US3480966A - Safety helmet retaining strap - Google Patents

Description

Dec. 2, 1969 5J. MOU-roms ET AL 3,480,966l

SAFETY HELMET RETAINING STRAP Filed Sept. 16, 1968 INVENTORS STEPHEN J. MOLITORIS DENNIS F. RNEY GERALD A. PARYLO ATTORNEYS United States Patent O 3,480,966 SAFETY HELMET RETAINING STRAP Stephen J. Molitoris, Ann Arbor, and Dennis F. Raney and Gerald A. Parylo, Detroit, Mich., assignor to American Safety Equipment Corporation of Michigan,

Oak Park, Mich.

Filed Sept. 16, 1968, Ser. No. 762,282 Int. Cl. A42b 1/08 ABSTRACT OF THE DISCLOSURE BACKGROUND OF INVENTION This invention relates to improvements in safety helmet retaining straps of the type disclosed in Patent No. 2,991,478 to Zbikowski and Patent No. 3,239,842 to Marchello. Inthese two prior patents, the safety helmet retaining straps are illustrated as being formed of a pair of V-shaped strap members whose lower ends are interconnected by chin strap sections and whose upper ends are secured to the safety helmet shell. These members tend to stretch upon impact to the helmet thereby permitting the helmet to move relative to the head of the wearer to an excessive degree at times. In addition, these members offer relatively little impact protection to the portions of the head which they cover.

SUMMARY OF INVENTION The object of this invention is to reduce or substantially eliminate the tendency to stretch and in addition, to provide impact protection to the V-shaped strap members disclosed in the above mentioned patents.

The invention herein contemplates forming such V- shaped strap members out :of an inner and outer sheet whose edges are sealed together to form a closed envelope containing a thick, resilient foam plastic cushioning layer and a thin, relatively stil, fabric sheet between the cushioning layer and the outer sheet. The fabric sheet being of a stretch resistant material, is secured to both the chin strap sections and the helmet shell to reduce the stretching of the retaining strap and at the same time, upon applied tension, forms a stiff backing wall for the cushioning layer to compress against for thereby absorbing impact energy, as well as increasing the ability of the member to resist penetration and abrasion due to side impacts.

These and other objects and advantages of this invention will become apparent upon reading the following description, of which the attached drawings form a part.

DESCRIPTION OF DRAWINGS FIG. 1 is a left side elevational view of a safety helmet shell and the improved retaining strap.

FIG. 2 is an elevational view of the right side retaining strap member.

FIG. 3 is a perspective view of the layers making up the retaining strap member.

FIG. 4 is an enlarged cross-sectional view taken in the direction of arrows 4 4 of FIG. l, and

FIG. 5 is an enlarged cross-sectional view taken in the direction of arrows 5--5 of FIG. l.

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FIG. 6 is an enlarged cross-sectional view taken in the direction of arrows 6--6 of FIG. 2.

DETAILED DESCRIPTION FIG. 1 illustrates a rigid safety helmet shell 10 which may be formed, as is conventional, of vfibrous glass reinforced resin with its lower edge covered by the usual rubber-like edge bead 11. FIG. 1 also illustrates the left side V-shaped strap mem-ber 12 and FIG. 2 illustrates the right side strap member 13, the two strap members being mirror images of each other and of the same construction.

The upper ends of the strap member are fastened to the shell by means of rivets 14 which pass through holes 15 (see FIG. 2) extended through the strap members.

Each strap member comprises an envelope 16 made of an outer sheet 17 and an inner sheet 18, both preferably formed of a heat sealable plastic sheet material which preferably is air impervious. The peripheral edges of the two sheets are heat sealed together to form edge seams 19.

The envelopes are stuffed with a thick, resilient foam plastic layer 20, which as shown in FIG. 3 is cut into the shape of the envelope but of slightly smaller exterior dimensions than the sheets 17 and 18.

Arranged between the layer and the outer sheet 17 are at least one and at times two or more thin sheets 21 fo-rmed of a relatively stift or starch-like fabric such as woven polyester or the like which is stretch resistant.

The -bights or lower ends of each ofthe members are interconnected by chin strap sections, such as chin strap section 23 to which is fastened a conventional buckle 24 illustrated in FIG. 1 and chin strap section 25 illustrated in FIG. 2, which connects to the buckle 24.

As shown in FIG. 6, the chin strap section 2S has an upper end 26 which passes through a slit 27 formed in the outer sheet 17 to lie between the outer sheet 17 and the fabric 21. Rows of stitches 28 fasten all the layers together and particularly mechanically secure the upper end of the chin strap section to the fabric. The upper end of the chin strap section 23 is fastened in a like manner to its V-shaped member.

As seen in FIG. 5, the fabric 21 is fastened to the helmet shell 10 by the same rivets 14 used to fasten the U-shaped members to the shell. Thus, when tension is applied to the retaining straps, as would occur upon impact to the helmet, the fabric resists the tendency of the straps to stretch to thereby prevent displacement of the helmet off the wearers head.

In addition, the members function as impact protecting means since, when tension is applied to the straps, the a1- ready relatively stiff fabric stiifens even further and forms a backing wall for the inner resilient layer which may then compress against it, that is, compress between the wearers head and the fabric so that the resilient layer and the fabric tend to absorb impact energy.

Preferably, the sheets are air impervious so that in effect the envelope is air sealed, despite the slit 27 which is substantially blocked off by the chin strap sections as Well as by the fabric sheets, particularly when tension is applied. Thus, a pneumatic cushion is also provided for more protection. When the straps are not under tension, such as when the helmet is not being worn, air can leak in or out of the envelope through the slit for ventilation purposes.

This invention may be further developed within the scope of the following claims. Accordingly, it is desired that the foregoing description be read as being merely illustrative of an operative embodiment of this invention, and not in a strictly limited sense.

Having fully described an operative embodiment of this invention, we now claim:

1. A head retaining strap for a rigid shell safety helmet comprising:

a pair of approximately V-shaped strap members depending from and located upon opposite sides of the shell, with the upper ends of the legs of the members arranged Within and secured to the shell by mechanical fastening means;

each member being formed of an outer and an inner sheet of flat, flexible plastic material whose adjacent edges are fastened together to form an envelope;

a thick layer of resilient foam material arranged between the sheets to stuif the envelope;

and al thin sheet of relatively stiff, stretch resistant fabric arranged between the layer and the outer sheet and substantially covering the layer;

and a chin strap section mechanically secured to the bight portion of each of said members, including being secured to the fabric at said bight portion, the fabric also being secured to the shell by said mechanical fastening means;

wherein the fabric resists the stretching of the retaining strap upon impact to the helmet and forms a stiff backing Wall against which the resilient layer compresses upon impact.

2. A construction as defined in claim 1, and the peripheral edges of said sheets being heat sealed together to 4 form a thick substantially air sealed, compressible envelope for absorbing impact energy.

3. A construction as dened in claim 2, and said outer layer being horizontally and centrally slit for approximately the width of said strap section at the bight of the member; t

and the chin strap section having an upper end passed into the slit and positioned between the fabric and the outer sheet and fastened to b oth the fabric and the outer sheet, so that upon applying Va vertical force to the retaining strap, the slitv is substantially sealed by the strap section and the fabric toy retain air in the envelope.

4. A construction as defined in claim 3, and said mechanical fastening means consisting of rivets passing through the strap members, including the two sheets, the layer and the fabric thereof, and secured to the helmet shell. A

References Cited UNITED STATES PATENTS 2,991,478 7/1961 Zbikowski 2,-3 3,239,842 3/ 1966 Marchello 2-3 3,327,316 6/1967 Pukish 2- 3 JAMES R. BOLER, Primary Examiner

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