US2920693A - Flow interrupter for thermoelectrically powered control devices - Google Patents

Description

Jan. 12, 1960 Filed D66. 5, 1951 I J. H. THORNBERY FLOW INTERRUPTER FOR THERMOELECTRICALLY POWERED CONTROL DEVICES 2 Sheets-Sheet 1 I I A, I 9- lo "11?: G I A l. 49

@Ifi r1 ,4 a0 i "*1 2 x 7 w T'" 1:46 .50 43 7 4 4 INVENTOR. r/bhnjf. Thor/25w Jaw. Luau, Jim! I 042440 Jan. 12, 1960 Filed D60. 5. 1951 POWERED CONTROL DEVICES 2 Sheets-Sheet 2 INVENTOR.

United States Patent FLOW INTERRUPTER FOR THERMOELECTRI- CALLY POWERED CONTROL DEVICES John H. Thornbery, Whitefish Bay, Wis., assignor to Baso Inc., a corporation of Wisconsin Application December 5, 1951, Serial No. 259,918-

8 Claims. (Cl. 158-431) This invention relates, in general, to thermoelectrically powered control devices, and has .particular relation to an improved flow interrupter for shutting off the supply of gas to a main burner during the operation of cocking a pilot burner valve to open position and a connected armature to attracted position.

Thermoelectric safety shut-off devices which depend upon a small thermoelectromotive force for maintaining a desired flow of fuel and which operate to shut off the flow of fuel upon extinguishmcnt, for example, of a pilot burner flame, require cocking means for manually cockingor resetting the device. These cocking devices usually move an armature to attracted position and a valve to open position, or a switch to closed position to establish the desired flow of fuel. If the valve or other control device is operated to set up the supply of fuel to the main burner when the cocking device is operated and irrespective of Whether the pilot burner is lighted, unburned gas passing, for example, to the main burner, enough to cause a dangerous flame, might accumulate in the combustion chamber pending the lighting of the ,pilot burner.

The flow interrupters previously proposed for shutting ofithe fiow of fuel to the main burner during the cocking or resetting operation have been of mechanical or electrical form. One form of mechanical flow interrupter as previously proposed required a complicated and unwieldy linkage system, and another form mechanically releases a flow interrupter valve for movement .to closed position by the operation of the cocking device. One electrical form of flow interrupter opens the electric circuit for an electroresponsive valve, with resulting closing of such valve during the operation of the cocking device.

One of the main objects of the present invention is to provide a new and improved flow interrupter which operates magnetically to close an electroresponsive valve for shut off of the flow of fuel to the main burner during the cocking or resetting operation.

Another object of the invention is to provide, in combination with a thermoelectrically powered magnet operator for actomatically operating a valve member for a main burner responsive to changes in temperature or other conditions, a magnetic shunt which by the operation of the cocking device is operated to position to shunt the magnetic flux away from the armature of the operator to prevent the opening of the valve member for the main burner during the cocking operation.

Another object of the invention is .to accomplish the results set forth without physically contacting the valve mechanism or associated parts.

Another object of the invention is to provide a magnetic shunt of the character set forth which acts upon depression of the cocking button to move the valve member for the pilot burner to open position and its connected armature to attracted position.

iknother object is to provide an apparatus for controlling the flow of fuel to fluid fuel burning apparatus lam a main-valve forcontrbllingthe flow of fuel to ice the main burner, an electromagnetic operator for the main valve, and a safety shut-off valve for a pilot burner, cocking means for manually cocking the pilot burner valve to open position, and means, more P r icularly magnetic shunt means, actuated by the cooking operation of the pilot burner valve to position shunting the mag,- netic flux of the magnetic operator for the main valve to assure, during the cocking operation of the pilot burner valve, closing of the main valve against any tendency the electromagnetic operator might otherwise have to hold the main valve in open position. This eliminates any possibility of manually cocking the pilot burner valve to open position without shutting off the flow of fuel to the main burner such as might occur in apparatus according to the present invention where, for example, the apparatus is in operation and the fuel for the main burner is momentarily shut oif or fails and a cocking operation for the pilot burner valve is accomplished before the thermoelectric generator has cooled suff ciently to drop out the main valve with resulting closing of the main valve.

Further objects and advantages and various modifications and adaptations of the invention will appear from the following detailed description taken in connection with the accompanying drawings.

In the drawings:

Figure l is a sectional view ofa control device embodying the present invention, taken on the line 1-1 of Figure 3, and shows diagrammatically one illustrative system employing the same;

Figure 2 is a front elevational view of the control device shown in Figure l 1 Figure 3 is an end view of the device looking toward the right-hand end of the device as it is shown in Figures 1 and 2; and c Figure 4 is a top plan view of the electromagnet of the thermoelectrically powered electromagnet operatorfor the main valve member.

Referring now to the drawings, the embodiment of the invention selected for illustration comprises a valve body 1 having a gaseous fuel inlet 2, a first gaseous fuel outlet 3, and a second gaseous fuel outlet 4.

A fuel supply pipe 5 is connected to the inlet 2, and a .fuel supply pipe 6 is connected to-the outlet 3. Another fuel supply pipe 7 is connected to the outlet 4. The wall 8 has a truncated conical bore 9 in which a truncated conical gas cock 10 is seated forturning movement. The inlet 2 opens into the bore .9, and .at diagrammatically opposite position the wall 8 has an opening 11 which opens into the interior of the valve body 1 for passage of gaseous fuel to the outlets 3 and 4.

The cock or plug 10 has a passage 12 extendingvdiametrically therethrough, and an externally exposed finger piece 13 for turning the plug to its On and Off positions. In the On posit-ionwhich maybe indicated, for example, by register of an arrow or pointer 14 on the finger piece 13 with an On marking on the valve body 1the passage 12 registers with the inlet 2 and with the opening 11 for passing gaseous fuel into the interior of the valve body 1, When the cock 0 is in Off" position, as indicated, for example, by register of arrow or pointer 14 with an 0f marking on the valve body 1, the passage 12 is completely outof register with the inlet 2 and opening 11 and shuts oil? the How of gaseous fuel into the valve body 1.

The fuel supply pipe 6 leads to a main burner 16, for

example, through a mixing chamber 17 to which airis admitted through adjustable air inlets (not shown) for admixture with the gas, as well understood in the art. The pipe 7 leads to apilot burner 18 for the supply of gaseous fuel thereto. The pilot burner 18 is located in juxtaposition to the main burner 16 to maintain a pilot flame for igniting the burner 16. The burner 16 may be the main burner for a space or water heater, or it may be any other burner.

An armature arm 20, carrying an armature 20', is pivoted on the upper end of a bracket 21 by a pair of screws'one of which is shown at 22, for example, in the manner more fully disclosed in the copending application of Donley S. Collins, Gerald E. Dietz, and Adolph I. Hilgert, Serial No. 249,778, filed October 4, 1951, which was amended to remove the names of Donley S. Collins and Gerald E. Dietz, and issued April 30, 1957, as

- Adolph J. Hilgert Patent No. 2,790,937. A main or first valve member 23, connected at 24 to the armature arm 20, is adapted to seat against an annular valve seat 25 at the inner end of the outlet port 3 to shut ofl. the flow of gaseous fuel to the main burner 16. The valve member 23 preferably has relative movement at the adjacent end of the connection 24 for self-accommodation to the valve seat 25, and has open position separated from the seat 25 for'flow of fuel to the main burner.

' A contractile spring 26 is connected at one end to the armature arm 20 and, at its other end, to the bracket 21 at 27. This spring yieldingly urges or biases the armature arm 20 to retracted position closing the valve member 23 against the valve seat 25.

The thermoelectrically powered electromagnet operator, designated in general at 28, is preferably of the type more fully disclosed and claimed in the copending application of Donley S, Collins, Gerald E. Dietz, and Adolph I. Hilgert herein previously identified.

Suifice it for purposes of the present application to state that the operator 28 has a core comprising a pair of small diameter posts 29, the ends of which are expanded in openings 30 in a pair of pole pieces 31 at one end and in a common pole piece 32 at the other end, and thereafter heattreated, which causes a deformation and joining of the grains of metal so that the posts 29 and pole pieces 31 and 32 are practically in one piece. Where the material used for the core of the operator will permit, the posts 29 and pole pieces 31 and 32 may be formed in one piece. The coil 34 is wound around the posts 29 and between the pole pieces 31 and 32 and comprises, as an illustrative example, approximately 72 turns of No. 15 gauge copper wire.

The single thermocouple 35 comprises a pair of dissimilar thermocouple elements 36 and 37 joined at 38 to form a hot junction disposed in the pilot burner flame or where it will be heated by the flame of the pilot burner 18 as long as the pilot burner is ignited. One cold junction 39 of the thermocouple 35 is connected in circuit with one end of the coil or winding 34 by a conductor 40, and the other cold junction is grounded at 41. The other end of the coil 34 is connected by a conductor 42 to ground at 43, preferably through a thermostat or other condition responsive device 44, or combination of such devices, for opening and closing the circuit of the coil 34 upon the occurrence ofpredetermined conditions.

A thermoelectric safety shut-off device is provided as indicated, in general, at 46 in Figure 1.

Suflice it for purposes of the present application to state that the device 46 comprises a generally U-shaped magnet frame 47 carried by a terminal bushing 48. A coil 49 wound around the legs of the magnet frame 47 is grounded at one end at 50. The opposite end of the coil 49 is connected in circuit with the cold junction 39 of the thermocouple 35 by a conductor 51. A hood 52 is applied over the magnet frame 47 and coil 49 and is spun into engagement with or otherwise attached to the terminal bushing 48.

A stem 54 is mounted for reciprocatory movement through an opening in the inner end of the hood 52. An armature '55 is mounted for relative movement on the inner end of the stem 54 to permit self-accommodation to the pole faces of the magnet frame 47. A valve disc 56 is mounted for relative movement on the outer end of the stem 54 for self-accommodation to an annular valv seat 57 at the inner end of the outlet port 4. A coiled spring 58 is interposed between the hood 52 and a radial flange or abutment '59 on the valve stem 54, and moves the valve disc 56 to closed position against the valve seat 57 upon cessation of thermoelectric energization of the electromagnet comprising the magnet frame 47 and coil 49, for example, upon extinguishment of the pilot burner flame.

For the purpose of cooking or resetting the valve member 56 to open position and the armature 55 to attracted position and, at the same time, shunting the magnetic flux away from the armature 20' of the operator 28 to prevent opening of the valve member 23' during the cocking operation, a lever 60 is pivoted at 61, for example, on an extension of the common pole piece 32. One end of the lever 60 is positioned for engagement with the passing through the core posts 29, pole pieces 31 and 32, I

and through the magnetic shunt constituted by the lever 60. As a result the valve member 23 is effectively prevented from being opened by thermoelectric energization of the operator 28 during the cocking operation. And this is accomplished without physically contacting the valve mechanism or related parts.

Where the energization of the electromagnet, comprising the magnet frame 47 and coil 49while sufficient to hold the armature 55 in attracted position and the valve member 56 in open positionis insufficient to move the armature 55 to attracted position and the valve member 56 to open position, a manual reset or cocking button 65 may be provided.

The reset button 65 is carried by the outer end of a reset stem 68 which has reciprocatory movement through the wall of the control body 1, for example, in a sealing bushing shown more or less diagrammatically at 69. The inner end of the stem 68 is connected at 70 to the pivoted magnetic shunt lever 60. When the button 65 is depressed, the connection 70 swings the lever 60 counterclockwise about its pivot 61. During this movement the lever 60 engages the abutment 59 and moves the armature 55 to attracted position and the valve member 56 to open position.

The depression of the button 65 also moves the magnetic shunt lever 60 into contact or engagement with the pole extensions 62 of the thermoelectrically powered electromagnet operator 28. As previously described, this shunts magnetic flux established by thermoelectric deenergization of the operator 28 away from the armature 20', and, as a result, the valve member 23 is effectively prevented from being opened by thermoelectric energization of the operator 28 during the cocking operation.

Terminal connector means is shown more or less diagrammatically at for connecting the lead conductor means of the thermocouple 35 in circuit with.the coil 49.

Where the condition-responsive means 44 is in the form of, or includes, a thermostat, a temperature selecting or adjustment knob 82 may be provided on the outside of the control body 1 for adjusting the temperature at which, for example, the thermostat contacts (not shown) sep arate. The thermostat may be of the flexible bellows type with enclosed solid or hard contacts and with the space within the bellows in communication with a remotely disposed bulb (not shown) through a capillary tube indicated fragmentarily at 83 in Figure 2. When the reset button 65 is released following the resettingor each '0, "a coiled spring 75 returns button 65 and stem .68 totheir outwardly projecting positions; also the magneticshunt lever 60 to its full :line position as shown in Figure l. The cocking and magnetic shunting position of the lever 60 is shown in dotted lines in Figure 1.

Operation To place the control in operation, the gas cock is turned to the On position, and the reset button 65 is depressed. This causes the stem 68 to swing the lever 60 in a direction to move the valve member 56 to open position and the armature 55 to attracted position. This allows gas to flow to the pilot burner 18 which, when ignited, heats the hot junction 38 of the thermocouple $5.

When the pivoted shunt lever 60 contacts the pole piece extensions 62, the magnetic flux established by thermoelectric energization of the operator 28 is shunted away from the armature 20', and the valve member is thus prevented from being opened by thermoelectric energization of the operator 28 during the cocking operation.

When the electromagnet, comprising the magnet frame 47 and coil 49, is thermoelectrically energized and holds the armature 55 in attracted position and the valve member 56 in open position, the cocking button 65 is released. This moves the magnetic shunt lever from its shunting position to the position shown in full lines in Figure 1 and the thermoelectrically powered electromagnet op erator may now automatically operate the valve 23 responsive, for example, to the temperature in the space of a space heater, or to the temperature of the water of a Water heater. 7

When the flame of vthe pilot burner 18 is extinguished, the armature 55 is released and valve member 56 moves to closed position which shuts off the flow of gas to the pilot burner. v

The embodiment of the invention shown in the drawings is for illustrative purposes only, and it is to be expressly understoodthat said drawings and the accompanying specification are not to be construed as a definition of the limits or scope of the invention, reference being had .to the appended claims for that purpose.

I claim:

1. Control apparatus for fluid fuel burning apparatus comprising, in combination, first control means biased toward one position and movable toward another position, a thermoelectric generator subject to the heat of burning fuel, a thermoelectrically powered operator for said first control means comprising an armature connected to said control means and an electromagnet in circuit with said generator cooperating with said armature and adapted when thermoelectrically energized to attract said armature and move said control means to said other position against said bias, second control means having first and second positions, holding means for holding said second control means in said first position when moved thereto, and reset means for resetting said second control means to its said first position comprising a manually movable member cooperable with said second control means and having a magnetic shunt portion operable by manual acmotion of said reset means to a position wherein it shunts magnetic flux of said electromagnet away from said armature to thereby afford means external to the thermoelectric circuit of said electromagnetic operator rendering the latter incapable of positioning said first control means in Said other position during a resetting operation despite possible energization of said operator by current from said generator during said resetting operation.

2. Control apparatus for fluid fuel burning apparatus comprising, in combination, a first flow controlling member biased toward a flow-preventing position and movable toward a flow-permitting position, a thermoelectric generator subject to the heat of burning fuel, a thermoelectrically powered operator for said first flow controlling member comprising an armature connected thereto and 6 an electromagnet in circuit withsaid generator cooperating'with'zsaid armature and adapted when thermoelectrie cally energized to attract said armature 'and move sait'l flow controlling member to flow-permitting position against said bias, a second flow controlling member hav.- ing flow-preventing and flow-permitting positions, holding means for holding said second flow controlling member in 1 flow-permitting position when moved thereto, and reset and flow interrupter means forfresetting said second flow controlling member to flow-permitting position compris ing a manually movable reset member cooperable with said second flow-controlling member and having a magnetic shunt portion operable by manual actuation of said reset member to a position wherein it'shunts magnetic flux of said electromagnet away from said armature to thereby afford means external to the thermoelectric circuit of said electromagnetic operator rendering the latter incapable of positioning said first flow-controlling member in fiow-permittingposition during a resetting operation despite possible energization of said operator by current from said generator during said resetting operation. a

3. Control apparatus for fluid fuel burning apparatus comprising, in combination, first control means biased toward one position and movable toward another position, a thermoelectric generator subject to the heat of burning fuel, a thermoelectrically powered operator for said first control means comprising an armature connected to said control means and an electromagnet in circuit with said generator having pole pieces cooperating with said armature and adapted when thermoelectrically energized to at tract said armature and move said control means to said other position against said bias, second control means having first and second positions, holding means for hold-' ing said second control means in said first position when moved thereto, and reset means for resetting said second control means to its said first position including a manually movable pivotally mounted reset lever having a magnetic shunt portion swingable by manual actuation of said reset lever into flux-shunting relation with respect to said electromagnet pole pieces to shunt magnetic flux of said electromagnet away from said armature and thereby afford means eirtemal to the thermoelectric circuit of said electromagnetic operator rendering the latter incapable of positioning said first control means in said other position during a resetting operation despite possible energization of said operator by current from said generator during said resetting operation.

4. Control apparatus for fluid fuel burning apparatul comprising, in combination, a first flow-controlling mem-' ber biased toward a flow-preventing position and movable toward a flow-permitting position, a thermoelectric generator subject to the heat of burning fuel, a thermoelectrically powered operator for said first flow-controlling member comprising an armature connected thereto and an electromagnet in circuit with said generator having pole pieces cooperating with said armatme and adapted when thermoelectrically energized to attract said armature and move said flow-controlling member to flow-permitting position against said bias, a second flow-controlling member having flow-preventing and flow-permitting posi-" tions, holding means for holding said second flow-controlling member in flow-permitting position when moved thereto, and reset and flow interrupter means for resetting said second flow-controlling member to flow-permitting position including a manually movable pivotally mounted reset lever having a magnetic shunt portion swingable by manual actuation of said reset lever into flux-shunting relation with respect to said electromagnet pole pieces to shunt magnetic flux of said electromagnet away from said armature and thereby afford means external to the thermoelectric circuit of said electromagnetic operator rendering the latter incapable of positioning said first flow-controlling member in flow-permitting position during a resetting operation despite possible energiza- "7 tion of sald operator by current from said generator during said resetting operation,. and cooperable abutment nieans on said reset lever and said second flow-controlling member operable to move the latter to flow-permitting position and into holding cooperation with said holding means on movement of said shunt portion into magnetic engagement with said pole pieces.

. 5. Control apparatus for fluid fuel burning apparatus having a main burner and an ignition burner comprising, in combination, a first valve member having an open position for flow of fuel to said main burner and biased toward a closed position shutting ofi the flow of fuel to said main .burner, a thermoelectric generator subject to the heat of burning fuel, a thermolectn'cally powered electromagnetic operator in circuit with said generator and normally operative when energized by current from said generator to actuate said first valve member toward open position, a second' valve member having an open position for flow of fuel to said ignition burner and biased toward a closed position shutting off the flow of fuel to said ignition burner, holding means for holding said second valve member in open position when moved thereto, reset. and flow interrupter means for resetting said second valve member to open position and into holding cooperation with said holding means comprising a manually movable reset member cooperable with said second valve member and having a magnetic shunt portion operable by manual actuation of said reset member to an operative position wherein it shunts magnetic flux of said operator to thereby atford means external to the thermoelectric circuit of said electromagnetic operator rendering the latter incapable of positioning said first valvein open position, whereby to insure during a resetting operation closureof said first valve member under its bias and shut off of the fuel flow to said main burner despite possible energization of said operator by current from said generator during said resetting operation.

6. In a combination fuel flow control device for fluid fuel burning apparatus of the class wherein a main fuel flow-controlling member is capable of being cycled by a thermoelectrically powered cycling type electromagnetic operator energized by current from a thermoelectric genorator subject to the heat of burning fuel, and an ignition fuel flow-controlling member is held in flow-permitting position by holding means when moved thereto, the combination with said ignition fuel flow-controlling member and: electromagnetic operator of manually operable means external to the thermoelectric circuit of said operator for resetting said ignition fuel flow-controlling memher to flow-permitting position and for insuring that the main fuel flow-controlling member is in flow-preventing position during a resetting operation, said means comprising a manually movable member cooperable with said ignition fuel flow-controlling member and having a magnetic shunt portion actuated by manual actuation of said manually operable'means to an operative position wherein it shunts magnetic flux of said operator to render the latter incapable of positioning said main fuel flow-controlling member in a flow-permitting position during a resetting operatiorr despite possible energization of said operator by current from said generator during said resetting operation. v

7. Control apparatus for fluid fuel burning apparatus comprising, in combination, first control means biased toward one position and movable toward another position, a thermoelectric generator subject to the heat of burning fuel, a thermoelectrically powered operator for said first control means comprising an armature connected to said control means and an electromagnet in circuit with said generator cooperating with said armature and adapted when thermoelectrically energized to attract sa'id armature and move said control means to said other position against said bias, 'second control means having first and second positions, electromagnetic holding means also in circuit with said thermoelectric generator and energized thereby for holding said second control means in said first position when moved thereto, and reset means for resetting said second control means to its said first position comprising a manually movable reset member cooperable with said second control means and having a magnetic shunt portion operable by manual actuation of said reset member to a position wherein it shunts magnetic flux of said electromagnet away from said armature to thereby afford means external to the thermoelectric circuit of said electromagnetic operator rendering the latter incapable of positioning said first control means in said other position during aresetting operation despite possible energization of said operator by current from said generator during said resetting operation.

.8. Control apparatus for fluid fuel burning apparatus having a main burner and an ignition burner comprising, in combination, a first valve member having an open position for flow of fuel to said main burner and biased toward a closed position shutting off the flow of fuel to said main burner, a thermoelectric generator subject to the heat of burning fuel at said ignition burner, a thermoelectrically powered electromagnetic operator in circuit with said generator and normally operative when energized by current from said generator to actuate said first valve member toward open position, a second valve member having an open position for flow of fuel to said ignition burner and biased toward a closed position shutting off the flow of fuel to said ignition burner, electromagnetic holding means for holding said second valve member in open position when moved thereto, said holding means also being connected in circuit with said gen erator for energization thereby, reset and flow interrupter means for resetting said second valve member to'open position and into holding cooperation with said holding means comprising 7 a manually movable reset member cooperable with said second valve member and having a magnetic shunt portion operable by manual actuation of said reset member to an operative position wherein it shunts magnetic flux of said operator to thereby afford means external to the thermoelectric circuit of said electromagnetic operator rendering the latter incapable of positioning said first valve in open position, whereby to insure during a resetting operation closure of said first valve member under its bias and shut off of the fuel flow to said main burner despite possible energization of said operator by current from said generator during said resetting operation.

References Cited in the file of this patent

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