US2516504A

US2516504A - Safety control and pilot indicator

Info

Publication number: US2516504A
Authority: US
Publication date: 1950-07-25
Anticipated expiration: 1967-07-25

Description

y25, 1950 J. CERNY EIAL 2,516,504

A. SAFETY CONTROL AND PILOT INDICATOR MEANS FOR GAS BURNERS Filed Aug. 6, 1947 JOSEPH A. CERNY NOEL. B. GREEN Patented July 25, 1950 SAFETY CONTROL AND PILOT INDICATOR ,MEANS FOR GAS BURNERS Joseph A. Cerny, University Heights, and Noel B. Green, Willoughby Township, Lake County, Ohio, assignors, by mesne assignments, to Aniliated Gas Equipment, Inc., Cleveland, Ohio, a

corporation of Delaware Application August 6, 1S", Serial No. 766,546

3 Claims.

This invention relates to control means for gas burners, of the type wherein a main burner is served by automatic safety pilot means, ignition means under remote manual control being provided for the pilot means, and during pilot operation the burner operation being automatically responsive to a room thermostat or the like.

The principal object of this invention is to provide signal means, available to the operator of the ignition means, to indicate functioning of the pilot means, it being understood that the pilot means is located adjacent the burner in the combustion chamber thereof, and hence at least relatively invisible and inaccessible to the operator.

Further objects and advantages will be apparent from the following description taken in connection with the accompanying drawing, which is a conventionalized diagrammatic view showing pertinent parts of a burner control system embodying the invention, the parts appearing in cold or oil position.

with reference now to the drawing, A indicates the main gas burner to be controlled, and which is served by pilot mean thereadjacent and generally indicated at B; typically both burner and pilot means being located within a combustion chamber as conventionally indicated by the (Cl. 158-11'L1) to the starting stem 86.

broken line C-C in the drawing, remaining parts to be described being typically located outside the combustion chamber.

The burner A has gas supply by the line I subject to automatic valve means 50 and also the usual main gas shut-oil valve 53.

The pilot means B herein chosen for illustration is described in complete detail in our copending application, Serial No. 694,268, filed August 31, 1946; and includes a safety pilot stem 60 in igniting relation to the main burner A, a starting pilot stem 6 to which the pilot stem 60 is in relation to be ignited, and a thermal element ID in thermally responsive relation to both pilot stems 60 and 66.

Automatic switch means are provided, actuable by the thermal element It and consequently responsive topilot operation. More particularly, the switch means includes a contactor l3 arranged to provide a cold contact at 23 in absence of pilot flame and a hot contact at 24 in presence of pilot flame.

The starting stem 6 of the pilot has gas supply from the line I ahead of the shut-off valve 53 subject to a manual shut-oil valve 5|, and a spring-closed push button valve "V which is part Means such as ignition coil 40 are provided for ignition of gas at the starting pilot stem responsive to closing of the switch part 903 of the device D, by depression of its push button 903.

More particularly, as will be seen from the drawing, the energizing circuit of the ignition coil 40, which constitutes the starting circuit for the pilot means, includes a transformer 9| as energy source connection line IOI, the manual switch 908, line I02, line I03 including the ignition coil 40, the cold contact of the automatic thermally responsive switch of the pilot B. movable contactor l3, and return to transformer 9| by way of line I including the flexible connection from the contactor l3 as indicated in the drawing.

It will be apparent that gas thereto and ignition of such gas, at the starting stem 66, will be had by depression of the push button 908; and further that upon energlzation of the thermal element III by starting pilotfiame, the circuit of the ignition coil 40 will be automatically broken to de-energize the coil'independent of the push button, by breaking of the cold contact at 23.

Gas supply to the safety pilot'stem ill is from the pilot gas shut-off valve Si, by way of line I05 independently past the push button valve 90V but subject to an automatic valve 83 eflective in the line I05. The valve" is spring closed but has opening actuation by the thermal element ing pilot. Thus, once the safety pilot stem is operating it will continue in operation after release of the push button until its gas is cut off, by closure of the pilot gas valve ill, or by outage of its own flame and consequent automatic closure of the automatic valve 83.

For gas supply to the main burner A, its gas valve 5|! includes an actuator 50a in a running circuit from the transformer s I as indicated in the drawing, which circuit includes, line I It the hot contactor 24 of the thermally responsive switch, line I" including the usual room thermostat or the like 92 the valve actuator "a, and return of a manually operated combined valve and line I; the arrangement being such that the main gas valve is opened only when the circuit is complete. Thus, upon pilot outage and consequent breaking of the hot contact at 24, the main burner gaswlll be automatically shut off; whereas during pilot operation with hot-contact made at 24, the'main burner will have gas at call of heat by the room thermostat 92, and immediate ignition of such gas from the safety or running pilot stem 0.

What has thus far been described precedes the invention of this application, and is disclosed more fully in our above dentified copending application. The drawing herein approximately follows Fig. 12 therein, with similar reference characters where practical.

According to the invention of this application, means are provided for apprising the operator of the push button device D, of condition at the relatively inaccessible pilot B.

To such end a signal device, such as an indicating light L, is arranged in a signal circuit including, from the transformer 9|, the line Ill, the manual switch means 90S, signal device BIL, lines I08 and iii, hot contact 24 of the switch of the pilot means 13, moving contact l3, and return line "II to the transformer.

Operation of the signal device will therefore include the following: to initiate operation of the pilot B manual depression of the push button 903 will be as before, but establishment of the pilot flame will be indicated to the operator by energization of the signal light. Thus the signal indicates that the push button may be released, the flame having been established, or lack of signal indicates failure of gas supply or of the pilot as by ignition coil burnout; whereas with-V out the signal the operator would be left at least in temporary doubt as to presence of the flame.

After energization of the signal means, release of the push button both de-energizes the signal means terminates gas to the starting pilot 66 by closure of its valve 90V.

Pilot operation may be instantly indicated to the operator by the signal, at any time by depression of the push button, since only if the pilot is on will the thermal element It be energized to make its hot contact at 24 in the signal circuit.

Both on and off timing of the pilot may be checked by the operator by means of the signal. The on check is bad by noting the lapsed time between depression of the push button and energizing of the signal light. The off check is had by depression of the push button to energize the signal when the pilot is in operation, then cutting on pilot gas at the shut-oil valve 5| and noting lapsed time until the signal is de-energized. As will be appreciated by one familiar with the art, such timing checks are valuable indications of proper functioning of automatic pilots; and this invention provides therefor without removal or direct observation of the pilot as has heretofore been necessary for the purpose.

Still further, both checks may be made not only without disturbing the installation but without any danger of explosion, by closure of the main gas shut-oil! valve 53 before performing the tests.

It is to be noted that the arrangement of the invention is such that a burnout of the signal device does not otherwise affect operation of the starting and running circuits or functioning of the parts therein.

While the manual switch is herein indicated as a single-throw, double-pole type, controlling the two otherwise independent circuits, it will 4 be apparent that other switch arrangements might be employed.

Likewise, whereas the signal device is indicated as of visual character and located at the push button'to form apart of the manual device assembly, if preferred the device might be of other character such as oral, and/or located elsewhere in its circuit, effectively available to the push button operator.

In general, the signal device with its novel circuit as herein disclosed is of great convenience and other advantage to the servicemen; both in testing the entire installation newly installed, or thereafter when a malfunction or non-function has occurred.

It may be observed that the control means of this invention involves three electrical circuits. First, is a starting circuit which includes the manual switch, the pilot ignition coil, and the cold contact of the pilot-responsive switch. Secondly, is a running circuit which includes the main gas valve, thethermostat, and the hot contact of the pilot-responsive switch. A third circuit also is involved, which third circuit includes the signal device, the manual switch of the starting circuit, and the hot contact of the running circuit. The third circuit is thus dependent for its completion to energize its signal device, upon contact at the manual switch of the starting circuit coincident with hot contact at the thermally responsive switch of the running circuit.

What is claimed is:

1.. In combination with a main gas burner, valve means arranged for control of gas supply thereto and including a valve actuator, pilot means arranged to provide an ignition flame for said burner, ignition means for said pilot means, manual switch means, thermally responsive means arranged to be energized by operation of said pilot means. automatic switch means arranged to have actuation by said thermally responsive means to provide a cold contact in absence of said flame and a hot contact in presence of said flame, said manual switch means, said ignition means, and said automatic cold contact, being arranged in a starting circuit, said valve actuator and said automatic hot contact being arranged in a running circuit signal means, and means providing a, signal circuit therefor including said manual switch means and said automatic switch hot contact, and excluding said ignition means, said cold contact and said valve actuator.

2. In combination with a, main gas burner, valve means arranged for control of gas supply thereto and including a valve actuator, safety pilotmeans disposed in igniting relation to said burner, starting pilot means disposed in igniting relation to said safety pilot means, ignition means for said starting pilot means, manual switch means, thermally responsive means arranged to be energized by operation of either of said pilot means, automatic switch means arranged for actuation by said thermally responsive means to provide a cold contact in absence of said flame and a hot contact in presence of said flame, means for providing a, starting circuit including said manual switch means, said ignition means, and said automatic cold contact, for energizing said ignition means, and means providing a running circuit including said valve actuator and said automatic hot contact, whereby gas supply to said burner is responsive to said ignition flame therefor: signal means, and means providing a signal circuit therefor including said 5 manual switch means and said automatic switch not contact.

3. In combination with a main gas burner, valve means arranged for control of gas supply thereto and including a valve actuator safety pilot means in igniting relation to said burner, starting pilot means in igniting relation to said safety pilot means, ignition means for said starting pilot means, thermally responsive means arranged to be energized by operation of either of said pilot means, safety pilot supply valve means responsive to said thermally responsive means, automatic switch means arranged to have actuation by said thermally responsive means to provide a cold contact in absence of pilot flame and a hot contact in presence of said flame, starting pilot supply valve means, manual means for coincidently opening said starting pilot valve means and energizing said ignition means, and means responsive to said thermally responsive means to deenergize said ignition means upon energization of said thermally responsive means: signal means, and signal circuit means associating said signal means with said manual means and with said hot contact to provide energization of said signal means on coincident operation of said manual means and energization of said pilot means.

JOSEPH A. CERNY.

NOEL B. GREEN.

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

UNITED STATES PATENTS Number Name Date 1,575,170 Knopp Mar. 2, 1926 2,077,297 Williams Apr. 13, 1937 2,078,576 Laghetto Apr. 27, 1937 2,192,632 Beam Mar. 5, 1940 2,200,908 Beggs May 14, 1940 2,238,890 Clark Apr. 22, 1941 2,238,892 Fanger Apr. 22, 1941