US 3362420 A
Description (OCR text may contain errors)
Jan. 9, 1968 C. M. 4BLACKBURN ETAL ANTI-SUFFOCATION VALVE Filed Aug. ll, 1965 man n www N Y NG n r. E A 0. N VMM J m@ AWA MSV.. $0 R RH P HR a n m mw vm mw E d r .n Jw/ hv um um mm Q 2l mm n. vm .5.. mm *I 1 mm l. E Nol om .mwll ||||w| E K g 2, mw \V\` n \N il. w .3. bv Q V mm Vi m uw 7 /mr mw G mm ,I Km mw mm No mw United States Patent O 3,362,420 ANTI-SUFF CATION VALVE Charles M. Blackburn and Richard S. Brasllears, Silver Spring, Md., assignors to the United States of America as represented by the Secretary of the Navy Filed Aug. 11, 1965, Ser. No. 479,021 Claims. (Cl. 137-81) ABSTRACT OF THE DISCLOSURE There is disclosed a safety valve for automatically venting an oxygen mask to the atmosphere in the event that the oxygen supply becomes depleted while the wearer is unconscious and further provides that the valve will not automatically vent to the atmosphere if the wearer is above a predetermined altitude or submerged in water.
The present invention relates to an anti-suffocation valve and, more particularly, to a valve for an oxygen mask which prevents suffocation when the wearer is unconscious.
It is the continuous desire of developers of oxygen masks, flight helmets, and other similar life supporting equipment to make them safer for those who use them. However, the equipment that is available today does not have a safety feature that enables the artificial respiration system to be vented automatically to the atmosphere in the event that the system becomes depleted of oxygen when the wearer is unconscious. Such a safety feature would be desirable in the event that the oxygen supply was depleted yet the wearers altitude was such that adequate respiration could be maintained by the ambient at- Inosphere. Of course, if the wearer is conscious, he would merely remove the mask or helmet. The problem arises, however, when the wearer is unable to do so, for example, when he is unconscious. It is, therefore, desirable to provide a device for automatically venting the respiration system to the atmosphere when the oxygen supply falls below a predetermined level. Of course, if the ambient atmosphere is not capable of supporting adequate respiration, the system should not be vented thereto. This would occur, for example, when the wearer is either above a predetermined altitude or momentarily submerged in water.
It is, therefore, an object of the present invention to provide an anti-suffocation valve for automatically venting an artificial respiration system to atmosphere should it become depleted of oxygen.
Another object is to provide an automatically venting valve which is prevented from venting to the atmosphere when in use above a predetermined altitude.
Still another object of the present invention is to provide a valve which is prevented from venting to the atmosphere when submerged in water.
A further object of the invention is the provision of an automatically venting valve which is characterized by simplicity of construction, reliability, low cost and ease of installation.
Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings in which:
FIG. l is a side elevation view, partly in section, of a preferred embodiment of the invention;
FIG. 2 is a side elevation view of a breathing mask incorporating the instant invention; and
FIG. 3 is a schematic View, partially in elevation, of a portion of the invention.
Referring now to the drawings wherein like reference characters designate like or corresponding parts throughout the several views, there is shown in FIG. 1 a generally cylindrical housing 5 having a longitudinally flattened portion 6 and a flange 7 to facilitate mounting the housing 5 to the interior of a breathing mask or helmet 8 used in an artificial respiration system. The housing 5 is provided with a chamber 9 which is closed at one end by an integral end wall 11. At its opposite end, the housing -5 is threaded internally to receive a solenoid mounting plate 13 having a solenoid 15 attached thereto as by a screw 17.
A valve element 19, mounted in the chamber 9, has an internally threaded base 20 that threadedly engages a reduced threaded boss 21 extending axially from the inner end of the solenoid 15. The valve element 19 has a tubular central wall 22 extending from the base 20 and terminating in an outwardly directed flange 23. Mounted within an annular groove 24 on the outer surface of the flange 23 is a sealing ring 25 for sealing the annular space between the valve element 19 and the housing 5. The inner wall of the valve element 19 is flared outwardly toward its inner end to define a Valve seat 26 while the tubular central wall 22 of the valve element 19 is provided with a pair of ports 27. The housing 5 is also providedV with a pair of ports 29 and 31, Iport 29 opening to the ambient atmosphere and port 31 opening into the interior of the helmet 8. In a manner to be explained, the ports 29 and 31 may be selectively placed in communication with each other to enable the ambient atmosphere to enter the interior of the helmet when the artificial oxygen supply becomes depleted.
The solenoid 15 actuates a plunger 33 attached by a screw 35 to a disc shaped valve member 36 which is movable into engagement with the valve seat 26 lby the movement of the plunger 33. The disc shaped valve member 36 includes a toroidal sealing element 37 which abuts the valve seat 26 when the valve is closed. A retaining ring 38 is clamped between the inner end wall of the plunger 33 and the sealing element 37, thereby securing the element 37 against the valve member 36. The valve member 36 is urged toward an open position by a spring 39 which is coaxially mounted around the solenoid plunger 33 and is confined between the inner surface of the Ebase 20 of the valve element 19 and the confronting face of the sealing element 37.
Abutting the valve member 36 is a bi-chambered bellows 41 disposed between the valve member 36 and the end wall 11 of the housing. The bi-chambered bellows 41 is divided into two adjoining bellows 43 and 4S by a common wall 46 while each is closed at its outer end by the end walls 47 and 48, respectively. The outer wall 47 abuts the valve member 36 and the bellows 43 is permanently lled with a gas, such as nitrogen, to form a pressure cha-mber. The outer wall 48 of the smaller bellows 45 is connected to a mounting plate 49 which is secured to the end Wall 11 by screw rneans 54. A tubular spacer 50 is attached to the inner surface of the outer wall 48, and extends axially through the bellows 45 towards the common wall 4-6.
A port 51 extends through the outer wall 48 and the mounting plate 4'9 to vent the spacer 5) and the interior of the bellows 45 to the passageway 53 in the end wall 11. A ring gasket S5 is contained in an annular groove 56 on the mounting plate `49 to seal the passageway 51 from the chamber 9. A second spacer 518 is axially mounted, as by welding, to the common wall 46 of the larger bellows 43, which spacer limits the collapsing motion of the larger bellows 43 by acting as a stop against the outer wall 47. In a similar manner, the tubular spacer 50 limits the collapsing motion of the smaller bellows 45'.
Referring now to FIG. 2, the interior of the breathing mask 8 is supplied with oxygen from an external so-urce 59 through a pressure regulator 60. The oxygen supply 59 is also directly connected by aline 61 to the passageway 53. In operation, the pressure of the -oxygen from the source 59 passes through the line 61, the passageway 53, and the tubular spacer 50 to the interior of the bellows 45. This pressure expands the smaller bellows 45, thereby moving the valve member 36 against its valve seat 26. This movement prevents communication between the atmosphere port 29 and the interior port 31 until the pressure of the oxygen source drops below a predetermined value, wherein the force exerted by the smaller bellows 45 is overcome by the spring 39 and the valve member 36 is opened. However, should the oxygen source become depleted when the altitude of the aircraft is such that the ambient atmosphere is insufficient to sustain adequate respiration, the larger bellows 43 would, notwithstanding the drop in oxygen pressure within the bellows 45, maintain the valve member 36 firmly seated against the valve seat 26, thereby preventing venting of the breathing mask 8.
As illustrated in FIGS. 1 and 2, the ambient atmosphere port 29 is surrounded by a pair of annular metallic rings 63 and 64 contained in the grooves `66 of an annular nonwetting gasket 65'.
As illustrated in FIG. 3, the outer ring 63 is connected in series with an energy source 62, such as a battery, and one of the terminals of the solenoid while the inner ring 64 is connected to the -other terminal of the solenoid 15. If the wearer of the mask 8 should be momentarily submerged under water and unconscious when the oxygen supply becomes depleted, he would be in grave `danger if the port 29 were opened. Therefore, in such a situation, the water will complete the series circuit by forming a conductive path between rings 63 and `64, thereby driving the plunger 33 into the solenoid to seat the valve member 36 and prevent water from entering the interior of the valve through ports 29 and 31. When the mask is removed from the water, the non-wetting properties of the gasket 65 will again open the series circuit and allow the interior of the valve to vent to atmosphere.
Obviously, many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.
What is claimed is:
1. An anti-suffocation valve for use in an artificial respiration system having an oxygen supply comprising:
a tubular housing having a pair of axially spaced ports therein;
a solenoid having a plunger, said solenoid being secured to one end of said housing;
a valve element secured to said solenoid, said Valve element having a valve seat disposed between Said ports;
a valve member secured to said solenoid plunger, said valve member abutting said valve seat when said solenoid is energized to thereby close communication between said ports;
a spring concentrically mounted around said solenoid plunger for urging said valve member away from said valve seat;
a bellows having first and second chambers therein, said first chamber being secured to the other end of said housing and said second chamber abutting said valve member, said first chamber having an axially ydisposed tube therein extending throughout a substantial portion of the length of said chamber, said tube being in communication with a passageway through said housing which is adapted to be pressurized by said -oxygen supply, said second chamber having an axially disposed tube therein and being filled with a gas so as to define a pressure chamber; and
a pair of metallic .rings disposed around one of said ports, said rings being separated by a non-wetting gasket and being electrically connected to said solenoid for actuation thereof when said rings are submerged in water;
whereby said Valve member is normally held against said valve seat by the pressure of the oxygen in the first chamber of said bellows but will separate when said oxygen is depleted unless the altitude is such that the ambient atmosphere will not sustain adequate respiration or the rings are submerged in water.
2. An anti-suffocation valve comprising:
a housing having a pair of ports therein;
valve means adapted to open and close communication between said ports;
resilient means urging said valve means towards an open position;
first pressure means in communication with a respirant supply for maintaining said Valve closed when the pressure of said supply is above a .pre-determined value;
secon-d pressure means for maintaining said valve closed fwhen the ambient pressure is below a pre-determined value; and
means for maintaining said valve closed when submerged in Water.
3. An anti-suffocation valve, las set forth in claim 2,
wherein said first and second pressure means comprise:
a bi-chambered bellows, one end of which abuts said valve means and t-he other end of which is secured to the end wall of said housing.
4. An anti-suffocation valve, as set forth in claim 3, wherein said means for maintaining said valve closed when submerged in water comprises:
a solenoid having a plunger secured to said valve means; and
an electric circuit for operating said solenoid, said circuit including a normally open switch which is adapted to close when submerged in water.
5. An anti-suffocation valve, as set forth in claim 4,
wherein said normally open switch comprises:
a pair of metallic rings separated by an annular nonwetting gasket.
6. An anti-suffocation valve comprising:
a housing having a pair of ports therein;
valve means establishing communication between said ports when in :an open position;
first means in communication with a respirant supply for closing said valve when the pressure of said supply is above a predetermined value; and
second means responsive to water for maintaining said valve in a closed position when submerged in said water irrespective of the pressure of said supply.
7. An anti-suffocation valve, as set forth in claim 6,
third means for maintaining said valve in a closed position when the ambient atmospheric pressure is below a predetermined value irrespective of the pressure of said supply.
8. An anti-s-uffocation valve, as set forth in claim 7,
wherein said first and third means comprises a bi-chambered bellows.
5 6 9. An anti-sniocation valve, as set forth in claim 6, References Cited wherein said second means comprises: UNITED STATES PATENTS a solenoid secured to said valve means; and a pair of metallic elements electrically connected to 2387123 10/1945 Demmg 12g-*1465 said solenoid for energizing s-arne when said elements 5 2822816 2/1958 Schutmaat 137-80 are submerged in Wan 2,853,268 9/1958 Hu-glles 137-505.22 X 10. An anti-suffocation valve, as set forth in claim 9, 3092104 6/1963 Cassldy 12S-142 wherein said elements comprise:
a pair of rings disposed around one of said ports, said WILLIAM F' O DEA Prmary Examme' rings being separated by -a non-wetting annular 10. R. GERARD Assistant Examiner. gasket.