US2042942A

US2042942A - Safety burner

Info

Publication number: US2042942A
Authority: US
Publication date: 1936-06-02
Anticipated expiration: 1953-06-02

Description

3mi@ 2, 1936- H. l.. HlRscHLER SAFETY BURNER Filed April 15, 1952 .-I TTORNE Y.

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Patented June 2, 1936 UNTTED STATES PATENT OFFICE Y 2,042,942 SAFETY BURNER Horace L. Hirschler, San Francisco, Calif.

Application April 15, 1932, Serial No. 605,515

2 Claims.

My invention relates primarily to burners for use with gas and is especially concerned with mechanism adapted to be used with gas forthe safe combustion of such fuel.

7, An object of my invention is in general to improve gas burning and controlling mechanism.

Another object of my invention is to provide a gas burner particularly adapted for safe use with a water heater.

lo An additional object of my invention is to provide a gas burner provided with a pilot light and having means for disabling the main burner and the pilot burner in the event of gas failure.

A further object of my invention is to provide 'I5 means for preventing the operation of the pilot burner under adverse conditions.

The foregoing and other objects are attained in the embodiment of the invention shown in the drawing, in which Figure 1 is a cross section on a median plane of a. safety burner constructed in accordance with my invention.

Figure 2 is a cross section, the plane of which is indicated by the line 2-2 of Figure 1.

Figure 3 is a cross section showing in plan the safety burner of my invention installed in a water heater.

In its preferred form, the safety burner of my invention is inclusive of a hollow body having :11) a main gas inlet and a pilot gas inlet and provided with a main gas burner and a pilot gas burner, there being a main gas valve and a pilot gas valve for controlling communication between the body and the main and pilot burners respectively, together with a thermostat mounted on the body, and adapted to actuate a lever within the hollow body for controlling the operation of the main gas valve and the pilot gas valve.

In the form of my invention disclosed in the #i0 drawing, there is provided a hollow body 6 which preferably is of cast metal and which is provided with a main gas inlet 1 adapted to be connected to a suitable source of gas. The body 6 is likewise provided with a box 8 which is internally threaded to receive a nipple 9 on which a main gas burner I I is mounted. This burner comprises the usual Venturi section affording air inlet apertures I2 controlled by a rotatable shutter plate I3 and likewise includes a hollow head I4 with respect to which a top I6 is held in adjustable lspaced relationship by a stud I1 threadedly engaging a spider I8 cast integrally with the head I4. A variable annular opening I9 is thus provided for the emission of a gas and air mixture.

In order that gas flow'from the interior 2l (Cl. 15S-117.1)

of the hollow body 6 to the burner IIV can be controlled, I preferably mount a ball valve 22 to underlie a central passage 23 extending through the nipple 9 and ordinarily urge the ball from its seat by means of a coil spring 24 not only abutting the ball 22 but likewise abutting a burner tip 26 fixed in the end of the nipple 9. To limit the range of movement of the ball 2, the body 6 is provided with a boss 3| through which a stud 32 passes to form an abutment for the ball. A packing gland 33 or other closure prevents the escape of gas from the interior 2| to the atmosphere.

In order that the ame issuing from the burner head I4 can be extinguished and re-ignited as desired, I preferably provide a pilot burner. To this end the body 6 is provided with a pilot gas inlet 34 connected to a suitable source of gas and communicating by means of a passage 36 with an annular passage-38 within -a disc 3l. passage 38 extends past a seat 39 to radial openings 4I in a plug 42 likewise provided with a l peripheral channel 43. This channel opens onto a bore 44 in an extension 46 of the body 6 and communicates through a small hole 4l with a chamber 48 into which a pilot burner tube 49 is inserted.

Within the tube 49 is a thimble 5| having an n aperture 52 therein to provide for the issuance of a jet of gas which mixes with air aspirated thereby through openings 53 in the tube 49. The mixed air and gas passes through the tube 49 and issues from a burner opening 54 adjacent the far end thereof. The flame extending from the opening 54 is in sufficiently close proximity to the opening I9 to ignite the gas and air mixture issuing therefrom whenever such a mixture flows.

So that no combustible material may issue from opening I9 in the event the flame from the tube 49 is extinguished, I preferably provide a safety thermostat comprising generally an outer tube 56 which is held in adjusted position within a boss 51 on the body 6 by a jam nut 58. The upper end of the tube 56 is preferably closed by a plate 59 and is surrounded by a shield 6I of high temperature material. Within the tube 56 is a rod 62 having a coefficient of expansion materially diierent than that of the tube 56, so that upon variations in temperature of the tube 56 and the rod 62 relative movement between them occurs. This relative movement is made use of to control the issuance of combustible from the opening I9.

To this end the lower end of the rod 62 is brought approximately to a point and bears upon a resilient lever 63 mounted within the hollow interior 2l of the body 6. The lever 63 at one end is provided with a nearly circular but slightly elongated aperture overlying the ball valve 22, and intermediate the ball valve and the point of contact of the rod 62 the lever 63 is olset, as at 64, to provide a bearing against a fulcrum 66. The fulcrum is preferably adjustable and is comprised of a stud 61 screwed into the body 6 and carrying at its inner end an upstanding pin piercing the lever 63 and forming a guide therefor.

Because of this mechanism, when the ame from the opening 54 is extinguished, the thermostat promptly cools and the relative motion between the tube 56 and the rod 62 produced thereby causes the lever 63 to rock on its fulcrum 66 to urge the ball valve 22 into closed position against the inferior urging in the opposite direction of the spring 23. It is therefore impossible for combustible material to issue from the opening I9 if there is no flame at the opening 54.

To interrupt the issuance of combustible from the opening 54 in the event that there is no ame present at that point, I preferably extend the lever 63 to overlie and abut a plunger 68 guided within the plug 42 and at its lower end adapted to abut against the seat 39 to prevent flow thereby.` Thus when the valve 22 is urged toward closed position, the plunger 68 is likewise urged to closed .position and prevents the issuance of combustible from the' aperture 54.

In order, however, that combustible can again be caused to issue from the opening 54 for reignition and for further operation of the mechanism, I provide means for opening the passage past the seat 39 independently of the thermostat 62. To this end there extends into the passage 38 a screw 69 ngaging a threaded ring 1| seated in the body 6, and maintaining in compression a packing washer 12 interposed between the ring 1l and the member 31, a packing 13 interposed between the member 31 and the plug 42, as well as a packing washer 14 interposed between the plug 42 and the body 6. The character of these various packing washersis such that leakage from the body 6 is entirely prevented.

The screw 69 is rotated by an elongated lever 16 engaged therewith, so that upon actuation of the lever and consequent rotation of the screw 69, an extension 11 on the screw is urged axially into abutment with the member 68 and.dislodges it from its seat 39, thereby permitting gas to ow. This movement by the member 68 is partially resisted by the lever 63, but since this lever is resilient the member 68 can be opened sufliciently to permit a ow of gas to the pilot burner. When the pilot burner has again been ignited, the temperature of the thermostat increases, the pressure against the lever 3 is relieved, and under the urgency of the spring 23 the ball valve 22 is again unseated and the member 68 is again permitted to remain in open position; thereupon the main burner can again operate normally.

After the mechanism has once been shut down as previously described, the fuel is customarily reignited by an attendant and in order that the mechanism will again be conditioned to shut down automatically should the pilot flame for any cause be extinguished, I preferably mount the mechanism as shown in Figure 3. In this environment the entire mechanism is mountedy within-a housing 8| in which there is an openlng.82 through which access to the mechanism can be obtained. A door 83 is designed in one position to close the opening, and is hlngedly mounted as at 84 on the housing 8|. On the door 83, I preferably provide an elongated extension 86 which, when the door is in open position, is entirely clear of the path of the lever 16, so that the lever can be moved from run position away from the member 68 as shown at A in Figure 3, to start position as shown at B in Figure 3, wherein the member 6B is held from its seat 39. When, after the pilot light has been re-ignited,v the door 83 is again closed, if the lever 16 has not previously been moved from start position to run position, the extension 86 on the door during the closing movement thereof engages the lever 16 and moves it from start position to run position, thereby resetting the mechanism for further automatic operation.

If desired, the extension 86 can be omitted, in

which event the door 83 abuts the end of the lever 16 and cannot be fully closed until the lever is moved to its run position. To render the lever especially noticeable it can be provided with an enlarged and preferably brightly colored knob 81.

I claim:

1 A safety burner comprising a hollow body, a main gas burner mounted on said body and receiving gas therefrom, a pilot gas burner, a main valve within said body to control flow to said main burner, a pilot valve within said body to control flow to said pilot burner, a resilient lever within said body operable to actuate said valves, a thermostat on said body responsive to said pilot burner operable to actuate said lever,

and means on said body to operate said pilot valve adapted to be connected to a source of gas, a main gas burner mounted on and reeciving gas from said body, a main gas valve to control flow from said body to said main burner, a pilot gas burnei mounted on and receiving gas from said body, a pilot gas valve to control flow to said pilot burner, a fulcrum within said body, a resilient lever bearing on said fulcrum and` operable to actuate said main valve and said pilot valve, a thermostat mounted on said body and operable to actuate said lever, and means on said body to actuate said pilot valve independently of said thermostat.

HORACE L. HIRSCHLER.