US 2871930 A
Description (OCR text may contain errors)
Feb. 3, 1959 D. F. DRow FUEL CONTROL MECHANISM FOR HEAT APPLIANCES Zfiheets-Sheet 1 Filed Jan. 30, 1952 :EIIfEil I v M w 3 mm m N w u n w A III. HA
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FUEL conrnor. MECHANISM FOR HEAT 7 APPLIANCES Donald F. Drow, Los Angeles, 'Calif., assignor to Minneapolis-Honeywell Regulator Company, a corporation of Delaware Application January 30, 1952, Serial No. 269,083
7 Claims. (Cl. 158'- 131) The invention relates to safety controls for heat appliances utilizing an intermittently operated main burner ignited by a constantly operating pilot burner, and more od of obtaining this 100% operation involves the use of a double type valve construction separately controlling the fuel flow to the main and pilot burners. This is frequently done mechanically by the use of a pair of coplanar, concentrically arranged valve seats for controlling flow through separate passages to the main and pilot burners, and which are simultaneously engaged and closed off by a valve movable to such seats under the control of thermostat means responding to an extinguishing of the pilot burner. 100% or complete shut off operation is important in connection with certain fuels such as liquid petroleum gases and other heavier than air fuels which may provide a dangerous accumulation of fuel from the small pilot flow.
One class of safety controls of the above character is what may be termed the manual resettable type in which the thermostat means releases the valve for automatic closing (under spring action) upon extinguishing of the pilot burner, and the valve is subsequently displaced toopen position and into operative attachment of the thermostat means by what is referred to as a reset means-- most commonly a manually displaceable member. Another refinement made in controls of the manually resettable type has been the provision of means for preventing the fiow of fuel to the main burner during the resetting operation and igniting of the pilot burner. Controls incorporating this feature are frequently referred to as safe lighting in that there is removed by the provision of such feature the hazard, otherwise present, of the burning of the hand of the person relighting the pilot burner. The safe-lighting provision has been accomplished mechanically in various ways principally by a structural locking against movement of the reset means in the normal open position of a secondary valve inscrted in the passage to the main burner, or by the provision of means for automatically displacing to closed position such a secondary or auxiliary valve during the resetting operation.
It is an object of the present invention to provide a fuel control mechanism of the character described employing an improved system and arrangement and co action of parts which will provide the 100% and safelighting features above discussed, while avoiding the use 2,871,930 Patented Feb. 3, 1959 "ice and structures by which these features have been heretofore accomplished and the attendant disadvantages thereof. It is therefore an object of the present invention to provide a safety control mechanism of the character described Which is simple and straightforward in its design and operation and is yet composed of a minimum number of sturdily formed parts designed and arranged for, and co-acting to produce, completely fool-proof operation over a very long period of use.
Another object of the present invention is to provide in a safety control mechanism of the character described an improved form of reset mechanism functioning in a simple, straightforward and fool-proof manner and positively preventing the flow of fuel to the main burner during the resetting operation and until the pilot burner has been ignited and its operation properly established.
A further object of the present invention is to provide a safety control mechanism of the character described which is designed for compactness and ease of construction and assembly which enhances its range of utility and reduces its cost.
The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following description of the preferred form of the invention which is illustrated in the drawings accompanying and forming part of the specification. It is to be understood, however, that variations in the showing made by the said drawings and description may be adopted within the scope of the invention as set forth in the claims.
Referring to said drawings:
Figure l is a plan view of a fuel control mechanism constructed in accordance with the present invention.
Figure 2 is a cross-sectional view taken substantially on the plane of line 22 of Figure 1.
Figure 3 is a fragmentary cross-sectional view taken substantially on the plane of line 33 of Figure 2.
Figure 4 is a fragmentary cross-sectional view similar to Figure 3 but showing the control valve turned to light position.
Figure 5 is a fragmentary cross-sectional view similar to Figure 3 but showing the control valve turned to 01f position.
Figure 6 is a fragmentary cross-sectional view similar to Figure 2 showing the reset mechanism in an inserted (manually displaced) position.
Figure 7 is a fragmentary cross-sectional view similar to Figure 6 but showing the reset mechanism in a normal (manually released) position.
Figure 8 is a perspective view of a part of the reset mechanism.
Figure 9 is a diagrammatic representation showing the main burner, pilot burners, the thermostatic means and the fuel control mechanism in their operative relationship.
The safety control mechanism of the present invention and as illustrated in the accompanying drawing consists to a main burner 3 of a heat appliance; a manually enof the more relatively complicated types of mechanisms gageable and displaceable reset means 13 for the valve and its thermostat means 27; a passage 14 by-passing the valve 11 from the upstream side for taking off pilot gas during the resetting operation; a valve 16 controlling the flow through the by-pass passage 14 and connected to the reset means 13 for operation thereby during the resetting operation; and a manually controlled valve 17 of the multiple passage and position type having inlets 18 and 19 connected to the passages 12 and 14 respectively and having outlets 20 and 21 for connection to 3 the main and pilot burners respectively; the several parts having their operations so correlated and their interconnecting passages so arranged as to insure and make fool-proof the 100% and safe-lighting operations hereinabove discussed.
Preferably the several parts are unitarily assembled in a casing or housing 22 providing the main passageway 12 therethrough leading from an inlet opening 23 adapted for connection as by conduit 24 to source of fuel such as gas, and being enlarged interiorly to provide a chamber 26 for accommodating the valve 11 and its thermostat control means 27 and portions of the reset means 13.
The thermostat means 27 may be of any of the types commonly used in pilot safety valves such as a bi-metal latch as disclosed in Jenkins Patent No. 2,322,520, issued June 23, 1943, or of the deflecting tube type disclosed in Drow Patent No. 2,530,942, issued November 21, 1950, or of the thermo-electric type as herein illustrated. This latter type is composed of a thermo-couple 4 which is mounted for heating by the pilot flame 1 for generating an electric potential which is applied to a field winding 28 provided on a magnetic core 29 which functions so long as energized to hold in attracted position an armature 31. Upon extinguishing of the pilot flame and ensuing collapse of the magnetic field, the armature 31 is released from the pole faces 32 of the horseshoe core here depicted for displacement therefrom under spring action to effect a closing of valve 11. For convenience, binding posts 33 and 34 are provided on an end cover 36 of a case 37 provided for the magnetic core 29 and its winding 28 and armature 31, for connection to the leads of the thermo-couple. The thermostat means 27 here employed thus has, in common with the other types of thermostat means noted, a part 31 which is movable between caught and released positions and its maintenance in caught position is dependent upon the existence of flame at the pilot burner.
In accordance with the present construction, the valve 11 and thermostat part 31 are mounted for aligned and coaxial movement so that movement of the part 31 from caught to released position, from left to right as viewed in Figure 2, will be accompanied by a similar left to right movement of the valve 11 from open to closed position.
A seat 38 for valve 11 is provided by an interior wall 39 of the housing defining the inner end of a valve chamber 26 adjoining passage 12. As here shown, the outer normally open end of chamber 26 is closed by the insertion therein of the case 37 of the thermostatic means, the latter being secured and sealed by a ring nut 42 against an internal shoulder 41 provided by the housing, thus placing the thermostatic means in direct alignment with valve 11. The latter is here mounted for reciprocation to and from the seat 38 by means of a valve stem 43 secured to and projecting axially from the opposite sides of the valve, and having one end portion 44 slidably mounted within a bore 46 provided in a protuberance 47 forming part of wall 39 at the interior side of valve seat 38.
The opposite (left) end portion 48 of valve stem 43 is here slidably mounted within a tubular extension 49 fixed to and projecting axially from the armature 31, the tubular extension 49 being in turn supported co-axially for reciprocation in a bearing 51 provided at the inner end of case 37. Secured to the inner free end of the tubular extension 49 for movement therewith is a generally disc shaped part 52 thus supported in axial juxtaposition to valve 11 for displacement of the latter to closed position upon movement of the armature 31 to its released position.
In accordance with the present construction spring means is provided for constantly urging valve 11 and the thermostatically actuating part 52 towards each other and to the closed position of the valve and the released position of the part 31. In the construction illustrated matically opened upon depressing the this spring means includes two helical springs 53 and 54. Spring 53 is mounted about the valve stem portion 44 in compression between the valve 11 and the protuberance 47 so as to constantly urge the valve 11 towards thermostatic part 52 and to an open position. Spring 54 is mounted about the tubular extension 49 and in compression between the end wall 56 of the case 37 and part 52, so as to constantly urge this part and the integrally connected armature 31 to the right, as viewed in Figure 2, thus constantly urging the displacement of armature 31 from its caught to its released position and part 52 toward valve 11 and its closed position. Spring 54 is somewhat stronger in its action than spring 53 so that when the armature 31 is released from the pole faces 32, spring 54 will overpower spring 53 to effect a closing of valve 11.
Cooperating with the valve 11 and thermostatically controlled shut-off mechanism described above is the reset means 13 which here includes a wedge shaped member 57 for effecting, upon displacement in one direction, a separation of the valve and part 52 thus co-acting with the spring means above noted to hold closed valve 11 while displacing part 52 to caught position. Assuming the pilot burner ignited and the magnet energized and the thermostatic part thereby held in caught position, spring 54 will be immobilized and a return movement of the wedge member 57 will permit an opening of valve 11 under the influence of spring 53. Wedge member 57 is here mounted for reciprocal motion perpendicular to the axis of the valve 11 and part 52 by securing its outer (widest) end 58 to the inner end 59 of a shaft 61 carried by the housing for reciprocation perpendicular to the aforementioned axis. Preferably the shaft 61 is mounted through a bore 62 in a plug 63 closing an opening in the housing provided for convenience in mounting of the parts. The outer end portion of shaft 61 projects from the plug 63 for manual engagement and is normally maintained in a retracted (outwardly extended) position by a helical spring 64 mounted about the shaft 61 in compression between a head portion 66 provided on the outer end of the shaft for manual engagement and a washer 67 at the outer side of plug 63, the washer 67 here holding in compression a packing gland 68 mounted in a groove provided in the plug surrounding the shaft.
As hereinabove noted by pass passage 14 is provided for leading gas from the upstream side of valve 11 to the pilot burner during the resetting operation which requires passage 14 to be closed during normal running operation, and the valve 16 above noted, is provided in the passage 14 and connected to the reset means 13 so that the valve is open only during the resetting operation. For convenience and as a feature of the present construction, valve 16 is provided directly on the inner end of shaft 61 for movement to and from a valve seat 69 provided at the inner end of plug 63. In this manner valve 16 is normally held closed by spring 64 urging shaft 61 to an outwardly extended position, but is autoshaft during the resetting operation. Passage 14 is formed in the housing 22 and connects to a side of plug 63 where the passage is continued through the plug to an enlarged portion of bore 62 forming a continuation of the passage to the valve seat 69 and chamber 26.
In order to permit the wedge to properly follow the relatively transverse movement of the thermostat part 52 and valve 11 perpendicular to the line of displacement of the wedge member during the re-setting operation, the wedge member is preferably pivotally secured to the inner end 59 of shaft 61. As here shown this pivotal attachment is effected by extending a reduced pin like end portion of the shaft through a relatively larger opening in the end 58 of the wedge member, and for convenience expanding the outer end of the pin extension to prevent detachment. For simplicity and ease of construction the wedge member 57 may be formed of sheet E J metal as illustrated in Figure 6 whereinit will be seen that opposite sides 71 and 72 are folded in parallel spaced relation, perpendicular to the end 58 above noted, so as to thereby define a slot 73 between the sides to accommodate the valve stem portion 48 upon insertion of the sides 71 and 72 between the valve 11 and thermostat part 52. Sides 71 and 72 are formed with a flat face 74 adapted for sliding engagement with a flat face 76 provided on the back side of valve 11. Adjacent their inserted ends 77 (opposite end 58), the sides 71 and 72 are formed with a level or parallel opposite side portion 78 which is adapted to normally engage a flat end face 79 on member 52. Contiguous to portion 78 and extending therefrom to the end 58, are relatively inclined por tions 81 which upon advancement of the wedge member during the re-setting operation are arranged to engage a similar tapered or conical face 82 on the part 52 contiguous to face 79. In the present construction of the wedge member and associated valve 11 and part 52 there is a relatively small area of contact whereby friction between the members is reduced to a point where smooth displacement of the parts is eifected during the re-setting operation without liability to sticking or jamming. It will also be noted that the level or parallel portions 78 are in position between the part 52 and valve 11 in the normal outwardly extended position of the reset means. There is accordingly at least a preliminary insertion of the wedge between the valve and part at all times.
The manual control valve 17 above noted completing the safety features of the control is preferably of the rotary plug or cock type having a conical shaped plug valve member 83 mating with and journaled for rotation upon a complementary tapered wall 84 formed in the housing 22 and extending divergently to an outer side 86 to provide an open bore for receipt. of the conical plug 83. The plug member 83 is here secured in the bore by a retainer spring 89 held in compression between an annular shoulder 88 provided on the member 83 and a cap 87 secured to the outer side 86 of the housing.
As will be seen from Figure 2 the bore for the plug member intersects and provides a continuation of the main fuel passage 12 at the down-stream side of valve 11.
It will also be noted that plug member 83 is formed with an axially extended bore 91 registering with passage 12 and thus forming the main inlet 18 to the control valve. The main fuel outlet 20 is provided in the housing 22 and'extends to the wall 84 at the side of plug 83 for registration with a transverse passage 92 in the plug 83 extending from the central bore 91. As will be seen from Figure 3, outlet 20 is defined as the valve terminal end of a passage 90 formed in the housing leading to a fitting 95 for main burner conduit 100. Rotation of the plug to the position "llustrated in Figures 1 and 3 places port 92 in registration with passage 20 thus constituting what is here denoted as the on position of the valve wherein, so far as valve 17 is concerned, flow to the main burner is established. As a convenient means for controlling the amount of maximum flow of fuel in the on position of the valve, a valve plug 93 may be threaded into the bore 91 as here illustrated to permit the extension of the plug down to and partially across the port 92 so as to thereby selectively restrict, and thereby control, the fuel flow therethrough. A screw driver slot 94 or other convenient tool engaging form as desired may be provided on the outer side of plug valve 93 so as to permit its ready adjustment in the field to accommodate for varying fuel pressures that may be encountered. Preferably a closure member 96 is provided at the outer end passage 92 vided in the plug valve 83 an additional passage or port 99 leading from the interior bore 91 to the outside of the plug in diametrically opposed relation to the port or and in position to register with the pilot gas inlet 19 being the terminal end of bypass passage 14 at the interior wall 84 of the control valve housing. Port 99 is also provided with a circumferentially extending channel or groove 101 in the outer periphery of plug member 83, and which here extends for about 90 around such periphery so as to simultaneously connect inlet port 19 to outlet port 21 leading to the pilot burner in the light position (see Figure 4), port 21 being located at the same transverse plane as port 19. As will also be seen from Figure 4, port 21 is the terminal end of passage 102 provided in the housing and leading to a fitting 103 for a conduit 104 leading to the pilot burner. In the light position provision is made by the control valve to shut ofi the flow of fuel to the main burner outlet 20 while providing for the by-pass flow of pilot fuel as discussed. This is here effected by locating a solid peripheral portion 106 across port 20 in the light position of the valve as illustrated in Figure 4.
The control valve is provided with a third position herein denoted as the o position which is one rotated clockwise from the light position and is illustrated in Figure 5. In this position it will be seen that the solid portion 106 is of such an extent as to continue to block oifport 20 while a diametrically opposed solid portion 107 moves across the pilot outlet port 21 thus shutting ofi fuel flow to both the main and pilot burners.
The several combinations provided by the control valve are important and may be summarized as follows. In the on position inlet 18, in constant communication with bore 91, is connected to both the main and pilot burner outlets 20 and 21 while the by-pass inlet port 19 is closed ofi by the solid portion 106 aforementioned. In the light position both inlet ports 18 and 19 are connected to the pilot outlet port 21 while the main fuel port 20 is closed. In the off position both outlet ports 20 and 21 are closed. The importance and automatic interaction of these several combinations of the control valve with the re-set mechanism and auxiliary by-pass valve 16 will be more clearly understood in a complete analysis of operation, a brief description of which follows.
Starting with the normal open or run position of the mechanism as illustrated in Figures 3 and 7, and assuming the pilot burner properly operating, the thermo-couple heated and the magnet thereby energized, armature 31 will be retained in caught position 'thereby holding part 52 in a retracted position immobilizing spring 54, and permitting the valve 11 to be in open position under the influence of its opening spring 53. In this position of the parts fuel may flow from inlet 23 into chamber 26 past open valve 11 and through passage 12 into the central inlet 18 of the rotary plug valve 83. At the control valve and as seen in Figure 3 of the drawing, fuel may pass from passage 91 through registering ports 92 and of bore 91, the member having the additional function in 20 to the main burner. At the same time fuel may pass from passage 91 through aligned ports 99 and 21 to the pilot burner.
Should the pilot burner be extinguished for any reason, the thermocouple will cool thereby diminishing the electric potential applied to winding 28 and the consequent magnetic field thereby releasing armature 31 from its caught position for displacement by spring 54 to its .released position as illustrated in Figure 2. In this movement part 52 engages the so-called level portion of the wedge member and swings the latter forcibly against valve 11 to effect its closing against the resistance of spring 53. With main valve 11 closed, fuel flow is shut off to both main and pilot burners, since as will be seen from Figure 3 both outlet ports 20 and 21 depend on fuel from the inlet port 18 which is in turn controlled by valve 11. It should also-be noted that in this on position of the valve by-pass port 19 is closed. This is important in rendering non-operative the resetting operation when the control valve is in on position. If the reset is depressed, the Opcning of auxiliary valve 16 will have no effect since the terminal end 19 of passage 14 is closed at the control valve. Also the insertion of wedge member 57 between valve 11 and part 52 will maintain the valve in tightly seated position while displacing the armature 31 to the pole faces 32. However, since there is no pilot flame or resulting magnetic field, the armature is not held in attracted position but will follow back over the inclined sides of the wedge member as the latter is retracted by spring 54 upon manual release of the reset. During such retraction spring 54 operating through part 52 and wedge member 57 constantly holds the valve 11 in closed position.
It is accordingly necessary in the operation of the present device to turn the manual control valve 17 to its light position in order to re-establish operations of the appliance. In this position of the control "alve, as illustrated in Figure 4, fuel flow through the control valve is, as above noted, permitted from both inlets 18 and 19 to pilot outlet 21 while main burner outlet 24 is shut off. As the reset shaft 61 is depressed, as illustrated in Figure 6, valve 16 opens thereby establishing pilot flow from the upstream side of valve 11 to the pilot burner which may be ignited. l t is important to note that the control valve effectively blocks any flow to the main burner port 20 from the by-pass inlet port 19. In the depressing of the reset shaft 61, wedge member 57 serves to hold valve ll. closed while displacing armature 31 to the pole faces 32 as shown in Figure 6. The operator needs to hold the reset depressed for a sufiicient period after lighting of the pilot burner to provide an energizing of the magnetic field and resulting in holding of the armature. If the reset is not held for this requisite period no harm will be done since the armature will merely return to its released position during the course of which valve 11 is constantly held in closed position by spring 54 as illustrated in Figure 2. However, by holding the reset in depressed position for the requisite time to establish the magnetic field, armature 31 will be held in attracted or caught position, as shown in Figure 7, thereby immobilizing spring 54. Ensuing releasing of the reset will permit valve 11 to open under the action of its spring 53 while pivotally displacing wedge member 57 around its connection with the reset shaft 61. With the main valve thus opened, there is still no flow to the main burner until the control valve is moved to on position. Also, it will be noted that immediately upon opening of main valve 11, pilot port 21 receives fuel from the main inlet 18 of the control valve by way of circumferential groove 101. Since this groove remains in constant registration with port 21 upon rotation of the control valve from light to on position, see Figures 3 and 4, there is no interruption of the pilot burner occasioned by this change of the control valve. It will thus be apparent that no inadvertent operation of either the reset mechanism or control valve can in any way interfere with or prevent the 100% or safe lighting characteristics of the present mechanism, but on the contrary such complete safety features are at all times assured and automatically provided for.
When desired and for convenience in shutting down the heat appliance, the manual control valve may be turned to its off position as illustrated in Figure thereby shutting oif the flow to both the main and pilot burners. The extinguishing of the pilot burner causes an ensuing r lease and shutting olf of main control valve 11 so that fuel flow is doubly checked at all points. If, instead of wishing to completely close down the operation of the appliance, it is desired to leave the appliance in a standby conditicn, the control valve may be moved to light position, thereby effectively shutting off the flow of fuel to the main burner while leaving the pilot burner in operation. The appliance may be thereafter put in operation by merely changing the control valve from its light to its on position.
1. A pilot operated valve comprising, a valve member movable between open and closed positions, thermostat means responsive to a pilot burner flame and including a part movable between caught and released positions, spring means engaging said part and said valve member and urging said valve member into open and closed positions in accordance with the caught and released positions respectively of said part, and reset means including a wedge shaped member mounted for joint movement with said part and said valve member and being formed with opposite tapered sides slidably mounted upon and positioned between said part and valve member for relative movement therebetween to selectively urge said part to caught position while holding said valve member in closed position.
2. In a pilot controlled safety valve for heat appliances, a housing, a valve mounted in said housing and movable to open and closed positions, thermostatic means responsive to a pilot burner flame and including a part mounted in said housing for movement coaxially of said valve between caught and released positions, said valve and part being formed with axially opposed faces, spring means urging said valve and part toward each other and to closed and released positions respectively, a wedge shaped member positioned between said valve and part, formed with relatively tapered sides slidably engaging said faces and said member being mounted for joint movement with said valve and part and for reciprocal movement relative thereto perpendicular to the axis of movement of said valve and part, and an actuating member carried by said housing for reciprocation in alignment with said wedge member and being pivotally secured thereto and extending from said housing for manual engagement and displacement, said wedge member being arranged on displacement in one direction by said actuating member to eifect a relative separation of said valve and part urging the latter to caught position while holding said valve in closed position against the resistance of said spring means, said wedge member being arranged on displacement in a return direction and with said part in caught position to swing about its pivotal connection to said actuating member and release said valve for movement toward said part and to open position under the urge of said spring means.
3. In a fuel control mechanism of the character described, a thermostatically controlled shut-off valve of the manually rcsettable type responsive to the flame of a pilot burner and mounted in a passage providing for and controlling the flow of fuel to a main burner of a heat appliance, manually engageable and displaceable rcset means for said valve, a passage by-passing said valve from the upstream side thereof, a second valve mounted in said by-pass passage and connected to said reset means .for displacement thereby from a normally closed position to an open position during the resetting operation, a third valve of the multiple passage and position type having first and second inlets connected to said first and second named passages respectively and first and second outlets adapted for connection to the main and pilot burners respectively, said third named valve having a first position connecting said first inlet with said first and second outlets while closing off said second inlet, and said third valve having a second position connecting said first and second inlets with said second outlet while closing said first outlet.
4. A fuel control mechanism as defined in claim 3 wherein said third valve is provided with a third position closing off both said first and second outlets.
5. A safety valve for a fuel system comprising, a housing having first and second passages therethrough adapted for communication to a fuel source and to heating means including main and pilot burners, a spring actuated main valve disposed Within said first passage and having a normally open position allowing fuel flow through said first passage and a closed position closing said passage, thermostatic means responsive to said pilot burner and including a part having caught and released positions, said part being spring actuated and connected to said main valve to move the latter into closed position when said part is in released position but permitting the opening of said main valve when in caught position, reset means of wedge shape engaging said main valve and being displaceable in one direction to hold said main valve in closed position and said part in caught position and displaceable in a return direction to release said main valve to move to normal open position, a manually operated control valve having first and second inlets connected to said first and second passages respectively on the discharge side of said main valve and having first and second outlets adapted for connection to the main and pilot burners respectively and having off, on, and light positions, said control valve in said 011 position closing both said outlets, said control valve in said on position connecting said first inlet to both said outlets while closing said second inlet, said control valve in said light position connecting said first and second inlets to said second outlet while closing said first outlet, and a valve disposed in said second passage and connected to said reset means and displaced thereby to open position when said reset means is displaced in said first named direction and to closed position when said reset means is displaced in said return direction.
6. In a fuel control mechanism of the character de scribed, a housing formed with a main fuel passage for supplying fuel to main and pilot burners of a heat appliance, a thermostatically controlled shut-off valve of the manually resettable type mounted in said passage and being responsive to the flame of the pilot burner, manually engageable and displaceablereset means for said valve, an auxiliary passage connected to said main passage at the upstream side of said valve, a second valve mounted in said auxiliary passage and connected to said reset means for displacement thereby from a normally closed position to an open position during the resetting operation, and a manually engageable rotary plug valve journaled for rotation in said housing in a communication with said main and auxiliary passages, said housing being formed with main and auxiliary outlets communicating with said plug valve, said plug valve having on, light and oif positions and being formed to provide in said on position for the communication of said main passage with said main and auxiliary outlets while closing off said auxiliary passage and being formed to provide in said light position for the communication of said main and auxiliary passages with said auxiliary outlet while closing ott said main outlet and being formed to provide in said off position for the closing 01f of both said main and auxiliary outlets.
7. A pilot operated safety valve comprising, a housing, a valve member mounted therein and movable between open and closed positions and including a co-axially extending valve stem, thermostatic means responsive .to a pilot burner flame and including a part slidably mounted on said valve stem for movement between caught and released positions, spring means engaging said part and said valve member and urging said valve member into open position when said part is in the caught position and urging said valve member into closed position when said part is in the released position, a generally U-shaped reset member having a pair of spaced parallel legs mounted on opposite sides of said stem between said valve member and part, and a manually engageable reset stern carried by said housing and having an articulated connection to said reset member for permitting reciprocal displacement of said legs transversely of said stem and movement of said legs jointly with said valve member and part axially of said stern, said legs being formed with opposite tapered sides slidably engaging said valve member and part whereby upon transverse displacement of said reset member by said reset stem said part will be displaced to caught position while said valve member is simultaneously displaced to closed position.
References Cited in the file of this patent UNITED STATES PATENTS Re. 22,068 Joseting Apr. 4, 1942 2,309,709 Paille Feb. 2, 1943 2,361,945 Jackson Nov. 7, 1944 2,362,011 Jeff-ers Nov. 7, 1944 2,372,537 Wantz Mar. 27, 1945 2,455,542 Weber Dec. 7, 1948 2,590,674 Bodey Mar. 25, 1952 2,591,897 Weber Apr. 8, 1952 2,604,107 Huntington July 22, 1952 2,616,710 Woodruff Nov. 4, 1952 FOREIGN PATENTS 218,209 Great Britain of 1924 232,331 Switzerland of 1944