US2601579A

US2601579A - Curie point valve

Info

Publication number: US2601579A
Application number: US28640A
Authority: US
Inventors: Robert A Wittmann
Original assignee: Individual
Current assignee: Individual
Priority date: 1948-05-22
Filing date: 1948-05-22
Publication date: 1952-06-24
Anticipated expiration: 1969-06-24

Description

June 24,1952 R A WITTMANN 2,601,579

CURIE POINT VALVE Filed May 22, 1948 I l f6 j. /6 )50 f5, 2.5' @1 \L\ m Patented June 24, 1952 UNITED STATES PATENT OFFI CURIE POINT VALVE Robert A. Wittmann, Chicago, Ill.

Application May 22, 1948, Serial No. 28,640

6 Claims. 1

My invention relates, generally, to valves and it has particular relation to valves that are controlled in response to predetermined temperature change.

Among the objects of my invention are: To employ a stationarily mounted magnet, such as a permanent magnet, and Curie point metal for controlling the movement of a valve member to open or close a valve depending upon whether the metal is abovev or below its Curie point; to bias the valve member to close one of the valve ports; to employ gravity as the biasing force; to position the Curie point metal underneath the permanent magnet `where it shunts the flux thereof when it is below the Curie point and permits the magnet to attract the valve member when it is above the Curie point; to position the permanent magnet, Curie point metal and valve member in a housing of non-magnetic material having a high thermal conductivity; to locate one port in the upper part of the housing and another port in the lower part of the housing with a communication therebetween through the permanent magnet and Curie point metal; to employ a spherical member of magnetic material for the valve member; to employ this construction in a three way valve; and to join the upper and lower portions of the housing together by an annulus of Curie point metal.

Other objects of my invention will, in part, be obvious and in part appear hereinafter.

My invention is disclosed in the embodiments thereof shown in the accompanying drawing and it comprises the combination of elements and arrangement of parts which will be exemplified in the constructions hereinafter set forth and the scope of the application of which will be indicated in the appended claims.

For a more complete understanding of the nature'and scope of my invention reference can be had to the following detailed description, taken together with the accompanying drawing, in which:

Figure 1 is a view partly in elevation and partly in section taken along the line I-I of Figure 2 and showing one embodiment of my invention;

Figure 2 is a view, in side elevation, of a valve in which my invention is embodied;

Figure 3 is a view, similar to Figure 1, but showing the valve in the open position;

Figure 4 shows a three way valve embodying the present invention, the valve member being shown in the unattracted position;

Figure 5 is a view, similar to Figure 4, but

2 showing the valve member in the attracted position; and v Figure 6 is a vertical cross-sectional view of a further modification of my invention in which a portion of the valve housing is formed by an annulus of Curie point metal which is also employed for shunting the flux of the permanent magnet under certain operating conditions.

Referring now particularly to Figures 1, 2 and 3 of the drawing. it will be observed that the reference character I0 designates, generally, a valve of the two way type which may be employed in the ignition systems disclosed in my copending applications Serial Nos. 722,584 and 767,707, filed, respectively, January 17, 1947, and August 9, 1947. Other applications of the valve I0 will be apparent to those skilled in the art, reference being had to these copending applications for illustrative. purposes only.

The valve I0 includes a valve housing which is indicated, generally, at II and is formed of non-magnetic material such as brass, stainless steel, etc. In some applications the valve housing may be formed of Curie point metal. The valve housing II is circular in cross-section and has an upper valve housing portion I2 which is larger in diameter than a lower valve housing portion I3, these portions being interconnected by an intermediate portion I4 which provides a step or shoulder the function of which will be apparent presently. The upper end of the valve housing Il may be closed by a cover I5 which may be secured in place by suitable screws I6. At the lower end of the lower valve housing portion I3 a cover II may be secured by suitable means.

A port I8 is provided in the lower cover I'I and, for illustrative purposes, the port I8 can be considered an exhaust or outlet port. The port I8 has a conical valve seat I9 which is arranged to be engaged by a valve member 20 in the form of a sphere normally of magnetic material. For a purpose to be explained hereinafter the valve member 20 may be formed of Curie point metal. When the valve member 20 engages the spherical valve seat I9. the exhaust port I8 is closed or sealed against the flow therethrough of iluid, such as gas, which may be used for heating or cooking purposes or for creating pressure on a diaphragm, or for other purposes. A valve port 2| may be provided in the upper valve housing portion I2. Since the valve port I8 is considered to be an exhaust port, theV valve port 2| can be considered to be an inlet or intake port. However. it will be understood that the functions of the ports I8 and 2| can be reversed.

Immediately above the valve member 2U and resting on the shoulder which is provided by the intermediate portion I4 of the valve housing II is a body 24 of Curie point metal which is annular in shape and serves to support a stationary magnet which may be a permanent magnet or an electromagnet. Magnet 25 of Figures 1, 2 and 3 is a permanent magnet of an inverted U- shape having pole extensions 2S and 21 which constitute the magnet arms. The space 28 between the

pole extensions

26 and 21 serves to` provide part of the communicating passageway between the intake port 2| and the exhaust port I8. In the body 24 of Curie point metal there is a central opening 29 which has an out-flared portion 30 which is directed toward the valve member 20. A pin 3l of non-magnetic material such as brass or stainless steel extends through the permanent magnet 25 and into the opening 25 and serves to limit the upward movement of the valve member 20 when it is attracted by the permanent magnet 25 under certain operating conditions to be described presently. When the valve member 201 is in the attracted position as shown in Figure 3 the inlet port 2l is placed in communication with the exhaust port I8 through the transverse passageway 28 in the permanent magnet 25 and the opening 29 in the body 24 of Curie point metal. In the attracted position the valve member 20 is moved away from the valve seat I9 to open the normally closed exhaust` port I8.

It is Well known that Curie point metal has the property of changing from a magnetic to a non-magnetic material depending upon its temperture with respect to its Curie point. When the body 24 of Curie point metal is heated to a temperature above its Curie point, it is nonmagnetic. When the body of Curie point metal is at a temperature below its Curie point, it has magnetic properties and, since it is positioned above the valve member 20 and below the permanent magnet 25,- it shunts the magnetic flux `of the latter and prevents the valve member 20 from being attracted upwardly against the normal biasing force of gravity which urges the valve member 2U into sealing engagement with the valve seat I9 to close the exhaust port I8. However, when the body 24 of Curie point metal is heated above its Curie point, it loses its magnetic characteristics Aor permeability and the flux of the magnet 25 no longer is shunted thereby. The design of the parts making up the valve IIl is such that under these conditions, the permanent magnet 25 is capable of attracting the valve member 20 and overcoming the biasing force of gravity urging the same downwardly. Accordingly, when the valve member 20 is attracted by the permanent magnet 25 to the position shown in Figure 3, the valve I is opened. v

By way of illustration` it is pointed out that the valve III may be employed in conjunction with a pilot jet. 32 of a gas burning device such as a kitchen range, gas furnace or the like. The flame 33 from the pilot jet 32 impinges on the valve housing II which, as indicated, is formed of a material having a relatively high heat conductivity. The heat from lthe flame 33 is transmitted to the body 24 of Curie point metal land it `is suil'cient to heat the same above its Curie pol-nt and maintain it -in this operating condition. Therefore, as long as the flame 33 continues to impinge against the Valve housing II,

the body 24 is maintained above its Curie point and the permanent magnet 25 holds the valve member 20 in the attracted position shown in Figure 3, thereby maintaining the valve I0 in the open position.

When the flame 33 is extinguished, as illustrated in Figure 1, the body 24 cools below its Curie point, becomes magnetic and shunts the flux from the permanent magnet 25. The biasing force of gravity then is suicient to overcome what residual magnetic attraction there may be for holding th-e valve member 2U in the upper position and, as a result, the valve member 20 dro-ps to the position shown in Figure 1, thereby closing the valve I.

Immediately after the flame 33 is extinguished the Curie point body member 24 will still be above its Curie point so that the valve 28 will remain in its attracted position, as shown in Figure 3. Consequently, gas will continue to flow through the valve I0 and the flow of gas will serve to hasten the cooling of the Curie point body 24 since it is directly in the path of the flowing gas. As a result. the temperature of the body 24 will quickly drop below its Curie point and the valve will promptly close by reason of the body 24 regaining its permeability and shunting the flux of magnet 25, whereupon the valve member 20 drops on to its valve seat I9.

While a flame 33 has been illustrated as being employed for changing the temperature of the body 24 of Curie point metal, it will be understood that other sources of heat, such as electrical heating devices, may be employed for controlling the functioning of the valve I0. Accordingly, lit will be understood that the flame 33 is shown for illustrative purposes only and is not to be co'nsidered as being the only source of heat that can be employed for controlling the functioning of the valve I0.

For the purpose of providing a safety featur in the Valve I0 it is contemplated that the valve member 2D itself be constructed of Curie point metal, but having a higher Curie point than the body member 24. In the event that the valve should become overheated due to a defect in associated appliances, the valve member 20 would eventually become heated above its Curie point, and drop away from the magnet 25 'and on to its seat I9, whereby the valve would be closed. However, in normal operation, the temperature of the valve member 28 would be well below its Curie point.

The valve IIJ shown in Figures 1, 2 and 3 land described hereinbefore is of the two way type, i. e. it has two ports I8 vand 2I. If desired another port can be provided thus making it a three way Valve.

In Figures 4 and 5 of the drawing there is' i1- lustrated a valve I0' which is of the three way type. That is, 'in addition to having the valve ports I8 `and 2I, previously described, it also may have a third port 36. The valve member 20 is arranged as before to control theopening or closing of the port I8. When the valve member l2'I'l occupies the position shown in Figure 4 of the drawing, the ports 2I and 36 are placed in communication through an out-flared opening 30 in the body 24 of Curie point metal and a transverse passageway 28 between the pole extensions 2E Vand 2'I of the permanent magnet 25'. Now, when the ame 33 heats thebody 24 above its vCurie point, the valve and the 'v alve member 20 is moved upwardly to `close off the out-flared passageway V'38' in the body 24", as il- -lustrated in Figure 5, thereby cutting oi communication with the valve port 2| and placing the valve ports I8 and 36 in communication. It will be observed that the valve housing |I for the valve I shown in Figures 4 and 5 of the I drawing is essentially the sameas the valvehous- .housing I I and serves to interconnect the' upper and lower valve housing portions |I2 and 3. The valve I |0 shown in Figure 6 is of the two way type, communication between the parts IIB and I2| being provided through a transverse passageway |28 in the permanent magnet |25. A pin "|3I of non-magnetic material such as brass -or stainless steel extends centrally through the permanent magnet |25 and it has a head |39 at its lower end the under surface |40 of which head is concave for receiving the valve member |20 when it is attracted upwardly by the permanent magnet |25 when the body |24 of Curie point metal is heated above its Curie point in the manner described hereinbefore.

It will be observed that the lower portion II3 of the valve housing is of a smaller diameter than that shown in the valve housings I and Il of Figures 1 and 4, respectively. The lower portion ||3 thereby serves as a guide for the vertically moving valve member |20, while yet providing clearance between itself and said valve member for uid flow. By having the valve seat |I9 conical and downwardly inclined and of suflicient radial extent, it will be seen that even when the valve member |20 descends along the inner side wall of lower portion II3 of valve housing it will be directed to a central position on the valve seat ||9 to close the port I|8. It will readily be observed that if the conical valve seat extends radially to a position wherein its periphery is at a distance from the inner side wall of lower portion II3 of valve housing less than the radius of the valve member |20, then the valve member will always be directed to a central position on the valve seat |I9. As an alternative, the bottom wall |I1 of housing may be downwardly inclined toward port I8 over the whole inner surface of said wall.

Since certain further changes can be made in the foregoing constructions and different embodiments of the invention can be made without departing from the spirit and scope thereof, it is intended that all matter shown in the accompanying drawing and described hereinbefore shall be interpreted as illustrative and not in a limiting sense.

I claim as my invention:

1. In a valve, in combination, a valve housing of non-magnetic material adapted to be located in an upright position and having intake and exhaust ports one of which is located in the bottom of said housing and the other is located in the upper part thereof, a valve member of magnetic material gravity biased to close said one port, a permanent magnet of inverted U-shape in said upper part of said housing for attracting said valve member to move the same upwardly and open the valve by placing said ports in communication through the passageway between the downwardly extending poles of said permanent magnet, and a ring of Curie point metal underneath said permanent magnet for shunting its flux when said metal is below its Curie point whereby said valve member is not attracted and the valve lremains closed, the opening in .said ring `registering with said passageway. f

2. In a valve, in combination, a valve housing of non-magnetic material adapted to be located in an upright position and havingl intake and exhaust ports one of which is located in'the'bottom of said housing and the. other of which is located inthe upper part thereof, a freely movable spherical valve member of magnetic material gravity biased to close said one port, a permarient magnet of inverted U-shape in said upper part of said housing for attracting said Valve member to move the same upwardly and open the valve by placing said ports in communication through the passageway between the downwardly extending poles of'said permanent magnet, non-magnetic stop means against which said valve member is attracted by said permanent magnet and positioned so as not to prevent the now of fluid from the intake port to the exhaust port, and a ring of Curie point metal underneath said permanent magnet for shunting its flux when said metal is below its Curie point whereby said valve member is not attracted and the valve remains closed, the opening in said ring registering with said passageway.

3. In a valve, in combination, a valve housing, a wall of Curie point metal dividing the housing into upper and lower portions and dening a passageway and a valve seat between said portions, a rlrst port and a second port located in the lower portion of the housing and a third port being located in the upper portion of the housing, a valve member of magnetic material for closing said first port, the second port and third port being in communication with said passageway when the valve member closes the rst port, a magnet in the upper portion of the housing, said wall of Curie point metal being adapted to shunt the magnetic flux of said magnet when said metal is below its Curie point, thereby rendering the magnet ineffective to actuate the valve member, and also being adapted to be heated above its Curie point whereby it loses its permeability and permits the magnet to attract the valve member to the valve seat to close off the passageway in the dividing wall and thereby provides communication between the first port and the second port, said dividing wall being disposed in the path of iiuid flow and to the cooling effect thereof.

4. In a valve, in combination, a valve housing of non-magnetic material adapted to be located in an upright position and having intake and exhaust ports one of which is located in the bottom of said housing, a spherical valve member of magnetic material gravity biased to close said one port, a permanent magnet in an upper part of said housing for attracting said valve member to move the same upwardly and open the valve, and a body of Curie point metal underneath said permanent magnet for shunting its fluxi when said metal is below its Curie point whereby said valve member is not attracted and the valve remains closed, said other port being located in the upper part of the housing and communicating with said one port through a passageway extending through the permanent magnet and the body of Curie point metal.

5. The invention, as set forth in claim 4, wherein a third port is located in the lower part of the housing and the valve member in the attracted position closes the passageway to said other port and places said third port in communication with said one port. said thitdvport being in communication with said other port when said one port is closed by said valve member.

6. In a valve, in combination, a valve housing adapted to be located in anl upright position and having intake and exhaust ports one of which is located in the lower part o! said housing, a valve member of magnetic material gravity biased to close said one port. amagnet in saidl upper part o! said housing for' attracting said valve member to move the same upwardly and open the valve and a` body of Curie point metal underneath said magnet for shunting its ux when said metal is below its Curie point, whereby said valve member is not attracted and the valve remains` closed. said body of Curie point metal being in theforxn of an annulus and constituting a, partv of the housing` and joining the upper and lower portions thereof.

ROBERT A. WIT'IMANN.

REFERENCES cuan The' following references are of record in the le of this' patent:V l

UNITED STATES PATENTS '110,167' France July 9, 1934