US2548239A - Core structure for electromagnets - Google Patents

Core structure for electromagnets Download PDF

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Publication number
US2548239A
US2548239A US745951A US74595147A US2548239A US 2548239 A US2548239 A US 2548239A US 745951 A US745951 A US 745951A US 74595147 A US74595147 A US 74595147A US 2548239 A US2548239 A US 2548239A
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Prior art keywords
shell
head
core structure
core member
end wall
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Expired - Lifetime
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US745951A
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William A Ray
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General Controls Co
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General Controls Co
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Priority to US745951A priority Critical patent/US2548239A/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/06—Electromagnets; Actuators including electromagnets
    • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
    • H01F7/16—Rectilinearly-movable armatures
    • H01F7/1638—Armatures not entering the winding
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/86493—Multi-way valve unit
    • Y10T137/86718—Dividing into parallel flow paths with recombining
    • Y10T137/86759—Reciprocating
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/87265—Dividing into parallel flow paths with recombining
    • Y10T137/87507—Electrical actuator

Definitions

  • This invention relates to electromagnets, and more particularly to improvements in core structures therefor.
  • An object of the invention is to providein a core structure of the type which comprises a cupshaped shell and a rod-like core member centrally disposed in the shell and extending from the end wall thereof-means for substantially eliminating any airegap at the junction of the core member and the shell; this object being accomplished by providing the core member with an integral head which is so enlarged that it is substantially ceextensive with the end wall of the shell, and whose surface is shaped to conform exactly to the cooperating surface of the shell end-wall.
  • Another object is to provide simple but effective means for securing the core-member head in intimate engagement with the shell end-wall.
  • Another object is to form the core member so that it constitutes a bobbin for the energizing coil.
  • Figure l is a sectional view of an electromagnetically operated fluid control valve embodying this invention.
  • Figure 2 is a plan of the valve casing shown in Fig. l, with the armature-closure 20 removed.
  • I I is a valve casing having an inlet I2 and an outlet I 3 separated by a partition I 4 having in its horizontal portion three concentrically-arranged ports I5; the material of the partition being raised around each of the ports to form valve seats I8.
  • Communication between the inlet I2 and the chamber I 1 above the partition is afforded by a vertical opening I8 which leads to a generally-semicircular trough l9 below the chamher and extending around a major portion of the upper part of the partition to permit more uniform distribution of fluid to the several ports.
  • Normally resting on the seats I6 is a disk-like closure 20.
  • the closure is of magnetic material so that it also serves as an armature attractable by an electromagnet mounted on the top of the valve I casing.
  • This electromagnet comprises a generally-cylindrical cup-shaped shell 2I, formed of magnetic sheet material, which is secured by its flanged bottom portion 22 to the raised sidewall 23 of the valve casing; a thin diaphragm 24,
  • an elongated round core-member 25 Centrally disposed within the shell 2
  • the top surface of the head 23 is preferably formed as a segment of a sphere of large radius to ensure uniform engagement of their cooperating surfaces when the shell endwall is stretched over the head by the rolling operation, so that the possibility of there being an air-gap between these surfaces is substantially eliminated.
  • the core member 25 At the bottom or" the core member 25, and preferably integral therewith, is a disk-like pole piece 29 whose undersurface or pole-face is in the plane of the mouth of the shell; the diameter of the rim of the pole piece being sufficientlysmaller than the inner diameter of the shell that a suitable working-gap for the electromagnet is formed adjacent the mouth of the shell.
  • the head 26 and pole piece 29 constitute the core member a bobbin on which an energizing coil 30 is wound, with insulating material 3I therebetween.
  • the leads 32 of the coil are connected to terminal posts 33 insulatingly mounted in openings through a protruded side-portion 34 of the shell; a strap 35, of insulating material and having square openings cooperating with squared portions of the posts, being provided to prevent rotation of the posts when connections with an external circuit for the electromagnet are made or removed.
  • the coil leads are soldered to the terminal posts which are then mounted in place, the leads being relatively long for this purpose.
  • the shell is then placed in a fixture and, with the core member held firmly in position, the side wall of the shell is rolled tightly around the rim of the core-member head so that the end wall of the shell is stretched into intimate engagement with the top surface of the head. If necessary, the pole faces of the shell and the core member are brought into accurate alignment by grinding.
  • the armature-closure 20 is normally held in sealing engagement with the valve seats I6 by the force of a bias spring 36 compressed between the armature and the pole piece 29.
  • the electromagnet When the electromagnet is energized by passage of current through its coil, the armature-closure is attracted into engagement with the pole faces of the electromagnet so that the valve ports are uncovered.
  • a core structure for an electromagnet, eom prising a cup-shaped shell of magnetic sheet material having side walls and an end wall integral therewith; an elongated core member centrally disposed within said shell and in such spaced relation to said side walls of the shell as to define therewith a space for an energizing coil; said core member having an integral enlargement at its inner end forming a relatively thin head substantially coextensive with, and shaped to conform to, the inner surface of said end wall of the shell; and means for securing I said head in intimate engagement with said surface.
  • a core structure as defined in claim 1, and wherein said means for securing said head to said end wall of the shell comprises a reentrant portion of the side wall of the shell in engagement with the rim of the head.
  • a core structure for an electromagnet comprising: a generally-cylindrical cup-shaped shell of magnetic sheet material having a side wall and an end wall integral therewith; an elongated round core member centrally disposed within said shell and of such diameter as to define with said side wall of the shell a relatively-large annular space for an energizing coil; said core member having an integral enlargement at its inner end forming a disk-like head whose diameter is substantially equal to the inner diameter of the shell, the outer surface of said head being shaped to conform to the inner surface of said end wall of the shell; and means for securing said head in intimate engagement with said end wall.
  • said means for securing said head to said end wall of the shell comprises a reentrant portion of the side wall of the shell in engagement with the rim of the head.
  • a core structure for an electromagnet comprising: a generally-cylindrical cup-shaped shell of magnetic sheet material having a side wall and an end wall integral therewith; an elongated round core member centrally disposed within said shell and of such diameter as to define with said side wall of the shell a relatively-large annular space for an energizing coil; said core member having an integral enlargement at its inner end forming a disk-like head whose diameter is substantially equal to the inner diameter of the shell, the outer surface of said head being shaped to conform to the inner surface of said end wall of the shell; and means for securing said head in intimate engagement with said end wall; the other end of said core member being enlarged to provide a disk-like pole piece whose face is in the plane of the mouth of the shell, said head and said pole piece constituting the core member a bobbin for said coil.
  • a core structure as defined in claim 7, and wherein said means for securing said head to said end wall of the shell comprises a reentrant portion of the side wall of the shell in engagement with the rim of the head.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Magnetically Actuated Valves (AREA)

Description

April 10, 1951 w. A. RAY 2,548,239
CORE STRUCTURE FOR ELECTROMAGNETS NNNNN TOR, h/ILL/AMA. Q4 Y TTTTTTT Y Patented Apr. 10, 1951 CORE STRUCTURE FOR ELECTROMAGNETS William A. Bay, North Hollywood, Calif., assignor to General Controls (30., Glendale, Calif., a corporation of California Application May 5, 1947, Serial No. 745,951
9 Claims.
This invention relates to electromagnets, and more particularly to improvements in core structures therefor.
An object of the invention is to providein a core structure of the type which comprises a cupshaped shell and a rod-like core member centrally disposed in the shell and extending from the end wall thereof-means for substantially eliminating any airegap at the junction of the core member and the shell; this object being accomplished by providing the core member with an integral head which is so enlarged that it is substantially ceextensive with the end wall of the shell, and whose surface is shaped to conform exactly to the cooperating surface of the shell end-wall.
Another object is to provide simple but effective means for securing the core-member head in intimate engagement with the shell end-wall.
Another object is to form the core member so that it constitutes a bobbin for the energizing coil.
For full understanding of the invention, and further appreciation of its features and advantages, reference is to be had to the following detailed description and accompanying drawing, and to the appended claims.
In the drawing:
Figure l is a sectional view of an electromagnetically operated fluid control valve embodying this invention; and
Figure 2 is a plan of the valve casing shown in Fig. l, with the armature-closure 20 removed.
Indicated in the drawing by the numeral I I is a valve casing having an inlet I2 and an outlet I 3 separated by a partition I 4 having in its horizontal portion three concentrically-arranged ports I5; the material of the partition being raised around each of the ports to form valve seats I8. Communication between the inlet I2 and the chamber I 1 above the partition is afforded by a vertical opening I8 which leads to a generally-semicircular trough l9 below the chamher and extending around a major portion of the upper part of the partition to permit more uniform distribution of fluid to the several ports. Normally resting on the seats I6 is a disk-like closure 20.
The closure is of magnetic material so that it also serves as an armature attractable by an electromagnet mounted on the top of the valve I casing. This electromagnet comprises a generally-cylindrical cup-shaped shell 2I, formed of magnetic sheet material, which is secured by its flanged bottom portion 22 to the raised sidewall 23 of the valve casing; a thin diaphragm 24,
of material such as 0.005-inch-thick copper, being interposed between these parts to shield the interior of the shell from the fluid in the valve casing, as well as to serve as a non-magnetic separator for the armature.
Centrally disposed within the shell 2| is an elongated round core-member 25 having at its inner or top end an integrally-formed disk-like head 26 around whose rim the material of the side wall of the shell is deformed or rolled, as indicated at 21, to secure the head in intimate engagement with the inner surface of the end wall 28 of the shell. The top surface of the head 23 is preferably formed as a segment of a sphere of large radius to ensure uniform engagement of their cooperating surfaces when the shell endwall is stretched over the head by the rolling operation, so that the possibility of there being an air-gap between these surfaces is substantially eliminated.
At the bottom or" the core member 25, and preferably integral therewith, is a disk-like pole piece 29 whose undersurface or pole-face is in the plane of the mouth of the shell; the diameter of the rim of the pole piece being sufficientlysmaller than the inner diameter of the shell that a suitable working-gap for the electromagnet is formed adjacent the mouth of the shell. The head 26 and pole piece 29 constitute the core member a bobbin on which an energizing coil 30 is wound, with insulating material 3I therebetween. The leads 32 of the coil are connected to terminal posts 33 insulatingly mounted in openings through a protruded side-portion 34 of the shell; a strap 35, of insulating material and having square openings cooperating with squared portions of the posts, being provided to prevent rotation of the posts when connections with an external circuit for the electromagnet are made or removed.
Before assembling the core member and coil in the shell, the coil leads are soldered to the terminal posts which are then mounted in place, the leads being relatively long for this purpose. The shell is then placed in a fixture and, with the core member held firmly in position, the side wall of the shell is rolled tightly around the rim of the core-member head so that the end wall of the shell is stretched into intimate engagement with the top surface of the head. If necessary, the pole faces of the shell and the core member are brought into accurate alignment by grinding.
The armature-closure 20 is normally held in sealing engagement with the valve seats I6 by the force of a bias spring 36 compressed between the armature and the pole piece 29. When the electromagnet is energized by passage of current through its coil, the armature-closure is attracted into engagement with the pole faces of the electromagnet so that the valve ports are uncovered.
The specific embodiment of my invention herein shown and described is susceptible of modification without departing from the spirit of the invention, and I intend therefore to be limited only by the scope of the appended claims.
I claim as my invention:
1. A core structure for an electromagnet, eom prising: a cup-shaped shell of magnetic sheet material having side walls and an end wall integral therewith; an elongated core member centrally disposed within said shell and in such spaced relation to said side walls of the shell as to define therewith a space for an energizing coil; said core member having an integral enlargement at its inner end forming a relatively thin head substantially coextensive with, and shaped to conform to, the inner surface of said end wall of the shell; and means for securing I said head in intimate engagement with said surface.
2. A core structure as defined in claim 1, and wherein said means for securing said head to said end wall of the shell comprises a reentrant portion of the side wall of the shell in engagement with the rim of the head.
3. A core structure as defined in claim 1, and wherein the conforming surfaces of said head and of said end wall of the shell are respectively convex and concave.
4. A core structure for an electromagnet, comprising: a generally-cylindrical cup-shaped shell of magnetic sheet material having a side wall and an end wall integral therewith; an elongated round core member centrally disposed within said shell and of such diameter as to define with said side wall of the shell a relatively-large annular space for an energizing coil; said core member having an integral enlargement at its inner end forming a disk-like head whose diameter is substantially equal to the inner diameter of the shell, the outer surface of said head being shaped to conform to the inner surface of said end wall of the shell; and means for securing said head in intimate engagement with said end wall.
5. A core structure as defined in claim 4, and
wherein said means for securing said head to said end wall of the shell comprises a reentrant portion of the side wall of the shell in engagement with the rim of the head. 7
6. A core structure as defined in claim 4, and wherein said outer surface of said head forms a segment of a sphere of large radius.
7. A core structure for an electromagnet, comprising: a generally-cylindrical cup-shaped shell of magnetic sheet material having a side wall and an end wall integral therewith; an elongated round core member centrally disposed within said shell and of such diameter as to define with said side wall of the shell a relatively-large annular space for an energizing coil; said core member having an integral enlargement at its inner end forming a disk-like head whose diameter is substantially equal to the inner diameter of the shell, the outer surface of said head being shaped to conform to the inner surface of said end wall of the shell; and means for securing said head in intimate engagement with said end wall; the other end of said core member being enlarged to provide a disk-like pole piece whose face is in the plane of the mouth of the shell, said head and said pole piece constituting the core member a bobbin for said coil.
8. A core structure as defined in claim 7, and wherein said means for securing said head to said end wall of the shell comprises a reentrant portion of the side wall of the shell in engagement with the rim of the head.
9. A core structure as defined in claim 7, and wherein said outer surface of said head forms a segment of a sphere of large radius.
WILLIAM A. RAY.
EEFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,654,642 Geissinger Jan. 3, 1928 1,965,053 Powers July 3, 1934 2,155,358 Cyr Apr. 18, 1939 2,353,835 Lane et al. July 18, 1944 2,411,778 De Wilde Nov. 26, 1946 2,422,260 Ray June 17, 1947 2,465,036 Ray Mar. 22, 1949 2,479,398 Parsons Aug. 16, 1949
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Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2675022A (en) * 1949-06-09 1954-04-13 Donald I Bohn Injection valve and actuating means therefor
DE1052569B (en) * 1954-10-14 1959-03-12 Zahnradfabrik Friedrichshafen Electromagnet
US3001757A (en) * 1958-04-09 1961-09-26 Chrysler Corp Magnetic fuel injection nozzle
DE1203881B (en) * 1956-05-07 1965-10-28 Detroit Coil Co Electromagnetic actuation device
US3534310A (en) * 1966-08-29 1970-10-13 Etablis Public A Caractere Ind Electrical connector for use in conductive media
US3729025A (en) * 1970-08-31 1973-04-24 Bendix Corp Solenoid valve with stroke insensitive port
US3960361A (en) * 1975-03-14 1976-06-01 Bertea Corporation Solenoid valve
US4656450A (en) * 1986-05-12 1987-04-07 Northern Telecom Limited Transformer and ferrite core structure therefor
US4714234A (en) * 1982-09-07 1987-12-22 Greatbatch Enterprises, Inc. Low power electromagnetic valve
US4787418A (en) * 1987-09-15 1988-11-29 Colt Industries Inc. Valve assembly and fuel metering apparatus
US4905962A (en) * 1988-09-15 1990-03-06 Kaiser Aerospace & Electronics Corp. Fast-acting electromagnetic solenoid valve
US6273224B1 (en) * 1997-08-12 2001-08-14 Hr Textron, Inc. Shock absorber mounted electromagnetically operated damper valve
US20030020039A1 (en) * 2001-06-28 2003-01-30 Rainer Haeberer Solenoid valve for controlling an injection valve of an internal combustion engine
EP1378693A1 (en) * 2002-07-05 2004-01-07 Danfoss A/S Radiator valve
US20190226588A1 (en) * 2014-06-13 2019-07-25 Horiba Stec, Co., Ltd. High conductance valve for fluids and vapors

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1654642A (en) * 1924-10-27 1928-01-03 Harry G Geissinger Electromagnetic fuel-control valve
US1965053A (en) * 1930-02-10 1934-07-03 Timken Silent Automatic Compan Valve
US2155358A (en) * 1936-01-08 1939-04-18 Honeywell Regulator Co Fluid flow regulator
US2353835A (en) * 1942-04-25 1944-07-18 Aeronautical Mfg Corp Electromagnetic actuating mechanism for solenoid valves or the like
US2411778A (en) * 1942-09-22 1946-11-26 Penn Electric Switch Co Gun firing solenoid
US2422260A (en) * 1942-11-23 1947-06-17 Gen Controls Co Electromagnetic operator
US2465036A (en) * 1943-09-13 1949-03-22 Gen Controls Co Valve structure
US2479398A (en) * 1945-10-27 1949-08-16 John B Parsons Piston and cylinder assembly embodying a solenoid controlled valve

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1654642A (en) * 1924-10-27 1928-01-03 Harry G Geissinger Electromagnetic fuel-control valve
US1965053A (en) * 1930-02-10 1934-07-03 Timken Silent Automatic Compan Valve
US2155358A (en) * 1936-01-08 1939-04-18 Honeywell Regulator Co Fluid flow regulator
US2353835A (en) * 1942-04-25 1944-07-18 Aeronautical Mfg Corp Electromagnetic actuating mechanism for solenoid valves or the like
US2411778A (en) * 1942-09-22 1946-11-26 Penn Electric Switch Co Gun firing solenoid
US2422260A (en) * 1942-11-23 1947-06-17 Gen Controls Co Electromagnetic operator
US2465036A (en) * 1943-09-13 1949-03-22 Gen Controls Co Valve structure
US2479398A (en) * 1945-10-27 1949-08-16 John B Parsons Piston and cylinder assembly embodying a solenoid controlled valve

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2675022A (en) * 1949-06-09 1954-04-13 Donald I Bohn Injection valve and actuating means therefor
DE1052569B (en) * 1954-10-14 1959-03-12 Zahnradfabrik Friedrichshafen Electromagnet
DE1203881B (en) * 1956-05-07 1965-10-28 Detroit Coil Co Electromagnetic actuation device
US3001757A (en) * 1958-04-09 1961-09-26 Chrysler Corp Magnetic fuel injection nozzle
US3534310A (en) * 1966-08-29 1970-10-13 Etablis Public A Caractere Ind Electrical connector for use in conductive media
US3729025A (en) * 1970-08-31 1973-04-24 Bendix Corp Solenoid valve with stroke insensitive port
US3960361A (en) * 1975-03-14 1976-06-01 Bertea Corporation Solenoid valve
US4714234A (en) * 1982-09-07 1987-12-22 Greatbatch Enterprises, Inc. Low power electromagnetic valve
US4656450A (en) * 1986-05-12 1987-04-07 Northern Telecom Limited Transformer and ferrite core structure therefor
US4787418A (en) * 1987-09-15 1988-11-29 Colt Industries Inc. Valve assembly and fuel metering apparatus
US4905962A (en) * 1988-09-15 1990-03-06 Kaiser Aerospace & Electronics Corp. Fast-acting electromagnetic solenoid valve
US6273224B1 (en) * 1997-08-12 2001-08-14 Hr Textron, Inc. Shock absorber mounted electromagnetically operated damper valve
US20030020039A1 (en) * 2001-06-28 2003-01-30 Rainer Haeberer Solenoid valve for controlling an injection valve of an internal combustion engine
US6764061B2 (en) * 2001-06-28 2004-07-20 Robert Bosch Gmbh Solenoid valve for controlling an injection valve of an internal combustion engine
EP1378693A1 (en) * 2002-07-05 2004-01-07 Danfoss A/S Radiator valve
US20190226588A1 (en) * 2014-06-13 2019-07-25 Horiba Stec, Co., Ltd. High conductance valve for fluids and vapors
US10941867B2 (en) * 2014-06-13 2021-03-09 Horiba Stec, Co., Ltd. High conductance valve for fluids and vapors

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