US2372506A - Thermoelectric safety device - Google Patents

Description

' fuel to the burner.

Patented Mar. 27, 19 45 I 2,372,506 THERMOELECTRIC SAFETY nnvrcn Harold A. Mantz, Milwaukee, Wis., assignor to Milwaukee Gas Specialty company Miiwaukee, Wis., a corporation of Wisconsin Original application June 24, 1939, Serial No. 280,921.- Divided and this application Novem: ber 10, 1941, Serial N0. 418,443

8 Claims.

This invention relates to thermoelectric safety devices for heating and other apparatus, and has particular relation to an improved thermocouple The side of the valve body I opposite the plug or capmember 22 has an opening 24 exor thermoelectric generator and pilot burner for devices of the character set forth.

The present application is a division of my .copending application Serial No. 280,921, filed June 24, 1939.

One of the mainobjects of the present invention is to provide an improved form of combined thermocouple or thermoelectric generator and pilot burner which is eflective and reliable in operation and, at the same time, is simple and compact in construction and relatively inexpensive to build, assemble, and install; also an improved lead connection arrangement for the thermocouple.

. Further objects and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawing, in which:

Figure 1 is an axial section through a thermoelectric valve showing a thermocouple and pilot burner embodyingthe present invention applied thereto; and

Figure 2 is a side view of the thermoelectric valve and thermocouple and pilot burner shown in Figure 1.

Referring to the drawing, the device selected for illustration comprises a, valve body In having a fuel inlet II and a fuel outlet l2 which are tapped internally to receive the inlet and outlet pipe sections of the fuelsupply pipe leading to the main burner (not shown). The valve body l0 has an internal wall or partition [3 which has a valve opening I through which communication is adapted to be efiected between the inlet chamber l5 which is in communication with the inlet l l, and the outlet chamber l6 which is in communication with the outlet l2. The valve opening I 4 is surrounded bya valve seat I8.

Communication between the inlet chamber l5 and the outlet chamber it through the valve opening I 4 is controlled by a valve disc 20. The

- valv disc 20 is adapted to seat against the valve seat is to close communication between chambers I 5 and IB and thereby to shut ofi the fuel supply to the main bumer. Movement of the valve disc 20 away from the valve seat Hi to open position, as shown, sets up The valve disc 20 may have a valve disc gasket or yielding seating member (not shown) suitably secured thereto for yielding seating engagement with the seat 3, although this may vary- A plug or cap member 22 is detachably secured, for example, by threaded engagement, as shown, to the valve body I lJ-in alignment with the valve 20,.and a valve closing and armature retracting spring 23 is interposed between the valve disc 20 and the cap member 22.

the desired supply of tending therethrough also in alignment with the axis of the valve 28, and secured in this opening 24, for example, by threaded engagement therein, as shown, is a post 25 formed of metal or other suitable material, which post 25 has an opening 26 extending axially therethrough. A frame 28, formed of metal or other suitable material, has an inner wall 29 disposed radially of the post 25 and clamped in place. to the valve body ill, for example, byeengagement of the shoulder 30 on the plug 25 therewith, as shown. The frame 28 has an annular wall 32 integral with the wall 29.

Either the outer end of the post 25 or the annular wall 32, or both, and preferably at least the outer end of the post 25, constitutes a magnet frame or core for the electromagnet. The

electromagnet coil means is shown in the form of a pair of ribbon-like conductors surrounding or coiled at 36 about the post 25 and disposed terminals 38 from the frame 28 adjacent the opening 40, and the inner terminals of the coils 36 are connected together by suitabl conductor means or grounded, for example, through the post 25 to connect the coils 36 in series circuit relation.

The armature is disposed externally of the 'valve body and on the side of the electromagnet 'oppositethe side on which the valve or control member 20 is disposed. The armature, which is shown as of disc-like form and as secured to the outer end of a recip'rocatory armature and valve stem 46, is adapted to be held attracted to the magnet frame of the electromagnet when the electromagnet is energized by the heat of the pilot burner on the thermocouple. The attachment of the armature to thestem 46 may, if desired; be of a character -to permit some selfaccommodation of the armature to the polemeans of the magnet frame when the armature is in attracted position.

The stem 46 extends inwardly for reciprocatory movement through the opening 26 in the post 25'. and its inner end engages at 48 axiallyin a recess in the valve disc 20. A-reset button 50 may be secured upon the outer end of the stem 46. The opening 26 may, of course, be sealed, as suitable or desired, against leakage of the gas or other fuel out through the opening 26 along the stem nection to the "II, and when is mounted, for instance, by threaded engagement at 62 upon the outer end of the tube 53 which supplies fuel to the pilot humor. The opposite end of the pilot supply tube 63 is connected to the fuel through connection at 64 to the outlet chamber of the valve body l0. Ametering screw may be provided at 65 for metering the supply of fuel for the pilot burner.

If, because of the greater amount of fuel outlet opening at the main burner, the pilot supply contube 63, at 64, does not supply the supply line, for example,.

- shutting off the supply desired pilot supply of fuel to the pilot burner from the outlet chamber l8 when the valve 2. is open,.the pilot supply tube may be connected to the fuel supply line in any'other suitabl or preferred manner to secure the desired pilot supply of fuel to the pilot burner when the valve 20 is open. For example, the tube 83 may be connected to the fuel supply line anterior of the valve body ill, or it may be connected to the valve body in communication with the inlet chamber I5, or any other suitable connection may be provided for supplying fuel to the pilot supply'tube 63.

The thermocouple comprises a pair of thermocouple elements 68 and formed of any desired dissimilar metallic materials. In the illustrated embodiment of the invention, the thermocouple elements 68 and 69 are in-the form of flat strips secured by screws I0 to the insulating base of the pilot burner 60. The outer ends of the thermocouple elements 68 and 6! are bowed inwardly at 12, and terminate in parallel for example, through a suitable intervening element I! to form a "hot junction at 18 in ali nment with the opening or port 18 through the pilot. head '80. Theintervening element is referably of good heat conveying or heat conducting char'acteristics adapted for picking up and conveying the heat to the junction I! when the pilot light is burning. and heat to cool the junction 15 when the pilot flame is extinguished.

Metallic lead conductors as shown in the form of flat strips or of ribbon-like form, although this may vary within the scope tion, are connected at their inner ends at I to the terminals 30 of the respective coil portions 36. The outer ends of the lead conductors ll are 82 to the inner ends thermocouple elements it and connected through terminals of the respective 69, "cold thermocouple junctions being provided in juxtaposition to the connections between the conductors ti and therespectlve thermocouple elements. a

where the fuel is of a character, such as gas, requiring admixture of air therewith, the air necessary to provide the desired gaseous mixture is supplied in any suitable 'or preferred manner. When thevalve 20 is openor, where the pilot burner connection is anterior to this valve, then open or closed, the pilot supply when the valve is mixture or other fuel of. the resulting gaseous through the through the ort ignited, forms the pilot name as uponthe thermal junction 1 which impinges thermoelectric and-heats the same .to set up a current. H

of the prwent inventube '3 t0 the pilot vention, closing of tips H joined. 7

asvas'oe heat of which the thermal junction 16 is subject is extinguished, the electromagnet ls deenergized, or at least the holding action thereof ceases to be suilicient to hold the armature .li attracted to the magnet frame, as shown, and the spring 23 compels the valve 2! to closed position, thereby of fuel to the main burner through the valve opening of the valve 20 to cloud position, the outer end of the stem 4|, by its attachment to the armature 45, moves the armature II to retracted position. In the illustrated embodiment of the inth e valve 2| also shuts oil the supply of fuel to the pilot burner. The particular showing in this 'pect is more or less diagram- .matic and only for urposes of illustration.

when it is desired to reset the device, the reset button II is pressed inwardly. This presses the armature to attracted position and simultaneously presses the valve 20 to open position against the tension of the spring 23. A pilot supply or fuel is thereupon set-up to the pilot burner which is creates a thermoelectric current in the coil means 3i. This energizes the electromagnet and causes the armature to be held positively against the magnet frame or in attracted position and the valve II in open position.

Upon extlnguishment of the pilot time the electromagnet is deenergized, or at least the holding action' thereof ceases to be sufllclent to hold the armature in attracted position and, as previonsly pointed out, the spring 2 3 compels the /valve 2! to closed position, thereby shuttingoif for dissipating the v along the outer 'means and constitutin {said thermocouple elements each other outwardly the supply of fuel and, armature is actuated to retracted position.

I do not intend to be limited to the precise details shown or described.

I claim:

l. A thermocouple and pllot'devlce comprising 7 aninsulating pilot head havin a base and a tip extending from said base, an opening extending through said tip through which fuel is discharged to maintain a pilot flame, said pilot head having an opening for the admission of air. means adjustable on the tip of said pilot head having said head for adiustlng'the air inlet, and a pair of thermocouple elements secured in spaced relation to the base of said head and extending exsides of said adjusting guard means therefor, being bowed toward of said head andioined at their outer ends to form a thermal Junction Box substantially in alignment with said port.

2. A thermocouple and pilot burner comprising ,a refractory insulating pllot'head having an enlargedbase portion and provided with a port through which fuel is adapted to be discharged to maintain a pilot flame, said pilot head being adapted for attachment to a fuel su ply Pipe with said port in communication therewith, said pilot head having a reduced tip part in communication with said port and provided with port means adjacent the base portion of the pilot head for the II. In the movement the heat of the pilot flame upon. the thermal junction II of the thermocouplev at the same time, the I the pilot flame maintained at said tip part, said.

thermocouple elements extending externally along outer sides of said air adjusting nut and constituting guard means therefor.

3. A thermocouple and pilot burner comprising a refractory insulating pilot head having an enlarged base portion and provided with a I port through which fuel is adapted to be discharged to maintain a pilot flame, said pilot head being adapted for attachment to a fuel supply pipe with saidport in communication therewith, said pilot head having a reduced tip part in communication with said port and provided with port means adjacent the base portion of the pilot head for the admission of air, a nut adjustable on said tip part for adjusting said air admission port means, and a pair of thermocouple elements securedin spaced relation to oppositesides of said base portion and brought substantially together and joined at their outer ends to form a thermojunction positioned outwardly of said tip part to be heated by the pilot flame maintained at said tip part, the reduced size of said tip part being suflicient to permit adjustment of said nut between said thermocouple elements, said thermocouple elements extending externally along outer sides of said air adjusting nut and constituting guard means therefor.

4. A thermocouple and pilot burner comprising a refractory insulating pilot head having an enlarged base portion and provided with a port through which fuel is adapted to be discharged to maintain a pilot flame, said pilot head being adapted for attachment to a fuel supply pipe with said port in communication therewith, said pilot head having a reduced tip part in communication with said port and provided with port means adjacent the base portion of the-pilot head for the admission of air, a nut adjustable on said tip part for adjusting said air admission port means, a pair of thermocouple elements secured in spaced relation to opposite sides brought substantiall together and joined at their outer ends to form a thermojunction positioned outwardly of said tip part to be heated by the pilot flame maintained at said tip part, and a pair of lead conductors secured to opposite sides of said pilot head, one in contact with each of said thermocouple elements, said thermocouple elements extending externally along outer sides of said air adjusting nut and constituting guard means therefor.

5. A thermocouple and pilot burner comprising a refractory insulating pilot head having an enlarged base portion and provided with a port through which fuel .is adapted to be discharged to maintain a pilot flame, said pilot head being adapted for attachment to a fuel supply pipe with said port in communication therewith, said pilot head having a reduced tip part in communication with said port and provided with port means adjacent the base portion of the pilot head for the admission of air, a nut adjustabl on said tip part for adjusting said air admission port means, a pair of thermocouple elements secured in spaced relation to opposite sides of said base Portion and brought substantially together and joined at their outer ends to form a thermojunction positioned of said base portion and v opposite sides of said base portion spaced apart 7 pilot flame maintained at said tip part, the reduced size of said tip part being suiiicient to permit adjustment of said nut between said thermocouple elements, a pair of lead conductors secured to opposite sides of said pilot head, one in contact with each of said thermocouple elements, and an intervening element secured between the joined ends of said thermocouple elements at the thermojunction heated by the pilot flame, said thermocouple elements extending externally along outer sides of said air adjusting nut and constituting guard means therefor.

6. A thermocouple and pilot burner comprising a refractory insulating pilot head having an en'- larged base portion and provided with a port through which fuel is adapted to be discharged to maintain a pilot flame, said pilot head being adapted for attachment to a fuel supply pipe with said port in communication therewith, said pilot head having a reduced tip part in communication with said port and provided with port means adjacent the base portion of the pilot head for the admission of air, a nut threaded on said tip part for adjusting said air admission part means and a pair of thermocouple elements secured to and insulated from each other thereby and brought substantially together and joined at their outer ends to form a thermojunction positioned outwardly of said tip part to be heated by the pilot flame maintained at said tip part, the reduced size of said tip'part being suflicient to permit adjustment of said nut between said thermocouple elements.

7. A thermocouple and pilot burner comprising a refractory insulating pilot head having an enlarged base portion and provided with a port through which fuel'is adapted to be discharged to maintain a pilot 'flame, said pilot head being adapted for attachment to a fuel supply pipe with said port in communication therewith, said pilot head having a reduced tip part in communication with said port and provided withport means adjacent the base portion of the pilot head for the admission of air, a pair of thermocouple elements secured to opposite sides of said base portion spaced apart and insulated from each other thereby and brought substantially together and joined at their outer ends to form a thermojunction positioned outwardly of said tip part to be heated thermocouple elements, and an intervening element securedbetween the joined ends of said thermocouple elements at the thermojunction heated by the pilot flame.

8. A thermocouple and pilot device comprisinga pair of thermocouple elements each of flat ribhon-like form having angular tips joined to form athermojunction, said thermocouple elements be.

ing bowed apart inwardly of said tips to form a space therebetween, an insulating pilot tip posi tioned between the spaced apart ends of said thermocouple elements and having an outlet directed toward said thermojunction, and means passing laterally through the spaced apart ends of said thermocouple elements and into the base outwardly of said tip part to be heated by the is 'of the tip for securing said tip in place between said thermocouple elements.

v HAROLD A sum.

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