US3426745A - Bag means for collecting breathing and rebreathing air samples - Google Patents

Description

A. F. FARR 3,426,745

BAG MEANS FOR COLLECTING BREATHING AND REBREATHING AIR SAMPLES Feb. 11, 1969 Filed March 27, 1967 v /NVNTO/ ANQREW E FARR A FOP/V5) United States Patent 8 Claims ABSTRACT OF THE DISCLOSURE A pliable gas-impervious bag having a two-way nonrestrictive valve, including a mouthpiece, by means of which samples of air from free breathing and rebreathing of a person may be collected for analysis. The device is light-weight for portability, and of low cost to permit discarding after one use.

Cross-references to related applications This application is a continuation-impart of my pending application for patent, Ser. No. 295,058, filed July 15, 1963 now abandoned, in which claims to a specific valve member per se were divided out.

Background 0 the invention The invention relates to apparatus for the collection of breath samples for clinical examination.

The apparatus for the collection of breath samples which has heretofore been available, has been found to be inadequate for diagnostic uses in present-day medical practice because of their overall weight and cost, precluding single use and discarding, and because the valving units are restrictive during change, producing back pressure on the patients breathing. Further, the bags have not been made from gas-impermeable materials, nor from materials free from noxious orders or vapors, nor having a pliable character which does not collapse and yet does not resist filling by breathing into bags made therefrom.

Summary of the invention The principal object of this invention is to provide an inexpensive, portable, light-weight breath collection means including a nonrestrictive two-way piston valve having an integral mouthpiece for use by a patient, the valve permitting easy change from free breathing to the atmosphere to breathing into a plastic collection bag, and the bag being of composition, size, pliability, impermeability to gas, freedom from harmful vapors, and of a suitable surface and texture to receive the breath sample with only slight back pressure, and to retain the gas unchanged until samples thereof are withdrawn as from an exit valve for chemical and clinical analysis. It is intended that the device be used one time or for a single patient and be then discarded.

Claims are also directed to the nonrestrictive valve 3,426,745 Patented Feb. 11, 1969 structure per se because of the advantages of its use with other equipment.

Brief description of the drawing FIG. 1 is a perspective view of a preferred form of breath collecting bag means including a nonrestrictive piston mouthpiece valve, and an exit valve;

FIG. 2 is a fragmentary side elevational view of the device shown in FIG. 1, with parts broken away to show the piston valve in full open position to the bag;

FIG. 3 is a top view of the same showing the piston valve in position to close off the bag and permit air entering by the mouthpiece to flow to atmosphere around the piston stem;

FIG. 4 is a cross-sectional view taken on the line 44 of FIG. 2;

FIG. 5 is a cross-sectional view taken on the line 55 of FIG. 2;

FIG. 6 is a fragmentary side-elevational view partly in section showing the exit valve in the bag;

FIG. 7 is a side elevational view partly in section showing an alternative form of a quick change, nonrestrictive piston valve; and

FIG. 8 is a cross-sectional view taken on the line 88 of FIG. 7.

Description 0 preferred embodiments Referring to the drawings, a preferred form of the breath collection bag means of this invention is shown in FIGS. 1 to 6, and an alternative form of a quick-change nonrestrictive piston valve is shown in FIGS. 7 and 8.

The breath collection bag means consists of a pliable bag 11 which is provided with an intake valve 12 and an exit valve 13. The pliable bag 11 consists of two thin synthetic plastic sheets 14 and 15 of pliable and only slightly elastic sheet material which are joined at the contiguous edges by a welded seam 16. An opening or neck 17 is formed in one corner of the bag for attachment around the orifice 18 of the intake valve body 19, a bead 20 on the outside of the body 19 and an adhesive band 21 being provided to secure the connection between the bag neck 17 and the valve body.

The intake valve 12 is fabricated from molded synthetic resin parts and consists of the cylindrical body 19 which has a mouthpiece 22 extending outwardly from the central portion of the body, the mouthpiece preferably being elliptical in cross-section. A piston 23 is slidably mounted within the body 19, having terminal positions on either side of the mouthpiece opening, so that when the piston 23 is in its position nearest the orifice 18, the bag 11 is closed off from the mouthpiece 22 (FIG. 3) and when the piston 23 is at its outermost position the mouthpiece 22 communicates without restriction with the bag 11 (FIG. 2). A piston rod or stem 24 having an H cross-sectional shape (FIG. 4) is attached at one end to the piston 23 and at the other end there is provided an end disk 25, which serves as a finger grip means in the manual operation of the valve. A guide bar 26, of T shape in crosssection, extends endwise from the valve body 19, parallel to the piston stem 24, being attached adjacent the mouthpiece 22. The end disk 25 on the piston stem 24 is notched as at 27 so that it engages the cross bar 28 of the T guide bar 26, thereby keeping the piston in proper alignment during its operation. An outer stop means 29 is provided on the guide bar 26 at its outer end to keep the piston within the valve body, and an inner stop means 30 is provided on the guide bar to stop the inward movement of the piston and stem when the piston has closed off the communication between the mouthpiece and the bag. The outer stop means 29 is preferably in the form of a fiat end disk which also serves for the thumb back pressure when the valve is being opened by the operators fingers. For a similar purpose in moving the piston rod and piston inwardly, wing tabs 31 are provided integrally at the outer end of the valve body 19, and in this movement of the valve, thumb back pressure is applied on the end disk 25 on the piston rod 24.

The alternative nonrestrictive valve 12a shown in FIGS. 7 and 8 consists of a cylindrical body 19a having a side tubular mouthpiece 22a. A piston 23a is slidably fitted by means of sealing rings 32 to the inside walls of the body 19a, and is movable by means of the piston rod 24a which consists of longitudinally disposed crossed fins 33 which form a rigid stem and keep the piston 23a aligned axially in the cylindrical opening in the body 19a, and yet allows free air flow out of the cylinder around the fins 33. An end disk 25a serves as handle means for the manual operation of the piston. The mouthpiece 22a is disposed so that the piston 23:: may be positioned in the cylinder on either side thereof, to give unrestricted flow of air from the mouthpiece, either to the atmosphere, or alternatively to a bag 11a connected to the valve body. An inner stop means 30a is provided on the portion of 19a that extends within bag 11a, and the extent of inward movement of piston 23:: is defined by the abutting of rings 32 against stop means 30a, as shown in FIG. 7.

In both the preferred and the alternate forms of the piston valve, the opening the mouthpiece at its connection with the cylindrical valve body is not substantially less than the cross-sectional area of the exhaust air channels around the piston rods, so that there is no back pressure when the breathing into the valve passes to the atmosphere.- In general the cross-sectional area of the piston rod is not more than about ten percent of the crosssectional area of the body cavity.

The exit valve 13 (shown particularly in FIG. 6) consists of a relatively small synthetic resin tubular body 36 in which is disposed, across the opening therein, a diaphragm 37 of needle-puncturable self-sealing synthetic plastic material. The valve body is fitted into an opening in the seam 16 of the bag 11, and is preferably sealed thereto by electronic welding. To remove a sample of the gas from the bag, a hypodermic needle with attached syringe is pushed through the diaphragm and the desired gas sample drawn into the syringe. The diaphragm is substantially self-sealing when the puncturing needle is withdrawn.

The valve structures are made by plastic molding processes using styrene or similar plastic resin material, following the usual practice.

The collection bag is preferably made from polyvinyl chloride sheets (for example Ultron UL-40 produced by Monsanto Corporation). The preferred sheet material is approximately 0.006 inch in thickness and is free from any noxious odors or surface particles which might be released in use. The sheets are preferably jointed at the edges by electronic welding. The bag is shaped so that it does not collapse at the neck and shut off the entry of the patients breath, either when breathing or when being used in the rebreathing procedure. The bag preferably is made to contain about 4 liters of gas without appreciable back-pressure.

I claim:

1. A breath collection device adapted for single use and discarding comprising,

(a) a pliable gas-impervious bag having an intake opening formed thereon,

(b) a nonrestrictive intake piston valve secured to said intake opening, said val e i cl ding (1) a body having a cavity of uniform dimensions extending therethrough with one end thereof opening into said bag and the opposite end thereof communicating with the atmosphere,

(2) an integral mouthpiece attached to said body at an intermediate position along its length,

(3) a piston attached to a piston stern movable within said cavity to end positions on either side of said mouthpiece to establish communication between said mouthpiece and the atmosphere in one end position and to establish communication between said mouthpiece and said bag in the other end position,

(4) guide means integral with said valve body and extending parallel to the wall of said cavity, and

(5) coacting means formed on said piston stem for cooperation with said guide means to guide the movement of said piston stem parallel to said cavity within said body.

2. The breath collection devices as defined in claim 1 wherein the coacting means on said piston stem comprises a disk secured to one end of said stem, said disk having a notch therein which slidably engages said guide means.

3. The breath collection device as defined in claim 1 wherein said piston stern has a cross-sectional area not exceeding more than ten percent of the cross-sectional area of said body cavity.

4. The breath collection device as defined in claim 1 wherein said guide means comprises a T-shaped bar.

5. The breath collection device as defined in claim 1 wherein said T-shaped bar has an outer stop means at the outermost end of the bar for limiting the extent of outward movement of said piston and stem from within said cavity.

6. The breath collection device as defined in claim 4 wherein said T-shaped bar has an integral inner stop means provided thereon for limiting the extent of inward movement of said piston and stem within said cavity.

7. The breath collection device as defined in claim 1 wherein said bag is provided with an exit valve disposed away from and independent of said piston valve, said exit valve including a tubular member having a needlepuncturable self-sealing member disposed thereon.

8. A breath collection device adapted for single use and discarding comprising (a) a pliable, gas-impervious bag having an intake opening formed thereon,

(b) a nonrestrictive intake piston valve secured to said intake opening, said valve including (1) a body having a cavity of uniform dimensions extending therethrough with one end thereof opening into said bag and the opposite end thereof communicating with the atmosphere,

(2) an integral mouthpiece attached to said body at an intermediate position along its length,

(3) a piston attached to a piston stem movable with said cavity to end positions on either side side of said mouthpiece to establish communication between said mouthpiece and the atmosphere in one end position and to establish communication between said mouthpiece and said bag in the other end posilton,

(4) said piston stem consisting of integral crossed fins whose outer edges slidingly engage the walls of said cavity to guide the movement of the piston stem, and

(5) said valve body including stop means disposed adjacent at least one end thereof on the wall defining said cavity, said stop means limiting the extent of movement of said piston and said stem within said cavity.

5 6 References Cited OTHER REFERENCES UNITED STATES PATENTS Cooper, E. A., and Pask, E. A.: The Lancet (p. 369),

Feb. 13, 1960.

2,702,034 2/1955 Walter 128272 Peters, J. P., and Van Slyke, D. 1).; Quantitative 2,795,223 6/ 1957 Stampe 128-2 Clinical Chemistry, vol. 11, Methods, 1932, The Williams 2,867,511 1/1959 Harger 23254 5 and Wilkins 00., Baltimore (pp. 174-175 relied on). 2,902,992 9/1959 Renvall 128-145] 3 747 12/1963 Cowley 12 218 GAUDET, Przmary Examlner- 3,196,689 7/1965 Forrester et a1. 73- 1-215 KYLE L, HOWELL, Assistant Examiner, 3,303,840 2/1967 Etzlinger 1282 3,321,976 5/1967 Jones 73- 1215 10 3,338,087 8/1967 Moberg et a] 73-4215 73421.5; 128-2.07

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