US3400713A - Apparatus for intermittently dispensing oxygen or other gas suitable for breathing - Google Patents

Description

J. E. FINAN 3,400,713

Sept. 10, 1968 APPARATUS FOR INTERMITTENTLY DISPENSING OXYGEN OR OTHER GAS SUITABLE FOR BREATHING 2 Sheets-Sheet 1 Filed Oct. 12, 1966 7 vi i) o'i ijigull 2 I I h 29 l I I 4 :l. '7. 2'5; f zzi fsll 251 25 1 4' 23} INVENTOR H i, E JAMEs E. FINAN 23 ATTORNEY J. E. FINAN 3,400,713 APPARATUS FOR INTERMITTENTLY DISPENSING OXYGEN OR OTHER Sept. 10, 1968 GAS SUITABLE FOR BREATHING Filed Oct. 12, 1966 2 Sheets-Sheet 2 M A mm W W57 5 a E MM A J7 Y B E 1 m F i v 3 2 a L dyi Mu fi fig ATTORNEY United States Patent 3,400,713 APPARATUS FOR INTERMITTENTLY DISPENS- INGOXYGEN OR OTHER GAS SUITABLE FOR BREATHING I I James E. Finan, 1193Hartlscrabble Road, 'Chappaqua, N.Y. 10514 Continuation-impart of application Ser. No. 479,128, Aug. 12, 1965. This application Oct. 12, 1966, Ser.

No. 586,278 I 7 Claims. (Cl. 128203) ABSTRACT OF THE DISCLOSURE In apparatus for supplying oxygen for breathing, including a source of oxygen, an egress member adapted to supply a person, conduit means leading from the source of oxygen to the egress member, and sensing means adapted to move in first and second directions upon expansion and contraction respectively of the girth of the torso of said person, the improvement in combination therewith for opening and closing the conduit means, for passage of oxygen from the source to the egress member intermittently and in response to each inhalation by the person, comprising valve means interposed in the conduit; a pairof cooperating parts including means defining a chamber member including a wall at on end thereof supported and guided for reciprocal sliding motion, and a piston slidably disposed within the chamber member means in substantially gas-tight peripheral contact with the inner surface thereof; one of the pair of parts being arranged to act as the driven one and actuate the movable portion of the valve means; the other of the pair of parts being arranged to act as the driving one and connected to the sensing means to move in the first and second directions therewith; and means biasing the driven one in a direction tending to move said valve means movable part to the closed position thereof. Desirably, a controlled leak means is provided into the variable chamber portion, so that the vacuum produced therein upon relative motion of the piston and chamber member means end wall away from one another is dependent upon the rate of movement as well as the direction and distance of movement.

Backgnound of the invention This application is a continuation-in-part of my copending application, Ser. No. 479,128, filed Aug. 12, 1965, entitled System for Intermittently Dispensing Oxygen or Other Gas Suitable for Breathing.

Various systems, devices, and techniques are known for supplying oxygen for breathing. When the term oxygen is employed herein, it will be understood that what is meant is oxygen, or mixtures of oxygen With other gases, such as nitrogen, helium, etc., suitable for breathing. In general substantially pure oxygen will be employed, and will be admixed and diluted with air at the users nostrils, as will appear herein-after. It is known to provide a portable oxygen dispensing apparatus for supplying oxygen, or to supplement the supply of oxygen for breathing purposes. Such systems and techniques heretofore have generally involved supplying oxygen continuously. For example, such systems and techniques heretofore have involved continuously supplying oxygen for breathing both during inhalation and exhalation.

Supplying oxygen for breathing purposes when the person is exhaling is wasteful since unless confined or channeled or captured by suitable means (which means would be cumbersome) the oxygen supplied for breathing during exhalation would, escape to the atmosphere. Despite this situation portable oxygen dispensing means known here- 3,400,713 Patented Sept. 10, 1968 tofore generally supply oxygen substantially continuously for'breathing. This has necessitated the waste'of at least half of the capacity of any oxygen source. Since oxygen is normally gaseous and has a low boiling point, strong and heavy containers must be employed to contain the oxygen. This has contributed substantially to theweight of the portable oxygen breathing apparatus, and to the efiort and discomfort of the person carrying the same. Also, obviously, such systems and techniques are wasteful of oxygen, which has a substantial economic value.

There are. many situations in which an individual may require administration of oxygen for breathing, or administration of oxygen for assistance in breathing. One fairly common situation involvesemphysematous individuals, wherein the individual must have a supply of oxygen to assist in breathing over considerable periods of time. Such individuals are not otherwise ill, and can be expected to move about, thus requiring a portable apparatus of the type described, wherein waste of oxygen is reduced consistent with reliability and steady performance. The demand, among patients requiring this kind of therapy, for a'portable and reliable apparatus thus makes the problems with continuous oxygen supply systems, such as wasted oxygen capacity, particularly important.

The invention applies, however, to anyone in need of oxygen therapy, e.g., heart patients, polio or lung cancer patients, asthmatics, and others, in addition to emphysematics.

It is an object of the present invention to provide a relatively lightweight, simple, portable system for dispensing oxygen intermittently and on demand.

Another object of the present invention is to provide a technique for supplying oxygen for breathing in a manner particularly useful for a person in oxygen therapy.

Yet another object of the present invention is to provide a portable oxygen supply apparatus adapted to be worn on the person providing a long useful life for a given amount of oxygen contained in the apparatus as compared with other known comparable portable apparatus which continuously dispense oxygen.

Still another object of the present invention is to provide a portable apparatus adapted to be Worn on the person for the supply of gaseous oxygen for breathing purposes wherein the face of the person wearing the same is free and exposed save for a nasal cannula or the like for the supply of the dispensed oxygen and wherein the freedom of movement of the person wearing the system, including the use of his nose or mouth, is substantially unrestricted.

Still another object of the present invention is to provide an oxygen supply apparatus adapted to be worn on the person for the supply of oxygen for breathing purposes via the nose or mouth and only when the person is inhaling, the mouth or nose not being necessarily sealed to the apparatus during use, so that the oxygen supplied by the apparatus can be supplementary to air breathed in parallel with the apparatus through the nose or mouth.

Still another object of the present invention is to provide an oxygen supply apparatus of the character described wherein intermittent supply of oxygen is actuated by the breathing movements of the wearer himself.

Still another object of the present invention is to provide an oxygen supply apparatus of the character described wherein only mechanical parts are employed thereby increasing reliability.

How these and other objects of this invention are achieved will become understood in the light of the following disclosure made with reference to the accompanying drawings, wherein:

FIG. 1 shows the first embodiment of the invention, but is illustrative of the general disposition and arrangement of either embodiment of the apparatus in accordance" with the invention, when worn on the person;

FIG. 2 is a top view of the first embodiment of an actuating element employed in the apparatus according to the invention;

FIG. 3 is a front elevation view of the element shown in FIG. 2;

FIG. 4 is a section view of the element shown in FIG. 2 taken along plane 4-4 therein and showing the internal parts occupying the relationship corresponding to exhalation by the wearer;

FIG. 5 is a view corresponding to the view shown in FIG. 4 and showing the internal parts thereof occupying the relationship corresponding to inhalation by the wearer;

FIG. 6 is a section view of the apparatus shown in FIG. 5 and taken along plane 66 therein;

FIG. 7 is a section view of a portion of the apparatus shown in FIG. 4 taken along plane 77 therein;

FIG. 8 is a section view of a portion of the apparatus shown in FIG. 4 taken along plane 8-8 therein;

FIG. 9 is a top view of a second embodiment of an actuating element employed in the apparatus according to the invention;

FIG. 10 is a front elevation view of the element shown in FIG. 9;

FIG. 11 is a section view of the element shown in FIG. 9 taken along plane 1111 therein and showing the internal parts occupying the relationship corresponding to inhalation by the wearer; and

FIG. 12 is a section view of the apparatus shown in FIG. 11 taken along plane 1212 therein.

In accordance with the invention there is provided a mechanical oxygen valving arrangement whereby expansion movements of the torso of the wearer opens valve elements allowing oxygen to pass to the wearer, while contraction movement of the torso of the wearer closes the valve elements stopping the flow of oxygen to the wearer. The expansion movements of course correspond to inhalation, and the contraction movements correspond to exhalation.

It is a feature of the invention that the opening and closing of the valve elements, while controlled in the manner justdescribed, are not dependent upon regularity in the inhalation-exhalation cycle, but rather are eflected at any time they are required. That is to say, a deep inhalation can interrupt a shallow exhalation, or any other combination in degree and period of inhalation and exhalation can be praciced, and in each instance the valving elements will respond to the wearers diaphragmatic movement regardless of what state and what portion of an opening and closing cycle those valving elements are then in. The equipment is enslaved to the user, which is a departure from all so-called intermittent demand respiratory-aid systems previously known, in which the user is imprisoned to the system by a closed connection between hisbreathing orifices and the apparatus, with the intermittent oxygen fiow being turned on and ofl by his alternately sucking and blowing into the equipment.

The combination of these features results in an apparatus which is very flexibly tailored to the breathing needs of any wearer, and particularly of a wearer having emphysema, cardiopulmonary condition, or any other respiratory ailment involving oxygen insufiiciency. Additionally there is the longer life oxygen supply (due to diminished waste), and the decreased weight and bulk, which altogether give to the present apparatus important advantages over anything the art has heretofore provided.

Referring now to the figures, and initially to the general FIG. 1 together with FIGS. 2-8 showing the first embodiment of the invention, there is illustrated a container 20 suspended from one shoulder of a person wearing the same by means of shoulder strap 21. Container 20 is provided with an oxygen source, such as a small oxygen tank, together with associated equipment such as a shutotf valve, all not shown but suitably disposed within con- 4 tainer 20. Conduit 22a, such as a flexible plastic tubing, leads from container 20 to an actuating element indicated generally at 23 wherein are included valving elements, and a conduit 22b leads from actuating element 23 to nasal cannula 24 which is held in place on the face of the wearer by means of adjustable strap 25. The actuating element 23 is worn at the midriff of the person, i.e. at about the level of his diaphragm, and is held in place by means of a belt 29 which encircles the body of the person wearing same. It will be appreciated that belt 29 tends to be more tight upon inhalation, and less tight upon exhalation. In a manner presently to be described with reference to the internal details of actuating element 23, the increased tension in belt 29 corresponding to inhalation causes the valving elements of actuating element 23 to pass oxygen from conduit 22a to conduit 22b, and the decrease in tension in belt 29 corresponding to exhalation causes the valving elements of actuating element 23 to close off the oxygen path from conduit 22a to conduit 22b.

In FIG. 4 the relationship of the parts may be seen when the valving elements are closed, corresponding to exhalation by the wearer. In FIG. 5 the relationship of the same parts may be seen when the valving elements are opened, corresponding to inhalation by the wearer. Referring to both of these figures, the first embodiment of actuating element 23 comprises a body portion 23a formed as a laminated structure having a centrally located portion 23b (FIG. 6) sandwiched between front and rear plates 23c, 23d. Central portion 23b has an appreciable thickness compared to plates 23c, 23d, and as may be seen in section in FIGS. 4 and 5 is provided with a plurality of internal passageways and chambers, most of which extend completely between the opposed major faces of central portion 23b. The plates 23c, 23d thus serve to complete the walls of these passageways and chambers at the major surfaces of central portion 23b. Plates 23b, 230 are secured to central portion 23b by a plurality of fastening members 23c, e.g. machine screws. Rear'plate 23d extends beyond the lateral extreme of central portion 23b at portion 23d, and is curved thereat to conform to the body of the wearer, as may be seen particularly in FIG. 2.

Specifically, body portion 23a is provided with a pair of internal passageways 231, 23g which meet and connect at a valve seat portion 23h. Valve seat portion 23h is, in the embodiment shown in FIGS. 4 and 5, formed as a countersunk cylinder whose axis lies along the major axis of central portion 23b. A valve seat member 231' is disposed within seat portion 23h, and is shaped to accommodate a spherical valve member in seating engagement therewith. Each of passageways 231, 23g terminate at a first end 231' of central portion 23b at threaded orifices 23k and 23m respectively. Threadedly engaged with in orifices 23k, 23m are conduit fittings 26a, 26b, each of which is provided with a barbed exterior outline for secure engagement with the end interiors of conduits 22a, 22b, respectively. It will be appreciated that oxygen gas is supplied to fitting 26a from conduit 22a, so that whenever there is free communication between passageway 23f and passageway 23g this oxygen will flow through passageways 23 23g out fitting 26b and to the cannula 24 via conduit 22b.

Nearer end 2311 of cenral portion 23b, i.e. the end opposite end 23 is situated an internal chamber 23p, which is rectangular in cross-section, as may be seen in FIG. 6. A countersunk bore 23q connects internal chamber 23 with passageway 23 and is coaxial with seat portion 23h and valve seat member 23i. The upper and lower extremes of the half of central portion 23b adjacent end 2311 are stepped downwardly and upwardly respectively, so that an upper groove 23! and a lower groove 23s (FIG. 6) are formed in cooperation with plates 23c, 23d. A pair of threaded bores 23! extend from groove 23:- to internal chamber 23p, and a second pair of threaded bores 23a extend upwardly from groove 23s to internal chamber 23p.

Located within chamber 23p, in close fitting but slidab'le relation therein is a rectangular cross-section means defining a chamber member 23v, having a closed end situated within internal chamber 23p at the end thereof adjacent countersunk bore 23q. For convenience, the means defining a chamber member 23v, which can either be rectangular (FIG. 6) or cylindrical (FIG.12) in crosssection, shall be termed cannister 23v hereinafter. An adjustable air orifice 23x is carried at the closed end of cannister 23v, and in FIG. 8 may be seen as including a passage 23y opening outside of cannister 23v, a passage 23z opening into the interior of cannister 23v, and a threadedly adjustable needle valve 2341a adapted to seat at the intersection of passages 23y, 232 to completely close communication therebetween or to open communication therebetween to varying degrees. As will be understood bythose skilled in the art, needle valve 23cm is employed to provide an adjustable access for gas flow through passages 23y, 232 at a low range of rates, which would be classified by the art as leak rates.

Adjacent to and concentric with adjustable air orifice 23x is located a valve ball holder 23bb comprising a rod 23cc slidably extending through countersunk bore 23q, secured to a ball 23dd on the left side of bore 23: and secured at the right side of bore 23g by a pair of branches 23e'e to the closed end of cannister 23v. A compression spring 2317 is mounted concentrically on rod 23cc at the portion'thereof between the ball 23dd and the larger diameter portion of countersunk bore 23g. It will now be appreciated that when cannister 23v is slidably moved within internal chamber 23p, ball 23dd will seat upon valve seat member 23i at one extreme position of cannister 23v, i.e. at the leftmost position shown in FIG. 4,

and will be withdrawn away from seating engagement with valve seat member 23i when cannister 23v is slidably moved in the opposite direction as is shown in FIG. 5. The spring 2317, while it opposes unseating of ball 23ad, is not a major factor therein, being assisted by other, more powerful springs, as will appear hereinafter. The spring 23f is rather included as a fine adjustment on the precise seating of ball 23dd on seat 23f in the closed position. Movement of cannister 23v thus controls the closing and opening of the connection between conduits 22a, 2217 by the corresponding movement of ball 23dd respectively into seating engagement as illustrated in FIG. 4 and out of seating engagement as illustrated inFIG. 5.

At the end of cannister 23v closer to end 2311 of central portion 23b is located a peripheral flange 23gg, and a compression spring 23hh is captured between flange 23gg and the adjacent inner end of internal chamber 23p. Compression spring 23hh urges cannister 23v toward the left as viewed in FIGS. 4 and 5, thus acting in parallel with spring 2300, so that cannister 23v is normally urged to the left until ball 23dd is seated on valve seat member 231, so that valve 23dd 23i is normally closed. The slidability of cannister 23v within internal chamber 23p, i.e. the friction restraint force, is adjusted and standardized by a plurality of nylon slide bearing members 23ii located within bores 231, 2311, and urged against the upper and lower exterior of cannister 23v (FIG. 6) by a plurality 'of spring loaded screw assemblies 23jj which hear thereupon, and are adjustable in bearing force. It will be appreciated that by initial adjustment of the bearing force exercised at bearing members 23ii the amount of sliding friction restraining force on cannister 23v can be ad 'justed, so that'the effect of that parameter on the functioning of the device, presently to be described, can be adjusted to any desired and thenceforth fixed value.

Slidably enclosed within internal chamber 23p is a close fitting rectangular piston 23kk (FIGS. 4 and 5) formed ,of a smooth, self-lubricating material, such as Teflon; nylon, or a graphite 'filled body, so that sliding within internal chamber 23p may be accomplished with virtually no leakage of air past the piston along its peripheral sliding contact surface with internal chamber 23p. As may be seen in FIG. 7, piston 23kk-includes a piston rod 23mm which is terminated by a ball member 23nn. A valve chamber 23pp is formed centrally in piston 23kk, and includes a rigidly mounted ring-disc 23qq. Spaced from ring-disc 23qq is a valve seat portion 23rr of chamber 23pp,-.which seat 23rr is adapted to provide an air tight seal with ball 23nn when piston rod 23mm is moved to the right, as viewed in FIGS. 5 and 7. A helical compression spring 23ss normally forces ball 23m and ring-disc 23qq apart to opposite ends of chamber 23pp, thus seating ball 23mm on seat 23rr. Ball 231111 does not form a gas-tight-se'al with ring-disc 23qq, but rather is simply abutted thereagainst when ball 23nn is moved to the left, as viewed in FIG. 7, against resistance of spring 23ss, so that air passage is provided past ball 23nn and ring-disc 23qq when the former is in contact with the latter. It will be appreciated that by these means a check .valve arrangement is provided within piston 23kk so that when piston rod 23mm is moved to the right, air cannot pass from one face of piston 23kk to the other, but when piston rod 23mm is moved to the left, air is free to so pass.

Belt 29 is anchored to a rod 23!! secured to a U-shaped slider 23uu slidably captured within a slot 23W in curved portion 23d of rear plate 23d. Piston rod 23mm is connected to a rod 23ww secured to slider 231m, and a pair of tension springs 23xx extend along upper and lower grooves 23r and 23s of actuating element 23 to connect rod 23ww of slider 23uu to machine screws 23e anchored in body portion 23a. The opposite end of belt 29 is secured to a generally triangular buckle 23yy (FIGS. 4 and 5) which is removably captured by a J-shaped bracket 23zz (FIG. 2) secured to the end of actuating element 23 adjacent conduit fittings 26. The springs 23xx and the portion of body portion 23a left of screws 23e thus form a part of the total girth of belt 29. The springs 23xx accommodate the expansion and contraction of that girth due to the wearers inhalation and exhalation, and act to bias belt 29 toward contraction of its girth.

In operation, the actuating element 23 will be held securely by one end of belt 29 attache-d thereto at buckle 23yy, and movement of the diaphragm will be reflected at the opposite end of belt 29 at slider 231m. Thus expansion and contraction of the wearers diaphragm will cause belt 29 to move slider 231m to the right and left respectively, relative to body portion 23a of actuating element 23, respectively against and with the contraction force of tension springs 23xx. The arrangement of parts shown in FIG. 4 indicates a time during the wearers breathing cycle when he is in the process of exhaling or has just completed an exhalation, so that his girth at belt 29 has decreased, thereby allowing the circumference of belt 29 to decrease under the urging of tension springs 2310:, together with the urgings of compression springs 231th and 2315. When belt 29 is so moved,,piston rod 23mm is moved to the left so that ball 23nn in piston 23kk leaves its seat 23i-r and contacts ring-disc 23qq. This allows gas to pass from one side of piston 23kk to the other, so that the piston moves freely to the left dur ing exhalation allowing trapped gas to pass to the right side thereof. The springs 23xx are thereby enabled to contract the girth of belt 29, moving piston 23kk to the left, without resistance force from gas trapped to the left thereof.

When piston 23kk moves to the left, indicating contraction of belt 29 and accordingly commencement of exhalation by the wearer, piston valve 23nn, 23rr will open, so that the cannister 23v will have no partial vacuum force holding it rightward, and under the urging of springs 23kk, 2317 it will move leftward until ball 23dd seats on seat 231. As will appear hereinafter, whether cannister 23v moves to the left in response to actual leftward movement of piston 23kk, or whether it precedes such by virtue of the leak of gas at needle valve orifice 23x, depends upon the peculiarities of the wearers breathing cycle in general, and the instant cycle in particular. This important feature will be discussed'in detail hereinbelow. Here, it is necessary only to appreciate that when the partial vacuum at the closed end of cannister 23v, to the left of piston 23kk, is broken by 'piston valve 23", 23rr or leaked away sufiiciently by cannister needle valve orifice 23x, the valve 23dd, 23i, controlling oxygen'flow, will close. It will be appreciated that whenball 23dd seats upon seating element 23i oxygen can no longer flow from conduit 22a to conduit 22b, thereby preventing the supply and waste of oxygen during the portion of the wearers breathing cycle when he is not inhaling, with the attendant benefits and advantages already set forth.

When inhalation is next commenced in the breathing cycle, belt 29 will begin to be increased in girth by the expansion of the wearers torso at belt 29, and accordingly slider 23uu will begin to move toward the right, as viewed in FIG. 5. Depending upon the adjustment of belt 29 and the adjustment of the various other parts, at a certain point in the inhalation portion of the breathing cycle, preferably at or near the commencement thereof, ball 23dd will be moved away from seating relation with seat member 23i, as illustrated in FIG. 5, to allow oxygen gas to pass from conduit 22a to conduit 22!) and thereby to cannula 24. This occurs because valve 23ml, 23rr or piston 23kk is closed by a rightward movement of piston rod 23mm, thus creating a partial vacuum within the closed end of cannister 23v to the left of piston 23kk. Cannister 23v, under the vacuum created force, follows piston 23kk to the right, but only as long as piston 23kk moves to the right. Moreover, the constant gas leak into cannister 23v at needle valve orifice 23x will return cannister 23v to the left after piston 23kk stops moving rightward.

The internal parts of actuating element 23 cooperate to provide the closing of valve 23a'd, 23i during exhalation and the opening thereof during inhalation, for the purposes stated. When an inhalation occurs belt 29 is increased in girth so that slider 231m moves toward the right thus drawing piston 23kk to the right, seating piston ball 231m against seat 23rr so that a partial vacuum is created in the closed end of cannister 231 If the expansion of belt 29 indicates an inhalation, the rate and depth thereof will be such that the vacuum created within cannister 23v will build up despite the leak at needle valve orifice 23x. The cannister 23v will therefore follow piston 23kk to the right by virtue of the vacuum-created force, and the valve 23dd, 23i will open, admitting oxygen to cannula 24.

Thus if the wearer has an inhalation, whether shallow girth of the wearer at belt 29 continues to expand. In general, during inhalations, it will remain open for a slight period after the diaphragm of the wearer has stopped expanding, because there will be a certain amount of time during which the cannister 23v returns to the left as the partial vacuum therein continues to be dissipated. But the essential point is that when the diaphragm has stopped expanding the valve 23dd, 231' will, an adjustable but definite time thereafter, close. This prevents wasting of oxygen due to the fact that most people, particularly when at rest, have a significant period between the end of an inhalation and the beginning of an exhalation. The apparatus according to the invention does not wait until the exhalation has begun to'close the valve 23dd, 23i, thus saving still more oxygen. Shallow inhalations open the valve 23dd, 23: for short periods of time, while deep inhalations open the valve 23dd, 23i for long periods of time, and in all cases, the period of time which the valve is open is exactly correlated to the extent of the inhalertion, specifically excluding the dwell period at the ,end thereof.

Cannister 23v is restrained by springs, and particularly by spring 23hh. A certain minimum force is required to move cannister 23v to the right at all against this restraining force. Most body movements other than inhalations will be shallow and of short duration as farv as their effect on belt 29 is concerned, and any resultant move,- ments of piston 23kk to the right will not generate enough partial vacuum in the closed end of cannister 23v to unseat valve 23dd, 231' in the first instance, because of the restraining bias of spring 23%. The total bias of course includes springs 23xx, and these springs can be adjusted initially by the wearer by adjusting the position of buckles on belt 29, to lengthen or shorten the effective belt girth.

The main point of the invention is the decrease in oxygen consumption by at least half, resultant from valving off the oxygen during exhalation. Of distinctly subsidiary importance, is the feature of valving off at the end of inhalation rather than the beginning of exhalation (whenever there is a dwell), and the discrimination between torso movements other than inhalations, from inhalation movements. The latter discriminations occur because of the spring bias, just described, the leak rate into cannister 23v which will prevent very slow expansions of the wearers torso (e.g. frequent natural shiftings of posture) from unseating the valve 23dd, 23i, and the fact that any reversal of direction of piston 23kk, even momentarily, will cause full return of cannister 23v. Although the oxygen saved by these features is very subsidiary to the gross savings effected by the valving off of oxygen during exhalation itself, such subsidiary savings do constitute additional advantages of the apparatus.

Referring now to FIGS. 9-l2 there is shown a second embodiment of the invention. The principles employed in the second embodiment are of course the same as those employed in the first embodiment and like reference characters in the two embodiments denote like parts therein. In the second embodiment the adjusting element 23 is not constructed as a laminate wherein two plates sandwich an intermediate body portion therebetween as in the first embodiment. Rather as may be seen in FIGS. 9 and 12, adjusting element 23 includes a thicker body portion 23a to which is secured the single plate 23d at the rear thereof facing the wearer. Plate 23d has at one end thereof the hook 23zz for connecting one end of belt 29, and at the other end thereof has the curved portion 23d having the slot 23w accommodating the slider 23uu attached to the other end of belt 29, all as in the first embodiment. In this second embodiment the upper and lower grooves 23r, 2 3s appear at the rear of the-body portion 23a, and are completed by the adjacent portion of rear plate 23d. The springs 23xx are accommodated in these grooves in the same manner as previously described. The slider 231m is connected to a piston rod 23mm, which in this embodiment is curved at the portion connected to slider 23uu. This is done because a circular cylindrical piston 23kk' is employed having a greater front to rear dimension than the rectangular piston 23k]; of the first embodiment. This places piston rod 23mm at a greater distance forward of rear plate 23d thus necessitating the bend in the'endpf the rod secured to slider 23ml. Of course pistons of other cross-sectional configurations may alternatively be eniployed, I

A flanged fitting 30 is threadedly engaged within a threaded end portion of an internal chamber 23p. Flanged fitting 30 serves, to act as a housing for compression spring 231th and also acts as a limit stop for the rightward motion of a cannister 23v. The internal chamber 23p and the cannister 231; are of coursecylindrically formed to correctly cooperate with each other and with the cylindrical piston 23kk'. The relationship of p i ston 23kk' to cannister 23v is otherwise the same as'has already been described, except that there is no positive connection between cannister 23v and the valvecontrolling theflow ofoxygen from conduit 22a to conduit'22b. Instead of seat portion'23h' being concavely formed to accept a ball in seating'relatio'nship as inthe first embodiment, it is convexly formed to cooperate with a planar movable sealing surface 23dd. While in the first embodiment the valve parts 23dd, 231' were normally held together by spring23ff; in the second embodiment the valve parts 23dd",=23i"are normally -heldapart'by virtue of a compression spring 23H. 'The valve 23dd','-2 3iof the second embodiment is; however, still normally closed just as in the first embodiment, because cannist'er 23v is normally urged leftward just as is cannister 23v, by their respective springs 23hh, 23hh. The effect from the-standpoint of the total device then-is only to sever thepositive connection between cannister 23v and valve member23dd'. Y I

'When cannister'23v' is moved to the right," as viewed in FIG; 11, thus indicating an inhalation by -thewearer, the adjustable air orifice portion 23x thereof is moved away from the member 23dd, allowing the spring 23f to open the valve 23dd', 23i-thus allowing oxygen to pass from conduit 22a to conduit 22b, and hence to cannula 24 (FIGS. 1 and 5). When cannister 23v' returns to the left, either because of the return of piston rod 23mm to the left or because of dissipation of the partial vacuum within the closed end of cannister 23v by adjustable air orifice portion 23x, it will once again contact and move member 23dd under the urging of spring 23hh back toward the left againstspring 23ff' into sealing contact with seating surface 23i'.

It will thus be appreciated that in the second embodiment there is no positive connection between the valving members 23dd', 215i and the cannister 23v which together with the convenience of fitting 30, allows easier disassembly of the parts inside chamber 23p for cleaning or adjusting. Moreover, the greater thickness of body portion 23a allows use of a cylindrical and greater effective area piston 23kk, providing greater vacuum force on cannister 23v per unit movement of piston '23kk' to the right. In all other respects, as has already been mentioned, the two embodiments operate in precisely the same manner, and upon the same medical and mechanical principles.

While the invention has been described with reference to two specific embodiments, this has been for purposes of illustration only, and in no way has been intended to limit the invention. Rather, as will be apparent to those skilled in the art, many modifications in form and arrangement of parts can be practiced Within the scope of the principles of the invention as taught herein.

What is claimed is:

1. In apparatus for supplying oxygen for breathing, including a source of oxygen, an egress member adapted to supply a person, conduit means leading from said source of oxygen to said egress member, and sensing means including a first portion adapted to girdle a persons torso and a second portion adapted to move in first and second directions upon expansion and contraction respectively of the girth of the torso of said person, the improvement in combination therewith for opening and closing said conduit means for passage of oxygen from said source to said egress member intermittently and in response to each inhalation by the person, comprising:

(a) valve means interposed in said conduit, having a movable portion movable between open and closed positions of said conduit; (b) a body portion supported by said sensing means;

(0) means defining a chamber member having a con stant cross-section interior space along an axis thereof, including a wall at one end of said axis, said chamber member means being supported and guided by said body portion for reciprocal sliding motion with said sensing means second portion parallel to said axis;

10 (d) a piston slidably disposed within .said chamber member means in'substantially" gas-tight peripheral contact with the'inner surface thereof, one ,face of said piston constituting a movable wall cooperating -with the interior portion of saidcha'rnbermember meansadjacent said wall at said one-end to define therebetween a variable chamber portion;

1 (e) means 'connecting'one' of the pair comprising said chamber membermeans and-said piston to said sensing means thereby constituting that one as-the-driving means of the pair and the other one as the driven means of the pair, so that the driving means one'moves with said sensing means in said first and second directions; to tend to increase and decrease respectively the volume of said "variable chamber portion by moving said end wall and said pistoh respectively away from and toward one another;

(f) means effecting an actuating link between the driven means one of said pair and said valve means movable portion for movement of the valve means movable portion between said open'and closed positions of said conduit; and

(g) means referenced to said body portion and biasing the driven one of said pair in a direction-tending to eifect movement of said valve means movable portion to the closed position.

'2. Apparatus according to claim 1 wherein is included means defining a controlled leak into said variable chamber portion of said chamber member means.

3. In apparatus for supplying oxygen for breathing, including a source of oxygen, an egress member adapted to supply a person, conduit means leading from said source of oxygen to said egress member, and sensing means including a first portion adapted to' girdle a persons torso and a second portion adapted to move in first and second directions upon expansion and contraction respectively of the girth of the torso of said person, the improvement in combination therewith for opening and closing said conduit means for passage of oxygen from said source to said egress member intermittently and in response to each inhalation by the person, comprising:

(a) valve means interposed in said conduit, having a movable portion movable between open and closed positions of said conduit;

(b) a body portion supported by said sensing means;

(c) means defining a chamber member having a constant cross-section interior space along an axis thereof, including a wall at one end of said axis, said chamber member means being supported and guided by said body portion for reciprocal sliding motion with said sensing means second portion parallel to said axis;

((1) a piston slida'bly disposed within said chamber member means in substantially gas-tight peripheral contact with the inner surface thereof, one face of said piston constituting a movable wall cooperating with the interior portion of said chamber member means adjacent said wall at said one end to define therebetween a variable chamber portion;

(e) means effecting an actuating link between said chamber member means and said valve means movable portion for movement of the valve means movable portion between said open and closed positions of said conduit;

(f) means connecting said piston to said sensing means a for movement thereof with said sensing means in said first and second directions, to move said piston respectively away from and toward said chamber member means end wall; and

(g) means referenced to said body portion and biasing said chamber member means in a direction tending to move said valve. means movable portion to the closed position.

4. Apparatus according to claim 3 wherein is included 111' means defining acontrolled leak into said varia'ble chamberportion of said chamber member means. 5. Apparatus according to claim 4 wherein said controlled leak means comprises an orifice connecting said variable chamber portion end wall to the ambient atmosphere, and a needle valve adjustable with respect to said orifice. Y

' 6. In apparatus for supplying oxygen for breathing, including a source of oxygen, an egress member adapted to supply a person, conduit means leading from said source of oxygen to, said egress member, and sensing means adaptedcto girdle said persons torso and having a first end adapted to move in first and second directions relative to a second end upon expansion and contraction respectively of the girth of the torso of said person, the improvementin combination therewith for opening and closing said conduit. means for passage of oxygen from said source to said egress memberintermittently and in response to each inhalation by the person, comprising:

1 (a), valve means interposed in said conduit, having a movable portion movable'bet-ween'open and closed positions of said conduit, and a fixed portion connected to said second end of said sensing means;

(1b) a body portion supported by said sensing means; (c) means defining a chamber member having a constant cross-section interior space along an axis thereof, including a wall at one end of said axis, said chamber member means being supported and guided by said body portion for reciprocal sliding motion parallel to said axis in response to relative motion between said sensing means first and second ends; (d) a piston slidably disposed within said chamber member means in substantially gas-tight peripheral contact with the inner surface thereof, one face of said piston constituting a'movable wall cooperating move sa1d plston respectively away from and toward said chamber member means end wall; and (g) means referenced to said body portion and biasing said chamber member means in a direction tend- 15 ingto move said valve means movable portion to the closed position.

7. Apparatus according to claim 6 wherein is included means biasing said first and second ends of said sensing means toward one another thereby tending to decrease 2 the girdling circumference of-said sensing means.

References Cited UNITED STATES PATENTS 25 2,774,348 12/1956 Emerson 12s 30 2,912,979 11/1959 Lieber 128-203 3,331,368 7/1967 Bird et a1. 128l45.8

FOREIGN PATENTS 30 1,048,391 1/1959 Germany. 1,124,631 3/1962 Germany.

RICHARD A. GAUDET, Primary Examiner.

K. L. HOWELL, Assistant Examiner.

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