US2091600A - Oil burner - Google Patents

Description

Aug. 31, 1937. w. Gf LATIMER OIL BURNER Filed Sept. 2, 1952 3 Sheets-Sheet 1 Aug. 31, 1937. w. G. LATIMER v 2,091,600

OIL BURNER Filed Sept. 2, 1932 3 Sheets-Sheeil 2 n /IIIIIIIIIIII'IIIIIIIIIIIIIIIIIIL INVENTOR Pt/lliam G. Latimer ll/llll/M ATTORNEY Aug. 31, 1937. w. G. LATIMER OIL BURNER Filed Sept. 2, .1932

3- Sheets-Sheet 5 INVENTOR I/'lliam G. Latimejr BY /P y f TTORNEY Patented Aug. 31, 1937 UNITED STATES entrar ori-ice OIL BURNER poration of Michigan Application September 2, 1932, Serial No. 631,571

2 Claims.

The present invention relates to heating systems and more particularly to burners using oil for the fuel. This application is a continuation in part of my copending application S. N, 488,521,

5 filed October 13, 1930, now Patent No. 2,011,901.

An object of the invention is to provide a safety valve in the fuel line forI preventing the flooding of the burner in the event of abnormal operation. T'o carry this out I provide a continu- `l ous operating motor for supplying air for supporting combustion and utilizing a governor operated by the motor for maintaining the safety valve open only as long as the motor is operating normally and also utilizing a thermostat respon- 15 sive to the temperature of the burner for maintaining the safety Valve open only when the burner is heating above a predetermined minimum temperature.

Other and further objects and advantages will 20 be apparent from the following description, reference being had to they accompanying drawings wherein a preferred embodiment is disclosed.

Figure 1 is a vertical central longitudinal section through the burner;

25 Figure 2 is a top plan View with parts thereof shown in section;

Figure 3 is a View similar to Figure 1 showing the burner frame in section, the section being taken on line l-4 of Fig. 2;

30 Figure 4 is a sectional view taken on line 5-5 of Figure 3;

Figure 5 is a bottom plan View of a portion shown in Figure 3.

Figure 6 is a sectional top plan View of the end 35 of the burner;

Fig. 'I is a fragmentary plan View, showing the governor control mechanism illustrated in Fig. 2 but on a larger scale;

Fig. 8 is a view of the mechanism shown in Fig.

40 7 but showing the arm S2 in a different position;

Fig. 9 is a sectional view taken on line l2--I2 of Fig. 2;

Fig. 10 is a perspective View of a thermostatic control mechanism;

Ll5 Fig. 11 is a cross sectional and fragmentary View of the gas burner shown in Fig. 1 but on a larger scale.

A shelf C is provided for supporting the motor H. This shelf is preferably formed integral with 50 a vertically extending plate C which forms a closure for the fuel door opening of a furnace. Projecting inwardly from this plate or closure and preferably formed integral therewith. is a `cylindrical casing C2 which extends to substan- 55 tially Vthe central plane of the furnace fire pot and has mounted at its inner end a rotary burner as hereinafter described.

The burner is of that type in which the fuel is fed outward over a revolving disc and is discharged from the periphery of this disk to pro- 5 duce the flame. However, the construction differs radically from those usually employed, first, in the manner of feeding and distributing the liquid fuel thereon and second, in the means employed for preventing combustion or overheating l0 of the fuel until it is discharged from the periphery of the burner disc, the detailed construction being as follows:

D is a disc preferably formed of sheet metal and integral and coaxial with a cylindrical sleeve 15 portion D. Between the cylindrical portion D and the disc is a slightly flaring or conical portion D2 which extends outward beyond the plane of the disc and is then return bent at D3 with a substantially cylindrical portion D4 extending 20 backward and merging into the disc. The disc D is mounted upon a spider E which also carries a disc E spaced from the disc D. The spider E is provided at its center with the hub E2 detachably secured to a shaft F preferably by a threaded engagement therewith. This shaft is journaled in bearings G which are preferably carried by an inner tubular housing member G mounted within and secured at C4 to the outer cylindrical housing C2. The opposite end of the shaft F is connected to the shaft of the moto-r H preferably through the medium of a universal joint I-I permitting of slight inaccuracy in alignment. Thus the shaft will be driven at motor speed and will communicate its movement first to the spider E and then to the disc D and sleeve D.

The fuel is supplied to the burner through a nozzle I which is arranged to discharge the. liquid at the base of the flaring portion D2 of the sleeve D'. The sleeve D' extends into a housing G2 at 40 the inner end of the housing G and which forms an air chamber through which air is to be supplied to the burner. The arrangement is such that the sleeve D is in close proximity to an annular bearing G3 in the housing G2 to form prac- 45 tically a sealed joint and beyond this bearing is an annular portion G4 which extends in proximity to the disc D. On this annular portion G4 is mounted a non-revoluble disc J which is spaced from the disc D a sufficient distance to permit the passage outward of the liquid fuel film but close enough toprotect the` fuel from ignition until it is discharged from the periphery of the disc. Thus in operation the fuel discharged from the nozzle I will first come in contact with the outer Cal surface of the conical portion D2 of the sleeve D and through the combined action of capillarity and centrifugal force will be fed spirally outward on the revolving cone. This continues until the fuel reaches the return bend D3 where its progress is checked by the cylindrical return bent portion D4 so that by the time the fuel reaches the disc D it is quite uniformly distributed. From this point centrifugal action causes the film to move radially outward until it is finally discharged from the periphery of the disc D. The operation of the burner will be fully described hereinafter, but the effect of the mechanism thus far described is to produce a uniformly distributed lm of liquid fuel upon the. peripheral portion of the disc D and without regard to whether the quantity of fuel discharged by the nozzle I is large or small.

To render the fuel ignitible it is necessary that it should be raised in temperature to near the vaporizing point and to support combustion there must be supplied the proper quantity of air preferably also preheated. The heating of the fuel is eifected by surrounding the disc D with an annular member J which as will be hereinafter explained, is maintained at a temperature above the Vaporizing point of the fuel. rIhus the lm. of fuel which is discharged from the periphery of the disc will be Vaporized when in proximity to the member J and will be discharged from the outer end of said member as a combustible gas burning in close proximity thereto. A portion of the heat of combustion will be conducted back through the member J and will thus maintain said member at the desired temperature. 1t is, however, necessary to first raise the temperature of the member J by other means and to this end I have provided a preheating gas burner K. This is preferably formed by a disc K secured to and extending outward from the disc J and fashioned t form an annular channel K2 which abuts against a flange C3 at the outer end of the tubular housing C2. A gasket K3 seals the joint between the disc K' and flange C3 so as to form a gas tight conduit which communicates at one point with a supply gas conduit K4 extending parallel to the casing C2 from outside the furnace door. The outer wall of the channel K2 is perforated at K5 to form gas jets adjacent to the periphery of the member J', and an annular shield K6 confines the gas within only a restricted channel between the same and a flange J2 upon the member J Thus in starting, when gas is supplied through the conduit K4 it will burn just outside the restricted passage between the member K6 and fia-nge J2 and will supply suicient heat to the. member J for the initial vaporization of the liquid fuel.

The air for supporting combustion is supplied to the llame through the space between the discs D and E. This space communicates through the interior of the sleeve D' with the chamber with'- in the housing G2. Mounted on the housing G2 is a damper or air valve L which when open will establish communication between the chamber in the housing G2 and the space within the cylindrical housing C2. Th-e air is propelled longitudinally through the housing C2 by means of a suitable fan O or other air propelling device driven by the motor, and as shown this fan is mounted upon the. universal joint I-l and is arranged within a housing O between the motor H and the flange C. Whenever the damper L is opened a portion of vthis air will pass into the housing G2 and through4 the space between the.

discs D and E radially outward against the flame. The valve L is preferably thermostatically controlled and to this end is mounted on a rock shaft L passing horizontally outward through the cylinder C2 and having attached at its outer end a spiral thermostat L3 of the bi-metallic type. l/Vh-en the parts are cold the damper or valve L will be substantially closed but after the burner is heated the thermostat L3 by expanding will rock the shaft L and open the valve. The degree to which it is opened depends upon the temperature of the casing which in turn depends upon the size of the flame that is issuing from the burner. Consequently whenever the llame is increased by a greater supply of liquid fuel the increased heat will affect the further opening of the valve L so as to supply additional air for the flame. A further function that is performed by the passage of air through this ourse is the cooling of the shaft and inner portions of the disc E' while the absorbed heat will raise the temperature of the air to increase its efliciency in supporting combustion. Further protection against overheating the shaft and connecting parts is through one or more secondary shields lVl which are arranged outside. of the disc E" to the peripheral portion of which they are attached. Thus air pockets are formed between the shields M and the disc E which lessens the amount of heat that can penetrate tothe disc E.

As shown in Figure l a semi-cylindrical shield N surrounding a portion of the housing C2 forms a channel for the air through which a portion of the air passing inward through the housing C2 will be returned outward through the ports N2 channel N1 and ports N3 and will be discharged outside of the furnace. This circulation of air will be constant during the operation of the furnace and will therefore prevent the overheating of the housing C2 and the air passing therethrough. This in turn will prevent overheating of the bearings G. As a further precaution the inner housing G is supported within the housing C2 by members of restricted cross section such as the screws C4 and dowel pin C5 so that very little heat can be conducted inward through these members.

The gas conduit passes through the shelf and connects to pipe K4 leading to the burner K.

The .amount of fuel fed to the burner may be either manually or automatically controlled. Preferably it is automatically controlled through thermostatic means actuated by room temperature and serving to open or close the liquid fuel supply valve. Any suitable construction may be employed for this purpose and as this. forms no part of the present invention further description is omitted.

The valve for controlling the admission of fuel may be located at any convenient point external to the furnace but in order to guard against accidental discharge of fuel an automatic control valve is also employed. This valve R is preferably of the diaphragm control type and is located adjacent to the shelf C. As shown, it is beneath the shelf and comprises a ball R centrally above a flexible diaphragm R2 having the stud R3 secured thereto which when moved upward Will press the ball to its seat. Beneath the diaphragm R2 is a lever R4 having one arm engaging the stud R3 and its opposite arm provided with a weight R5. The arm of the lever which engages the stud R3 also bears against a vertical rod R6 which passes through the shelf C and upward through the casing O and being provided at its lower end with a ylaterally lextending arm #R7 passing out from said casingand having a handle R5 in a position for manual operation toliftthe' rod R6. S is a movable stop which in oneposition is in the path of the rodR6 so as toipreventthe lifting of the rod R5. This stop is provided with a slot which receives a'stud VS1' which extends downwardly from the free end of a horizontal lever S2 fulcrumed at S3 and bifurcatedi to embrace the shaft F. l* f Upon the shaft F is a centrifugal `governor T having a slidablesleeve T actuated by a spring T2 lto bear against the lever S2vin a direction to withdraw the stop kS from'tliepatlfiV of the rod R6. The sleeve is actuated in the opposite direction by links T3 connecting itto the Weighted arms T4'. Arms'T4 are pivotally carried by a collar'l."5 secured to a shaft F, whicharm's, when' thrown out centrifugally,` will overcome the tension of "spring T2. The stop S is also connected to a horizontal rod S4. which extends inward through the housing C2 through a bearing S5 on the housing G2. A spring S6 between this bea-ring and a collar S7 on the rod yieldably holds the stop S extended to be in the path of the rod R6.

In the event the fuel heating member J should cool to such low degree that the fuel is not properly vaporized to support proper combustion, as for example, in case the fuel supply is exhausted, means is provided for preventing flow of fuel to the burner after the fuel tank is replenished. A bi-metallic thermostat U, similar to spiral thermostat L2, is employed for this purpose. This thermostat when cooling will rock a bell-crank lever U1 which in turn will move the rod S4 to the right (as viewed in Fig. 4) causing stop S to move to the right. The bell-crank lever Ul is loosely mounted on the rod L' and comprises an arm U2 which lies in the path of spiral thermostat U and is engaged by the end of the thermostat and forced upwardly when the thermostat cools. The bell-crank lever U1 includes a depending arm U3 arranged to engage the projection S8 on the rod S4.

The spiral thermostat U being disposed adjacent the heating ring J1, it is responsive to the temperature thereof, therefore when the ring cools the thermostat will cool to rock the bellcrank lever U1 causing the arm U3 to move the projection S8 to the right. This movement causes the stop S to release rod R6 whereby the weight R5 is effective to close the valve R1 to shut off the flow of fuel to the burner.

As long as the motor is operating at its proper speed and as long as the ring Jl is heated above a predetermined minimum temperature, the stop is over the rod R.G and maintains the safety valve R1 open. However, on failure of proper motor operation or on decrease of temperature of the ring J1, for any reason, below a predetermined minimum, the stop S is moved to render the weight R5 effective to close the valve R1.

If it is desired to immediately run the burner the gas starter may be first lighted before the insertion of the burner and is then run for a sufficient length of time to do the preliminary heating. The thermostat U will then be heated sufficient to release the stop S so that the spring S6 will be free to move said stop S over the rod R6 when the said rod is depressed. The motor is then started which communicates rotary motion to the shaft F and disc Dafterwhich theliquid fuel valve is opened by depressing rod R6 by pushing downwardly on handle R8 which is connected with arm R7.

through the nozzle I. The thermostat U then This permits the feeding of the fuel f bei-iig heatedfthespring'Si will move the stop S over rod `R-after the-'motor attainswits normal operating? speed and has retracted sleeve T1. Fuel, as beforey described, passes-first on the inclined or flaring `portion D2 of the sleeve around the return bend D3 and? back on to the face of the'.disk\D."Thelouter portion of the disc has already been heated so vthat' the film of oil passing radiallyoutward meeting thehot portion of the disc will be vaporized and will issue as `a stream of gasffrom the' periphery of the disc. "At the same time air which has passed from the fan through the space within the conduit C2 will reach the partly open valve L and a portion will passv into" the housing G2 and then through the spacebetween thediscs D and E, striking against the ameat the periphery of the disc. This will support smokeless combustion but as the air is not commingled'with the gas until the air reaches the peripheral outlet'for the fuel, the name will be white. In other words, a flame that is high in radiant heat is produced, this being the most efficient way of heating the furnace. The construction is one which requires very little atten- ,tion after it is once started, but if for any reason it should be required to clean the burner this may be easily accomplished by swinging the burner out from the furnace chamber and detaching the rotary disc from the end of the shaft.

The annular groove which is formed by the return bent portion D3 of the disc constitutes in eifect a well in which a certain amount of the liquid fuel is temporarily detained. The larger the capacity of this well the longer the fuel will be detained, which modies both the degree of heat which is imparted to the fuel and the cooling effect' on the disc. Due to this fact I am enabled to adapt my burner for either mild or very cold weather by merely exchanging discs. Thus the greatest efficiency is obtained when the burner is operating low, as in the spring and fall of the year, when used with a disc and a comparatively shallow well but in mid-winter greater elliciency is obtained by using a disc having a deeper well. The changing of the discs is so easily effected that this method of operation may be much more satisfactory than retaining the one construction for all seasons of the year.

Where the burner is operating low, it is highly desirable to maintain uninterrupted feeding of the liquid fuel as otherwise there would be danger of the burner going out. It is, however, difficult to maintain a continuous liquid stream where the quantity is small but I have avoided this difficulty by placing the discharge end of the nozzle I in very close proximity to the surface D2 on which the liquid is discharged. This has the effect of maintaining the continuity of the liquid stream due to capillarity, whereas if the nozzle were spaced further from the revolving surface the liquid might break up into drops.

Furthermore, a positive propulsion force for the fuel is exerted as an air seal is formed which prevents back atmospheric pressure against the fuel in the nozzle and therefore a suction effect is produced by the revolving disc. 'I'hus the liquid fuel will be fed successfully however small the quantity.

By my improved arrangement, the fan O not only supplies air for supporting combustion, but also provides for cooling the moving parts of the burner within the furnace. A blast of cool air is continuously forced over the moving parts to thus keep them sufficiently cool even though the air valve L is closed, or substantially closed.

Some air at all times, is permitted to flow over the working parts, which air expelled through the ports N2 channel N1 and ports N3 to the exterior of the furnace or through the housing U4 for the bell-crank U1 and thermostat U, Which housing opens into the furnace and air passing through said housing U4 prevents excessive heating of these operating parts.

While the form of embodiment of the present invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, all coming Within the scope of the claims which follow.

What I claim as my invention is:

1. A fluid fuel burner comprising in combina tion, a rotating fuel feeding device, a fuel line, a valve in the fuel line, said valve being urged normally to a closed position, means responsive to a predetermined temperature of the oil burner, means responsive to the speed of the rotating device, and a latch cooperating with the temperature responsive means and to the speed responsive means and connections between said latch and said temperature and speed responsive means, whereby said latch is rendered operative to hold said valve open only when the burner temperature and the speed of the rotating device simultaneously exceed predetermined minimum values.

2. A fluid fuel burner comprising in combination, a rotating fuel feeding device, a fuel line, a valve in the fuel line, said valve being urged to a closed position, means responsive to a predetermined speed of the rotating device, means responsive to a predetermined temperature of the oil burner, and a latch cooperating With the speed and temperature responsive means and dependent jointly upon the speed of the rotating device being normal and upon the temperature of the oil burner being normal for holding the valve open.

WILLIAM G. LATIMER..

Images