US 1630501 A
Description (OCR text may contain errors)
May 31, 1927. 1,630,501
M. C. STEESE LIFE SAVING APPARATUS Fled April 12. 1920 Patented as 31, 1927.
mucus c. s'rnnsz, or nunurn, mnnso'ra.
' run-swine Arrmrus Application filed April 12,1920. Serial no. awa ts. I
My invention relates to life-saving apparatus, such as is used in mines and other places Where gas is prevalent, whereby thewearer of the apparatus may safely enter places where otherwise he would be subjected to danger of injury, if not death. More particularly the invention relates toapparatus including a supply of. oxygen and means connecting the oxygen supply with the respiratory organs of the wearer in such manner that the wearer may have a suflici'ent supply of oxygen at all times regardless of the amount consumed. The apparatus 1s provided with means for exhalation as well as inhalation, the usual type of apparatus including a bag preferably suspended in front of the wearer and connected by suitable means to the mouth and nose of the wearer, means within the bag) for absorbing the carbon-dioxide exhaled y the wearer, and means for preventing its admission to the inhalation portion of the apparatus.
It is a well-recognized fact that the inhalation and exhalation of a human being varies according to the exertion of that erson. The amount of oxygen inhaled an exhaled when a person is exercising or working hard is greater than under normal conditions.
I am aware that various kinds of apparatus have been devised for supplying oxygen to a person, but such do not function I satisfactorily under all conditions. At the present time there'aretwo types of apparatus used. In one form a constant flow of oxygen is supplied to the wearer, which-supply is more than suflicient to supply the oxygen consumed when the wearer is not exerting himself, but which is below the amount required when the wearer is exerting himself violently. In such ap aratus it is necessary to provide means or throwing ofl the excess amount of oxygen supplied, which results in a material waste of oxygen. To take care of the increased supply demanded when the wearer is exerting himself, a manually controlled valve is provided in the apparatus. The other type of apparatus is what is known as a variable flow apparatus and is so constructed that the rate of flow of the oxygen varies with the consumption. This regulation is accomplished by the opening and closing of an auxiliary valve which is operated by a bellows. The chief object-ion to this type of apparatus is that the openings in the auxiliary valve must necessarily thereof.
very small, the result being that these small openings become clogged very easily, thus impairing the efliciency of the apparatus and endangermg the life of the wearer by cuttin g off the flow of oxygen whenfthe same is needed. i
My invention finds particular application in that type of apparatus wherein the supply of oxygen is responsive to the consumption.
- An object of my invention is the provision of alife-saving apparatus of the class described whichis of simple construction and in which the oxygen supply is made responsive to the variations in breathing of the wearer so as to supply the requisite amount of oxygen at all times.
Another object is to provide an ap aratus of the class described which will urnish oxygen in proportion to the consumption A further object is to provide an apparatus which will be as simple in mechanical construction as is practicable, and one in which there are no outside moving parts and in which there are no small apertures through which the oxygen must pass, thereby removing the possibility of clogging and the endangerin .of the life of the wearer.
These and 0t er objects are accomplished by means of the arrangement disclosed on the accompanyin sheet of drawings, which.
shows in somew at diagrammatic form a life-saving apparatus in which are incorporated the features of my invention.
Oxygen cylinders 1 are arranged to be carried preferably on the back of the wearer in any desirable manner. In these cylinders the oxygen is contained at high pressure. A tube 2 in communication with the oxygen linders 1 has the supply of oxygen theret rough controlled by means of a main valve 3 and in part by a reducing valve 4. Interposed between the valves 3 and 4 is a pressure gauge valve 5 which is connected by means of a pressure gauge tube 6 to a pressure gauge 7 carried on the bag 8. Around the reducing valve" 4 is a by-pass valve 9 which on being opened ermits oxygen to 4 pass to the discharge si e of the pressureoxygen is led into the breathing bag 8 by means of a supply tube 10. In my arrangement the portion 11 of the oxygen supply pipe referably is inside the breath ng bag 8 and projects downwardly a considerable distance therein and has an upturned end 12 which enters a Venturi tube 13 and has 1ts discharge end terminating within the Venturi tube 13 at the point of greatest restr1ction of the latter. The Venturi tube 13 is connected by a flexible tubing 14 to the mouth-piece 15, which is secured to the head of the wearer in any suitable manner. From the mouth-piece an exhalation tube 16 extends to the breathing bag 8. This breathing bag 8 is provided with a flexible partition 18 which extends from the top of the bag to almost the bottom thereof, so that for all intents and purposes the bag may be considered as being divided into two portlons by means of the partition 18. The inhalation tube 14 is connected to the breathing bag 8 on one side of the partition and the exhalation tube 16 on the other side thereof. In the bottom of the ha a quantity of canstic soda 19 or other car onic acid absorbent is placed in such quantit as to extend above the bottom ofthe partition 18 and thus prevent the flow of gas from either side of the partition without necessarily having to pass through the absorbent. An exhaling relief valve 17 is provided which may be adjusted by the wearer as occasion demands.
The operation of the apparatus wlthout the Venturi tube 13 may be'described briefly as follows In such a case the reducing valve 4 would become a constant flow valve and be set to permit the flow of approximately two litres of oxygen per minute. The main valve 3 being opened, ox gen from the cylinders 1 would pass theret rough, then to the valve 4 and through oxygen supply pipe 10 to the breathing bag 8. The supply of oxygen necessarily distends the bag 8 and if there were no consumption of oxygen this supply would have to be relieved by means of the valve 17 It will be understood that the inhalation tube 14 is in communication with one of the portions formed by the partition 18, while the exhalation tube 16 is in communication with the other portion, which is standard in all bags of this general type. When the wearer is breathing, the oxygen supplied to the bag is inhaled through the tube 14 and exhaled through the tube 16, the carbonic.
acid passing through the absorbent 19 and being absorbed thereby, the volume within the bag being augmented by the constant flow of oxygen delivered thereto. In case of violent exertion, the two litres of oxygen are insufficient to sup ly the requisite amount of oxygen, an accordingly the wearer manipulates the by-pass valve 9 to admit an excess supply of oxygen to the bag from time to time to make up for the deficiency caused by the constant flow of two litres.
However, as stated before, in the apparatus of my invention, the extension 11 of the oxygen supply pipe 10 projects into the bag with the delivery end 12 thereof projecting into the Venturi tube and termmatin at the point of greatest restriction. Wit
this arrangement the reducing valve 4 serves as a variable flow valve set to discharge at a constant pressure; that is to say, if the pressure in the oxygen supply pipe 10 is increased or decreased, the flow through the valve 4 will be correspondingly increased or decreased. This reducing valve is the regular standard type of reducin valve used for many purposes in the use of steam, air and other fluids. There is nothing peculiar about the construction of said valve in this case. The reducing valve is set to discharge oxygen'at a constant pressure, said pressure being sufficient to dlstend the bag to its working pressure; namely, five centimeters of water gauge, whereupon the flow through the reducing valve stops and no further oxygen flows therethrou h until a reduction in pressure takes place in the tube 10. Accor ingly, as the inhalation of the wearer increases or diminishes a corres nding increase or decrease of suction t rough the Venturi tube is caused, this suction necessarily acting to control the supply of oxygen through the ipe 10. If the pressure at the end of the plpe 12 is decreased the flow of oxygen thereto would necessarily be increased as the pressure of oxygen delivered through the valve 4 is constant. The suction through the Venturi tube is a function also of the velocit of the flow therethrough, the result being that increased inhalation causes a corresponding increase of the supply of oxy en, which supply is responsive absolute y to the variations in the breathing of the wearer. It is apparent, therefore, that air drawn through t e Venturi tube 13 will gpeatly increase in speed at the point of greatest restriction, causing a suction in the 0 gen supply extension 12 and causing the re ucing va ve to open for supplying oxygen with an amplifyin action.
I might state t at in the constant flow type of ap aratus, an injector principle is made use 0% in which the pressure of oxygen from the cylinders is reduced by a reducing valve to-asomewhat lower pressure and then passed through a minute nozzle or orifice introduced into an injector which causes the air and carbonic acid to circulate independently of the breathing of the operator. In short, in the injector type of apparatus the flow of oxygen causes a circu ation of respiratory gases. In my apparatus, using the Venturi and the constant pressure reducing valve combination, the flow of respiratory gases through the breathing bag in response to the demands of the wearers lungs, causes an increase or decrease in the flow of oxygen.
My invention has eliminated moving parts Which easily become disorganized and cause inefficient functioning of the apparatus and constant danger to the life of the wearer. Furthermore, I have secured a variable oxygen supply with the elimination of the small apertures and by-pass valves, and there is nothing in my arrangement which will become easily disorganized or put out of order by rough usage or constant demands on the system.
While I have described more or less precisely the details of construction of my invention, I do not wish to be understood as limiting myself thereto, as I contemplate changes in form, the proportion of parts and substitution of equivalents as circumstances may suggest or render expedient, Without departing from the spirit of my invention.
I claim: 1.. In a device of the class described, a
source of oxygen supply, a valve operatively associated with said source, a Venturi tube, and a connection between said source and said Venturi tube including said valve, said connection terminating in a relatively large opening at the point of greatest restriction of said Venturi tube for controlling said valve and the supply of oxygen from said source.
2. In a device of the class described, a source of oxygen supply, a Venturi tube directly connected by piping to the mouth of the wearer, pressure reducing valve connect ed to the source of ox gen supp] and piping leading from sai valve an terminating in an opening of relatively large size within the restricted portion of the Venturi tube, whereby the valve is responsive to suction created in said portion of the tube by the wearer.
Signed at Chicago, Illinois, this 29th day of March, 1920.