# Patent

## Title
Surgical use of a laryngeal prosthesis

## Abstract

A pad structure for a protective headgear comprising, a resilient foam inner pad, a thin flexible front cover sheet of a foam material being formed into a configuration defining a cavity of a shape to closely receive and cover inner and side surfaces of the inner pad. The pad structure has a back cover sheet of flexible material covering a back surface of the inner pad and joined to the front cover sheet along bond lines adjacent a back portion of the inner pad and extending around sides of the inner pad.

## Background
This is a continuation-in-part of application Ser. No. 584,088, filed June 5, 1975, now U.S. Pat. No. 3,994,021.

The present invention relates to protective headgear and more particularly to pads for such headgear.

Before the present invention, protective pads have been proposed for use in headgear, such as football helmets, to prevent harm to the wearer's jaws during use of the helmets. In one form, such protective pads have been constructed from an inner pad which is located between two sheets of leather, the latter being sewn together along their sides. In an alternative form, the inner pad has been retained between two plastic sheets which are sealed together at their edges. However, in both cases the sheets do not readily conform to the shape of the inner pad resulting in a relatively unsightly protective pad which assumes a sausage-like configuration. The sheets either cover the inner pad too loosely or too tightly, and, in the latter case, undue stress is placed against the sheets by the inner pad, particularly during use of the helmet, resulting in seam splitting of the sheets. Moreover, such sheets are not sufficiently soft and conformable to provide the desired comfort for the wearer's skin.

The present invention relates to an improved pad structure for a protective headgear.

The pad structure of the present invention comprises, a resilient foam inner pad, a thin flexible front cover sheet of a foam material being formed into a configuration defining a cavity of a shape to closely receive and cover inner and side surfaces of the inner pad. The pad structure has a back cover sheet of flexible material covering a back surface of the inner pad and joined to the front cover sheet along bond lines adjacent a back portion of the inner pad and extending around sides of the inner pad.

A feature of the present invention is that the front cover sheet provides a soft and comfortable surface for the skin of the wearer.

Another feature of the present invention is that the formed front cover sheet fits the contour of the inner pad causing a reduction of stress between the front and back sheets.

Thus, another feature of the present invention is that the pad structure minimizes the possibility that the bond lines between the front and back cover sheets will become severed during use of the headgear.

Yet another feature of the invention is that the pad structure maintains a shape of improved appearance while providing improved comfort for the wearer.

Further features will become more fully apparent in the following description of the embodiments of this invention and from the appended claims.

In the drawings:

FIG. 1 is a side elevational view of a protective helmet or headgear;

FIG. 2 is a front elevational view of the helmet of FIG. 1;

FIG. 3 is a rear elevational view of the helmet of FIG. 1;

FIG. 4 is a bottom plan view of the helmet of FIG. 1;

FIG. 5 is a top plan view of the helmet of FIG. 1;

FIG. 6 is a sectional view taken substantially as indicated along the line 6--6 of FIG. 5;

FIG. 7 is an exploded perspective view of nestable liner for the helmet of FIG. 1;

FIG. 8 is a fragmentary sectional view of an upper central portion of one of the liners of FIG. 7;

FIG. 9 is a plan view of a retainer pad for the helmet of FIG. 1;

FIG. 10 is a sectional view of an embodiment of the retainer pad of FIG. 9;

FIG. 11 is a fragmentary inner view of a front portion of the helmet, and showing an end of a sweat band before being positioned inside of the helmet;

FIG. 12 is a fragmentary inner view of the helmet of FIG. 11 showing the sweat band as partially secured to an inner portion of the helmet;

FIG. 13 is a plan view of a jaw pad for the helmet of FIG. 1;

FIG. 14 is a sectional view of the jaw pad taken substantially as indicated along the line 14--14 of FIG. 13;

FIG. 15 is a fragmentary sectional view showing an embodiment of securing means for the jaw pad of FIGS. 13 and 14;

FIG. 16 is a plan view of a front pad for the helmet of FIG. 1;

FIG. 17 is a plan view of a rear pad for the helmet of FIG. 1;

FIG. 18 is a plan view of an upper retainer pad for the helmet of FIG. 1;

FIG. 19 is a fragmentary top plan view of a chin strap for the helmet of FIG. 1;

FIG. 20 is a fragmentary bottom plan view of the chin strap of FIG. 19;

FIG. 21 is a fragmentary sectional view of the chin strap taken substantially as indicated along the line 21--21 of FIG. 20;

FIG. 22 is a fragmentary sectional view taken substantially as indicated along the line 22--22 of FIG. 1;

FIG. 23 is a fragmentary sectional view of another embodiment of the helmet;

FIG. 24 is an exploded perspective view illustrating components used to make the pad of the present invention;

FIG. 25 is a fragmentary perspective view showing the inside of a formed sheet for the pad of the present invention; and

FIG. 26 is a sectional view illustrating the pad as formed by joining sheets.

Referring now to FIGS. 1-6, there is shown a protective helmet generally designated 30. Although the helmet 30 is shown in the form of a football helmet, it will be understood that the principles of the invention may be utilized in connection with any other suitable headgear, such as hockey helmets, baseball helmets, crash helmets, or other headgear where protection of the head is desired. As shown, the helmet 30 has an outer shell 32 which is preferably made of a relatively rigid material, such as a polycarbonate alloy, a rigid thermoplastic, or a thermosetting resin. The shell 32 has an upper central portion 33, a front portion 34, a rear portion 6, a lower front edge 38, a lower rear edge 40, and a pair of ear protectors 42. The shell 32 also has a plurality of ventilating apertures 44 extending through and spaced around an upper portion of the shell, and an opening 46 extending through the shell which will be further described below. As best shown in FIGS. 2-4, the shell 32 may include a region 48 of increased thickness in the longitudinal central area of the helmet or other area of the helmet, such as in the ear protectors 42, to provide additional reinforcement to the shell where holes may be placed in the shell.

The helmet 30 also has a flexible liner means or cradle 50 positioned in the shell 32 to dissipate forces applied against the helmet. Referring to FIGS. 6-8, the liner means 50 has a pair of first and second nestable flexible liners or cushions 52a and 52b, respectively. The first and second liners 52a and b respectively have a hollow annular member 54a and 54b adjacent an upper central portion of the respective liner, a plurality of hollow spaced spoke members 56a and 56b extending from and communicating with the annular member 54a or b of the respective liner, and a hollow rim 58a and 58b extending peripherally around a lower end of the respective liner and communicating with the respective spoke members 56a or b. As shown, side walls of the spoke members 56a and b and rims 58a and b define a plurality of openings 60a and 60b having the general shape of isosceles triangles extending through the respective liner. Also, the annular members 54a and b define generally circular shaped openings 62a and 62b extending through the upper central portion of the respective liner, with the sidewalls of the liners defining the openings 62a and b preventing overinflation or bulging of the upper central portions of the liners.

As best shown in FIGS. 6 and 8, the hollow first liner 52a defines first chamber means 64a communicating between the annular member 54a, the spoke members 52a, and the rim 58a. Similarly, the second liner 52b defines second chamber means 64b communicating between the annular member 54b, the spoke members 56b, and the rim 58b. In a preferred form, the first and second chamber means 64a and b of the first and second liners 52a and b, respectively, are inflated with a gas, such as air, although the second chamber means 64b of the second liner 52b may be filled with a liquid to provide additional rigidity to the second liner, if desired.

As best shown in FIG. 6, the first liner 52a is nested within the second liner 52b, with the spoke members 56a and b, annular members 54a and b, and rims 58a and b of the two liners 52a and b, as well as the first and second chamber means, being generally in alignment. In this configuration, the openings 60a and b and 62a and b of the two liners are also in alignment, such that the openings extend completely through the liner means 50. As will be seen below, the inner liner 52a defines a soft conformable inner surface 66a for contacting the wearer's head. As shown in FIGS. 4 and 6, the first liner 52a has lower valve means 68a of known type for inflating the first chamber 64a through the inside of the helmet, while the second liner 52b has upper valve means 68b for inflating the second chamber 64b through the opening 46 in the shell 32, as illustrated in FIG. 5. The first liner 52a may be removably positioned within the second liner 52b, and may be secured to the second liner, if desired, by suitable means, such as adhesive, hook and loop strips, or bands extending around the spoke members of the nested liners.

In a preferred form, the liners 52a and b are rotomolded, and are made from any suitable flexible or elastic material, such as polyvinyl chloride plastisol, ethylene vinyl acetate, polyethylene, or liquid polyurethane. Preferably, the inner first liner 52a has a durometer hardness less than the durometer hardness of the second liner 52b, although rigidity may be added to the second liner by filling it with liquid. in a suitable structure of the liners, the inner liner 52a has a shore A hardness in the range of 45-55, while the shore A hardness of the second liner 52b may be in the range of 75-90. If both liners are inflated with a gas, the modulus of elasticity of the inner liner is preferably less than that of the outer liner, such that the inner liner provides a relatively soft conformable inner surface 66a for contacting the wearer's head in a comfortable manner. The inner liner 52a readily compresses and absorbs energy in the helmet, while providing continued comfort to the wearer, resulting from impacts of relatively low force levels against the shell. The second liner 52b provides a more rigid structure to dissipate higher level forces applied against the shell. Thus, the liners 52a and b co-operate to absorb energy resulting from impacts against the shell of varying force levels, with the liners compressing or deforming differing amounts at the point of impact, such that the forces are dissipated in an improved manner to protect the wearer while providing continued comfort to the wearer.

Referring now to FIGS. 6 and 9, there is shown a plurality of resilient retainer pads 70 having a generally trapezoidal shape. The retainer pads 70 may be made of any suitable material, such as a closed cell polyvinyl chloride foam of medium density, for example, Ensolite, a trademark of Uniroyal, or, Rubatex, a trademark of Great American Industries. The pads 70 may have their outer surfaces treated to provide washable surfaces of the pads, for example, by dipping the pads in a suitable material, such as a liquid vinyl, urethane, or latex.

As illustrated in FIGS. 1-6 and 22, a plurality of the retainer pads 70 are positioned in the aligned openings 60a and b of the first and second liners 52a and b, with the enlarged portion of the pads being located adjacent the bases of the triangular shaped openings 60a and b. The pads 70 may be releasably attached to the inside of the shell 32 by suitable securing or fastening means 72 to maintain the pads 70 in place between the spoke members 56a and b of the first and second liners 52a and b. The fastening means 72 may comprise a hook and loop arrangement of known type, such as a pair of interengaging hook and loop strips 74a and 74b, with one strip 74a being secured to a back surface of the pads 70, and with the other strip 74b being secured to the inner surface of the shell 32. The pads 70 may be attached in the liner openings by passing the pads through the openings and engaging the strips 74a on the pads against the strips 74b on the shell to interengage the strips of the fastening means 72. The pads 70 may be removed from the openings by pulling on the upper ends of the pads to release the strips 74a on the back on the pads from the strips 74b on the inside of the shell.

As shown in the drawings, each of the retainer pads 70 extends betwen adjacent spoke members 56a and b of the liner means 50, such that the inclined sides of the pads abut against side walls of the spoke members defining the openings 60a and b of the liner means 50. Since the retainer pads 70 are secured to the shell 32, the pads prevent rotational movement or slippage of the liners 52a and b within the shell 32. Also, the sides of the pads 70 frictionally engage the spoke members 56a and b, and the pads 70 prevent upward movement of the shell 32 relative the liner means 50. Accordingly, the liners 52a and b are held firmly in place by the pads 70 within the shell. In this regard, it should be noted that the pads 70 extend a sufficient distance inwardly from the shell to engage side walls of the spoke members 56a of the inner first liner 52a, although the inner surfaces 76 of the pads 70 are spaced slightly from the inner surface 66a of the liner means 50.

The retainer pads 70 also confine the spoke members 56a and b of the first and second liners 52a and b at a location intermediate the pads 70. Thus, the pads limit the amount of expansion permitted by the spoke members intermediate the pads, and facilitate the liners in absorbing energy from an impact. When a force is applied against the shell, particularly in the region of the pads 70, the first and second liners 56a and b deform somewhat and the fluid in the chambers is compressed in the region of the impact. However, since expansion of the liners is confined in this area by the pads 70, deformation of the liners is reduced, and the liners provide greater impact resistance or cushioning effect in this region. Similarly, if the force is applied to an upper part of the shell 32, fluid passes from the region of the impact toward the lower portion of the liners, and the pads 70 limit expansion of the spoke members to obtain greater resistance to fluid compression in the region of the blow. In this manner, the retainer pads 70 provide additional buoyancy or resiliency to the liner means in order to dissipate forces applied against the shell.

As previously noted, the inner surfaces 76 of the retaining pads 70 are spaced slightly from the inner surface 66a of the first liner 52a. If a particularly hard impact is applied against the shell, such that the inner surface 66a of the liner 52a is depressed below the inner surfaces 76 of the pads 70, the retainer pads 70 then serve to absorb energy of the blow. In this case, the retainer pads 70 cushion the blow, and prevent the wearer's head from deforming the liners to a location adjacent the inner surface of the shell 32. In this manner, the first and second liners 52a and b and retainer pads 70 co-operate to absorb energies resulting from a blow to the helmet. At relatively low impact levels, the soft inner liner 52a cushions these blows without the inner surface 66a of the inner liner being depressed to a position below the inner surfaces 76 of the pads 70, although, in this instance, the second liner 52b may be slightly compressed and contributes in dissipating such forces. At higher level impacts, the more rigid second liner 52b provides a second level of energy absorption to dissipate such forces. If the impact is of sufficient magnitude, the inner surface 66a of the liner means 50 may be depressed below the inner surfaces 76 of the retaining pads 70 in the region of the blow, and the liners and pads 70 co-operate to absorb the great amount of energy from this blow. Since the pads 70 confine the spoke members 56a and b of the liners intermediate the pads, the pads cause a smooth transition of energy absorption by the liner means itself and by the liner means in combination with the retainer pads 70. Throughout this time, the inner liner 52a provides a soft cofortable surface for the wearer's head, and the retainer pads 70 are made of a relatively soft material to also provide a comfortable surface for the head when they are contacted as a result of a relatively hard blow to the helmet.

Another embodiment of the retainer pads is illustrated in FIG. 10, in which like reference numerals designate like parts. As before, the retainer pads 70' may have a generally trapezoidal shape, fastening means 72 for securing the pads to the inner surface of the shell, and a washable surface or coating. In this embodiment, the pads 70' have a first inner section 78 of relatively soft resilient material for contacting the wearer's head, such as the material described in connection with the pads of FIG. 9, and a second outer section 80 of relatively stiff resilient material. The section 80 may be made of any suitable material, such as a rubber and polyvinyl chloride foam composition, for example, a material distributed under the trademark De Cello by David Freeland and Associates, Inc. of Detroit, Mich. The pads 70' of FIG. 10 provide the helmet with a still higher level of energy absorption capability. When the pads 70' are contacted more lightly by the wearer's head, the relatively soft inner section 78 sufficiently absorbs shock in the helmet. However, when an extremely hard impact is applied against the shell and the wearer's head engages against the retainer pads 70' with a relatively high force, the second stiff sections 80 of the pads absorb energy from the blow, while the soft inner sections 78 of the pads cushion the wearer's head during the hard blow.

As illustrated in FIGS. 4, 5, 6, and 18, the helmet 30 also has a resilient pad 114 which is releasably positioned in the openings 62a and b of the liner means 50. The pad 114 may be made of any suitable material, such as the material described in connection with the retainer pads 70 or 70' above, and may have a suitable coating of washable material, as described above. The pad 114 and the shell 32 have suitable fastening means 116, such as the hook and loop strips discussed above, to releasably attach the pad 114 to the inside of the shell within the liner openings. The pad 114 may generally conform with the shape of the openings 62a and b, and may have a cutout 118 adjacent one end to facilitate removal of the pad 114 from the liner means. The upper pad 114 also serves to retain the liner means in its proper position within the shell 32, and to absorb energy from high level impacts against the helmet.

As best shown in FIGS. 1, 5 and 6, the upper ends of the retainer pads 70 are spaced from the annular members 54a and b of the first and second liners 52a and b, respectively, and define open regions 82 of the liner openings 60a and b. As shown, the ventilating openings 44 in the shell 32 communicate between the open regions 82 and the outside of the shell. Thus, air is permitted to circulate between the inside and the outside of the shell to ventilate the inside of the helmet while being worn.

As shown in FIGS. 1, 3, and 6, the rims 58a and b of the liner means 50 are spaced above the lower rear edge 40 of the shell 32. As shown in FIG. 17, an elongated rear sizer pad 84 is provided for placement in the lower rear portion of the shell. The pad 84 may be made of any suitable resilient material, such as the closed cell foam material described above in connection with the retainer pads 70 of FIG. 9, and may have a washable coating. The pad 84 preferably has a plurality of longitudinally spaced cutouts 86 to permit bending of the pad without wrinkling when placed in the shell. As shown in FIGS. 1, 3, and 6, the rear pad 84 is positioned below the liner means in the shell, and extends around a lower rear portion of the shell 32. The pad 84 may be releasably attached to the inner surface of the shell 32 by suitable fastening means 88, such as hook and loop strips, discussed above in connection with the pads 70, spaced longitudinally along the back surface of the pad and around the lower rear inner surface of the shell. Thus, the rear pad 84 is secured to the shell below the liner means 50 by pressing the pad against the shell to interengage the hook and loop strips of the fastening means 88. As shown, a lower portion of the rear pad 84 extends below the lower rear edge 40 of the shell 32. Thus, the pad 84 cushions the wearer's head and neck from an impact against a lower rear portion of the shell, and the lower portion of the pad 84 prevents the wearer's neck from engaging against the lower rear edge 40 of the shell. Since the rear pad 84 is normally in contact with the wearer's head or neck, the thickness of the pad may be selected or sized to the particular contour of a wearer's head, in order to provide a better cushioning effect against the shell.

Referring now to FIGS. 1, 2, and 6, the rims 58a and b of the first and second liners 52a and b are also spaced above the lower front edge 38 of the shell 32. As illustrated in FIG. 16, an elongated resilient front pad 90 is provided to cushion the wearer's head adjacent the lower front portion of the shell. The pad 90 may be made of any suitable material, such as the closed cell foam material described above in connection with the retainer pads 70. Also, the outer surface of the front pad 90 may be coated with a washable material, as previously described. As shown in FIGS. 1, 2, 6, and 16, the front pad 90 is releasably attached to the lower front portion of the shell by suitable fastening means 92, such as by hook and loop strips described above, with strips of the material being spaced longitudinally along the back surface of the pad 90 and the lower inner surface of the shell 32. Accordingly, the pad 90 is secured in place by pressing the pad against the lower front portion of the shell, such that the hook and loop sections or strips of the fastening means 92 interengage and retain the pad in place. In this configuration, the pad 90 is located below the liner means 50, and extends around the lower front portion of the shell, with a lower surface of the front pad 90 being located adjacent the lower front edge 38 of the shell. As shown, the pad 90 has a pair of depending tabs 94 adjacent its opposite ends, such that the tabs 94 cover a front inner portion of the ear protectors 42 of the shell 32. The thickness of the front pad 90 may be selected to conform with the particular size of the wearer's head, as described above in connection with the rear pad 84. Thus, the front pad 90 serves to absorb blows adjacent the lower front portion of the shell.

As shown in FIGS. 4 and 6, the helmet 30 has a sweat band 96 extending between the outside and the inside of the shell 32. The sweat band 96 may be made of any suitable material, such as a sheet of soft porous material which permits the transmission of water vapor through the sweat band. For example, the sweat band may be made from a poromeric polyvinyl chloride material having a reinforcement backing of woven material, such as a material sold under the trademark PORON by Rogers Corporation. As shown in FIGS. 1, 2, and 6, one end 100 of the sweat band 96 is received in an elongated U-shaped plastic retaining member 102, and the one sweat band end 100 and retaining member 102 are secured to the outside of the shell by suitable means, such as by a pair of spaced screws 104.

Referring now to FIGS. 11 and 12, the other end 106 of the sweat band has a pair of bifurcated tabs 108, with each of the tabs 108 having fastening means 110 for releasably attaching the tabs 108 to the fastening means 72 on the inside of the shell. The fastening means 110 comprises hook and loop strips which are compatible with the strips 74b on the inside of the shell, the latter being also utilized to secure the retainer pads 70 to the shell. As shown, the liner means 50 has aligned spoke members adjacent the front of the shell, with the fastening sections 74b under discussion being located in the liner openings on opposite sides of the front spoke members. As best shown in FIG. 12, the other end 106 of the sweat band 96 is secured in place by attaching the fastening means 110 of the tabs 108 to the fastening strips 74b on opposite sides of the front spoke members of the liner means. Next, a pair of retainer pads 70 may be positioned in the liner openings on opposite sides of the front spoke members, and are secured in place over the tabs 108 by interengaging the fastening sections 74a on the back surfaces of the retainer pads 70 against the fastening strips 74b on the inside of the shell 32. Thus, the pads 70 facilitate retention of the tabs 108 against the inside of the shell.

In this configuration, the sweat band 96 extends around the lower front edge 38 of the shell 32, the front pad 90, and the lower rims of the liner means 50, with the sweat band covering a portion of the front spoke members of the liner means, and with the tabs 108 of the sweat band 96 extending on opposite sides of the front spoke members. Accordingly, the sweat band 96 facilitates retention of the front pad 90 and the lower front portion of the liner means 50 in their proper place within the shell. As shown in FIGS. 6 and 11, the sweat band 96 also has a resilient pad 112 extending between the side edges of the sweat band, and being located intermediate the sweat band 96 and the lower front edge 38 of the shell 32. The pad 112 may be made of any suitable material, such as an open cell polyvinyl chloride foam. The pad 112 provides a cushion for the head over the lower front edge 38 of the shell.

Referring now to FIGS. 1, 2, 4, and 6, the helmet 30 has a pair of jaw pads 120 secured to the lower inner portion of the ear protectors 42 of the shell 32, with the lower surface of the jaw pads generally conforming with the lower edge of the ear protectors 42. The jaw pads 120 may be releasably attached to the ear protectors 42 by suitable fastening means 122, such as the hook and loop fasteners, discussed above, or male and female snap fasteners, as shown. Referring to FIGS. 13 and 14, the jaw pads 120 have an inner resilient pad 124 made of suitable material, such as open cell urethane foam. The pads 120 also have a front cover sheet 126 of a soft conformable material, such as a closed cell vinyl foam, and a back cover sheet 128 of suitable material, such as a sheet of vinyl, connected to the front sheet 126 adjacent sides of the pads 120. Thus, the front and back sheets 126 and 128 define an air chamber 130 covering the inner pad 124. As shown, the back sheet 128 has an opening 132, and the female fastener 134 of the fastening means 122 has an opening 136 extending through the fastener 134 and communicating with the opening 132 of the back sheet 128. Thus, air is permitted to pass through the fasteners between the chamber 130 and the outside of the jaw pads 120. Accordingly, the covered foam pads 124 are permitted to contract and expand during use of the helmet, and the fasteners 134 prevent the back sheet 128 from ripping or tearing around the back sheet openings 132.

Another embodiment of the fastening means 122 for the jaw pads 120 is illustrated in FIG. 15, in which like reference numerals designate like parts. In this embodiment, the fastening means 122 comprises a resilient fastening member 138. The fastening member 138 has a base 140 located inside the pad 120 behind the back sheet 128, and an enlarged outer head 142. Thus, the heads 142 of the fastening members 138 are passed through apertures 144 extending through the shell 32, until the heads 142 engage against the outer surface of the shell 32, and lock the jaw pads in place against the inner surface of the shell.

With reference to FIGS. 24-26, the jaw pads 120, or other suitable pad for the helmet, as desired, are constructed in the following manner. As shown in FIGS. 24 and 25, a sheet 200 of foam, such as a closed cell vinyl foam or urethane foam, is vacuum formed into a configuration having a raised portion 202 defining the cavity or chamber 130 for the inner pad 124. After placement of the pad 124 into the chamber 130, a second backing sheet 204 of a flexible material, such as vinyl, is placed against an inner surface 206 of the foam sheet 200, such that the pad 124 is enclosed in the chamber 130 between the sheets 200 and 204. Finally, with reference to FIG. 26, the sheets 200 and 204 are joined together along bond lines 208, such as by radiofrequency or heat sealing, and the outer portions of the sheets 200 and 202 are severed from the pad 120 along the cut lines 210 adjacent the bond lines 208. Of course, a single foam sheet 200 may contain a number of raised portions 202 such that a plurality of pads 120 may be simultaneously constructed from a pair of sheets 200 and 202.

It has been found that the foam cover sheet 126 provides a soft and comfortable inner surface of the pad 120 for the wearer's skin. Moreover, the pad 120 has an improved shape in contrast to prior jaw pads which assume a sausage-like configuration due to absence of such formation. Further, since the foam cover sheet 126 is formed to fit the inner pad 124, stresses between the front and back cover sheets are reduced, thus minimizing the possibility of splitting between the seams or bonds joining the sheets.

In a preferred form, the sheet 200 is made from closed cell vinyl foam, and may have a thickness of approximately 70 mils. As previously indicated, a preferred material for the sheet 204 is vinyl, and may have a thickness of approximately 18 mils. As shown in FIGS. 24 and 26, the inner pad 124 may have a relatively soft inner layer 212 and a relatively stiff back layer 214, such as the materials discussed above in connection with FIG. 10.

Referring now to FIG. 1, the helmet 30 also has a chin strap 146 to secure the helmet on the wearer's head. The chin strap 146 has a pair of retaining straps 148 and 150 which cross at lower space points to support a chin cup 152. As shown, ends of the straps 148 and 150 are slidably received in fastening elements 154 and 156, in order that the ends of the straps may be releasably secured to the outside of the shell at spaced locations to provide stability to the shell 32 when the helmet is worn. The distance between the chin cup 152 and the shell 32 may be modified by suitable adjustment of the straps 148 and 150 in the fastening elements 154 and 156.

Referring to FIGS. 19 and 20, the straps 148 and 150 may be secured together at the spaced crossing locations 158 and 160 by suitable means, such as by lines of sewing, and, the straps 148 and 150 are spaced apart in the region of the chin cup 152. The chin cup 152 has a sheet 162 of soft conformable material, such as the poromeric material described above in connection with the sweat band 96, extending between the spaced portions of the straps 148 and 150 in the cup. As best shown in FIG. 21, the lateral side margins 164 of the sheet 162 are folded over to a location against the straps, and the straps are secured to the sheet 162 and its side margins 164 by suitable means, such as by lines of sewing. THus, the sheet 162 has side edges 166 which extend past side edges 168 of the relatively stiff straps. Since the sheet 162 faces the wearer's skin, the side edges 166 of the sheet 162 define soft edges for contacting the wearer's chin and prevent the straps from cutting the wearer's skin during use of the helmet.

The helmet may be assembled in the following manner. The first liner 52a is positioned within the second liner 52b, and the nested liners 52a and b are placed in the shell, with one of the aligned spoke members being located adjacent the forward portion of the shell. Next, the front and rear pads 90 and 84 may be secured in place below the liners at the lower front and rear portions of the shell to temporarily retain the liners in their desired position within the shell. The other end 106 of the sweat band 96 may be passed around the front pad 90 and the lower hollow rims of the liners, and the bifurcated tabs 108 are secured to the inside of the shell on opposite sides of the front spoke members of the liners. Next, the retainer pads 70 are attached to the shell through the openings 60a and b of the first and second liners 52a and b to retain the liners in their proper position within the shell, and the pad 114 may be attached to the shell through the upper openings 62a and b of the liner means. Finally, the jaw pads 120 may be secured to the inside of the ear protectors 42 of the shell 32.

The helmet may then be fitted to the particular size of the wearer's head. First, the inner first liner 52a may be inflated through the valve means 68a from the inside of the helmet prior to placing the helmet on the wearer's head. The extent to which the inner liner is inflated may depend somewhat upon the size of the head relative the shell. Next, the helmet is placed on the wearer's head, and the helmet is secured in place on the head through use of the chin strap 146. Finally, the second liner 52b is inflated through the shell opening 46 and the valve means 68b from the outside of the shell while the helmet is secured on the wearer's head by the chin strap 146 to obtain a proper fitting of the helmet on the head. Thus, the second liner is inflated until the inner surface of the first liner contacts the head in a comfortable manner. In this manner, the inflatable liner means 50 and helmet may be adapted to varying head sizes. Of course, the helmet may be removed and the first inner liner may be inflated an additional amount if necessary to obtain a proper fit.

Another embodiment of the helmet 30 is illustrated in FIG. 23, in which like reference numerals designate like parts. In this embodiment, the helmet includes resilient connecting members 170 extending between the retaining pads 70, with the members 170 being located intermediate the liner means 50 and the shell 32. Thus, the pads 70 and connecting members 170 define a resilient third liner 174 having cutout portions 172 to receive the first and second liners 52a and b. The third liner 174 may be conveniently made of one-piece construction, for example, by molding the liner from a polystyrene foam or a radiated polyethylene foam, such that the retaining pads 70 project into the liner openings intermediate the spoke members of the liner means 50. The third liner 174 may have suitable cutouts to receive the spoke members, the annular members, and the rims of the first and second liners, as desired. Thus, the third liner 174 retains the inflatable first and second liners in position within the shell, and confines expansion of the liner means intermediate adjacent pads, in a manner as described above. Of course, the connecting members 170 of the third liner 174 provide additional energy absorbing capacity for the helmet intermediate the liner means and the shell 32.

The foregoing detailed description is given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, as modifications will be obvious to those skilled in the art.

## Claims

1. Protective headgear, comprising: cover sheet of a foam material being formed into a configuration defining a cavity of a shape to closely receive and cover inner side surfaces of said inner pad, and a back cover sheet of flexible material covering a back surface of said inner pad and joined to said front cover sheet along bond lines adjacent a back portion of the inner pad and extending around sides of the inner pad; and

2. The headgear of claim 1 wherein said front cover sheet comprises a closed cell foam.

3. The headgear of claim 2 wherein said front cover sheet comprises a closed cell vinyl foam.

4. The headgear of claim 1 wherein said back cover sheet comprises a vinyl.

5. The headgear of claim 1 wherein the pad means comprises a jaw pad.

6. The headgear of claim 1 wherein said front and back cover sheets are sealed together along said bond lines adjacent the back surface of the inner pad.

7. The headgear of claim 1 wherein the attaching means comprises fastening means for releasably attaching the back sheet of the pad means to the helmet, said back sheet and fastening means having opening means extending through the fastening means and back sheet to the pad, said opening means being normally open and communicating between the cavity and atmosphere to permit free passage of air between the pad and atmosphere.