# Patent

## Title
Sport helmet

## Abstract

A sport helmet for protecting a head of a wearer, such as a hockey, lacrosse or football player. The sport helmet has an outer shell with an internal side and an external side and an inner pad mounted to the internal side of the outer shell for absorbing shocks when the sport helmet is impacted. The inner pad has a core of polymeric cellular material with a body of expanded polymeric microspheres and a molded covering being molded onto the core of polymeric cellular material.

## Background
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit under 35 USC 119(e) of U.S. Provisional Patent Application 61/512,325 filed on Jul. 27, 2011 and hereby incorporated by reference herein.


FIELD OF THE INVENTION
The invention relates to sport helmets for protecting heads of wearers engaged in various sports, such as hockey, lacrosse, and football players.
BACKGROUND
Sport helmets are used in many sports, such as hockey, lacrosse and football, to name a few, for protecting their wearer's head.
For example, a hockey helmet for protecting a hockey player's head typically comprises an outer shell providing strength and rigidity for impact resistance and an inner pad contacting the hockey player's head and absorbing shocks when the hockey helmet is impacted (e.g., when the hockey helmet hits a board or an ice or other skating surface of a hockey rink or is struck by a puck or a hockey stick). To that end, the outer shell is made of rigid material such as hard plastic while the inner pad is made of shock-absorbing material such as polymeric foam mounted (e.g., by an adhesive or fasteners) to the outer shell's internal side. Helmets for other sports, such as lacrosse or football for example, sometimes have similar constructions.
Impact resistance and shock absorbance of a sport helmet are crucial for proper protection of a wearer's head, while weight of the sport helmet is often important for comfort and/or performance of the wearer.
Although there have been advances in sport helmet designs, there remains a need for improvements in sport helmets, including improvements directed to enhancing shock absorbance while reducing weight of sport helmets.
SUMMARY OF THE INVENTION
According to an aspect of the invention, there is provided a sport helmet for protecting a head of a wearer. The sport helmet comprises an outer shell comprising an internal side and an external side. The sport helmet also comprises an inner pad mounted to the internal side of the outer shell for absorbing shocks when the sport helmet is impacted. The inner pad comprises a core of polymeric cellular material and a covering on the core of polymeric cellular material.
According to another aspect of the invention, there is provided a sport helmet for protecting a head of a wearer. The sport helmet comprises an outer shell comprising an internal side and an external side. The sport helmet also comprises an inner pad mounted to the internal side of the outer shell for absorbing shocks when the sport helmet is impacted. The inner pad comprises a core of polymeric cellular material comprising expanded polymeric microspheres. Each of the expanded polymeric microspheres comprises a polymeric shell having been expanded by a fluid encapsulated in the polymeric shell. The inner pad also comprises a covering enveloping the core of polymeric cellular material.
According to another aspect of the invention, there is provided a sport helmet for protecting a head of a wearer. The sport helmet comprises an outer shell comprising an internal side and an external side. The outer shell comprises a first outer shell member and a second outer shell member that are movable relative to one another to adjust a size of the sport helmet. The sport helmet also comprises an inner pad mounted to the internal side of the outer shell for absorbing shocks when the sport helmet is impacted. The inner pad comprises a first pad member mounted to the first outer shell member. The first pad member comprises a first core of polymeric cellular material and a first covering on the first core of polymeric cellular material.
The inner pad also comprises a second pad member mounted to the second outer shell member. The second pad member comprises a second core of polymeric cellular material and a second covering on the second core of polymeric cellular material.
These and other aspects of the invention will now become apparent to those of ordinary skill in the art upon review of the following description of embodiments of the invention in conjunction with the accompanying drawings.



BRIEF DESCRIPTION OF THE DRAWINGS
A detailed description of embodiments of the invention is provided herein below, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 shows a front perspective view of an example of a sport helmet in accordance with an embodiment of the invention;
FIG. 2 shows a rear perspective view of the sport helmet;
FIG. 3 shows another rear perspective view of the sport helmet in which an actuator of an adjustment mechanism is in a release position;
FIGS. 4 to 7 show side views of the sport helmet in which a size of the sport helmet is adjusted;
FIG. 8 shows a front perspective exploded view of the sport helmet;
FIG. 9 shows a rear perspective exploded view of the sport helmet;
FIG. 10 shows a side view of a pad member of an inner pad of the sport helmet;
FIG. 11 shows a cross-sectional view of the sport helmet;
FIG. 12 shows a rear perspective exploded view of the sport helmet in which a covering of the inner pad is decorated;
FIG. 13 is a perspective view of a head of a wearer of the sport helmet; and
FIG. 14 is a right side elevational view of the head of the wearer.



In the drawings, embodiments of the invention are illustrated by way of examples. It is to be expressly understood that the description and drawings are only for the purpose of illustration and are an aid for understanding. They are not intended to be a definition of the limits of the invention.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
FIGS. 1 and 2 show an example of a sport helmet 10 for protecting a head of a wearer in accordance with an embodiment of the invention. In this embodiment, the sport helmet 10 is a hockey helmet for protecting a hockey player's head.
The hockey helmet 10 covers various regions of the hockey player's head. As shown in FIGS. 13 and 14, the head of the hockey player comprises a crown region CR, a top region TR, left and right side regions LS, RS, a back region BR, and an occipital region OC. The crown region CR has a front part that substantially corresponds to the forehead and a top part that substantially corresponds to the front top part of the head. The crown region CR generally corresponds to the frontal bone region of the head. The left and right side regions LS, RS are approximately located above the player's ears. The occipital region OC substantially corresponds to the region around and under the head's external occipital protuberance.
With additional reference to FIGS. 8 and 9, in this embodiment, the hockey helmet 10 comprises an outer shell 11 and an inner pad 15. The outer shell 11 comprises an internal side 17 and an external side 19. The inner pad 15 is positioned on the internal side 17 of the outer shell 11 such that, in use, the inner pad 15 is disposed between the outer shell 11 and the hockey player's head and absorb shocks when the hockey helmet 10 is impacted (e.g., when the hockey helmet 10 hits a board or an ice or other skating surface of a hockey rink or is struck by a puck or a hockey stick).
The outer shell 11 provides strength and rigidity to the hockey helmet 10. To that end, the outer shell 11 is made of rigid material. For example, in various embodiments, the outer shell 11 may be made of thermoplastic material such as polyethylene, polyamide (nylon), or polycarbonate, of thermosetting resin, or of any other suitable material. In this example of implementation, the outer shell 11 comprises a plurality of ventilation holes 391-39V allowing air to circulate around the player's head for added comfort.
In this embodiment, the outer shell 11 comprises a front outer shell member 12 and a rear outer shell member 14 that are connected to one another. The front outer shell 12 comprises a top portion 21 for facing at least part of the top region TR of the player's head, a front portion 23 for facing at least part of the crown region CR of the player's head, and left and right side portions 25, 27 extending rearwardly from the front portion 23 for facing at least part of the left and right side regions LS, RS of the player's head. The rear outer shell member 14 comprises a top portion 29 for facing at least part of the top region TR of the player's head, a rear portion 31 for facing at least part of the back region BR and occipital region OR of the player's head, and left and right side portions 33, 35 extending forwardly from the rear portion 31 for facing at least part of the left and right side regions LS, RS of the player's head. In this case, each of the front and rear outer shell members 12, 14 defines respective ones of the ventilation holes 391-39V of the outer shell 11.
With additional reference to FIGS. 3 to 7, in this embodiment, the front outer shell member 12 and the rear outer shell member 14 are movable relative to one another to adjust a size of the hockey helmet 10 to fit the head of the hockey player. To that end, the hockey helmet 10 comprises an adjustment mechanism 40 connected between the front outer shell member 12 and the rear outer shell member 14 to enable adjustment of the size of the hockey helmet 10 by moving the outer shell members 12, 14 relative to one another in a direction generally parallel to a longitudinal axis of the hockey helmet 10. This is shown in FIGS. 4 to 7 in which the rear outer shell member 14 is moved relative to the front outer shell member 12 in the direction indicated by the arrow in FIG. 5 from a first position, which is shown in FIG. 4 and which corresponds to a relatively small size of the helmet 10, to a second position, which is shown in FIG. 5 and which corresponds to an intermediate size of the helmet 10, and to a third position, which is shown in FIG. 6 and which corresponds to a relatively large size of the helmet 10.
In this embodiment, the adjustment mechanism 40 comprises an actuator 41 that can be pivoted by the hockey player between a locked position, in which the actuator 41 engages a locking part 51 of the front outer shell member 12 and thereby locks the outer shell members 12, 14 relative to one another, and a release position, in which the actuator 41 is disengaged from the locking part 51 of the front outer shell member 12 and thereby permits the outer shell members 12, 14 to move relative to one another so as to adjust the size of the helmet 10. The adjustment mechanism 40 may be implemented in various other ways in other embodiments.
The inner pad 15 is mounted to the internal side 17 of the outer shell 11. For example, in various embodiments, the inner pad 15 may be mounted to the internal side 17 of the outer shell 11 by an adhesive, stitches, fasteners (e.g., tacks, staples, rivets, etc.), or any other suitable attachment means. The inner pad 15 has a three-dimensional external configuration that generally conforms to a three-dimensional internal configuration of the outer shell 11. As further discussed below, the inner pad 15 comprises shock-absorbing material to absorb shocks when the hockey helmet 10 is impacted.
In this embodiment, the inner pad 15 comprises a front left inner pad member 50 for contacting at least part of the crown region CR and left side region LS of the player's head, a front right inner pad member 52 for contacting at least part of the crown region CR and right side region LS of the player's head, a rear left inner pad member 54 for contacting at least part of the back region BR and left side region LS of the player's head, a rear right inner pad member 56 for contacting at least part of the back region CR and right side region LS of the player's head, and a top inner pad member 58 for contacting at least part of the top region TR and back region BR of the player's head. The front outer shell member 12 overlays the front left and right inner pad members 50, 52 while the rear outer shell member 14 overlays the rear left and right rear inner pad members 54, 56 and the top inner pad member 58.
As shown in FIGS. 10 and 11, the front left inner pad member 50 comprises a core of polymeric cellular material 60 and a covering 62 on the core of polymeric cellular material 60.
The core of polymeric cellular material 60 has a periphery 81 comprising an outer side 82 facing outwardly (i.e., towards the outer shell 11), an inner side 86 facing inwardly (i.e., towards the hockey player's head), and a lateral side 84 between the outer side 82 and the inner side 86. The periphery 81 of the core of polymeric cellular material 60 defines the three-dimensional external configuration of the inner pad 15.
As shown in FIG. 11, in this embodiment, a thickness of the core of polymeric cellular material 60 is such that, in a longitudinal cross-section of the sport helmet 10, the core of polymeric cellular material 60 occupies a majority of a thickness measured from the external side 19 of the outer shell 11 to the inner side 86 of the core of polymeric cellular material 60.
The polymeric cellular material 60 is a polymeric material having a cellular structure which forms a network of cells held together. Various types of polymeric cellular material may be used in various embodiments.
For example, in this embodiment, the core of polymeric cellular material 60 comprises a body of expanded polymeric microspheres 701-70M. Each expanded polymeric microsphere 70x comprises a polymeric shell 72 that has been expanded by a fluid encapsulated in an interior of the polymeric shell 72. In this example of implementation, the polymeric shell 72 of the expanded polymeric microsphere 70x is a thermoplastic shell. The fluid encapsulated in the polymeric shell 72 of the expanded polymeric microsphere 70x is a liquid or gas (in this case a gas) which has been used to expand the microsphere 70x when heated during manufacturing of the front left inner pad member 50, as further discussed below. More particularly, in this example of implementation, the expanded polymeric microspheres 701-70M are EXPANCELTM microspheres commercialized by Akzo Nobel. Various other types of expanded polymeric microspheres 701-70M may be used in other embodiments.
The body of expanded polymeric microspheres 701-70M is at least a main constituent of the core of polymeric cellular material 60. That is, the body of expanded polymeric microspheres 701-70M is a sole constituent of the core of polymeric cellular material 60 or, if the core of polymeric cellular material 60 is constituted of two or more constituents, is the main constituent. For example, in various embodiments, the body of expanded polymeric microspheres 701-70M may represent at least 80%, in some cases at least 85%, in some cases at least 90%, in some cases at least 95%, and in some cases 100% of the core of polymeric cellular material 60 (by weight). In this embodiment, the body of expanded polymeric microspheres 701-70M represents about 95% of the core of polymeric cellular material 60, and a color pigment substance represents about 5% of the core of polymeric cellular material 60.
The expanded polymeric microspheres 701-70M may have various sizes in various embodiments. For example, in some embodiments, the expanded polymeric microsphere 701-70M may have a size between 10 microns and 25 microns before being expanded and a size between 20 microns and 120 microns after being expanded. In other embodiments, the expanded polymeric microspheres 701-70M may have any other suitable sizes. It is noted that in FIGS. 10 and 11 the size of the expanded polymeric microspheres 701-70M is enlarged in order to schematically illustrate them and that the expanded polymeric microspheres 701-70M are considerably smaller in reality.
A density of the body of expanded polymeric microspheres 701-70M may have various values in various embodiments. For example, in some embodiments, the density of the body of expanded polymeric microspheres 701-70M may be less than 0.04 g/cm3, in some cases no more 0.035 g/cm3, and in some cases even less. For instance, in some embodiments, the density of the body of expanded polymeric microspheres 701-70M may be between 0.030 g/cm3 to 0.035 g/cm3. The density of the body of expanded polymeric microspheres 701-70M may have any other suitable value in other embodiments.
In other embodiments, the polymeric cellular material 60 may comprise expanded polypropylene (EPP) foam, expanded polyethylene (EPE) foam, or any other suitable polymeric foam material.
The covering 62 covers at least part of the core of polymeric cellular material 60. This may help to retain integrity of the core of polymeric cellular material 60. In particular, in this embodiment in which the core of polymeric cellular material 60 comprises the body of expanded polymeric microspheres 701-70M, the covering 62 may help to enhance a resistance of the body of expanded polymeric microspheres 701-70M to chipping, crumbling or cracking in use.
In this embodiment, the covering 62 covers at least a majority of the periphery 81 of the core of polymeric cellular material 60. More particularly, in this example, the covering 62 covers at least a majority, in this case all, of the inner side 86 of the core of polymeric cellular material 60. Also, in this example, the covering 62 covers at least a majority, in this case all, of the outer side 82 of the core of polymeric cellular material 60 and at least a majority, in this case all, of the lateral side 84 of the core of polymeric cellular material 60. Thus, in this example, the covering 62 envelopes the core of polymeric cellular material 60. That is, the covering 62 completely encloses the core of polymeric cellular material 60. This may help to maximize an effect of the covering 62 in retaining integrity of the core of polymeric cellular material 60.
The covering 62 may cover less than an entirety of the core of polymeric cellular material 60 in other embodiments. For example, in other embodiments, certain regions of the inner side 86 of the core of polymeric material 60 may not be covered by the covering 62 but may rather be exposed. As another example, in other embodiments, the covering 62 may not cover part or all of the outer side 82 of the core of polymeric cellular material 60.
In this embodiment, the covering 62 comprises a fabric layer 75. More particularly, in this example of implementation, the fabric layer 75 is a non-woven fabric layer. In other examples, the fabric layer 75 may be a woven fabric layer. The fabric layer 75 may be selected such that it has a limited stretching ability to stay firmly on the core of polymeric cellular material 60. For instance, in various embodiments, the fabric layer 75 may comprise spandex, nylon, polyester, polypropylene, or any other suitable fabric material.
More particularly, in this embodiment, the covering 62 comprises a first covering portion 781 covering the outer side 82 and part of the lateral side 84 of the core of polymeric cellular material 60 and a second covering portion 782 covering the inner side 86 and part of the lateral surface 84 of the core of polymeric cellular material 60. The covering portions 781, 782 are joined together at a seam 88 extending along the lateral 84 of the core of polymeric cellular material 60. Specifically, in this embodiment, the fabric layer 75 comprises a first fabric member constituting the first covering portion 781 and a second fabric member constituting the second covering portion 782 and these two fabric members are jointed together at the seam 88.
The covering 62 may be used to enhance an appearance of the front left inner pad member 50. For example, as shown in FIG. 12, in some embodiments, the covering 62 may be decorated such that it displays a decoration 76 that includes an arrangement of two or more different colors. More particularly, in this embodiment, the decoration 76 is a decorative pattern 77 defined by the fabric layer 75. In this case, the decorative pattern 77 includes lines in one color which are spaced apart by areas having another color and which cross other lines. The decorative pattern 77 may take on any other suitable configuration in other cases.
The decoration 76 displayed by the covering 62 may be various other types of decoration in other embodiments. For example, in some embodiments, the arrangement of colors of the decoration 76 displayed by the covering 62 may represent colors and/or a logo of a sports team for which the hockey player plays.
The decoration 76 may be provided in various ways. For example, in this embodiment, the decoration 76 is a sublimated decoration created using a sublimation process on the fabric layer 75. The decoration 76 may be created using any other suitable technique (e.g., painting, drawing, silkscreening, roller printing, pad printing, etc.) in other embodiments.
The covering 62 is affixed to the core of polymeric material 60. More particularly, in this embodiment, the covering 62 is bonded to the core of polymeric cellular material 60 during a molding process used to manufacture the front left inner pad member 50, as further discussed below.
The covering 62 may have any suitable thickness. For example, in some embodiments, the thickness of the covering 62 may be at least 0.05 mm, in some cases at least 0.1 mm, in some cases at least 0.2 mm, in some cases at least 0.3 mm, and in some cases more (e.g., 1 mm). The covering 62 may be thinner than 0.05 mm in some cases.
The covering 62 may have any suitable strength properties. For instance, in some embodiments, the covering 62 may be such that it does not tear or otherwise fail when the hockey helmet 10 is tested to meet a standard (e.g., the Canadian Standards Association (CSA) cold impact resistance standard).
The covering 62 may be implemented in various ways in other embodiments. For example, in other embodiments, the covering 62 may comprise two or more stacked layers (e.g., the fabric layer 75, which may be used for resistance of the covering 62, and an additional fabric layer or non-fabric layer stacked over the fabric layer 75, which may be used for decoration, comfort, antibacterial protection, etc.). As another example, in other embodiments, the covering 62 may comprise a coating of a substance on the core of polymeric cellular material 60 (e.g., by dipping the core of polymeric cellular material 60 in the substance or otherwise applying the substance on the core of polymeric cellular material 60 to form the coating).
In this embodiment, the front inner pad member 50 comprises a plurality of ventilation holes 801, 802. In this case, the ventilation holes 801, 802 are aligned with respective ones of the ventilation holes 391-39V of the outer shell 11. Each ventilation hole 80i of the front inner pad member 50 extends through the core of polymeric cellular material 60 and is defined by an interior surface 89 of the core of polymeric cellular material 60 that is covered by the covering 62. The ventilation holes 801, 802 may have any suitable shape.
The front left inner pad member 50 may be manufactured in various ways. In this embodiment, the front left inner pad member 50 is a molded pad member in which the core of polymeric cellular material 60 is molded into shape and the covering 62 is molded onto the core of polymeric cellular material 60.
More particularly, in this embodiment, the front left inner pad member 50 is manufactured using a manufacturing process which comprises the following steps:

    Step 200: Pre-expansion of unexpanded microspheres. In this step, an amount of unexpanded polymeric microspheres is heated to pre-expand the microspheres, thereby producing pre-expanded microspheres. For example, in this example, an amount of EXPANCELTM dry unexpanded microspheres in a loose powder form is heated to pre-expand the microspheres.
    Step 210: Molding of core of polymeric cellular material. A quantity of the pre-expanded microspheres is placed into a mold for molding the core of polymeric cellular material 60. Any other constituent of the core of polymeric cellular material 60, such as the color pigment substance in this case, may be placed into the mold with the pre-expanded microspheres. Also, in some cases, an amount of expanded microspheres (i.e., microspheres expanded to their final size) may also be added into the mold.
    
        The core of polymeric cellular material 60 is molded in the mold by applying heat. The molding temperature may be higher than the temperature used for the pre-expansion step. As part of the molding process, the pre-expanded microspheres further expand into their final size. The molding process may then include a cold molding phase in which the temperature is lowered. The temperature and pressure of the molding process cause bonding of adjacent ones of the expanded microspheres.
    
    
    Step 220: Molding of covering onto core of polymeric cellular material. The covering 62 is molded onto the core of polymeric cellular material 60. In this embodiment, the covering 62 has been prepared for its placement onto the core of polymeric cellular material 60. More particularly, in this case, the first fabric member and the second fabric member of the fabric layer 75, which will respectively form the first covering portion 781 and the second covering portion 782 of the covering 62, have been previously prepared by cutting them from one or more sheets of fabric. Also, in this case, these two fabric members have been previously decorated with the decoration 76 using a prior sublimation process.
    
        The first fabric member and the second fabric member of the fabric layer 75 are placed into a mold (which may be the same mold as that used in step 210 or a different mold) with the core of polymeric cellular material 60 positioned between them. In this embodiment, a hot-melt adhesive film or another adhesive is associated with each of the first fabric member and the second fabric member of the fabric layer 75 to enhance bonding of the fabric layer 75 to the core of polymeric cellular material 60.
        The first fabric member and the second fabric member of the fabric layer 75 are molded onto the core of polymeric cellular material 60 in the mold by heating. The hot-melt adhesive film or other adhesive associated with each of the first fabric member and the second fabric member of the fabric layer 75 enhances bonding of the fabric layer 75 to the core of polymeric cellular material 60. The seam 88 is created where the first fabric member and the second fabric member of the fabric layer 75 meet. The molding process may then include a cold molding phase in which the temperature is lowered.
    
    
    Step 230: Finishing of pad member. The core of polymeric cellular material 60 with the covering 62 molded onto is removed from the mold and finished. For example, in this embodiment, a trimming operation may be performed to remove excess material from the first fabric member and the second fabric member of the fabric layer 75 that extends beyond the core of polymeric cellular material 60.


The front left inner pad member 50 may be manufactured using various other manufacturing techniques in other embodiments.
In this embodiment, each of the front right inner pad member 52, the rear left inner pad member 54, the rear right inner pad member 56, and the top inner pad member 58 is constructed and manufactured as described above in respect of the front left inner pad member 50. In particular, each of the pad members 52, 54, 56, 58 comprises a core of polymeric cellular material like the core of polymeric cellular material 60 of the pad member 50 and a covering enveloping its core of polymeric cellular material like the covering 62 of the pad member 50.
The inner pad 15 may provide greater shock absorbance while being lighter than conventional foam pads (e.g., vinyl nitrile (VN) or expanded polypropylene (EPP) foam pads) used in hockey helmets.
The inner pad 15 may be configured in various other ways in other embodiments. For instance, in other embodiments, the inner pad 15 may comprise any number of pad members (e.g.: two pad members such as one pad member that contacts at least part of the crown region CR, top region TR, and left and right side regions LS, RS of the player's head and another pad member that contacts at least part of the back region BR, top region TR, and left and right side regions LS, RS of the player's head; a single pad member that contacts at least part of the crown region CR, top region TR, left and right side regions LS, RS, and back region BR of the player's head; etc.).
Although in embodiments considered above the sport helmet 10 is a hockey helmet for protecting the head of a hockey player, in other embodiments, a sport helmet constructed using principles described herein in respect of the sport helmet 10 may be another type of sport helmet for protecting the head of a player of another type of contact sport (sometimes referred to as “full-contact sport” or “collision sport”) in which there are significant impact forces on the player due to player-to-player and/or player-to-object contact. For example, in one embodiment, a sport helmet constructed using principles described herein in respect of the sport helmet 10 may be a lacrosse helmet for protecting the head of a lacrosse player. As another example, in one embodiment, a sport helmet constructed using principles described herein in respect of the sport helmet 10 may be a football helmet for protecting the head of a football player.
To facilitate the description, any reference numeral designating an element in one figure designates the same element if used in any other figures. In describing the embodiments, specific terminology was resorted to for the sake of clarity but the invention is not intended to be limited to the specific terms so selected, and it is understood that each specific term comprises all equivalents.
Unless otherwise indicated, the drawings are intended to be read together with the specification, and are to be considered a portion of the entire written description of this invention. As used in the preceding description, the terms “horizontal”, “vertical”, “left”, “right”, “up”, “down” and the like, as well as adjectival and adverbial derivatives thereof (e.g., “horizontally”, “rightwardly”, “upwardly”, “radially”, etc.), simply refer to the orientation of the illustrated structure.
The above description of embodiments of the invention should not be interpreted in a limiting manner since other variations, modifications and refinements are possible within the spirit and scope of the invention. The scope of the invention is defined in the appended claims and their equivalents.

## Claims

1. A sport helmet for protecting a head of a wearer, the sport helmet comprising:
a) an outer shell comprising an internal side and an external side; and
b) an inner pad mounted to the internal side of the outer shell for absorbing shocks when the sport helmet is impacted, the inner pad comprising:
i) a core of polymeric cellular material having an outer side facing towards the outer shell and an inner side for facing towards the head of the wearer, the core of polymeric cellular material comprising a body of expanded polymeric microspheres, each of the expanded polymeric microspheres comprising a polymeric shell expanded by a fluid encapsulated in the polymeric shell, wherein, in a longitudinal cross-section of the sport helmet, the core of polymeric cellular material occupies a majority of a thickness measured from the external side of the outer shell to the inner side of the core of polymeric cellular material; and
ii) a covering on the core of polymeric cellular material, the covering being arranged to cover at least part of the outer side of the core of polymeric cellular material and at least part of the inner side of the core of polymeric cellular material.

2. The sport helmet of claim 1, wherein the expanded polymeric microspheres have a size between 20 microns and 120 microns.

3. The sport helmet of claim 1, wherein a density of the expanded polymeric microspheres is less than 0.04 g/cm3.

4. The sport helmet of claim 1, wherein a density of the expanded polymeric microspheres is no more than 0.035 g/cm3.

5. The sport helmet of claim 1, wherein the core of polymeric cellular material has a periphery comprising the inner side and the outer side of the core of polymeric cellular material and the covering covers at least a majority of the periphery of the core of polymeric cellular material.

6. The sport helmet of claim 1, wherein the covering covers at least a majority of the inner side of the core of polymeric cellular material.

7. The sport helmet of claim 6, wherein the covering covers at least a majority of the outer side of the core of polymeric cellular material.

8. The sport helmet of claim 6, wherein the covering covers all of the inner side of the core of polymeric cellular material.

9. The sport helmet of claim 8, wherein the covering covers at least a majority of the outer side of the core of polymeric cellular material.

10. The sport helmet of claim 9, wherein the covering covers all of the outer side of the core of polymeric cellular material.

11. The sport helmet of claim 1, wherein the covering envelopes the core of polymeric cellular material.

12. The sport helmet of claim 1, wherein the covering comprises a fabric layer.

13. The sport helmet of claim 12, wherein the fabric layer is a non-woven fabric layer.

14. The sport helmet of claim 1, wherein the covering comprises a decoration.

15. The sport helmet of claim 14, wherein the decoration is a decorative pattern.

16. The sport helmet of claim 14, wherein the decoration is a sublimated decoration.

17. The sport helmet of claim 1, wherein the core of polymeric cellular material has a periphery comprising (i) the outer side and the inner side of the core of polymeric cellular material and (ii) a lateral side between the outer side and the inner side of the core of polymeric cellular material, and wherein the covering comprises a first covering portion and a second covering portion which meet at the lateral side of the core of polymeric cellular material such that the covering envelopes the core of polymeric cellular material.

18. The sport helmet of claim 1, wherein the core of polymeric cellular material is a first core of polymeric cellular material and the covering is a first covering, the inner pad comprising: a second core of polymeric cellular material having an outer side facing towards the outer shell and an inner side for facing towards the head of the wearer, the second core of polymeric cellular material comprising a body of expanded polymeric microspheres, each of the expanded polymeric microspheres of the second core of polymeric cellular material comprising a polymeric shell expanded by a fluid encapsulated in the polymeric shell; and a second covering which covers at least part of the outer side of the second core of polymeric cellular material and at least part of the inner side of the second core of polymeric cellular material.

19. The sport helmet of claim 1, wherein the outer shell comprises a first outer shell member and a second outer shell member movable relative to one another to adjust a fit of the sport helmet on the head of the wearer.

20. The sport helmet of claim 1, wherein the covering is bonded to the core of polymeric cellular material via a bond comprising an adhesive.

21. The sport helmet of claim 20, wherein at least part of the bond is between the covering and the outer side of the core of polymeric cellular material.

22. The sport helmet of claim 20, wherein the adhesive is a hot-melt adhesive.

23. The sport helmet of claim 20, wherein at least part of the bond is between the covering and the outer side of the core of polymeric cellular material and wherein the covering envelops the core of polymeric cellular material.

24. The sport helmet of claim 1, wherein the body of expanded polymeric microspheres constitutes more than 80% of the core of polymeric cellular material by weight.

25. The sport helmet of claim 1, wherein the inner pad contacts the internal side of the outer shell.

26. The sport helmet of claim 1, wherein the covering has a thickness of at least 0.05 mm.

27. The sport helmet of claim 1, wherein the inner pad comprises a ventilation hole, the ventilation hole extending through the core of polymeric cellular material and being defined by an interior surface of the core of polymeric cellular material that is at least partially covered by the covering.

28. The sport helmet of claim 27, wherein the outer shell comprises a ventilation hole aligned with the ventilation hole of the inner pad such that, in use, air circulates around the wearer's head when the helmet is worn and the wearer moves.

29. The sport helmet of claim 1, wherein the covering comprises a first portion made of a given material disposed on the inner side of the core of polymeric cellular material and a second portion made of the given material disposed on the outer side of the core of polymeric cellular material.

30. A sport helmet for protecting a head of a wearer, the sport helmet comprising:
a) an outer shell comprising an internal side and an external side; and
b) an inner pad mounted to the internal side of the outer shell for absorbing shocks when the sport helmet is impacted, the inner pad comprising:
i) a core of polymeric cellular material having an outer side facing towards the outer shell and an inner side for facing towards the head of the wearer, the core of polymeric cellular material comprising a body of expanded polymeric microspheres, each of the expanded polymeric microspheres comprising a polymeric shell expanded by a fluid encapsulated in the polymeric shell, the body of expanded polymeric microspheres constituting at least 85% of the core of polymeric cellular material by weight; and
ii) a covering on the core of polymeric cellular material, the covering being arranged to cover at least part of the outer side of the core of polymeric cellular material and at least part of the inner side of the core of polymeric cellular material.