US2402011A - Pilot valve construction - Google Patents

Description

" June 1 1, 1946.

F. E. BEEBE P ILOT VALVE CONSTRUCTION Filed May 19, 1945 ll mu l Sheets-Sheet l INVENTOR.

Heine/ck A? 55555 June 11,1946.

F. E. BEEBE PILOT VALVE CONSTRUCTION Filed May 19, 1945 2 Sheets-Sheet 2 INVENTOR. FQEOE/CK [7 5.6555

, d /I YSW Patented June 11, 1946 UNITED STATE S PATENT OFFICE PILOT VALVE CONSTRUCTION Fredrick E. Beebe, VVillowick, Ohio Application May 19, 1945, Serial No. 594,779

1 Claim. 1

The invention relates to a novel and improved valve construction and more particularly to a novel and improved arrangement of a pilot valve and a main valve in a gaseous or other fluid combustion system.

An object of the invention is to provide a novel, improved, and extremely simple and efiicient structure wherein the main valve and pilot valve are associated in a unitary housing.

Further objects and advantages will be pparent from a study of the following specification, in conjunction with the accompanying drawings, in which Fig. 1 is a side elevation of a valve construction embodying my invention;

Fig. 2 is a sectional view taken on of Fig, 1;

Fig. 3 is a sectional view taken on the line 3-3 of Fig. 2;

Fig. 4 is a sectional view taken on the line 4-4 of Fig. 2;

Fig. 5 is a somewhat enlarged view, in side elevation, with parts broken away and in section, showing internal details of the pilot burner;

Fig. 6 is a sectional view taken on the line 6-5 of Fig. 5, and

Fig. 7 is a side elevational view from the position of the line 'i'! of Fig. 1.

The valve arrangement herein shown is of the so-called safety pilot type-wherein fuel gas flows from the supply source to the main burner in the combustion chamber only when the pilot flame is burning, and wherein the gas flow both to the main burner and to the pilot burner is cut off if for any reason the pilot flame is accidentally or intentionally extinguished. To accomplish this purpose a thermostatic device is disposed adjacent to the pilot burner, and is responsive to ignition thereof, so as to cause opening of the valve permitting flow to the main burner only when the temperature of the thermostatic element exceeds the critical operating point. This mode of operation is conventional, but the present structure whereby the operation is efiected is distinctly novel'and materially improved.

Referring now to the drawings, illustrating an embodiment of the invention, there is shown a chambered valve housing I i having an inlet port 52 in communication with the gas supply (not shown), an outlet port H3 in communication with the main burner (not shown), and a pilot burner [4 associated with a bi-metallic thermostatic element l5. Progressive change in temperature of element l5 past a thermal critical point produces the line 2- 2 appropriate opening or closing of valves in the housing interior, as will now be described.

The housing comprises a hollow body portion I! provided with a central partition wall l8 which defines within thebody a pair of generally similar chambers here termed, for identification, an upper or inlet chamber [9 in communication with the inlet port I2, and a lower or outlet chamber 20 in communication with the outlet port l3. An aperture 23 in wall l8 permits gas flow from chamber l9 to chamber 20 under the control of a pair of valves A and B arranged in series. .In the embodiment hereshown the valves seat by peripheral contact of resilient facing disks 24 with the respective upper and lower edge portions of aperture 23. Obviously both valves must be unseated to permit gas flow to outlet port 13 and thence to the main burner. The manner of operation of the valves will be described here'- inaiter.

The upper wall of chamber H1 is closed by a flexible metallic diaphragm 26 whichis imperiorate except for an aperture at its center which permits passage therethrough of the stem 21 of valve A. A gas tight seal is secured by the cooperating packing nuts 28 and 29. Diaphragm 26 is retained by a screw cap 30 which is centrally perforated at 3! to allow free movement of a plunger 32 in which the valve stem 21 is adjustably retained. It will be apparent that in assembling the apparatus, the normal unflexed position of diaphragm 26 compels a positive seating of valve A on wall [8. The seat is leakproof, but the valve is readily cracked by slight outward tension on plunger 32. Plunger 32 carries a manipulating nut 33 circumferentially slotted at 34. The slot 34 is straddled by the bifurcated fingers 35 of thermostatic element l5, expansion of which effects outward movement of plunger 32 to produce unseating of valve A. The plunger may also be manipulated manually to produce the same effect.

Elements in and adjacent to the outlet chamber 20 which are similar to those just described in the last preceding paragraph are identified by similar reference numerals with the suflix b appended thereto.

The novel arrangement of the pilot burner supply'passage will now be described.

The partition wall I8 is provided with a drilled passage 40 extending from central aperture 23 outwardly to, and communicating with, the pilot burner l4. As long as valve A is open, even a slight amount, gas from inlet chamber l9 flows to aperture 23 and thence through passage 40 to J an extension thereof 40a in the pilot burner, regardless of whether valve B is open or shut,

As heretofore indicated, when the system is not in operation and the thermostatic element is at room temperature or not materially above room temperature, both valves A and B are normally closed. However when the system is in operation, and the pilot is burning, thermostatic elements l increase in temperature and rapidly reach a critical point where they urge their respective elements outwardly so as to open valves A and B, To start operation from a cold system however, valve A must be manuallyunseated by lifting nut 33 to permit gas to flow to the pilot. The pilot is then ignited while holding valve A open. The tongues liia afiixecl one to eachleg of element l5, are directly subjected to the pilot flame, and causesaid legs to quickly heat up.

One such leg maintains valve A open, and the other opens valve B to'themain burner which is thereuponignited by the pilot flame.

I have provided automatically releasable abutment means which may be used to maintain nut 3.3 in raised position until the heat of the pilot flame takes effect, as described immediately above, after which said abutment drops out of operative engagement with nut 33. Said abutment (Fig. 17) consists of a lever 38 freely movable on a pivot ,pin .39 afiixed to cap on the valve body, andnormally .biased to drop by gravity to the full line position, When starting the burner and pilot devices from a cold condition, the nut 33 is lifted, and the free .end of lever 38 is swung up and -inserted thereunder in the dotted .line position, where it is retained by the nut under the influence of the inward bias of thermal element l5. When the pilot is lighted, and the thermal element 45 heats sufiiciently to reverse said bias and tends to move the .nut 3.3 outwardly, the lever .38 drops again to the 'full line position, and operation proceeds as ,previously-described.

Gas .flow between outlet port [3 and the main burner may be .normallysubjected to further con- .trol, for example by a room thermostat (not shown) which intermittently steps or starts flow of fuel to the main burner. The pilot burner insures flow of fuel through the main valves herein shown and described, and through said valves to the other valve .(not shown) controlled by the room thermostat.

Should the pilot valve for any reason be accidentally or unintentionallyextinguished, element .15 will cool and both the valves A and ,B will 4 almost immediately close, thereby rendering the system safe and fool proof until it is again started manually, as already described.

Figs. 5 and 6 illustrate in somewhat greater detail the structure of the pilot valve which is fed through a passage 40a constituting a continuation of the passage 40 in partition wall 18. A nipple 5i], integral with the valve body, has a hexagonal external contour in cross-section, and an'inner sleeve 5| has a-pressed fit thereon. An outer sleeve 52, coaxial with the inner sleeve and the nipple, has a threaded connection on the shoulder 53at the base of the nipple. The outer sleeve has therein a circumferentially spaced series of perforations 5d. The device operates as follows. When gas flows upwardly (Fig. 5) through passage 46a a flow of primary air is inspired through apertures 54, and upwardly through the segmental clearance channels 55 (Fig. 6) between nipple 5.0 and sleeve .5 I- A'secondary air current .flows upwardly throu h the annular passage 56 between sleeves 5i .and 152. The volume of gas is controlled by an adjusting screw 51 (Fig. 1) in the valve housing. An efficient gas-air mixture, and an adequate secondary air supply is assured by the structure just described.

What I claim is:

Structure of the character described comprising a hollow valve "housing, a partition disposed transversely within said housing whereby to divide said housing into two chambers, an inlet port in one chamber for communicatin with a gas supply source, an outlet port inthe other chamber for communicating with main burner means, said'partition being provided with an aperture therethro-ugh to permit gas flow from one chamber to the other, said partition being further provided with a passageway extending laterally within said partition from said aperture to the exterior of said housing, a pilot burner communicating with the outer extremity of said passageway, a pair of valves in said housing disposed in the path of gas flow, one valve of said pair on the inlet side of said aperture and the other valve of said pair on the outlet side of said aperture whereby opening of the valve on said inlet side feeds said pilot burner and opening of both said valves feeds said main burner, and thermostat means responsive to the flame of said pilot burner, and operatively associated with said pair f valves, for controlling the operation thereof.

FREDRICK E. BEEBE.

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