US747244A - Automatic gas-burner. - Google Patents

Description

PATENTED DEC. 15, 1903.

W. (LDUDLEY.

AUTOMATIC (44s BURNER.

APPLICATION FILED AUG. 2, 1901.

N0 MODEL.

m: Mmms puns co, Pnmoumm waivz-w'ro rrnn dra ns iatented December 15, 1903.

WALTER J. DUDLEY, OF BANGOR, MAINE.

ATOMATIC GAS BURNER.

SPECIFICATION forming part of Letters Patent No. 747,244, dated December 15, 1903.

Application filed August 2,1901. Serial No. 70,686. (No model.)

To all whom it may concern:

Be it known that I, WALTER J. DUDLEY, a citizen of the United States, residing at Ban gor, in the county of Penobscot and State of Maine, have invented a new and useful Automatic Gas-Burner, of which the following is a specification.

My invention relates to an improved automatic or safety-burner for preventing the continued escape of unlighted gas.

The device constituting this invention consists in part in a tube arranged to have one end heated by the gas-flame, while the other or distant end is curved and arranged to normally close the gas-inlet of the burner. This tube is filled with a fluid easily expansible or vaporizable by heat, such expansion creating a stress in the tube and causing the curved portion to expand or assume a flatter curve,andtherebyuncoverthegas-inlet. The principle upon which this tube is constructed and operates is that of the ordinary Bourdon tube used in pressure-gages and some metallic thermometers, and this tube will be hereinafter referred to asa Bourdon tube. An arrangement whereby the tube and its contained fluid are heated not by the direct flame impinging thereon, but by means of a solid projection or pin secured to the tube and projecting into proximity to the flame, thus forming a conduit for the heat, is also a part of my invention,the object being to avoid excessive heating of the fluid. A method of filling the tube with a fluid of small expansive coefficient at the temperatures to which it is exposed in use with the exception of. a portion nearest the source of heat, which is filled with ahighlyexpansible fluid, forms a part of myinvention,the object being to avoid the excessive strains consequent upon the heating of a comparatively large body of easily-expansible fluid, as the burner becomes heated throughout when lighted for long periods.

A form of my burner is shown in the accompanying drawings, in Which-- Figure 1 is a vertical section taken through the center of a burner. Fig. 2 is a horizontal section on line W X; and Fig. 3 is a similar section on line Y Z, Fig. 1. a

The base A of the burner is threaded at a to screw onto the fixture and expanded above into a cup at, which is shouldered at 0, to receive and support the annular plate B, to which latter are attached the automatic devices controlling the admission of gas to the burner-pillar b, said pillar being secured to plate B, as shown. The upper edge of cup a may be spun over plate 13 to make a tight joint. A heating-chamber, shown as a tubular ring (1, supported on an upright tube D, encircles the burner-pillar nearits upper end, anda heat-conductor, such as a pin d secured (preferably brazed) to said tubular ring, projects upward opposite one end of the gasslit 0 in burner-tip O in such manner that the free end of said pin is continuously heated by the gas-flame, and heat is thus conducted from the flame to the tubular ring (1, the amount conducted depending on the diameter and length of pin d and its position relative to the gas-flame. The bore of tubular ring (1 is continuous with that of tube D. Tube D is inserted at (1 into an elbow d, which latter passes through and is secured to plate B. A thin flat elastic Bourdon tube F, curved, as shown, to conform somewhat to the shape of the interior circumference of cup or, is secured at one end atf to elbow 01, while its free end is embedded in a flat-faced block f, the cavity of tube f being continuous with that of elbow d, tube D, and tubular ring d. The whole series of tube-cavities is filled with fluid, of which at least the portion contained in ring 61 must be easily expansible or vapo rizable by heat, but it is preferable to have the remaining fluid practically non-expansible at temperatures to which it is exposed in use. the fluid is hermetically sealed within the tube-cavities.

The face of block f when the burner is cold rests against an arm I, closing a gas-portql in said arm and constituting a valve controlling the supply of gas to the burner-pillar. Arm I projects from a hollow plug H, said plug being closed at the lower end and with the upper end opening into the cavity of the burnerpillar b, as shown, and port '1; is continuous with the hollow of said plug. Plug H is shouldered and riveted at 71 into the center hole of plate B, and gas entering pillar b must first pass through port 1' in arm I and the cavity of plug H. Plug H is secured to plate B so After filling the tubes as to turn stiffly and is provided with aslot -h, so that it can be turned by a screw-driver fluid as will damage the burner.

and the relation of arm I to block f (or the valve to its seat) be easily adjusteda matter of practical importance.

In a properly-adjusted burner when cold tube F will assume the position of Fig. 2, resting against arm I and closing port 7;, and in this position gas cannot pass to the burnertip if turned on by the usual thumb-cock.

To light the burner, a flame, of a match usually, must be placed beneath tubular ring (1, which will expand or volatilize the contained fluid and createa pressure in tube F, and when this pressure has sufficiently increased tube F yields by expanding or straightening its curvature, as shown in Fig. 3, thereby moving block f away from arm I and uncovering port 2', thus admitting gas to the burner-pillar b and tip 0, where it becomes ignited by the same flame that heated ring (1. The continued heating of ring 01 by the heat conducted to it by pin 01 keeps up sufficient pressure to retain tube F expanded and the gas-port 'i open. If The flame becomes extinguished from any cause, the resiliency of tube F will cause it to assume the normal position, asin Fig. 2, as the tube cools off and the pressure of the contained fluid diminishes, thereby bringing block f over port z'and shuttingoff the gas from the burner-tip.

I find it very easy to so proportion pin (1 that the amount of heat conveyed by it to tubular ring 01 is just enough to keep said ring heated to the proper degree and no more, as a balance is struck between the amount of heat received and that radiated by the ring and its immediate connections, which is practically constant. This plan of heating a fluidcontaining chamber indirectly is of greatimportance, as it is otherwise impossible to at times avoid such excessive overheating of the This overheating is especially liable to occur when the gas is turned 'low down or when it is being blown about by a draft. In this latter case the flame is liable to be blown directly upon the fluid-containing chamber and either rupture it or so strain the movable member that the burner becomes useless. The plan of heating through a conduit of limited conducting capacity avoids all such danger.

It will be noticed on inspecting Fig. 3 that when tube F has expanded to fully uncover port '5 the outer curve of said tube osculates quite closely with the interior circumference of cup at. This is so arranged for the purpose of preventing tube F from exceeding its elastic limit in expanding under pressure, so that it will surely return to the position of Fig. 2 and close port'iwhen the burner is cold.

I prefer to use a steam-pressure in operating the burner, choosing for this purpose a liquid of low boiling-point, such as alcohol or naphtha, and the tube-cavities may be completely filled therewith with good results; but it is preferable to fill only ring (1 with such a liquid and to fill the remaining spaces with a liquid not boiling at the temperatures to which it is exposed in use, as after burningfor a considerable time the entire burner may become heated, and it is desirable to avoid the excessive pressure that would be caused thereby if all the tube-cavities were filled with a pressure-generating fluid.

It is of course necessary to use two liquids that will not mix-such as naphtha and water, for instance.

As liquids of low boiling-points usually are of low specific gravities, there is no liability of the two liquids changing places in use, as the lighter and more volatile fluid will naturally remain at the top; but evenif the burner be inverted, as in transport, the two liquids will not change places, as the tubes are so small that adhesion and cohesion are stronger than gravity in this case.

It is evident that if the tubes are completely filled with a liquid of high expansive coefiicient 'at temperatures below the boiling-point of such liquid the'burner can be operated without the generation of a steam-pressure.

In using the combination of the two fluids in the way described I do not wish to confine my claims to the particular form of burner vherein shown and described. Other forms of automatic burner can be adapted to use this principle, such as that class in which the valvecontrolling device contains a flexible diaphragm which is pressed in and out by the pressure generated in a miniature boiler or heating-chamber near the gas-flame.

I am aware that a curved sealed tube containing an expansible fluid and operating a valve when subjected to varying temperatures has been previously used in connection with steam-traps, and therefore I do not broadly claim the adaptation of the Bourdon tube to operating-valves, but

What I do claim is- 1. In an automatic gas-burner; the combination'with a valve-seat; of a Bourdon tube carrying a Valve to cooperate with said valveseat; a fluid contained in said tube; a'heating-chamber communicating with said tube but at some distance therefrom, and a different fluid contained in said heating-chamber, substantially as described.

2. In an automatic gas-burner; the combination with a valve-seat; of a Bourdon tube carrying a valve to-cooperate with said val veseat; a fluid contained in said tube; a heating-chamber communicating with said tube and containing a different fluid; and a heatconductor close to the burner-orifice and leading to said heating-chamber.

8. The combination with a valve-seat; of a Bourdon tube carrying a valve to cooperate with said seat; a fluid contained in said tube and means for conducting the heat of the flame to said fluid; and means for adjusting the position of said valve-seat relative to the valve, substantially as described.

4. The combination with a valve-seat; of a Bourdon tube carrying a valve to cooperate with said seat; a heating-chamber communieating with said tube but at some distance therefrom; a fluid of relatively high coeflicient of expansion contained-in said heatingchamber; and a fluid of relatively low coefficient of expansion contained in said tube, substantially as described.

5. The combination with avalve-seat; ofa Bourdon tube carrying a valve to cooperate with said seat; means for exerting pressure within said tube; and -a stop substantiallyconforming to the curvature of said tube,substantially as described.

6. The combination withaburnerofavalve for closing the gas passage thereof and a flexible curved tube containing a fluid for actuating said valve and arranged to operate when the burner is heated and thereby maintain the valve in an open position until the burner cools, substantially as described.

7. The'combination with aburner ofavalve for closing the gas-passage thereof and a flexible curved tube situated within the burner and containing a fluid for actuating said valve and arranged to operate when the burner is heated and thereby maintain the valve in an open position until the burner cools, substantially as described.

8. The combination withaburnerofavalve for closing the gasrpassage thereof and a flexible curved tube containing an expansive fluid for actuating said valve and arranged to operate when the burner is heated and there: by maintain the valve in an open position until the burner cools, substantially as described.

9. A burner containing means for automatically preventing the flow of gas therethrough when the flame is extinguished, said means including, as the actuating element thereof, a flexible curved tube containing a fluid the pressure of which is increased when the burner is heated, substantially as described.

10. The combination with a burner of a thermally-actuated valve controlling or closing device therefor, and said device including a flexible curved tube having therein an expansible fluid and means, exposed to the atmosphere, for conducting a limited amount of heat to said valve-controlling device so as to avoid rupture of the parts when expansion occurs, substantially as described.

11. The combination with a burner having a space or chamber in its body portion, a curved flexible tube containing an expansible fluid disposed within said chamber, a valve also disposed within said chamber and arranged to be actuated by said tube, and a second tube in communication with said flexible tube at one end and adapted to receive heat from the flame of the burner at the other end, substantially as described.

12. The combination with a burner having a space or chamber in its body portion, a curved flexible tube containing an expansible fluid disposed within said chamber, a valve and an oscillatory hollow block communicating with the burner-passage and carrying a valve-seat also disposed within said chamber and arranged to be actuated by said tube, and a second tube in communication with said flexible tube at one end and adapted to receive heat from the flame of the burner at the other end, substantially as described.

WALTER J. DUDLEY.

Images