Helmet shell structure

A helmet shell structure utilizing a first inner layer of epoxy resin shaped into a head covering of a desired size and configuration. A second layer of woven fabric is placed atop the first layer of epoxy. A third outer layer of epoxy resin is laid atop the second layer and is cured to a transparent state such that the second layer of woven fabric is visible through the third outer layer of cured epoxy.

BACKGROUND OF THE INVENTION 
The present invention relates to a novel and useful helmet shell structure. 
Helmets are now required for use with certain vehicles such as motorcycles, 
bicycles, and the like. In fact, it is often advisable to employ a helmet 
in many other situations where the possibility of head injury is eminent. 
Although helmets adequately protect the head of the user in most cases, it 
is important to make a visible inspection of a helmet after an impact has 
been received thereupon. Prior helmet structures have employed polymeric 
materials such as vinyl ester, and have included the provision of painting 
the outer surface of the same. Thus, the inner structure of such helmets 
is not visible to the user. 
A helmet structure which is impact resistant and easily inspected to 
ascertain its integrity would be a notable advance in the transportation 
field. 
SUMMARY OF THE INVENTION 
The present invention relates to a novel helmet shell structure. 
The shell of the present invention utilizes a first inner layer of epoxy 
resin which is shaped into a structure of a desired size and 
configuration. The first inner layer of epoxy resin is generally placed 
over a steel mold to achieve such desired shape. The first layer of epoxy 
may also be cured to a transparent or clear state. Of course, the mold and 
steel is waxed to allow release of the first layer therefrom. 
A second layer of woven fabric laid atop the first layer of epoxy. This may 
be accomplished when the epoxy is tacky or when it is completely hardened. 
The second layer of woven fabric may include strong materials such as 
KEVLAR, an aramid based polymer, carbon fiber, and the like. In addition, 
the second layer of woven fabric may be a combination of two or more of 
these materials. 
A third outer layer of epoxy resin is placed atop the second layer and is 
spread to a uniform thickness thereabove. Subsequent outer layers of epoxy 
resin may be employed as desired. In any case, the outer layer is cured to 
a hardened state in which it is transparent, allowing the user to visually 
inspect the second layer of woven fabric thereunder. Air bubbles are 
worked out of the outer layer by hand or through the use of an outer mold. 
In certain cases, a fourth layer of fiber glass material may be interposed 
the first layer and the second layer of woven fabric. It has been found 
that a fiber glass layer exhibits superior resistance to repeated impacts 
on the helmet. In many cases, the fabric elastic layer may be placed only 
along a portion of the helmet, especially over the ears and up the side 
portions of the helmet toward the top thereof. Again, the fiber glass 
layer would still permit the user to visually inspect the second layer of 
woven fabric. 
It may be apparent that a novel and useful helmet shell structure has been 
described. 
It is therefore an object of the present invention to provide a helmet 
shell structure which incorporates a layer of woven fabric therein which 
adds to the strength and durability of the helmet shell. 
Another object of the present invention is to provide a helmet shell 
structure which includes an outer layer of hardened epoxy material which 
is transparent to permit visual inspection of the woven layer of fabric 
within the helmet. 
A further object of the present invention is to provide a helmet shell 
structure which incorporates a woven fabric of great strength with a fiber 
glass layer to certain portions of the helmet shell in order to maximize 
impact resistance of the helmet shell. 
Another object of the present invention is to provide a helmet shell 
structure which exhibits great strength and is aesthetically pleasing to 
the user. 
The invention possesses other objects and advantages especially as concerns 
particular characteristics and features thereof which will become apparent 
as the specification continues.

For a better understanding of the invention reference is made to the 
following detailed description of the preferred embodiments thereof which 
should be taken in conjunction with the prior described drawings. 
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Various aspects of the present invention will evolve from the following 
detailed description of the preferred embodiments thereof which should be 
taken in conjunction with hereinbefore described drawings. 
The invention as a whole is depicted in the drawings by reference is 
character 10. The helmet shell 10 is generally shaped into a hemispherical 
configuration having a portion 12 which generally covers the head of the 
user and distending flanges 14 and 16 which cover the ears of the user. 
Referencing FIG. 2, it may be observed that shell 10 is formed by a first 
inner layer of epoxy resin 18 which is generally formed over a mold 
constructed of steel, composite, or other materials to produce the 
configuration and size of shell 10. In the normal course of molding, the 
mold is waxed to release first layer 18 therefrom when it has hardened. 
Shell 10 may be employed with face shields and fastening straps for use as 
a vehicle helmet. 
Also included in the present invention is a second layer 20 of woven fabric 
material which is positioned atop the first layer of epoxy. Second layer 
20 may take the form of strong artificial fibers, such as carbon fiber, 
KEVLAR, an aramid based polymer, combinations of these two, and the like. 
Second layer 20 may be placed above first inner layer 18 when first inner 
layer is tacky or when first inner layer 18 is completely cured, of 
course, second inner layer 20 may be fitted by cutting or shearing such 
material from a sheet of material as needed. 
Third layer 22 is laid atop second layer 20. Third layer 22 consists of an 
epoxy resin which is cured to a hardened transparent state. Thus, the user 
is able to look through third layer 22 after it is cured and observe the 
state of second layer 20 thereunder. Returning to FIG. 1, it may be 
apparent that a section 24 is illustrated in which second layer 20 is 
visible. However, it should be understood that illustrative section 24 is 
provided for the sake of clarity, since second layer 20 would be visible 
throughout helmet shell 10 when viewed from the outer surface thereof. In 
addition, epoxy resin from third layer 22 penetrates second layer 20 
during the curing process of third 22. Epoxy plugs 26, 28, and 30 are 
depicted on FIG. 2 to schematically represent such penetration. It has 
been found that epoxy flowing from third layer 22 through second layer 20 
completely saturates second layer 20 to form an integral shell 10. 
The structure of flange 16 is represented by FIG. 3 and includes first 
inner layer 18, second layer 20 and third outer layer 22 which are 
essentially identical to those depicted in FIG. 2. However, fourth layer 
32 has been added in the form of a fiberglass glass material. Dashed lines 
34 and 36 of FIG. 1 illustrate possible perimeters for the use of fourth 
layer 32. In other words, fourth layer 32 may be interposed first layer 18 
and second layer 20 beginning at the lower edge 38 of flange 16 and extend 
up to dashed line 34 or dashed line 36. Fourth layer 32 increases the 
impact resistance of helmet shell 10 in areas which are considered 
critical for protection during a crash. It should be noted that flange 14 
includes a similar structure to that shown for flange 16. Epoxy plug 40 is 
schematically representative of the penetration of the epoxy flowing from 
third outer layer 22, during the curing process, through second layer 20 
and fourth layer 32. Again, it should be realized that epoxy from the 
third layer 22 completely saturates second layer 20 and fourth layer 32 to 
form an integral flange 16 which is a portion of helmet shell 10. 
In operation, helmet shell 10 is formed by the provision of a first inner 
layer of epoxy resin 18 overlain by a second layer of woven fabric 20, and 
providing a third outer layer 22 of epoxy resin which cures to a hardened 
transparent state. An additional fourth layer 32 of fiber glass material 
may be interposed first layer 18 and second layer 20 in critical areas of 
helmet shell 10, i.e., at ear-protecting flanges 14 and 16. The user of 
helmet 10 wears the shell in the normal configuration when appropriate 
straps and face guards have been applied to shell 10. Second layer 20 is 
completely visible throughout the outer surface of helmet shell 10 and may 
be inspected for damage following any traumatic contact of helmet shell 10 
with an object. The sections of helmet 10 between the edges 38 and of 
flange 16 and the edge 42 of flange 14 upwardly to top 44 of helmet 10 may 
be further reinforced by fiber glass layer 32 to exemplary perimeters 34 
and 36. It has been found that helmet 10 is extremely strong and 
aesthetically pleasing as well as possessing the quality of allowing the 
user to inspect inner second layer 20 at all times. 
While in the foregoing, embodiments of the present invention have been set 
forth in considerable detail for the purposes of making a complete 
disclosure of the invention, it may be apparent to those of skill in the 
art that numerous changes may be made in such detail without departing 
from the spirit and principles of the invention.