Jan. 21, 1947. K|RSCHBAUM 2,414,747
METHOD AND APPAIKATUS FOR CONTROLLING THE OXYGEN CONTENT OF THE BLOOD OF LIVING ANIMALS Filed July 2, 1942 MOTOR INVENTOR. HARRY M..KIRSCHBAUM ATTORNEYS Patented Jan. 2!. i941 2,414,747
UNITED sures PATENT OFFICE METHOD AND APPARATUS FOR CONTROL- LING THE OXYGEN CONTENT OF THE BLOOD OF LIVING ANIMALS Harry M. Kirsohbaum. Detroit. Mich. Application July 2, 1942, Serial No. 44am 1 claims. (or. 128-142) l The invention relates to means for automatically controlling the oxygen content or the blood in living animals, being more particularly designed i'or use by aviators; but also adapted for 2 duit. C is a control valve and D a conduit leading from the valve to a nose piece E. or other means for administering the gas to the subject. The automatic operating means for the valve use in hospitals and in other places. 5 may be of any suitable construction, either me- It is the object of the invention to introduce chanical or electrical, which is under the control oxygen into the lungs of the subject when needed, or means sensitive to blood changes. As illusthis being determined automatically by the contrated, the valve is periodically opened by a timdition oi his blood. To this end the invention ing mechanism which is actuated by an electric consists in the method and apparatus as hereinmotor whenever the latter is energized. F is a after set forth: motor and G a step-down transmission mecha- In the drawing: nism including a rotating crank H provided with Figure 1 is a diagrammatic view of an appaa crank pin I. J is a slidable member for openratus for carrying out my invention; ing the valve which extends into the path of the Figure 2 is an enlarged view of the control pinI so that once in each revolution of the crank means;
Figure 3 is a section through the control valve; and
through which the oxygen is supplied.
comes darker when it loses its oxygen content. Making use of this, I have devised a means of controlling an oxygen administering apparatus by the color or light absorption capacity of the blood circulating through a, portion of the animal tissue. For instance, in the lobe of the ear there are minute blood vessels or capillarieg through which blood is constantly circulating. y directare connected to each other by a resilient loop-N ing a beam of light through this tissue the charso that they may be clamped against opposite acter of the light will be modified by the color sides of the lobe of an ear, 'as indicated at 0. of the blood which'intercepts its path. A light The specific construction of the elements L and sensitive electric cell exposed to this beam will M is not a part of the instant invention. The respond to such changes so that in connection with element L is, however, of such a character as to suitable amplifying'and relay means itis adapted be responsive to changes in the character of light to operate a valve controlling the oxygen supply. falling thereupon. As the source of light is in The oxygen may be introduced into the lungs of the element M on the opposite side of the lobe the subject by any suitable means such as a of the ear, it. must be transmitted through said flexible conduit leading to a nose piece. Thus 40 lobe and thus is aflected by the color or opacity when the blood is in normal condition the oxyofthe blood circulating through the capillaries. gen supply is cut off, but whenever the blood is Thus a change from the bright red of oxygenated insuflicientlv oxygenated its change in character blood to the darker bluish color of blood deficient will automatically bring about an opening of the in oxygen will aflect the current generation in valve and without any attention on the part of the the element L. This current passes through consubject. This renders it particularly adapted for ductors P to the amplifying means Q, which also use by aviators, whose attention is frequently so may be of any suitable construction, and the amconcentrated on the control 01 the machine as to plifled current actuates arelay switch R; concause them to neglect turning on the oxygen trolling the supply of current to the motor F. supply when needed. The arrangement is such that the switch R is Various forms of apparatus may be used for carrying out my invention. but as diagrammatically illustrated, A is a conduit leading from a source of oxygen supply. B is a means for regu- Figure 4 is a section through the nose piece the valve will be opened. This valve, as illustrated, comprises a casing K having an inlet port connected to the conduit Aand an outlet port connected to the conduit D. Within the casing is a valve seat K located between the inlet and outlet ports, and a valve K connected to a plunger K is normally held to its seat by the tension of a spring K The slide J is connected to the stem K and thus whenever it is displaced by the pin I, the valve K will be-liited from its seat to permit flow of oxygen item the conduit A to the conduit D.
The controlling means comprises a light-sensitive cell L and illuminating means M. These open when the blood is in normal condition and thereby starting the motor F and periodically actuating the valve K.
lating the rate oi now 0! gas through said con 5s The timing oi the actuating mechanism is preterably such as to correspond approximately with the breathing cycle of the subject, so that a pulse of oxygen is admitted with each inhalation of the breath. It is not, however, necessary that the oxygen should be supplied in pulses as the valve may remain open continuously during the pe-. riod in which oxygen is needed' The advantage of the pulsating operation is that the quantity of oxygen supplied may be more easily regulated.
For convenience in use, the control-means L,
M and the nose piece or nozzle E may be mounted on a head frame S which holds them in proper relative position. A gauge T may be used in connection with the amplifying means Q to vis-- ually indicate the current variation due to blood changes.
For use by aviators it may be necessary to adjust the device to correspond to individualcharacteristics. Such adjustmentmay be effected while the subject is on the ground and may be used in connection with other testing means for individual responses. When such adjustment is made the aviator may be assured that it will respond in a similar manner when he is in the air thereby avoiding any danger of lack of oxygen when it is needed. I
What I claim as my invention is: V
1. In a method of controlling the oxygen contentin the blood of a living animal, the steps of modifying a light beam by variations in light absorption capacity of a portion of the animal tissue through which blood is circulating, varying an electrical current by said modified light beam and controlling the introduction of oxygen into the lungs of the animalby said variations in current.
of the subject, andmeans for controlling said supply by the current from said cell.
4. An apparatus for automatically controllin the oxygen content in the blood of a living animal comprising a photo-electric cell, a member containing a, light source, lmeans for clamping said cell and member on opposite sides "of a portion of the animal tissue in which blood is circulating, and means for supplying oxygen to the lungs of the animal controlled by the current from said cell. 5. An apparatus for automatically controlling the oxygen content in the blood of a living animal subject comprising a photo-electric cell,'a member containing a source of light, means for clamping said cell and member on opposite sides of a portion of the tissue of the subject in which blood is circulating, means for supplying oxygen to the lungs of the subject, and means controlling said supply in itself controlled by said photo-electric cell. 7 j
6. An apparatus for-automatically controlling the oxygen content in the blood of a living animal '2. In a method of controlling the oxygen con- I tent in the blood of a living animal, the steps of transmitting light through a portion'of the animal tissue in which'the blood is circulating, and
directing the transmitted light upon a photoelectric cell whereby the current generated by said cell is varied in accordance with modifications in the blood due to deficiency in oxygen, and controlling the introduction. of oxygen into the lungs of the animal by said current variations.-
3. An apparatus for automatically controlling subject comprising a photo-electric cell, a member containing a source of light,-means for clamping said" cell and member on opposite sides of a lobe of an ear of the subject whereby the light transmitted through said lobe will be modified by changes in the blood circulating through said lobe due to oxygen deficiency, an oxygen supply, a conduit leading from said supply connecting with the. lungs of the. subject, a valve control-' ling admission of oxygen from said supply to said conduit, and means controlled by the current generated in said photo-electric cell for operating said valve.
'7. An apparatus for automatically controlling the oxygen content in'the blood of a living animal subject comprising a photo-electric cell, a member containing a source of light, means for clamping said cell and member on opposite sides of a lobe of an ear of the subject whereby the light transmitted through said lobe will be modified the oxygen content in the blood of a living animal subject, comprising means for transmitting light through a portion ofv the animal tissue in which blood is circulating, a photo-electric cell positioned to receive the transmitted light whereby the current generated by said cell will be varied in accordance'with modifications in the transmitted light due to modifications in the blood stream, means for supplying oxygen to thelungs HARRY M. KIRSCHBAUM.