US2584281A - Pot type oil burner apparatus - Google Patents

Description

Feb. 5, 1952 H. E. MORLOCK POT TYPE OIL BURNER APPARATUS 2 SHEETS-SHEET 1 Filed Dec. 20, 1948 CHAMBER FLOAT INVENTOR. HARRY EMmuocK BY AKA ORA/E Y R 7 5 4 n A Lw 2 a6 "W F 6 w n mw L5 4, 5 w x Feb. 5, 1952 H. E. MORLOCK POT TYPE OIL. BURNER APPARATUS 2 Sl-iEETS-SHEET 2 Filed Dec. 20, 1948 INVENTOR. HA-RI? y 5. Mom. ac K Arf'amwsv Patented Feb. 5, 1952 UNITED STATES PATENT OFFICE POT TYPE OIL BURNER APPARATUS Harry E. Morlock, Medina, Ohio Application December 20, 1948, Serial No. 66,179

7 Claims.

Other more specific objects of the invention I will become apparent from the following descrip-,

tion of the illustrative form shown in the drawings wherein:

Fig. 1 is a side elevation of the burner pot and control cabinet assembly, partly broken away;

Fig. 2 is an electrical control diagram for use therewith; I

Figs. 3 and 4 are plan and central vertical sectional views respectively of the burner, Fig. 3 being partly in section as indicated on Fig. 4; and

Fig. 5 is a fragmentary sectional view showing a modification in an air distributor portion of the burner assembly. The burner or burner pot assembly I, as shown in Figs. 1, 3 or 4, comprises a main hollow metal body casting 2 having a bowl-like bottom portion 3 of generally hemispherical form and an integral annular air receiving and distributing portion 4 including a nearly vertical rim 5 inte rally connected to the bowl-like bottom portion3 by an approximately horizontal ledge or web 6. Supporting legs 1 and 8 (cf. Figs. 1 and 4) adapted to rest on the floor F of any furnace or fire chamber may be connected to the web 6 at boss portions 9 thereof as by screw threads. An electric-motor-operated blower, indicated generally at I ll in Fig. l and located in the control cabinet II which is suitably attached and sealed to the front entrance or doorway D of the furnace (parts of the furnace being indicated diagrammatically), receives air through an opening l2 of the blower casing and delivers it through a pipe i4 130 the burner pot assembly. The air delivered by the blower l enters an annular plenum chamher within the rim 5 of the burner pot casting 2. The chamber is formed or defined by the inher surface of rim 5, lower surface of a burner ring or plate [6 (overhanging the bowl of the burner pot) and the outer peripheral surface of an annular air distributor member I! of sheet metal. Member I! extends from the under side of the burner plate or ring 16 to the ledge 6 and restson theledge. The ledge 6 has an annular rib I8 at its inner limits which locates the distributor ring concentrically of the burner bowl and rim 5 thereof to form the plenum chamber 15. v

The joint between the burner ring I6 and rim 5 of the burner casting is p'referablysealed as by a rope-like asbestos strip l6a which may, be forced into a gap of wedge shaped cross section made by a chamfer on the outer periphery of the ring [6.

Air delivered from the pipe t4 enters the plenum chamber [5 tangentially as shown in Fig.. 3

through a tubular inlet portion |8 of the burner body casting Zand thereby tends to circulate unidirectionally. in the plenum chamberdueto the manner. of inlet and its centrifugal force. The circulating air inthe plenum cha'mberfis admitted at circumferentially spaced regions. 'of the chamber .to the annular space below'the ring l6 through a series of openings 20 inthe ring l1, being aided (in the construction according to Figs. 3 and 4) by baffles 2| bent out.from the metal of the ring H as clearly shown in Fig. 3 into air-current-intercepting relationship to the interior of the plenum chamber l5.

Since considerable pressure is necessarily built up in the chamber l5, due to the nature of the Walls which define it including the relatively restricted area of the openings 20, the air content of the chamber tends to remain in a cyclonic condition as it enters the burner pot- The bent-out form of bafiies 2| distributes the introduced air while encouraging such cyclonic action below the ring or plate l6. An alternative construction of the ring I! is shown in Fig. 5, wherein the metal portions 2| lanced from the ring to form the openings 20 are directed inwardly of the ring at acuteangles to the associated wall portions-of the ring. V

In the case of the bent-out baffles 2| of Figs. 3 and 4, the baflies may extend outwardly uniform distances around the ring I! (not illustrated) or, as shown, may be bent outwardly at progressively increasing distances from the region of the inlet 18 nearly back to said region, so that the various baffles tend to intercept proportional shares "of the annular body of air for uniform distribution thereof to the burner pot. Such incremental interception is not ordinarily necessary because of the pressure built up in the plenum chamber over the pressure in the burner pot. If desired the ring ['1 may be interlocked'as at l'la with'the body 2 as at a notch I'Ia to insure proper placement of the ring in case the baflles are difierently disposed at different portions of the ring, as in Fig. 3. Either illustrated arrangement. of the lanced-out portions (2| or 2|) of the ring I! tends to maintain cyclonic action of the air admitted inwardly through the ring.

Fuel is admitted to the burner pot through a feed tube 25 which enters a bottom cavity 26 of of the bowl portion 3. The lower end of a foraminous or porous low-flame-su'pporting wick or tip 21 occupies the cavity 25 and absorbs introduced fuel therefrom for supporting an initial or low flame such as indicated at A. The amplitude of such flame is determined by the limited rate of admission of fuel to the cavity 26 through the tube 25.

The tip 21 is a rigid porous body preferably of incombustible ceramic material of the nature of fire clay and it may be molded or cut therefrom as desired. The flame may be lighted by a suitable taper, match or electric spark depending upon the elaborateness of the controls.

.The. illustrated control arrangement, to be described later, operates initially to admit only sufficientfuel to the cavity '26 to support a pilot flame Awhich may burn for an indefinite period at very low fuel cost, keeping the furnace above the dew point incidentally, until main flame heating is. required. Such main flame, B, Fig. 4, is propagated simply by admission of fuel through the tube 25' at a greater rate for the re quired duration under conventional thermostatic control, the pilot flame A being maintained continuously whenever the main flame is not present. Thus only two feeding rates for fuel are necessary once combustion or furnace operation is commenced.

The mainflame (B, Fig. 4) is fed by absorption of the greater rate fuel feeding of the burner through a wick disc .30. which is preferably a circular flexible piece, of sheet asbestos centrally perforated (without removal of material) and fitted over the tip 21 as at 3| in intimate contact therewith. The disc absorbs fuel from its underside which is in direct contact with the bottom of the pot hence with the cavity 26 and the absorbed fuel becomes gasified solely over the top side of the disc. No burning occurs at the outer edge of. the disc although exposed. A heat retaining-and air directing metal ring 32"having a central opening v33 concentric with the wick tip 2.1.lies over the wick disc 30 in spaced relation thereto, being supported by the pot portion 3 of the burner through the intermediary of the margin of the asbestos disc 30. The weight of the metal ring .assists in holding the relatively flexible disc 30 in shape, i.e., generally conforming to the bottom of the pot.

' Ihecontrol cabinet I I, Fig. 1, has a readily removable .top and frontcover section .35 which enables access to the controls including an .air gate .36 pivoted to the blower casing l as at 31 across the air inlet opening 12 to variably restrict it as will be described.

.The principal parts of the fuel control, as schematically illustrated in Fig. 2, are obtainable at the present time as a complete unit, the easing for which is indicated at 40 in Fig. 1. chamber 42, Fig. 2, of the unit has the usual valving, not shown, for incoming fuel through a line 25. vA safety latch, indicated by handle and trip 44 is usually provided to close off the fuel .iine by the float valve until such time as the furnace is to be used. The fuel from the float chamberflows to'a metering valve 145 shown as a plunger with a restricted cross passage 46 and main or'high fuel service cross passage 41, the

A .float shown, having inlet and outlet ports in registration with the restricted passage 46 in the illustrated lowered position of the plunger and with the high fuel passage 41 in a raised position (not shown). The plunger is biased upwardly by a suitable spring 48 against a bimetallic actuator 50 at a shoulder 49 on the plunger. The acutator normally holds the valve plunger in the lowfuel position in which shown.

Closing of a main or service line switch 5! (usually located separate from the furnace control cabinet) connects the usual service line current to the primary winding 53 of a step-down transformer 54, thereby charging the secondary winding 55 connected to a room thermostat 56, as clearly shown. A thermostatic limit switch .51 is usually provided in the bonnet of the furnace in series with the room thermostat. Otherwise a jumper is used as at 58.

Assuming the pilot flame A is already burning at the ceramic tip 21, Fig. 4, and that the'thermostat 55 is calling for heat, the low voltage in the secondary line portion 59 nowheats a resistance element Gil therein, hence the bimetallic actuator 56, releasing the metering valve plunger upwardly against a suitable stop such as a high-fuellimiting adjustment screw 6|. A corresponding low fuel adjustment screw 62 is represented as limiting the downward valve-operating movement of the actuator arm.

As the operating arm of the actuator 50 raises to enable the high fuel adjustment-of the metering valve (thereby admitting enough fuel to the feed tube 25 to charge the large wick disc 30), said arm closes a switch 65 in a main service line loop connection 66 which includes the motor 10, causing high speed operationof the blower.

While the flame in the burner pot 3 is relatively low, still burning at the ceramic tip 21, a correspondingly low rate of air supply should be admitted to the burner chamber through the pipe I4, distributor chamber !5, etc. Such regulation of air volume at low heat is the principal improvement hereof in the otherwise standard electrical control installation intended to be illustrated by Fig. 2.

For the purpose just indicated I connect a variable resistance unit 10 between one side of the service feed line and the motor III, as through a service line branch H leading to a portion of the loop 66. The unit 10, or at least its adjusting knob or lever, is located outside the cabinet 1 as on one of its end walls so that the resistance is adjustable with the cover 35 in place. The selector arm 12 of the resistance unit can thus adjust the motor speed from very low to its full or nearly the full speed at which it operates when the switch .65 is closed and independently of all parts of the control system exclusive of the master switch 51. p 7

During the fullor nearly full line voltage operation of the blower motor In at the start of high fla-me'burner operation the volume .of air admitted to the burner pot is controlled by adjusting the air gate 36. After the air and the fuel have been properly mated for high flame operation and that operation hasbeen discontinued the proper amount of air for the pilot flame is obtained by adjusting the speed of the motor by means of the variable resistance-unit 10.. It is evident from Figs. 3 and that-heat radi ated by the pilot flame A maintains the not a, ring 32 and annular top plate or ring 16 fairly hot; and, as soon as highf-uel :is admitted by the valve 45, soakinethe asbestos wick 30.. that flame will commence to be propagated over the latter. The flame grows vertically at first in a rapidly whirling cone or pencil as air from the distributor openings 20 circulates in the pot in a descending cyclonic stream pouring toward the center as deflected by the ring 32 into supporting contact with the flame and rising therewith around the vertical central axis of the pot. The oncoming air maintains the annular top plate or ring IS, the pot walls and ring 32 relatively cool or normally below the glow point. At the same time the air is preheated by contact with the metal walls for maintaining efficient combustion. As the high flame attains the diameter as indicated at B below the plate or ring 16 the top of it spreads out into a whorl over the curved annular plate or ring 16 and continues at even height until the room thermostat is satisfied and returns the system to pilot-flame operation as already described.

Because the flame B burns cleanly and only off the main face of the wick disc 30 (not at the edges as usual with oil wicks) the wick does not become charred. The heat is sufiicient to burn out all impurities hence the wick does not become clogged by oil residue.

The same thing may be said for the pilot wick tip 21. Being of ceramic material it is efiicient in absorbing oil; does not become coated with carbon no matter how long the pilot flame is kept burning, and it is unaffected by the intense heat of the main or high flame.

The burner is entirely safe in operation without requiring manual attention once put into service as described. As long as the pilot flame is maintained there can be no unburned gases gen- V erated at the burner. Should the pilot flame become accidentally extinguished from any cause the motor ill will continue to operate at low speed thus purging the furnace of any unburned gases and cooling down the metal surfaces and any residual carbon to below incandescence.

I claim:

1. In a pot type oil burner, a. metal body of bowl form' having a bottom cavity extending below its lower surface, a rigid porous wick lying in the cavity and extending above said lower surface, a flexible porous wick of disc-like form surrounding the rigid wick and in contact therewith, means for supplying air to support combustion at both wicks downwardly and inwardly within the body and means for supplying fuel to the cavity for absorption by both wicks.

2. In a pot type oil burner apparatus, a metal body of bowl form, flame supporting means including a fuel-absorptive wick at the bottom portion of the body concentric therewith and fuel with and having a continuous downwardly directed surface arranged to deflect such cyclonically moving air downwardly toward the wick for supporting combustion thereover.

3. The burner apparatus according to claim including means for charging the annular chamher with air in unidirectionally whirling condition and wherein the vanes extend outwardly from said inner wall generally unidirectionally and circumferentially at acute angles to associated portions of the wall for intercepting portions of the body of air circulating in the chamber.

4. The burner apparatus according to claim 2 wherein the vanes extend inwardly of said wall at acute angles to associated portions thereof and generally unidirectionally and circumferentially about the interior of said wall.

5. The burner apparatus according to claim 2 including means for charging the annular chamber with air in a unidirectionally whirling condition and the vanes extend outwardly at different distances from said wall incrementally therearound into intercepting relationship to such whirling air.

6. The burner apparatus according to claim 2 wherein the inner wall of the annular chamber is a sheet metal ring having the vanes lanced therefrom whereby they are readily adjustable to vary the effective area of the openings.

7. A pot type burner comprising a metal body of bowl form having a central bottom entrance means for fuel and a wick in the form of a disc absorptively associated therewith in contact with the bottom wall portion and exposed at its top face for supporting a flame thereover, said wick having a central upwardly protuberant pilotflame-supporting portion, a metal ring overlying the wick and extending inwardly thereover within the body near the bottom thereof, and means to introduce air into the body so that it flows over the top of the ring toward the open portion thereof whereby flame tends to be propagated at the main upper face of the wick rather than at its marginal edges.

HARRY E. MORLOCK.

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

UNITED STATES PATENTS Number Name Date 704,669 Tucker July 15, 1902 769,004 Margeson et al Aug. 30, 1904 1,362,192 Shafer Dec; 14, 1920 1,511,904 Nicholson Oct. 14, 1924 1,657,725 Schutz Jan. 31, 1928 1,711,140 DElia et al Apr. 30, 1929 1,969,371 Hawley Aug. 7, 1934 2,014,714 Bauer Sept. 17, 1935 2,117,356 Perry May 17, 1938 2,337,476 .Landon et al. Dec. 21, 1943 2,386,746 Hess Oct. 9, 1945

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