US1747589A - Pilot-controlled valve - Google Patents

Description

Feb. 18, 1930. L. nLovEKlN PILOT coNTRoLLED VALVE4 4 Sheets-Sheet 1 Filed Oct. 9, 1925 Feb. 18, 1930. 1 D. LovEKlN I PILOT CONTROLLED VALVE Filed'oot. 9, 1925 4 Sheets-Sheet 2 w MS Feb. 18, 1930. L. D. LovEKlN lPILOT CONTROLLED VALVE 4 Sheets-Sheet Filed Oct. 9, 1925 Feb. 18, 1930. 1 D, LOVEKlN l 1,747,589

PILOT GONTROLLED VALVE Filed Oct. 9, 1925 4 sheets-sheet 4 llillztented Feb. 18, 1930 UNITED STATES PATENT oFFIcE LUTHER D. LOVEKIN, 0F ABDMORE, PENNSYLVANIA PILo'r-coNTRoLLEn VALVE v l Application led October 9,

A further purpose is to 'heatl a thermostat p from the pilot light and to control the gas supply for the main burner as well as for the pilot light from the thermostat.

A further purpose is to protect a pilotlight-controlled thermostat from excessive heat from the main burner by air insulation, preferably providing cooling circulation of vthe air.

4amount of gas to the pilot during this pasn sage.

Further purposes will appear in the speci-*5) ication and in the claims.

I prefer to illustrate my invention by one general form only, modified to suit different positions of use; selecting a form which is practical, 'efiicient and inexpensive and which at the same time ',well illustrate the principles of my invention.

v Figure 1 is an eleva ion, partly lbroken away, showing an-aut atic storage type wlater heater to which my invention is ap' p 1e a l Figures 2 and 3 are opposite end elevations of the structure seen in Figures 4 and 5.

Figures 4 and 5 are central longitudinal sections of a horizontal form of the structure embodying my invention showingthe parts in different positions.

Figure 6 is an elevation, partly broken away, showing a vertical form of my invention applied to a burner. g

Figure 7 is an elevation partl broken away showing a. verticalV form of t e invention.

Figure 8 is a vertical central section show.- ing a. form of vertical pilot-valvecontrol 1925. Serial No. 61,584.

slightly diferent in gas distribution to the burner from the form in Figures 6 and 7.

Figures 9, 10, 11, 12 are sectional plan vlews of the structure seen in Figure 8, taken in the positions of section lines 99, 10-10, 11-11, 1er-12.

Figures 1 and 7 are to smaller scale than the other figures.

'In the drawings like numerals indicate like arts.

`When the gas pressure is so far reduced upon the pilot light of an automatic gasheated domestic water heater of the storage type that the pilot light goes out-as for example by street'repairs upon the gas mains or where for any other'reason the pilot goes out, the water becomes cold and the thermostat opens the main gas valve causing full ow of unconsumed gas which may asphyxi ate the members of the household or cause an explosion and which, even if harmless in these ways by reason of -passage up the chimney, wastes the gas. Inthecaseof aninstantaneous gas Water heater the gas likewise flows freely gas to the main burner and also desirably rom the pilotlight when the light goes out for any reason.

I have selected the storage type of heater for my illustration for the reason that the flow of gas in such a heater is more continuous than in the instantaneous type, causing a' greater ultimate loss of gas notwithstanding that the rate of loss is not nearly so high and the danger not nearly soI eat in it while the gas isilowing as in the lnstantaneous type.

Describing rst a horizontal form shown in Figures 1-5 The invention is shown as applied to bo1ler 10. traversed by heating flue 11 for the hot gases from burners 121 The gas is supplied pipe 13 passing throu h my pilot-controlled valve 14, thence to 15 controlled by thermostat 16. Valves 17 and 18 are inserted in the gas pipe. The pilot gas supply at 51 is connected Lto the mam gas pipe 'between the valves 14 and 15.

t ermostatic valve in an opening 26 in the end 27 of thermostatic element 28, and at the opposite end terminates in a flange or button 29 held in position in any suitable manner, as by a nut Kthreaded into the valve section.

30.v Between these ends the stem passes through a stuffing box 3l in a closure The interior of the closure is provided with a scat for the spring 33, Whose other end rests upon the valve.

The gland is screwed to position withink the end of the casing and the packing is tightened Within the gland by cover 34, the

construction being such that the valve is spring pressed to its seat and that the forward end of the spindle, in the direction of pressure of the spring upon the spindle, is loosely connected with the end 27 of the thermostatic element. vThis leaves the spindle free to be pulled backWardly, against the tension of the spring, Withoutv moving the thermostatic element. It may be held there 'by engagement with the button of an arm 35 pivoted at 36 and gravity-retracted.

The thermostat end 27 slides in a guide and closure 37 fitting Within a recess 38 in the rear end of a cup-shaped thermostat casing 39 and held Within that recess by the threaded end 40 of the valve section which fits Within the thread 41 in the casing. In the form of my invention shown in Figures 8-11, Where'the gas is passed through the casing to the pilot light, there is no utility in forming a joint at this point, but in the form of Figures 1-7 it is desirable to additionally seal at thispoint, though this seal is not relied upon Wholly to prevent gas .leakage. In both-the closure serves a guiding function. Y

The casing 39 is flanged at 42 for attachment to the Wall 43 of the heater, from which it is heat-insulated at 44. e

` `v Thethermostatic element 28terminates at its-forward end in a projection 45 fitting "Within a socket" 46 connected with and supported Vbythe easing and seals against packing 47. the bottom' of this socket. The l' packing rests upon'ange 48.

'l Thethermostat isshown as ofthe bellows throu h its terminals by conduction, from the pi ot light parts andl from the surrounding casing. v

The pilot light support is carried by the casing 39 and is in close heat-conducting contact with it. They are shown as integral. The heat-conducting connection is further increased by metallic Webs 49.

Upon the forward end of member 39 I mount the pilot light, `feeding gas to it through a tubular member 50 Which is threaded at one end for connection of the pilot gas feed pipe 5l and at the other end is fitted to receive and hold the pilot light burner 52, usually of lava or similar material. The outlets 53 of this pilot light, shown as two in number diverge to light the main burner to the best advantage, driving the gas out through an opening 54 between the member' 50 and a projection k55 which are bifurcated by the 'openings 54 and inevitably heating both of them. The heat is conducted from these terminal members 50 and 55 to the casing surrounding and in Contact with My invention contemplatesheating the Y thermostatic element from the pilot light, in order to expand the thermostatic element to hold the valve open; but the delicacy of thermostat-ie control Which makes it prossible for the pilot light to serve this purpose renders it highly desirable to protect the bellows and its surrounding structure somewhat .from the much more intense heat of the main 'enclose more than the upper part of the structure because this Will' itself shield the lower part from the heat of the burner chamber as Well as from the actual heat of the burner and I have therefore shown the cover 56 as a mere shroud about the upper inner portion Aabove the pilot light. However, 1n Whatever form this be constructed, I find that better Y results are obtained by spacing it from the metal ofthe casing 39 to provide a passage 57 open-at both ends, so that the difference in temperature due to differin g distance from the main burner and protection ofone end by the shell of the heater result in flow of air through the passage aud'eorresponding coolingboth ofthe shroud and of the metal fitting beneath it. Part or yall of the air from the passage 57 mayinclude part or all of the air feeding the pilot light. a' f f In operation if the pilot goes out the thermostatic element Will cool much faster than the Water if it be a storage type of heater, so

i be out off from the pilot light and from the main burner and in the absence of one feature of my invention it would be necessary for the operator to hold the valve stem lopen A' until the thermostatic element has heated sufficiently to perform this function. If it were permanently propped open contraction of the thermostatic element would cease to be effective to permit spring closure of the valve.

When the valve is opened, therefore, the operator places the pivoted arm beneath the button where it is held by the closing pressure of the spring, the parts occupying the position in Figure 4. The closing pressure of the spring continues to hold the arm up to its duty until continued expansion of theI thermostatic element causes the bottom of the socket 26 in the outer end of the thermostatic element to engage the end of the stem and continued expansion of the thermostatic element pushes the stem and thus the button beyond the position shown in Figure 4. TheA arm then drops away from the button leaving the stem free to follow the expansion and contractions of the thermostatic element and to close the valve with sucient contraction of this element. i

In the form shown in Figure 7 the general relation of the parts is identical with that shown in the preceding figures, with the difference, however, that because the thermostatic control valve is intended to be placed in vertical position some differences appear in additional weighting of the holding arm, construction of the shroud for directing flow of cooling air and the position and connection of the pilot light. The general assemblage is the same, the connections being such that the pilot-light-controlled valve cuts E iow of gas to the pilot light and to the main burner through the thermostatic control valve whereas the thermostatic control valve cuts off gas iow from the main burner but does not affect the pilot light.

Considering the structure from the bottom,

`the spindle, the gland construction, gas valve,

thermostatic element and connections with the thermostatic element are intended to be identical with those vshown in Figures 1 -5.

The arm is not as far off center in the vertical form as in the horizontal form and,

as an additional precaution, has therefore been provided with additional weight in the form of a yoke. This yoke comprises bars 58 rigid with arm 35', straddling the lower end of the valve and weighted adjustably at 59 to give a desired additional off-center releasing weight to insure that the arm 35 fall away rom the position in Figure 7 when the thermostatic element has operated to push the spindle downwardly beyond the position shown in Figures 7 and 8.

The structure is mounted upon-a different part of the wall 43`of the heater and in the mounting additional precaution against heat transfer from this wall is shown in Figure 8 in the complete insulation at of the bolts by which the flange 42 is held to the wall.

The protective shield 51 is here less of a shroud and more of a complete covering be# cause of the greater exposure of the parts to the heat within the wall of the burner chamber.` It is apertured at 61 for air inlet and at 62 for air outlet, opening being provided also for the pilot light and for screw 63 and gas connection 64.

The screw 63 is inserted for the purpose eff holding the bellows member in position.' The gas connection 64 affords separategas feed for the burner close to the burner. A slightly different form of the burner 52 is shown from that of the other gures and the burner is differently mounted being screwed into an opening coaxial with the sylphon element and protected by a cover 65 removable to give access to the burner.

In order to avoid the need of outside gas pipe connection for the pilot light and also to accommodate the adjustment of the flow of gas to this light I pass the gas from the compartment 6.6 in front of the valve, as considered in the direction of gas How, through the compartment containing the thermostatic element to the pilot burner. Obviously this may be done in various ways of which one convenient form is shown in Figure 8. I form an opening at 67 in the guide plate 37 and curve the forward side of this plate at 68 so as to prevent closure of this opening vby the rear end, near the lower end of the bellows. The curve at the forward end of this bellows compartment prevents the forward end of the bellows from shuttingof passage of the gas and communicates with a groove 7() which 'mergesinto a drilled hole 71 and transverse opening 72 by which the gas is ledto the passage 73 and into communication with the burner.

The screw 74 operatesasa valve to close the opening of passage 72 partially to limit the flow or wholly to seal against flow, and at the same time gives an opening through which the transverse passage 7 2 may be con trolled and the valve seat 75 may be faced.

My invention -thus provides a setting device for initiall holding the valve open, 'automatic release o this setting device, pilot light heating for thermostatic control of the entire gas supply, protection against excessive heating of the thermostat and interior flow with lentire control over the pilot light gas supply. It will be obvious that others skilled in 'near opposite ends to the art will see from my disclosure some of the other ways in which all or a part of the -benelit of my invention may be secured without'copying this form and itis. my purpose 5 therefore to cover herein all of these different forms Vwhich come within the reasonable spirit and scope of my invention.v j

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is v l. In a pilot-light-operated valve, a pilot light, a thermostatic elementf, metallic connections between adapted to cause expansion of the thermostatic element withwheat from the pilot light,` asocket connected with the thermotsatic element, a stem movable in said socket and adapted to be pushed by the bottom of the socket, avalve on the stem, a Valve seat with which the valve isadapted' to cooperate, spring retraction for l thev valve adapted normally to hold the valve against its seat and when the valve is'open to hold the stem against the bottom of lthe socket, a pivoted arm adapted normally tofswing away from the stem or into engagement with it and means on the stem engaged by the arm and adapted to hold the valve partly'open until the stem is engaged by thebottom of the socket. f f

2. In a pilot-light-controlledvalve, a pilot light, a thermostat in mechanicalconnection therewith, a spring-pressed yalve and stem opened by movement of the thermostat and a cover about the connection between the pilot light and thermostat providing air passage for cooling air circulation between.

3. A pilot-light-controlled valve comprising a pilot light, a thermostatic element heated therefrom and a vvalve controlled 4o thereby, in combination with air-flow cooling mechanism exterior thereto protecting the ortion thereof within the burner chamber rom excessive heat. v

4. In a pilot-light-valve-control, walls forming a heater chamber, and automatic pilotlight-controlled valve therefor and of which the pilot light and adjoining parts project within the casing, a thermostatic element heated by the pilot light and a cover for the portion projecting within the casing having air spacing between it and the pilot-lightcontrolled-valve to protect the pilot light and associated parts from excessive heatmg within the chamber, the air spaces being open provide coolingY air circulation.

5. In a pilot-light-control valve, walls *forming a heater chamber, an automatic pilot light valvev control of which the pilot light and adjoining parts project within the chamber, a thermostatic element heated by the pilot light and a cover for the portion projecting within the chamber having vair spac-l ing between it and the pilot light and adj oinmgl-.parts to form a cooling passage to protect hem from excessive heating within the chamel'. e,

6. In a pilot-light-controlled valve for controlling fuel suppl to a main burner and to the pilot light, a pilot light, a metallic casing adjoining the pilot li ht, a thermostat element, a seat for the t ermostat adapted to receive heat kfrom the casing and to transmit heat to the thermostat whereby the thermostat' will be heated by the pilot light, a valve stem axially in line with the thermostat and having a slip connection with the thermostat, a valve on the stem, a-valve seat intermediate the length of the stem cooperating with the valve to control the suppl of fuel to the main burner and to the pilot light, a spring surroundingthe stem and tending to seat the valve to shut off the fuel to the main lburner and to the pilot light and automatically disengaging means coacting with said stem to hold the valve in partly open position.

LUTHER D. LOVEKIN.

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