US2054850A - Gas pressure regulating and signaling means - Google Patents

Description

Sept. 22, 1936.

GAS PRESSURE REGULATING AND SIGNALING MEANS G. M. DEMING Filed April 2'7, 1955 2 Sheets-Sheet 2 :E zg. 3.

INVENTOR Patented Sept. 22,- 1936 25054350 7 GAS-PRESSURE REGULATING AND T SIGNALING MEANS I George M. ,Demi ng East ,Orange, N. J., .assignor .to Air Reduction Company,- Incorporated; New York, N. Y. acorporation of New York mplication Ama a, 1935, Serial No.18',67.0

.11 Claims.

-Thisinvention 'relates to low-pressure signaling means, andmoreespecially-to pressure regulating r and signaling =means. For ex'ample, -in a system tor supplying-gas at regul'ated pressure or flow, tfhe gas beingderived from-a sourceof compressed "gassubject *to ex haustiomfiit may: be desired to '*give'-'-forewarning of 1 approaching exhaustion of the source. In this connection one purpose for which the in vention may' be -app1ied is :to give a nurse 017 other attendant-adequate and depend- "-able warning that an oxygen cylinder' from which ox-ygen is' being' administered toia patient' should be-replaced with-a'-full =oylinder, or that the -=valve cf a reserve c-ylinder already connected with the "apparatus should be :open-ed.

For this -purpose it was recognized that if the signaling device was not' so thoroughly depend- *able thatits =proper=peifformance could be considere'dassi1red, the very presence of the device would invdlve' the danger of oxygen depletion to "the patient; because a moderately high degree :of dependability mightencourage the nurselto rely entii-ely-on' the signal. A'fter serious 'considerationof various electri- 'cally operated signals; it was decided that none o'f these would be suitable for use in oxygen therapy; for'the-"following reasons: 'bell or buzzer 1 is 'not -mechanically' --dependable enough. Any lamp or visible signal *is -Eobjectionable in that a ai-is'lble s'ignallfis not so likely to arrest 'the attention 'of' the attendantas is an audible signal. Electrical contact-sandcircuits arenot suifi ciently immun'e to-open circuit troubles. No commercial -li'ghting circu'it, or even a battery, can-be viewed-as :35 ea suilicientlyidependable source of voltage. Any electrical connections, such 'as wires, extending from the regiilator to the wall of the room=would be objectionable. "The possibility-0f a signaling device actuated "by clockwork was also discarded #0 --"beoause,;even if it could be *made suflicieritl-yde- "eperidablemechanically; it 'wouldbe" too much depen'dent' upon the human element.

From the-study which resulted in the developx-m'ent'o'fthe-signaling cleviceherein disclosed it was c0ncluded that the signall should be an audi- *wasrequired-be'fore the "most satisfactory solution of the problem'was reached. A-whistle,for-'e-x- --ample,- could-be used;-but vvould use considerably more'oxygen' than would be fdesirable if the signal were-to be sufiici'ently audible. -It=was finally '-*fcund that a simplereed-ins'trument, for example device for determining when the signal shall sound, thesignaling- 'means should preferably embody -a '-pitch--pipe' or some =o'ther simpleumd 'dependable windinstrument which will operate satisfactorily upon *feeblegas"'flows :and be loud enough to be heard clearly throughout a large ward.

further lobjec't of the invention isito provide a signal which will sound =over a substantial :pe- =riod,-;preferab1yef the order of five or iten: minutes,- before the cylinderiis exhausted, -ratherfithan "sounding only'brieflypr but once. a

'If after the starting o'f the signal, the pressure in the region from which gas-is allowed toescape through the signal is continually declining, as is the "ease in "the embodiment -of the invention herein illustrated, it is important to provide means for maintaining the lou'dness of the :sig- *nal', so that it does not=quiclz ly die away, :or for even causing it to increase. This'is accomplished by *the provision o'f an automaticwolume :control valve in series with-a pressure-responsive signal --controlvalve. I f i r "I'he"introductiomdflthe volumecontrol valve created a problem since it was foundthat the relationships involved between the volume con- "trol "valve and the reed instrument were complex.

It was discovered, however, that necessity for undue exactitude in design and manufacturecould be obviated, anda clearly audible' signal sound could be insured; by interposing between the :reed instrument ami' the "valve mechanism a chamber of relatively large volume.

In' a more general '-*aspect, the invention embraces -a gasmupplysystem for supplying gasat uniform reduced-pressure, -orat uniform fiow,

-and*for "announcing beforehand depletion of" the "source of supply. The -c'omplete combinationineludes two stages 'of pressure regulation, or two 5 pressure regulators, of which the firs't' is o'ne havgi ngadecliningpressure regulation characteristic.

"In such-application of this invention the signal- *ing" device isconnectedwith an inter-stageregion,

inother words,-a region sub'jectto the regulation '50 of thefirst-stageregulaitoi. Withregulatorshaving a declining pressure regulation characteristic the' delivery pressure declinesgradually while the cylinder pressure falls at a mu'chgreater rate As the -'deli-ver-y pressure ='of a regulator varies mm ing of the signal, the signal being brought into action at a point of steep decline in the regula--' tion curve of the first-stage regulator, this occurring a few to several minutes before the secondstage regulator ceases to function as a. means for insuring maintenance of proper delivery pressure or delivery volume; r

The specific and most advantageous embodi-' ment of the invention is one in which the signal and a compound or two-stage regulator are combined in one instrument.

Whether the signal is applied to a two-stage or -to a single-stage regulator, other objects of the invention are to make the signaling part of the apparatus compact and small in relation to the pressure regulator, to provide a signaling device which can be applied to the regulator with mini- .mummodification of the most effective and economical construction of the latter, so that an approved, standard regulator may be employed,

and to keep the manufacturing expense of the signaling part of the apparatus as low as possible.

In the accompanying drawings, forming part hereof:

Fig. 1 is an elevation showing apressure regulator equipped with a signal in accordance with the invention, the regulator also carrying a pressure gauge, a float gauge and. a wash bottle and being connected with a gas cylinder, the gas cylinder and the wash bottle being shown in a fragmentary manner;

Fig.2 is a vertical section taken in a substantiallyaxial plane through the regulator, the signal and a portion of the float-gauge column appearing in elevation; and r 7 Fig. 3 is a section taken on the approximate line 3-3 of Fig. 2.

The regulator proper 2 which has been selected forillustration is substantially like the compound gas pressure regulator disclosed in my Patent No. 1,948,027, dated February 20, 1934, to which reference may be had. 7

In Fig. 1 the regulator is shown mounted on a compressed gas cylinder 3, with the valved outlet of which it is connected by an inlet nipple 4 and nut 5. The regulator bears a high pressure gauge 6, and at the side remote from the inlet connection it has a boss or receptacle 1 which holds .a vertically rising float-gauge column 8 and a downwardly directed outlet 9 by which the gas delivered from. the regulator, after passing throughthe float-gauge, may be delivered into a Wash-bottle ID, from which it may be taken off through a flexible tube H. In the use of oxygen for medical purposes the fioat-gaugeshows reliwherever it may be useful.

circumferential wall of the body I5 of the regulator, between the pressure gauge 6 and the float-gauge 8, hence a requirement for compactness in the construction of this device.

The regulator body I5 is preferably of circular cross-section, with suitable external bosses. The body has an internal wall [6 at opposite sides of which are cavities I] and I8 closed by diaphragms l9 and 20, which are clamped to the body by a back cap 2| and by a bonnet 22, into which latter In passing from the cavity IT to the cavity la the pressure is reduced again, and for medical purposes is held at a low value in cavity l8. The region I8, may, therefore, be referred to as the second-stage or low-pressure cavity.

The regulator illustratedconsists in effect of two regulators in series built in one unit, but in the broader purview of the invention individual regulators may be employedand the signaling device may be connected at any point of the system between the regulators, and it may also be used with but arsingle stage of regulation, or

The signaling deviceis most serviceable when connected with an inter-stage region between a direct-type regulator acting as the first stage and another regulator, preferably of the inverse type, acting as the second stage A direct-type pressure regulator may be defined as one in which the thrust of the high pressure gas seeking to pass the regulating orifice of, the regulator tends to open the valve of this orifice, whereas 7 and inverse second-stage regulation can be made to give remarkably even ultimate regulation, and the steeply descending portion of the regulation curve of the first stage beyond the end point of regulation of that stage can be utilized to start and keep the signal sounding while the secondstage regulator is still effective.

In the'regulator of the drawings the high pressure gas finds its way; from the inlet connection 4 through a passage 24 in the regulator body to a nozzle 25, the bore of which is the regulating orifice" of the first stage of the regulator. The gas in this orifice thrusts against a seat or valve element 26, disposed in one end of a lever of the first class 21, the thrust of the gas on the valve element being opposed by a compensating spring 28. The other end of the lever 21: bears against the inner side of the first-stage diaphragm I 9,

the positions of thisdiaphragm, and consequently the positions of the valve element 26 with respect to the lip of the nozzle 25, being responsive to slight variations in gas pressure inrthe interstage cavity I1, this gas pressure being balanced by the thrust of a regulating spring 29 against the outer side of the diaphragm, this spring being retained by the back cap 2l. When the regulator is in operation, gas passes from the cavity I! to the cavity l8 by way of a second-stage regulating orifice 30, the inlet of which is commanded by a valve element 3|, this orifice-1 30 by -thepressure' of gtheT gas; seeking vreawh:theorifice andwalsoJo aam n ii flla prmg v l elemene-be aursc t war tml oz trthe 3a.;- A-i thrust-i e em n 3-; ,cexte dins; rom the valve element 3] through the, orifice 30-; ,hears against-i the, 1 insideoft; the second-stage diaphragm; 20, the movements lot which and ot the valve-element 3| are responsive-to any va-riations int-pressure in-the low-pressure cavity, l8,- this gas pressure being;.o.pposed :by; the regulating and adjusting sprinafifi in-(thebonnet 22,: By; turn:

ting -therscrew l 2- zthe stress of the; spring 34,. can

be'adjnsted, and-- thereby the pressure ofthe gas in the cavity i8 and-the rate ofudelivery of; gas can, be regulated, The outgoing gas flows ,from

the cavity l8 through; ai-passager-35 into the in:-

terioryoithe boss 1; whence py suitablei passages (not; shown) it :isconducted throughathe; floatgauge and eventual-ly downward to, the outlet; 9'. The sighal-ingdevice-J l is-;conne,cted;with the inter-stage cavity .orcregion -I 'l.- For ,this. purpose a. passage 36 is made ;-inthe bounding wall of theregulaton body-to, serve as an; adm issio n, port for; the signaling;device the inlet end-of this admission portopening into .thersaid- :cavity H,

The casing-of the signaling; device is applied to the regulator ovenand; around; the outerend "oftthe port 3.6...-, Thisecasing may be made in variouslways but as shown it. vis i comppsed-of three pieces 38,. ,39'and .40. Agasket 4 Ms placed betweenathe; piece 38, and, the outside; of the regulator body, and the piece 38: rnay'be secured tothe body, and the. pieces ,33 and 39}.may; be? secured together by screws one vofwhich is shown at 42. A diaphragmt43, exposed -togthe gaspressure; in a chamber 7-44 finsidethe piece: 38,

.isclamped. atits margin-between theparts 38 and '39, and carries. at its outer side avalveele- .rnent 45, this valve element-being heldin a .hold er 46,,which is tightly clamped to vtheecenter of the diaphragm by'scremmeans 41., The: valve element.45co-nstitutes,the, part of asignal control valve whiclrcoactswith the lip of a signal control orifice. 48; A. signals-c ntr l sp in 49,

confined between the part 39,:ancl the outer side 01"; the signal; control-i diaphragm 43, tends to unseat the valve element. 45,- but; the; stress of this-Lspring and the effective: area. of; thediaphragm 43 are so related that the pressureof thelgasagainst the diaphragmllkeepsthe valve element tightly closed iagainst the orifice 48;vv until. thep'ressure. in the regulator; cavity, H. declinestoa substantially-low:value. r

Gas. finds its; way from-the chamber :44rtoz-thfi H signalcontrollorifice 48by way-of a volumemcntrolvalve comprising a volume-oontrolorifice15,0

and. volume-control valve element 5l-.- A. passageway 51:1:1'911117116 chamber, 44;.to1the volume- 7 [control orifice, iifiis formed in the piece 38,.and

extends Jthroughthemarginal portion of thediaphragm 43. Volume-control orifice {this an ac curately formed tapering throat formed in an element 53 inserted in:the piece-39t Thevolumecontrol valve elementpreferably;consists, of an accurately dimensioned head on a ping54-iwhich istguided-ti n the fDiQCQ3i9e'f In the operation of the device the volumecontrol valve element 5| moves slightly within the tapered throat 50. The thrust of the gas seeking to pass the valve element 5| and to escape through the restricted throat or orifice 5!] urges the valve element toward the narrow end of the throat, but this movement is resisted by the volume-control spring 55, which is confined between a collar 56 on the valve stem 54 e d-Jar. bu ment: n e: he piece- 39- Aiter leavin the,- volume control orifice 5l1.;thegas fl ws-5 hvmnc r arae pass s 5 584. he Piece a t e a v l a e v s naln nt cl ow-8;.

When the control valve element 45 is-unseated from the; sig al'control; orifice 48, the gas enters a space 59 in the 'piece 3c9,- which space a is in free i v. 1;; hamb oidareecan c ty 6,9,: inside the. shellrlilge piece 40.- This may v be termed a s nance hamb r: iece may be secured t he p c 3 in-s r ws the-J ints between tl iepartsbeing made tight by a gasket 62.

The 313458 0i; a sounding element 63 is secured inamopeningin the shell '40! Forreasonswhioh have been i n a s rum nt as s e ia advantages 'ior the purpose of the invention. That illustrated is in the natureoi the familiar pitch pipeits reed being designated 64. I

Incompleting the description of the operation oi the invention itwill not be necessary to re;-

view the operation of the regulator proper. When,- as the result of approaching exhaustion of; the cylinder or source -3-, the pressure in the inter-stage cavity ll of theregulator'has declined to a relatively low value, whioh is preferably-hear or somewhat I below the svalue correspondin to the endzp oint of regulation of the first stage of theregulato-r; the lowering pressure beneathathe signal; control-diaphragm 43 permits the signalr control; spring-=- l9e to unseat the signal control valve element 45 frorn the signal control orifice 68,, lvlerelyifor-purpose of illustration it maybe stated thatin the apparatus 1 shown inthe draw,-

:Zngs-the, relations aregsuch that the-signal control 1 is: het lmmediate v aiter v h s gna ontr {Valve is opened the volume control valve element 5| will; be -driven toward thenarrow end; of the th at or fice mpr ssin th -wwm -whrcle-snr ns fifiitw lha occupy c os t that the clearance between the volume-control alv el ent andthe thr at o the ume-99 trc r fi i ve 3 1 i h is a -1dr;

ion bt ning, thedis -s of oxvsen throuch the alum e n r lva v nd m tel ro eh he d nstr ment. ugh; sma wi l e f cie-n-t to-cause the reed I t tosound a plainly audible note.- Wt I es u e i t e n e ta avitr he/resa etor,- thedifferential pressure across the volume ntrol-mir el ment w lle du l y im shconsesv nt vth lum nt lc pr n 55: w l

hat he H a 4 1y decreasing restriction in such manner as to compensate for the decreasing gas pressure, so that the rate of delivery to the reed instrument may be maintained fairly constant; or if the volume control valve is proportioned suitably, the rate of delivery to the reed instrument may actually increase while the gas pressure acting on the volume control valve is decreasing. The resessively, falling onance chamber 69 has an important effect in producing a strong signal on a small flow of gas and obviates much difficulty that would otherwise be encountered in securing proper cooperation between the reed instrument and the volume control valve.

Another feature of the invention which has not previously been mentioned is that assurance that the signal device is in working condition is obtained whenever the regulator is placed in operation, for when the cylinder 3 is opened a brief signal will be heard during the flooding of the interstage chamber i"! of the regulator to its normal pressure level. This sounding of the signal when the cylinder is first opened serves as a check that can not be omitted even if the attendant should not be inclined to go to any particular pains to be assured that the signal device is in working order. Aside from this, however, the signal is highly dependable, its parts being few and of such character that they are not subject to derangement.

I claim:

1. In a gas supply system, the combination with pressure regulating devices for regulating in a plurality of stages the pressure of gas derived from a source, of an audible signal connected with an inter-stage region of said system, said signal being actuated by gas escaping from said region after a decline of inter-stage pressure.

2. In a gas supply system, the combination with pressure regulating devices for regulating in a plurality of stages the pressure'of gas derived from a source, of means for setting up and maintaining an audible signal actuated by gas escaping from an inter-stage region of said system.

3. In a gas supply system, the combination with two pressure-regulating devices to regulate the pressure in stages, the first of these devices having a declining pressure-regulation characteristic, of an audible signal connected between said devices and actuated by the gas and having a valve which opens when declining inter-stage pressure is still above the end-point of regulation of the second stage.

4. In a gas supply system having successive stages of pressure regulation,- an inter-stage, audible signal energized by escaping gas, said signal having a signal control valve responsive to a decline of inter-stage pressure, and an automatic volume-control valve in series with said signal control valve so that the amount of gas reaching the signal is restrained by said volume-control valve.

5. A compound pressure regulator having a first stage of the direct regulator type and a second stage of the inverse regulator type, an interstage region between said first and second stage, a reed instrument connected with the inter-stage region of said regulator, and means responsive to a predetermined decline in inter-stage pressure for causing gas to escape through said instrument.

6. A compound pressure regulator having a first stage of the direct regulator type and a second stage of the inverse regulator type, an interstage region between said first and second stage, a reed instrument connected with the inter-stage region of said regulator, a signal control valve with pressure-responsive means responsive to a predetermined decline in inter-stage pressure, and an automaticvolume-control valve in series with said signal control valve for determining the rate of flow of gas to said instrument.

7. A compound pressure regulator having a first stage of the direct regulator type and asecond stage of the inverse regulator type, an inter-stage region between said first and second stage, a reed instrument connected with the inter-stage region of saidregulator, a signal control valve with pressure responsive means responsive to a predetermined decline in inter-stage pressure, an automatic volume-control valve in series with said signal control valve so that gas flowing to said instrument passes through both valves, and a resonance chamber preceding said reed instrument.

8. A gas pressure regulator with means for signaling approaching exhaustion of the gas supply, said regulator having a body and pressure regulating means of the diaphragm type, said body 7 having a' port through its wall communicating with a reduced pressure space of the regulator,

and said signaling means being applied to said body outside said port and comprising a reed instrument and automatic valve means controlling escape of gas to sound said instrument.

9. A gas pressure regulator having a body and pressure regulating means of the diaphragm type, and a device mounted on said body for signaling approaching exhaustion of the gas supply, said device comprising a reed instrument, together with automatic valve means controlling escape of gas froma reduced pressure space of the regulator to said instrument.

10. Low-pressure signaling means comprising, a reed instrument, a signal control valve, pressure responsive means for causing said signal control valve to open and pass gas to said instrument at a predetermined point of decline of pressure in a region with which the signaling means is connected, and a volume-control valve in series with said signal control valve so that gas flowing to said instrument passes through both valves, said volume-control valve comprising a tapered throat, a valve element moving within said throat, and a spring resisting the movement of said valve element in the direction of decreasing throat diameters;

11. Low-pressure signaling means comprising,'

tapered throat, a valve element moving within said throat, and a spring resisting the movement of said valve element in the direction of decreasing throat diameters, and a resonance chamber interposed between the valve means and the reed instrument.

GEORGE M. DEMING.

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