US2561264A

US2561264A - Gasifying oil burner for heating purposes

Info

Publication number: US2561264A
Application number: US744972A
Authority: US
Inventors: George M Burgess
Original assignee: Individual
Current assignee: Individual
Priority date: 1947-04-30
Filing date: 1947-04-30
Publication date: 1951-07-17
Anticipated expiration: 1968-07-17

Description

July 17, 1951 ca. M. BURGESS 2,561,264

GASIFYING OIL BURNER FOR HEATING PURPOSES Filed April 30, 1947 3 Sheets-Sheet l ml Li if JMR A July 17, 1951 G- M. BURGESS 2,561,254

GASIFYING OIL BURNER FOR HEATING PURPOSES Filed April 30, 1947 3 Sheets-Sheet 2 Y V /A I i i 1 I 1 I l l I IN V EN TOR. 7/f V 0 LF 62-0,? 6: #2 50965; 4 U

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y 17, 1951 s. M. BURGESS 2,561,264

GASIFYING OIL BURNER FOR HEATING PURPOSES Filed April 30, 1947 3 SheetsSheet 5 INVENTOR. 6 50/96 Mfiueass;

Patented July 17, 1951 UNITED smress ea -TENT GeorgeMBurge'ss, La Fayette; 1nd?- 1 AppiicationApri-l-M, 1.947, Serial:Nor744;97.-2

10 o1ai'ms:'- (Cl. iss sw This invention -relates to an-oil 5 burner, of i general use-tor 'heating -purposes" andespecially adapted for use in heatingiur-naces',andto auto matic control thereof.

It is the object of my invention tdprovide 'an -5 oil c burning devicefor "heatingpurposesi'which' I will be reliab1e;-safe a-nd eificient; which'will be" adaptable touse in various installations, and is specially suitablefor use in domestic furnaces; andwhich will provide desirable and adequate: "'10 automatic controls to regulate the operationf the device underthe-various conditions of 015- I. erati'on lt isa special object of my inve'nt'ion to 1 p-rovicle a simple and practi-cal device whichv will i efieot----thorougligasification -of fuel onsho to 1 its-admixture:with -air for combustion, will' the'n combine-the :gasified fueloil with air in an 'efficient-combustible: mixture in asystem' that lends-itself r to automaticcontrol andto autornatic ignitionyto provide a reliable and-rapid starting operation insuch-a device; to provide simple and-reliable controls in combination-with such systemgto provide in.the-starting and controls a progressive operation, such fonexamplei that interruption of the starting-cycle at any point willautomatically-prevent initiation of subsequent operations in such cycle; and-to combine-the accomplishment of suchseveral objects in a combinationinstallation unit, whichunit will have "a minimum-of operating parts andno 3O mechanically operating parts subjected-to high temperature,:which- Willbe convenient, practical; I and -"-inexpensive: 'to manufacture, which will readily lend itselfto'application' in a wide variety of installations, will require a minimum Of" serv J icing in such installationsand will be convenient for 'any: :su'ch servicing that may be required.

In accordance with my invention -combustion v is causedto'take'r place in part of a 'firin'g cham ber which is conveniently-tubular in form andwhich'l maycall a-:firing tube=. The incomin fuel-' -oil is fed underloW=pressure=-to gasif-ying chamber positioned-to receive heat for effectiveand self sustain-in'g oil 'gasification from combustion in the firing chamber, desirably through a Wall thereof. The gasified oil is discharged into the-tube; through ports which'impose little or no back p-ress'ureand open from the peripher'y of the-' tube; and the gasified oil is' mixed-with air' fed -axially through the -tube; into "an -efficient combustible mixture; An independent source-of initial gasifying heatto.the..gasifyingchamber-is provided for starting; I

Desirably', the =gasiiying :chamber is maintained emptyfiorsubstantially empty under sta'ndby initially-admitted thereto 'at the" contioll lar; surrounding thefiring'tube, *and 'h'as ai gas ,ing chamber: at initial gasity-ingtemperatureg as" operation oil sdppned theretdfor' heatin'gooer tion== is admitted under I 1ow p're'ssiire at a" con" trolled rate -and the "gasifyi'ng chamberpresehts a surface at a temperature to gas'ifV the pfl rate This provides an immediate initial supmyrar "g'as fied oil to start combustiorifwhili progressivel" provides additional heat to 'progressively' iaslf' theprogressi-vely incoming supplylofoil nd t progressive action quickly establis elf s'ii porting gasification and' c'ombust'io'ri at conitinuous-oper ation rate.

In -the:--- selfsiistainedj full" operation whic ensuesthefiring" tube wall of 'th asifyi chamber is maint'ain'ed'at ahighfitemperature for example-eat redheat, to efie'ctiv'ely'gasify' the" oil for highly efiici'ent combustion;

Heating meansforthe ihitial'ga fyirig'surfa'ce. and primary ignitionmeahsfmavbe for any of several types, electric, gas; "or oil"ope'rated1" I prefento employ a continuoiisly operatin'g "he ing mea'ns, witheither gas or oil as its fuel, an to use a pilot' fiame from" thssamesource rm ignition "in thestarting cyclei Change from full" operation to stand by oper' ation andvice versamay be efiectedby a simpl shut-on valve in theinco'ming "oil line;'and ahy1 desired-changein airsupplvbetweeri 'stan'd' and full operation is preferably under a" control responsive to a conditio'ii' of 'establishedfdom bustion, forjexample th'e'tempe'rature thereo Desirablyf'the gasif'yi'n'g" chafnbef'has its*o1 inletat ornear its bottom and its gasroutlet at" or near'the top, and the oil supp'ly is controlled at'-'" a constantlevel- -between" such" inlet ando'utl'et.'

In "a preferred form of myinventior'i," thefToil flow, under constant level control 'and low head leads-through the-shut-ofl v'aivezand a'mete'r'ing, valve to a gas'ifying chamber 'inlet'positiorie'd jacent theflame-discharigeend of me ering-awe and a short distance b'elow"the""oi-l 'level of con stant' control? The gasifying chamber is" anriu outlet a't'the top; above the constant oil-"leve to a manifold which also receives*heat frorfi the firing tribe 5 andwhich distributes th h'Ot' gasified oil "to fuel po'rts in the wall :of *the firing tub During starid b3 -=*operation;independent heat ingmea'ns maintainsa lo wer ipart-bfthe g-asity by a"continuously-burninghas-or oil flame, and; such heating means: may also provide -a pilotflame;- :Preferably, ,theindependent heaten is positioned outside ther combustion -tube=and hea a portion-of the outer'wall of -the gasifying chain- 3 her, so that its operation is substantially independent of conditions within the firing tube, and where it may be independently housed for controlled reliable operation.

The oil control valve is desirably one whose normal position is closed, and which during demand for heat of full operation is opened and held open by electrical means. Air for stand-by operation and for initial combustion in the starting cycle is desirably supplied by natural draft. When initial combustion is established, an additional supply of air is provided by a blower, controlled in response to the temperature in the firing tube, and desirably operated from the same electrical source as the oil control valve.

My oil burner is of relatively simple construction, and its controls and many of its parts may be of standard form and operation. Preferably, its firing tube assembly is of cylindrical tubular stock, but it may be of other form and material. The firing tube assembly may be, and desirably is, .a self contained unit which may be made in various sizes and forms for selective combination with an operating unit to meet the requirements of a particular installation. It may be mounted in any desired position, to discharge horizontally, vertically, or at some intermediate angle.

My burner is readily adaptable to the usual thermostatic control, for its whole operation may be, and normally is, controlled by the single shutofi valve in the oil supply line, which may be made responsive to the usual room thermostat, or to the combined control of a room thermosta't and a limit control, or to other desired or usual control devices.

The accompanying drawings illustrate my invention. In such drawings, Fig. 1 is a plan of an oil burner unit embodying my invention; Fig. 2 is a side elevation of the unit shown in Fig. 1,

with the firing tube assembly shown in section;

Fig. 3 is an elevation, taken from the opposite side of Fig. 1, and showing details of the blower inlet; Fig. '4 is a vertical section taken at the flame-discharge end of the firing tube, on the line 4-4 of Fig. 2; Fig. 5 is a fragmental horizontal section on the line 55 of Fig. 4, showing details of the. gas burner used in this modification as the independent source of heat for the gasifying chamber; Fig. 6 is a vertical longitudinal section of a modified form of firing tube assembly interchangeable with that shown in Figs. 1 to 4., and in which the firing tube discharges vertically against a bafiie; Fig. 7 is a vertical longitudinal section of another modification of a firing tube assembly, also interchangeable with that of Figs. 1 to 4; and Fig. 8 is a horizontal section taken on th'e'line 88 of Fig. 7.

The oil burner shown in Figs. 1 to 5 comprises a firing tube assembly A, shown in section in Fig. 2, .and an operating as esmbly, embodying fuel and air supply and control devices mounted on a common base 13, and providing an upright wall by site end is open to the discharge of a blower l2 driven by a motor i3 (e. g. of horsepower) and having' an intake M controlled by adjustable vanes I5. Desirably, such inlet is below the outlet into the firing tube I U, to promote natural draft therethrough for the starting cycle.

The firing tube H] is surrounded by a tube 2!], spaced from the firing tube H3. The space between the two tubes in and 2G is sealed at the front and rear ends of the tube 20, as by rings 22 and 2t welded to the two tubes. The two tubes It and 20 are also joined over most of their circumference by a dividing part-ring 25 welded to the tube It before assembly and welded to the outer tube 29 through a slot which overlies the part-ring 25. The part-ring 25, divides the space between the two tubes I0 and 20 into a gasifying chamber 2| and a manifold 27, and leaves a gas outlet 26 at the top of the gasifying chamber 2| leading to the manifold 21. Such manifold 21 communicates with the interior of the tube In through a circumferentially spaced series of fuel ports 30 in the firing tube wall. An oil supply pipe 3| extends forwardly beneath the gasifying chamber and opens into such gasifying chamber 2i at its bottom, and desirably at a point near the front of the firing tube I6. I

For starting, the gasifying chamber 2| is sup plied with a source of heat independent of combustion in the firing tube Ill. Such independent source of heat may be an oil burning device, or may take various other forms, as indicated above. As shown, the independent source of heat is a gas burner 48 positioned beneath the gasifying chamber 2 I, and provided with a series of burner ports beneath a bottom portion of the outer wall 20 of the gasifying chamber 2|. In addition, the gas line extends forward to the end of the firing tube ill, and is there provided with a burner port 4! to provide a flame for ignition. During standby operation, this gas burner ii] heats the bottom portion of the gasifying chamber to initial gasifying temperature and the gas burner 4| provides a pilot flame, to maintain the installation ready to meet any demand for heat. Gas is supplied to the burners 59 and ll through a supply pipe 43, which may be connected to a source of supply through a pressure regulator 42.

The wall of the firing tube It extends rearwardly to a mounting plate 46 and is welded thereto. The wall 253 of the gasifying chamber 2| is desirably terminated immediately behind the manifold 2'1, and at this point there is a dividing wall 4? through which the firing tube passes. The walls '46 and 47 extend downward below the firing tube, where they are interconnected by a tube through which the gas burner ii) extends and which is sufi'iciently larger than such gas burner to to provide a passage for secondary air to that burner. The oil supply pipe 3! also passes through the two

walls

46 and 41 and is desirably tack welded thereto.

An outer cover wall 48 for the firing tube assembly extends from the rear mounting wall 45 forward to the end of the outer wall 2f] of the gasifying chamber, and is supported thereby and by the walls (it and 41. The space between the walls 46 and ii and enclosed by the casing Wall 4-8 is desirably packed with insulating material.

The casing wall 48 forms an enclosure for the firing tube assembly and the gas burner and oil oil pipe, which are located below it, to facilitate control of the gas burner and retain its heat. The forward end of the assembly is desirably closed by a cap 49 which may have an in-turned flange alined with the firing tube wall 19, in which case such flange is suitably cut away at the bottom to pass the pilot flame from the burner 4i and to provide an outlet from within flowing through them from the gasifylng chamber under normal conditions, which prevents any pressure in that chamber from blowing back through the oil line 3|. Moreover, the arrangement is self regulating, for if gasification should proceed at too high a rate and cause a rise .of pressure in the gasifying chamber, any such pressure would be backed up only by the low headordinarily not more than about'an inchof oil in the line from the constant level control, so that such back pressure would diminish the flow of oil, and hence reduce the rate of gas generation, which would promptly reduce the excess pressure.

When the call for heat is satisfied, the oil shut-v off valve 36 will be closed, and the supply of oil to the gasifying chamber 2i will be cut off.. But gasification of any oil in the gasifying chamber will continue, and its combustion will continue, and theblower will continue to operate, until the residual supply of fuel is exhausted. When this occurs, and the firing tube assembly cools to a sufficient point, the thermostatic element Sill will operate the relay 5| to stop the motor E3 of the blower. Q j

' Regulation of the oil burner to meet the differing heat requirements of a considerable range of difierent installations is readily accomplished by regulation of the metering valve 37 in the, oil supply line and by regulation of the vanes H3 at the entrance to the blower. Such regulation" is facilitated by the fact that the oil is fed by gravity, under a low pressure head and under a constant level of control close to the bottom of the gasifying chamber 2!.

The method of operation and of control in my oil burner provides reliable operation, and the parts are so related as to insure safety. If for any reason the electric power should fail, during full operation the shut-off valve 36 would simply close and combustion would soon terminate for Lacking the independent source of heat, no gasification would occur and the oil would remain liquid and confined in the gasifying .chamber below the constant level of control. -If, after initial combustion had been established in the firing tube H], the thermostat 50 or the relay 5| should fail to start the blower motor l3, com- .bustion would nevertheless proceed with air under natural draft, and although in such case combustion would be inefiicie'nt, it would be fully self sustaining. If the oil supply should fail, the unit would simply remain, or. return to, stand-by operation; while if the oil shut-off valve should fail to be closed fully, or to open fully, the unit would merely continue under or tosustained operation at a reduced rate of consumption, with or without forced draft depending upon whether the temperature of operation was suffi- ,cient to cause the thermostat 50 to effect operation of the blower.

.' a In the modification shown in Fig. 6, the gasifying chamber construction is the same as that shown in Figs. 1 to 4, but the firing tube is provided with an upturned elbow 10 so that its flame discharge end H is directed vertically upward. In such case, a flame deflector 12 is supported co-axially above the flame discharge end ll ofthe firing tube, conveniently by a post 13 supported in a holder in the elbow 10 and by spider arms M at the upper end H of the elbow 1D. In this modification, the lower part of the gasifying chamber 2i is heated by gas emerging from burn-- or ports 40, and the burner pipe is continued forward and upward to provide a pilot burner 4| just above the flame discharge end "ll of the firingtube.

'ried by a mounting plate identical with the mounting plate 46 shown in Fig. 2, so that it will be interchangeable with the firing tube assembly of Fig. 2 in combination with the operating assembly carried by the base B.

outer wall of the vertical portion 82 forms the inner wall of a gasifying chamber 83 formed betweensuch wall'and an outer wall 84, and closed at the bottom and top by rings'85 and 86.

An oil inlet pipe 88 is connected to, the gasifylng ,chamber 83 through its outer wall 84 and near the bottom of the chamber. The gas outlet from the chamber 83 is into the upper end 89 of a channel 92! running downward along, and welded to; the wall 82 of the firing chamber. Such channel forms a passage leading from the upper part of the gasifying' chamber 83downward and around theelbow 8| to a manifold 9i encircling thefiring'tube at the lower end of the elbow 8|. From the manifold 91, gasified fuel is discharged in the firing tube through ports 92.

To maintain the assembly in stand-by condition ready for automatic starting, the lower end of the gasifying chamber 83 is heated. For this purpose, a gas line 95 runs along below the horizontal section 8!! of the firing tube and upwardly to a. burner ring 96 encircling the upper end of the elbow 8| just below the bottom ring of the gasifying chamber. A continuation 91 of this gas line extends from the burner ring 96 upward to a point above the top of the firing tube 82 to provide a pilot burner 98.

As in the modification of Fig. 6, this vertical.- flameburner is provided with aflame deflector 72, supported on a post 13 coaxial with the vertical portion 82 of the firing tube. Such post may be supported at the bottom by a socket I80 mount- .ed on the inner wall ofthe elbow 8|, and by spider arms ,IDI engaging the sides .of the vertical portion 82.

i This modified firing tube assembly may be carried' by a mounting ,plate identical with the mounting plate 45 shown in Fig. 2. It is shown, however, as mounted in a modified form of housing, consisting offa lower casing it having an end wall I II and an intermediate wall H2 re-' spctively at the ends of the horizontal duct 80, and in which the whole assembly is supported, as by'welding. The housing H0 supports a vertical casing H4, conveniently of cylindrical form, surrounding the upright portion 82 of the firing tube. The housing H4 desirably is provided with an opening H5 for lighting the burner ring 96 and to provide, with openings in the walls Ill and I [2, the secondary air for the flame from that burner ring 96.

' Thehousing l lilll4 desirably supports the firing tube duct-80, the oil line 88, and the gas line in the same relative positions as the firing tube assembly of Fig. 2, so that this assembly can be connected to the same operating unit.

This modified assembly of Fig. 6 may be car-.

a,s,,,thatin Figs. l to l7,,During.pstand by;operation, to maintain the lower portion of the gasifying chamber 93 at initial gasified temperature, h eas;;burner;sol-burns ontinuou ly, and the pilot burner 88 provides .acontinuous ,pilot., fiame-. oil supply is under constant level control at [a level near the bottom, of .the asifying, chamher 83, at about the level of the section line8-8, r-mand is under the control of a shut-ofi, valve and a metering valve as in the case ofthe unit of Figs. 1. to 4. as the oil ,Shut'ofi valve isopened,

oilfiowsslowly into the ,gasifying chamber 83, comes, into contact with the. heated, bottomsuriac es thereof, and is immediately gasifiedi'f The gas so produced flows into and through the channel 9i] to the manifold lgz-and hence through the ports,- 92 into the firingtube. The gas is there combustible mixturewhich is ignited by the pilot burnerQB; The starting. cycle of combustion curs in-the same progressive way as in the firing tube of Fig. 2, and when such combustion is well established, the blower is turned on in response to the temperature within the firing tube, by operation of the thermostatic device 50.

I claim as my invention:

1. An oil-burner, comprising a generally cylindrical firing tube, means forming an annular gasification chamber about the forward flame-discharge end of said cylindrical firing tube and contiguous therewith, the lower portion of said chamber being of oil-retaining form, means forming an annular manifold about the cylindrical firing tube immediately behind the annular gasification chamber and communicating therewith at the top thereof, said manifold being defined in part by the wall of said firing tube, said manifold having a circumferential series of gas-emission ports through the firing-tube wall thereof, said ports being directed at an angle of not to exceed 90 r to the cylindrical wall extending forwardly therefrom and being spaced about the periphery of said firing tube and said manifold being otherwise closed, and an oil inlet adjacent the bottom of said gasification chamber, means to admit air at the rear end of said firing tube, whereby oil fed to said firing tube will be gasified adjacent said inlet and the resulting gasified oil will be heated by traverse of the firing-tube wall and will be discharged immediately at high temperature into said cylindrical firing tube in a plurality of circumferentially spaced streams directed into confiuence with air fiow therethrough toward its flame-discharge end, and the entrance of air to said manifold and gasification chamber will be prevented.

2. An oil burner, comprising a generally cylindrical firing tube disposed generally horizontal and having a forward fiame discharge end, means forming an oil gasification chamber surrounding the flame-discharge end of the firing tube contiguous with the outer surface of its wall, the lower portion of said chamber being of oil-retaining form, an oil inlet to said lower portion of said gasification chamber, means forming a manifold yrxmixed with air under natural draft tosform a -around-;, the:firing tube immediatelyv behind the asification chamber and-communicating therewith thrgughalgas outlet port atthe top thereof, aid -manii.old'.-being defined in part by. the cylindricalzwall of the firing tube, the firing-tubeyvall oi thegmanifold havinguaseries of, gas-emission ports therethrough; spaced around the periphery of, said firing, :tube, said; ports being. directed at angle of not to-exceed 90 ,110 the walle'atending forwardly therefrom, means to admit oil through said ,oil inlet at a metered. rate, and: means to farce; air through-said firing tube past .saidqgasemission openings-toward the fiamesdischarge end;--.whereb-y; oil admitted to said gasification chambergasified adjacent the bottom thereof and traverses alargeareaof firingetube. wall to be highly heated beforaentering said: manifold, and admixture of .air therewith is avoidedprior its emission into said firing-tube.

3'. ;An oil burner as defined in claim 2, in which said; oil jaclmittingmeangcomprises an oil-supply line torsaid oillinlet, a-metering restriction iii-said line and aconstant level device in said oil-supply lineairomwhich oil flows bygravity, through-said striction to said oil inlet \and which. limitsithe l-headin said line to the gravity head from. an oii level in said device below the outlet port from the, gasification chamber, thereby:v providing a i eteredimpositiveilow-pressure oil supply tosaid 30 oil inlet adapted tobeuregulated byabnormally highgas. pressures in said. gasification chamber.

d. An oil burner as defined in claim 2, in combination with ignition means for said firing tube, an oil-supply line to said oil inlet, a constant level device in said oil-supply line from which oil flows by gravity to said oil inlet and which limits the oil-head in said line to a gravity head from an oil level in said device below the outlet port from the gasification chamber, a metering restriction and a shut-off valve in said oil line downstream from said constant level device, and stand-by heating means to heat to initial gasifying temperature prior to oil admission, a bottom wall portion of the gasifying chamber which receives oil initially supplied through said oil line upon the opening of said shut-off valve.

5. An oil burner, comprising a firing tube having a forward flame-discharge end, means forming a gasification chamber about the flame discharge end of the firing tube and contiguous with the outer surface of its wall, means forming a manifold adjacent the rear end of the gasification chamber and communicating therewith through a gas outlet port at the top thereof, a series of gas emission ports from the manifold to the firing tube spaced around the periphery of the firing tube and opening thereto at an angle to avoid entrance thereinto of forwardly flowin air in the firing tube, said gasification chamber being adapted to retain oil below said top gas outlet port, an oil inlet adjacent the bottom of the gasification chamber, means to force air through said firing tube forwardly past said gas emission ports, an oil-supply line to said oil inlet, and a constant level device in said oil-supply line from which oil flows by gravity to said oil inlet and which limits the oil head in said line to a gravity head from an oil level in said device below the outlet port from the gasification chamber, thereby providing an impositive low-pressure oil supply to said oil inlet.

6. An oil burner as defined in claim in combination with a meterin restriction in the oilsupply line between said constant level device and said bottom inlet to the gasification chamber.

11 7. An oil burner, comprising a firing tube having a forward flame-discharge end, means to pass air forwardly through said firing tube, means forming a gasification chamber about the flame discharge end of the firing tube and contiguous with the outer surface of its wall, means forming bottom of the gasification chamber, ignition means for said firing tube, an oil supply line to said oil inlet and containing a metering restricti'on and a shut-off valve, stand-by heating means to heat to initial gasifying temperature prior to oil admission a bottom wall portion of the gasifying chamber which receives oil initially supplied throughsaid 011 line upon the opening of said shut-off valve, the heat stored in said bottom Wall portion by said stand-by heating means being thereby utilized to vaporize the initial metered supply of oil for initial combustion of oil vapor in said firing tube.

8. An oil burner as defined in claim 6, in combination with means to force combustion-supporting air through said firing tube.

9. An oil burner as defined in claim 7 in combi- 12 nation with control means operable subsequent to the opening of said shut-off valve to activate said forced-air means.

10. An oil-burner as defined in claim 7 in combination with control means operable subsequent to the closing of said shut-off valve to inactivate said forced-air means.

GEORGE M. BURGESS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 668,856 Levrechon Feb. 26, 1901 1,684,288 Smith vet a1 Sept..11, 1928 1,690,015 Johnson Oct. 30, 1928 1,753,145 Grant Apr. 1, 1930 1,761,537 Ravenor June 3, 1930 1,977,478 Hawley Oct. 16, 1934 2,117,968 Lutherer May 17, 1938 2,313,568 Miller Mar. 9, 1943 2,363,192 Miller Nov. 21, 1944 FOREIGN PATENTS Number Country Date 319,404 Great Britain Sept. 23, 1929 451,452 Great Britain Aug. 6, 1936 634,194 Germany Dec. 16, 1937 636,448 Germany Oct. 9, 1936 Certificate of Correction Patent No. 2,561,264 July 17, 1951 GEORGE M. BURGESS It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 1, line 39, for part of read part in; line 42, for to gasifying read to a gasifyz'ng;

and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent Otfice. Signed and sealed this 25th day of September, A. D. 1951.

THOMAS F. MURPHY,

Assistant Commissioner of Patents.