US 2408136 A
Description (OCR text may contain errors)
Sept; 24, 1946.
1 5 ROY G. Fox
RESUSCITATOR-INSUFFLATOR-ASPIRATOR Filed Dec. 7, 1942 y 4 Sheets-Sheet 1 Sept. 24, 1946. LE ROY G. Fox 2,408,136
RESU'SCIIATOR- INSUFFLATOR-ASPIRATOR Filed Dec. '7, 1.942 4 Sheets-Sheet 2 ff-Roy G. `0X
5M @I n. y I.
Sept. 24, 1946. LE ROY G. Fox
l RESUSCI TATOR- INSUFFLATOR-ASPIRATOR Filed Dc. '7,'1942 4 Sheets-Sheet 3 Sept. 24, 1946. LE Roy G. Fox l2,408,136
RESUSCITATOR-INsUFFLAToR-ASPIRATOR Filed DGO. 7, 1942 4 Sheets-Sheet 4 da n Patented Sept. 24, 1.946
a RESSCITATOR INSUFFLATQR Asrmn'ron Le Roy G.`Fox, Los-Angeles, Calif., assignor,` by mesne assignments, to E & J Manufacturing Company, Glendale, Calif., a
California corporation of Application December 7, 1942, Serial No. 468,079
v3 oiaims. (cl. 12a-29) l This invention relates which may be selectively operated as a resuscitator, an insuliiator and an aspirator.
United States Letters Patents Nos. 2,138,845 and 2,269,934 granted to C. N. vErickson on December 6, 1928 and January 13, 1942 respectively, show machines relative towhich the present invention embodies certain improvements, particularly as to'reduction of weight, size, and bulk;y greater nicety of control, dependable operation over a greater range or respiratory rates than heretofore, a novel valvularcontrol means affording simultaneous resuscitationV and aspiration operations as well Aas'selective operation of the machine asa resuscitator, an insuiator and an aspirator, together with other improvements and advantages whichwill be 'hereinafter pointed One of the objects of this invention vis to provide in a machine of the character described a breathing indicator in which an indicating member such as a ball conned in a transparent tube will rise and fall in correspondence to the inhalation and exhalation cycles of the machine during a resuscitation operation to show the depth of breathing of the patient; said ball fluttering rapidly when an obstruction is present in the respiratory tract of the patient, and in all, serving as an effective tell-tale whereby the operator may readily regulate the operation of the machine to best suit the rconditions at hand in a far more satisfactory manner than heretofore.
Another object of this' invention is to provide in a machine suchv` as described an indicator which when the machine is voperated as an insuillator will indicate the rhythm of the patients breathing, the ball of the indicator remaining elevated when the patient is receiving too much oxygen but rising and falling in correspondence with the breathing of the patient when the proper amount of oxygen is supplied, and not being elevated when too little oxygen is'supplied thereT by indicating accurately at all times the manner in which the machine'is operating and Apermitting the operator to make the necessary regulatory adjustments to insure thebest possible ation for the particular patient. Y
Another object of this invention is to provide a machine of Vthe character described in which the head of the machine is made as a'compact casting embodying a central body` portion inA which is provided a two-stage Vpressure regulator and toA which is connectedgin compact arrange GO portable resuscitators.
operment, the valves, diaphragmjVenturi devices and all. other working` parts ;v Athere being a yoke Y projecting from opposite sides of the vbody portion for supporting in connection with the machine two medicinal valve tanks for oxygen, which tanks are suspended in such manner as to eliminate all'possibility of breakage at the 10W pressure joints. the yoke and reducing Valve are made in a single high pressure casting wherein there are only three high pressure joints, one at the joint where the usual pressure gauge is screwed in,`and two at the joints where the check Valve bodies are screwed in.
One of the objects of my invention ris to provide a vresuscitator of the character described in which the negative pressure eifective of the exhalation action of the machine is created by means of a Venturi device of such form and ar-l rangement that the improvements embodied herein are achieved in a particularly ecacious manner with the added advantages of a most dependable operation with proper rhythm at a much lower 'pulmometric rate than heretofore.
Another objectof my invention is to provide a resuscitatorgsuch as described in which the oxygen or gas pass 'tothe patient through the venturi on the inhalation cycle of the machine without intaking atmospheric air through the Venturi and consequently objectionably diluting of the oxygen or gas.
Another object isV to provide a Venturi type of resuscitator wherein the venturi will instantly respond to a small amount of gas to create the desired negative pressure under a precise control by the Operator.
With the foregoing objects in view, together with such other objects and advantages as may subsequently appear, the invention resides in the parts and in the combination, construction and arrangement of parts hereinafter described and claimed, and illustrated by way of example 'in the accompanying drawings, in which:
Fig. 1 is a fragmentary front elevation of a machine embodying the present invention;
Fig. 2 is a fragmentary bottom plan view ofthe Moreover, with this arrangement omitted, broken away and in section to illustrate the two stage pressure regulator;
Fig. is a fragmentary bottom plan sectional view similar to Fig. 2 but showing the machine as when operating on the exhalation cycle, partie'- ularly the positions of the control valves and the paths of the iiuid; Y
Fig. 8 is a fragmentary cover part of the toggle chamber;
Fig. 9 is a front elevationrof thertorggle andV Y,
- l sure.
rear'elevati'on of the Fig. 10 and Fig. 11 are semi-schematic fragmentary sectional views of the toggle-diaphragm unit and the valves operated thereby and other control valves showing such parts as when the machine is operating on the inhalation (pres-y sure) and exhalation (suction) cycles respectively during anV ordinary resuscitation operation of the machine; Y
Fig. 12 is a fragmentary sectional View of the hose connection with the mask showing the manner in which the gas enters and discharges from the mask;
Fig. 13 is a semi-schematic section similar to Figs. 10 and 11 and showing the position of the toggle and valves related. thereto and other control valves as when the machine is operated as an insuiator and during the inhalation cycle;
Fig. 14 is a view corresponding to Fig.y 13 but showing the parts and valves as when the patient is exhaling following insufation.
General description chamber depends from the top portion as bestV shown in Figs. 1, 2, 3 and 4, and is horizontally disposed and supports in a compact arrangement all of the Workingparts of the machine.
Embodied in the cylinder 4 is a two-stage pressure regulator B while at the forward end of the cylinder in a removable toggle-diaphragm chamber C, as shown in Figs. 2, 10 and 11, is a diaphragm-operated valve means D which responds to variations of the pressures in the patients lungs to automatically control the inhalation and exhalation phases of the resuscitation cycle of the machine.
With reference to Figs. 1 and 2, it is seen that on the outer face of chamber C is the resuscitator control knob 5 for a resuscitator control valve 6 while adjacent said knob are the insuiliator control knob 'lfor the insufflator valve 8, and the aspirator control knob 9 for the aspirator valve Ill. On opposite sides of and opening into the chamber C `are safety check valves Il and I2 which open to the atmosphere responsive to predetermined positive and negative pressures, respectively, the. valve II opening when the positive pressure reaches for example six ounces while the Valve I2 opens at a negative pressure of four ounces.
The chamber C is connected to the mask M by means of flexible hose lines I3 and I4 (see Figs. l. and 10 to 14 inclusive). These hose lines are mounted one within the other to conserve space and protect said lines and are connected'to the chamber C by means of concentric hose connections I5 and I6 on the lower side of said chamber. The mask is provided with a resuscitation control valve I'I the purpose of which will be hereinafter described. A breathing indicator I, is positioned on the outer face of the chamber C to indicate the breathing action of the patient and the manner in whichthe machine operates as will be hereinafter described.
The usual lpressure gauge P is mounted on the body portion A to show the oxygen tank pres- A Venturi or injector tube unit V for creating negative pressure on the resuscitation cycle is mounted on the lower side of the cylinder 4 in a convenient horizontal position and is controlled by the resuscitator valve 6. A smaller Venturi tube unit V for creating negative pressure on the aspiration cycle is mounted on the cylinder 4 and controlled by the aspirator valve III.
Two-stage pressure regulator VAs shown in Figs. 1, 2 and 6, oxygen or pressure fluid from the tanks 3 passes through the usual vertical passage 23 which continues into a vertical web or partition 24 in the cylinder 4 and opens at an ofutlet 25" into the first stage chamber 2E. A separate cylinder section 21 is bolted to the rear end of the cylinder proper and provides a second stage orlo-w pressure chamber 28, there being an endwall 29 separating said rst and second stage chambers.
A cross head 39 carried by rods 3I slidable in the web or partition 24 supports a compressible disk valve 32 for controlling the outlet 25. The rods 3I arecarried by a piston 33 including an irnperforate rubber cup 34 between tWo metal disks 35. A spring-'36 between the wall 29 and the cross head 3i] tends to seat the Valve 32 whereas a stronger spring 31 between the piston and wall 38 ofthe cylinder 4 operates to hold the Valve open. The force of .these springs is such that at a predetermined pressure, say sixty pounds per square inch, the valve 32 will be closed by the action of the piston. f
i Inthe ywall 29 is an opening 39 controlled by a valve 4|! on a stern 4I slidable through said opening. ThisV stem is carried by a piston 42 1ocated in the chamber 28 and identical with pistony 33.'. -Springs 43 and 44 are so arranged in the chamber 28 and have 'such force that ata predetermined pressure, say fteen pounds, to the square inch, piston 42 will close the valve 40.
. A safety valve 45 including a copper membrane 46 which will blow at, say 100 poundsY pressure, is connected withV the first stage chamber as shown in Fig. 6. H A l Resuscitator Venturi Unit Y estense isj bolted to cylinder 4,. valvev seat 52forthe resuscitator valve `i'is provided inthe-fitting 510, said valve being of the needle type andincluding a screw threaded stem 53 operating in a screw threaded bore 53 yin said head and'tting. When valve 6 is opened, gas'will flowfrom bore'5'3' through a passage 54 into one end of a Venturi nozzle 55,v aVenturi tube 56, and a tubular hous ing 51 which telescopes the tube 56 andextends beyond the outlet end of said tube. G'as discharg-k ing into the outer end of the housing 51 from the Venturi tube 56 passes through a perforated restrictordisk 58 and thence through a tting-59 into a conduit 6I] which isl connected to a port 6I infthe Venturi unit headSI. The passage` '6IV leads into a valvechamber 62^i`n the head 5I,
said chamber having an opening-63 opening to' the second stage or low pressurechamber 28 vof the pressure regulator.
Insulator .valve The outer end of passage `V66 opens into a valve chamber 69 for the insuator Valve 8. The Valve 8 at all times closes the outer end of passage .66 and controls the insulilation operationI and the operation of the indicator as will sbe hereinafter described. The knob 1 for valve `8 is threadedly adjustable in the chamber 69 rand operates against a disk 1.0 on the valve, said disk having `4a guide pin 1I operating in a guide tube 12 Vin the knob. The screwing of .the knob in and out Will control the valve 8 and disk 1U asvvill be hereinafter described. Y
Inhalation phase of resuscitationI cycle It is now apparent that with thecontrol valves in the positions shown in Figs. 2 and 10, the resuscitator valve 6 being open and the insufllator valve 8 and aspirator valve 9 closed, the inhalator phase of the resuscitation cycle takes place. In this phase the gas at approximately fteen pounds pressure per square inch ows from the second stage chamber 28 of the pressure regulator as follows: (referring to Fig. 6) through port41, conduit 48. (refer -now to Fig. 2') valve seat 52, bore 53', passage 54, Venturi nozzle 55, Venturi tube 56, Venturi tube housing 51, restrictor disk 58, conduit 60, passage 6I valve chamber-62 in the Venturi unit head 5I, opening `65, passage 66 (re` fer now to Fig. 10), port 68,` fitting I5, and in"- side hose line I3 to mask M, the valve I1 'on the mask being then closed as shown in Fig, 11.
Diaphragm-toggle operated valvevmeans D In the valve chamber 62 as shown for example in Figs. 2 and 10, is the valve means-"Dconsistiing of a single stem 13, a valve member' v14 thereon to controlli-.he opening 63 tothe atmosphere, and a valve member 15 also on said stem to control the opening to the opening 65 which jallows gas to flow direct to the mask as aforesaid. The stem 13 is slidable through vthe Wall 68 into the chamber C Where it is connected as at y1.6 tc one end of a spring-loaded toggle lever 11 best shown 6. in Figs. 9, 1 0 and 1,1. The-toggle joint I8 isgcri nected to a postf'f!)` on a diaphragm 80 in the chamberCas best shown in Fig. 1`1. 'The toggle lever; spring 81| thereof', and diaphragm are origi-l nally installed so thatthey appear 'as shown in Fig'. 10 with the toggle joint and diaphragm extended outwardly With vthe valve stem likewise disposed 7and valve member 14 closed while valve member 1.5 is open thereby routing the gags' throughopeningv 65 and into passage v66 instead of "allowing the kgas to escape to atmosphere through the opening 63. Y
Operation of toggle-diaphragm unittocha'nge rom'z'nhalatz'o'n phase .to exhalation phase Iof Y theresu'scitatiow-cycle When the gas `supplied to the lpatient on the inhalationcyclebulds up a Vpositive pressure in the lungs of the patient and backthrough the mask openings I4 leading into the outer hose I4 as a shown in Fig, 12, and ports 83 opening* (see Figs. 2 and 10) into the chamber C, ofsay approximatelyffounounces (13 mm. of Hg) the diaphragm insaid chamber is forced inwardly and trips the toggle levery vpast center into position shown in Figs. '1 and 11. Thisshiftsthe double valveD 'so that valve member 15 thereof closes opening 65 While valve member 14 opens the openings 63 and passage 64 to the atmosphere.
Exhalatzon phase of resuscitation ce1/clev e It Vshould be noted that `the Venturi tube 56 has its exhausting orvacuum port 8'41as shown in Fig"s. 2 and 7 communicated'with a vacuum passage 482 leading through the head 5I and the end Wall 38 directly'into the diaphragm chamber C and that the evacuation action of the Venturi tube, duringk the previously described inhalation phase, is ineffectual due to the return of gas underpressure (up to four ounces) to the chamber .C through the outer hose I4, .there being if anything but a momentary circulation of pressure gas through passage 82 which becomes a part of the :pressure gas circulatingsystem until the four ounce positive pressure is reached in the chamber C and thediaphragm-toggle unit trips and moves'the valves ,14 and 15-into position shown in Figs. '1` and 11 as aforesaid.
The exhalation phase commences with this movement of the valves 14 and 15 into position shown in Figs. 7 and v11 for the Venturi tube 56 then operatesto evacuate the chamber C through passage 82, the Venturi tube 56, housing 51, c'onduit 66, passage 6I, valve chamber 62, opening 63 and passage 64 to the atmosphere. When the mask valve I1 is closed, the chamber C is communicated-With the mask, through the outer hose I4, and ports 83, and it isseen that the gassupplied to the lungs of the patient Will be evacuated 'to the atmosphere in the manner next above stated during the exhalation cycle. When, during this phase, a negative pressure of say three ounces (9.75 mrn. of Hg) in the lungs of thepatient and inthe chamber C is reached, the diaphragm 86 vrespolflds to atmospheric' pressure through port 80 open to atmosphere, and trips the toggle leverso that the valves 14 and 15 return to position shown in Figs. 2 and l0 and the inhalation phase is repeated.Vr The rate 'of operation of the "machine as a resuscitator is regulated by vturningflinch 5 '-tovarythe Aopeningof the valve 6. l
Indicator operation during rcsuscitationV Referring to Fig. 10, it is seen that the'stem 8" of valve 8 is set to vclose a port 86 leading from the passage BB into the lower end of a transparent upright indicator tube 81 vented at 81. (Fig. 10) at its upper end and disposed on the outer face `of the chamber C. On the inhalation phase of the resuscitation cycle, gas under positive pressure and which has entered chamber C from the mask M, large hose i4 and ports 83, passes from chamber Cinto the lower end ofY the tube 81 through a port 89 and encounters a light ball indicator 98 having a working i'lt in the tube, thereby elevating the `ball as shown in Fig. 10. The ball will rise in correspondence to the rate of inhalation of the patient and obviously will drop in'accordance with therate of exhalation as the pressure become negative in chamber C and tube 81. Should the ball fluctuate or flutter this is an indication of the presence of an obstruction'in the throat or pulmonary tract'of the patient or in themachine. At all events this indicator affords ari-easily and readily readable and true indication of "the manner Yin which the machine is operating per patient, and make possible ready and accurate adjustments or changes in the Voperation of the machine to best suit the particularpatient. 1
Insuaton To prepare the machine for operation as an insufflator the knob 92 for the mask valve I1 is unscrevvedlsee Fig. 13) to uncover vent ports 93 in the housing 94 'for said valve and to set the spring 95 so'that it will hold the disk valve member I1" closed over a port '96 opening into the mask until a positive pressure is reached inthe mask, below that required to shift the diaphragm 88 and toggle lever 11. If'the spring 95 will yield to allow the valve member I1' to unseat' at pressure under four ounces which is the pressure at which the diaphragm-.toggle unitinV chamber C will shift, said unit will remain in position holding valve '15 open to feed gas to the mask in a steady flow, While atmosphere vent Valve 14 remains closed. This condition Will obtain as long as the valve member l1 is adjusted'as set to operate as shown in Figs. 13 and 14 asia result of a predetermined unscrewing of the knob 925.
After adjusting knob Safor the mask valve I1 the insuiiiator valve 8 is adjusted to position shown in Fig. 13 by unscrewing the knob 1 until the disk 18 is spaced from guide tube 12 on the knob and said disk and the valve stem 8 are subject to being moved into the open position shown in Fig. 14, by the pressure of the gas being routed to the mask. The disk 10 acts as a valve for opening and closing the inner ends'of like vent passages 91 in the knob 1, which passages open to atmosphere on the side of the knob. When knob 1 is unscrewed as shown `in Fig. 13 the passages 91 are' opened by the retraction of the knob from the disk 10 and the chamber C is subject to communication with the atmosphere through a passage 98 leading into the valve chamber E9. This arrangement provides for the breathing of the patient through the vent passages 91 in a normal manner after responding to the oxygen insuiliation treatment as will be hereinafter described.
Now assuming the mask valve I1 and the insuiilator valve 8 have been adjusted as shown in Fig. 13 and the resuscitator valve 6 is properly open, it is seen that the gas under pressure passes from the regulator chamber4 28 through conduit 48,- valve seat 52, bore Q53', passage 54,- Venturi nozzle 55,- housing 51, conduit 60, passage 6, valve chamber 62 opening 65, passage 66V, port 68, inside hose lineY I3 to mask ina steady flow to the patient.y When the patient exhales, the valve member I1 opens/and, allows the exhaled gas to escapeto the atmosphere. Valve member l1 will open at a pressure less than four ounces, say 31/2, and will be opened before gas can reach the pressure in chamber C at which the diaphragm responds.A ,y y Y In this connection it should be noted that the resuscitator valve G-shouldfbe setjsothat the amount of v gas ilowing to the mask during insuillation is comparatively small and is in the most partvinhaled by the patient.- Inv other words, the lnsufflation operation shouldlbe carried out at a lower pressure than during resuscitation, due to the fact that the patient is breathing the gas during such treatment. The indicator hereof affords an accurate and ready setting ofthe valve 6 to preventwaste of gas and assures the proper insullation operation, as will now be described.
Y Indicator operation during insuiation Whenthe insuiilation operation is started the pressure ofthe gas in the passage 86 vforces the insuiilation valve stem 8 outward and opens port 86 as shown in Fig. 14, leading into the tube 81 thereby making the ballv indicator 90 responsive to the pressure of the gas. If the valve B (see Fig. l2) is set correctly the ball 90 will rise to the top of the tube,jwhile the gas is ilowing to the mask. If the ball does not rise to the top of the tube this' indicates that the valve 6 is not set correctly to 4supply the/proper amount of gas. When the patientinhales, the ballV 98 will drop since pressure lthereon is then removed. If the ball does not drop responsive to this inhalation of the gas bythe patient, this indicates that too much gas is passing to themaskand the valve 8 should be adjusted'to reduce the ow. When the patient exhales, the valve l1 on the mask opens and allows y*the patient to exhale through ports 93. At this time the ball is in down position and When'the patient ceases to exhale, the spring 95 closes valve I`1 whereupon the ball will again rise.' In other Words the ball will'respond to the breathing o'f the patient and afford an accurate indication. of the* respiratory rateV whereby the valve 6 may be opened or closed promptly and accurately to regulate the insuiation operation to best suitthe patient. After the patient has recovered and no longer requires the oxygen therapy, the valvel 6 is slowly shut off until the more or less normal breathing of the patient causes disk valve 10 to respond and allows a normalbrea'thing of atmosphere through vents 91, passage v98, chamber C and ports 83 and large -hose I4, connected between the mask and the ports 83.
Operation of machine as an aspirator The machine may be operated as an aspirator to Withdraw fluids and obstructions from a patients .lungs at any time regardless 0i Whether or not the machine is at' the same time being operated as a resuscitator or an insuffllator.
To operate the machine as an aspirator the knob 9 is operated to open the valve I as shown in Fig. 7 and gas from the rlrst stage chamber 26 of the pressure regulator will flow through a passage |08 (seeY Figs. 5, 6, and 7) into the Venturi -unit 1V' which,V discharges into thev atmosr9 Y phere. A suction portY I'Ulj (Fig. 7) leads from the venturi 'V' to an aspirator hose connection l2 on the front of'cham'b'er C as shown in Figs.
1 and 3. An aspirator hose |03 leads from con,.
necti'on' |02 to the usual aspirator nozzle and receptacle both of which are here omitted inasmuch as these elements and the manner' of their use are well known to' those skilled in the art.
' Due to the fact that the aspirator elements of the machine are independent from the other elements it is seen that the aspirator may be operated at any time whether or not the resuscitator or the insuflijator is in operation.
It is important to note that the Venturi unit V by reason of the housing 57 providing a chamber beyond the tube 56, the restriction of the now of gas from said chamber through the small orifices in the disk 58, the arrangement of the valve members 14 and I5 on ya common stem connected to the toggle lever, and the suction passage 84 being at al1 times open to the chamber C, the rate of operation of the machine as a resuscitator may be controlled with a greater mcety and the desired respiratory rate may be had at a very slow speed or speeded up as desired. It has been diilcult if not impossible to operate at a slow speed, as is often desirable, resuscitators having a venturi which discharges oxygen directly to the atmosphere from the tube itself and wherein the suction passage to the venturi is closed on the inhalation phase of the resuscitation cycle. and arrangement of the above noted parts in my machine make for a greater range of respiratory rates than heretofore, and particularly `a very slow operation for infants and premature birth cases.
Another important improvement afforded by my machine is the accurate visual indication of the operation of the machine responsive to the patient on both resuscitation and insufllation cycles. The indicator hereof in indicating the rate and extent of flow of gas into and out of the patients lungs, may be quickly and easily seen, and make possible a ready yadjustment to correct any undesirable operation of the machine.
Accuracy and reliability of performance of the machine hereof is enhanced by the use of single valve unit in which the valves 14 and 15 on a single stem having a simple connection with the spring-loaded toggle lever. Thus the entire toggle-valve-diaphragm unit is simplified and improved as to accuracy and reliability of performance by reason of the construction and arrangement thereof as here provided.
While I have shown and described a specific embodiment of my invention I do not limit myself to the exact details of construction set forth, and the invention embraces such changes, modications and equivalents of the parts and their formation and arrangement as come withinthe purview of the appended claims. f
I claim: y
l. In a machine for selectively eifecting resuscitation and insufflation, a supply of gas under pressure, means embodied in the machine for operation responsive to gas from said supply for promoting resuscitation including a mask; hose lines leading from said means to the mask, insufliation means including one of said hose lines for conducting gas from said supply to said mask; a manua11y operable valve for controlling the flow of gas from said supply to the resuscitation means and the insuillation means; valve means affording exhalation of the patient to atmosphere When The particular construction l `during resuscitation, and when in another position renders the indicator responsive to inhalation and exhalation operations during insufliation.
2. In a machine for selectively effecting resuscitation andv insuiilation, a supply of gas under pressure, means embodied in the machine for t operation responsive to gas from said supply for promoting yresuscitation including a mask and hose lines leading from said means to `the mask, insulilation means including one of said hose lines for conducting gas from said supply to said mask;
a manually operable valve for controlling the t ow of gas from said supply to the resuscitation means and the insufliation means; valve means affording exhalation of the patient to atmosphere when the machine is operated as an insufllator, an indicator including a visual'member arranged to move responsive to and in accordance with the variational pressures in the machine during resuscitation and insulation to show Vthe depth and rate of breathing of the patient, and manually adjustable valve means operatively associated with said resuscitation means, said insufflation means and said indicator and which in one position renders the indica-tor responsive to the inhalation and exhalation actions of the machine during resuscitation, and which when adjusted renders the indicator responsive to inhalation and exhalation operations during insufilation, said last named valve means being operable for opening and closing the insufilator means to atmosphere responsive to breathing of the patient should the supply of gas to the patient fail during insuillation.
3. In a machine for selectively effecting resuscitation and insulation, a supply of gas under pressure, a body structure, a hose connection on the body structure, a mask, a hose line leading from said connection to said mask, a Venturi tube on `the body structure, a gas supply passage in the body structure leading from rsaid supply to said Venturi tube, a manually operable valve controlling the flow 0f gas to said Venturi tube, a valve chamber in said body structure, a passageway for conducting gas from the" discharge end of the Venturi tube through said chamber to said hose connections, said chamber having a vent port open to the atmosphere and a pressure port opening into that part of said passageway leading to said hose connection, a diaphragm chamber in said body structure, another 'passage leading from said Venturi tube into said diaphragm chamber for creating a sub-atmospheric pressure therein, another hose connection on the body structure opening into said diaphragm chamber, a hose betweenl the second named hose connection and said mask, a valve stem in said valve chamber, valve members on said stem arranged so that in one position of the stem one of the valve members opens said pressure port andthe other closes said atmosphere vent port and in another position the vent port is opened and the pressure port is closed, a springy loaded V11 toggle in said diaphragm chamber connected to said valve stem, a diaphragm in the' chamber therefor connected to said toggle and being responsive to predetermined positive and negative pressures therein, an exhalation port through Which the patient exhales to the atmosphere the gas supplied to the patient during operation of the machine as an insuiiiator, a valve means manually adjustable for closing said exhalation port during a resuscitation operation of the machine and manually adjustable for opening responsive to a positive pressure developed in the mask below the pressure required to operate the diaphragm and said toggle, a transparent upright indicatorftube, a passage connecting the lower end of said tube with said diaphragm chamber to create positive and negative pressures therein 12 responsive to the inhalatory and eXhalatory phases of operation of the machine as a resuscitator, and a visual indicator member mounted in said tube to rise and fall responsive to the positive and negative pressures created as aforesaid to indicate the rate and depth of breathing of the patient; another passage leading from said passageway into the lower end of said indicator tube, a valve manually movable from a position closing the second named passage to said tube to a position opening said second named passage to cause the indicator member to respond to pressure changes during insuiation whereby the indicator will move in correspondence to the breathing of the patient on insuiation as well and during resuscitation operations.
LE ROY G. FOX.