US2359921A - Safety pilot device - Google Patents

Description

W. H. KLIEVER SAFETY PILOT DEVICE Filed Jan. 24, 1942 v INVENTOR r m Q 1 1 K H O n m ATTORNEY Patented Oct. 10, 1944 UNITED STATES PATENT OFFICE SAFETY PILOT DEVICE Application January 24, 1942, Serial No. 428,095

17 Claims.

The present invention relates to a thermomagnetically actuated rotatable fluid control means and in particular to a valve for controlling the flow of fuel for a. burner. A further object of the invention is to provide a safety valve that is biased to a. first position and which is magnetically operated to a second position by novel rotatable valve actuating means under the control of a thermomagnetic or Curie point member. The thermomagnetic member is of a materialthat is magnetic when maintained at a temperature below the Curie point or critical temperature value and non-magnetic in the range of temperatures above this value and to which the member is subjected for indicating the existence of a burner flame.

One particular object of my invention is to provide a fluid regulating means controlled by a Curie point control member wherein an armature is directly associated with the fluid regulating, means and rotatably actuated with respect to a magnet and in which the thermomagnetic control member regulates a magnetic shunt to control the operation of the armature.

In general, the invention relates to the provision of a novel safety pilot burner of the type disclosed in the application of Frederick E. Lange, Serial No. 385,426, filed March 27, 1941, now Patent No. 2,299,155, granted October 20, 1942, wherein the Curie point control member when. varied with respect to the critical temperature thereof regulates a magnetic shunt to vary the operation of an armature and associated valve means.

In accordance with, a particular feature of the invention, the armature is rotated together with transmission means for the operation of a counterbalanced and biased valve by the application of a magnetic force, as distinguished from the application of a sufficient magnetic force to provide for the vertical and lifting movement of the armature and valve as disclosed in the prior art.

In one embodiment of my invention the magnet is employed as the armature for rotation with respect to the Curie point material which controls the operation of the valve.

An additional feature of my invention is the use of an extended flexible transmission means which is protected from influence by the burner flame and prov'des for the remote operation of the valve by the temperature sensitive means. .Also a novel frictionless bearing is provided for supporting the transmission shaft in a biased position and the valve casing houses a novel frictionless and counterbalanced means for supporting the shaft and for transmitting the rotational movement of the shaft to the valve operating means. In keeping with my invention, the trans mission means may consist of a shaft or flexible connecting means housed in a tube or cable and supported by the frictionless bearing and by the frictionless valve actuating biasing and shaft supporting means.

Additional objects of the invention will become apparent from a consideration of the accompanying specification and drawing:

Figure 1 is a vertical View partly in section embodying the thermomagnetic safety valve of my invention,

Figure 2 is a plan view taken along the line 2-2 of Figure 1 and also illustrates the application of a pilot burner flame to the thermomagnetic responsive member,

Figure 3 is a plan view, partly in section and taken along the lines 33 of Figure 1,

Figure 4 is a plan view taken along the lines 4- l of Figure 1, and

Figure 5 is a plan view partly in section of the valve taken along theline 55 of Figure 1.

Referring to the drawing, a safety valve referred to generally by the reference numeral Ill is employed to control the flow of gas to burners of the type that maybe employed with stoves, ovens, or for general heating applications. The gas supply line, not shown, is secured to the end I l of the valve casing, and the valve controls the flow of gas from the outlet end l2 of the valve casing to the burner fuel line, not shown, The valve H) is actuated by an elongated rotatable shaft I 5 which is housed in the conduit or tubing [6 and a flexible shaft and conduit may be employed, if desired. The transmission shaft is accordingly housed and protected by the tubing i6 and the elongated shaft provides for the remote operation of the valve by the thermomagnetic member hereinafter described.

The upper end of the shaft 15 is secured to one outer side of a U shaped bracket member I! and a steam l3 supporting armature I9 is secured to the other outer side portion of the U shaped bracket member. A casing member 20 secured to the upper end of the tube I6 serves to house the bracket member ll. Mounted securely within the casing 29 is a friction snap ring 22 illustrated in Figures 1 and 4. This ring consists of a first segment 22 and a snap ring portion 23 which cooperates therewith. Mounted upon ears 25 and 25 secured to the bracket H are the end portions of a spring consisting of a flexible metallic reedl ke me ber 21, The arms of the reed-like member 21 extend at substantially right angles to each other and the center portion of this member is supported by the housing 20 to which it is secured by the snap spring member 23. The arms of the reed-like member 21 secured to the bracket I! serve as a support and frictionless bearing for the rotatable shaft l5. The two arms of the spring member are free from contact with other surfaces and upon rotation of the shaft by the armature these arms are flexed to thus serve as a frictionless bearing in addition to supporting the shaft in a biased position.

The armature I9 is enclosed in the inverted cup shaped casing 33 and a gasket 34 is mounted between the flared end portions of the casing members 20 and 33 to provide a seal. The gas is permitted to flow through the tube I6, and accordingly the armature and transmission shaft are maintained at substantially the temperature of the gas.

In the preferred embodiment of my invention a permanent magnet 40 is supported between the leg portions 4| and 42 of the inverted U shaped member 43 as shown in Figure 1. The member 43 includes a cross-member 44 which consists of a thermomagnetic material that is capable of conducting magnetic flux only when maintained at a temperature below the critical or Curie point value, A material is selected for the member 44 that has a Curie point below the range of temperatures of a burner flame. This material is also known as Curie point material. The leg portions 4| and 42 of the member 43 are constructed of a magnetic conducting material and the end connecting member 44 of Curie point material is secured to the leg portions in any well known manner. The lower ends of the members 4| and 42 may be welded or otherwise secured to the armature casing 33 and the permanent magnet 40 and the ends of the members 4| and 42 are enclosed in the Z shaped housing member 46. The lower end portion of the casing member 46, as illustrated, fits closely over the armature casing member 33 and is secured to the flared and rolled edge portion of the bearing casing member 20.

The armature I9, as illustrated in Figure 3, is in the unattracted and biased position assumed when the Curie point material is at a temperature below the critical value and accordingly capable of conducting magnetic flux. At this time the Curie point material 44 and the arms 4| and 42 serve as a shunt for the magnetic flux of the permanent magnet and prevent the flux from attracting and rotating the armature l9. The Curie point member 44 when employed as a safety burner device is rendered responsive to the temperature of a pilot burner flame or other burner flame, as illustrated in Figure 2. In response to the relatively high temperature indicative of the existence of the burner flame, the thermomagnetic member 44 is raised above the critical or Curie point value thereof and no longer is capable of conducting the magnetic flux. The shunt is accordingly removed and a magnetic circuit is established from the permanent magnet through the lower end portions of the members 4| and 42 and the armature to attract and cause the rotation of th armature IS.

The transmissionshaft 5 which is actuated by the armature |9 is secured at the lower end thereof to a bracket 50, as shown in Figures 1 and 5. Mounted within the housing of the valve generally indicated by the reference character I is a plate or bracket member which is retained therein againsta raised inner surface portion of th valve by the snap ring member 52. One end of a flat reed. spring member 53 is secured to the bracket member 5| and the extended portion of this spring is secured to the bracket 50. Also mounted upon the extended end of this spring member is the rigid arm 54, the other end of which extends below the seat of the valve and supports thereon a counterweight 55 and a flexible valve stem member 56. A self sealing valve disk member 5! is supported at the upper end of the flexible valve stem. A plug member 60 is threadedly secured to the side of the valve casing at a point directly above the valve disk, as illustrated in Figures 1 and 5. The valve 0 is threadedly secured to the tub 6 and a set screw or other means, not shown, may be employed to prevent relative movement between the tube l6 and the valve.

A counterweight, or counterweights, 6| may be secured to the outer end of the bracket 50 to which the transmission shaft is secured. The valve as shown in Figures 1 and 5 is in the closed position to which it is biased by operation of the bearing member I! of the transmission shaft l5 and by the valve actuating spring 53. The spring 53 may be so adjusted as to determine the force required to operate the valve, also to provide a bias which is opposed to the magnetic operating forces and this combination eliminates backlash in the coupling between the valve operating parts. In response to the existence of the pilot burner flame and the relatively high temperature resulting therefrom the shunt otherwise maintained by the Curie point member 44 is removed and the armature rotates the transmission shaft against the bias provided by the bearing H and spring 53. The lower end portion of the transmission shaft |5 rotatably operate through the bracket member 50 to flex the extended end of the frictionless bearing member 53 and actuate the valve to an open position. Upon extinguishment of the burner flame the temperature of the Curie point material is rapidly lowered below the critical value and the magnetic shunt is again established from the permanent magnet through the members 4| and 42 to the Curie point mate rial 44. The armature I9 is accordingly no longer attracted by the magnet and the bearing l1 and spring 53 rotate the armature and shaft to .the biased position which serves to close the valve.

In modified form my invention is so constructed as to combine the magnet and armature into a single element and the inverted U shaped member 43 is constructed entirely of thermomagnetic or Curie point material. Thus, the armature I9 is constructed of a permanently magnetic material and the permanent magnet 40 is dispensed with. The valve is biased to the op n position. The combined armature and magnet member is attracted to the thermomagnetic member 43 against the bias of the valve when the thermomagnetic member 43 is below the critical or Curie point temperature value to thus retain the valve in closed position. When the thermomagnetic material is heated to a temperature above the Curie point value indicative of the presence of the pilot burner flame to which it is exposed, this member will no longer attract the magnetic armature and the armature will be rotated by the biasing means in a manner to open and retain the valve in open position. However, upon extinguishment of the burner flame the thermomagnetic member 43 will rapidly coolt tem perature below the Curie point value and the Curie point member 43 will again attract the magnetic armatur l9 to rotatably actuate the valve to'the closed position.

In the modified form, my invention does not employ a shunt circuit for the magnetic flux although it does employ the feature of rotating the armature and transmission means for regulation of the valve under the control of the Curie point material.

In accordance with both forms of my invention, it will be noted that the novel combination of the spring bearing and support member, rotatable transmission, and valve, or other means controlled thereby may be employed to advantage in conjunction with sensitive control members of various types. The advantageous application of my invention with reference to the provision of a flexible, elongated and rotatable transmission means for the remote operation of a valve or other controlled member by a sensitive controlling means will likewise be apparent to those skilled in the art.

Of particular importance is the adaptation of the safety gas valve devices constructed in accordance with the embodiments of my invention disclosed above for use in any desired position. The devices may accordingly be employed to advantage, for example, in the control of stoves and ovens without the necessity of maintaining the valve and armature means in a vertical position such as required by known devices of the prior art. Furthermore, due to the fact that slight changes in length of the rod due to thermal expansion do not affect the operating relation between the armature and the valve, the control device of the present invention can be employed where it is subjected to substantial changes in temperature without affecting its operation. It will further be apparent that the thermomagnetic control member employed in my invention may be adapted to respond to temperatures produced by means other than burner flames and, for example, may be operated in conjunction with the controlled operation of an electrical heating means associated therewith. Thus, it is believed obvious that the thermomagnetic sensitive controller may be adapted to respond to furnace and other temperatures by the proper selection of the Curie point material.

It is apparent that various modifications of the embodiments of my invention described above may be made, and accordingly it is to be understood that the invention is limited only by the scope of the appended claims.

I claim as my invention:

1. A safety device for a fluid fuel burner comprising in combination, a valve casing, elongated valve actuating means, said means including a magnet and an armature member biased to one position and rotatable against said bias by operation of the said magnet, means for providing a gas tight seal between the valve casing and a portion of the valve actuating means, means for bridging the magnet to provide a shunt of the magnetic flux from the said armature, the said bridging means including therein at least a pertion of Curie point material for operation as the material is varied in temperature to control the magnetic shunting operation of the bridging means and to accordingly control the rotation of the armature of the valve actuating means.

2. A safety device for a fluid fuel burner comprising in combination, a valve casing, valve actuating means, said means including a magnet and an armature member biased to one position and rotatable against said bias by operation of the said magnet, means for bridging the magnet to provide a shunt of the magnetic flux from the said armature, the said bridging means including therein at least a portion of Curie point material for operation as the material is varied in temperature to control the magnetic shunting operation of the bridging means and to accordingly control the rotation of the armature of the valve actuating means.

3. A combination comprising fluid flow control means rotatable to control flow and biased to a first fluid control position, said means including magnet and armature means for rotating the control means to actuate and hold said control means to a second fluid control position, and a member of Curie point metal associated with the said magnet and armature means for actuation upon temperature variation of said metal with respect to the critical value thereof to control the operation of the fluid flow control means.

4. A mechanism in combination comprising, rotatable fluid control means biased to fluid flow preventing position and rotatable actuating means therefor, a magnetic member and a member of Curie point metal rotatable with respect to each other with the rotatable member operating the said rotatable fluid control means, said other member being fixed in relation to said fluid control means, and the said member of Curie point metal controlling the operation of the said rotatable fluid control means as it is varied in temperature with respect to the critical temperature thereof.

5. A mechanism in combination comprising rotatably actuated fluid control means biased in one fluid controlling position and including a magnetic member and a Curie point member, one of 'sa d magnetic and Curie point members being rotatable with respect to the other which is fixed in relation to said fluid control means, and one of said members bein associated with said fluid control means for the actuation thereof in accordance with the movement of said one member with respect to the other of said members as the temperature of the Curie point member is varied with respect to the critical temperature thereof.

6. A safety valve for a fluid fuel burner in combination comprising rotatably actuated fluid control means biased to a position preventing the flow of fuel, said means including a magnetic member and a Curie point member, one of said magnetic and Curie point members being movable with respect to the other which is fixed in relation to said fluid control means, and one of said members being associated with said rotatable fluid control means for the actuation thereof in accordance with the movement of said one member with respect to th other as the temperature of the Curie point member is varied with respect to the critical temperature thereof.

7. A safety mechanism comprising fuel control means actuated by rotatable means biased to fuel flow preventing position, said rotatable means including armature and magnet means for rotating the control means to operate and hold said control means in a fuel supply permitting position, a temperature responsive controlling member of Curie point material associated with said magnet and armature means for controlling the flux of said magnet and armature means for operation of the fuel control means, and means associated with said armature for operation of the fuel flow control from a position remote from the temperature responsive controllin member.

8. A safety mechanism comprising fuel control means actuated by rotatable means biased to fuel flow preventing position, said rotatable means including armature and magnet means for rotating the control means to operate and hold said control means in a fuel supply permitting position, a temperature responsive controlling member of Curie point material associated with said magnet and armature means for controlling the flux of said magnet and armature means for operation of the fuel control means, an elongated shaft associated with said armature for operation of the fuel flow control from a position remote from the temperature responsive controlling member, and a conduit for housing the said shaft.

9. A device in combination comprising, a valve casing, a valve seat, a self-aligning valve member, a bracket member in said casin and flexible reed spring means secured at one end to said bracket, an element secured to said reed spring means and connected at one end to a valve op erating member, the said element being counterbalanced at the other end thereof for adjustment of the force required to operate the valve member, and the said flexible member serving as a combination friction free bearing and means for biasing the valve to a first position, and means associated with said flexible means for the actuation of said valve.

10. A combination comprising a shaft, means including a first flexible blade arm supported at one end by a supporting means and having the other end thereof operably associated with the said shaft, a second flexible blade supported at one end by said supporting means and having the other end operably associated with the said shaft, the first flexible blade being mounted to extend at substantially right angles to the second flexible blade, the said flexible members pro viding supporting means for the shaft and for the friction free and limited rotational movement thereof, a valve associated with said shaft for actuation in response to the rotational movement thereof and the said flexible shaft supporting members serving as means for biasing the valve, and control means for rotating the shaft for regulating the operation of the valve.

11. A device in combination comprising, a casing and flow control means therein, a bracket in said casing, flexible reed spring means secured at one end to said bracket, a member connected at one end to the extended portion of the spring means and at the other end to the flow controlling means, a rotatable shaft associated with said spring means for flexing the said extended end portion of the spring means to operate the said flow control means, means including at least two flexible blades secured to supporting means and having the ends thereof disposed for operation with said shaft, at least one of said blades extending from the supporting means at substantially right angles from the positioning of a second blade, th said flexible blades providing for the support of the said shaft and also providing for the friction free, biased and limited rotational movement of the said shaft, and means for rotating the biased shaft and associated flow control means.

12. A device in combination comprising, a valve, a valve casing, a bracket in said casing, flexible reed spring means secured at one end to said bracket, a flexible valve stem, a member connected at one end to the extended portion of the spring means and at the other end to the valve stem; a rotatable shaft associated with said spring means. for flexing the said extended end portion of the spring means to operate the said valve, means including at least two flexible blades secured to supporting means and having the ends thereof disposed for operation with said shaft with at least one of said blades extending from the supporting means at substantially right angles from the positioning of a second blade, the said flexible blades providing for the support of the said shaft to a biased position and also providing for the friction free and limited rotational movement of the said shaft, and condition responsive means for rotating the biased shaft and associated valve means.

13. Temperature responsive actuating mechanism for a rotatable control member biased to one position, said actuating mechanism comprising a magnet element and armature element relatively rotatable With respect to each other, connecting means adapted to extend between one of saidelements and said control member and adapted when said magnet is attracting said armature to cause said rotatable control member to be held in a second position a ainst its bias, and a thermomagnetic element associated with said magnet and armature for shunting the flux of said magnet away from said armature as long as the temperature of said thermomagnetic element is below a critical value, said thermomagnetic element becoming non-magnetic when heated above the critical value to thus permit the magnet to attract the armature.

14. Temperature responsive actuating mechanism for a remotely located, rotatable control member biased to one position, said actuating mechanism comprising a magnet element and armature element rotatable with respect to each other, a relatively long shaft secured to one of said elements and adapted to be secured to said control member, said shaft being adapted when said magnet is attracting said armature to cause said rotatable control member to be held in a second position against its bias, and a thermomagnetic element associated with said magnet and armature for shunting the flux of said magnet away from said armature as long as the temperature of said thermomagnetic element is below a critical value, said thermomagnetic element becoming nonmagnetic when heated above the critical valu to thus permit the magnet to attract the armature.

15. Temperature responsive actuating mechanism for a rotatable control member normally assuming one position, said actuating mechanism comprising a magnetic element and a Curie point element relatively rotatable with respect to each other, a shaft secured to one of said elements and adapted to be secured to said control member, and supporting means for said shaft comprising crossed flexible blades disposed at right angles to each other with the point of crossing collinear with said shaft, said shaft being adapted when the temperature of the Curie point element is above the Curie point to cause said control member to be held in a second position.

16. A valve comprising a valve casing, a valve seat, a valve member movable with respect to said valve seat, a flat resilient member rigidly secured at one end within said casing, a valve member supported by the other end of said member and biased by said member in one direction, and a rotatable shaft rotatable about an axis parallel along a plane intermediate th legs of said substantially U-shaped magnets, one of said magnetic elements being of a thermomagnetic material whose permeability is changed upon being heated, and a shaft mounted for axial rotation about the axis of rotation of said magnetic elements and connecting the movable magnetic member of said actuating mechanism with said rotatable control member.

WALDO H. IQIIEVER.

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