US2288937A - Stove - Google Patents

Description

July 7, 1942. J.. E. CHAMBERS' STOVE Filed Oct. 11, 1937 2 Sheets-Sheet l INVENTOR. fin/vfi Cimnasles,

ATTORNEYS.

July 7, 1942. J. E; CHAMBERS STOVE Filed Oct. 11. 1937 Sheets-Shut 2 ATTORNEYS.

Patented July 7, 1942 UNITED STATES PATENT OFFICE STOVE Jchn E. Chambers, Shelbyville, Ind. Application October 11, 1937, Serial No. 168,323

(c1. 12s-a9) 18 Claims.

In gas ranges employing a thermostatic control of oven temperature it is customary to provide a pilot burner and a main burner and to regulate the supply of gas to the latter by means of a, temperature-responsive valve. One difiiculty encountered in such an arrangement arises from the fact that the temperature-responsive valve, because of slow opening or slow or imperfect closing, will under some conditions pass gas at a rate insuflicient to maintain combustion at the ports of the main burner. To overcome this difliculty, it has been proposed to install around the temperature-responsive valve a by-pass which will provide gas-flow at the minimum rate required to insure maintenance of combustion, and to employ the temperature-responsive valve only to vary gas supply over a range above this minimum rate.

The by-pass arrangement just described is open to the objection that in order to insure against extinguishment of the flame in a main burner having sufiicient capacity to raise the oven to the maximum desired temperature within a satisfactorily short time, the minimum rate of gas flow provided by the by-pass is too high to be economical and, especially in the case of an insulated oven, too high in some instances to prevent oven temperature from rising unduly above the value at which it is desired to maintain it.

It is the purpose of my invention to overcome the difliculties above noted and to provide a gas burner which will operate at maximum efficiency when supplied with its full quota of gas but which will produce a stable flame at minimum rates of gas-flow considerably lower than any possible with safety in prior arrangements. A further object of my invention is to provide an arrangement in which gas leaking past a nearly closed temperature-responsive valve in quantity insufficient of itself to maintain combustion will nevertheless be burned and prevented from escaping. Still another object of my invention is to eliminate the necessity for a pilot burner as a separate element in association with a thermostaticall controlled main burner.

In carrying out my invention, I form the burner with two independent passages for the combustible mixture of gas and air, and I provide each of such passages with aseries of discharge orifices. The supply of gas to one of these passages is controlled by an automatic valve responsive to oven temperature, while the supply of gas to the other passage is fixed at the minimum rate necessary to maintain combustion at the orifices of that passage. The main gas passage,

" primary air.

or that associated with the automatic valve, has each of its discharge orifices arranged in igniting relationship to an orifice of the other passage, so that any gas escaping from the mainpassage orifices in quantity insufficient to maintain combustion will burn with the gas emerging from the orifices of the other passage.

The accompanying drawings illustrate my invention: Fig. 1 isa horizontal section through the oven of a gas range, showing my improved burner in place therein; Fig. 2 is a fragmental vertical section on the line 22 of Fig. 1; Fig. 3 is a vertical section on an enlarged scale on the section line 33 of Fig, 1; Fig. 4 is a plan view of a .modified form of burner; Fig. 5 is a vertical section on the line 55 of Fig. 4; Fig. 6 is a vertical section on the line 6-6 of Fig. 4; and Fig. 7 is a section on the'line 'l! of Fig. 5.

The oven l0 illustrated in the drawings has insulated walls H and a suitable door I 2. The burner, which is disposed in the oven a short distance above the floor thereof, is hollow and, in the arrangement shown in Figs. 1 to 3, substantially U-shaped in plan. The interior of the burner is divided into two passages l4 and I5 by a partition l6 which extends from one end of the burner to the other in spaced relation to the side walls thereof. Communicating with the passage I4, conveniently at the middle of the intermediate leg of the U-shaped burner, is a main mixture-suppl conduit l1 formed near its inlet end with a venturi l8 and provided with a conventional mixing valve IQ for the admission of A similar conduit 11', having a venturi I8 and mixing valve Iii, communicates with the gas passage I5 of the burner. The burner is provided with a series of discharge orifices 22 for the passage l4 and with a second set of discharge orifices 23 for the passage [5. Each orifice I5 is disposed adjacent an orifice M, and each such pair of adjacent orifices is desirably located at or near the bottom of a recess or port 2| provided in the burner above the partition l6.

Gas for the two mixture conduits I1 and I1 is supplied from a main gas line 25 and through two branches 26 and 21 to the mixing valves 19 and I9, respectively. In the branch 26, I provide an adjustable temperature-responsive valve 28 controlled by a temperature-responsive element 29 associated with the oven lit, and in the branch 21 I provide a manually controlled valve 30 adapted for adjustment to a fixed position controlling the minimum supply of gas to the burner. A main gas valve 3| located in the main supply line is employed to shut off the supply of gas to both branches 25 and 27.

In operation, the valve 3| is opened and the burner ignited, preferably at one or more ignition ports 33 provided in the burner at the point where the conduit l1 joins the passage l5. If the oven is cold at this time, the temperatureresponsive valve 28 will be open, and gas will be supplied through the conduits I1 and II to both passages I4 and I5. Gas from both such passages will pass through the openings 22. and 23 into the ports 2| and will emerge from each port, in effect, as a single stream. As the temperature of the oven approaches that for which the valve 28 is set, the temperature-responsive element 29 will operate to control the valve 28 in such a way as to maintain the desired oven temperature. As the valve 28 moves toward closed position under regulation by the temperature-responsive element 29, the amount of gas supplied to the passage M will be decreased and will eventually reach a point at which it would be insufiicient of itself to maintain combustion; but because all combustible material passed by the valve 28 emerges from the orifices 22 in proximity to the burning gas from the orifices 23, any small quantities of gas leaking past the valve 28 when nearly closed will be consumed. If the temperature-responsive ele- 'ment 29 completely closes the valve 28, the only gas received by the burner will be that supplied through the conduit IT to the passage l5. The valve 3|] is so adjusted that this amount of gas will burn with a very low flame which will cling to the walls of the port 2| and will be stable.

It is to be noted that the path traversed by the gas supplied through the valve 30, conduit Il', passage I5, and openings 23 is entirely independent of the path over which fiows the gas controlled by the temperature-responsive element 29. Because of this, the diameters of the openings 23, the cross-sectional area of the conduit II, the shape of the venturi I8, and the mixing valve I9 can be such as to provide for the most efficient burning of the minimum supply of gas and for a gas velocity sufficient to prevent back-firing, while the openings 22, conduit l1, venturi I8, and mixing valve I9 can be designed for most eflicient operation of the main gas supply.

In the modification of my invention illustrated in Figs. 4 to 7 inclusive the burner is of an elongated shape and is intended to extend transversely across the oven l3 preferably near the front end thereof. The burner comprises two elongated portions 4|] and 4|, the former having a longitudinally extending central opening in which the latter is received. If desired, the two portions 40 and 4| may be formed as parts of a single casting, being joined together by bridgelike members 42. The portion 48 is hollow to provide a mixture-passage 43 communicating with a mixture-supply conduit 44 which joins the portion 40 conveniently near its center. The portion 4| is likewise hollow to provide a passage 45 communicating with a mixture-supply conduit 45.

The side walls of the burner-portion 4|, as is clear from Fig. 6 converge upwardly to a relatively narrow top wall which is disposed below the upper surface of the burner portion 45 and in which I provide a row of discharge orifices 48. The main burner portion 45 is provided with discharge orifices 4}] along the sides of the central opening. To bring the orifices 49 as close as possible to the orifices 48, the central opening in the main burner-portion is constricted at a point near the top of the burner-portion 4| and the sides of the central opening diverge upwardly above such constriction. The mainburner discharge orifices 49 are located in such upwardly diverging side walls to discharge obliquely upward above the burner-portion 4|. Desirably, the orifices 49 along one side of the central opening in the main burner portion are staggered relatively to those along the opposite side to avoid impingement of the respective flames; and each of the orifices 43 in the burner portion 4| is disposed midway between two orifices 49 on opposite sides of the central opening.

Below the constricted portion of the central opening in the main burner-portion the side walls thereof diverge downwardly in spaced relation to the burner-portion 4| to provide passages 59 for the admission of secondary air.

In an arrangement such as that described, the mixture-supply conduits 44 and 45 may be brought outwardly through a side wall 53 of the oven where they are adapted to receive gas respectively from the conduits 25 and 2'! illustrated in Fig. 1. As, is clear from Fig. 4, the supply conduits 44 and 46 are enlarged beyond the side wall 53 of the oven to form chambers 54 each of which has an air-admission opening in its rear wall. The efiective area of each of these openings may be regulated by a disk 55 supported on the rear end of a screw 55 which is screw-threadedly mounted in the front wall of the associated chamber 54 and which has associated with it a lock nut 51. Conveniently, the outer ends of the two conduits 44 and 45 are offset vertically so that both screws 56 are accessible from the front of the stove.

The passage 43 need not be continuous around the central opening. As is clear from the drawing, such passage is interrupted by a solid bridgemember 60 located centrally of the burner on the front side thereof. Conveniently, the upper surface of this bridge is located below the top of the burner-portion 4| so that it will be possible to observe, through a sight-opening (not shown) in the front wall of the oven, whether or not there are flames above the orifices 43 of the inner burner-portion 4|.

The construction illustrated in Figs. 4 to 7 possesses all the advantages of that shown in Figs. 1 to 3. It has the further advantage, however, that only one half as many auxiliary orifices 48 are necessary to have one closely associated with each of the main orifices 49. I can thus increase the difference between the minimum and maximum capacities of the burner.

I claim as my invention:

1. In a gas range, a burner comprising a hollow member, a longitudinal partition within said hollow member dividing its interior into two independent mixture passages, said burner being provided exteriorly with a row of recesses substantially co-planar with said partition, each of said recesses communicating independently with said passages, supply conduits of different crosssectional areas for the respective gas passages, and a temperature-responsive valve associated with the supply conduit of larger cross-sectional area.

3, A gas burner having a series of burner ports and two independent mixture supply passages independently communicating with each of said ports through restricted openings, the openings through which one passage communicates with said ports being smaller than the openings through which the other passage communicates with said ports.

4. A gas burner having a series of burner ports and two independent mixture supply passages independently communicating with each of said ports through restricted openings.

5. A gas burner having a series of burner ports and two independent mixture supply passages independently communicating with each of said ports.

6. A gas burner having two independent mixture supply passages each having a series of discharge orifi-ces, said orifices being arranged in pairs with the two orifices of each pair communicating respectively with said two passages, and a common port for each such pair of orifices.

7. A gas burner, comprising a U-shaped tube, a partition extending from one end of said tube to the other and dividing the interior of the tube into two independent mixture passages, a U-shaped row of burner ports co-planar with said partition and each communicating independently with said two passages, and two supply conduits communicating respectively with said two passages at points located on opposite sides of the intermediate leg of said U-shaped burner.

8. The invention set forth in claim 7 with the addition of means for independently controlling the supply of gas to each of said supply conduits, the control means associated with one conduit being temperature-responsive.

9. A gas burner provided with a supply passage having a row of upwardly directed discharge orifices, said burner also being provided with a second supply passage having two rows of discharge orifices located on opposite sides of said first passage and discharging generally toward each other over the orifices therein, and means for independently supplying gas to said two passages, said means including a temperature-responsive valve controlling the supply of gas to the second passage.

10. A gas burner provided with a supply passage having a row of upwardly directed discharge orifices, said burner also being provided with a second supply passage having two rows of discharge orifices located on opposite sides of said first passage and discharging generally toward each other over the orifices therein, and means for independently supplying gas to said two passages, said means including a temperacure-responsive valve controlling the supply of gas to one of said passages.

11. A gas burner provided with a supply passage having a row of upwardly directed discharge orifices, said burner also being provided with a second supply passage having two rows of discharge orifices located on opposite sides of said first passage and discharging generally toward each other over the orifices therein, and means for independently supplying gas to said two passages.

12. A gas burner, comprising a hollow elongated central portion, a hollow outer portion embracing said central portion but spaced therefrom, and conduits for supplying gas independently to the interiors of said hollow burner-portions, said central burner-portion being provided with a row of upwardly directed discharge orifices and said outer burner-portion being provided With two rows of discharge orifices located on opposite sides of and discharging generally toward each other over the row of orifices in said central burner-portion, the orifices of said outer portion being inclined upwardly toward said central portion to discharge obliquely thereover.

13. A gas burner, comprising a hollow elonated central portion, a hollow outer portion embracing said central portion but spaced therefrom, and conduits for supplying gas independently to the interiors of said hollow burner-portions, said central burner-portion being provided with a row of upwardly directed discharge orifices and said outer burner-portion being provided with two rows of discharge orifices located on opposite sides of and discharging generally toward each other over the row of orifices in said central burner-portion.

14. A gas burner having a main mixture supply passage and a smaller auxiliary mixture supply passage independent of each other, each of said passages being provided with a series of discharge orifices, the orifices in said auxiliary passage being directed generally toward the orifices of the main passage whereby any gas emerging from the orifices of the main passage will be ignited by the flames from the orifices of the auxiliary passage.

15. The invention set forth in claim 14 with the addition of means for independently controlling the supply of gas to each of said passages, the control means associated with said main passage being temperatureresponsive.

16. The invention set forth in claim 14 with the addition that the orifices associated with said auxiliary passage are smaller than those associated with the main passage, and temperatureresponsive means controlling the sup-ply of gas to the main passage.

17. The invention set forth in claim 14 with the addition that the orifices associated with said auxiliary passage are smaller than those associated with the main passage.

18. The invention set forth in claim 14 with the addition that the orifices associated with said auxiliary passage are smaller than those associated with the main passage. and supply conduits for said two passages respectively, the supply conduit -for the auxiliary passage being smaller in cross-sectional area than the other supply conduit.

JOHN E. CHAMBERS.

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