to a movement of the endless band along a longitudinal direction of said endless band. Movement of the endless band along a first longitudinal direction can tighten the head basket along a wearer's head and movement along a second longitudinal direction, substantially inverse or opposite to the first direction, can untighten the head basket. Such a movement of the endless band may be performed through a substantially linear motion, e.g. by at least one finger of a user or even by a single finger. The endless band may preferably include a surface having a sufficient width to be operable by a user. As the band is endless, such a movement along a longitudinal direction of the endless band can cause the endless band to describe a closed loop in a plane including the rotating members. The width of the surface of the endless band can be measured along a direction transverse to said plane of rotation of the closed loop.

[10] The endless band may preferably be made of an elastomeric material, which can be relatively easy to produce and can reduce production costs. The elastomeric material may for example be, amongst others, synthetic rubber, natural rubber, polyurethane, neoprene, a combination thereof, or any other elastomeric material known to the skilled person. Alternatively, the endless band may be made of a thermoplastic material, or any other suitable flexible material known to the person skilled in the art.

[11] The head basket may further comprise at least one lateral leg, wherein the adjustment system may be configured to adjust the at least one lateral leg along the wearer's head. Operation of the adjustment system can thus tighten the at least one lateral leg along a wearer's head. Preferably, the head basket may comprise two lateral legs, each partially enclosing an opposing lateral side of the wearer’s head. The lateral legs may be configured to extend from the back of the wearer's head, at least partially along a lateral side of a wearer's head and may, but need not, join over a front portion of a wearer's head. The at least one lateral leg may preferably comprise at least one attachment element, configured to attach the at least one lateral leg to a helmet, in particular to an inner surface of a helmet. In this way, the at least one lateral leg may be attached to a helmet, for example to a lateral and/or frontal inner side of a helmet.

[12] The endless band may further be oriented such that operation of the adjustment system is configured to be performed through a movement of the endless band along a direction substantially transverse to a plane including the at least one lateral leg. Such a plane may be defined by a single lateral leg, as the at least one lateral leg may be substantially curved to extend at least partially along a lateral side of a wearer's head. Such a plane may for example correspond to a plane including a circumference of a wearer's head, or a plane in which a head circumference can be measured. The circumference of a wearer's head may for example be measured above the eyebrows, above the ears, and around the back of the head. Preferably, said direction substantially transverse to a plane including the at least one lateral leg may be a direction along the sagittal plane of the wearer's head. In other words, when the helmet is worn on a user’s head, the endless band may be oriented in a substantially vertical direction. It is an advantage that this allows easy and practical operation of the adjustment system. Alternatively, said direction substantially transverse to a plane including the at least one lateral leg may be a direction along the coronal plane of the wearer's head or any other plane at an angle to the sagittal plane.

[13] The endless band may further be positioned substantially outside of a plane including the at least one lateral leg. The endless band, i.e. the operating element, may for example be positioned near an upper side of the wearer's head when in use, e.g. near the crown of the wearer's head. In doing so, the head basket, in particular a rear part of the head basket, can be free of an operating element and/or adjustment system. This has the advantage that the head basket can be more comfortable when the wearer’s hair is tied back, for example in a ponytail. It is a further advantage that the drag or air resistance of the adjustment system can be reduced, i.e. the aerodynamics of a helmet comprising said adjustment system can be improved.

[14] The head basket, in particular a rear part of the head basket, may further comprise at least one leg guide configured to guide the at least one lateral leg towards the adjustment system. The at least one leg guide may be a slit or a through- hole, included in a rear part of the head basket or included in a protrusion of the rear part of the head basket, through which the at least one lateral leg can be passed. The at least one lateral leg may thus extend at least partially along a lateral side of a wearer's head, through the at least one leg guide, toward the adjustment system. As such, operation of the adjustment system can adjust the rear part of the head basket along the back of a wearer's head in a direction along a plane including a circumference of a wearer's head, in addition to a direction substantially transverse to said plane. It is a further advantage that the head basket can be tightened with a substantial equal force along the circumference of the wearer's head, providing a more comfortable and secure fit of the head basket by reducing pressure points.

[15] The adjustment system may further comprise a rack and pinion system, operatively connected to the endless band. The rack and pinion system may comprise at least one pinion gear that engages at least one rack. The pinion gear may be included in at least one of the rotating members over which the endless band is placed or may be operatively connected to at least one of said rotating members. Movement of the endless band can thus easily be transferred to a rotation of the at least one pinion gear that engages the at least one rack. Alternatively, the adjustment system may include any other element or system known to the person skilled in the art which is configured to transfer rotation of the operating element, in particular of the endless band, to the adjustment system resulting in an adjustment of the head basket along a wearer’s head.

[16] The at least one lateral leg, in particular an end of the at least one lateral leg, may further include the at least one rack of the rack and pinion system. The at least one rack may preferably be included in a first end of the at least one lateral leg, extending in the direction of the adjustment system. Alternatively, the at least one rack may be included anywhere along the at least one lateral leg. The at least one rack can be driven by a rotation of the at least one pinion gear, which can be rotated by movement of the endless band around the at least two rotating members. As such, the at least one lateral leg can be adjusted along a wearer's head through operation of the endless band.

[17] The head basket may further comprise at least one upper leg, attachable to an upper inner surface of the helmet, configured to at least partially enclose an upper portion of the wearer's head. In other words, the at least one upper leg may extend from the head basket, in particular a rear part of the head basket, and be configured to extend along the back side and the upper side of the wearer’s head, i.e. the crown of the wearer’s head. The at least one upper leg may preferably comprise at least one attachment element, configured to attach the at least one upper leg to a helmet. In other words, the at least one upper leg, for example an end of said at least one upper leg, may be attached to a helmet. Attachment to a helmet may for example be done to an upper and/or frontal inner side of the helmet.

[18] The at least one upper leg may further be adjustably connected to the head basket, wherein the adjustment system may be configured to adjust the at least one upper leg along the wearer’s head. The head basket, in particular a rear part of the head basket, may thus be adjusted along a direction substantially transverse to a plane including the circumference of a wearer's head. Said substantially transverse direction may preferably be a direction along the sagittal plane of a wearer's head. Alternatively, said substantially transverse direction may be a direction along any other plane at an angle to the sagittal plane. A length of the at least one upper leg may preferably be adjustable by the adjustable connection to the head basket. It is a further advantage that the head basket can be adjusted along the sagittal plane of the wearer's head, providing a more comfortable and secure fit of the head basket by reducing pressure points. In combination with the at least one leg guide, a circumferential fit of the head basket may even be adjusted substantially simultaneously with a height adjustment of the head basket on a wearer’s head.

[19] According to a second aspect, the invention relates to a helmet having the features of claim 11. The helmet comprises at least an outer protective shell, covering an inner shock-absorbing layer. The helmet further comprises a retention system according to the first aspect of the invention as described above for securing the helmet to a wearer’s head. Such a helmet can provide one or more of the above- mentioned advantages.

[20] The outer protective shell of the helmet may further include a cut-out through which at least part of the endless band may be exposed to allow operation of the adjustment system. Preferably, at least part of the outer surface of the endless band may be exposed, i.e. the operating portion of the endless band. Said operating portion of the endless band refers to the portion of the outer surface of the endless band facing away from the wearer's head when in use. The cut-out may be positioned at a lower outer limit of the protective shell, such that the cut-out forms an indent in the outer protective shell periphery. The wording ‘lower’ refers to a position of the periphery or perimeter of the outer protective shell when the helmet is worn by a wearer. However, the cut-out may preferably be positioned such that the cut-out is enclosed on all sides by the outer protective shell, e.g. at an upper portion of the helmet near the top or the crown of a wearer's head when the helmet is in use. It is a further advantage that the endless band can be integrated into a helmet body.

[21] Preferably, at least part of the endless band may be substantially flush with the outer protective shell of the helmet. In particular, at least part of the outer surface of the endless band, in particular at least part of the operating portion of the endless band, may be substantially flush with the outer protective shell of the helmet. Said outer surface of the endless band refers to the surface of the endless band facing away from the rotating members. In other words, at least part of the outer surface of the endless band may be substantially level or even with the surface of the outer protective shell of the helmet. It is a further advantage that the drag or air resistance of the helmet can be reduced, i.e. the aerodynamics of the helmet can be improved.

[22] The adjustment system may further be at least partially recessed in the helmet, in particular into the shock-absorbing layer of the helmet. The shockabsorbing layer may thus include a recess, cavity or depression configured to receive at least part of the adjustment system. Preferably, a depth of the recess in the shockabsorbing layer may be such that the remaining shock-absorbing layer under the recess, i.e. between the recessed adjustment system and the inner surface of the helmet, can be sufficiently thick, for example at least 10 mm, preferably more than 15 mm, to provide relatively good protection to the wearer’s head. Thereto, the shockabsorbing layer towards the back of the helmet may for example be thicker than towards the front of the helmet. As such, the head of a wearer can remain covered by shock-absorbing layer material even where the adjustment system is recessed in the helmet. It is a further advantage that the helmet can provide relatively good protection to the wearer's head even where the adjustment system can be at least partially recessed in the helmet.

[23] According to a third aspect, the invention relates to a method of adjustment of a retention system for a helmet having the features of claim 15. Such a method can provide one or more of the above-mentioned advantages.

Brief Description of the Drawings

[24] Fig 1 shows a cross-sectional side view on a preferred embodiment of a helmet according to a second aspect of the invention including a retention system for securing the helmet to a wearer's head according to a first aspect of the invention;

[25] Fig. 2 shows a side view on a preferred embodiment of an adjustment system included in the retention system of the helmet of Fig. 1 ;

[26] Fig. 3 shows a perspective view on the retention system included in the helmet of Figure 1 .

Detailed Description of Embodiment(s)

[27] Fig 1 shows a cross-sectional side view on a preferred embodiment of a helmet 100 comprising a retention system for securing the helmet to a wearer's head by providing an adjustable fit along for example the circumference of a wearer's head. To protect the head of a wearer from impact related injury, the helmet 100 may include at least an outer protective shell (not shown) covering an inner shockabsorbing layer 101. The outer protective shell may be a substantially thin layer of relatively strong material, e.g. polycarbonate, configured to disperse the energy of an impact across the surface of the outer protective shell. The inner shock-absorbing layer 101 may be substantially thicker compared to the outer protective shell. The inner shock-absorbing layer 101 may be configured to compress around the point of impact such that the energy of the impact can be absorbed. The shock-absorbing layer 101 may for example be made of expanded polystyrene, EPS, foam or any other suitable material as is known to the person skilled in the art. The inner shockabsorbing layer may further include a plurality of protrusions 102 which may be configured to rupture when a force at impact exceeds a predefined threshold. The outer protective shell and the inner shock-absorbing layer 101 may further include a plurality of openings to provide fresh air and to expel perspiration, i.e. to provide ventilation to a wearer's head when in use.

[28] The helmet 100 further comprises a retention system for securing the helmet 100 to a wearer’s head by providing an adjustable fit along for example the circumference of a wearer's head. The circumference of a wearer's head refers to the largest circumference measured above the eyebrows, above the ears, and around the back of the head. The retention system comprises a head basket 300, configured to enclose at least part of a wearer's head. Preferably, the head basket 300 is configured to enclose at least the back of a wearer's head. The retention system further comprises an adjustment system 200, configured to adjust the head basket 300 along a wearer's head. The adjustment system 200 includes an operating element, in particular an endless band 201 , configured to allow operation of the adjustment system 200. Operation of the adjustment system 200 allows tightening and loosening of the head basket 300 at least along the circumference of a wearer's head, and optionally adjusting a height of the head basket on a wearer’s head.

[29] The head basket 300 may at least include a rear part 301 , configured to enclose at least the back of a wearer's head. The rear part 301 of the head basket may further include at least one, and preferably a plurality of, aeration openings 302 to provide fresh air and to expel perspiration, i.e. provide ventilation to the wearer's head when in use. By including such aeration openings 302, a relatively comfortable head basket 300 can be provided, in particular during strenuous activity when perspiration may accumulate between the wearer's head and the head basket 300. The head basket 300 may further be made of a relatively limited amount of material, reducing cost and weight. The aeration openings 302 may further vary in shape, size, and arrangement according to the desired level of ventilation, weight savings, or production costs.

[30] The lower outer limit of the rear part 301 of the head basket, i.e. the lower periphery, may preferably comprise an indent 310 in a substantially middle portion of said rear part 301 , i.e. a portion that is configured to cover substantially the middle of the back of the wearer’s head. The wording ‘lower’ refers to a position of the periphery or perimeter of the head basket 300 when worn by a wearer, which is lowest at the back of a wearer’s head. The indent may extend substantially towards a middle of the head basket 300 and/or may extend upwardly when the head basket 300 is worn by a user, to provide sufficient space for tied back hair to freely be passed. A middle of the rear part 301 of the head basket may be configured to cover the crown of the wearer’s head. Preferably, the indent is located in a central portion of the rear part 301 of the head basket relative to opposite lateral sides of said central portion of the lower periphery. This may result in a head basket 300 that is more comfortable when the wearer’s hair is tied back, for example in a ponytail.

[31] The head basket 300 may comprise at least one lateral leg 303. The at least one lateral leg may be configured to extend at least partially along a lateral side of a wearer's head and may, but need not, join over a front portion of a wearer's head. The at least one lateral leg 303 may thus for example extend from the back of the wearer's head, along a lateral side of the wearer’s head, towards a front portion of the wearer's head. Preferably, the head basket 300 may comprise two lateral legs

303, each partially enclosing an opposing lateral side of the wearer’s head. The lateral legs may be configured to extend from the back of the wearer's head, at least partially along a lateral side of a wearer's head and may, but need not, join over a front portion of a wearer's head. Alternatively, two lateral legs 303 may join and form a single band configured to extend over a front side of a user’s head.

[32] The lateral legs 303 may preferably comprise at least one attachment element

304, 305, configured to attach the lateral legs 303 to the helmet 100, in particular an inner surface of the helmet 100. The lateral legs 303 may be attached to the helmet 100 for example towards an end of the lateral legs 303 or at any other place along the lateral leg 303. The lateral legs 303 may for example be attached to a lateral and/or frontal inner side of the helmet 100. The attachment elements 304, 305 may for example be, amongst others, retainers, screws, bolts, rivets, grommets, plugs, pins, snap fasteners, or snap fits or any other attachment elements known to the person skilled in the art. The helmet 100, in particular an inner side of the helmet, may comprise corresponding elements configured to receive the attachment elements 304, 305. The attachment elements 304, 305 may further provide a releasable or permanent connection to the helmet 100.

[33] The head basket 300 may further comprise at least one upper leg 306, which may extend from the head basket 300, in particular the rear part 301 of the head basket, and may be configured to extend along the back side and the upper side of the wearer's head, i.e. the crown of the wearer's head. In other words, the at least one upper leg 306 may be configured to at least partially enclose an upper portion of the wearer's head when in use. Preferably, the at least one upper leg 306 may comprise at least one attachment element 307, 308, configured to attach the at least one upper leg 306 to the helmet 100. The at least one upper leg 306 may preferably be attached to an upper inner surface of the helmet 100. Alternatively, or complementary, attachment to the helmet 100 may be done to a frontal inner side of the helmet 100. The at least one upper leg 306 may be attached to the helmet 100 for example towards an end of the at least one upper leg 306 or at any other place along the at least one upper leg 306.

[34] Preferably, the at least one upper leg 306 may be adjustably connected 309 to the head basket 300, in particular the rear part 301 of the head basket. Preferably, the length of the at least one upper leg may be adjustable by the adjustable connection 309 to the head basket 300. In other words, the rear part 301 of the head basket can be adjusted to enclose a substantially lower or higher part of the back of a wearer's head when in use. The adjustable connection 309 may for example include, amongst others, a linear ratchet mechanism, a leadscrew, a translation screw, a ball screw, or any other adjustable connection known to the person skilled in the art. Alternatively, the length of the at least one upper leg may be fixed. The adjustment system 200 may further be configured to adjust the at least one upper leg 306 along the wearer's head. The head basket, in particular a rear part of the head basket, may thus be adjusted along a direction substantially transverse to a plane including the circumference of a wearer's head. Said substantially transverse direction may preferably be a direction along the sagittal plane of a wearer's head. Alternatively, said substantially transverse direction may be a direction along any other plane at an angle to the sagittal plane.

[35] The outer protective shell of the helmet 100 may further include a cut-out, i.e. a portion free of material. The outer limits or periphery of the cut-out may, but need not, have a substantially longitudinal shape, the cut-out may also have any other shape, as long as at least part of the adjustment system 200 can be enclosed by the outer limits of the cut-out. The cut-out may preferably be positioned such that the cutout is enclosed by the outer protective shell on all sides, e.g. at an upper portion of the helmet near the top or the crown of a wearer's head when in use. Alternatively, the cut-out may be positioned at a lower outer limit of the protective shell, such that the cut-out forms an indent in the periphery of the outer protective shell. The wording ‘lower’ refers to a position of the periphery or perimeter of the outer protective shell when the helmet is worn by a wearer.

[36] Preferably, the adjustment system 200 may be at least partially recessed in the helmet 100, in particular into the shock-absorbing layer 101. The recess portion in the inner shock-absorbing layer 101 of the helmet 100 may be configured to receive at least part of the adjustment system 200. In other words, the helmet 100 may include an outer protective shell with a cut-out and an inner shock-absorbing layer 101 with a recess, cavity or depression. The cavity may include a shape substantially matching the shape of the cut-out, such that the adjustment system 200 can be partially recessed in the helmet body, i.e. in the cut-out and cavity. Alternatively, the recess in the shock-absorbing layer may be wider than the cut-out in the outer protective shell. Preferably, a depth of the recess in the shock-absorbing layer, which may for example be around 20 mm or more or less, is such that the remaining shock-absorbing layer under the recess, i.e. between the recessed adjustment system 200 and the inner surface of the helmet 100, is still sufficiently thick, for example 10 mm, preferably more than 15 mm, to provide relatively good protection to the wearer’s head. Thereto, the shock-absorbing layer 101 towards the back of the helmet may for example be thicker than towards the front of the helmet. As such, the head of a wearer can remain covered by shock-absorbing layer 101 material even where the adjustment system 200 is recessed in the helmet 100.

[37] At least part of the endless band 201 may be exposed through the cut-out in the outer protective shell to allow operation of the adjustment system 200. Preferably, at least part of the outer surface of the endless band 201 may be exposed, in particular at least part of a longitudinal portion of the outer surface of the endless band 201 between the rotating members, i.e. the operating portion of the endless band 201 . Preferably, at least part of the outer surface of the endless band 201 may be substantially level or even with the surface of the outer protective shell of the helmet 100. In particular, the operating surface of the endless band 201 , or at least part of the operating surface, may be substantially flush with the outer protective shell of the helmet 100. As such, the helmet 100 can be relatively aerodynamic thanks to the at least partially recessed adjustment system 200 inside the helmet body and part of the endless band being substantially flush with the outer protective shell, such that airflow can only be minimally obstructed around the helmet 100.

[38] Fig. 2 shows a side view on a preferred embodiment of an adjustment system 200 included in the retention system of the helmet of Fig. 1 . The adjustment system

200 is configured to adjust the head basket along a wearer's head, effected through operation of an operating element, including an endless band 201. The endless band

201 is a belt having two ends fastened together or a continuous strip or loop without ends. The endless band is preferably stretched between two pulleys or rotating members 202, 203. In other words, the endless band 201 may be a thin strip of material, preferably an elastomeric material, having its ends joined to form a continuous loop of material. The elastomeric material may for example be, amongst others, synthetic rubber, natural rubber, polyurethane, neoprene, any combination thereof, or any other elastomeric material known to the skilled person. The outer surface is preferably sufficiently wide to be operated, e.g. by at least one finger of a user. The width of the outer surface of the endless band 201 may be measured along a direction substantially transverse to a longitudinal direction of the endless band 201. The endless band 201 may for example have a width of at least 10 mm, more preferably of around 20 mm, or more. The outer surface of the endless band, i.e. the surface facing away from the rotating members 202, 203, may further include a plurality of protuberances configured to facilitate operation of the endless band 201 by providing a substantially rough or uneven outer surface. Such protuberances may for example be teeth, knobs, or lumps arranged to form a pattern. This can provide a relatively good grip for a user's fingers to operate the endless band 201 , i.e. the adjustment system 200, with relative ease, for example by one or more fingers.

[39] Operation of the adjustment system 200, in particular operation of the endless band 201 , refers to a movement of the endless band 201 along a longitudinal direction 210 of said endless band 201 . Such operation of the endless band 201 may for example be performed by one or more finger of a user or by the hand of a user. Movement of the endless band 201 along a first longitudinal direction 210 can tighten the head basket along a wearer's head and movement along a second longitudinal direction, substantially inverse or opposite to the first direction 210, can untighten the head basket. As the band 201 is endless, such a movement along a longitudinal direction of the endless band 201 causes the endless band to describe a closed loop in a plane including the rotating members or transverse to an axis of rotation of the rotating members.

[40] The adjustment system 200 may further comprise a rack and pinion system, operatively connected to the endless band 201. The rack and pinion system may include at least one pinion gear 222 and at least one rack 221 , preferably two pinion gears 222 and two racks 221 , i.e. linear gears, which two racks and/or two pinion gears may for example be located on opposite lateral sides of the adjustment system 200. The pinion gear 222 may be configured to engage the rack 221 , or vice-versa. By the operative connection, a movement of the endless band 201 can be transferred to a rotation of the at least one pinion gear 222 and a linear movement of the at least one rack 221.

[41] Such an operative connection between the endless band 201 and the rack and pinion system can generally include two rotating members 202, 203, which are configured to support movement of the endless band 201 around an axis of rotation of said rotating member. Such a rotating member may for example be, amongst others, a pulley, a roller, a jockey wheel, a guiding wheel, a sprocket, or any other rotating member known to the person skilled in the art. The at least one pinion gear 222 of the rack and pinion system may preferably be operatively connected to a first rotating member 203, at least partially enclosed by the endless band 201. The first rotating member 203 may be positioned such that the endless band 201 embraces part of the circumference of the first rotating member 203. The circumference of the first rotating member 203 refers to the outer surface of the rotating member, which may for example be substantially concentric around the axis of rotation of said member 203. The adjustment system 200 may further comprise a second rotating member 202. The second rotating member 202 may be positioned at a distance of and/or opposite to the first rotating member 203, such that the endless band 201 embraces part of the circumference of the second rotating member 203. A distance between the first rotating member 203 and the second rotating member 202 may for example be in a range of more or less 30 mm to 45 mm, for preferably between more or less 35 mm and 40 mm, for example around 37 mm. The endless band 201 may further be stretched relatively tight by the first 203 and second rotating member 202. The wording 'stretched substantially tight' refers to substantially removing the slack from the endless band 201 such that the opposing surfaces of the endless band 201 , extending between the first 203 and second 202 rotating member, do not warp or bend substantially. As a result, the traction of the endless band 201 on the two rotating members 202, 203 can take hold of the members 202, 203 and transfer movement of the endless band 201 to a rotation of the rotating members 202, 203. In other words, operation of the endless band 201 , i.e. movement of the endless band 201 , can be transferred to a rotation of the two rotating members 202, 203. The diameter of the rotating members 202, 203 for example between more or less 5 mm to more or less 20 mm, in particular the ratio of their diameters, for example a ratio of more or less 2:1 , may be determined to achieve a mechanical advantage when operating the endless band 201 , in particular to allow relatively easy operation of the adjustment system 200.

[42] The inner surface of the endless band 201 , i.e. the surface facing towards the centreline of the endless band 201 , may further be substantially jagged and include a plurality of teeth or protuberances configured to maintain substantial contact between the endless band and the rotating members 202, 203. These protuberances can improve the traction of the endless band 201 on the rotating members 202, 203 by for example including teeth, knobs, or lumps onto the inner surface of the endless band 201 , configured to engage the outer surface of the rotating members 202, 203. The members 202, 203 may further include corresponding recesses that match the shape of the protuberances, configured to receive the protuberances as the endless band 201 moves around said members 202, 203.

[43] The adjustment system 200 may further comprise one or more rollers 223, at least partially enclosed by the endless band 201 , which may be positioned between the first and second rotating members 202, 203. The one or more rollers 223 may preferably be positioned such that at least part of their circumference may be engaged by the endless band 201 . Preferably, the rollers may be partially engaged by the inner surface of the endless band 201 . By supporting the operating surface of the endless band 201 , inward flexing of the endless band 201 may substantially be reduced during operation, which flexing may be caused by the exerted force on the band 201 during operation. Additionally, the one or more rollers 223 may allow motion of the endless band with substantially reduced friction, i.e. allow relatively easy operation of the adjustment system 200.

[44] The adjustment system 200 may further be configured to adjust the at least one lateral leg 303 along the wearer's head. This lateral leg 303, in particular an end of the lateral leg 303, may therefore include the at least one rack 221 of the rack and pinion system. The rack 221 may extend towards the adjustment system 200 to be engaged by the pinion gear 222, operatively connected to the first rotating member 203. As such, operation of the adjustment system 200, in particular of the endless band 201 , can tighten the at least one lateral leg along a wearer's head. Preferably, the adjustment system 200 may adjust two lateral legs 303, each partially enclosing an opposing lateral side of the wearer’s head, and each comprising a rack 221 at their respective ends. The adjustment system 200 may preferably comprise two pinion gears 222, each operatively connected to the first rotating member 203, and each engaging one of the two racks 221 included in the respective lateral legs 303. The two pinion gears 222 may for example be operatively connected to the rotating member 203 and may each be located at opposing sides of the rotating member 203.

[45] Fig. 3 shows a perspective view on a preferred embodiment of a retention system 400 for securing a helmet to a wearer's head. The head basket 300 of the retention system 400, in particular a rear part 301 of the head basket, may comprise at least one, or preferably a plurality of, leg guides 311 , 312 configured to guide the lateral legs 303 towards the adjustment system 200. The at least one leg guide 311 , 312 may for example be, amongst others, a slit, or a through-hole included in the rear part 301 of the head basket, through which the lateral legs 303 can be passed. The preferably two lateral legs 303 may thus preferably extend along opposing lateral sides of the wearer’s head, through the leg guides 311 and 312, towards the adjustment system 200. As such, the rack 221 at an end of the lateral legs 303 can be engaged by the pinion gears of the adjustment system 200. Thanks to the leg guides 311 , 312 operation of the adjustment system 200 can, in addition to adjusting the lateral legs 303, adjust the rear part 301 of the head basket along the wearer's head, in particular along the back of the wearer's head. In doing so, the adjustment system 200 may tighten the head basket 300 along opposing lateral sides and the back side of the wearer's head with a substantially equal force.

[46] The operating element of the adjustment system 200, in particular the endless band 201 , may preferably be positioned substantially outside of a plane including at least partially the lateral legs 303. Such a plane may for example correspond to a plane including a circumference of a wearer's head, or a plane in which a head circumference can be measured. The endless band 201 may for example be positioned near an upper side of the wearer's head when in use, in particular near the crown of the wearer's head. The rear part 301 may be pulled towards the adjustment system 200 by tightening the lateral legs 303 through operation of the adjustment system 200. Additionally, when the head basket includes an adjustable connection 309 between the upper leg 360 and the rear part 301 of the head basket, a position of the rear part of the head basket can be adjusted with respect to a crown of a wearer’s head, depending on specific shape and dimensions of a wearer’s head. As such, the rear part 301 of the head basket can be adjusted to enclose a substantially lower or higher part of the back of a wearer's head when in use. In other words, operating the adjustment system 200 can adjust the rear part 301 of the head basket along the wearer's head in a direction along a plane including the circumference of a wearer's head in addition to a direction substantially transverse to said plane. [47] Preferably, the endless band 201 may be oriented such that operation of the adjustment system 200 is configured to be performed through a movement of the endless band 201 along a direction substantially transverse to said plane, i.e. a plane including the circumference of a wearer's head. In other words, when the helmet is worn on a user’s head, the endless band may be oriented in a substantially vertical direction. Alternatively, the endless band may be oriented such that operation of the adjustment system 200 is configured to be performed through a movement of the endless band 201 along a plane including the circumference of a wearer's head.

[48] Although the present invention has been illustrated by reference to specific embodiments, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied with various changes and modifications without departing from the scope thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. In other words, it is contemplated to cover any and all modifications, variations or equivalents that fall within the scope of the basic underlying principles and whose essential attributes are claimed in this patent application. It will furthermore be understood by the reader of this patent application that the words "comprising" or "comprise" do not exclude other elements or steps, that the words "a" or "an" do not exclude a plurality, and that a single element, such as a computer system, a processor, or another integrated unit may fulfil the functions of several means recited in the claims. Any reference signs in the claims shall not be construed as limiting the respective claims concerned. The terms "first", "second", third", "a", "b", "c", and the like, when used in the description or in the claims are introduced to distinguish between similar elements or steps and are not necessarily describing a sequential or chronological order. Similarly, the terms "top", "bottom", "over", "under", and the like are introduced for descriptive purposes and not necessarily to denote relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances and embodiments of the invention are capable of operating according to the present invention in other sequences, or in orientations different from the one(s) described or illustrated above.

Claims

1 . A retention system (400) for a helmet (100), the retention system comprising:

- a head basket (300), attachable to an inner surface of the helmet, configured to enclose at least part of a wearer’s head;

- an adjustment system (200), configured to adjust the head basket along the wearer’s head; and wherein the adjustment system further comprises an operating element, configured to allow operation of the adjustment system, wherein the operating element includes an endless band (201 ).

2. The retention system according to claim 1 , wherein the endless band (201 ) is made of an elastomeric material.

3. The retention system according to any of the preceding claims, wherein the head basket (300) comprises at least one lateral leg (303), wherein the adjustment system (200) is configured to adjust the at least one lateral leg along the wearer’s head.

4. The retention system according to claim 3, wherein the endless band (201 ) is oriented such that operation of the adjustment system (200) is configured to be performed through a movement of the endless band along a direction substantially transverse to a plane including the at least one lateral leg (303).

5. The retention system according to any of the preceding claims 3-4, wherein the endless band (201 ) is positioned substantially outside of a plane including the at least one lateral leg (303).

6. The retention system according to any of the preceding claims 3-5, wherein the head basket (300), in particular a rear part (301 ) of the head basket, further comprises at least one leg guide (311 , 312) configured to guide the at least one lateral leg (303) towards the adjustment system (200).

7. The retention system according to any of the preceding claims, wherein the adjustment system (200) further comprises a rack and pinion system, operatively connected to the endless band (201 ).

8. The retention system according to at least claims 3 and 7, wherein an end of the at least one lateral leg (303) includes at least one rack (221 ) of the rack and pinion system.

9. The retention system according to any of the preceding claims, wherein the head basket (300) further comprises at least one upper leg (306), attachable to an upper inner surface of the helmet (100), configured to at least partially enclose an upper portion of the wearer's head.

10. The retention system according to claim 9, wherein the at least one upper leg (306) is adjustably connected to the head basket (300), wherein the adjustment system is configured to adjust the at least one upper leg along the wearer’s head.

11. A helmet (100) comprising at least an outer protective shell covering an inner shock-absorbing layer (101 ), the helmet further comprising a retention system (400) according to any of the preceding claims for securing the helmet to a wearer’s head.

12. The helmet according to claim 11 , wherein the outer protective shell includes a cut-out through which at least part of the endless band (201 ) is exposed to allow operation of the adjustment system (200).

13. The helmet according to any of the preceding claims 11 - 12, wherein at least part of the endless band (201 ) is substantially flush with the outer protective shell of the helmet.

14. The helmet according to any of the preceding claims 11 - 13, wherein the adjustment system (200) is at least partially recessed in the helmet (100), in particular into the shock-absorbing layer (101 ) of the helmet.

15. Method of adjustment of a retention system for a helmet, the method comprising the steps of:

- providing a retention system (400) including a head basket (300), attachable to an inner surface of the helmet (100), configured to enclose at least part of a wearer’s head, and an adjustment system (200), configured to adjust the head basket along the wearer’s head; and

- adjusting the head basket along the wearer’s head by operating an endless band (201 ).