US2208884A - Safety ignition and control device for burners - Google Patents

Description

G. HERBSTER July 23, 1940.

SAFETY IGNITION AND CONTROL DEVICE FOR BURNERS Filed April 2, 1938 2 Sheets-Sheet 1 iflgfi INVENTOR. GEORGE HERBSTER Fig.1

Fig.2

ATTORNEY.

G. HERBSTER July 23, 1940.

SAFETY IGNITION AND CONTROL DEVICE FOR BURNERS Filed April 2, 1938 ZSheets-Sheet 2 warn INVENTOR.

GEORGE HERBSTER ATTORNEY.

Patented July 23, 1940 PATENT OFFICE SAFETY IGNITION AND CONTROL DEVICE FOR BURNER/S George Herbster, Cleveland, Ohio, assignmto John H. Leonard, trustee, Cleveland, Ohio Application April 2, 1938, Serial No. 199,661

6' Claims.

This invention is an improvement in an ignition and fuel control device for use in connection with a service burner and a pilot burner combination, and is a. continuation in part of my copending application, Serial No. 188,330, filed February 2, 1938.

One of the principal objects of the present invention is to provide an ignition and fluid fuel control device for a pilot burner and service burner combination, whereby (a) fuel must he admitted to the pilot burner before the ignition mechanism becomes operetive for igniting the pilot; (h) ignition of the pilot burner is s. condition precedent to the admission of fuel to the service burner; (c) admission of iuel to the serv ice burner renders the pilot burner ignition mechanism inoperative; and (d) extlnguishment oi the pilot burner stops the admission oi fuel to the service burner and automatically initiates c repetition of this cycle or" operation.

Another object is to provide e stop valve hoving s, thermostatically operated closure plug and a, movable seat and in which, after the valve plug is moved apredeterrcined amount by the thermoststic elements to an open position with re spect to the sect, it remains in the some rels ties to the sect, even though the valve plug is moved on additional distance in the opening direction by the thermostatic elements, so that, regardless of the amount of operation oi the thermostatic elements in the direction for opening the valve, the relation of the plug and seat does not exceed a. predetermined maximum separated position, and the amount of movement, and consequently the time for closing the valve, remains constant regardless of the position from which the plug starts toward closing position.

Other objects and advantages will become apparent from the following specification, wherein reference is made to the drawings, in which:

Figure 1 is a top plan view of a device embodying the principles of the present invention;

Figure 2 is a fragmentary sectional view taken on a plane indicated by the line 22 of Flg-' ure 1;

Figure 3 is 'a. fragmentary, sectional view, similar to Figure 2, showing the parts in different operating relation with respect to each other; and

Figure 4 is a diagrammatic illustration of the device showing the broad cooperative relation of the parts thereof.

For purposes of illustration, the present invention is described herein in connection with a gas service burner and gas pilot burner for use in ovens of domestic gas cooking ranges, its use in connection with other fluid fuels and apparatus being readily apparent from the exemplary disclosure. M" In the form illustrated, the device is shown in connection with e pilot burner l which is in firing relation to gas service oven burner 2, fuel being admitted to the pilot burner through a. suitable conduit 5 and to the service burner through a suitable conduit A needle valve 5, Fig. 3, is provided for regulating the amount of gas admitted to the pilot burner and the temperature regulator 6 is connected in the gas supply line =3 of the service burner so as regulate the admission of fuel to the service bur er.

The device of the present invention may corca, main outlet passage to which admits gas tothe service burner 22 through the pipe line t heretoiore described. Within the body it is a valve plug [16, the plug being mounted on a stem ll which is movable axially of the bore M. The plug is connected to the inner end of the stem ll by a pivot 98 which is disposed vertically for purposes later to he described.

Mounted within the bore M is a sleeve which is coaxial with the stem ll and is of greater internsl diameter than the external diameter of the stem. The outer circumferential well of the sleeve i9 is in sealed relation with the wall of the bore H but the sleeve is so mounted that it may be moved axially of the bore. The sleeve IQ is open at the end adjacent the plug l6 so as to afford a passage for gas from the inlet passage l2 into the sleeve. The sleeve has openings Isa for permitting gas to flow from the sleeve into the outlet passage IS. The inner end of the sleeve i9 is in the form of a seat 26 on which the valve plug I6 may seat for blocking the passage of gas through the sleeve from the inlet passage E2 to outlet passage IS.

The opposite end of the sleeve I9 is closed by an end wall, as shown, and the bore H is slightly longer than the sleeve IS. The bore II is deadended so that gas entrapped between the closed end of the sleeve 19 and the dead end of the bore H assists in yieldably resisting movement of the sleeve I9 toward the dead end of the bore, thus assisting in effecting proper seating of the plug l6 against the open end of the sleeve IS.

A follow-up or lost motion connection between the sleeve and valve plug is provided. This connection may comprise a -pin'22 which is connected to the stem I1 and is spaced from the l6 and maintains a constant opening between the plug-l6 and seat 20 of the sleeve regardless of the movement of the stem I! in the opening direction. Upon movement of the stem in the opposite direction, the plug needs to move only I a distance equal to the distance between the pin '22 and the adjacent end of the sleeve l9 to close the valve. Consequently if the stem is operated by a thermostatic lever, regardless of the amount of movement of the stem by the lever in the opening direction beyond a predetermined amount, the time required to close the valve remains constant, thus afiording a much more rapid shut-off. The valve, therefore, is .pro-

vided with a follow-up seat and a lost motion operative connection between the plug and the V follow-up seat. I I

As heretofore described, the valve plug it is connected to the stem H by an upright pivot I8.

Because of the pivotal connection between the plug l6 and the stem ii, the plug can adjust itself on the seat 20 and afford a better seating relation, and the sleeve is not subjected to any overbalanced weight of the plug it. If the pivot l8 were arranged horizontally, it is apparent that the plug it would hang downwardly at an angle to the stem and cause its lower portion to be nearer to the seat 20 of the sleeve than its upper portion. If, in this condition, the stem H were then moved to draw the plug it toward seating position, first the lower edge-of the plug it would engage the seat 20 and move the sleeve, without overcoming the overbalanced weight of the plug sufiiclently to cause it to seat about its entire periphery.

The body is provided also with a tubular portion 25 through which the stem I! extends to the outside of the body, suitable oil sealing grooves 26 being provided on the stem so, as to afiord an efiective" seal between the stem" I1 and the tubumaterial, is mounted on the yoke 3i.

lar portion 25 of the body.

Carried on the body in is a rigid tubular extension 21 and at the outer end of the extension 21 is a yoke having arms 29 to which are connected the ends of bi-metal thermostatic elements or levers 30, respectively. The opposite ends of the elements 30 are connected to the arms of a yoke 3|. A plug 32, of electrically insulating Mounted in the plug 32 is. a, metallic rod 33, one end of which, as indicated at 34, extends beyond the plug 32 and into closely spaced relation to the pilot burner I, the portion 34 providing a spark terminal for a high frequency spark mechanism, later to be described.

The rod 33 is connected to the stem i1, suitable electrical insulation 36 being interposed between the stem and rodso as to insulate the valve proper from the rod 33. The thermostatic levers 30 are arranged so that, upon heating, they move the valve plug it in the opening direction and upon cooling they return the valve plug to the closing position. If desired, a suitable springmay be utilized for the plug I6. I

In order to supply the high frequency spark. the rod 33 is connected by a suitable wire 31 to the high frequency terminal of a high frequency spark mechanism 28. 'I'hehigh frequency spark mechanism 38 is connected to a 110 volt alternating current circuit by the wire 39 and the wires 40 and 4|, a suitable switch being provided between the wires 40 and 45,, as better illustrated in Figure 3. 'As therein illustrated, the valve body is provided with a terminal plug 42 of electrical insulating material, the plug 42 being in sealed relation in a suitable uprightbore 63 in the valve body. The wires 40 and M extend through the'plug 82 and are provided with terminal contacts 44 and 65 which are exposed within thebore 43. Mounted within the bore 43 is a vertically reciprocable' plunger 46 which may be metal. At its upper' end, the plunger 46 carries a contactor 47 which is insulated from the plunger and is arranged to bridge between the contacts or terminals M and 45 and establish a circuit between the wires 40 and 4! when the plunger 46 is in a fully raised position in the bore 43.

The bore 83 is connected bya primary inlet duct 48 to the interior of the main valve body on the inlet side of the plug it so thatwhen the gas cock M is operated toadmit gas to the main valve through the passage i2, gas also passes through the primary inlet duct $8 to the under side of the plunger. The plungeris of such size that the pressure of the gas admitted to the in let side of the valve plug it is sumcient to lift the plunger to the ,top of the bore Q3 and thereby establish the circuit betweeutbe wires 4i! and 6!. The completion of this volt circuit in this manner renders the high frequency spark able duct 56, admits gas to the pilot burner l.

where it is ignited by the sparks.

In addition to the ducts as to st, inclusive,

a secondary inlet duct 5! is provided and connects the bore 63 with the main valve at the outlet side of the plug 56. For example, this con-' nection may be directly between the bore 53 and the outlet passage it of the main valve.

The secondary inlet duct 5! opens into the bore.

3 at a position above the uppermost position of the plunger '66. A secondary outlet duct 52 is connected with the bore 53 at a position such that it is blocked by the plunger 36 when the asareturnmeans- 7 plunger is in raised position, but is unblocked by the plunger when the plunger is in a lowered position wherein it blocks the duct 69. The secondary outlet duct 52 is connected with the duct '50 or is otherwise connected with the pilot.

As a result of this arrangement, when gas is admitted through the inlet passage 52 to the main valve while the main valve is closed, the plunger 46 is raised from the position illustrated in Figure-3 to the fully raised position illustrated in Figure 2. In this latter position, contact is made between the contact 61 and the terminal contacts 44 and t5, thus establishing a high frequency spark at the pilot burner. Concurrently with the establishment of this spark, gas is admitted to the pilot burner through the primary inlet duct 48, bore '33, primary outlet duct 69, and the duct 50. Thereupon the pilot burner is ignited and heats the thermostatic elements or aaoassc levers 30. These elements, when heated, move the main valve plug I! to open position, thus permitting gas to flow around the valve plug through the sleeve I! to the outlet passage II, and then to the service burner. However, when gas is admitted to the outlet passage ii in this manner, it also flows through the secondary inlet duct 5| into the bore 43 at a position above the plunger. Up to this time, the plunger N has been held in raised position, as illustrated in Figure 2, by the differential in fluid fuel pressure at opposite ends of the plunger 46. However, as a result of the admission of gas through the secondary inlet duct H, the gas pressure at opposite ends of the plunger 48 is substantially equalized, or the differential is so reduced that the plunger drops by its own weight to the position illustrated in Figure 3. When the plunger drops to this latter position, the primary outlet duct 49 is blocked but gas continues to flow to the pilot through the secondary inlet duct iii, the upper portion of the bores 83, the sec- Qndary outlet duct 52 and the duct 50.

In case the pilot is accidentally extinguished, the thermostatic elements to become unheated and the cycle above described is repeated im mediately upon seating of the plug it on the seat 20. Again, when the thermostats are heated for moving the main valve plug it to the open position, the plug opens a predetermined amount with respect to its seat 20, and thereafter the seat follows along with the plug and maintains a fixed distance therefrom as the plug continues to move in the opening direction. Consequently, if the pilot is extinguished for any reason, the valve plug 56 seats very promptly on the seat 2d and the thermostatic elements do not have to be permitted to cool completely to cause seating. As a result the valve cuts 0d the supply of gas to the main burner within two to four seconds after the pilot becomes extinguished and does not admit gas to the main burner again until the pilot has been relighted by the high frequency spark.

The above invention has been described herein in connection with gaseous fuel and in connection with a main valve body in which the various ducts and connections are provided directly in the valve body. It is apparent, however, that the various elements may be separately disposed and connected by suitable conduits, if desired.

Having thus described my invention, 1 claim:

1. The combination with a service burner, a pilot humor in igniting relation thereto, a main control valve for admitting fluid fuel to the service burner when the valve is open and for stopping the flow of fuel thereto when the valve is closed, thermally responsive means in heating relation to the pilot burner and operative when heated to open the main valve, said main valve tending to close when the thermally responsive means are unheated, of differential pressure operated ignition means rendered operative to ignite the pilot in response to a differential in pressure of fluid fuel at opposite sides of the main valve when the main valve is closed and rendered inoperative in response to substantial equalization of the pressure of fluid fuel at opposite sides of the main valve when the main valve is open.

2. The combination with a service burner, a pilot burner in firing relation thereto, a main control valve for admitting fluid fuel to the service burner when the valve is open and for stop ping the flow of fuel thereto when the valve is closed, mechanism including thermally responfuel admitted to the main valve, to render the second mechanism operative to ignite said pilot burner, and said last mentioned means being operative to render the second mechanism inoperative when themain valve is open.

3. A control and ignition device for a pilot burner and service burner combination compris ing a pilot burner, a main fluid fuel control valve having an inlet passage arranged for connection to a source of fluid fuel and anoulet pmage arranged for connection with a service burner, closure means in the valve body and operatively disposed between the passages, an auxiliary valve having a body with an upright bore therein, a plunger reciprocable in said bore, said auxiliary valve body having a primary inlet duct connecting with-said bore below the plunger and cornnected with the inlet side of the main valve whereby the plunger is raised by the pressure of the fuel admitted from the inlet side of the main valve through the primary inlet duct, said auxiliary valve body having a secondary inlet duct connecting with the bore above the uppermost limit or the plunger and connected with the outlet side of the main valve, said aurdliary valve body having a primary outlet duct positioned to be blocked by the plunger when the plunger is in a lowered position, said primary outlet duct being connected to the pilot burner, a secondary outlet duct connected with the pilot burner and connected with said bore above the plunger at a position to be blocked by the plunger when the plunger is raised to a predetermined position by the admission of fluid fuel through the primary inlet duct, thermally responsive means in heating relation to the pilot and operative to open the main valve when heated, said main valve tending to close when the thermally responsive means is unheated, means operable to ignite the pilot burner, means operated by the plunger when the plunger is in fully raised position to render the last named means operative.

4. In a pilot burner and service burner combination, a main fluid fuel control valve having an inlet passage for connection to a source of fluid fuel and an outlet passage for connection with a service burner, closure means operatively disposed between the passages, an auxiliary valve to the outlet passage, a primary outlet duct con- 'necting the cavity to the pilot burner, and a secondary outlet duct connecting the cavity and the pilot burner, auxiliary movable valve means in the cavity and normally blocking the passage of fluid fuel from the primary inlet duct to the outlet duct and operative, when the main. valve is closed, by fluid pressure admitted to the cavity through the primary, inlet-duct to move and admit gas to the primary outlet duct and to close the secondary outlet duct, and rendered operative when the main valve is opened and fluid is admitted through the secondary inlet duct to move and close the primary inlet duct and primary outlet duct and to connect the secondary outlet duct and the secondary inlet duct, ignition mechanism rendered operative for igniting the pilot burner when theauxiliary valve mcans is moved to posimain valve tending to close when the thermally responsive means are unheated.

5. A safety ignition system for a gas service burner of the type having a gas pilot in igniting relation to the service burner and wherein both the pilot and service burner are supplied with gas from a conduit having a manually controllable service valve; a normally closed stop valve in the conduit between the service valve and the service burner, a thermostat associated with the pilot and operatively connected to the stop valve in a manner to cause the stop valve to be opened consequent upon heating of the thermostat by the pilot flame, electrical ignition means in igniting relation to the pilot and including an electrical circuit and a switch for controlling the circuit to render the ignition means operative, and a pressure operable device normally tending to remain in an idle position and being movable into an active position to operate the switch, said device being subjected to gas pressure between the service valve and stop valve in a manner to move the device to active position when the service valve apes is opened and before the stop valve is opened,

and being subjected to counteracting pressure soas to actuate the switch in a manner to render the ignition means inoperative consequent upon opening of the stop valve;

6. A safety ignition system for a gas service burner of the type having a-gas pilot in igniting relation to the service burner and wherein both the pilot and service burner are supplied with gas from a conduit, having a manually controllable service valve; a normally closed stop valve in the conduit between the service valve and the service burner, a thermostat thermally associated with the pilot and connected mechanically to the stop' valve in a manner to open the stop valve consequent upon heating of the thermostat by the pilot flame, electrical ignition means arranged to establish a spark in igniting relation to the pilot and including a normally open electrical circuit and a switch adapted and arranged to close the circuit and a pressure operable device normally tending to remain in an idle position and being movable into an active position to close the switch, said device being subjected to gas pressure between the service valve and stopv'valve in a manner to move the device to active position when the service valve is opened and before the stop valve is opened, and being subjected to counteracting pressure so as to open the switch consequent upon opening of the stop valve.

GEORGE BS.

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