US1794531A - Valve structure - Google Patents

Description

March 3, 1933. R. E. NEWELL I 1,794,531

VALVE STRUCTURE Original Filed Dec. 2, 1921 Patented Mar. 3, 1931 UNITED STATES ROBERT E. nEwnLL, or IRWIN, PENNSYLVANIA- VALVE STRUCTURE;

Original application filed December 2, 1927, Serial No. 237,170. Divided and this application iiled April 23, 1930. Serial No. 446,571. Y i

My invention relates to valve structures, and more particularly to means for control ling the flow of gaseous fuel to burners for water heaters, etc., and is a division of my application Serial N 0. 237,170.

In gas heaters for water, as in the case of domestic water heaters, it is common .practice to provide a main supply of gas to the burner for effecting actual heating of the Water and an auxiliary supply of gasfor a pilot flame, which will burn continuously or will ignite gas from the main supply each time such main supply is turned on as by a thermostatically-controlled valve. In such devices there is commonly no means for automatically controlling the supply of gas for the pilot flame nor, for automatically shutting off the main flow of gas in case the pilot flame should become extinguished. To provide a pilot flame, it is usual to supply a small by-pass for gas from the supply line to the burner, and, due to the very small size of the orifice required, such by-pass frequently becomes clogged, particularly where the gas contains foreign matter. 7

One object of my invention is to provide means for automatically shutting off the supply of all gas to the burner in case the flame or pilot becomes extinguished.

Another object of'my inventionis-to provide means for automatically controlling the supply of gas to the pilot flame, so that such flame may be maintained at a predetermined volume.

Another object of my invention is to provide an improved form of thermostat element that will not oxidize or deteriorate in the intense heat of the burner flame.

Still another object of my invention is to simplify and improve generally the structure and operation of fluid fuel burner devices.

One form which my invention may take is shown in the accompanying drawing, wherein Figure 1 is an elevational view of heating apis a sectional view, on an enlarged scale, of oneof the control valves of Fig. 1, andFig. 3 is a perspective view of the protecting sleeve for the thermal element of Fig. 2.

1 The invention is shown as employed in convalve casing 8.

paratus equipped with my invention; Fig. 2,

nection with a domestic water heater struc ture comprising a storage tank 4, heating coils 5, a burner 6, and a thermostaticallycontrolled valve 7 for normally controlling the main flow of gas to the burner in accord- I ance with the temperature of the water within the tank 4. These parts may be of various well-known forms.

My invention resides more especially in the provision of an auxiliary valve control devicewhereby-a supply of gas for a pilot flame is automatically maintained at a predetermined rate, and whereby the gas, both the auxiliary supply for the pilot flame and the main supply, are automatically cut off in case the flames become extinguished. The control apparatus above referred to includes a valve casing 8 having valve seats 9 and 10, with a space or chamber between them, and cover plates or castings l1 and 12. The casing 8 is provided with an inlet 13 through which the main gas supply enters from the thermostatically-controlled valve 7 and with an outlet 14 that communicates with the burner 6. A cover plate 11 is provided with an inlet 15 through which gas for the pilot flame may flow from a supply line 15a that has connection with the mam supply line 7a in advance of the thermostat 7.

Valve discs 16 and 17 co-operate with the seats 9 and 10 respectively. The valve disc 16 is loosely connected to a stem 18, which stem is slidably supported in a boss 19 of the The outer end of the stem 18 loosely engages with the valve 17. A spring 20 urges the valve 16 to its seat and, acting through the stem 18, urges the valve 17 from its seat. Normally the valve 18 will be closed and gas for the burner 6 will flow from the primary valve 7, through the inlet 13, past the valve 17,.and through the outlet 14.. A set screw 16a has threaded engagement with the valve 16, and abuts against the stem 18, so that such valve can be adjusted with respect to the stem and the valve 17.

A thermostatic element 21, which may be in the form of a copper or brass tube, is tapped into the cover plate 12 and extends above the burner 6. A push rod 22 of carbon or other non-expanding material is enclosed within the tube; 21, its outer end abutting against a screw plug 23 that is carried by the tube 21, and its inner end extending into a recess in the valve 17. Should the burner flame be extinguished, it will be seen that the tube 21 will cool and shrink, thus drawing the rod 22 inwardly-and pushing the valve 17 to its seat, thereby shutting off entirely the flow of gas to the burner.

m In cases where the main supply of gas from the valve 17 is reduced below the predetermined volume for the pilot flame, the temperature of the thermostat tube 21 will, of course, be reduced, causing it to contract to such extent as to move the valve 16 from its seat, thereby admitting suflicient gas past the valves 16 and 17 to maintain a normal pilot flame. Should the flame in the burner 6 become completely extinguished, the tube 21 will shrink to such extent as to completely close the valve 17 shutting off flow of gas both from the primary valve 7 and the pilot control valve 16. In order to againestablish flow of gas to the burner, a lighted match 25 will first be applied to the tube 21, ,causing it to quickly expand and allow the valve 17 tdopen under pressure of the spring 20, for the passage of gas which will be ignited by the matc A snug-fitting sleeve 25 is provided around the tube 21,. for the purpose of sealing it off from the air and consequently preventing oxid'ization thereof, through contact with the burner flame. This sleeve may be of chromium steel, which will resist oxidization'say up to 2000 F., or may be of various other suitable materials. The sleeve is thin enough to readily transmit heat to the co per tube, and may be removed and replaced liy taking off the cap 23 and sliding the sleeve of! the tube 21, if the cap 23 is of-considerably greator diameter than'the tube. However, if the cap is of small diameter,-asshown in Fig.

burner flame and serving to actuate saidvalve, and a s 'lit metallic sleeve closely embracing said t ermostat and operatively disconnected therefrom. 1

3. The combination with a fuel burner, of a fuel control valve therefor, a thermostat rod disposed in position to be acted upon by the burner flame and serving to actuate said valve, and a yieldable sleeve of heat-conductin material snugly fitting around the said 4. The combination with a fuel burner, of a fuel control valve therefor, a thermostat rod positioned to be acted upon by the burner flame and serving to actuate the valve, and a rotective heat-conducting member yieldab y engaging said rod and having direct heat conducting contact therewith during ex-.

pansion and contraction of the rod, the said member being interposed between the flame and the said rod.

In testimony whereof I, the said ROBERT E. NEWELL, have hereunto set my hand.

' ROBERT E. NEWELL.

2, the sleeve 25 can be slid 06 without disturbing the cap and, consequently, the setting of the thermostatthat is without disturbing the relative positions-of the tube 21 and-the rod, with consequent variation in adjustment of the valves 16. and. 17 relative tothe tube 21. Due to the relatively low co-efiicient of expansion, it is s lit its entire length to spring or yield so it will not bind on the tube 21v and prevent the normal expansion or contraction thereof. v

If the thermostat? is a, snap-acting or quick-acting one, which suddenly shuts ofi all gas to the main burner flame, it will be necessary to use an independent pilot burner which remains lighted, and to place the element 22 within a zone affected by the pilot flame but little afiected by the main burner flame.

Otherwise, the sudden extinguishing of the main burner would cause the pilot to go out "also, as the element 22'would not have time 5 to cool suflicientlv to open the" valvedisc 16'.

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