US2589574A - Electromagnetic valve - Google Patents

Description

March 18, 1952' w, R, I 2,589,574

ELECTROMAGNETIC VALVE .Filed May 22, 1946 l-illllr 1-: 4,0,4 WIIIIIIIIIIIIIIIIIIIAMflI/IIIIM '11,;

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ATTORNEY.

Patented Mar. 18, 1952 ELECTROMAGNETIC VALVE William A. Ray, Glendale, Calif., assignor to General Controls 00., Glendale, Calif., a corporation of California Application May 22, 1946, Serial No. 671,583

This invention relates to electromagnetically operated mechanisms, and particularly to those capable of responding to small electric currents. Such mechanisms are especially useful in gas burner control systems in which the controlling current is obtained by thermoelectricity or photoelectricity.

In an application filed in the name of William A. Bay on September 4, 1944, under Serial Number 552,647, now Patent No. 2,550,297, and entitled Electromagnetically Operated Valve," a device is shown and described wherein the polar area of the operating magnet is made large and the magnetic path is carefully designed to ensure that the reluctance thereof is low, whereby the device is capable of operation by a very small current.

It is an object of this invention to provide a device of improved construction incorporating these features.

It is another object of this invention to provide a reliable device which requires an electric current of small magnitude only for consistent operation, such, for example, as may be provided by a thermoelectric generator, or an electron multiplier tube.

It is another object of this invention to provide a novel electromagnet structure.

It is another object of this invention to provide an electromagnetically operated three-way valve of improved construction.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of one embodiment of the invention. For this purpose there is shown a form in the drawings accompanying and forming part of the present specification. The form will now be described in detail, illustrating the general principles of the invention; but it is to be understood that this detailed description is not to be taken in a limiting sense, since the scope of this invention is best defined by the appended claims.

In the drawings:

Figure 1 is an axial section through a valve incorporating the invention;

Fig. 1-a is a fragmentary section, similar to Fig. 1, on an enlarged scale;

Figs. 2 and 3 are cross sections, taken as indicated by correspondingly numbered lines on Fi 1;

Figs. 4 and 5 are transverse sections, taken as indicated by correspondingly numbered lines on Fig. 2;

Fig. 6 is a cross section, taken as indicated by line 6-6 on Fig. l.

7 Claims. (Cl. 137-139) Referring to the drawings, a valve is shown by way of example, incorporating the features of the invention. The valve comprises a body 3 with a port 4 opening into the upper face of the body, and arranged to be controlled by a closure member 8. For this purpose, the port 4 is formed by an upwardly facing valve seat'5 adapted to be engaged by the closure 8 to close the port. For reasons which will appear hereinafter, the port 4 is located unsymmetrically of the body 3 and the closure 8. Accordingly, projections 6 and I are provided in the body 3 for supplementarily supporting the closure 8 when on the valve seat 5.

An electro-magnet structure 9 is provided for operating the closure 8 to open and to close the port 4. For this purpose, the closure member 8 must be of magnetic material. When the magnet structure 9 is energized the closure member 8 is raised from seat 5 opening port 4; upon deenergization, the member 8 is released and returns to its seat, closing the port. The magnet structure 9 will now be described.

As pointed out in the above mentioned application, the ampere turns required by an electromagnet to produce a definite intensity of magnetization depend mainly on the magnetic density and the reluctance of the magnetic path,

- while the pull exerted by the magnet is a function of the polar area as well as of the magnetic density. Thus by increasing the polar area, the pull of the magnet may be increased, and by arranging that the reluctance be low, the pull may be further increased, without an increase in the number of ampere turns. The reluctance may be reduced by eliminating as many joints in the magnet circuit as is possible, ensuring that in such joints as exist the surfaces are sufficiently large and in intimate contact and by providing the smallest possible air gap. Additionally, the magnet core should be of small diameter, so that the mean length of a turn of the magnet winding, and hence the total wire required, is reduced.

Referring to Fig. l, the magnet 9 comprises a cylindrical core ID of relatively small diameter, with an enlarged pole piece H at its lower end providing a large polar area I2 for attracting the closure member 8. The upper end of the core III is provided with a large circular head l3 having a tapered exterior surface l4 and a threaded extension [5. The pole piece H and the-head l3 both are integral with the core [0. An energizing coil I 6 is wound on the core l0 and is adapted to be connected through leads Iii-a and It-b with a source of electric energy, such as a thermoelectric generator or an electron multiplier tube (not shown).

An inverted cup or shell H, which may be formed of sheet metal having good magnetic qualities, is secured on core II] in a manner to provide ajoint of low reluctance. For this purpose the top of the shell I1 is provided with .a reduced tapered opening I8, closed by a cap IB-a secured as by welding to the shell I1, and forming a recess I9 for accommodating the head I3.

A nut 20 threaded on the extension I serves, by engagement with the cap IB-a, to urge head I3 tightly into engagement with the wall of the recess I9.

The lower end portion of the shell I! forms an annular polar surface extending about the pole piece II and cooperating therewith to attract the magnetic closure member 8. The area of this polar surface may be increased so as to be substantially as large as the polar area I2, by providing an inturned edge or flange 2I on the lower end of shell I]. The partaare so proportioned that, when the shell I! is secured tightly in the core I0, the lower surface 22 .of flange 2| lies in the plane of the polar surface I2. The closure member 8, in released position on seat is positioned quite closely to the magnet faces I2 and 22, for example from to away, so that upon energization of the winding I3, the member 8 is attracted toward these faces. As is well understood, the core I0 and shell I'I,-as well as the closure 8, are formed of material which does not remain magnetized after deenergization of the winding IE. Hence upon deenergization of the coil I6, the closure 8 is released substantially. immediately to return to seat 5 by gravity.

The shell IT has anexterior extension 24 at its lower end secured to the shell as by welding, and providing an outwardly directed annular flange 25 by which the shell is secured in fluidtight relation to a flange 3-a on the body 3. In this way the shell I! forms a fluid-tight chamber into which the port 4 opens.

Referring. in detail. to the structure of Fig. l, a three way valve is shown. Thus one or more ports 28 are provided, which are arranged to be closed by the closure 8 when port 4' is uncovcred, and vice versa. These ports 28 are formed inthe pole piece I I by openings through the polar face I2, into an annular chamber 29 formed in the pole piece. Each port 28 is provided with a short tube or nozzle 38 which extends by a small distance, such as .005", beyond the pole face I2 to provide a seat for cooperating with the closure member 8. A single nozzle 30 and pins for supporting the closure member 8 may be provided in the pole piece I I, in a manner similar to seat 5 and pins 6 and I, or, as shown, three nozzles 30 may be provided, as desired. The seats pro vided by these nozzles 30 lie in a common plane closely'spaced to the pole face I2'as above pointed out, so that, when the closure 8 is attracted by the magnets, the closure 8 will seat accurately on the nozzles 30 and effectively close allthe ports; 28; At the same time only a very small air; gap: remains between the closure 8 and the magnet faces I2 and 22. This ensures against sticking. of the armature or closure 8' after the magnet-is deenergized.

Theinterior of the shell I! is in free communicationwith a pressure space 3i or the like, dcfinedi'n part by a wall, afragmentof which is shown-at 32, by a passage33v extending vertically through the body The'portor: portson. one

side of the closure 8 then serve to admit fluid pressure to the chamber 3|, while the port or ports on the opposite side serve to release such pressure.

In the present instance, ports 28 serve to admit fluid. For this purpose, a port 34 coaxial with the core It] and closure 8 is providedin the body, and is adapted to be connected with a suitable source by a conduit (not shown) and the passage 35. A shallow bore 36 is formed in pole piece II (see Fig. 1-11) aligned with the port 34 and is connected with annular chamber 29 by one or more radial ports 3?. A short tubular member 38 of non-magnetic material passing through a clearance aperture 39 in the closure 8, serves to connect the bore 38 with the port 34.

To facilitate the assembly of the magnet structure 9 on the body 3, the tube 38 with the closure 8 in place thereon is fixed in the bore 36 of pole piece II. The tube 38 is freely slid-able in port 34 so asto be readily inserted therein when the magnet structure is mounted on the body 3. To prevent leakage about thetube 3.8, port 34 has a counter bore fi l-a, for accommodating a resilient packing ring 46,. which is compressed into sealing relation by a shoulder 4| on the .tube 38 (see Fig. l-a) when the parts are assembled.

The port 4 serves to permit discharge of fluid from the pressure space and, for this purpose, is connected with a threaded opening 42 inthe body 3, by a passage 48. Valve means 44 may be provided for controlling the rate of discharge.

To ensure return of the closure 8 to its initial position when the electro-magnet 9' is deenergized, a plurality of upwardly flexed light leaf springs 35 are provided in recesses 4t onthe upper side of the closure 8 angularly spaced about its edge. These springs continuously engagethe flange 2 I, urging the closure downwardly. When the magnet 9 is energized, the closure ,8 moves upwardly against the face of the springs 45, the springs being flattened into the respective recesses 46.

One element of a conventional connector-may be provided at 4? in the shell Ilto facilitate connection of the leads IE-a and Iii-b to the cable or conductor leading to the thermocouple or other source of electric current. 7

When the coil i6 is deenergized, closure 8 closes port 4. Fluid from inlet .35 then can pass through ports 34 and 28 and the space in shell I1,- into the outlet 33, but not to outlet 42. When closure 8 is lifted upon energizing coil .9, fluid from inlet 35. can pass, as before, to the shell IT, and out through port 4 to outlet 42,. but flow to outlet 33 is interrupted by closure of port 28.

The inventor claims:

1. In an electromagnetic valve: a valve body providing a support; an electromagnet having a core mounted on said body with one pole face of said core spaced above said support; means forming a port in said core opening through said face, spaced from the axis of the core and surrounded by a valve seat; a. magnetic. closure member interposed. between said support and said seat for movement toward and awayrroin said seat to control said. port in accordance with the energization and deenergization of said magnet; and means forming a'passage connected with said port, including a tubular member extending axially of said core to said body and.- passing through said closure;

2. In an electromagnetic valve: a valve body having a port surrounded by a seat; means mounted on said body and definingtlrerewitrta closed space, said means including an electromagnet having a core with one pole face spaced above and facing said seat, there being a port in said core opening through said face and surrounded by a seat facing oppositely with respect to the seat in the body; a magnetic closure member movable between said seats in accordance with energization or deenergization of said magnet to control said ports; means forming a passage communicating with the port in the core, including a hollow member extending between the body and the core, and passing through an opening in the closure member; there being a passage connected with said space.

3. In an electromagnetic valve: a valve body providing a port surrounded by a seat: means mounted on said body and defining therewith a closed space, said means including an electromagnet secured on said body having a core with one pole face spaced above and facing said seat, there being a port in said core opening through said face and surrounded by a seat facing oppositely with respect to the seat in the body, the axis of the core being offset laterally from the ports; a magnetic closure member movable between said seats in accordance with energization or deenergization of said magnet, to control said ports; means forming a passage communicating with the port in the core including a tubular element extending axially of the core between the body and the core, and freely accommodated in an axial opening through the closure member; there being a passage connected with said space.

4. In an electromagnetic valve: a valve body providing a port surrounded by a seat; means mounted on said body and defining therewith a closed space, said means including an electromagnet'secured on said body having a core with one pole face spaced above and facing said seat, there being a port in said core opening through said face and surrounded by a seat facing oppositely with respect to the seat in the body, the axis of the core being ofiset laterally from the ports; a magnetic closure member movable between said seats in accordance with energization or deenergization of said magnet, to control said ports; means forming a passage communicating with the port in the core including a tubular element projecting axially from the core and secured thereto, there being an opening in said body for slidingly accommodating said element, means sealing between said element and the body; and means forming a passage communicating with said space.

5. In an electromagnetic valve: an electromagnet having a core provided with a pole face; means forming a port in said core opening through said face and surrounded by a valve seat; a magnetic closure member movable toward and away from said seat to control said port in accordance with the energization and deenergization of said magnet; and means passing through said closure and extending into said core to form a passage connected with said port.

6. In an electromagnetic valve: a valve body having a port surrounded by a seat; an electromagnet having a core with one pole face spaced from said seat, there being a port in said core opening through said face and surrounded by a seat facing oppositely with respect to the body seat; a magnetic closure member movable between said seats in accordance with energization or de-energization of said magnet to control said ports; and means extending into said core and passing through said closure member to form a passage communicating with the port in the core.

7. In an electromagnetic valve: a valve body having a port surrounded by a seat; an electromagnet having a core with one pole face spaced from said seat, there being a port in said core opening through said face and surrounded by a seat facing oppositely with respect to the body seat; a magnetic closure member movable between said seats in accordance with energization or de-energization of said magnet to control said ports; means extending into said core and passing through said closure member to form a passage communicating with the port in the core; and means in said body for controlling the flow of fluid through said body port.

WILLIAM A. RAY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 722,302 Holley et a1 Mar. 10, 1903 1,150,562 Vose Aug. 17, 1915 1,754,740 Clarkson Apr. 15, 1930 2,087,387 Price July 20, 1937 2,096,763 Ray Oct. 26, 1937 2,261,562 Ray Nov. 4, 1941 2,289,456 Ray July 14, 1942 2,324,642 Peterson July 20, 1943 2,353,848 Ray July 18,1944 2,358,828 Ray Sept. 26, 1944 2,370,752 Ray Mar. 6, 1945 2,372,853 Ray Apr. 3, 1945 2,374,895 Ray May 1, 1945 2,435,076 Hall Jan. 27, 1948 2,461,772 Ray Feb. 15, 1949 2,465,036 Ray Mar. 22, 1949 FOREIGN PATENTS Number Country Date 16,513 Great Britain 1907 574,387

France July 10, 1924

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