US 3621841 A
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Description (OCR text may contain errors)
Nov. 23, 1971 H. w. AUSTIN FTAL FOLDABLE PROTECTIVE HEAD ENCLOSURE,
2 Sh00tsShu-ct 2 Filed May 14, 1970 V E 'd M m n v F /x l 7. E T: m a 5 ul hl l H. W. AUSTIN ETA!- Nov. 23, 1971 FOLDABLE PROTECTIVE HEAD ENCLOSURE Filed May 14, 1970 United States Patent 3,621,841 FOLDABLE PROTECTIVE HEAD ENCLOSURE Harry W. Austin, Monroeville, John C. Miller, Pittsburgh, Rutherford B. Snyder, Jr., Bradford Woods, and John W. Neidhart, Mouroeville, Pa., assignors to Mine Safety Appliances Company, Pittsburgh, Pa. Filed May 14, 1970, Ser. No. 37,135 Int. Cl. A62h 17/04 US. Cl. 128-142.7 6 Claims ABSTRACT OF THE DISCLOSURE A protective hood for the head has a front window formed from a sheet of flexible plastic provided with a central outlet opening in front of the mouth and inlet openings at each side of the central opening. Secured to the window is an outlet valve surrounded by a breathing tube that extends rearwardly for insertion in the mouth. Each inlet opening is closed by a filter, and a cover has an upright body spaced behind the filters and valve and also has forwardly extending walls sealed to the inner surface of the window around the openings as a group. This cover body is provided with an opening through which the breathing tube extends, and the tube has a lateral inlet opening between the cover body and the window for establishing communication between the inside of the tube and the air duct formed by the cover. At opposite sides of the tube opening in the cover it has hinged portions to permit the cover and window to be folded rearwardly on opposite sides of the breathing tube when not in use.
The invention herein described was made in the course of, or under, a contract or subcontract thereunder with the Department of The Air Force. Protective head enclosures or hoods, usually worn with protective suits, protect against extreme heat and/or noxious chemicals. When protecting against chemicals, such as chemical warfare agents, air purifying apparatus also must be Worn. Although a gas mask could be worn inside the hood, this requires a bulkier hood and also makes it necessary to carry and put on the extra mask. It would be desirable to have the hood and mask combined into a single unit, but heretofore that would have interfered with the hood being folded in order to occupy little space when it is not in use so that it conveniently can be carried by a person for use in an emergency.
It is among the objects of this invention to provide a protective head enclosure, in which a hood also serves as a breathing mask, and in which the hood and the breathing components attached to it can be folded when not in use.
The preferred embodiment of the invention is illustrated in the accompanying drawing, in which FIG. 1 is a front view of the head enclosure;
FIG. 2 is a side view;
FIG. 3 is an enlarged horizontal section of the front of the enclosure, but showing it in a flat plane;
FIG. 4 is a fragmentary inside or rear view of the front of the enclosure; and
FIGS. 5 and 6 are enlarged vertical sections taken on the lines V-V and Vii-VI, respectively, of FIG. 4.
Referring to FIGS. 1 and 2 of the drawings, a hood 1 formed to surround the head is formed from flexible impervious material, preferably aluminized nylon film. The bottom of the hood may be designed to be sealed around the neck or it may be sealed to the collar of a complete protective suit. The front of the hood is provided with a large and generally rectangular opening 2 that is covered by a sheet of transparent plastic 3 sealed 3,6Zl,84l Patented Nov. 23, 1971 to the wall of the opening. This window gives good visibility to the'person wearing the hood.
As shown in FIGS. 3 and 5, the window is provided with an outlet opening 4 that is located in front of the mouth of the wearer. It also is provided with an inlet opening 5 a each side of this central opening. Mounted in the central opening is an outlet valve that includes a flanged cup 6 sealed to the wall of the opening. The back of the cup has several spaced holes in it that are normally closed by a flexible rubber disc 7, the central portion of which is anchored in the cup. Air can pass outwardly through the valve but not inwardly.
Surrounding this valve is the large front end of a breathing tube 9. The rear portion of the tube is reduced in height materially to form an oval portion that can be held in the month by means of a conventional resilient bitepiece 10 mounted on the tube. Although the nose may be closed by a separate clamp, it is preferred to close it with a resilient clip '11 (FIG. 5) integral with a post 12, the lower end of which surrounds the breathing tube in front of the bitepiece. The tube therefore holds the clip in position when the bitepiece is in the mouh.
Each of the inlet openings 5 in the window is closed by a filter. This preferably is done by mounting the filter 14 in a case 15 that fits snugly in the inlet opening. The front of the case is open to receive the filter, but the back of the case inside the hood is closed except for a port or two that are closed during exhalation by a rubber flap 16 supported by studs 17 projecting from the back of the case, as shown in FIGS. 3, '4 and 6.
Visibility through the window can be improved by making the inlet openings and the filter cases substantially in the form of right triangles, with one leg of each triangle at the bottom and substantially horizonal, and wih the hypotenuse inclined upwardly and outwardly from the inner end of the bottom leg. As shown in FIG. 1, this provides more space between the tops of the filters than between their bottoms.
To permit air to be inhaled through the breathing tube 9, it is provided with a lateral inlet opening 19 at each side of the outlet valve. Air entering the hood from the filters is confined in a duct that communicates with these openings. This duct is formed between the window and the upright body 20 of a cover spaced behind the filters and valve and having forwardly extending peripheral walls 21 surrounded by integral flanges 22 sealed to the inner surface of the window around the group of three openings therein. The cover is provided with an opening 23, through which the reduced rear portion of the breathing tube 9 extends and in which it is sealed. The cover also serves to hold the breathing tube in position around the outlet valve. It is stiff enough to maintain is shape without collapsing, but for a reason that will soon appear it is made of a material, such as a plastic, that can be folded and unfolded with little effort and without damage to it. Zlnhalation through the breathing ube draws air through the filters and into the duct formed by the cover, whe exhalation forces air straight out through he cenral exhalation valve.
Of course, there is no problem is folding the hood to bring the back portion forward against the air filtering system and the window, but the folded hood would still be as wide as the window and that is too wide for packaging in a small case to be carried by the user. It is therefore a feature of this invention that the window 3 can be folded upon itself against the opposite sides of the breathing tube to reduce the width of the window by nearly half. Accordingly, as shown in FIGS. 3 and 4, the cover that forms the air duct has hinge portions at opposite sides of the tube so that the cover can be folded rearwardly with the window. The hinge portions may be formed by molding crimps into the cover at opposite sides of the breathing tube. Thus, the upright body 20 of the cover is provided with forwardly directed crimps 25 extending from top to bottom of it. The sides of each crimp meet at substantially a right angle along their front edges, and that is the point or line along which the hinging occurs. Also, to prevent the upper and lower peripheral walls 21 of the cover from interfering with folding of the cover, they are provided with vertically directed crimps 26 at the upper and lower ends of the other crimps 25. Consequently, although the cover normally is a stitf member, it can be folded at the crimps when desired and this permits the head gear to be flattened to take up less room when not in use.
According to the provisions of the patent statutes, we have explained the principle of our invention and have illustrated and described what we now consider to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.
1. A protective head enclosure comprising a flexible hood adapted to totally enclose the head of a user, said hood having a window formed from a sheet of flexible transparent plastic, the window being provided with a central outlet opening, the window also having inlet openings at each side of the outlet opening, an outlet valve for the outlet opening secured to the window, a breathing tube surrounding said outlet valve and extending in teriorly therefrom for insertion in the mouth, a filter closing each inlet opening, and a relatively rigid cover means spaced behind said filters and outlet valve and having forwardly extending peripheral walls sealed to the inner surface of the window around said inlet and outlet openings to form an air duct, said cover means being provided with an aperture receiving the breathing tube, said tube having a lateral innlet passageway between said cover means and window establishing communication between the inside of the tube and said duct, and the cover means having substantially vertical hinge portions at opposite sides of said aperture to permit the cover means and window to be folded on opposite sides of the breathing tube when not in use.
2. A protective head enclosure according to claim 1, in which each of said hinge portions of the cover means includes a forwardly directed crimp extending from top to bottom of said cover means.
3. A protective head enclosure according to claim 1, in which each of said hinge portions of the cover means includes a forwardly directed crimp extending from top to the bottom of said cover means, and vertically directed crimps in said peripheral walls at the upper and lower ends of said first-mentioned crimp.
4. A protective head enclosure according to claim 1, in which said inlet openings are substantially right triangles with one leg of each triangle at the bottom and substantially horizontal and with the hypotenuses of the two triangles diverging upwardly from the inner ends of the horizontal legs.
5. A protective head enclosure according to claim 1, including filter cases extending interiorly from said inlet openings and containing said filters, said cases being sealed against the window and provided in their backs with ports, and inlet valves carried by the cases for closing said ports during exhalation.
6. A protective head enclosure according to claim 1, including a bitepiece mounted on the interior end of the breathing tube, and a nose clip mounted on said tube and extending upwardly therefrom for closing the nose.
References Cited UNITED STATES PATENTS 703,948 7/1902 Muntz. 1,395,948 11/1921 Drager. 1,978,994 10/ 1934 Fortunato. 2,706,983 4/1955 Matheson et al. 3,098,233 7/ 1963 Hoagland.
RICHARD A. GAUDET, Primary Examiner J. B. MITCHELL, Assistant Examiner