US 2999498 A
Descripción (El texto procesado por OCR puede contener errores)
Sept. 12, 1961 J. N. MATHESON 2,999,498
RESPIRATOR Filed May 7, 1957 2 Sheets-Sheet 1 v INVENTOR.
Sept. 12, 1961 J. N. MATHESON 2,999,498
RESPIRATOR Filed May 7, 1957 2 Sheets-Sheet 2 INVENTOR. Mesflfllllzesorz.
United States Patent 2,999,498 RESPIRATOR James N. Matheson, Reading, Pa, assignor, by mesne assignments, to The Electric Storage Battery Company, Philadelphia, Pa., a corporation of New Jersey Filed May 7, 1957, Ser. No. 657,671
Claims. (Cl. 128--146) This invention relates to an industrial respirator for filtering dust and obnoxious fumes and, more particularly,
to a respirator face piece having replaceable filters and which is adapted to surround the nose, cheeks and chin of the wearer. This is a continuation-in-part of my copending application Serial No. 430,488 filed May 18, 1954, .now Patent No. 2,858,828. 7
An outstanding disadvantage of common types of industrial respirator face pieces is that they include inhalation valves which offer appreciable resistance to breathing, therefore tire the wearer.
Another disadvantage is that the exhalation valve sometimes becomes leaky because of the failure ofthe valve diaphragm to become securely seated on the valve seat, particularly when there are imperfections either in the diaphragm or seat or when dust particles are introduced between the diaphragm and seat.
An object of my invention is to provide a novel res pirator face piece which is devoid of the above named disadvantages and which includes inhalation valves which provide minimum breathing resistance and will assure a positive seal of the valve even in the event there are imperfections in the valve diaphragm or seat or if dust particles are introduced therebetween.
A more specific object of my invention is to provide anovel inhalation valve mounting for the valve diaphragm for easy flexing to the open position on inhalation, and which will assure an air-tight seal with the 'valve se'at minimum resistance to exhalation as well as quick and positive seating in an air-tight manner'upon inhalation of the wearer even in cases where there are imperfections in the seat or diaphragm, or if dust particles are introduced between the valve elements. a
Another object of my invention is to provide a unitary industrial respirator face piece including a pleated nose piece constructed in a manner so as to provide a comfortable, cushioned fit, particularly around the nose of the wearer.
Other objects and advantages of my invention will become more apparent from a study of the following description taken with the accompanying drawings wherein:
FIG. 1 is a front elevational view. of an industrial respirator embodying the principles of my invention.
FIG. 2 is a vertical cross-sectional view taken along line II-Il of FIG. 1. w
FIG. 3 is a rear view, with parts of the filter cups shown broken away, of the respirator face piece shown in FIGS. 1 and 2 and as viewed from the right-hand'side of FIG. 2.
FIG. 4 is an enlarged, elevational view of the exhalation valve seat shown in FIG. 2.
FIG. 5 is a crosssectional view taken along line VV of FIG. 4.
FIG. 6 is an enlarged elevational view of the exhalation valve shown in FIG. 2.
FIG. 7 is an enlarged view of the inhalation valve showing the mode of suspension, and
FIG. 8 is a vertical cross-sectional view taken along line VIlI-VIII of FIG. 7.
Referring more particularly to FIGS. 1 and 2 of the drawings, numeral 1 denotes a face piece of rubber or other suitable flexible material and which is of generally pear shaped contour, having an inwardly turned marginal lip or edge portion 1b along the mouth portion of the face piece 1. Portion 1b is of reduced thickness and is adapted to provide a cushioned contact about the nose, cheeks and chin of the wearer and to provide an air-tight or dusttight seal. The marginal edge portion lb is disposed in substantially a single flat plane and has an integral lower extension 10 which bridges the lower portion of the marginal edge portion 11b to form a chin rest, as shown more clearly in FIG. 3.
An important feature of the present invention resides in the construction and particularly the mounting of the inhalation valves 6 and 7. Such valves are suspended from rubber retaining studs 4 and 5, shaped somewhat like rivets, and integrally molded in the face piece 1. As will be noted in FIG. 8, the shanks of retaining studs 4 are disposed at right angles to the portion of the face piece 1 on which they are integrally molded. Thin rubber diaphragms or valves 6 and 7 are provided with a pair of holes along the top edges thereof corresponding to the positions of the studs 4 and 5, and of diameter substantially the same as that of the shanks of studs 4 and 5, whereby upon stretching of the top portion of diaphragms 6 and 7 they may be pushed in to clear the heads of the studs whereby the diaphragms may be attached to the shank portions of the studs 4 and 5 and held in place by the heads.
Face piece 1 is provided with a pair of integrally molded inhalation valve beads or seats, such as 111 and as shown more clearly in FIG. 8, which seats are in vertical planes which are disposed at a slight angle with the plane of the adjoining upper portion which carries studs .4 and 5. As valve 6 unseats from bead 1d, air may be inhaled through circular hole 1e formed on the left front side of the face piece communicating with a filtered air space inside cup 2a. A similar inhalation valve port is provided in the right front portion of the face piece :in communication with filter cup 3. Either filter pad discs or chemical cartridges may be used, interchangeably in cups 2a and 3a to filter dust or obnoxious fumes. By providing a pair of retaining studs supporting spaced portions of the top part of each inhalation valve diaphragm there will be no tendency for the diaphragm to rotate. Of course a single instead of a double stud may accomplish the same purpose by making an enlarged shank of square crosssection (not shown) if desired. It will be noted that there is no need for other means for supporting the diaphragms 6 and 7 than the retaining studs and molded seats, such as 1d.
An important feature of suspending diaphragms 6 and 7 from the top only without further support along the marginal portions is that gravity will assist in keeping the disphragms in their normal downward and seated positions as shown in FIG. 8. Furthermore, since air is exhaled from the nose in a downward direction such air will be in the proper direction to apply the necessary pressure to assure seating of the diaphragms d and 7 against their seats. Furthermore, since there are no metallic seat elements, there will be no objectionable noise producing vibrations as a consequence of opening and closing of the valves.
Another provision to facilitate breathing of the wearer and yet assure a perfect seal resides in the particular construction of the exhalation valve, the parts of which are shown more clearly in FIGS. 2, 4, 5 and 6. The exhalation valve or outlet valve seat 8 is preferably made of hard plastic material such as nylon, and is provided with a rim of channel shaped cross-section which provides a. well 8a forming a seat for the marginal portion of the face piece surrounding the exhalation port, as shown more clearly in FIG. 2. Valve seat 8 is inserted by forcing it in so as to stretch the face piece portion which surrounds the exhalation valve opening. The outlet valve seat is preferably provided with a plurality of integral sealing ribs or break edges 8b, 8c, and 8d which are disposed along an arc of a circle, for example, one having a radius of about 1% inches. A dished outlet diaphragm 9 is provided having a thickness of about .02 to .03 inch, which is adapted to become seated against each of the rim portions 8!), 8c and 8d. Diaphragm 9 may be a flat disc but is preferably molded in an arcuate shape so as to have an arcuate cross-section, as shown, but preferably of greater radius of curvature, such as, for example, 3% inch radius so that the diaphragm rim portion will be deformed from its normal position to assure constant seating engagement with the break edges 8b, 8c and 8d. Valve 9 has integral stem portions 9a and 9b which extend through the central hole 8 of the valve seat 8 until the enlarged stop portion 9c becomes seated on collar portion 8g so as to firmly hold diaphragm 9 in the seated position. Only three thin spokes 8e are provided in the valve seat to assure a large area for passage of exhaled air.
It will be noted that should valve 6 have an imperfection, such as a projection which engages one of the seating edges 8b, 80 or 8d and thus provide a leakage path or air, the other two edges will nevertheless prevent air flow since, in effect, there are three concentric valve seals. The grooves between the rim portions permit escape of excessive moisture from the sealing surfaces.
If desired, a marginal head (not shown) may be integrally formed on the top peripheral portion of valve diaphragm 9. The exhalation valve construction is such as to greatly facilitate breaking of the seal upon exhalation of wearer, as well as to allow quick and positive sealing engagement with the respective concentric seats upon inhalation of the wearer, thereby greatly reducing breathing resistance.
As shown more clearly in FIGS. 1 and 2, a nose pleated portion 1a is provided in the upper or nose surrounding of the face piece 1. The pleated portion 1a is of reduced thickness, such as of the order of .03 inch thick and is preferably in the form of a pair of steps in which the riser portions are about inch high and the tread portions, inch wide. The tread portions are substantially horizontal and the riser portions are disposed at about 10 with respect to a vertical transverse plane. As the pleats are flexed in response to pressure of the marginal portion 1b against the nose, the upper part of marginal portion 1b will pivot forwardly about a horizontal axis defined by the extremities of the pleated portion 1a so as to provide a very flexible and very comfortable fit around the nose of the wearer.
An outlet valve guard 10 is provided which is substantially cup shaped and having a radially inwardly turned marginal edge portion 1011 which is adapted to be seated in an annular groove formed along the perimeter of the exhalation port shown in the lower left end portion of FIG. 2. Thus guard 10 may be seated by forcing it into seating engagement with the groove in the face piece.
Thus it will be seen that I have provided a highly eflicient industrial respirator having relatively simple and inexpensive parts which may be easily and quickly assembled and detached, and which parts are of such construction as to greatly reduce breathing resistance and thus I of flexible material of substantially pear shaped outline,
avoid fatigue of the wearer; furthermore, I have provided a novel inhalation valve suspension which assures easy flexing of the valve diaphragm to the open position and which is so arranged that the valve will close forcibly with the aid of exhaled air directed in the proper direction; furthermore I have provided an efficient exhalation valve construction which will assure positive sealing engagement with at least one or more of a plurality of concentric sealing rings irrespective of imperfections in the valve diaphragm or seats.
While I have illustrated and described a single specific embodiment of my invention, it will be understood. that this is by way of illustration only, and that various changes and modifications may be made within the contemplation of my invention and within the scope of the following claims.
1'. In an industrial respirator comprising a face piece a pair of filter boxes secured to the exterior of the enlarged sides thereof, a pair of inhalation valves mounted on the interior surface of said face piece in communication with said filter boxes, each of said inhalation valves comprising a thin, flexible valve diaphragm and a pair,
of suspending stud elements located in close, side by side relationship above the diaphragm and integrally secured to the inner surface of the face piece, there being no other valve fastening elements, whereby substantial flexing of said diaphragm and minimum breathing resistance are provided;
2. A respirator as recited in claim 1 wherein said face piece has inhalation valve ports which have beads integrally molded on said face piece along the marginal portions thereof which form seats for the inhalation valve diaphragms.
3. A respirator as recited in claim 1 wherein said inhalation valve stud elements are in the form of rubber rivets having shank portions, a pair of holes substantially the same diameter as said shank portions formed in the top of each inhalation valve diaphragm through which the shanks of said stud elements extend.
4. A respirator as recited in claim 1 together with an exhalation valve in said face piece comprising a detachable, wheel-like valve seat having a rim portion of substantially U-shaped cross-section attached to the peripheral portion of an exhalation valve opening in the lower front portion of the face piece.
5. A respirator as recited in claim 4 together with a groove integrally formed in said face piece and extending about the exhalation valve together with a valve guard of substantially cylindrical cup shape having an inner marginal edge portion which is adapted to project into said groove to form a slip-fit therewith.
References Cited in the file of this patent UNITED STATES PATENTS 922,262 Clemens May 18, 1909 1,310,119 Harper July 15, 1919 2,036,850 Bullard Apr. 7, 1936 2,378,613 Young et a1. June 19, 1945 2,738,788 Matheson et a1 Mar. 20, 1956 2,744,525 Whipple May 8, 1956 2,744,539 Jones May 8, 1956 2,745,133 McWethy May 15, 1956 2,818,861 Russell Ian. 7, 1958 2,858,828 Matheson Nov. 4, 1958
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