US2423076A

US2423076A - Method of making helmets

Info

Publication number: US2423076A
Application number: US474867A
Authority: US
Inventors: Daly Le Grand
Original assignee: Individual
Current assignee: Individual
Priority date: 1943-02-05
Filing date: 1943-02-05
Publication date: 1947-07-01
Anticipated expiration: 1964-07-01

Description

METHOD OF MAKING HELMETS Filed Feb. 5, 1945 2 Sheets-Sheet 1 m x f'dfizfldg,

QY a a ATTORNEY July 1, 19 47. LE GRAND DALY METHOD OF MAKING HELMETS Filed Feb. 5, 1943 2 Sheets-Sheet 2 Patented July 1, 1947 UNITED s'rArss PATIENT OF'FlCE'j Le Grand Daly, Birmingham, Mich.

Application February 5, 1943, Serial No. 474,867

1 This invention relates to helmets made from 1 plastic impregnated cloth, paper or fabric, and

more particularly to an improved method of making safety helmets such as may beused by firement or air raid wardens. The present application is a continuation-in-part of my copending application for Molding method and apparatus,

/ Serial No. 433,943, filed on March 9., 1942.

One of the objects of the present invention is to provide an improved method of making safety helmets from plastic impregnated fabrics in a speedier and more convenient manner.

Another object of the invention is to provide an improved method of making safety helmets built up to approximate shape from a plurality of plastic treated pieces of fabric and thereupon molded to final shape under the action of heat and pressure, or pressure only.

A further object of the invention is to provide an improved method of making helmet-s specified in the preceding paragraph, in accordance with which a helmet is made up of as few pieces as possible, is light and strong, and in which helmet the sections liable to be subjected to higher stresses and strains are correspondingly reinforced. i

A still further object of the invention is to provide an improved method of making helmets, in accordance with which a helmetis molded from a plurality of plastic treated pieces of fabric, has a crown strong enough at its top to withstand a maximum impact load which the helmet wearers neck can take, the sides of the crown being strong enough to support the crown top under such load and to transmit the load to the headcontacting supporting structure of the helmet.

A still further object of the present invention is to provide an improved method of making safety helmets molded from a plurality of plastic treated fabric pieces, the number of said pieces being reduced to a minimum to effect saving in dies and to facilitate manufacture, the individual pieces being of such respective shapes that waste of material is prevented.

A still further object of the present invention is to provide an improved helmet molded from a plurality of plastic treated fabric pieces, the shape of individual pieces and their arrangement in the helmet being such that seams are mutually staggered and yet no thick portions having excess of material are formed in the helmet.

A still further object of the present invention is to provide an improved helmet molded from a plurality of plastic treated fabric pieces, which helmet has a relatively wide brim, the character 7 6 Claims. (01. 2

2 g a .oi the individual pieces being such that no seams are present in the brim and moreover no distortion of the material of the brim andfchanges in the size thereof take placein molding, whereby the necessity of trimming of thehelmet blank after molding may be eliminated.

A still further object of the present invention is to provide an improved helmet molded from a plurality of plastic treated fabric pieces, the character of the individual pieces and their arrangement in the helmet being such that in addition to satisfying the objects andrequireinents listed above, they also insure easy handling of "preforms," i. e., assembled but not yet molded hel mets, as well as going of said pre-forms" into the molding dies without bending or moving any pieces from their respective places in "preforms," thereby preventing formation of wrinkles and folds.

It is an added object of the present invention to provide an improved helmet of the foregoing character which is of a strong, and dependable construction, which is safe and comfortable in use, and is relatively inexpensive to manufacture. Other objects and advantages of the present invention will be apparent from the following description and the appended drawing forming a part of the present specification, in which drawing similar numerals refer to similar parts. throughout theseveral views.

In the drawings: Figure 1 is a perspective view illustrating a helmet embodying the present invention.

Figure 2 is a bottom view or the helmet of Figure 1. a Y

Figure 3 is an exploded view showing a set of pieces of material for one helmet.

Figure 4 is a perspective view of a pro-form, i. e., assembled set of fabric piecesbeiore molding. Figure 5 is a longitudinal sectional view of a helmet shell after molding, the thickness of fabric being somewhat exaggerated for the sake of clarity, and 1 Figure 6 isa perspective view illustrating a 45 helmet with a neck protecting apron.

Before explaining in detail the present invention, it is to be understood that the invention is capable of other embodiments and modifications and that the terminology and phraseology 50 employed herein is for the purpose oi. description and not of limitation, and it is not intended to limit the invention beyond the requirements of the prior art.

In the drawings there is shown, by way of 65 example, an improved helmet embodying the present invention. The helmet construction herein illustrated and described is particularly suitable for air-raid warden duty; however, it will be understood that the present invention can also be embodied into helmets intended for other uses, such as forwork in mines, quarries, building constructions, in farm work, and in various sports. It should also be understood that the term plastic" as used herein includes various thermosetting and thermoplastic materials which may be used in connection with fabric or fabric reinforcements and molded by application of heat and pressure or pressure alone. It should be further understood that the term "fabric as it is used in th specification and claims is intended to designate a common textile material woven to a flat shape on a loom,

and particularly a material possessing strength but substantially unstretchable, such as carivas or duck cloth. The term is not intended to include knitted materials which are stretchable and therefore do not present any difiiculties in forming to curved shapes; similarly, the term fabric is not intended to cover pieces individually knitted or woven to approximate helmet shapes. Moreover, the term fabric" as herein used does not refer to glass fiber materials which are easily shaped to various curved forms due to relative slippage of fibers. Generally the present invention is directed to utilization of relatively inexpensive substantially unstretchable materials.

Referring more particularly to the drawings, the helmet illustrated therein comprises generally a shell l0, having a crown II and a brim I2 merging smoothly into each other. To the shell it there is secured in any suitable way, such as with the aid of rivets IS, a head-contacting structure, generally indicated by the numeral I 4. Said structure I4 is made of a plurality of interconnected straps and is adapted to support said shell H) on the wearers head without permitting the shell to contact the head of the wearer. An adjustable chin strap 15 is provided as shown in the drawings. The edges of the brim portion l2 may be provided with a trimming strip l8.

Figure 3 illustrates a set of plastic treated pieces from which the shell 10 is molded, said pieces being shown fiat, i. e., as they come out of the cutting dies and before they are assembled together on a form block into an approximate shape of the helmet, as shown in Figure 4. Said set comprises, first, two brim pieces 20 and 2| of a rounded configuration and having integral peripheral portions 20a and 2la, and a plurality of converging tongues or sectors 20b and 2lb, projecting inwardly from said portions 20a and 2la, respectively, and made by slitting the material as illustrated.

The set further includes two crown pieces 25 and 28 also of a substantially rounded configuration and comprising central integral portions 25a and 26a and a plurality of diverging tongues 25!) and 26b projecting outwardly from said portions 25a and 28a, respectively, and made by slitting the material of the peripheral portions of the pieces as shown.

It is preferable to use two brim pieces and two crown pieces. However, under certain conditions using only one brim piece and one crown piece, or more than two of each may be advantageous.

The set illustrated in Figure 3 includes further two dome reinforcing pieces both designated by the numeral 21, since they may be identical in size and shape. It is preferable to make them of square outline to prevent waste of material. A single strip 28 of the length equal to length of the peripheral edge of the brim l2 may also be provided if it is desirable to have a trimmed edge on the brim as illustrated at It in the drawings.

The pieces of Figure 3 may be cut out in any suitable manner. For quantity production they may be stamped out in several layers in suitable dies.

Prior to molding, the pieces shown in Figur 3 are first assembled together on a form block into a pre-form i. e., an approximate shape of the helmet. Such a pre-form" is shown in Figure 4. In assembling the pieces, the brim pieces are first put on the block which has the shape of the helmet, the crown of the block bending the wedges 20b and 2"; upwardly. Thereupon one of the

piece

25 or 26 is placed on the form block, with its central portion arranged on the top of the block crown, and the tongues thereof are bent downwardly and arranged to overlap each other at their lower portions. The dome reinforcing pieces 21 are then laid down on the top of the crown piece in a star-like arrangement, as shown in dotted lines in Figure 4. Such an arrangement gives double layer reinforcement which tapers into single layer tongues, thereby insuring better transition from thicker to thinner sections of the shell, smoother surfaces and better distribution of stresses in a helmet. Thereupon the second crown piece is laid on the dome-reinforcing pieces 21 arranged as explained, and its tongues are also bent downwardly. The pieces so as sembled are loosely connected in any suitable manner to insure their remaining in place during transfer of the pre-form into the molding dies. It is preferable to effect such connecting by touching the pre-form" in places with a hot soldering iron. If a trimming strip such, for instance, as one shown at 28 is provided, the same is bent longitudinally and is arranged around the edges of the brim; it may be temporarily held in place with the aid of clips 29 for more convenient handling.

It is desirable that seams formed at the places of juncture of tongues 20b, 2"), 25b and 261) do not register with each other but are staggered to produce a stronger construction. This may be achieved in several ways. For instance, the pieces 20 and 2|, as well as

pieces

25 and 26, may be slightly offset in the process of assembling the pre-form." Also, the number of tongues on a piece may be made odd and one of the identical pieces produced in the same die turned over before being superimposed on another piece.

Molding of the "pre-form may be effected in a number of ways and apparatus. It is preferable to use the method and the apparatus described in detail in said copending application Serial No. 433,943. Briefly, such molding comprises subjecting a pre-form" to forming pressure in a heated mold. The female part of the mold may be made of a pressed sheet metal sample helmet, while the male part or punch thereof may be in the form of an expandable rubber member.

Figure 5 illustrates a helmet shell after the same is molded, the thickness of separate fabric layers being somewhat exaggerated for the sake of clarity. With the process and the apparatus as mentioned, the outside surface of the shell comes out very smooth and glossy, while the unevenness in the thickness of the shell is taken care of not by crushing the high spot but by permitting them to proiect'somewhat from the inside surface of the shell.

After the molding operation, the supporting structure l4 and the chin strap are riveted 6 from the inside thereof, and molding said pieces together to form a unitary helmet shell structure.

3. In a method of making a helmet from plastic treated fabric, the steps of providing a set of to the shell. Thereupon the shell may be painted r in a desired color. For air raid warden use, it is preferable to spray the shell with white enamel and to paint desired insignia thereon.

Due to the fact that the integral peripheral portions a and 2m of the brim pieces 20 and 2| are-not distorted or bent in the process of forming and molding, trimming of the edges of the brim of the finished shell may not be necessary, which is a great advantage in manufacturing. In fact, the provision of the trimming strip "5 may be dispensed with under certain conditions, and the edges of the brim be finished simply by sanding.

Due to the fact that tongues 20b and 2lb of the brim pieces are arranged on the inside surface of the shell and are bent toward the top of the crown, while the tongues band25b of the crown pieces are arranged on the outside surface of the shell and are bent away from the top of the crown, handling of the pre-form in molding is greatly facilitated, and the action of the die and punch members of the molding die operates to smoothen and to wipe down said tongues and to distribute them evenly in the shell, rather than to bend their tips or to form wrinkles near their roots. The above feature constitutes an important improvement.

Figure 6 shows a helmet substantially identical with that shown in Figures 1-5, but provided with a neck protecting apron 3U. Said apron may be made of any suitable material, such as waterproof canvas or oil cloth and secured to the shell similarly or even in the same operation with the supporting structure ll. The function of the apron is to protect the neck of the wearer from water, heat and sparks. It is preferable to make the apron of such a size and outline that, if desired, it may be bent into the shell and so arranged therein and the helmet may be worn with said apron forming an additional protection to the wearers head.

By virtue of the above described improved helmet construction the above listed objects of the present invention, as well as numerous additional advantages, are attained.

I claim:

1. In a method of making a helmet from plastic treated fabric, the steps of providing a set of fiat fabric pieces, said set including at least one substantially round crown piece foldable into an approximate form of the crown, and at least one brim piece having an integral peripheral brim portion and a radially slitted central portion forming wedge-shape tongues, assembling said pieces in helmet form with said tongue overlapping said crown piece from the bottom edge thereof toward the top or the crown, and molding said pieces together to form a unitary helmet shell structure.

2. In a method of making a helmet from plastic treated fabric, the steps of providing a set of fiat fabric pieces, said set including at least one substantially round crown piece foldable into an approximate form 01' the crown, and at least one brim piece having an integral peripheral brim portion and a radially slitted central portion forming wedge-shaped tongues, assembling said pieces in helmet form with said tongues overlapping the depending portion of said crown piece flat fabric pieces, said set including a plurality f crown pieces each having an integral central portion and a plurality of tongues projecting therefrom, said crown pieces being foldable into an approximate form of the crown, and a plurality of brim pieces each having an integral peripheral brim portion and a plurality of tongues projecting inwardly therefrom, assembling said crown and brim pieces in helmet form with the tongues of the brim pieces overlapping the tongues of said crown pieces, and molding said pieces together to form a unitary helmet shell structure."

4. In a method of making a helmet from plastic treated fabric, the steps of providing a set of flat fabric pieces, said set including a plurality of crown pieces of substantially round shape slitted outwardly from an integral central portion, a number of dome reinforcing pieces, and a plurality of brim pieces of substantially round shape slitted inwardly from an integral peripheral brim portion to form inwardly extending tonguespbringing said crown pieces to approximated shape offthe crown with said dome-reinforcing pieces disposed between them, assembling said crown and said brim pieces in helmet form with their slitted portions overlapping, and molding the assembled pieces together to form a unitary helmet shell structure} 5. In a method of making a helmet from plastic treated fabric, the steps of providing a set of flat fabric pieces, saidset includih'gat least one substantially round crown piece slitted outwardly from an integral central position and foldable into an approximate form of the crown, and at least one brim piece having an integral peripheral brim portion and a radially slitted central portion forming wedge-shape tongues, and a brim edge trimming piece; assembling said pieces in helmet form with the slitted portions of said crown and brim pieces overlapping, and said brim edge trimming piece embracing the edge of the brim; and molding said assembled pieces together to form a unitary helmet shell structure.

6. In a method of making a helmet from a plastic treated substantially unstretchable flat material, the steps of cutting from a flat sheet of plastic treated material a substantially round brim piece having an unbroken outer edge and a slitted middle portion, and a substantially round crown piece having an integral central portion and a slitted peripheral portion, assembling said pieces to an approximate form of helmet with s 8 .id slitted portions overlapping each other, and molding them together to form a unitary helmet shell structure.

LE GRAND DALY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS