US2659426A - Oil burner with heat responsive fuel cutoff - Google Patents

Description

NOV. 17, 1953 w, RQWELL 2,659,426

OIL. BURNER WITH HEAT RESPONSIVE FUEL CUTOFF Filed May 12, 1950 2 Sheet-Sheet 1 1 l I g 0 I o o l o o o 0 o O a 0 U. 0 0 o o o o 0 a Q o o o o a o o 5 s o o no 0 o o o o o o o o 0 a Q 0 0 0 0 0 o 0 o 0 o o o o 6 0 a a 0 IL/ o o o O o o o 0 j o c o f a 4 4 o o o o o o. o o fi o o o o 0 0 O O Q 0 0 0 0 f f 0 O Q 0 l0 o o o o 0 0 L l L 5 l8 f r-L 2 Z 4 36 4 5 5' 5 IIIIIIIIIIIIIIIIIIIIIIL Patented Nov. 17, 1953 OIL BURNER WITH HEAT RESPONSIVE FUEL CUTOFF William G. Rowell,

Scully Signal Quincy, Mass., Company, Cambridge, luass., a

assignor to corporation of Massachusetts Application May 12, 1950, Serial No. 161,518

6 Claims.

This invention relates to a safety control system for use with oil burners. It is particularly concerned with the provision of an oil supply system for a burner in which is included a valve so located and constructed that it will close automatically when the temperature in the immediate proximity of the valve has risen to a predetermined degree.

The purpose of the invention is to prevent the spreading of an oil fire caused by overflow of oil from a conventional oil burner. In the ordinary case, the oil supplied to the burner will come from a constant level oil source, but the invention is effective to shut ofi the oil supply egardless of the nature of the supply source whenever there is a burning overflow. This result is accomplished by the inclusion in the oil supply line to the burner of a special type of valve located where it will be promptly actuated to cut E the oil supply whenever it is subjected to a high temperature such as that produced by the overflow of burning oil from the burner base.

The valve as shown in the present disclosure and used in this safety system has been designed particularly for use with range oil burners and pot burners which are in general use throughout the country. As the valve has been arranged with these burners in a new and novel manner, the invention comprises the combination of a burner, a carbon leg and a valve in an arrangement which will act as a safeguard against fire from overflowing burners.

Reference will be made hereinafter to a range burner in combination with the other parts of the invention but it will be understood that other burners, such as pot burners, utilizing liquid fuel supplied from a constant level tank are to be considered the equivalent of the range burners.

In the operation of a conventional range burner, the oil is turned on by manual operation of a valve. The oil flows from the supply tank to the base of the burner where it saturates a wick. As the fuel used with these burners is of low volatility, being an oil usually referred to in the trade as No. 2 oil or kerosene, the burner ignites slowly. However, after the Wick is ignited and the temperature of the shells gradually rises, the oil vaporizes to a greater degree and combustion improves. In the meanwhile, the adjustment of the valve is cut back as the amount of oil needed during normal operation is less than is necessary for initial ignition. If the operator fails to reduce the oil supply at the proper time, or if the valve is inadvertently opened too wide during normal operation, the

oil reaching the base Will not be completely vaporized and burned. Instead it will rise in the base and overflow to create a dangerous fire of burning oil in the base of the fire box below the burner or on the floor if the burner is not in a confined area. Such fires are particularly hazardous as they are continuously fed by a steady The invention also includes a tell-tale for indicating to the user that the valve has functioned. This is desirable since there is no way of resetting the valve from the exterior due to its packless construction.

The invention also includes a replacement unit which may be inserted in the valve body so that the valve may then be ready for further service.

Studies have been made to determine the maximum temperatures that exist in positions immediately under burners during normal operation. These studies have also shown that immediately produced by the overflow of burning oil.

' are not shown.

Fig. 2 is an enlarged cross section of one form of valve.

Fig. 3 is a cross section of a modified form of valve.

Fig. 4 is a cross section of another form of valve 11 which the valve housing must be removed from the fuel line for replacement of the thermally operable valve unit.

Fig. is an enlarged cross section on the line 5-5 of Fig. 4.

Fig. 6.is a cross section of still another form of the valve.

Fig. '7 is Fig. 8 is a vertical Fig. '1.

Fig. 9 is a view in elevation of a modification of the device as applied to a pot burner.

Referring to Fig. 1, there are shown two range burners 2 and 4 of the conventional perforated combustion tube type positioned within a firebox 6 with a chimney connection, not shown. These burners, however, of housing and might be supported in any convenient position. All that is required in such cases is that suitable draft conditions are for proper combustion.

A constant level oil supply, not shown, is fed by a pipe 8 to a pair of valves 10 which control individually the oil flowing through pipes l2 and 14 to the burner The burner bases are circular to forated combustion concentric vaporizing initially flows and in which it is vaporized for combustion thereabove. An automatically controlled temperature valve which may assume any of the specific forms d" ein or their equivalent is connected to pipe carbon leg 22 which base It. A similar valve with pipe l4 and base l8 but these are not illustrated as they would be simply duplicates of parts 20 and 22.

Th burners are supported respectively by posts 24 and 26 which are carried by the mountlng plates 28 and 3D. The rang burners thus described and including the carbon legs and supports are conventional. The valve 21!, however, is so located with respect to the base It and the carbon leg 20 that it will be in a position to be immediately influenced by any rise in temperature caused by overflowing burning oil. The rise in temperature thus created will cause the valve 20 to close automatically, thereby stopping the flow of oil to the base l5 even though the valve Ill is open. The valve 28 and all of the other valve forms hereinafter disclosed are of a type which when once closed will not re-open of themselves and therefore may be considered of the irreversible type.

In Fig. 2 is shown one form of valve construction which comprises a valve body 32 having threaded extensions on each end as at 34 and 36 for connection with pipe [2 and carbon leg 22 respectively. The inlet and outlet passages 38 and 48 are separated by a restricted area 42 which has about its periphery a valve seat 44.

Screwed into a suitable threaded opening 48 in the bottom of the body is a threaded plug 48 having a flange 50 which may be gripped by pliers or a wrench. The interior of plug 48 has a bore 52 in which is positioned a compressed spring 54. A ball valve 56 is secured at the upper end of bore 52 by fusible material 58.

when the temperature surrounding the body 32 rises to a predetermined degree, fusible material 58 will melt, freeing ball valve 56 so that compressed spring 54 will drive the ball valve forcibly against the corresponding valve seat 44 thereby effectively closing the valve to cut of! L-Janl sunnlv (if 011 to the burner.

a cross section of another modification. section on the line 8--8 of receive the permight be within any other type present bases l6 and I8 respectively. A

and carbon leg connect In the preferred construction, ball valve 56 will have a depending stem which extends downwardly through the coils of spring 54 to eliminate any possibility of the ball valve slipping sideways from its position on top of spring 54 during the closing operation.

It will be observed that there is a tell-tale 88 secured to the under side of flange 50 by fusible material 62 which is designed to melt at approximately the same temperature as fusible material 58. Thus, whenever the valve closes, fusible materlal 62 will also have melted to enable tell-tale 60 to fall away from its normal position. In this way, after the burner has gone out, the user by feeling with his finger on the bottom of plug 48 can tell at once whether or not the valve has functioned. If the tell-tale is still present, the valve is open; if the tell-tale is gone, the operator knowsrthat the valve is closed. He then shuts .ofivalve l0 and removes plug 48. In so dowithdrawn also and a new plug 48 including the ball valve held in position by fusible material 58 and a tell-tale may then be inserted in valve body 32 thereby putting the fuel line in condition for further operation of the. burners under the control of valves III.

A modified valve construction is shown in Fig. 3. This valve comprises a body 64 with the inlet and outlet legs 66 and 68 positioned at right This construction may facilitate certain types of installations. The valve seat and valve and the supportin plug and other related parts have all been numbered to correspond with the similar parts previously referred to in Fla. 2 and further descri tion is therefore not necessary. The valve f on: in the same manner as the valve of Fig. 2. The tell-tale 80 may elthu' be of non-fusible material secured by fusible material 62 or it may be composed in its entirety of fusible material which will flow away when the valve is actuated Another form of valve is shown in Fig. 4. In this construction it is necessary to remove the valve body from the supply line when it become! necessary to insert a new valve unit. This valve comprises a body 18 having a hexagonal portion at 12 for easy ginning with a wrench or pliers. The threaded ends 14 and 16 with the supply line I! and the carbon leg 12. not shown, which is in connection with pipe II. The body 10 has a conical valve seat 80 but thb The body is threaded interlorlv at 82 to receive a threaded plug 84 which, cut away. on opposite sides at 86 and 88 to permit fluid to pass thereby. The end of plug 84 is slotted at I to receive a screwdriver for propel adjustment. The interior of plug 84 has a bore 82 large enough to receive a valve pin 84 and fusible material 98 positioned between the bore and the valve pin. 0n the end of the valve pin is a valve "and a. spring I under compousion urges valve 28 in the direction of valve seat 80. As soon as the temperature surrounding body 10 rises to a predetermined degree, tulible material 96 will melt freeing valve pin 04 enabling spring l0. to drive valve 94 forcibly against seat It, thereby closing the valve. A telltale I02 is provided in the form of a ring cl fusible material set in a circumferential M around body 10. when the temperature rial sufllciently to melt fimible material 88, the tolltale It! will also have melted so that by viral or manual inspection the user can tell the valve is open or closed.

If the valve has closed and the fire has gone out, the user will then close valve I 0 and will uncouple valve body 70 from pipes I2 and 18. Plug 84 is then unscrewed from the body and valve 98 removed. A new plug and valve may then be inserted in the body and a strip of fusible material wrapped around the body to act as a new tell-tale I82. Valve body i then reinserted in the fuel supply line and the burner is again ready for operation.

In the construction shown in Fig. 6, this arrangement provides a body I04 having an inlet leg I06 and an outlet leg I08 arranged parallel but oifset. This construction in certain cases facilitates the attachment to the carbon leg under the burner. The construction of the automatic valve is substantially the same as that shown in Figs. 2 and 3 and the parts have therefore been correspondingly numbered and reference to the previous description of these parts will sufiice to explain the operation of the construction of Fig. 6.

The construction shown in Figs. 7 and 8 constitutes a simplified form of the basic construction generally disclosed in Fig. 4. The valve body II 0 has a threaded extension H2 at one end, adapted to be connected with a fuel supply line in the usual manner. The extension H4 at the other end of the body is shown with a smooth exterior for connection with the carbon leg or a member leading to the carbon leg by any suitable connecting means. Extension II4 if preferred may be threaded if this will facilitate connection.

A bore H6, extending throughout the length of the valve body, has an entrance at II8, a main channel I and an outlet I22. A circular valve seat I24 is adapted to receive a conical valve I26 which is normally in open position. This valve has a valve stem I28 which extends through a somewhat larger circular opening I30 in a fiat cross bar I32, the ends of which rest against a shoulder I34 at the inner end of the entrance II8.

Valve stem I28 is held in fixed position in relation with cross bar I 32 by means of a small quantity of fusible material I36. A spring I 38 is maintained in compressed condition between cross bar I32 and the head of valve I26.

The length of cross bar I32 is slightly greater than the diameter of entrance H8 and the ends of the cross bar are so formed that when the cross bar has been forced downwardly to the position shown against seat I34, it will resist removal.

Thus when fusible material I36 is melted by a rise in the temperature, valve stem I28 will be freed of cross bar I 32 and valve I 26 will be driven by the spring I38 firmly against valve seat I24. thereby to close the valve.

Cross bar I32 i of such transverse dimensions as to leave passages I40 and I42 on either side thereof which passages provide adequate space for liquid fiow while the valve is open.

A tell-tale I44 in the form of a circular ring is positioned in a circumferential groove extending about the valve body. This tell-tale is made of fusible material designed to melt at the time the valve is actuated by fusing of material I36. Thus, by visual inspection or by feeling the valve body, the operator may be advised whether the valve is still open or has closed. If it has closed then it may be removed from the liquid supply line to be replaced by a new unit.

Fig. 9 is a view in elevation of a modification of the invention as applied to a typical pot burner I45. The burner consists, as is usual, .01 a vaporizing troughor receptacle I46 having extending upwardly therefrom a perforated side wall I41, which together with the vaporizing trough forms a combustion chamber. Extending from the side of the vaporizing trough I46 is a fuel supply line I48 having an enlarged portion I49 and having a portion I50 thereof extending beneath the burner. Positioned in this portion of the supply line is the irreversibly operable, high temperature responsive, automatically closing valve I 5|, this valve being similar to the valves described in the various modifications discussed above. It is apparent that burning oil overflowing from the pot burner will cause the valve to function in the manner described above in order to interrupt the fiow of oil to the pot burner.

The specific temperatures at which the valves disclosed herein are caused to operate under different conditions of use are not set forth as it will be understood that the temperature will vary for specific situations. However, studies have shown that the temperature continuously prevailing in reasonably close proximity to the under side of a range burner base when the burner is in full operation will be of the order of 350 degrees Fahrenheit. The temperature will, of course, vary inversely with the distance from the under side of the base. When oil overflows from the base and is ignited on the bottom of the stove or on the floor immediately below the burner, the temperature in the vicinity of the used. In general, it may far that a fusing point of satisfactory be said from tests thus about 361 will produce typical installation.

scope of the invention I claim: 1. In combination, an oil burner of the vaporizing type including a vaporizing receptacle and having a perforated sidewall extending upwardly base 01- said burner, said valve being directly and responsively subject to heat from burning oil overflowing irom said burner to 'niterrlm the flow of oil to said receptacle.

2. In combination, an oil humor or "th tim having a vaporizing trough in the base thereof and a perforated tube extending upwardly irom said trough to form therewith a combustion chamber. an oil supply line including a carbon leg communicating with said trough to supply 011 thereto and depending directly from the base of said burner, and an irreversibly operable high temperature responsive automatically closing, valve in the oil supplyjllne leading to saidcarbon leg and located directly underneath the base or said burner, said valvebeing directly responsive to heat from burning oil that-has overflowedrrom said burner to interrupt the 011 how to said trough.

3. In combination, an oil burner of the pot burner type having a vaporizing receptacle therein and a perforated tube extending upwardly from said receptacle and adapted to be supplied with oil'trom a substantially constant level source and subject to overflowing under improper conditions of operation, an oil supply line'including a portion communicating with said vaporizing receptacle and a second portion positioned directly underneath the base of said'burner, and an irreversibly operable high temperature re- 'sponsive automatically closing valve positioned in said line directly underneaththebaseot said burner, said valve being directly responsive to heat (rom burning oil that has overflowed from said burner to interrupt the oil flow to said receptacle.

4. The combination set forth in claim 1 and including means positioned adjacent said valve to indicate the response or said valve to said overflowing burning oil.

5. The combination set forth in claim 1 and including fusibly releasable operating means connected to said valve.

6. The combination including iusibly releasable valve operating means connected to said valve and indicating meanspositioned adjacent said valve to indicate the response of said valve to said overflowing burning oil.

WILLIAM G. HOWELL.

References Cited in the file of this patent UNITED STATES PATENTS

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