US3126939A - de lancey - Google Patents

Description

March 31, 1964 w. H. DE LANCEY 3,125,939

AIR CONTROL FOR OIL BURNERS Filed Deo. 13, 1961 5 Sheets-Sheet 1 INVENTOR. Mar/M AMA/ffy Or @m ,rvzA/y March 31, 1964 w. H. DE LANCEY 3,125,939

AIR CONTROL FOR OIL BURNERS Filed Dec.- 13, 1961 5 Sheets-Sheet 2 /3 5:51 A 45 44 lak 4 INVENTOR. wm/ A. Amm/:ff

March 3l, 1964 w.H. DE LANcEY 3,126,939

AIR CONTROL FOR OIL BURNERS Filed Dec. 13, 1961 3 Sheets-Sheet 3 Pi I Z5 j ig-5 INVENTOR BY zweer/4. Arun/cq United States Patent Office 3,126,939 Patented Mar. 31, 1964 3,126,939 AIR CUNTRL FR H, BRS Warren H. De Lancey, Zanesville, (bliio, assigner to Hardel Laboratories, Zanesville, Gino, a co-partnership Filed Dec. 13, 1961, Ser. No. 160,41?. 2 Claims. (Cl. l58 ltl5) This invention relates to a primary air adjustment and combustion head for an oil burner.

The present invention is particularly directed to conventional high pressure atomizing types, however, the present method of air control may also be adapted to other types of forced draft burners.

The present air control is adapted for use in conjunction with an oil burner which includes an electric motor which drives an oil pump for supplying oil to an atomizing nozzle under pressure and also drives a blower wheel for delivering air into the combustion tube of the oil burner to the combustion head, where it is mixed with the atomized oil and ignited by a conventional type of electrodes and burned in a suitable combustion chamber.

Normally the oil burner lires at various rates depending upon the amount of heat required. This firing rate is mainly controlled by the size of the orifice in the atomizing nozzle, and to a lesser degree by the pressure of the oil delivered by the pump.

Since the amount of air required is directly in proportion to the amount of oil, it is therefore necessary to have a means of adjusting the primary air.

In a conventional type of oil burner assembly, the blower wheel is of a centrifugal type and as such, the amount of air it will deliver is very sensitive to pressure variations, either on the inlet or discharge side. Heretofore, most oil burner air adjustments have been on the inlet side of a blower wheel, normally consisting of a shutter mechanism. These have a number of disadvantages: the oil burner re is not absolutely steady due to the diiiiculty of obtaining a continuous and uniform mixture of air and oil at all points and the hiUh rate of llame propagation. There are minor variations present always which can be really accentuated by acoustical conditions in the combustion chamber and heat transfer passages.

These result in pressure variations which are felt against the end of the blower tube. If there is no provision within the blower tube to stop this pressure wave, it will travel back to the blower wheel where the air delivery will be momentarily sharply reduced.

This reduction of air delivery causes the fire to partly collapse with a sudden decrease in the hot products of combustion, and therefore a decrease of pressure within the combustion chamber. A low pressure wave is then set up and air delivery increases suddenly.

Under proper conditions, this cycle can become rhythmic and violent. It is then called pulsation. It is the cause of substantially all combustion noise from oil burners, and it is the primary object of the present invention to eliminate this pulsation or noise.

It is therefore, the object of the present invention to provide a primary air adjustment for an oil burner which is placed on the discharge side of the blower wheel upon the interior of the blower or combustion tube. Y

It is a further object of the present invention to provide a primary air control on the discharge side of the blower and within the combustion tube, which consists of an apertured llow control ring sealed within the combustion tube and upon the far side thereof a control cup, which is normally spaced from and variably spaced from the said ring for regulating the amounts of air which pass through the said ring and through the outlet of the oombustion tube.

The present invention also contemplates a means by which a manual control may be provided remote from the said control cup upon the exterior of the oil burner and for regulating the spacing of the said control cup with respect to the air control ring.

It is a further object of the present invention to provide an air control mechanism in the nature of a control cup which in perfect alignment with the air control ring and movable towards and away therefrom and centrally spaced with respect to the combustion tube so that at all itimes the opening between the said ring and control means 1s uniform, and furthermore so that the air passing between the said ring and control cup is deflected and held ina uniform torus without substantial eddys by the cylindrical outer surface of the cup and the cooperating interior cylindrical surface of the combustion tube. It is a further object of the present invention to provide 1n conjunction with the combustion tube a cone-shaped outlet therefor, with vane means mounted thereon, and 1n angular relation to the longitudinal axis of the combustion tube for giving an axial and rotative swirling motion to the combustion air, as it is delivered through the outlet of the combustion tube and for homogeneous mixture with the oil being sprayed from the orilice of the oil supply tube. i

It is a further object of the present invention to provide the primary air adjustment on the pressure side of the burner to thus provide for building up of a full static pressure back of the adjustable control orifice. By making this pressure in excess of any variationsin the combustion chamber due to llame variations, the air metering through the combustion tube is much more uniform and the noise level sharply reduced.

By establishing a high static pressure on the blower side, it effectively dampens out rhythmic pulsations and throb, while delivering an extremely uniform air pattern.

These and other objects will be seen from the following specification and claims in conjunction with the appended drawings in which:

FIG. l isa rear elevational view of the oil burner assembly as viewed from the firing end thereof.

FIG. 2 is a left side elevational View thereof, partially broken away and sectioned for illustration.

FIG. 3 is a fragmentary section taken on line 3 3 of FIG. 2, illustrating the adjustable air control cup.

FIG. 4 is a fragmentary section taken on line 4 4 of FIG. 3.

FIG. 5 is a fragmentary section on an increased scale taken on line 5 5 of FiG. 2 illustrating the air control ring.

FIG. 6 is a section taken on line 5 6 of FIG. 5, and with the control cup shown in phantom lines in the normal operating position with respect to said ring.

FlG. 7 is an end View taken on line '7 7 of FIG. 2 illustrating the vane arrangement on the outlet cone of the combustion tube.

-It will be understood that the above drawings illustrate merely a preferred embodiment of the invention, and

that other embodiments are contemplated within the scope of the claims hereinafter set forth.

Referring to the drawings, the present oil burner construction is of a conventional high pressure atomizing type. However, the present air control method hereafter described, is equally applicable to other types of forced draft burners.

The oil burner assembly generally indicated at 11, FIG. 1 includes a pair of hollow opposed casing elements 12 which are interconnected at their upper portions as at 13, FIG. 2, and include registering side flanges 14 and 15, by which the housing halves are lixedly secured together as by fasteners 16, FIGS. 1 and 2, to thus dene the chamber `17 within the upper portion of the burner housing within which is suitably journaled the blower wheel 18.

The electric motor 19, energized as at 2i), includes a mounting flange 21 lfor securing assembly with respect to the housing 11, and there is provided a driven tube 22 within the motor housing, which projects into the charnber 17 and is joined as at 23 to the blower 1S.

The motor 19 also includes an internal driven shaft 24, which is axially mounted within the tube 22, which is operated by the said motor employing a centrifugal clutch, C. This centrifugal clutch C actually forms no part of the present invention, but the detail thereof is disclosed in vmy copending patent application, Serial No. 35,620, tiled June 13, 1960, now Patent No. 3,082,335, and relating to a clutch motor. Suiiice to say that the said clutch motor is of a centrifugal type so that when the Kmotor 19 is initially energized, the rotor drives the tube 22 initiating rotary movement of the blower 18. After the tube has achieved suicient speed, the clutch mechanism lwithin the centrifugal clutch C, moves in such a manner as to establish a driving connection with the shaft 24 to thus transmit driving motion through the flexible coupling 25 to the driveshaft 26, journaled within the hub 27 of the oil pump 28, which is anchored as at 29 within the outwardly projecting boss 44 on the oil burner housing 11, as best shown in IFIG. 1.

The Iboss 44 includes an internal shoulder 46, which cooperatively receives shoulder 27 forming a part of the pump 28, completing the assembly of the said pump with respect to the oil burner housing 11.

The oil burner power operated pump 28 is connected -to a source of supply of Ifuel oil and includes an outlet 30, FIG. 1, which joins as at 31, through housing wall 32, the end of the oil supply pipe 47 which is positioned within the interior of housing l11 adjacent its lower portion and which projects outwardly thereof axially of and centrally of the combustion tube 38, hereafter described.

yThe lower portion of the oil burner housing has on its opposite sides the ignition transformer housing extensions 33, FIG. 1 including the high voltage transformer elements 34 with connected bus bars 35, FIG 2, which are connected to the inner ends of the pair of conventional electrodes `36, which are positioned within the burner housing 11, and which also extend axially into the combustion tube 38.

The outer wall 37, FIG. 2, forming a part of the housing 111, is suitably apertured for communication into the combustion tube 3S into which air under pressure is delivered from the power operated blower 18.

The hollow cylindrically shaped elongated combustion tube 38 at its inner open end has an annular flange 39 facilitating assembly, as best shown in FIGS. 2 and 7, between the end wall 37 of the housing and the assembly flange 40 on the mounting ange 41, which is provided with a series of spaced apertures 42, providing a means by which the said mounting flange may be secured to some portion of a `furnace or housing lfor a combustion chamber, in a conventional manner.

The fasteners 91, lFIGS. 1 and 2 provide a means for interconnecting and securing combustion tube with respect to the mounting flange 41-40, and the corresponding apertured end wall 37 of the burner housing 11, and by which air under pressure is delivered into the chamber 43, within the said combustion tube `for movement therealong and Ifor subsequent delivery through outlet 53, FIG. 2.

The boss 44, has grilled openings 45 therein, as best shown in FIG. 2, providing the air intake 4for the power operated blower 18 by which air under pressure is de livered -frorn the said housing 11 into the combustion tube 38.

The above described oil pipe 47 extends axially into the chamber 43 of combustion tube 3S and mounts at its outer end the adapter 4S for adjustably securing the nozzle 49, centrally apertured at `5i?, delivering an atomimd spray of combustion oil in a pattern, such as shown in FIG. 2, and for intermixing with the controlled air supply indicated by the arrows, FIG. 2, and in the manner hereafter described.

The combustion tube 38, also known as a firing tube, includes the firing tube cone 51, including an internal annular flange 52, which is assembled upon the outer end portion of the tube 33, and xedly secured thereto, which cone has a converging outlet portion terminating in the outlet 53 for the ignited combustible mixture in a reasonably conventional manner.

A series of angular vanes 54 are arranged upon the interior of the outlet cone 51, so as to extend at an acute angle with respect to the longitudinal axis of the combustion tube 3S, and include the flanged members 55, which are secured to the interior annular portions of the flange `52, forming a part of the outlet cone 51, as best shown in FIGS. 2 and 7.

The purpose of the vanes 54 is to provide a uniform rotary and swirling motion to the controlled air supply, as indicated by the arrows, as it moves forwardly and outwardly through the outlet 53 in cone 51, and to further assure uniform mixing of air with the atomized fuel.

Referring to FIGS. 2, 5, and 6, an air control ring 56 is spaced transversely within combustion tube 38 intermediate its ends, and includes a ycentral mounting hub 57, axially apertured at 51S, for adjustable mounting upon oil tube 47, being secured thereon as by the set screw 59, FIGS. 2 and 6.

The ring 56 includes the spaced integral arm 66 and the pair of additional integral arms 6'1 to thus pro-vide an apertured central portion 96 for the said control ring, through which primary air will pass in a manner hereinafter described.

The control ring 56, integrally formed with respect to the arms 60 and 61, has annular rim portion 62, and the outer annular flange 63, transversely apertured at 64. The inner surface portion of the ange 63, forming a part of ring 56, is tapered annularly outward of progressively increasing diameter, as at 65. Annular notch 66 is formed adjacent the rear portion of the rim and flange assemblies 62-63 and cooperatively receives, as shown in FIG. 2, the flexible O-ring seal 67, which is retained upon the said ring and snugly with respect to the interior surface of the combustion tube 33 by means of the retaining ring 68 and associated fasteners 69, FIG. 2.

Two of the arms 61, forming a part of said ring, have bosses 71 of the clamping type, terminating in the free end portions 72, and which define the transverse apertures 70 for supporting and receiving the insulating sleeves 75, which are mounted upon the respective electrodes 36, and which thus project through the ring 56, and at their outer ends converge in a conventional manner in spaced relation and adjacent the orifice 50 of the nozzle 49, for ignition purposes in a conventional manner.

The extensions 72, as shown in FIG. 5, are normally spaced from the arms61, as at 73, and are ixedly and adjustably secured with respect thereto as by the fastening screws 74 to provide a firm engagement with respect to the said insulated electrodes.

As shown in FIG. 2, the assembly washer 76, is interposed between one end of insulator 75 and electrode 36,

and at the opposite end there is an assembly nut 77 mounted over the said electrode and retainingly engaged by the elongated coil spring 78, mounted on the said electrode 36, as best shown in FIG. 2.

One of the integral arms 60 forming a part of the air controlled ring 56 has a central enlarged boss, which is apertured at 79, transversely therethrough as shown in FIG. 6, and is adapted to receive the threaded end of the manually rotative shaft 80, which is movably positioned within the housing 11, and extends into the combustion tube 38, and loosely through the aperture 79 in the arm 60.

The outer end portion of the shaft 80 projects through the depressed portion 81 in the wall of the housing 11, opposite from wall 37, FIG. 2, and has secured thereon a knurled knob 82, which provides the means of rotating the shaft 80 to control longitudinal adjustments of the control cup 85, hereafter described.

The outer end of the shaft 80 is threaded as at 83, operatively extends through the interiorly threaded bore 95 of the longitudinally adjustable control cup 85, shown in FIGS. 2 and 4, there being a retainer ring 84 upon the outer end portion of the shaft 80.

The control cup 85, is arranged transversely upon the interior of the combustion tube 38, and includes the radial plate 86 of disc-form, including an annular ange 87, and the internal hub 88, by which the said cup is slidably and adjustably mounted upon the oil pipe 47, as best shown in FIG. 2.

The cup assembly 85--86-87 is in accurate longitudinal alignment with the control ring 56, and is normally spaced with respect to the tapered outlet 65, forming a part of the said ring, as indicated in dotted lines, FIG. 6, and thus is adapted to control the flow of air under pressure through the said ring apertures 96 and into the interior of the combustion tube 38.

The spacing of the control cup 85, with respect to the ring 56, determines the quantity of air under pressure, which is transmitted through the ring 56 throughout the length of the combustion tube 38, as indicated by the arrows, FIG. 2.

The cup plate 86, has an interiorly threaded bore 95, which is adapted to receive the threaded end 83 of the control shaft 80.

Accordingly, rotary movement of the said shaft through its knob 82 in one direction or the other will effect corresponding longitudinal adjustments of the cup 85--86, with respect to the air control ring 56. Thus there is provided a manually operative means on the oil burner housing for effecting by remote control longitudinal adjustments of the cup 85-86-87 with respect to the air ring 56, and thus providing a manual control means for regulating upon the far side of the blower outlet, the amount of air under pressure which will pass through the ring 56, into the interior of the combustion tube 38 for transmission towards its outlet end.

Except for the members 60 and 61, the ring 56, being apertured at 96, is substantially unobstructed for transmission of combustion air therethrough. By turning the knob 82 on shaft 80, the air control cup 86-87, may be slidably adjusted upon the oil pipe 47, so as to obstruct or almost close the central opening of ring 56.

On the other hand, the cup may be moved forward toward the nozzle to substantially increase the air passage. These parts, namely the cup and the said ring, are accurately aligned so that the opening between them is uniform at all points. The air passing through the ring is deected forwardly by the annular curved surface 65, shown in FIG. 6, and is held in a uniform torus, without substantial eddys, by the cylindrical outer surface of the annular flange 87 of the cup 85-86.

This uniform torus of air upon the interior of the combustion tube 38 passes forward where it strikes the vanes 54 in burner end cone 51. These vanes give the moving air axial motion and also a swirling rotary motion y 6 and cause the air to leave the cone through the outlet 53 in susbtantially the same pattern as the oil spray, indicated in dotted lines projecting from the nozzle outlet 50.

The base wall 86 of cup 85-87 also has a plurality of spaced arcuate slots 89 therethrough, FIGS. 3 and 4, to permit the passage of a small percentage of the total air from the power operated blower 18.

This air is not given a rotary motion by the vanes 54, in the end cone 51, but mixes directly with the oil spray from the nozzle 49-50. This is necessary in order to stabilize the re at this point.

Accordingly in conjunction with the present invention, the air adjustment for the primary air is placed on the discharge side of the blower wheel upon the interior of the combustion tube 38, and includes the air control ring 56 and the adjustable air control cup 85.

The air adjustment on the pressure side of the burner makes it possible to build up the full static pressure of the blower wheel back of the adjustable orifice, namely the control opening between the ring 56 and the corresponding cup 85.

As above set forth, since this pressure can be made in excess of any variations in the combustion chamber pressure due to ame variations, the air metering is much more uniform and the noise level sharply reduced.

By providing for the longitudinally adjustable control cup in an accurate precision alignment with the air control ring, uniform results are produced and a uniform control fiow of air provided to the combustion end of the combustion tube. By this means of establishing and maintaining a high static pressure on the blower side of the burner, rythmic pulsation and throb is effectively dampened, and at the same time, an accurate air pattern is delivered to the combustion end of the burner.

Referring to FIG. l, a pair of opposed upright bracket plates 90, at their inner ends are secured at 91 relative to mounting flange 41. Outer end portions of said brackets have sleeves 92 which supportedly receive the upstanding spaced ends 93 of the horizontally disposed support 94.

As shown in FIG. 2, bracket 97 is anchored by the fastener 98 upon the interior of the housing and is formed at its lower end as at 99 to supportably and rotatively receive the inner portion of the control shaft 80.

As shown in FIG. 3, the control cup has formed Within its bottom wall 86, the bosses 109 of increased thickness with apertures 101 therethrough, which loosely and slidably receive the insulated electrodes 75-76.

Having described my invention, reference should now be had to the following claims.

I claim:

l. In an oil burner, a housing, a power operated blower therein, a combustion tube projecting from said housing adapted to receive air under pressure from said blower, and having a converging outlet for delivering a combustible homogeneous mixture of atomized fuel and air under pressure, an oil delivery pipe within the housing and extending axially into said tube, a nozzle on the end of said tube spaced inwardly of the tube outlet; the improvement comprising an apertured air control ring transversely positioned and peripherally sealed within said tube intermediate its ends, said ring having a forwardly extending tapered annular ange on its outlet side with an internal wall of progressively increasing diameter, an air control cup slidably mounted over said oil pipe aligned longitudinally with said ring, normally spaced between said ring and said outlet and longitudinally adjustable towards and away from said ring, said control cup` having a at end wall terminating in an axial annular wall spaced radially inward of said annular flange and inwardly of the wall of said tube, defining a longitudinally extending annular passage of uniform cross-sectional area, so that the air passing between said ring and cup is maintained in a uniform torus, said cup being of such radial dimension as to variably regulate the air passing through said ring,

and for maintaining a substantially constant static pressure upon said blower, said converging outlet being cone shaped, a series of spaced Vanes secured to and projecting inwardly of said outlet inclined to its longitudinal axis 4for uniformly swirling the air delivered through said outlet, there being a series of centrally arranged slots formed through said cup, at all times passing limited quantities of air therethrough longitudinally of said nozzle to and through said outlet, and a manually movable means adjacent one end mounted on said housing and adjacent its other end operatively connected to said cup for moving the same relative to said ring.

2. In the oil burner construction defined in claim 1, said air control ring being arranged appreciably inward from the tube outlet a distance at least equal to one-half the length of said tube.

References Cited in the iie of this patent UNITED STATES PATENTS 1,412,023 Erickson Apr. 4, 1922 2,156,121 Macrae Apr. 25, 1939 2,181,527 Vollmer Nov. 28, 1939 2,502,664 Nest Apr. 4, 1950 2,753,929 Walshin July 10, 1956 2,796,923 Fiske June 25, 1957

Claims (1)

1. IN AN OIL BURNER, A HOUSING, A POWER OPERATED BLOWER THEREIN, A COMBUSTION TUBE PROJECTING FROM SAID HOUSING ADAPTED TO RECEIVE AIR UNDER PRESSURE FROM SAID BLOWER, AND HAVING A CONVERGING OUTLET FOR DELIVERING A COMBUSTIBLE HOMOGENEOUS MIXTURE OF ATOMIZED FUEL AND AIR UNDER PRESSURE, AN OIL DELIVERY PIPE WITHIN THE HOUSING AND EXTENDING AXIALLY INTO SAID TUBE, A NOZZLE ON THE END OF SAID TUBE SPACED INWARDLY OF THE TUBE OUTLET; THE IMPROVEMENT COMPRISING AN APERTURED AIR CONTROL RING TRANSVERSELY POSITIONED AND PERIPHERALLY SEALED WITHIN SAID TUBE INTERMEDIATE ITS ENDS, SAID RING HAVING A FORWARDLY EXTENDING TAPERED ANNULAR FLANGE ON ITS OUTLET SIDE WITH AN INTERNAL WALL OF PROGRESSIVELY INCREASING DIAMETER, AN AIR CONTROL CUP SLIDABLY MOUNTED OVER SAID OIL PIPE ALIGNED LONGITUDINALLY WITH SAID RING, NORMALLY SPACED BETWEEN SAID RING AND SAID OUTLET AND LONGITUDINALLY ADJUSTABLE TOWARDS AND AWAY FROM SAID RING, SAID CONTROL CUP HAVING A FLAT END WALL TERMINATING IN AN AXIAL ANNULAR WALL SPACED RADIALLY INWARD OF SAID ANNULAR FLANGE AND INWARDLY OF THE WALL OF SAID TUBE, DEFINING A LONGITUDINALLY EXTENDING ANNULAR PASSAGE OF UNIFORM CROSS-SECTIONAL AREA, SO THAT THE AIR PASSING BETWEEN SAID RING AND CUP IS MAINTAINED IN A UNIFORM TORUS, SAID CUP BEING OF SUCH RADIAL DIMENSION AS TO VARIABLY REGULATE THE AIR PASSING THROUGH SAID RING, AND FOR MAINTAINING A SUBSTANTIALLY CONSTANT STATIC PRESSURE UPON SAID BLOWER, SAID CONVERGING OUTLET BEING CONE SHAPED, A SERIES OF SPACED VANES SECURED TO AND PROJECTING INWARDLY OF SAID OUTLET INCLINED TO ITS LONGITUDINAL AXIS FOR UNIFORMLY SWIRLING THE AIR DELIVERED THROUGH SAID OUTLET, THERE BEING A SERIES OF CENTRALLY ARRANGED SLOTS FORMED THROUGH SAID CUP, AT ALL TIMES PASSING LIMITED QUANTITIES OF AIR THERETHROUGH LONGITUDINALLY OF SAID NOZZLE TO AND THROUGH SAID OUTLET, AND A MANUALLY MOVABLE MEANS ADJACENT ONE END MOUNTED ON SAID HOUSING AND ADJACENT ITS OTHER END OPERATIVELY CONNECTED TO SAID CUP FOR MOVING THE SAME RELATIVE TO SAID RING.

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